Q? Neuroradiology This would be best described as a Spetzler grade: 1 2 3 4 5 ©™

Neuroradiology A. The correct answer is D. This arteriovenous malformation has a nidus is 3-6cm long, is in eloquent brain and has deep venous drainage. Table 1. Spetzler-Martin Grading System for AVMs Size of AVM*6 Eloquence of adjacent brain† Pattern of venous drainage‡ Small (<3 cm) 1 Noneloquent Superficial only Medium (3-6 cm) 2 Eloquent Deep component Large (>6 cm) 3 … * Measure the largest diameter of the nidus of the lesion on angiography. † Eloquent areas include sensorimotor, language, visual, thalamus, hypothalamus, internal capsule, brain stem, cerebellar peduncles, and deep cerebellar nuclei. ‡ The lesion is considered superficial only if all drainage is via the cortical drainage system. ©™

Q. Neuroradiology Describe the MRI findings. What is your differential diagnosis? What is this patient’s most likely clinical presentation?. ©™

A. Neuroradiology Describe the MRI findings. Left basal ganglia mass non-enhancing, T1 isointense, T2 hyperintense, heterogeneous intensity on DWI, hypo ADC. There is perilesional ischemic change. There is midline shift from left to right without ventriculomegaly. What is your differential diagnosis? Intrathalamic hemorrhage Hemorrhagic tumor Hemorrhagic stroke Arteriovenous malformation What is this patient’s most likely clinical presentation? 60 y/o African American male with a history of hypertension, now with a new complaint of dysarthria, right sided weakness. ©™

Q. Neuroradiology Basal ganglia mass continued… What are etiologies? Describe the MRI appearance by stages. ©™

A. Neuroradiology What are etiologies? HTN, amyloid angiopathy, tumor, arteriovenous malformations, vasculitis, and coagulopathy. Describe the MRI appearance: Hyperacute-(few hours post event)- contains OxyHb, T1 isointense, T2 hyperintense. Acute- (1-2days)- contains DeoxyHb, T1 hypo/isointense, T2 hypointense. Subacute- (days-weeks)- contains MetHb, intracellular (3-14 days) T1 hyper, T2 hypo; and extracellular (>2 weeks) T1 and T2 are both hyperintense. Chronic- (months)- contains ferritin and hemosiderin, T1 iso, T2 hypointense. Nonparamagnetic heme is T1 hypo, T2 hyper Mnemonic: acute, subacute, chronic- T1- George Washington Bridge (gray, white, black), T2- Oreo cookie (black, white, black) ©™ Bradley WG Jr: MR appearance of hemorrhage in the brain. Radiology 1993 Oct; 189(1): 15-26

Q. Neuroradiology This is the head CT scan of the previous case. Describe the findings on this head CT. Describe the arterial pathophysiology of chronic hypertension. How does this increase the risk of hemorrhage? ©™

A. Neuroradiology Describe the findings on this head CT. Left basal ganglia hyperdense mass with midline shift from left to right. No ventriculomegaly. These findings suggest acute intraparenchymal hemorrhage. Describe the arterial pathophysiology of chronic hypertension. Serum proteins accumulate in the basement membrane and causes collagen deposition, hyalinization of the media, atrophy of the muscularis layer, vessel dilatation or stenosis, and commonly fatty macrophage accumulation (LIPOHYALINOSIS). How does this increase the risk of hemorrhage? Hemorrhage may be caused by rupturing of vessel dilatations (CHARCOT-BOUCHARD ANEURYSMS), or by occlusion and secondary rupture of small penetrating arteries (commonly lenticulostriate). ©™

Q? Neuroradiology In adults, what is the upper limit of normal prevertebral soft tissue swelling in the C4 region? A. 10mm B. 7mm C. 20mm D. 4mm E. 30mm Used with permission from Handbook of Neurosurgery and Neurology in Pediatrics; By Chaim B. Colen, MD, PhD. ©™

A. Neuroradiology To find the answer to this card and over 300 others, Click here ©™ Handbook of Neurosurgery and Neurology in Pediatrics; By Chaim B. Colen, MD, PhD.