A Case of Moyamoya Disease With Spontaneous Regression of Posterior Choroidal Artery Aneurysm After Improvement in Obesity and Administration of an Antihypertensive Drug.

A 24-year-old obese female (height = 162 cm, weight = 84 kg, and BMI = 32.0) developed transient dysarthria and left hemiparesis, which was diagnosed as moyamoya disease (MMD) after imaging studies. Cerebral angiography and single photon emission computed tomography studies revealed that the above symptoms were caused by hemodynamic insufficiency in the bilateral hemispheres with right-sided predominance, and a right-sided superficial temporal artery-middle cerebral artery bypass was performed.

Subarachnoid Hemorrhage From Ruptured Aneurysms at the Internal Carotid Artery-Posterior Communicating Artery Bifurcation Not Detectable on Preoperative Imaging Studies.

Since subarachnoid hemorrhage (SAH) due to the re-rupture of cerebral aneurysms severely worsens the prognosis, an accurate initial diagnosis is essential. Computed tomography (CT) and magnetic resonance imaging (MRI) usually detect aneurysmal subarachnoid hemorrhage (aSAH). However, in rare cases, its identification on CT- and MRI scans is difficult, and a cerebrospinal fluid (CSF) examination is required.