WBR0343

Author	[[PageAuthor::Rim Halaby, M.D. [1]]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Pathophysiology
Sub Category	SubCategory::Neurology
Prompt	[[Prompt::A 64 year old man presents to the emergency department for acute onset headache, with severe nausea and vomiting. The patient reports that the pain woke him up from sleep and that he had vomited four times since the pain started. Shortly after arrival, the patient loses consciousness and attempts at arousal are unsuccessful. An emergent brain CT scan is shown below. Which of the following is the most important risk factor for this patient's condition? Image courtesy of Dr Frank Gaillard. Radiopaedia (original file here). Creative Commons BY-SA-NC]]
Answer A	AnswerA::Smoking
Answer A Explanation	AnswerAExp::Smoking is not associated with increased risk of Charcot-Bouchard microaneurysms. It increases the risk of ischemic strokes
Answer B	AnswerB::Hypertension
Answer B Explanation	AnswerBExp::Hypertension is the major risk factor for Charcot-Bouchard microaneurysms and intraparenchymal bleeds with 90% of patients presenting with high blood pressure.
Answer C	AnswerC::Diabetes mellitus
Answer C Explanation	AnswerCExp::Diabetes mellitus is not associated with increased risk of Charcot-Bouchard microaneurysms. It increases the risk of ischemic strokes.
Answer D	AnswerD::Marfan syndrome
Answer D Explanation	AnswerDExp::Marfan syndrome is associated with increased risk of berry aneurysms and subarachnoid hemorrhage not Charcot-Bouchard microaneurysms and intraparenchymal bleeds.
Answer E	AnswerE::Hypercholesterolemia
Answer E Explanation	AnswerEExp::Hypercholesterolemia is not associated with increased risk of Charcot-Bouchard microaneurysms. It increases the risk of ischemic strokes.
Right Answer	RightAnswer::B
Explanation	[[Explanation::Charcot-Bouchard microaneurysms are small dilatations in the brain vasculature characteristically located in vessels less than 300 mcm in diameter. These aneurysms are usually located in the deep brain structures in the particularly the basal ganglia, thalamus, and internal capsule. Charcot–Bouchard are stongly linked to chronic uncontrolled hypertension, and are a common cause of hemorrhagic strokes. The most common location is the putamen. Typical features include focal neurologic signs, headache, nausea, and altered levels of consciousness. Depending on extent of the bleed, CT scan usually shows a localized area of hyperdensity (appear bright) in the brain parenchyma typically resembling the image shown above. Educational objective: Charcot-Bouchard aneurysms are a major cause of hemorrhagic stroke associated with chronic hypertension. Reference: Strandgaard S, Paulson OB. Cerebrovascular consequences of hypertension. Lancet. 1994;344(8921):519-21. Educational Objective: References: ]]
Approved	Approved::No
Keyword	WBRKeyword::Charcot bouchard microaneurysms, WBRKeyword::Hypertension
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::