The authors describe the clinical observation of a patient with a paraventricular tumor of the left frontal lobe and demonstrate the effectiveness of endoscopic biopsy of a volumetric mass of such localization through the lateral ventricle using intraoperative navigation. The disease manifested with convulsive seizures two years before the patient was admitted to the hospital. During this period of time, he was repeatedly examined. The dimensions of the volumetric formation remained unchanged. Based on the data obtained, it was not possible to accurately verify the type of tumor. Anticonvulsant therapy was ineffective. The patient underwent surgery - endoscopic partial removal of the tumor (biopsy) and opening of the tumor cyst through the left lateral ventricle using intraoperative navigation. Clinical improvement in the patient's condition was achieved. After the operation, the headaches and the seizures stopped. Описано клиническое наблюдение пациента с паравентрикулярной опухолью левой лобной доли и продемонстрирована эффективность эндоскопической биопсии объемного образования данной локализации через боковой желудочек с применением интраоперационной навигации. Заболевание манифестировало судорожными приступами за 2 года до поступления пациента в стационар. В течение этого периода времени неоднократно обследовался, размеры объемного образования оставались без изменений. На основании полученных данных точно верифицировать тип опухоли не представлялось возможным. Противоэпилептическая терапия была неэффективной. Больному проведено эндоскопическое частичное удаление опухоли (биопсия) и вскрытие кисты опухоли через левый боковой желудочек с применением интраоперационной навигации. Достигнуто клиническое улучшение в состоянии пациента. После операции перестали беспокоить головные боли, прекратились судорожные приступы.

T2-FLAIR mismatch sign is known as a highly specific imaging marker of IDH-mutant astrocytomas. This study was intended to clarify what the T2-FLAIR mismatch sign represents by pathological analysis of lower-grade gliomas rediagnosed in accordance with the WHO 2016 classification. We retrospectively analyzed the records of 64 patients diagnosed with WHO grade II and III diffuse gliomas between June 2009 and November 2018. T2-FLAIR mismatch sign was found in 10 (45%) out of 22 patients with IDH-mutant astrocytoma, 1 (5%) out of 20 with oligodendroglioma, and 1 (5%) out of 22 with IDH-wild-type astrocytoma. T2-FLAIR mismatch sign as a marker of IDH-mutant astrocytomas showed positive predictive value of 83%. Among 22 patients with IDH-mutant astrocytomas, microcystic change was found in eight, of which seven showed T2-FLAIR mismatch sign. Microcystic change was significantly associated with T2-FLAIR mismatch sign (P < 0.01). From multi-sampling in a patient, abundant microcysts were observed upon HE staining of specimens from the T2-FLAIR mismatched region, while microcysts were hardly observed from the T2-FLAIR matched one. All three protoplasmic astrocytomas among our IDH-mutant astrocytomas presented T2-FLAIR mismatch sign. In conclusion, T2-FLAIR mismatch sign may reflect microcyst formation in IDH-mutant astrocytomas and be common in IDH-mutant protoplasmic astrocytoma.

It is presented case report of extremely rare pathology - protoplasmic astrocytoma of sylvian aqueduct involving posterior section of the third ventricle. The main principles of treatment were considered. Dynamics of neurological status was demonstrated. An effectiveness of treatment strategy was assessed. Представлен случай хирургического лечения и отдаленного наблюдения пациента с крайне редкой патологией - протоплазматической астроцитомы сильвиева водопровода с распространением на задний отдел III желудочка. Рассмотрены основные принципы лечения. Продемонстрирована динамика неврологического статуса. Сделано заключение об эффективности выбранной стратегии лечения.

Astrocytoma as one of the most common central nervous system (CNS) tumors is rarely reported in veterinary literature. A 7-year-old Persian Lori-Bakhtiari ewe was presented to the clinic with a two months history of progressive blindness, nystagmus to the right, bilaterally decreased pupillary reflexes, head pressing and paddling. At necropsy, a whitish well-circumscribed mass with dimensions of 3.50×2.50×1.50 cm was observed in the dorsal parietal lobe of the left cerebral hemisphere. Microscopically, the mass was well-circumscribed and highly cellular, consisted of round to elongated cells with scant and vacuolated cytoplasm with few, flaccid processes. The nuclei were round to oval with densely stippled chromatin and indistinct nucleoli. Immunohistochemical analyses showed positive staining for vimentin, S100 and glial fibrillary acidic protein. Definitive diagnosis of cerebral protoplasmic astrocytoma was made on the basis of the histopathological and immunohistochemical findings. This type of neoplasm should be included in the differential diagnosis of CNS lesions in the sheep.

Protoplasmic astrocytomas are a poorly characterized and extremely rare subtype of astrocytoma. We describe the CT, MR and 18F-fludeoxyglucose positron emission tomography (FDG-PET) findings of a multifocal protoplasmic astrocytoma in a 29-year-old male with neurological deficits. He was initially diagnosed with neurosarcoidosis based on imaging. MRI demonstrated intraparenchymal lesions involving the right temporal lobe and cerebellum. These appeared as extremely hyperintense signals on T 2 weighted imaging and as homogeneous enhancements with a small non-enhancing cystic component on contrast-enhanced MR. Diffuse post-contrast enhancement of the craniospinal meninges was also noted. Post-radiation therapy PET-CT demonstrated a highly FDG-avid tumour in the right temporal lobe and left cerebellum. To our knowledge, a multifocal form of protoplasmic astrocytoma in an adult patient has not been previously described.