GENERAL
Jorge E. Alvernia, MD
Microsurgical Laboratory,
Department of Neurosurgery,
Tulane University,
New Orleans, Louisiana; and
Pierre Wertheimer Neurological and
Neurosurgical Hospital,
Anatomy Department,
Claude Bernard University Lyon,
Lyon, France
Gustavo Pradilla, MD
Microneurosurgery Laboratory,
Department of Neurosurgery,
The Johns Hopkins University
School of Medicine,
Baltimore, Maryland
Patrick Mertens, MD
Pierre Wertheimer Neurological and
Neurosurgical Hospital,
Anatomy Department,
Claude Bernard University Lyon,
Lyon, France
Giuseppe Lanzino, MD
Microsurgical Laboratory,
Department of Neurosurgery,
University of Illinois at Peoria,
Peoria, Illinois; and
Department of Neurologic Surgery,
Mayo Clinic,
Rochester, Minnesota
Surgical Anatomy and Technique
Latex Injection of Cadaver Heads: Technical Note
BACKGROUND: Latex injection of cadaveric heads is an alternative to the standard
technique of silicone injection. Thorough injections of the arterial and venous systems
can be achieved by analyzing the anatomic and physiological variations of the vascular
system of each specimen during the initial irrigation phase to tailor the subsequent latex
injection.
OBJECTIVE: To report on an improved method for color latex injection of cadaveric
specimens using these techniques.
METHODS: Thirty-two cadaver heads were injected and preserved for anatomic dissection. The critical steps included (1) cannulation of the cervical arteries and veins with
Foley or Coude catheters, (2) ‘‘indirect’’ anatomic study of the vasculature during irrigation with water of the major arteries and veins, (3) fixation of the specimen with either
formaldehyde or alcohol, and (4) color injection of the arteries and veins with red and
blue latex, respectively. The injected specimens were dissected and assessed qualitatively for the extent and detail of arterial and venous filling. Assessment and recording of
flow characteristics from the specimens during water irrigation of the arterial and venous
systems dictated the order and technique for subsequent latex injections.
RESULTS: Latex injections resulted in deeper penetration of colored solutions into small
cerebral vessels and mesenchymal structures. Of 32 injected specimens, 25 (78%) had
outstanding injections and 7 (21.8%) had suboptimal results. Latex solutions are simpler
to use than silicone solutions.
CONCLUSION: Latex injection of cadaveric heads based on indirect anatomic and
physiological assessment of the vasculature of the specimen during the water irrigation
phase results in outstanding specimens for microanatomical studies.
KEY WORDS: Cadaver, Dissection, Injection, Latex
Rafael J. Tamargo, MD
Microneurosurgery Laboratory,
Department of Neurosurgery,
The Johns Hopkins University
School of Medicine,
Baltimore, Maryland
Reprint requests:
Rafael J. Tamargo, MD, FACS,
Walter E. Dandy Professor of
Neurosurgery,
Director Cerebrovascular Neurosurgery,
The Johns Hopkins University School of
Medicine,
Department of Neurosurgery,
Meyer Bldg,
Ste 8-181,
600 N Wolfe St,
Baltimore, MD 21287.
E-mail: rtamarg@jhmi.edu
Neurosurgery 67[ONS Suppl 2]:ons362–ons367, 2010
A
precise understanding of cerebral anatomy is fundamental in neurosurgical
training and practice. Neurosurgical
training, neuroanatomical research, and novel
neurosurgical techniques depend on the detailed
study of cadaveric specimens. Adequate preparation of cadaveric specimens for dissection
requires tailored tissue fixation protocols and
substitution of in vivo coloration and flow
characteristics with artificial markers to properly
differentiate arterial and venous structures.
Colored injection of the arterial and venous
systems of cadaveric heads provides precise
Received, September 16, 2009.
Accepted, June 4, 2010.
