[Apperceptive and associative visual object agnosia in patients with acute ischemic stroke]. / Appertseptivnaya i assotsiativnaya zritel'naya ob"ektnaya agnoziya v ostrom periode ishemicheskogo insul'ta.

Visual object agnosia (VOA) is a loss of the ability to recognize visible objects in patients with the intact primary visual functions and in the absence of dementia. The apperceptive and associative variants of VOA are marked out. The apperceptive VOA is thought to be due to «pre-semantic¼ impairment of visual information processing. The associative VOA is caused by the loss of access to knowledge about the objects, and its semantic subtype is due to the disintegration of this knowledge itself. It is important to diagnose VOA and its variants in time to provide individualized approaches to medical rehabilitation of patients. Case reports of apperceptive and associative VOA in acute ischemic stroke are presented in this paper. These case reports indicate the possibility of the development of apperceptive and associative VOA in unilateral acute ischemic brain lesion. The variants of VOA can be recognized only by a detailed neuropsychological examination.

Prognostic Value of Investigating Neuron-Specific Enolase in Patients with Ischemic Stroke.

The aim of the study was to assess the prognostic value of the plasma neuron-specific enolase (NSE) level as a predictor of functional outcome and motor function recovery in the acute period of ischemic stroke (IS). Materials and Methods: Fifty patients with IS have been examined. On admission to the hospital and at 12-14 days after stroke onset, a clinical and neurological examination have been carried out with the supplementary quantitative assessment of neurological deficit severity according to the National Institutes of Health Stroke Scale (NIHSS), functional outcome according to the Modified Rankin Scale, and Rivermead Mobility Index. Enzyme immunoassay was used to determine NSE concentration in blood plasma in the acute period of the disease. Results: The NSE level in patients' blood plasma in the first 48 h after stroke onset positively correlates with the ischemic focus volume (r=0.49; p=0.003) and the severity of neurological symptoms (according to NIHSS) (r=0.33; p=0.02). NSE less than 2 ng/ml in the acute disease period is a predictor of good functional outcome 12-14 days after stroke onset (OR=12.4; р=0.006). The NSE level >2.6 ng/ml is associated with a high likelihood of lethal outcome.Neurological deficit below 15 according to NIHSS as well as the NSE level <2 ng/ml in the acute IS period are estimated as prognostic factors of significant recovery of motor function at 2 weeks after disease onset (OR=5.8; р=0.02). Conclusion: Determination of NSE in blood plasma makes it possible to predict functional outcome of the disease development and the recovery of motor function in patients with IS.

[Cerebral amyloid angiopathy, comorbid atrial fibrillation]. / Tserebral'naya amiloidnaya angiopatiya, komorbidnaya s fibrillyatsiei predserdii.

Cerebral amyloid angiopathy (CAA) is caused by the deposition of ß-amyloid in small vessels in the cerebral cortex and leptomeninges. Nowadays, CAA is recognized more often due to the development of neuroimaging technologies. The frequency of CAA increases in old age that explains its frequent association with cardiovascular diseases. Combination of CAA with atrial fibrillation (AF) causes particular difficulties in managing of the patients, since antithrombotic drugs prescribed to patients with AF mostly contraindicated in CAA because of increased risk of intracerebral hemorrhages. The article presents a case report of the patient with AF who was admitted to the stroke center with acute ischemic stroke. According to MRI, the focus of acute ischemia was small and localized in the cerebellum. This stroke was regarded as having an undetermined etiology according TOAST classification. Small-vessel occlusion subtype was not diagnosed because the TOAST criteria do not attribute an ischemic focus in the cerebellum to a lacunar stroke, while cardioembolic subtype was rejected due to a small (less than 1.5 cm in diameter) size of the focus. Probable CAA in the patient was diagnosed on the basis of the following MRI data: multiple cortical-subcortical micro-hemorrhages (T2*GRE); a single cortical focus with features of the hemorrhage at the stage of intracellular methemoglobin deposition (T1- weighted MR images); bilateral enlargement of perivascular spaces in semioval centers (FLAIR); a negative fronto-occipital gradient (T2-weighted MR images). A diagnosis of CAA was made in accordance with the 2010 Boston criteria and 2019 recommendations of the International CAA Association. The article discusses the hemorrhagic and non-hemorrhagic MRI features of CAA. Frequency of occurrence of cortical microinfarcts in CAA is discussed as well as their differences from small cardioembolic infarcts in AF. Algorithms for antithrombotic therapy for secondary prevention of ischemic stroke in patients with CAA and AF are considered.

[Topographical Disorientation in Patients with Brain Impairment]. / Topograficheskaia dezorientatsiia u bol'nykh s porazheniem golovnogo mozga.

The paper describes symptoms, pathogenesis and variants of topographic disorientation. The restorative and compensatory rehabilitation strategies in topographical disorientation are reviewed. It has been concluded that clarification of the variant of topographic disorientation and selection of optimal neurorehabilitation strategies is of great importance for improving medical and social outcomes in patients with stroke and other focal brain lesions.

[Topographical disorientation in patients with brain impairment]. / Topograficheskaia dezorientatsiia u bol'nykh s porazheniem golovnogo mozga.

Topographical disorientation refers to inability to recognize the environment, as well as to orient, to find the right way into a familiar or new environment and to use a map for the orientation. These functions are based on neuronal activity of posterior parietal cortex, retrosplenial cortex and the posterior part of cingular gyrus, medial temporal lobe, lingual gyrus and prefrontal cortex and are considered within egocentric or allocentric (exocentric) reference systems. Object locations in the egocentric system are evaluated with respect to the subject's body position while object locations in the allocentric reference frame are evaluated with respect to the object-to-object relations in the external environment. Topographical orientation disorders are observed in local lesions of the brain and in neurodegenerative diseases. The topographical disorientation may be due to landmark аgnosia, egocentric disorientation, heading disorientation and anterograde disorientation. Clinical tests for the diagnosis of topographical disorientation include blanket methods and navigation tasks in real or virtual space. The restorative and compensatory strategies are used in rehabilitation of patients with topographical disorientation. Clarification of the general strategy and selection of the optimal neurorehabilitation methods depend on the causes and severity of brain lesions.