Vascular lesions of the CNS, also known as
cerebral cavernous malformations or
angiographically-occult arterio-venous
malformations
Represent a surgically correctable cause of
epilepsy in the paediatric population
• KM. 9 year old boy
• New onset complex partial seizures with right frontal
discharges
• Seizure activity well-controlled on sodium valproate,
levetiracetam, and carbamazepine
• Imaging suggested cavernoma
Craniotomy & Excision
Mesh of thick walled vessels
Peri-lesional Haemosiderin
Lumen
Possible rupture point
• MS. 9 year old male
• New onset complex partial seizures with right frontal
discharges
• Seizure activity well-controlled on sodium valproate,
levetiracetam, and carbamazepine
• Imaging suggested cavernoma
• Follow – Up
– Seizure frequency ↓
– No deficit
• MK. 10 year old girl
• 8 month hx of simple & complex partial seizures
secondary to right tempero-parietal lesion
• Failed multiple single & combination anti-convulsants
failed
– Side – effects
– Fatigue & Poor school performance
• Imaging
Stealth-guided parietal craniotomy
en-bloc resection of lesion + rim
of haemosiderin-stained tissue
TWV
T
Hyalinised Thick Walled Vessels
[TWV] – Partly thrombosed [T]
• MK. 10 year old female
• 8 month hx of simple & complex partial seizures
secondary to right tempero-parietal lesion
• Failed multiple single & combination anti-convulsants
failed
– Side – effects
– Fatigue & Poor school performance
• Uneventful post-operative recovery.
• Seizure free in immediate post-operative
period.
• SC. 20 year old woman
• 18 yrs → two episodes of new onset seizures
• Imaging demonstrated left frontal 2cm x 2 cm lesion, ??
arterio-venous malformation
• Carbamazepine initiated.
• Cerebral angiography normal
Stealth-guided left frontal craniotomy and excision of lesion
Lumen
Hemosiderin
VWR
Vessel Wall Remnants [VWR]
Elastic
Vessel Wall Remnants
Siderocalcinosis – perilesional
Vascular Malformation remnants – Angio Negative – probable Cavernoma
• SC. 20 year old woman
• 18 yrs → two episodes of new onset seizures
• Imaging demonstrated left frontal 2cm x 2 cm lesion, ??
arterio-venous malformation
• Carbamazepine initiated.
• Cerebral angiography normal
• Uncomplicated recovery and
discharged home on post-operative day
4
• Cavernomas may be multiple, ranging from 1-12
• Size range from 0.1cm - 9cm
• Risk of haemorrhage estimated to be 2.5%
annually [cumulative].
• Risk of new onset seizures is 1.51% annually
[cumulative]
Most are sporadic.
Risk factors include:
• previous radiotherapy to brain
• more than one first degree relative with
cavernoma.
• 70% of patients with familial cavernomas carry a
frameshift mutation for either KRIT1 / CCM1,
MGC4607 / CCM2, or PDCD10 / CCM3,
mapping, respectively to chromosomes 7q, 7p,
and 3q.
•
•
•
•
0.5% of the population
~ 25% diagnosed before age 17
~ 63 - 81% supratentorial
Female preponderance; reason uncertain
May present with symptoms secondary
to haemorrhage:
• new onset seizures
• Hydrocephalus [superficial haemosiderosis]
• neurological deficit
also “Incidentaloma !!!”
MRI appearance:
• “mulberry” nodules with mixed
signal intensity
• peripheral haemosiderin rim is
seen as an area of decreased
signal intensity on T2-weighting
and as an area of mixed signal
intensity on T1-weighting
• no visible feeding vessels,
surrounding oedema, or mass
effect.
Angiographically occult
• Dilated sinuses [DS]
• Thin vessel walls [TWV] usually lack
smooth muscle, elastin, and
intervening parenchyma
• Electron-microscopy endothelial
cells → poorly developed tight
junctions, allowing for microhaemorrhages → characteristic
haemosiderin staining.
• Haemosiderin rim surrounded by
reactive gliosis.
• Thrombosis [T] may be present
DS
T
TWV
1. Reduces need for long-term anticonvulsants
2. Attainment of intellectual and learning
objectives
3. Avoid “labelling” of child as “epileptic”
4. ↓ long-term risk of haemorrhage
• Stealth-guided Craniotomies
• Excision not only of the cavernoma itself
(lesionectomy), but also excision of
haemosiderin ring, surrounding gliosis.
• In certain cases, may proceed to
hippocampectomy. (Varies centre to centre)
Seizure control appears to be better in patients who had excision of
haemosiderin ring. However, a clear correlation between extent of resection
and seizure control has yet to be established.
Post-operative seizure control is
dependent on: two factors:
1. Length of time the patient was
symptomatic pre-operatively. [The shorter
the duration of pre-operative seizures, the more likely it
is the patient will be seizure-free post-operatively].
2. ?? Extent of the surgical procedure
• Prognosis following surgical excision is usually
good
• Overall morbidity in most centres is around 4%.
• With complete excision of the lesion, the risk of
haemorrhage is non-existent.
• Cavernomas represent an uncommon but
treatable cause of epilepsy and cerebral
haemorrhage in the paediatric population.
• Symptomatic children diagnosed and
treated early will have a better postoperative result
References
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Labauge P, Brunereau L, Lévy C, Laberge S, Houtteville JP. The natural history of familial cerebral
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Raychaudhuri R, Batjer HH, Awad IA. Intracranial cavernous angioma: a practical review of clinical and
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Reson Imaging. 2006 Jun;24(5):631-7.
Chooi WK, Connolly DJ, Coley SC, Griffiths PD. Assessment of blood supply to intracranial pathologies in
children using MR digital subtraction angiography. Pediatr Radiol. 2006 Oct;36(10):1057-62. .
Pozzati E, Acciarri N, Tognetti F, Marliani F, Giangaspero F. Growth, subsequent bleeding, and de novo
appearance of cerebral cavernous angiomas. Neurosurgery. 1996 Apr;38(4):662-70.
Sürücü O, Sure U, Gaetzner S, Stahl S, Benes L, Bertalanffy H, Felbor U. Clinical impact of CCM mutation
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T
TWV
Hyalinised Thick Walled Vessels [TWV] – Partly thrombosed [T]
T
TWV
Hyalinised Thick Walled Vessels [TWV] – Partly thrombosed [T]