For more information on accessing electronic

This email contains the latest news and developments in neurosurgery and is sent to you from North Bristol NHS Trust

Library & Information Service.

Library & Information Service

Latest News Bulletin

- Neurosurgery -

Contact your local NBT library for:

All enquiries Help with Athens Inter-library loans

Full-text copies of any of the articles below

Literature searches Information skills training

Current awareness bulletins

Your NBT libraries:

Frenchay 0117 340 6570 frenchay.library@nbt.nhs.uk

Southmead 0117 323 5333 southmead.library@nbt.nhs.uk

Primary Care Library (South Plaza) 0117 984 1675 nbn-tr.southplazalibrary@nhs.net

For more information on accessing electronic journals please go to http://library.nhs.uk/booksandjournals/journals/default.aspx

or contact your NBT Library.

1.5T versus 3T MRI for targeting subthalamic nucleus for deep brain stimulation

05 Nov 2013 02:12 pm

British Journal of Neurosurgery, Volume 0, Issue 0, Page 1-4, Early Online.

A new modified speculum guided single nostril technique for endoscopic transnasal transsphenoidal surgery: an analysis of nasal complications

29 Nov 2013 12:21 pm

British Journal of Neurosurgery, Volume 27, Issue 6, Page 742-746, December 2013.

A technique to identify core journals for neurosurgery using citation scatter analysis and the

Bradford distribution across neurosurgery journals

01 Nov 2013 07:31 am

Journal of Neurosurgery, Volume 119, Issue 5, Page 1274-1287, November 2013.

Object The volume of scientific literature doubles approximately every 7 years. The coverage of this literature provided by online compendia is variable and incomplete. It would hence be useful to identify

“core” journals in any field and validate whether the h index and impact factor truly identify the core journals in every subject. The core journals in every medical specialty would be those that provide a current and comprehensive coverage of the science in that specialty. Identifying these journals would make it possible for individual physicians to keep abreast of research and clinical progress. Methods The top 10 neurosurgical journals (on the basis of impact factor and h index) were selected. A database of all articles cited in the reference lists of papers published in issues of these journals published in the first quarter of

2012 was generated. The journals were ranked based on the number of papers cited from each. This

citation rank list was compared with the h index and impact factor rank lists. The rank list was also examined to see if the concept of core journals could be validated for neurosurgical literature using

Bradford's law. Results A total of 22,850 papers spread across 2522 journals were cited in neurosurgical literature over 3 months. Although the top 10 journals were the same, irrespective of ranking criterion (h index, impact factor, citation ranking), the 3 rank lists were not congruent. The top 25% of cited articles obeyed the Bradford distribution; beyond this, there was a zone of increased scatter. Six core journals were identified for neurosurgery. Conclusions The core journals for neurosurgery were identified to be Journal of

Neurosurgery, Neurosurgery, Spine, Acta Neurochirurgica, Stroke, and Journal of Neurotrauma. A list of core journals could similarly be generated for every subject. This would facilitate a focused reading to keep abreast of current knowledge. Collated across specialties, these journals could depict the current status of medical science.

An improved elastase-based method to create a saccular aneurysm rabbit model

29 Nov 2013 12:20 pm


An unusual basal skull injury resulting in CSF leak and a novel method to repair

29 Nov 2013 12:21 pm


Anterior cingulotomy improves malignant mesothelioma pain and dyspnoea

07 Nov 2013 02:06 pm


Anterior sacral meningocele in a patient with currarino syndrome as a cause of ileus

29 Nov 2013 12:20 pm


Cadherin 13 overexpression as an important factor related to the absence of tumor fluorescence in 5-aminolevulinic acid –guided resection of glioma

01 Nov 2013 07:30 am


Object Gliomas contain aggressive malignant cancer, and resection rate remains an important factor in treatment. Currently, fluorescence-guided resection using orally administered 5-aminolevulinic acid (5-ALA) has proved to be beneficial in improving the prognosis of patients with gliomas. 5-ALA is metabolized to protoporphyrin IX (PpIX) that accumulates selectively in the tumor and exhibits strong fluorescence upon excitation, but glioma cells do not always respond to 5-ALA, which can result in incomplete or excessive resection. Several possible mechanisms for this phenomenon have been suggested, but they remain poorly understood. To clarify the probable mechanisms underlying the variable induction of fluorescence and to improve fluorescence-guided surgery, the authors searched for key negative regulators of fluorescent signal induced by 5-ALA. Methods A comprehensive gene expression analysis was performed using microarrays in 11 pairs of tumor specimens, fluorescence-positive and fluorescence-negative tumors, and screened genes overexpressed specifically in fluorescence-negative tumors as the possible candidates for key negative regulators of 5-ALA

–induced fluorescence. The most possible candidate was selected through annotation analysis in combination with a comparison of expression levels, and the relevance of expression of the selected gene to 5-ALA –induced fluorescence in tumor tissues was confirmed in the quantified expression levels. The biological significance of an identified gene in PpIX accumulation and 5-ALA – induced fluorescence was evaluated by in vitro PpIX fluorescence intensity analysis and in vitro PpIX fluorescence molecular imaging in 4 human glioblastoma cell lines (A1207, NMCG1, U251, and U373).

Knockdown analyses using a specific small interfering RNA in U251 cells was also performed to determine the mechanisms of action and genes working as partners in the 5-ALA metabolic pathway. Results The authors chose 251 probes that showed remarkably high expression only in fluorescent-negative tumors

(median intensity of expression signal > 1.0), and eventually the cadherin 13 gene (CDH13) was selected

as the most possible determinant of 5-ALA

–induced fluorescent signal in gliomas. The mean expression level of CDH13 in the fluorescence-negative gliomas was statistically higher than that in positive ones (p =

0.027), and knockdown of CDH13 expression enhanced the fluorescence image and increased the amount of PpIX 13-fold over controls (p < 0.001) in U251 glioma cells treated with 5-ALA. Comprehensive gene expression analysis of the CDH13-knockdown U251 cells demonstrated another two genes possibly involved in the PpIX biosynthesis: ATP-binding cassette transporter (ABCG2) significantly decreased in the

CDH13 knockdown, while oligopeptide transporter 1 (PEPT1) increased. Conclusions The cadherin 13 gene might play a role in the PpIX accumulation pathway and act as a negative regulator of 5-ALA –induced fluorescence in glioma cells. Although further studies to clarify the mechanisms of action in the 5-ALA metabolic pathway would be indispensable, the results of this study might lead to a novel fluorescent marker able to overcome the obstacles of existing fluorescence-guided resection and improve the limited resection rate.

Case report of Os odontoideum causing Ondine's curse

29 Nov 2013 12:21 pm


Cauda equina syndrome: Findings on perineal examination

29 Nov 2013 12:20 pm

British Journal of Neurosurgery, Volume 27, Issue 6, Page 852, December 2013.

Causative role of infection in chronic non-thromboembolic pulmonary hypertension following ventriculo-atrial shunt

01 Nov 2013 09:44 am


Cerebrolysin enhances cognitive recovery of mild traumatic brain injury patients: doubleblind, placebo-controlled, randomized study

29 Nov 2013 12:20 pm


D-dimer plasma level: a reliable marker for venous thromboembolism after elective craniotomy

01 Nov 2013 07:31 am


Object The incidence of deep venous thrombosis (DVT) after craniotomy is reported to be as high as 50%.

In outpatients, D-dimer levels of more than 0.5 mg/L indicate venous thromboembolism (VTE, which subsumes DVT and pulmonary embolism [PE]) with a sensitivity of 99.4% and a specificity of 38.2%.

However, D-dimer levels are believed to be unreliable in postoperative patients. The authors undertook the present study to test the hypothesis that D-dimer levels would be systematically raised in a postoperative population and to define a feasible threshold for identification of VTE. Methods Doppler ultrasonography of the lower extremity was performed pre- and postoperatively to evaluate for DVT in 101 patients who underwent elective craniotomy. D-dimer levels were assessed preoperatively and on the 3rd, 7th, and 10th days after surgery. Statistical analysis was carried out to define a feasible threshold for D-dimer levels.

Results D-dimer plasma levels were found to be systematically raised postoperatively, and they differed between patients with and without VTE in a highly significant way. On the 3rd day after surgery, D-dimer levels of more than 2 mg/L indicated VTE with a sensitivity of 95.3% and a specificity of 74.1%, allowing for the definition of a feasible threshold. D-dimer levels of more than 4 mg/L were observed in all patients who had PE during the postoperative period (n = 9). Ventilation time and duration of surgery were identified as highly significant risk factors for the development of VTE. Conclusions Using a threshold of 2 mg/L, D-dimer levels will indicate VTE with a high degree of sensitivity and specificity in patients who have undergone craniotomy. Pulmonary embolism seems to be indicated by even higher D-dimer levels. Given that the development of D-dimer plasma levels in the postoperative period follows a principle that can be predicted

and that deviations from it indicate VTE, this principle might be applicable to other types of surgery.

Decreased risk of acute kidney injury with intracranial pressure monitoring in patients with moderate or severe brain injury

01 Nov 2013 07:31 am


Object The authors undertook this study to evaluate the effects of continuous intracranial pressure (ICP) monitoring –directed mannitol treatment on kidney function in patients with moderate or severe traumatic brain injury (TBI). Methods One hundred sixty-eight patients with TBI were prospectively assigned to an ICP monitoring group or a conventional treatment control group based on the Brain Trauma Foundation guidelines. Clinical data included the dynamic changes of patients' blood concentrations of cystatin C, creatinine (Cr), and blood urea nitrogen (BUN); mannitol use; and 6-month Glasgow Outcome Scale (GOS) scores. Results There were no statistically significant differences with respect to hospitalized injury, age, or sex distribution between the 2 groups. The incidence of acute kidney injury (AKI) was higher in the control group than in the ICP monitoring group (p < 0.05). The mean mannitol dosage in the ICP monitoring group

(443 ± 133 g) was significantly lower than in the control group (820 ± 412 g) (p < 0.01), and the period of mannitol use in the ICP monitoring grou p (3 ± 3.8 days) was significantly shorter than in the control group (7

± 2.3 days) (p < 0.01). The 6-month GOS scores in the ICP monitoring group were significantly better than in the control group (p < 0.05). On the 7th, 14th, and 21st days after injury, the plasma cystatin C and Cr concentrations in the ICP-monitoring group were significantly higher than the control group (p < 0.05).

Conclusions In patients with moderate and severe TBI, ICP-directed mannitol treatment demonstrated a beneficial effect on reducing the incidence of AKI compared with treatment directed by neurological signs and physiological indicators.

Delayed haemorrhage in the splenium of the corpus callosum after aneurysm rupture

29 Nov 2013 12:20 pm


Dermoid cysts of the posterior fossa – morbid associations of a benign lesion

29 Nov 2013 12:20 pm


Diagnostic work up for language testing in patients undergoing awake craniotomy for brain lesions in language areas

06 Nov 2013 10:49 pm


Dissecting aneurysm at the A1 segment of the anterior cerebral artery presenting as visual loss and visual field defect

29 Nov 2013 12:19 pm


Editorial

29 Nov 2013 12:21 pm


Editorial: Core journals

01 Nov 2013 07:31 am


Editorial: Functional mapping

01 Nov 2013 07:30 am


Editorial: Intracranial pressure monitoring for brain injury

01 Nov 2013 07:31 am


Editorial: Medial temporal epilepsy

01 Nov 2013 07:31 am


Editorial: Subconcussion in traumatic brain injury

01 Nov 2013 07:30 am


Editorial: The biological advantage of single-session radiosurgery

01 Nov 2013 07:30 am


Editorial: Treatment guidelines from the Brain Trauma Foundation

01 Nov 2013 07:31 am


Effect of symptomatic pseudomeningocele on improvement in pain, disability, and quality of life following suboccipital decompression for adult Chiari malformation Type I

01 Nov 2013 07:30 am


Object Suboccipital decompression is a common procedure for patients with Chiari malformation Type I

(CMI). Published studies have reported complication rates ranging from 3% to 40%, with pseudomeningocele being one of the most common complications. To date, there are no studies assessing the effect of this complication on long-term outcome. Therefore, the authors set out to assess the effect of symptomatic pseudomeningocele on patient outcomes following suboccipital decompression for CM-I.

Methods The study comprised 50 adult patients with CM-I who underwent suboccipital craniectomy and C-1 laminectomy with or without duraplasty. Clinical presentation, radiological studies, operative variables, and complications were assessed for each case. Baseline and 1-year postoperative patient-reported outcomes were assessed to determine improvement in pain, disability, and quality of life. The extent of improvement was compared for patients with and without development of a postoperative symptomatic pseudomeningocele. Results A symptomatic pseudomeningocele developed postoperatively in 9 patients

(18%). There was no difference with regard to clinical, radiological, or operative variables for patients with or without a postoperative pseudomeningocele. Patients without a pseudomeningocele had significant improvement in all 9 patient-reported outcome measures assessed. On the other hand, patients with pseudomeningocele only had significant improvement in headache (as measured on the Numeric Rating

Scale) and headache-related disability (as measured on the Headache Disability Index) but no improvement in quality of life. Twenty-nine (71%) of 41 patients without a pseudomeningocele reported improvement in health status postoperatively compared with only 3 (33%) of 9 patients with a postoperative pseudomeningocele (p = 0.05). Conclusions Surgical management of CM-I in adults provides significant and sustained improvement in pain, disability, general health, and quality of life. Development of a postoperative symptomatic pseudomeningocele has lingering effects at 1 year, and it significantly diminishes the overall benefit of suboccipital decompression for CM-related symptoms. Further research is needed to accurately predict which patients may benefit from decompression alone without duraplasty.

Electrostatic discharges and their effect on the validity of registered values in intracranial pressure monitors

01 Nov 2013 07:31 am


Object Intracranial pressure (ICP) monitoring is used extensively in clinical practice, and as such, the accuracy of registered ICP values is paramount. Clinical observations of nonphysiological changes in ICP have called into question the accuracy of registered ICP values. Subsequently, the authors have tried to determine if the ICP monitors from major manufacturers were affected by electrostatic discharges (ESDs), if the changes were permanent or transient in nature, and if the changes were modified by the addition of different electrical appliances normally used in the neurointensive care unit environment. Methods The authors established a test setup in the neurointensive care unit using a large container filled with isotonic saline, creating a phantom patient. Intracranial pressure monitors were sequentially lowered into the container and subjected to a predefined test battery of ESDs. Results Five pressure monitors from 4 manufacturers were evaluated. Three monitors containing electrical circuitry at the tip of the transducer were all affected by ESDs. Clinically significant permanent changes in the reported ICP values for 1 pressure monitor were observed, as well as temporary deflections for 2 other monitors. The monitors had different levels of sensitivity to discharges at low voltages. Conclusions These results explain some of the sudden shifts in ICP noted in the clinical setting. However, a clear deflection pattern related to the addition of electrical appliances was not found. The authors recommend instituting policies for reducing the risk of subjecting patients to ESDs in the neurointensive care unit setting.

Endometriosis of conus medullaris: a case report

29 Nov 2013 12:20 pm


Endoscopic endonasal surgery for craniopharyngiomas: surgical outcome in 64 patients

01 Nov 2013 07:31 am


Object The proximity of craniopharyngiomas to vital neurovascular structures and their high recurrence rates make them one of the most challenging and controversial management dilemmas in neurosurgery.

Endoscopic endonasal surgery (EES) has recently been introduced as a treatment option for both pediatric and adult craniopharyngiomas. The object of the present study was to present the results of EES and analyze outcome in both the pediatric and the adult age groups. Methods The authors retrospectively reviewed the records of patients with craniopharyngioma who had undergone EES in the period from June

1999 to April 2011. Results Sixty-four patients, 47 adults and 17 children, were eligible for this study. Fortyseven patients had presented with primary craniopharyngiomas and 17 with recurrent tumors. The mean age in the adult group was 51 years (range 28 –82 years); in the pediatric group, 9 years (range 4–18 years). Overall, the gross-total resection rate was 37.5% (24 patients); near-total resection (> 95% of tumor removed) was 34.4% (22 patients); subtotal resection (≥ 80% of tumor removed) 21.9% (14 patients); and partial resection (< 80% of tumor removed) 6.2% (4 patients). In 9 patients, EES had been combined with radiation therapy (with radiosurgery in 6 cases) as the initial treatment. Among the 40 patients (62.5%) who had presented with pituitary insufficiency, pituitary function remained unchanged in 19 (47.5%), improved or normalized in 8 (20%), and worsened in 13 (32.5%). In the 24 patients who had presented with normal pituitary function, new pituitary deficit occurred in 14 (58.3%). Nineteen patients (29.7%) suffered from diabetes insipidus at presentation, and the condition developed in 21 patients (46.7%) after treatment.

