Characteristic and Management of Symptomatic Septum Pellucidum Cyst in Extreme Elderly Patient: Case Report and Literature Review

Septum pellucidum cyst is rare and is defined as a fluid-filled space between the lateral ventricles; it has a width of 10 mm or more. In this case report, a surgical patient of symptomatic septum pellucidum cyst (SPC) in extreme age is described. To the best our knowledge, this is the first report of an extremely aged patient with symptomatic SPC that was successfully treated using a flexible neuroendoscope. An 85-year-old male complained of gradually worsening gait disturbance, dementia, and urinary incontinence without headache and was admitted to our hospital. MRI revealed a huge cyst between the lateral ventricles as well as ventricle dilatation with periventricular hyperintensity in T2-weighted image. The patient was diagnosed with symptomatic hydrocephalus with SPC and underwent neuroendoscopic fenestration of the cyst with the use of a flexible endoscope without cerebrospinal fluid shunt placement. Immediately after the surgery, the patient's gait disturbance and dementia were dramatically improved. In extremely aged patients, SPC tended to develop with idiopathic normal pressure hydrocephalus-like symptoms, including gait disturbance without increasing intracranial pressure, sensorimotor disturbances, and psychological disorders. Neuroendoscopic cyst fenestration with the use of a flexible scope for SPC is a less-invasive procedure and should be considered even for extreme elderly symptomatic patients.

Boron Neutron Capture Therapy for Malignant Brain Tumors

Boron neutron capture therapy (BNCT) is a biochemically targeted radiotherapy based on the nuclear capture and fission reactions that occur when non-radioactive boron-10, which is a constituent of natural elemental boron, is irradiated with low energy thermal neutrons to yield high linear energy transfer alpha particles and recoiling lithium-7 nuclei. Therefore, BNCT enables the application of a high dose of particle radiation selectively to tumor cells in which boron-10 compound has been accumulated. We applied BNCT using nuclear reactors for 167 cases of malignant brain tumors, including recurrent malignant gliomas, newly diagnosed malignant gliomas, and recurrent high-grade meningiomas from January 2002 to May 2014. Here, we review the principle and history of BNCT. In addition, we introduce fluoride-18-labeled boronophenylalanine positron emission tomography and the clinical results of BNCT for the above-mentioned malignant brain tumors. Finally, we discuss the recent development of accelerators producing epithermal neutron beams. This development could provide an alternative to the current use of specially modified nuclear reactors as a neutron source, and could allow BNCT to be performed in a hospital setting.