Copyright ª 2010 by the
Congress of Neurological Surgeons
ABBREVIATIONS: CCA, common carotid artery; IJV,
internal jugular vein; PCOM, posterior communicating artery; VA, vertebral artery
ons362 | VOLUME 67 | OPERATIVE NEUROSURGERY 2 | DECEMBER 2010
DOI: 10.1227/NEU.0b013e3181f8c247
anatomic detail of the cerebral vasculature essential for microanatomical studies.
Although most published reports of cadaveric
brain injections use silicone as the standard agent,
colored latex solutions can provide additional
benefits with the advantage of reducing complexity. Latex solutions are commercially available preparations with predictable resistance,
high penetration through small distal vessels, fast
consolidation times, and low cost, which make
them ideal candidates for cadaveric injections.
Furthermore, given that anatomic variability of the
arterial and venous systems, as well as postmortem
thrombotic obstructions, may impair the injection
of latex, it is important to study flow physiology
in each specimen before the final injection.
We describe a novel technique of colored latex
injections of cadaveric specimens that takes into
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LATEX INJECTION OF CADAVER HEADS
consideration preinjection anatomic and physiological assessment
of vascular flow and results in high-quality specimens for anatomic microdissection.
METHODS
Procurement of Cadaver Heads
Thirty-two cadaver heads were obtained in accordance with the
Departments of Health and Mental Hygiene or equivalent regulatory
agencies of Lyon, France; Peoria, Illinois; and Baltimore, Maryland,
where the injections and dissections were performed. Twenty fresh
nonfrozen specimens and 12 fresh-frozen specimens were used. Special
care was taken in requesting nonfixed heads rather than frozen heads
unless freezing was required for shipping purposes. All specimens injected in Lyon were available immediately after death, which precluded
the need for fixation.
Colored Latex Solutions
Red and blue latex solutions were obtained from Ward’s Natural
Science, Rochester, New York (latex injection medium, blue, laboratory,
1-L bottle [catalog No. 37 V 2576] or red [catalogue No. 37 V 2571]).
Cannulation of the Cervical Arteries and Veins
Cervical vessels were identified and dissected to isolate 1.5 to 2 cm of
each vessel from the surrounding soft tissue; the tips of 1-way silicone
Foley catheters (5-cm3 inflatable balloon, Rochester Medical, Stewartville, Minnesota) were cut at a 45 angle while preserving the balloon and
used to cannulate the vessels. Whereas other investigators have recommended suction tubing, intravenous tubing, ventriculostomy catheters,
chest tubes, nasogastric tubes, or large-bore intravenous catheters,1 we
prefer 1-way Foley or red rubber Coude-tip (Coude, 5-cm3 inflatable
balloon, BARD Medical, Covington, Georgia) urinary catheters for
several reasons: Foley and Coude-tip catheters are available in sizes
ranging from 8F to 32F; pediatric Foley catheters (8F) are best for small
arteries; Foley catheters have adequate stiffness to cannulate the vessels
but enough flexibility to allow manipulation; and the balloon of the
catheters can be used to occlude the vessel and to prevent backflow of
latex during injection.
The order of vessel cannulation proceeds as follows. The common
carotid arteries (CCAs) are identified first and cannulated with 20F to
24F Foley catheters inserted 2 to 3 cm into the vessel. Next, the internal
jugular veins (IJVs) are identified distally in the neck and cannulated
with 20F to 36F Foley catheters. Placement of the tip of this catheter as
high into the jugular bulb as possible is advantageous because it prevents
the injected colored latex from filling extracranial tributaries before
entering the intracranial compartment. This can be achieved by placing
the tip of the catheter at the level of the external auditory meatus. The
vertebral arteries (VAs) are then identified, dissected from the foramina
transversaria, and cannulated with 12F to 18F Foley catheters. The
catheters are secured to the vessels with 2-0 silk sutures to ensure
a watertight seal and to prevent accidental displacement. The largest
possible catheter should be used to minimize resistance to injection and
to prevent backflow in subsequent steps.
variants of the arterial and venous systems. This is performed manually
with warm tap water using a 60-cm3 syringe or directly from the tap by
connecting clear plastic tubing to each catheter. The clear tubing
facilitates monitoring of the water level and assessment of the pressure
within the system.
The arterial system is irrigated before the venous system because
venous congestion may lead to increased resistance and decreased arterial
flow. The venous system has high capacitance, and irrigation without
previous arterial flushing can result in congestion of the venous sinuses
and intracranial veins, which increases resistance within the arterial
system, prevents adequate removal of clot and debris, and decreases
effective dilation of distal arteries. The following irrigation sequence is
therefore critical: the CCAs first, the VAs second, the dominant IJV
(usually on the right side) third, and finally the nondominant IJV.
Intracranial venous congestion can be assessed during irrigation by
observing the outflow of water from the spinal canal, which indicates
flow through the arachnoid granulations and subarachnoid space. Pulsations observed in the spinal cord during irrigation directly reflect the
transmitted pressure, and sudden displacement of the spinal cord indicates herniation of the brain, which can occur during aggressive irrigation, particularly of unfixed specimens. Similarly, the water meniscus
in the spinal canal can be used as an indirect measure of intracranial
pressure. Obliteration of the spinal canal with bone wax precludes these
observations and therefore is not recommended.1 If flow from other
cervical vessels such as an accessory jugular vein is detected, these vessels
should be ligated.
Indirect Assessment of the Vasculature
During irrigation, key anatomic observations are made to determine
patency and to anticipate resistance in the arterial system. The anatomic
configuration of the circle of Willis is assessed by selectively testing its
patency as follows: If irrigation of 1 CCA results in flow from the
contralateral CCA, then the A1 segments are patent and an anterior
communicating artery is present. If irrigation of a CCA results in flow
from the VAs, then a patent ipsilateral posterior communicating artery
(PCOM) is present. Conversely, the PCOMs are patent if irrigation of
the VAs results in flow from the CCAs.
Regulation of water flow by selective vessel clamping during water
irrigation helps to dilate portions of the arterial system and to open
potential anastomoses. During irrigation of the left CCA, the right CCA
catheter is intermittently clamped to promote flow through the PCOM
into the vertebrobasilar system. Similarly, during irrigation of 1 VA, it is
important to clamp the contralateral VA to promote flow into the basilar
artery and through the PCOMs into the carotid system. Correspondingly, during irrigation of the venous system, each jugular vein catheter
is intermittently closed to evaluate for any potential leaks through the
external jugular or superficial venous systems.
Irrigation should be continued until the water flow is clear, which
ensures that clots and debris have been removed. The amount of irrigation used, usually 2 to 4 L, depends on the amount of clot and debris
within the vasculature. Specimens that have been previously fixed will
often require larger amounts of irrigation because of retained clots. For
each specimen, the flow and anastomotic connections observed during
irrigation must be recorded to guide the subsequent latex injection.
Irrigation of the Arterial and Venous Systems
Formaldehyde or Alcohol Fixation
Although irrigation of the vasculature with tap water is performed
primarily to remove clots and debris, this step also reveals the anatomic
After water irrigation, fixation can be accomplished with either
formaldehyde (formaldehyde 37% in H2O, Sigma-Aldrich, St. Louis,
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ALVERNIA ET AL
Missouri) or ethyl alcohol (200 proof, anhydrous, Sigma-Aldrich). For
selective fixation of the brain parenchyma, perfusion with formaldehyde for
2 days is recommended. Brain stiffness can be increased with increasing
concentrations of formaldehyde, beginning at 10% and increasing to 20%
and 37%. If preservation of the muscle, nerves, and skin is preferred for
anatomic studies, ethyl alcohol provides superior preservation.
Initially, a mixture of formaldehyde 37% and ethyl alcohol 10% is
injected into the cannulated arteries and veins. Following the water
irrigation protocol, CCAs are injected first, followed by the VAs and
finally by the IJVs. After injection, the catheters are closed to maintain
the fixation solution within the vasculature for 48 to 72 hours. The head
is then partially immersed in a closed container on a mixture of 10%
formaldehyde and 10% ethyl alcohol for as long as the specimen remains
in use and kept refrigerated at 4C. Most specimens will remain in good
condition even 4 years after fixation. Lower concentrations of formaldehyde (ie, 2%) may prolong fixation time, requiring up to 4 weeks to
obtain the desired consistency. Adequate preservation of the cerebellum
requires the longest fixation period.
Colored Latex Injection of the Arterial and
Venous Systems
After fixation is completed, the Foley catheters are opened and the
vessels are flushed again with room-temperature water to reassess vascular
permeability before the colored latex injection. Colored-latex solutions
are commercially available (Ward’s Natural Science, Rochester, New
York) in liquid form and consist of latex powder 62%, ammonium
hydroxide 7%, and water 31%, with a specific gravity of 0.95 g/mL at
20C. The density of the solution is ideal for injection, but increased
penetration of smaller structures can be achieved by additional dilutions
with water. The CCAs are injected first with a 60-cm3 syringe with red
latex. As soon as flow is seen out of the contralateral CCA, this vessel is
clamped and steady pressure is applied through the ipsilateral CCA to
promote flow into the PCOMs toward the vertebrobasilar system. After
flow from the VAs is obtained, an additional 10 mL latex is injected and
all arterial Foley catheters are quickly closed. After 5 minutes, the
catheters are unclamped and the process is repeated for the contralateral
carotid and the VAs (Figure 1).
During the latex injection, it is important to replicate the flow obtained during the water irrigation phase for optimal results. This may
require forceful injection while the contralateral CCA is clamped to open
the PCOM. Likewise, injection of the VAs may require intermittent
clamping of the contralateral VA to promote flow across to the anterior
circulation. If such anastomotic flow could not be obtained during the
irrigation steps, then it is unlikely to be observed during the injection phase.
During this step, forceful injection of the latex solution can result in rupture
of small distal arteries, veins, and capillaries. Observation of the transmitted
pressure onto the spinal cord (craniocaudal displacement within the spinal
canal) and direct feedback from the injection syringe are used to minimize
these events; however, adequate water irrigation is the most important
factor to avoid applying unnecessary pressure because retained clots are the
main cause of high resistance during the injection phase.
After injection of the arterial system, the adequacy of color injection
can be verified by making a small 1-cm skin incision over the parietal
eminence, which is the most distal site of blood flow from the external
carotid artery, to confirm that small end arteries in the scalp have been
filled.
The venous system is then injected with blue latex solution. A larger
volume of latex is needed for this injection because the larger capacitance
ons364 | VOLUME 67 | OPERATIVE NEUROSURGERY 2 | DECEMBER 2010
of the venous system. A 60-cm3 syringe with blue latex is attached to the
Foley catheter of the dominant jugular vein, and the venous system is
filled until flow out of the contralateral jugular vein is seen. Both Foley
catheters are then clamped and the procedure is repeated with the
contralateral jugular vein. After injection of both jugular veins, the
catheters are closed and the balloons in each catheter are inflated to
encourage further flow of latex into the venous system. Observation of
small venules through the parietal scalp incision made after the arterial
injection reflects the quality of the venous injection. Alternatively, an
optimal venous injection can also be detected by a blue discoloration of
the oral and labial mucosa.
A postinjection settling period is important before use, and although
some investigators have reported that 24 hours may suffice,2-4 we concur
with Tubs et al,4 who recommend a 36-hour waiting period. For cases in
which latex dilution with water was necessary to improve distal penetration, a 72-hour period is advised before the dissection is started.
Evaluation of Injected Specimens
The quality of the injected specimens was evaluated and scored on
the basis of the penetration of colored latex into cortical capillaries, the
consistency of the vessels during dissection, and the presence of latex
extravasation in the subarachnoid space.
