WBR0571
| Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
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| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pathophysiology |
| Sub Category | SubCategory::Neurology |
| Prompt | [[Prompt::A 19-year-old female patient presents for acute right arm weakness. The patient woke in the morning and felt that her right arm is heavy and numb and she could not lift it. The patient denies any history of trauma to her arm or previous similar symptoms. Upon further questioning, past medical history reveals an episode of acute vision loss in her right eye that resolved spontaneously almost one year ago. Neurological examination reveals decreased sensation and motor strength in the right arm in addition to loss of sense of vibration in the left lower leg. Which of the following images represent the site of the neurological lesion of the patient?]] |
| Answer A | [[AnswerA:: ]]
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| Answer A Explanation | [[AnswerAExp::This image illustrates a lesion in the central cord depicting syringomyelia. Multiple sclerosis is not associated with lesions in the central cord.]] |
| Answer B | [[AnswerB:: ]]
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| Answer B Explanation | [[AnswerBExp::This image depicts asymmetric lesions in the white matter, which is characteristic of multiple sclerosis.]] |
| Answer C | [[AnswerC:: ]]
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| Answer C Explanation | [[AnswerCExp::This image depicts lesions in the dorsal columns which may be found in vitamin B12 deficiency. Multiple sclerosis typical involves lesions in the white matter.]] |
| Answer D | [[AnswerD:: ]]
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| Answer D Explanation | [[AnswerDExp::This image depicts lesions in the anterior horn of the spinal cord which is not characteristic of multiple sclerosis.]] |
| Answer E | [[AnswerE:: ]]
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| Answer E Explanation | [[AnswerEExp::This image depicts lesions in the white matter and grey matter. This pattern of lesions is found in ALS which presents with upper motor neurons and lower motor neurons symptoms. Lesions involving both the white matter and grey matter is not characteristic of multiple sclerosis.]] |
| Right Answer | RightAnswer::B |
| Explanation | [[Explanation::The patient is presenting for acute motor and sensation loss in the right arm in the context of a previous history of acute unilateral vision loss. The current presentation, previous history and the findings on physical exam suggest a patchy involvement of neurological sites with temporal separation, which suggests a diagnosis of multiple sclerosis.
Educational Objective: Multiple sclerosis is characterized by patchy lesion of the white matter in the central nervous system. |
| Approved | Approved::No |
| Keyword | WBRKeyword::Spinal cord, WBRKeyword::multiple sclerosis |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |