Memory impairment caused by cerebral hematoma in the left medial temporal lobe due to ruptured posterior cerebral artery aneurysm

BACKGROUND: Cognitive disorders, such as memory disturbances, are often observed following a subarachnoid hemorrhage. We present a very rare case where rupture of a posterior cerebral artery aneurysm caused restricted damage to the hippocampus unilaterally, and caused memory disturbances. CASE PRESENTATION: A 56-year-old, right-handed man, with a formal education history of 16 years and company employees was admitted to our hospital because of a consciousness disturbance. He was diagnosed as having a subarachnoid hemorrhage due to a left posterior cerebral artery dissecting aneurysm, and coil embolization was performed. Subsequently, he had neither motor paresis nor sensory disturbances, but he showed disorientation, and both retrograde and anterograde amnesia. Although immediate recall and remote memory were almost intact, his recent memory was moderately impaired. Both verbal and non-verbal memories were impaired. Brain computed tomography (CT) and magnetic resonance imaging (MRI) revealed a cerebral hematoma in the left temporal lobe involving the hippocampus and parahippocampal gyrus, and single-photon emission computed tomography (SPECT) demonstrated low perfusion areas in the left medial temporal lobe. CONCLUSIONS: We suggest that the memory impairment was caused by local tissue destruction of Papez’s circuit in the dominant hemisphere due to the cerebral hematoma

Development of a high-resolution two-dimensional detector-based dose verification system for tumor-tracking irradiation in the CyberKnife system

We aim to evaluate the basic characteristics of SRS MapCHECK (SRSMC) for CyberKnife (CK) and establish a dose verification system using SRSMC for the tumor-tracking irradiation for CK. The field size and angular dependence of SRSMC were evaluated for basic characterization. The output factors (OPFs) and absolute doses measured by SRSMC were compared with those measured using microDiamond and microchamber detectors and those calculated by the treatment planning system (TPS). The angular dependence was evaluated by comparing the SRSMC with a microchamber. The tumor-tracking dose verification system consists of SRSMC and a moving platform. The doses measured using SRSMC were compared with the doses measured using a microchamber and radiochromic film. The OPFs and absolute doses of SRSMC were within ±3.0% error for almost all field sizes, and the angular dependence was within ±2.0% for all incidence angles. The absolute dose errors between SRSMC and TPS tended to increase when the field size was smaller than 10 mm. The absolute doses of the tumor-tracking irradiation measured using SRSMC and those measured using a microchamber agreed within 1.0%, and the gamma pass rates of SRSMC in comparison with those of the radiochromic film were greater than 95%. The basic characteristics of SRSMC for CK presented acceptable results for clinical use. The results of the tumor-tracking dose verification system realized using SRSMC were equivalent to those of conventional methods, and this system is expected to contribute toward improving the efficiency of quality control in many facilities

Analysis of restenosis after carotid artery stenting : preliminary results using computational fluid dynamics based on three-dimensional angiography

Currently carotid artery stenting (CAS) is a widely used technique for the treatment of carotid artery stenosis. However, some patients with restenosis following CAS have been reported, resulting in potential clinical problems. The purpose of this study was to investigate the hemodynamic changes before and after CAS to find the factors that may influence restenosis. Five patients (two with restenosis, three without restenosis) were included in this study. The geometry and rheological conditions of the carotid arteries were obtained from three-dimensional digital subtraction angiography and ultrasound measurements. Computational fluid dynamics (CFD) modelling was performed to calculate wall shear stress (WSS), wall shear stress gradient (WSSG) and internal carotid artery (ICA) flow ratio. In addition, morphologic analysis was carried out. CFD results indicated that the WSSG of the restenosis group was significantly larger than that of the no-restenosis group. In the restenosis group, the WSS distribution after CAS showed a significant variation at the ICA. The average ICA flow ratio of the restenosis group was 43.5%, while in the no-restenosis group it was 68.6%. Furthermore, there were similar significant differences between the two groups during morphology analysis. CFD technology is useful for physicians in estimating haemodynamic changes during ICA stenosis treatment. These parameters, including ICA flow ratio and WSS distribution, may help to predict carotid restenosis. In future, CFD combined with other medical techniques such as digital subtraction angiography, MRI and pathology technologies will be available for the clinical estimation of ICA restenosis.6 page(s

Agraphia Caused by Left Thalamic Hemorrhage

A 71-year-old right-handed man was admitted to our hospital with right hemiparesis and sensory impairment associated with mild aphasia. Although aphasia gradually resolved within 2 weeks after stroke onset, his writing ability remained disturbed. A computed tomography (CT) scan at stroke onset revealed a hematoma in the left thalamus, but no cortical lesions were observed. Further, a single-photon emission CT (SPECT) scan showed decreased blood flow in the left thalamus, in the cortical region extending from the left superior temporal gyrus to the parietal lobe, and in the frontal lobe. It is possible that agraphia may have directly resulted from the thalamic lesion, but SPECT findings strongly suggested that a general decrease in left cortical function concomitant with a disruption of the thalamocortical and cortico-thalamocortical projection fibers produced these cognitive deficits

A Case of Curable Dementia Treated by Effective Endovascular Embolization for Dural Arteriovenous Fistula

Background: We report a case in which an effective endovascular treatment cured the worsening of dementia due to a dural arteriovenous fistula (dAVF). Case Report: A 73-year-old woman suffered for 1.5 years from gait disturbance and disorientation that were suspicious of dementia. A brain MRI revealed that her symptoms were likely due to dAVF. An angiography provided a definitive diagnosis of dural transverse-sigmoid sinus fistula. Transvenous embolization completely occluded the fistula and led to a significant improvement of her cognitive function in tandem with a restoration of the cerebral blood flow. Conclusion: Endovascular treatment for dAVF is sometimes effective in treating worsening dementia, which might be due to the drastic change in cerebral blood flow in the area relevant to the cognitive function

Unexpected Lethal Complication of Ventricular Fibrillation in Symptom Free Variant Angina Pectoris

We report an unexpected sudden cardiac death due to variant angina complicated by ventricular fibrillation occurring during routine ambulatory electrocardiographic monitoring. The patient had one previous episode of ventricular fibrillation before the lethal event. He had no significant coronary artery disease and was asymptomatic throughout his illness. In clinical practice, when an episode of ventricular fibrillation is noted, one should be aware of the risk of sudden cardiac death, even if the patient's vasospastic angina is relatively stable and asymptomatic