WBR0540

Jump to navigation Jump to search
 
Author [[PageAuthor::Yazan Daaboul, M.D. (Reviewed by Alison Leibowitz) (Reviewed by Serge Korjian)]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Pathology
Sub Category SubCategory::Neurology
Prompt [[Prompt::A 74-year-old man is brought to the emergency department with a headache, decreased level of consciousness, and an altered mental state. Upon further questioning, the patient reports that he sustained a head trauma 2 weeks prior to presentation. His medical history is significant for coronary artery disease, type 2 diabetes mellitus, hypertension, and hyperlipidemia. A cranial CT scan demonstrates the findings in the image below. Which of the following causes best characterizes the patient's symptoms?

]]

Answer A AnswerA::Rupture of an arterial branch of the maxillary artery
Answer A Explanation [[AnswerAExp::Epidural hematoma results from a rupture of the meningeal artery, a branch of the maxillary artery. It is often due to a traumatic injury to the temporal bone. Epidural hematoma is characterized by a "lucid interval", a time delay before clinical symptoms manifest.]]
Answer B AnswerB::Rupture of a bridging vein
Answer B Explanation AnswerBExp::Subdural hematoma is characterized by crescent-shaped hemoarrhage upon CT scan.
Answer C AnswerC::Rutpure of a berry aneurysm
Answer C Explanation [[AnswerCExp::Subarachnoid hemorrhage often results from a rupture of a berry aneurysm. Berry aneurysms are frequently associated with three pathologies: Marfan syndrome, Ehler-Danlos syndrome, and adult-dominant polycystic kidney disease (ADPKD). Clinically, patients with subarachnoid hemorrhage complain of a severe, sudden-onset headache.]]
Answer D AnswerD::Reversible ischemia caused by arterial vasoconstriction
Answer D Explanation [[AnswerDExp::Transient ischemic attack (TIA) is characterized by a reversible vasoconstrictive process, which may manifest as cerebral ischemia and symptoms of stroke that often self-resolve. Although TIA is a reversible condition, it is a serious disease because it often heralds a stroke.]]
Answer E AnswerE::Decrease in the rate of cerebrospinal fluid (CSF) absorption
Answer E Explanation AnswerEExp::Communicating hydrocephalus is characterized by a decrease in CSF absorption, causing a build-up of CSF within the ventricles, leading to an increased intracranial pressure (ICP) and papilledema.
Right Answer RightAnswer::B
Explanation [[Explanation::A subdural hematoma is characterized by the rupture of a bridging vein. Because the venous pressure system is a low-presure system as compared to the arterial system, the build-up of blood following subdural hematoma is slow and gradual increase in hematoma size develops over a prolonged period of time. On CT scan, subdural hematoma appears as a crescent-shaped hemorrhage that does not cross the falx cerebra but may cross the suture lines.

Educational Objective: Upon CT scan, subdural hematoma, resulting from a rupture of bridging veins, appears as a crescent-shaped hemorrhage that crosses the suture lines but is unable to cross the falx cerebri.
References: First Aid 2014 page 462]]

Approved Approved::Yes
Keyword WBRKeyword::subdural hematoma, WBRKeyword::subarachnoid hemorrhage, WBRKeyword::subarachnoid hemorrhage, WBRKeyword::epidural hematoma, WBRKeyword::bridging veins, WBRKeyword::communicating hydrocephalus, WBRKeyword::aneurysm, WBRKeyword::headache, WBRKeyword::trauma, WBRKeyword::CT scan, WBRKeyword::TIA, WBRKeyword::transient ischemic attack, WBRKeyword::neurology, WBRKeyword::head trauma, WBRKeyword::rupture
Linked Question Linked::
Order in Linked Questions LinkedOrder::