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Multiple
Choice
Questions
Section
The Neurosciences Journal includes this section of multiple choice questions as
part of its commitment to continuous education and learning in Neurosciences.
Experts in various neuroscience specialties are invited to participate with their
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Neurology, neurosurgery, and other board residents are encouraged to read
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Posterior fossa arteriovenous malformations
Hosam M. Al-Jehani, MBBS, FRCSC.
From the Department of Neurology and Neurosurgery, Montreal Neurological Institute/Hospital, McGill University, Montreal, Canada, and the
Department of Neurosurgery, King Fahad University Hospital, University of Dammam, Al-Khobar, Kingdom of Saudi Arabia.
E-mail: hosam.aljehani@gmail.com
Choose the most appropriate single answer.
1. Which of the following arteriovenous malformation (AVM) classification systems is best suited for posterior fossa
AVMs.
a. Spetzler-Martin
b. Samson
c. McCormick
d. Shi and Chen
2. Posterior fossa AVMs can present with ALL of the following except:
a. Cranial nerve palsies
b. Hydrocephalus
c. Hemorrhage
d. Seizures
3. According to the most applicable classification system of posterior fossa AVMs, the following are part of the
classification except:
a. Cerebellar hemispheres
b. Tonsillar
c. Brainstem
d. Vermian
e. Supranterially combined AVMs
4. Each of the following classes of posterior fossa AVMs receives unilateral blood supply except:
a. Hemispheric
b. Brainstem
c. Vermian
d. Tonsillar
5. In terms of treatment options, which of the following statements is true:
a. Endovascular embolization is the treatment of choice for brainstem AVMs
b. Radiosurgery is more effective in older patients
c. Pre-operative endovascular embolization does not alter the surgical morbidity in posterior fossa AVMs
d. The plane of dissection is more indistinct than supratentorial AVMs
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Posterior fossa AVMs
Answers:
1. b
Spetzler-Martin classification is the classical system to classify AVMs, but it has not been well validated for posterior
fossa AVMs. Shi and Chen is a complex system for AVM classification that is not specific to P-fossa AVMs. McCormick
classification is for all cerebral vascular malformation (AVMs, cavernous angioma, capillary telangiectasia, venous
angiomas).1
2. d
There has been no link between posterior fossa AVMs and seizures.2
3. e
True combined supratentorial and infrantorial AVM nidus is not possible because of the embryological origin of each
compartment. Nonetheless, it is important to note the venous drainage of the posterior fossa AVMs can be supratentorial
to the Galenic system, especially in the vermian type of AVMs.3
4. c
This has the surgical implication of the need for a midline exposure for such AVMs and the rest can be approached via
a lateral trajectory approach.3
5. d
The plane of dissection in not indistinct from the parenchyma, a point that might complicate the excision of the AVM,
especially when encountering a brainstem AVM.3
References
1.Quinones-Hinojosa A. Schmidek and Sweet Operative Neurosurgical Techniques: Indications, Methods and Results. 6th ed.
Philadelphia (PA): Saunders; 2012.
2.Hoh BL, Chapman PH, Loeffler JS, Carter BS, Ogilvy CS. Results of multimodality treatment for 141 patients with brain
arteriovenous malformations and seizures: factors associated with seizure incidence and seizure outcomes. Neurosurgery 2002;
51: 303-311.
3.Winn RH. Youmans Neurological Surgery. 6th ed. Philadelphia (PA): Saunders; 2011.
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