Forty-four patients (68.8%) had presented with impaired vision. In 38 (86.4%) of them, vision improved or even normalized after surgery; in 5, it remained unchanged; and in 1, it temporarily worsened. One patient without preoperative visual problems showed temporary visual deterioration after treatment. Permanent visual deterioration occurred in no one after surgery. The mean follow-up was 38 months (range 1 –135 months). Tumor recurrence after EES was discovered in 22 patients (34.4%) and was treated with repeat surgery (6 patients), radiosurgery (1 patient), combined repeat surgery and radiation therapy (8 patients), interferon (1 patient), or observation (6 patients). Surgical complications included 15 cases (23.4%) with

CSF leakage that was treated with surgical reexploration (13 patients) and/or lumbar drain placement (9 patients). This leak rate was decreased to 10.6% in recent years after the introduction of the vascularized nasoseptal flap. Five cases (7.8%) of meningitis were found and treated with antibiotics without further complications. Postoperative hydrocephalus occurred in 7 patients (12.7%) and was treated with

ventriculoperitoneal shunt placement. Five patients experienced transient cranial nerve palsies. There was no operative mortality. Conclusions With the goal of gross-total or maximum possible safe resection, EES can be used for the treatment of every craniopharyngioma, regardless of its location, size, and extension

(excluding purely intraventricular tumors), and can provide acceptable results comparable to those for traditional craniotomies. Endoscopic endonasal surgery is not limited to adults and actually shows higher resection rates in the pediatric population.

Endoscopic transnasal approach to the pituitary – Operative technique and nuances

29 Nov 2013 12:20 pm


Epidural spinal cord compression in Langerhans cell histiocytosis: A case report

29 Nov 2013 12:20 pm


Erratum: Correction to: Swelling and enhancement of the cervical spinal cord: when is a tumour not a tumour?

29 Nov 2013 12:20 pm


Evaluation of the clinical efficacy of multiple lower-extremity nerve decompression in diabetic peripheral neuropathy

29 Nov 2013 12:21 pm


Expansion of CD133-positive glioma cells in recurrent de novo glioblastomas after radiotherapy and chemotherapy

01 Nov 2013 07:30 am


Object Recent evidence suggests that a glioma stem cell subpopulation may determine the biological behavior of tumors, including resistance to therapy. To investigate this hypothesis, the authors examined varying grades of gliomas for stem cell marker expressions and histopathological changes between primary and recurrent tumors. Methods Tumor samples were collected during surgery from 70 patients with varying grades of gliomas (Grade II in 12 patients, Grade III in 16, and Grade IV in 42) prior to any adjuvant treatment. The samples were subjected to immunohistochemistry for MIB-1, factor VIII, GFAP, and stem cell markers (CD133 and nestin). Histopathological changes were compared between primary and recurrent tumors in 31 patients after radiation treatment and chemotherapy, including high-dose irradiation with additional stereotactic radiosurgery. Results CD133 expression on glioma cells was confined to de novo glioblastomas but was not observed in lower-grade gliomas. In de novo glioblastomas, the mean percentage of CD133positive glioma cells in sections obtained at recurrence was 12.2% ± 10.3%, which was significantly higher than that obtained at the primary surgery (1.08% ± 1.78%). CD133 and Ki 67 dualpositive glioma cells were significantly increased in recurrent de novo glioblastomas as compared with those in primary tumors (14.5% ± 6.67% vs 2.16% ± 2.60%, respectively). In contrast, secondary glioblastomas rarely expressed CD133 antigen even after malignant progression following radiotherapy and chemotherapy. Conclusions The authors' results indicate that CD133-positive glioma stem cells could survive, change to a proliferative cancer stem cell phenotype, and cause recurrence in cases with de novo glioblastomas after radiotherapy and chemotherapy.

Foramen ovale puncture, lesioning accuracy, and avoiding complications: microsurgical anatomy study with clinical implications

01 Nov 2013 07:30 am


Object Foramen ovale (FO) puncture allows for trigeminal neuralgia treatment, FO electrode placement,

and selected biopsy studies. The goals of this study were to demonstrate the anatomical basis of complications related to FO puncture, and provide anatomical landmarks for improvement of safety, selective lesioning of the trigeminal nerve (TN), and optimal placement of electrodes. Methods Both sides of

50 dry skulls were studied to obtain the distances from the FO to relevant cranial base references. A total of

36 sides from 18 formalin-fixed specimens were dissected for Meckel cave and TN measurements. The best radiographic projection for FO visualization was assessed in 40 skulls, and the optimal trajectory angles, insertion depths, and topographies of the lesions were evaluated in 17 specimens. In addition, the differences in postoperative pain relief after the radiofrequency procedure among different branches of the

TN were statistically assessed in 49 patients to determine if there was any TN branch less efficiently targeted. Results Most severe complications during FO puncture are related to incorrect needle placement intracranially or extracranially. The needle should be inserted 25 mm lateral to the oral commissure, forming an approximately 45° angle with the hard palate in the lateral radiographic view, directed 20° medially in the anteroposterior view. Once the needle reaches the FO, it can be advanced by 20 mm, on average, up to the petrous ridge. If the needle/radiofrequency electrode tip remains more than 18 mm away from the midline, injury to the cavernous carotid artery is minimized. Anatomically there is less potential for complications when the needle/radiofrequency electrode is advanced no more than 2 mm away from the clival line in the lateral view, when the needle pierces the medial part of the FO toward the medial part of the trigeminal impression in the petrous ridge, and no more than 4 mm in the lateral part. The 40°/45° inferior transfacial–

20° oblique radiographic projection visualized 96.2% of the FOs in dry skulls, and the remainder were not visualized in any other projection of the radiograph. Patients with V1 involvement experienced postoperative pain more frequently than did patients with V2 or V3 involvement. Anatomical targeting of V1 in specimens was more efficiently achieved by inserting the needle in the medial third of the FO; for V2 targeting, in the middle of the FO; and for V3 targeting, in the lateral third of the FO. Conclusions Knowledge of the extracranial and intracranial anatomical relationships of the FO is essential to understanding and avoiding complications during FO puncture. These data suggest that better radiographic visualization of the FO can improve lesioning accuracy depending on the part of the FO to be punctured. The angles and safety distances obtained may help the neurosurgeon minimize complications during FO puncture and TN lesioning.

Gamma Knife surgery anterior capsulotomy for severe and refractory obsessive-compulsive disorder

01 Nov 2013 07:30 am


Object Obsessive-compulsive disorder (OCD) is a challenging psychiatric condition associated with anxiety and ritualistic behaviors. Although medical management and psychiatric therapy are effective for many patients, severe and extreme cases may prove refractory to these approaches. The authors evaluated their experience with Gamma Knife (GK) capsulotomy in treating patients with severe OCD. Methods A retrospective review of an institutional review board –approved prospective clinical GK database was conducted for patients treated for severe OCD. All patients were evaluated preoperatively by at least one psychiatrist, and their condition was deemed refractory to pharmacological and psychiatric therapy. Results

Five patients were identified. Gamma Knife surgery with the GK Perfexion unit was used to target the anterior limb of the internal capsule bilaterally. A single 4-mm isocenter was used; maximum radiation doses of 140

–160 Gy were delivered. All 5 patients were preoperatively and postoperatively assessed for clinical response by using both subjective and objective metrics, including the Yale-Brown Obsessive

Compulsive Scale (YBOCS); 4 of the 5 patients had postoperative radiological follow-up. The median clinical follow-up was 24 months (range 6 –33 months). At the time of radiosurgery, all patients had YBOCS scores in the severe or extreme range (median 32, range 31 –34). At the last follow-up, 4 (80%) of the 5 patients showed marked clinical improvement; in the remaining patient (20%), mild improvement was seen.

The median YBOCS score was 13 (range 12

–31) at the last follow-up. Neuroimaging studies at 6 months after GK treatment demonstrated a small area of enhancement corresponding to the site of the isocenter and some mild T2 signal changes in the internal capsule. No adverse clinical effects were noted from the radiosurgery. Conclusions For patients with severe OCD refractory to medications and psychiatric therapy,

GK capsulotomy afforded clinical improvement. Further study of this approach seems warranted.

