Abstract
Case report: We report a right-handed, 52-year-old woman who presented with gradually progressive apathy and abulia. She had been diagnosed as having obesity, hyperlipidemia, and hypertension. She previously had a lively character but became apathetic and abulic. These neuropsychiatric symptoms gradually worsened over a week. Neuropsychiatric examination showed a mild depressive state, dysfunction of the left frontal lobe and mild cognitive dysfunction. Brain MRI showed infarction extending from the capsular genu to the corona radiata in the left hemisphere, corresponding to the territory of the medial lenticulostriate arteries (LSA). MRA showed no severe stenosis in the bilateral MCA and flow sensitive black blood MRA showed reduced number of LSA, leading to the diagnosis of branch atheromatous disease (BAD) in the left capsular genu. After admission, she received anti-thrombotic therapy, and then her symptoms gradually resolved.
Discussion: Capsular genu infarction seemed to have damaged the anterior or inferior thalamic peduncles, leading to the thalamo-cortical disconnection and neuropsychiatric symptoms. Although BAD is known to cause progressive sensorimotor symptoms, the present patient showed no apparent neurological deficits except progressive neuropsychiatric symptoms. To our knowledge, 39 cases of capsular genu infarctions have been reported to present with neuropsychiatric symptoms. However, almost all of the cases show other neurological deficits as well. Therefore, progressive psychiatric symptoms are rare but should be considered as the sole symptoms in BAD for its proper and prompt treatment.
