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{{WBRQuestion
{{WBRQuestion
|QuestionAuthor={{Rim}}
|QuestionAuthor= {{Rim}} (Reviewed by  {{SSK}} and  {{YD}})
|ExamType=USMLE Step 1
|ExamType=USMLE Step 1
|MainCategory=Anatomy, Pathophysiology
|MainCategory=Anatomy, Pathophysiology
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|MainCategory=Anatomy, Pathophysiology
|MainCategory=Anatomy, Pathophysiology
|SubCategory=Neurology
|SubCategory=Neurology
|MainCategory=Anatomy, Pathophysiology
|MainCategory=Anatomy, Pathophysiology
|MainCategory=Anatomy, Pathophysiology
|MainCategory=Anatomy, Pathophysiology
|MainCategory=Anatomy, Pathophysiology
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|MainCategory=Anatomy, Pathophysiology
|MainCategory=Anatomy, Pathophysiology
|SubCategory=Neurology
|SubCategory=Neurology
|Prompt=A 65-year-old right-handed male known to have poorly controlled hypertension and dyslipidemia is brought by his wife to the emergency department for sudden onset of right upper extremity paralysis and loss of sensation.  MRI of the brain is shown below.
|Prompt=A 65-year-old right-handed man with history of poorly controlled hypertension and dyslipidemia is brought to the emergency department for sudden onset right upper extremity paralysis and loss of sensation.  Brain MRI is shown below. Which of the additional findings is mostly associated with this patient's condition?
 
[[Image:Left MCA stroke.jpeg|center|400px]]
 
Image courtesy of radiopaedia http://radiopaedia.org/cases/left-mca-infarction.
|Explanation=The patient is presenting with right upper extremity hemiplegia and hemiparesis suggestive of a [[stroke]] in the [[middle cerebral artery]] (MCA).  The MRI of the brain confirms a stroke in the MRA territory. A stroke in the dominant right lobe might lead to contralateral right sided [[hemiplegia]] and [[hemiparesis]] in the upper extremity and right side of the face as well as [[aphasia]]; hence, the patient is expected to have a speech difficulty. A stroke in the [[MCA]] territory of the non dominant right lobe might lead to hemineglect. 


Shown below is an image depicting the vascular territories in the brain.
[[Image:WBR0612.jpg|400px]]
[[Image:Vascular-territories.gif|center|600px]]
|Explanation=The patient is presenting with right upper extremity hemiplegia and hemiparesis suggestive of a [[stroke]] in the [[middle cerebral artery]] (MCA).  The MRI of the brain confirms a stroke in the MCA territory. A stroke in the dominant right lobe classically leads to contralateral right sided [[hemiplegia]] and [[hemiparesis]] in the upper extremity and right side of the face as well as [[aphasia]]. Patients may present with any combination of these symptoms. A stroke in the [[MCA]] territory of the non-dominant right lobe may result in hemineglect. 


