[A Case Of An Elderly Patient With Blake's Pouch Cyst].

Blake's pouch cyst is a congenital disease in which the ventricle enlargement is a non-communicating hydrocephalus. Some elderly patients have a process of the idiopathic normal pressure hydrocephalus (communicating hydrocephalus). We report an elderly patient with Blake's pouch cyst. A 68-year-old man visited our hospital with a gait disturbance that had begun 2 years previously but had become aggravated. He did not have dementia or urinary disturbance. CT scan and MRI showed the hydrocephalus included an IV ventricle, and the cerebrocerebellar fluid space in the posterior fossa was large. A Tap test was positive, so we attempted lumboperitoneal shunt, and his gait disturbance improved.

Primary central nervous system lymphoma of the third ventricle with intra-tumoral hemorrhage: A case report and literature review.

Primary central nervous system lymphoma (PCNSL) is a rare brain tumor that most commonly arises in the cerebral white matter, basal ganglia, peri-ventricle or corpus callosum. Confinement of PCNSL to the third ventricle is extremely rare, and seldom presents with intratumoral hemorrhage (ITH). The present study described the case of a 75-year-old woman who presented with obstructive hydrocephalus due to third-ventricle PCNSL. On magnetic resonance imaging (MRI), the tumor presented ITH on T2*-weighted images and a highly elevated regional cerebral blood volume on dynamic susceptibility contrast-enhanced MRI (DSC-MRI). Due to the high elevation of the regional cerebral blood volume, high-grade glioma was suspected as a preoperative diagnosis. The patient underwent endoscopic tumor biopsy and third ventricle PCNSL was successfully diagnosed. The patient achieved good prognosis at an early stage after the start of treatment initiation. There are many differential considerations for a third-ventricle tumor, and DSC-MRI can help the differential diagnosis of these tumors. Furthermore, the presence of ITH can lead to the inaccurate estimation of regional cerebral blood volume values. Overall, silent or microhemorrhage in PCNSL may be underestimated, and clinicians should therefore carefully evaluate tumor vascularity by MRI.