Hypertension in patients with cranial nerve vascular compression syndromes and comparison with a population-based cohort

01 Nov 2013 07:31 am


Object Although essential arterial hypertension (AH) represents a major health issue, its underlying causes remain unknown. An intriguing hypothesis is that AH in some cases may be caused by vascular compression of the rostral ventrolateral medulla (RVLM). Because hemifacial spasms (HFSs) are caused by vascular compression of the seventh cranial nerve in close proximity to the RVLM, one would, if this hypothesis is correct, expect to find a positive association between the occurrence of AH and chronic HFSs.

Such a positive association would not be expected in patients with trigeminal neuralgia (TN), since TN is caused by vascular compression of the fifth cranial nerve, which is not close to the RVLM. Methods In view of this background, the authors conducted a retrospective population-based study to investigate how the occurrence of AH in patients with either HFSs or TN compares with the prevalence of AH in the general population, when adjusted for sex and age. The general population was represented by participants of the

NordTrøndelag Health Study 3 (HUNT3). Results The prevalence of AH in the authors' patients with HFSs was significantly higher than in a sex- and age-adjusted sample from the general population; this was not true for the patients with TN. Conclusions The authors suggest that the data provide supporting evidence to the theory that compression of the RVLM may be one cause of AH.

Indications for intracranial reservoirs: A six-year study

07 Nov 2013 02:06 pm


Intracranial biomechanics following cortical contusion in live rats

01 Nov 2013 07:31 am


Object The goal of this study was to examine the mechanical properties of living rat intracranial contents and corresponding brain structural alterations following parietal cerebral cortex contusion. Methods After being anesthetized, young adult rats were subjected to parietal craniotomy followed by cortical contusion using a calibrated weight-drop method. Magnetic resonance imaging was used to visualize the contusion.

At the site of contusion, instrumented force-controlled indentation was performed 2 hours to 21 days later on the intact dural surface. The force-deformation (stress-strain) relationship was used to calculate elastic

(indentation modulus) and strain changes over time, and constant hold or cyclic stress was used to evaluate viscoelastic deformation. These measurements were followed by histological studies. Results At contusion sites, the indentation modulus was significantly decreased at 1 –3 days and tended to be above control values at 21 days. Multicycle indentation showed that the brain tended to accumulate more strain (an indicator of viscosity) by 1 day after the contusion. Imaging and histological studies showed local edema and hemorrhage at 6 hours to 3 days and accumulation of reactive astrocytes, which began at 3 days and was pronounced by 21 days. Conclusions The viscoelastic properties of living rat brain change following contusion. Initially, edema and tissue necrosis occur, and the brain becomes less elastic and less viscous.

Later, along with undergoing reactive astroglial changes, the brain tends to become stiffer than normal.

These quantitative data, which are related to the physical changes in the brain following trauma and which reflect subjective impressions upon palpation, will be useful for understanding emerging diagnostic tools such as magnetic resonance elastography.

Intracranial pressure monitoring in severe head injury: compliance with Brain Trauma

Foundation guidelines and effect on outcomes: a prospective study

01 Nov 2013 07:31 am


Object The Brain Trauma Foundation (BTF) has established guidelines for intracranial pressure (ICP) monitoring in severe traumatic brain injury (TBI). This study assessed compliance with these guidelines and the effect on outcomes. Methods This is a prospective, observational study including patients with severe blunt TBI (Glasgow Coma Scale score ≤ 8, head Abbreviated Injury Scale score ≥ 3) between January 2010 and December 2011. Demographics, clinical characteristics, laboratory profile, head CT scans, injury severity indices, and interventions were collected. The study population was stratified into 2 study groups:

ICP monitoring and no ICP monitoring. Primary outcomes included compliance with BTF guidelines, overall in-hospital mortality, and mortality due to brain herniation. Secondary outcomes were ICU and hospital lengths of stay. Multiple regression analyses were deployed to determine the effect of ICP monitoring on outcomes. Results A total of 216 patients met the BTF guideline criteria for ICP monitoring. Compliance with BTF guidelines was 46.8% (101 patients). Patients with subarachnoid hemorrhage and those who underwent craniectomy/craniotomy were significantly more likely to undergo ICP monitoring. Hypotension,

coagulopathy, and increasing age were negatively associated with the placement of ICP monitoring devices. The overall in-hospital mortality was significantly higher in patients who did not undergo ICP monitoring (53.9% vs 32.7%, adjusted p = 0.019). Similarly, mortality due to brain herniation was significantly higher for the group not undergoing ICP monitoring (21.7% vs 12.9%, adjusted p = 0.046). The

ICU and hospital lengths of stay were significantly longer in patients subjected to ICP monitoring.

Conclusions Compliance with BTF ICP monitoring guidelines in our study sample was 46.8%. Patients managed according to the BTF ICP guidelines experienced significantly improved survival.

Intractable headache after excision of an acoustic neuroma treated by stent revascularisation of the sigmoid sinus

29 Nov 2013 12:19 pm


Laboratory training in the retrosigmoid approach using cadaveric silicone injected cow brain

29 Nov 2013 12:21 pm


Letter to the Editor: Angiogenesis

01 Nov 2013 07:31 am


Letter to the Editor: Beta-amyloid oligomer

01 Nov 2013 07:30 am

Journal of Neurosurgery, Volume 119, Issue 5, Page 1352, November 2013.

Letter to the Editor: Closed head injury

01 Nov 2013 07:31 am


Letter to the Editor: Cognitive assessment in glioma patients

01 Nov 2013 07:30 am


Letter to the Editor: Diffuse low-grade gliomas

01 Nov 2013 07:31 am


Letter to the Editor: Indocyanine green videography and meningioma

01 Nov 2013 07:31 am


Letter to the Editor: Microelectrode recording and deep brain stimulation

01 Nov 2013 07:30 am


Letter to the Editor: Occipital lobe

01 Nov 2013 07:31 am


Letter to the Editor: Outcome prediction in traumatic brain injury

01 Nov 2013 07:31 am


Letter to the Editor: Shaving

01 Nov 2013 07:30 am


Long-term outcome of high-dose Gamma Knife surgery in treatment of trigeminal neuralgia

01 Nov 2013 07:31 am


Object Despite the widespread use of Gamma Knife surgery (GKS) for trigeminal neuralgia (TN), controversy remains regarding the optimal treatment dose and target site. Among the published studies, only a few have focused on long-term outcomes (beyond 2 years) using 90 Gy, which is in the higher range of treatment doses used (70 –90 Gy). Methods The authors followed up on 315 consecutive patients treated with the Leksell Gamma Knife unit using a 4-mm isocenter without blocks. The isocenter was placed on the trigeminal nerve with the 20% isodose line tangential to the pontine surface (18 Gy). At follow-up, 33 patients were deceased; 282 were mailed an extensive questionnaire regarding their outcomes, but 32 could not be reached. The authors report their analysis of the remaining 250 cases. The patients' mean age at the time of survey response and the mean duration of followup were 70.8 ± 13.1 years and 68.9 ± 41.8 months, respectively. Results One hundred eighty-five patients (85.6%) had decreased pain intensity after

GKS. Modified Marseille Scale (MMS) pain classifications after GKS at follow-up were: Class I (pain free without medication[s]) in 104 (43.7%), Class II (pain free with medication[s]) in 66 (27.7%), Class III (> 90% decrease in pain intensity) in 23 (9.7%), Class IV (50% –90% decrease in pain intensity) in 20 (8.4%), Class

V (< 50% decrease in pain intensity) in 11 (4.6%), and Class VI (pain becoming worse) in 14 (5.9%).

Therefore, 170 patients (71.4%) were pain free (Classes I and II) and 213 (89.5%) had at least 50% pain relief. All patients had pain that was refractory to medical management prior to GKS, but only 111 (44.4%) were being treated with medication at follow-up (p < 0.0001). Eighty patients (32.9%) developed numbness after GKS, and 74.5% of patients with numbness had complete pain relief. Quality of life and patient satisfaction on a 10point scale were reported at mean values (± SD) of 7.8 ± 3.1 and 7.7 ± 3.4, respectively. Most of the patients (87.7%) would recommend GKS to another patient. Patients with prior surgical treatments had increased latency to pain relief and were more likely to continue medicines (p <

0.05). Moreover, presence of altered facial sensations prior to radiosurgery was associated with higher pain intensity, longer pain episodes, more frequent pain attacks, worse MMS pain classification, and more medication use after GKS (p < 0.05). Conversely, increase in numbness intensity after GKS was associated with a decrease in pain intensity and pain length (p < 0.05). Conclusions Gamma Knife surgery using a maximum dose of 90 Gy to the trigeminal nerve provides satisfactory long-term pain control, reduces the use of medication, and improves quality of life. Physicians must be aware that higher doses may be associated with an increase in bothersome sensory complications. The benefits and risks of higher dose selection must be carefully discussed with patients, since facial numbness, even if bothersome, may be an acceptable trade-off for patients with severe pain.