RESULTS
Colored latex injections resulted in deeper penetration of
colored solutions into small cerebral vessels and mesenchymal
structures. Of 32 injected specimens, 25 (78%) had outstanding
injections and 7 (21.8%) had suboptimal results. Latex solutions
were simpler to use than silicone solutions.
DISCUSSION
Latex is an excellent alternative to silicone for color injection of
cadaveric brains because of its predictable resistance, deep penetration into small distal vessels, and faster consolidation and
hardening times. It does not require mixing, as is the case with
silicone, and has standardized resistance with predictable hardening times. Hardening times and resistance to flow during
silicone injections can be difficult to predict and can add unnecessary complexity to the injection process. Furthermore,
colored latex is available in a ready-to-use form, which precludes
the need for preinjection preparation. In our experience, colored
latex solutions are easier to prepare and deliver than silicone-based
solutions, and colored latex injections result in anatomic specimens comparable to those obtained after silicone injections
(Figures 2 and 3).
Selective injection of the cerebral vasculature was first documented by Thomas Willis (1621-1675) in the 17th century.5 In
his book Cerebri Anatome, cui accessit Nervorum descriptio et usus
(Anatomy of the Brain, With a Description of the Nerves and Their
Function) published in 1664, Willis described for the first time
details of the arterial system of the brain. By selectively ligating
different parts of the ‘‘circle,’’ he demonstrated that blood flow
could still reach the contralateral hemisphere through anastomotic connections of the circulus arteriosus.6
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LATEX INJECTION OF CADAVER HEADS
FIGURE 1. Artistic illustration of the technique of cadaveric injection. Injection procedure: Once the 6 vascular access ports
(both internal carotid arteries, both internal jugular veins, and both vertebral arteries) have been cannulated with Foley catheters
and copiously irrigated with warm water, we inject the latex, starting with the arterial system, followed by the venous system. At
this time, a good understanding of the anatomy of the circle of Willis is usually achieved, which improves the results of the
injection. Of paramount importance is the continuous monitoring of the spinal canal, which conveys the intracranial pressure
during the injection of the colorant material. Overlooking this step may result in unnoticed loss of brain tissue through the foramen
magnum and subsequently through the subdural space surrounding the spinal cord.
Color injection of the cerebral vasculature is now commonly
performed to improve the quality of anatomic detail of cadaver
specimens for neurosurgical research and education.7-9 With
modern microsurgical techniques, color injection is necessary to
provide the anatomic detail that is encountered in the operating
NEUROSURGERY
room. Few reports in the literature specifically address the
techniques for color injection of cadaveric specimens,7-10 and
disagreement regarding the optimal injection techniques remains.
Different materials have been used for cadaveric injections,
ranging from natural rubber to resins such as Bakelite and silicone
VOLUME 67 | OPERATIVE NEUROSURGERY 2 | DECEMBER 2010 | ons365
Copyright © Congress of Neurological Surgeons. Unauthorized reproduction of this article is prohibited.
ALVERNIA ET AL
FIGURE 2. Sylvian fissure injection. Special preparation
aimed to obtain optimal texture of the brain parenchyma
and adequate penetration of the distal vascular branches of
the middle cerebral artery.
(Schummer 1935).11,12 Other materials such as gelatin have also
been proposed, although the required boiling process and its poor
flexibility are drawbacks to this technique.13
In 1999, Sanan and colleagues1 described their technique for
cadaveric silicone injections at the University of Cincinnati. In
comments following that report, Day and Rhoton also described
their technique, which does not differ substantially from that of
Sanan et al and uses silicone.
The literature on cadaveric latex injection of veins is scarce, but
authors such as Groen et al14 have used it to inject the anterior
and posterior internal vertebral venous plexus in human fetuses
between 21 and 25 weeks of gestational age because of its excellent penetration into small vessels. For this group, at least 2
weeks of fixation with 4% formaldehyde in phosphate-buffered
saline (room temperature; pH = 7.4) was necessary for correct
fixation of the tissue and solidification of the latex. A study by
Palombi et al15 highlighted the transversovertebral venous sinus
around the extracranial segments of the VA using latex and
further illustrated the benefits of this technique. Furthermore,
Tubbs et al2 and Schmidt and Lorthioir10 also demonstrated the
intricate venous anatomy of the marginal sinus and the basilar
plexus with latex.
