WBR0343

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Author [[PageAuthor::Serge Korjian M.D. (Reviewed by Alison Leibowitz) (Reviewed by Serge Korjian)]]
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 with acute onset headache, severe nausea, and vomiting. The patient reports that the pain woke him up and he has vomited four times since the pain began. Shortly after arrival, the patient loses consciousness and attempts at arousal are unsuccessful. An emergent brain CT scan is illustrated 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 an increased risk of Charcot-Bouchard aneurysms, but may increase the risk of ischemic strokes.]]
Answer B AnswerB::Hypertension
Answer B Explanation [[AnswerBExp::Hypertension is the major risk factor for Charcot-Bouchard aneurysms 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 an increased risk of Charcot-Bouchard aneurysms, but may increase the risk of ischemic strokes.]]
Answer D AnswerD::Marfan syndrome
Answer D Explanation [[AnswerDExp::Marfan syndrome is associated with an increased risk of berry aneurysms and subarachnoid hemorrhage, but not Charcot-Bouchard aneurysms nor intraparenchymal bleeds.]]
Answer E AnswerE::Hypercholesterolemia
Answer E Explanation [[AnswerEExp::Hypercholesterolemia is not associated with an increased risk of Charcot-Bouchard aneurysms, but may increase the risk of ischemic strokes..]]
Right Answer RightAnswer::B
Explanation [[Explanation::Charcot-Bouchard aneurysms, small dilatations in the brain vasculature, are 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 aneurysms are linked to chronic uncontrolled hypertension, and are a common cause of hemorrhagic strokes, frequently originating in the basal ganglia, thalamus, pons, or subcortical white matter. Typical manifestations include focal neurological signs, headache, nausea, and altered levels of consciousness. Depending on extent of the hemorrhage, CT scans usually display a localized area of hyperdensity (which appear bright) in the brain parenchyma, typically resembling the image above.

Educational Objective: Charcot-Bouchard aneurysms, a major cause of hemorrhagic stroke, are associated with chronic hypertension.
References: Strandgaard S, Paulson OB. Cerebrovascular consequences of hypertension. Lancet. 1994;344(8921):519-21.]]

Approved Approved::Yes
Keyword WBRKeyword::Charcot-Bouchard aneurysms, WBRKeyword::Hypertension, WBRKeyword::aneurysm, WBRKeyword::brain, WBRKeyword::hemorrhagic stroke, WBRKeyword::chronic
Linked Question Linked::
Order in Linked Questions LinkedOrder::