MGMT promoter methylation status and prognosis of patients with primary or recurrent glioblastoma treated with carmustine wafers

29 Nov 2013 12:19 pm


Markers of cell division cycle in glioblastoma: significance in prediction of treatment response and patient prognosis

29 Nov 2013 12:21 pm


Massive cerebral involvement in fat embolism syndrome and intracranial pressure management

01 Nov 2013 07:31 am


Fat embolism syndrome (FES) is a common clinical entity that can occasionally have significant neurological sequelae. The authors report a case of cerebral fat embolism and FES that required surgical management of intracranial pressure (ICP). They also discuss the literature as well as the potential need for neurosurgical management of this disease entity in select patients. A 58-year-old woman presented with a seizure episode and altered mental status after suffering a right femur fracture. Head CT studies demonstrated hypointense areas consistent with fat globules at the gray-white matter junction predominantly in the right hemisphere. This CT finding is unique in the literature, as other reports have not included imaging performed early enough to capture this finding. Brain MR images obtained 3 days later

revealed T2-hyperintense areas with restricted diffusion within the same hemisphere, along with midline shift and subfalcine herniation. These findings steered the patient to the operating room for decompressive hemicraniectomy. A review of the literature from 1980 to 2012 disclosed 54 cases in 38 reports concerning cerebral fat embolism and FES. Analysis of all the cases revealed that 98% of the patients presented with mental status changes, whereas only 22% had focal signs and/or seizures. A good outcome was seen in

57.6% of patients with coma and/or abnormal posturing on presentation and in 90.5% of patients presenting with mild mental status changes, focal deficits, or seizure. In the majority of cases ICP was managed conservatively with no surgical intervention. One case featured the use of an ICP monitor, while none featured the use of hemicraniectomy.

Muscle and nerve biopsy for the neurosurgical trainee

29 Nov 2013 12:20 pm


Nonthermal ablation with microbubble-enhanced focused ultrasound close to the optic tract without affecting nerve function

01 Nov 2013 07:30 am


Object Tumors at the skull base are challenging for both resection and radiosurgery given the presence of critical adjacent structures, such as cranial nerves, blood vessels, and brainstem. Magnetic resonance imaging

–guided thermal ablation via laser or other methods has been evaluated as a minimally invasive alternative to these techniques in the brain. Focused ultrasound (FUS) offers a noninvasive method of thermal ablation; however, skull heating limits currently available technology to ablation at regions distant from the skull bone. Here, the authors evaluated a method that circumvents this problem by combining the

FUS exposures with injected microbubble-based ultrasound contrast agent. These microbubbles concentrate the ultrasound-induced effects on the vasculature, enabling an ablation method that does not cause significant heating of the brain or skull. Methods In 29 rats, a 525-kHz FUS transducer was used to ablate tissue structures at the skull base that were centered on or adjacent to the optic tract or chiasm. Lowintensity, low-duty-cycle ultrasound exposures (sonications) were applied for 5 minutes after intravenous injection of an ultrasound contrast agent (Definity, Lantheus Medical Imaging Inc.). Using histological analysis and visual evoked potential (VEP) measurements, the authors determined whether structural or functional damage was induced in the optic tract or chiasm. Results Overall, while the sonications produced a well-defined lesion in the gray matter targets, the adjacent tract and chiasm had comparatively little or no damage. No significant changes (p > 0.05) were found in the magnitude or latency of the VEP recordings, either immediately after sonication or at later times up to 4 weeks after sonication, and no delayed effects were evident in the histological features of the optic nerve and retina. Conclusions This technique, which selectively targets the intravascular microbubbles, appears to be a promising method of noninvasively producing sharply demarcated lesions in deep brain structures while preserving function in adjacent nerves.

Because of low vascularity —and thus a low microbubble concentration—some large white matter tracts appear to have some natural resistance to this type of ablation compared with gray matter. While future work is needed to develop methods of monitoring the procedure and establishing its safety at deep brain targets, the technique does appear to be a potential solution that allows FUS ablation of deep brain targets while sparing adjacent nerve structures.

Oxford Case Histories in Neurosurgery (first edition). Eds. Harutomo Hasegawa, Matthew

Crocker, Pawan Singh Minhas

29 Nov 2013 12:21 pm


Partly reversible central auditory dysfunction induced by cerebral vasospasm after subarachnoid hemorrhage

01 Nov 2013 07:31 am


The authors describe a rare case of central auditory dysfunction induced by cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH). A 55-year-old woman who was admitted after aneurysmal

SAH developed cerebral vasospasm on Day 3 affecting mainly the right middle cerebral artery (MCA) and partly the left MCA. The vasospasm became refractory to conventional therapy and was ultimately improved

by intraarterial infusion of nimodipine in the right MCA and angioplasty. Severe auditory dysfunction was apparent from Day 10 as the patient was not reactive to speech or environmental sounds. Brain MRI on

Day 17 demonstrated infarcted areas mainly in the right hippocampus, medial occipital lobe, and thalamus.

The patient underwent further examination using audiometry, speech testing, auditory evoked potentials, functional MRI, and cerebral PET. The initial diagnosis was extended nonverbal agnosia and total pure word deafness. The central auditory dysfunction improved over 6 months, with persisting hyperacusis, tinnitus, and amusia. Central auditory dysfunction is a rare complication after SAH. While cortical deafness may be associated with bilateral lesions of the temporal cortex, partly reversible central auditory dysfunction was observed in this patient after prominently unilateral right temporal lesions. The role of the interthalamic connections can be discussed, as well as the possibility that a less severe vasospasm on the left MCA could have transiently impaired the left thalamocortical auditory pathways.

Pilot study of perioperative accidental durotomy: does the period of postoperative bed rest reduce the incidence of complication?

29 Nov 2013 12:21 pm


Pleomorphic xanthoastrocytoma: Long-term results of surgical treatment and analysis of prognostic factors

29 Nov 2013 12:20 pm


Predictors of mortality in nontraumatic subdural hematoma

01 Nov 2013 07:31 am


Object Subdural hematoma (SDH) is a common diagnosis in neurosurgical and neurocritical practice.

Comprehensive outcome data are lacking for nontraumatic SDH. The authors determined which factors are associated with in-hospital mortality in a large sample of patients with nontraumatic SDH. Methods Using the Nationwide Inpatient Sample, the authors selected adults who had been hospitalized in the US between

2007 and 2009 and in whom a primary diagnosis of nontraumatic SDH (ICD-9-CM code 432.1) had been made. Demographics, comorbidities, surgical treatment, and discharge outcomes were identified. Univariate and multivariate analyses were performed to identify predictors of in-hospital mortality. Results Among

14,093 patients with acute nontraumatic SDH, the mean age was 71.4 ± 14.8 (mean ± standard deviation).

In addition, 22.2% of the patients were admitted during the weekend. Surgical evacuation was performed in

51.4% of the patients, and 11.8% of all patients died during hospitalization. In multivariate analyses, patient age (adjusted OR 1.02, 95% CI 1.012

–1.022), congestive heart failure (adjusted OR 1.42, 95% CI 1.19–

1.71), warfarin use (adjusted OR 1.41, 95% CI 1.17

–1.70), coagulopathy (adjusted OR 2.14, 95% CI 1.75–

2.61), mechanical ventilation (adjusted OR 16.85, 95% CI 14.29

–19.86), and weekend admission (adjusted

OR 1.19, 95% CI 1.02

–1.38) were independent predictors of in-hospital mortality. Race (Hispanic: adjusted

OR 0.65, 95% CI 0.51

–0.83; black: adjusted OR 0.78, 95% CI 0.63–0.96), urban hospital location (adjusted

OR 0.69, 95% CI 0.54

–0.89), and surgical SDH evacuation (adjusted OR 0.52, 95% CI 0.45–0.60) were strong independent predictors for decreased mortality. Conclusions One in 9 patients with nontraumatic

SDH dies during hospitalization. Among the several predictors of in-hospital mortality, the weekend effect and treatment with surgical evacuation are potentially modifiable factors. Further investigation may lead to improvements in management and outcomes.