Recent peripheral nerve studies on the arterial penetration of
latex have shown the value of this technique for visualization of
microvascular anatomy.4,13 Other materials such as gelatin-lead
oxide and Chinese ink, however, are superior in terms of delineating the detailed anatomy of these structures.13
Our injection method relies on a physiological assessment of
flow in the arterial and venous systems. During the irrigation
phase, observations are made regarding the flow through the
posterior and anterior circulations, which will then be replicated
during the injection phase. In addition, different vessels are closed
and opened to promote flow through the entire arterial system
during the irrigation phase. The same techniques are then applied
to color injection of the arterial and venous systems with latex
solutions to ensure that the entire vasculature is filled. We believe
that close observation of physiological flow through the vasculature in each cadaveric specimen during each stage is vital to
obtain optimal results.
CONCLUSION
We report an alternative to silicone and an improved method
for color injection of cadaver heads using colored latex solutions
based on an assessment of the physiology of flow within the
cerebral vasculature during the different stages of the procedure.
This technique has led to superior results in the preparation of
cadaveric specimens for anatomic dissection.
Disclosure
The authors have no personal financial or institutional interest in any of the
drugs, materials, or devices described in this article.
REFERENCES
FIGURE 3. Occipital artery injection. Special preparation
aimed to obtain optimal muscle preservation and good distal
injection of the occipital artery branches, which are not
typically identified with conventional 4-vessel angiography.
ons366 | VOLUME 67 | OPERATIVE NEUROSURGERY 2 | DECEMBER 2010
1. Sanan A, Abdel Aziz KM, Janjua RM, van Loveren HR, Keller JT. Colored
silicone injection for use in neurosurgical dissections: anatomic technical note.
Neurosurgery. 1999;45(5):1267-1271; discussion 1271-1274.
2. Tubbs RS, Ammar K, Liechty P, et al. The marginal sinus. J Neurosurg.
2006;104(3):429-431.
3. Tubbs RS, Hansasuta A, Loukas M, et al. The basilar venous plexus. Clin Anat.
2007;20(7):755-759.
4. Tubbs RS, O’Neil JT Jr, Key CD, et al. Superficial temporal artery as an external
landmark for deeper-lying brain structures. Clin Anat. 2007;20(5):498-501.
5. Puget. Histoire des Techniques de Preparation et de Conservation des Pieces Anatomiques dans un but Medical. Lyon-Nord, France: Faculte de Medecine, Universite
Claude Bernard; 1982.
6. Goodrich JT. A millennium review of skull base surgery. Childs Nerv Syst.
2000;16(10-11):669-685.
7. Latarjet M. Plastics in anatomical technique [in French]. Sem Med. 1952;28(74):10.
8. Latarjet M, Douroux PE, Juttin P. Use of plastic material in anatomical technic;
anatomo-pathological aspects [in French]. Lyon Chir. 1952;47(4):467-470.
www.neurosurgery-online.com
Copyright © Congress of Neurological Surgeons. Unauthorized reproduction of this article is prohibited.
LATEX INJECTION OF CADAVER HEADS
9. Latarjet M, Juttin P. Use of injections of plastic substances in anatomopathological
studies of the lung [in French]. Poumon. 1952;8(5):459-463.
10. Schmidt C, Lorthioir J. Injection with plastic materials of the different vascular
systems [in French]. Arch Mal Coeur Vaiss. 1950;43(3):274-278.
11. Bouchet A. The embalming and preservation of human cadavers over the centuries
[in French]. Lyon Med. 1972;227(1):9-20.
12. Poules J. Preparation of anatomic pieces in plastic materials. Presse Med.
1953;61(16):327.