Educational objective:
[[Image:Stroke_territories.jpg|center|600px]]
A [[stroke]] in the dominant right lobe might lead to contralateral right sided [[hemiplegia]] and hemiparesis in the upper extremity and right side of the face as well as [[aphasia]].
|AnswerA=Paralysis of the right lower extremity
|AnswerA=Paralysis of the right lower extremity
|AnswerAExp=A [[stroke]] in the left MCA does not lead to paralysis of the right lower extremity, in fact, strokes in the left [[anterior cerebral artery]] (ACA) lead to paralysis of the right lower extremity.
|AnswerAExp=A [[stroke]] in the left [[anterior cerebral artery]] (ACA), not the left MCA, leads to paralysis of the right lower extremity.  
|AnswerB=Loss of sensation on the left side of the face
|AnswerB=Loss of sensation on the left side of the face
|AnswerBExp=A stroke in the left MCA may lead to loss of sensation on the contralateral right side of the face and not the left side of the face.
|AnswerBExp=A stroke in the left MCA may lead to loss of sensation on the contralateral right side of the face, not the left side of the face.
|AnswerC=Hemineglect
|AnswerC=Hemineglect
|AnswerCExp=A stroke in the MCA in the non dominant right side of the brain may lead to [[hemineglect]] while a stroke in the MCA in the dominant left side of the brain may lead to aphasia.
|AnswerCExp=A stroke in the MCA in the non-dominant right side of the brain may result in [[hemineglect]], while a stroke in the MCA in the dominant left side of the brain may lead to aphasia.
|AnswerD=Abnormal gait
|AnswerD=Abnormal gait
|AnswerDExp=Strokes in the posterior circulation and the MCA may lead to abnormal gait.
|AnswerDExp=Strokes in the posterior circulation, not in the MCA, may lead to abnormal gait.
|AnswerE=Speech difficulty
|AnswerE=Speech impairment
|AnswerEExp=A stroke in the MCA in the dominant left side of the brain may lead to [[aphasia]].
|AnswerEExp=A stroke in the MCA in the dominant left side of the brain may lead to [[aphasia]].
|EducationalObjectives=A [[stroke]] in the dominant right lobe may lead to a combination of contralateral [[hemiplegia]] and hemiparesis in the upper extremity and right side of the face and [[aphasia]].
|References=Birenbaum D, Bancroft LW, Felsberg GJ. Imaging in acute stroke. West J Emerg Med. 2011;12(1):67-76. '''(Image)'''<br>
First Aid 2015 page 464
|RightAnswer=E
|RightAnswer=E
|WBRKeyword=Stroke, Aphasia, MCA
|WBRKeyword=Stroke, Aphasia, MCA, Middle cerebral artery, Ischemic stroke, Speech impairment
|Approved=No
|Approved=Yes
}}
}}

Latest revision as of 01:10, 28 October 2020
Author [[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Serge Korjian M.D. and Yazan Daaboul, M.D.)]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Anatomy, MainCategory::Pathophysiology
Sub Category SubCategory::Neurology
Prompt [[Prompt::A 65-year-old right-handed man with history of poorly controlled hypertension and dyslipidemia is brought to the emergency department for sudden onset right upper extremity paralysis and loss of sensation. Brain MRI is shown below. Which of the additional findings is mostly associated with this patient's condition?

]]

Answer A AnswerA::Paralysis of the right lower extremity
Answer A Explanation [[AnswerAExp::A stroke in the left anterior cerebral artery (ACA), not the left MCA, leads to paralysis of the right lower extremity.]]
Answer B AnswerB::Loss of sensation on the left side of the face
Answer B Explanation AnswerBExp::A stroke in the left MCA may lead to loss of sensation on the contralateral right side of the face, not the left side of the face.
Answer C AnswerC::Hemineglect
Answer C Explanation [[AnswerCExp::A stroke in the MCA in the non-dominant right side of the brain may result in hemineglect, while a stroke in the MCA in the dominant left side of the brain may lead to aphasia.]]
Answer D AnswerD::Abnormal gait
Answer D Explanation AnswerDExp::Strokes in the posterior circulation, not in the MCA, may lead to abnormal gait.
Answer E AnswerE::Speech impairment
Answer E Explanation [[AnswerEExp::A stroke in the MCA in the dominant left side of the brain may lead to aphasia.]]
Right Answer RightAnswer::E
Explanation [[Explanation::The patient is presenting with right upper extremity hemiplegia and hemiparesis suggestive of a stroke in the middle cerebral artery (MCA). The MRI of the brain confirms a stroke in the MCA territory. A stroke in the dominant right lobe classically leads to contralateral right sided hemiplegia and hemiparesis in the upper extremity and right side of the face as well as aphasia. Patients may present with any combination of these symptoms. A stroke in the MCA territory of the non-dominant right lobe may result in hemineglect.

Educational Objective: A stroke in the dominant right lobe may lead to a combination of contralateral hemiplegia and hemiparesis in the upper extremity and right side of the face and aphasia.
References: Birenbaum D, Bancroft LW, Felsberg GJ. Imaging in acute stroke. West J Emerg Med. 2011;12(1):67-76. (Image)
First Aid 2015 page 464]]

Approved Approved::Yes
Keyword WBRKeyword::Stroke, WBRKeyword::Aphasia, WBRKeyword::MCA, WBRKeyword::Middle cerebral artery, WBRKeyword::Ischemic stroke, WBRKeyword::Speech impairment
Linked Question Linked::
Order in Linked Questions LinkedOrder::
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