Primary central nervous system malignant lymphoma in a patient with rheumatoid arthritis receiving low-dose methotrexate treatment

29 Nov 2013 12:21 pm


Primary cerebral myxopapillary ependymoma presenting with intratumoral hemorrhage

14 Nov 2013 03:08 pm


Primary intradural extraosseous Ewing's sarcoma of the lumbar spine presenting with acute bleeding

29 Nov 2013 12:21 pm


Proposal for establishment of the UK Cranial Reconstruction Registry (UKCRR)

18 Nov 2013 01:06 pm


REVIEWERS

29 Nov 2013 12:20 pm


Recovery of oculomotor nerve palsy secondary to posterior communicating artery aneurysms*

11 Nov 2013 12:00 pm


Remote site intracranial haemorrhage: a clinical series of five patients with review of literature

29 Nov 2013 12:21 pm


Retroclival subdural haematoma secondary to pituitary apoplexy

29 Nov 2013 12:21 pm


Right parietal cortex and calculation processing: intraoperative functional mapping of multiplication and addition in patients affected by a brain tumor

01 Nov 2013 07:30 am


Object The role of parietal areas in number processing is well known. The significance of intraoperative functional mapping of these areas has been only partially explored, however, and only a few discordant data are available in the surgical literature with regard to the right parietal lobe. The purpose of this study was to evaluate the clinical impact of simple calculation in cortical electrostimulation of right-handed patients affected by a right parietal brain tumor. Methods Calculation mapping in awake surgery was performed in 3 right-handed patients affected by high-grade gliomas located in the right parietal lobe.

Preoperatively, none of the patients presented with calculation deficits. In all 3 cases, after sensorimotor and language mapping, cortical and intraparietal sulcus areas involved in single-digit multiplication and addition calculations were mapped using bipolar electrostimulation. Results In all patients, different sites of the right parietal cortex, mainly in the inferior lobule, were detected as being specifically related to calculation (multiplication or addition). In 2 patients the intraparietal sulcus was functionally specific for multiplication. No functional sites for language were detected. All sites functional for calculation were spared during tumor resection, which was complete in all cases without postoperative neurological deficits.

Conclusions These findings provide intraoperative data in support of an anatomofunctional organization for multiplication and addition within the right parietal area. Furthermore, the study shows the potential clinical relevance of intraoperative mapping of calculation in patients undergoing surgery in the right parietal area.

Further and larger studies are needed to confirm these data and assess whether mapped areas are effectively essential for function.

Risks for hemorrhagic complications after placement of external ventricular drains with early chemical prophylaxis against venous thromboembolisms

01 Nov 2013 07:31 am


Object Patients undergoing placement of an external ventricular drain (EVD) are at increased risk for development of venous thromboembolisms (VTEs). Early chemical prophylaxis has been shown to decrease rates of embolism formation, but the risks for bleeding and the optimal time to initiate prophylaxis have not been clearly defined for this patient population. The authors evaluated the safety and risks for

bleeding when chemical prophylaxis for VTEs was started within 24 hours of EVD placement. Methods To compare rates of hemorrhage among patients who received prophylaxis within 24 hours and those who received it later than 24 hours after admission, the authors conducted an institutional review board – approved retrospective review. Patients were those who had had an EVD placed and postprocedural imaging conducted at Bellevue Hospital, New York, from January 2009 through April 2012. Data collected included demographics, diagnosis, coagulation panel results, time to VTE prophylaxis and imaging, and occurrence of VTEs. The EVD-associated hemorrhages were classified as Grade 0, no hemorrhage; Grade

1, petechial hyperdensity near the drain; Grade 2, hematoma of 1 –15 ml; Grade 3, epidural or subdural hematoma greater than 15 ml; or Grade 4, intraventricular hemorrhage or hematoma requiring surgical intervention. Results Among 99 patients, 111 EVDs had been placed. Low-dose unfractionated heparin had been given within 24 hours of admission (early prophylaxis) to 56 patients and later than 24 hours after admission (delayed prophylaxis) to 55 patients. There were no statistical differences across all grades (0 –4) among those who received early prophylaxis (n = 45, 5, 5, 1, and 0, respectively) and those who received delayed prophylaxis (n = 46, 4, 1, 1, and 3, respectively) (p = 0.731). In the early prophylaxis group, 3 VTEs were discovered among 32 of 56 patients screened for clinically suspected VTEs. In the delayed prophylaxis group, 5 VTEs were discovered among 33 of 55 patients screened for clinically suspected VTEs

(p = 0.71). Conclusions Hemorrhagic complications did not increase when chemical prophylaxis was started within 24 hours of admission. Also, the incidence of VTEs did not differ between patients in the early and delayed prophylaxis groups. Larger randomized controlled trials are probably needed to assess decreases in VTEs with earlier prophylaxis.

Role of subconcussion in repetitive mild traumatic brain injury

01 Nov 2013 07:30 am


Research now suggests that head impacts commonly occur during contact sports in which visible signs or symptoms of neurological dysfunction may not develop despite those impacts having the potential for neurological injury. Recent biophysics studies utilizing helmet accelerometers have indicated that athletes at the collegiate and high school levels sustain a surprisingly high number of head impacts ranging from several hundred to well over 1000 during the course of a season. The associated cumulative impact burdens over the course of a career are equally important. Clinical studies have also identified athletes with no readily observable symptoms but who exhibit functional impairment as measured by neuropsychological testing and functional MRI. Such findings have been corroborated by diffusion tensor imaging studies demonstrating axonal injury in asymptomatic athletes at the end of a season. Recent autopsy data have shown that there are subsets of athletes in contact sports who do not have a history of known or identified concussions but nonetheless have neurodegenerative pathology consistent with chronic traumatic encephalopathy. Finally, emerging laboratory data have demonstrated significant axonal injury, blood-brain barrier permeability, and evidence of neuroinflammation, all in the absence of behavioral changes. Such data suggest that subconcussive level impacts can lead to significant neurological alterations, especially if the blows are repetitive. The authors propose “subconcussion” as a significant emerging concept requiring thorough consideration of the potential role it plays in accruing sufficient anatomical and/or physiological damage in athletes and military personnel, such that the effects of these injuries are clinically expressed either contemporaneously or later in life.

Role of venous stenting in the management of inoperable intracranial arteriovenous malformations

29 Nov 2013 12:21 pm


Selective amygdalohippocampectomy versus anterior temporal lobectomy in the management of mesial temporal lobe epilepsy: a meta-analysis of comparative studies

01 Nov 2013 07:31 am


Object Whether selective amygdalohippocampectomy (SelAH) has similar seizure outcomes and better neuropsychological outcomes compared with anterior temporal lobectomy (ATL) is a matter of debate. The aim of this study was to compare the 2 types of surgery with respect to seizure outcomes and changes in IQ scores. Methods PubMed, Embase, and the Cochrane Library were searched for relevant studies published between January 1990 and September 2012. Studies comparing SelAH and ATL with respect to seizure and intelligence outcomes were included. Two reviewers assessed the quality of the included studies and

independently extracted the data. Odds ratios and standardized mean deviations with 95% confidence intervals were used to compare pooled proportions of freedom from seizures and changes in IQ scores between the SelAH and ATL groups. Results Three prospective and 10 retrospective studies were identified involving 745 and 766 patients who underwent SelAH and ATL, respectively. The meta-analysis demonstrated a statistically significant reduction in the odds of seizure freedom for patients who underwent

SelAH compared with those who underwent ATL (OR 0.65 [95% CI 0.51

–0.82], p = 0.0005). The differences between the changes in all IQ scores after the 2 types of surgery were not statistically significant, regardless of the side of resection. Conclusions Selective amygdalohippocampectomy statistically reduced the odds of being seizure free compared with ATL, but the clinical significance of this reduction needs to be further validated by well-designed randomized trials. Selective amygdalohippocampectomy did not have better outcomes than ATL with respect to intelligence.