13. Peng TH, Ding HM, Chen SH, et al. Demonstration of three injection methods
for the analysis of extrinsic and intrinsic blood supply of the peripheral nerve. Surg
Radiol Anat. 2009;31(8):567-571.
14. Groen RJ, Grobbelaar M, Muller CJ, et al. Morphology of the human internal
vertebral venous plexus: a cadaver study after latex injection in the 21-25-week
fetus. Clin Anat. 2005;18(6):397-403.
15. Palombi O, Fuentes S, Chaffanjon P, Passagia JG, Chirossel JP. Cervical venous
organization in the transverse foramen. Surg Radiol Anat. 2006;28(1):66-70.
Acknowledgment
We would like to acknowledge Dr Marc Sindou, MD, Professor
of Neurosurgery at the University of Lyon, for his contribution to
the improvement of the microsurgical techniques applied to the
cadaver dissections throughout the time this study was performed.
COMMENTS
preparation vs silicon injection. I found, as did the authors, latex to be
superior to silicone for color injection of cadaveric brains because of its
predictable resistance, greater filling of small distal vessels, and faster
consolidation/hardening times.
I also agree with the authors that an optimal injection preparation
relies on a physiological assessment of flow in the arterial and venous
systems. As the authors stated, the initial phase of irrigation is of paramount importance to clear the intracranial vasculature of blood clots
and to allow subsequent optimal latex injection. In our laboratory, we
use instead a very low concentration of formaldehyde (1%) mixed with
ethyl alcohol for our fixation solution. Such a low concentration of
formaldehyde lowers health issues while working on hours-long dissection and avoids the bothersome brain stiffness during skull base
procedures. We prefer adding glycerin to the solution to be able to adjust
brain consistency. In addition, during the injection phase, properly
closing and opening the vessels will guarantee optimal filling of the
intracranial vasculature. We are usually careful not to apply too much
pressure when injecting the latex, particularly when the goal of our
dissection is a thorough study of venous plexuses such as the cavernous
sinus. Forceful injection may provoke false anatomical findings, breaking
up thin-walled vessels like the one in venous plexuses. We usually wait
48 hours to allow the latex to consolidate before using the specimen for
dissection. This meticulous technique of fixation and injection, when
applied properly, provides optimal injection of fine vessels and mimics
the condition of the brain and soft tissue as closely as possible.
Antonio Bernardo
New York, New York
A
lvernia et al have presented a detailed, nicely illustrated technical
note that specifies the optimal preparation technique for injection
of cadaveric specimens. The cadaver dissection laboratory environment is
the ideal training arena to teach neurosurgeons and residents the visuospacial skills required to navigate through various neurosurgical approaches. There is no substitute for diligent practice of surgical dissection
techniques in the laboratory setting. Surgical exercises provide adequate
preoperative training and rehearsal of complex neurosurgical approaches.
Such surgical exercises are performed on cadaveric specimens under
conditions that simulate an actual operation as closely as possible. Proper
preparation of the specimens is of paramount importance to achieve
conditions as close as possible to a real scenario. The authors provide
a precise and detailed, step-by-step technique for preparing specimens for
surgical dissections. I have been using latex injection and a very similar
preparation technique since 1997 and have since used latex injection in
several hundred specimens as a preferred method of specimen
NEUROSURGERY
A
lvernia et al report an improved method for color injection of
cadaver heads using colored latex solutions. The assessment is based
on the physiology of flow within the cerebral vasculature during the
different stages of the procedure. They reiterate that it is superior to
silicone in preparation of cadaveric specimens for anatomic dissection.
The manuscript is well written and the technique well discussed. The
injection methods and the flow mechanics within the cerebral vasculature are discussed elaborately. The figures are lucid and depict the detailed intracranial and extracranial vascular network. This work provides
stimulation for other authors to use colored latex solutions for the
preparation of cadaveric specimens.
Dattatraya Muzumdar
Mumbai, India
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