Spinal epidural haematoma; factors influencing outcome

29 Nov 2013 12:20 pm


Stereotactic radiosurgery used to manage a meningioma filling the posterior two-thirds of the superior sagittal sinus

01 Nov 2013 07:31 am


Intrinsic meningiomas of the superior sagittal sinus pose a significant technical challenge, particularly in the posterior two-thirds of the sinus. Resection is curative but frequently is not possible because of the involvement of critical vascular structures. Here, the authors present the case of a 49-year-old woman with a recurrent meningioma located exclusively in the posterior two-thirds of the sagittal sinus. The patient was treated with a margin dose of 12 Gy and a maximum dose of 24 Gy to the length of the tumor, which measured 16 cm. Five years after treatment, the tumor remains stable and the patient is symptom free. This case demonstrates the unique role that stereotactic radiosurgery can play in the management of meningiomas that are surgically unresectable and have no accepted form of treatment. To the authors' knowledge, 16 cm also represents the longest segment of tumor treated using stereotactic radiosurgery.

Suprasellar tuberculoma

08 Nov 2013 12:35 pm


Surgical embolectomy for large vessel occlusion of anterior circulation

29 Nov 2013 12:20 pm


Temporal bone encephalocele and cerebrospinal fluid fistula repair utilizing the middle cranial fossa or combined mastoid –middle cranial fossa approach

01 Nov 2013 07:30 am


Object The goals of this study were to report the clinical presentation, radiographic findings, operative strategy, and outcomes among patients with temporal bone encephaloceles and cerebrospinal fluid fistulas

(CSFFs) and to identify clinical variables associated with surgical outcome. Methods A retrospective case series including all patients who underwent a middle fossa craniotomy or combined mastoid

–middle cranial fossa repair of encephalocele and/or CSFF between 2000 and 2012 was accrued from 2 tertiary academic referral centers. Results Eighty-nine consecutive surgeries (86 patients, 59.3% women) were included. The mean age at time of surgery was 52.3 years, and the left side was affected in 53.9% of cases. The mean delay between symptom onset and diagnosis was 35.4 months, and the most common presenting symptoms were hearing loss (92.1%) and persistent ipsilateral otorrhea (73.0%). Few reported a history of intracranial infection (6.7%) or seizures (2.2%). Thirteen (14.6%) of 89 cases had a history of major head trauma, 23 (25.8%) were associated with chronic ear disease without prior operation, 17 (19.1%) occurred following tympanomastoidectomy, and 1 (1.1%) developed in a patient with a cerebral aqueduct cyst resulting in obstructive hydrocephalus. The remaining 35 cases (39.3%) were considered spontaneous.

Among all patients, the mean body mass index (BMI) was 35.3 kg/m2, and 46.4% exhibited empty sella syndrome. Patients with spontaneous lesions were statistically significantly older (p = 0.007) and were more

commonly female (p = 0.048) compared with those with nonspontaneous pathology. Additionally, those with spontaneous lesions had a greater BMI than those with nonspontaneous disease (p = 0.102), although this difference did not achieve statistical significance. Thirty-two surgeries (36.0%) involved a middle fossa craniotomy alone, whereas 57 (64.0%) involved a combined mastoid –middle fossa repair. There were 7 recurrences (7.9%); 2 patients with recurrence developed meningitis. The use of artificial titanium mesh was statistically associated with the development of recurrent CSFF (p = 0.004), postoperative wound infection

(p = 0.039), and meningitis (p = 0.014). Also notable, 6 of the 7 cases with recurrence had evidence of intracranial hypertension. When the 11 cases that involved using titanium mesh were excluded, 96.2% of patients whose lesions were reconstructed with an autologous multilayer repair had neither recurrent CSFF nor meningitis at the last follow-up. Conclusions Patients with temporal bone encephalocele and CSFF commonly present with persistent otorrhea and conductive hearing loss mimicking chronic middle ear disease, which likely contributes to a delay in diagnosis. There is a high prevalence of obesity among this patient population, which may play a role in the pathogenesis of primary and recurrent disease. A middle fossa craniotomy or a combined mastoid –middle fossa approach incorporating a multilayer autologous tissue technique is a safe and reliable method of repair that may be particularly useful for large or multifocal defects. Defect reconstruction using artificial titanium mesh should generally be avoided given increased risks of recurrence and postoperative meningitis.

The artery of Davidoff and Schechter: an anatomical study with neurosurgical case correlates

29 Nov 2013 12:21 pm


The evolution of neurosurgery: how has our practice changed?

29 Nov 2013 12:21 pm


The hemodynamic effects during sustained low-efficiency dialysis versus continuous venovenous hemofiltration for uremic patients with brain hemorrhage: a crossover study

01 Nov 2013 07:31 am


Object Hemodynamic instability occurs frequently during dialysis treatment and remains a significant cause of patient morbidity and mortality, especially in patients with brain hemorrhage. This study aims to compare the effects of hemodynamic parameters and intracranial pressure (ICP) between sustained low-efficiency dialysis (SLED) and continuous veno-venous hemofiltration (CVVH) in dialysis patients with brain hemorrhage. Methods End-stage renal disease (ESRD) patients with brain hemorrhage undergoing ICP monitoring were enrolled. Patients were randomized to receive CVVH or SLED on the 1st day and were changed to the other modality on the 2nd day. The ultrafiltration rate was set at between 1.0 kg/8 hrs and

1.5 kg/8 hrs according to the patient's fluid status. The primary study end point was the change in hemodynamics and ICP during the dialytic periods. The secondary end point was the difference between cardiovascular peptides and oxidative and inflammatory assays. Results Ten patients (6 women; mean age

59.9 ± 3.6 years) were analyzed. The stroke volume variation was higher with SLED than CVVH

(generalized estimating equations method, p = 0.031). The ICP level increased after both SLED and CVVH

(time effect, p = 0.003) without significant difference between modalities. The dialysis dose quantification after 8hour dialysis was higher in SLED than CVVH (equivalent urea clearance by convection, 62.7 ± 4.4 vs 50.2 ± 3.9 ml/min; p = 0.002). Additionally, the endothelin-1 level increased after CVVH treatment (p =

0.019) but not SLED therapy. Conclusions With this controlled crossover study, the authors provide the pilot evidence that both SLED and CVVH display identical acute hemodynamic effects and increased ICP after dialysis in brain hemorrhage patients. Clinical trial registration no.: NCT01781585 (ClinicalTrials.gov).

The impact of radiosurgery fractionation and tumor radiobiology on the local control of brain metastases

01 Nov 2013 07:31 am


Object Experience with whole-brain radiation therapy for metastatic tumors in the brain has identified a subset of tumors that exhibit decreased local control with fractionated regimens and are thus termed radioresistant. With the advent of frameless radiosurgery, fractionated radiosurgery (2

–5 fractions) is being

used increasingly for metastatic tumors deemed too large or too close to crucial structures to be treated in a single session. The authors retrospectively reviewed metastatic brain tumors treated at 2 centers to analyze the dependency of local control rates on tumor radiobiology and dose fractionation. Methods The medical records of 214 patients from 2 institutions with radiation-naive metastatic tumors in the brain treated with radiosurgery given either as a single dose or in 2 –5 fractions were analyzed retrospectively. The authors compared the local control rates of the radiosensitive with the radioresistant tumors after either singlefraction or fractionated radiosurgery. Results There was no difference in local tumor control rates in patients receiving single-fraction radiosurgery between radioresistant and radiosensitive tumors (p = 0.69). However, after fractionated radiosurgery, treatment for radioresistant tumors failed at a higher rate than for radiosensitive tumors with an OR of 5.37 (95% CI 3.83

–6.91, p = 0.032). Conclusions Single-fraction radiosurgery is equally effective in the treatment of radioresistant and radiosensitive metastatic tumors in the brain. However, fractionated stereotactic radiosurgery is less effective in radioresistant tumor subtypes.

The authors recommend that radioresistant tumors be treated in a single fraction when possible and techniques for facilitating single-fraction treatment or dose escalation be considered for larger radioresistant lesions.

The impact of smoking on neurosurgical outcomes

01 Nov 2013 07:31 am


Cigarette smoking is a common health risk behavior among the general adult population, and is the leading preventable cause of morbidity and mortality in the US. The surgical literature shows that active tobacco smoking is a major risk factor for perioperative morbidity and complications, and that preoperative smoking cessation is an effective measure to lower these risks associated with active smoking. However, few studies have examined the effects of smoking and perioperative complications following neurosurgical procedures.

The goal of this review was to highlight the scientific data that do exist regarding the impact of smoking on neurosurgical outcomes, to promote awareness of the need for further work in the specific neurosurgical context, and to suggest ways that neurosurgeons can promote smoking cessation in their patients and lead efforts nationally to emphasize the importance of preoperative smoking cessation. This review indicates that there is limited but good evidence that smoking is associated with higher rates of perioperative complications following neurosurgical intervention. Specific research is needed to understand the effects of smoking and perioperative complications. Neurosurgeons should encourage preoperative smoking cessation as part of their clinical practice to mitigate perioperative morbidity associated with active smoking.

The relationship between the superior petrosal sinus and the porus trigeminus: an anatomical study

01 Nov 2013 07:31 am


Object During intracranial approaches to the skull base, vascular relationships are important. One relationship that has received scant attention in the literature is that between the superior petrosal sinus

(SPS) and the opening of the Meckel cave (that is, the porus trigeminus). Methods Cadaver dissections were performed in 25 latex-injected adult cadaveric heads (50 sides). Specifically, the relationship between the SPS and the opening of the Meckel cave was observed. The goal was to enhance knowledge of the relationship between the SPS and the opening of the Meckel cave. Results Of the 50 sides, 68%, 18%, and

16% of SPSs traveled superior to, inferior to, and around the opening to the Meckel cave, respectively. In the latter cases, a venous ring was formed around the proximal trigeminal nerve. No sinus entered the

Meckel cave. In general, the porus trigeminus was narrowed on sides found to have an SPS that encircled this region. Sinuses that traveled only inferior to the porus were in general smaller than sinuses that traveled superior or encircled this opening. No statistically significant differences were noted between the various sinus relationships and sex, age, or side of the head. Conclusions Knowledge of the relationship between the SPS and the opening of the Meckel cave may be useful to the skull base surgeon. Based on this study, some individuals may retain the early embryonic position of their SPS in relation to the trigeminal nerve.

The use of the nasoseptal flap to reduce the rate of post-operative cerebrospinal fluid leaks following endoscopic trans-sphenoidal surgery for pituitary disease

29 Nov 2013 12:21 pm


The utility of calcium phosphate cement in cranioplasty following retromastoid craniectomy for cranial neuralgias

29 Nov 2013 12:20 pm


Transsylvian hippocampal transection for mesial temporal lobe epilepsy: surgical indications, procedure, and postoperative seizure and memory outcomes

01 Nov 2013 07:31 am


Object Amygdalohippocampectomy is a well-established, standard surgery for medically intractable mesial temporal lobe epilepsy (MTLE). However, in the case of MTLE without hippocampal atrophy or sclerosis, amygdalohippocampectomy is associated with decreased postoperative memory function. Hippocampal transection (HT) has been developed to overcome this problem. In HT the hippocampus is not removed; rather, the longitudinal hippocampal circuits of epileptic activities are disrupted by transection of the pyramidal layer of the hippocampus. The present study describes a less invasive modification of HT

(transsylvian HT) and presents the seizure and memory outcomes for this procedure. Methods Thirty-seven patients with MTLE (18 men and 19 women; age range 9

–63 years; 19 with surgery on the right side and 18 with surgery on the left side; seizure onset from 3 to 34 years) who were treated with transsylvian HT were retrospectively analyzed. All patients had left-side language dominance, and follow-up periods ranged from

12 to 94 months (median 49 months). Seizure outcomes were evaluated for all patients by using the Engel classification. Memory function was evaluated for 22 patients based on 3 indices (verbal memory, nonverbal memory, and delayed recall), with those scores obtained using the Wechsler Memory Scale –Revised.

Patients underwent evaluation of the memory function before and after surgery (6 months –1 year). Results

Engel Class I (completely seizure free) was achieved in 25 patients (67.6%). Class II and Class III designation was achieved in 10 (27%) and 2 patients (5.4%), respectively. There were differences in memory outcome between the sides of operation. On the right side, verbal memory significantly increased postoperatively (p = 0.003) but nonverbal memory and delayed recall showed no significant change after the operation (p = 0.718 and p = 0.210, respectively). On the left side, all 3 indices (verbal memory, nonverbal memory, and delayed recall) showed no significant change (p = 0.331, p = 0.458, and p = 0.366, respectively). Conclusions Favorable seizure outcome and preservation of verbal memory were achieved with transsylvian HT for the treatment of MTLE without hippocampal atrophy or sclerosis.

Tumor volume as a predictor of survival and local control in patients with brain metastases treated with Gamma Knife surgery

01 Nov 2013 07:31 am


Object The aim of this study was to examine tumor volume as a prognostic factor for patients with brain metastases treated with Gamma Knife surgery (GKS). Methods Two hundred fifty patients with 1 –14 brain metastases who had initially undergone GKS alone at a single institution were retrospectively reviewed.

Patients who received upfront whole brain radiation therapy were excluded. Survival times were estimated using the Kaplan-Meier method. Univariate and multivariate analyses using Cox proportional hazard regression models were used to determine if various prognostic factors could predict overall survival, distant brain failure, and local control. Results Median overall survival was 7.1 months and the 1-year local control rate was 91.5%. Median time to distant brain failure was 8.0 months. On univariate analysis an increasing total tumor volume was significantly associated with worse survival (p = 0.031) whereas the number of brain metastases, analyzed as a continuous variable, was not (p = 0.082). After adjusting for age, Karnofsky

Performance Scale score, and extracranial disease on multivariate analysis, total tumor volume was found to be a better predictor of overall survival (p = 0.046) than number of brain metastases analyzed as a continuous variable (p = 0.098). A total tumor volume cutoff value of ≥ 2 cm3 (p = 0.008) was a stronger predictor of overall survival than the number of brain metastases (p = 0.098). Larger tumor volume and extracranial disease, but not the number of brain metastases, were predictive of distant brain failure on multivariate analysis. Local tumor control at 1 year was 97% for lesions < 2 cm3 compared with 75% for lesions ≥ 2 cm3 (p < 0.001). Conclusions After adjusting for other factors, a total brain metastasis volume was a strong and independent predictor for overall survival, distant brain failure, and local control, even when considering the number of metastases.

Use of near-infrared indocyanine videoangiography and Flow 800 in the resectioning of a

spinal cord haemangioblastoma

29 Nov 2013 12:20 pm


Use of the anterior interosseous artery for external to internal carotid artery bypass procedures: a cadaveric feasibility study

29 Nov 2013 12:20 pm


What does it take to deliver an international neurosurgical trial? Experiences from STICH II

11 Nov 2013 12:00 pm


Talk to us about our bulletins!

We'd love to hear what you think of this bulletin. Is it too vague? Too specific? Spot on? Is it doing the job or missing the mark?

Is there a resource we've missed out? Do you need a bulletin on a different topic?

Please let us know (contact details above) so that we can provide you with a better service! We currently have bulletins on the following topics, available weekly or monthly, by email or post:

A & E Haematology Patient Safety & Clinical Risk

Anaesthesia

Brain Injury

Health Psychology

Heart Failure

Physiotherapy

Plastic & Reconstructive Surgery

Breast Care

CAMHS

Cardiology

Care of the elderly

Continence

Critical Care Nursing

Dementia

Diabetes

Dietetics

End-of-life Care

Management & Quality

Medical Education

Mental Health Commissioning

Mental Health Nursing

Neurosurgery

Obstetrics & Gynaecology

Oncology

Ophthalmology

Paediatric Burns

Paediatrics

Primary Care

Psychodynamics

Public Health

Renal Care

Renal Nursing

Safeguarding Children

Sexual Health

Substance Misuse

Vascular Surgery

Wound Care

ENT

Copyright © 2013 North Bristol NHS Trust Library & Information Service, All rights reserved.

You are receiving this email because you opted in via the library service at Frenchay, Southmead or South

Plaza.

Our mailing address is:

North Bristol NHS Trust Library & Information Service

1st Floor, Learning & Research, Southmead Hospital

Westbury-on-Trym

Bristol, Eng BS10 5NB

United Kingdom

Add us to your address book unsubscribe from this list update subscription preferences

For more information on accessing electronic

Library & Information Service

Latest News Bulletin

- Neurosurgery -

Related documents

Products

Support

For more information on accessing electronic

Library & Information Service

Latest News Bulletin

- Neurosurgery -

Related documents

Add this document to collection(s)

Add this document to saved

Suggest us how to improve StudyLib