Tsukasa Nishiura

Prediction and evaluation of brainstem function by auditory brainstem responses in patients with uncal herniation

Serial measurements of auditory brainstem-evoked responses (BERs) were conducted in 15 patients with supratentorial mass lesions. Significant prolongation of the latency of wave V BERs, which originates in the inferior colliculus, occurred when the intracranial pressure (ICP) approached 30 mmHg. In four of five patients whose BERs were measured before pupillary changes, a significant lengthening of wave V latency was observed prior to clinical manifestation of uncal herniation. These results suggest that immediate medical or surgical decompression of ICP should be performed when ICP approaches 30 mmHg with significant prolongation of wave V latency.

Stenting for Internal Carotid Artery Stenosis Associated with Persistent Primitive Hypoglossal Artery Using Proximal Flow Blockade and Distal Protection System: A Technical Case Report and Literature Review

We report a very rare case of internal carotid artery (ICA) stenosis associated with persistent primitive hypoglossal artery (PPHA) treated by stenting using a proximal flow blockade and distal filter protection system. A 77-year-old man with a medical history of repeated cerebral infarction was referred to our hospital for treatment of progressive ICA stenosis. Cerebral angiography revealed that the degree of stenosis was 50% and the PPHA branched just distal to the stenosis at the C2 vertebral level. Black-blood magnetic resonance imaging indicated vulnerable plaque. The stenosis was at a high location, so carotid artery stenting was employed. Under the proximal flow blockade system with occlusion of the external and common carotid artery, distal filter protection was placed in the ICA to prevent distal embolization. A self-expanding stent was successfully deployed and the patient was discharged without any neurological deficits. In stenting for the ICA stenosis associated with PPHA, the combination of a proximal flow blockade and distal protection system is reasonable and safe.

Auditory Brain Stem Responses in Uncal Herniation

The authors have reported that in patients with uncal and central herniation, lengthening of the latency and deterioration of the wave form of the auditory brain stem response (BER) wave V, which originates in the inferior colliculus, correlated well with a rostrocaudal neurological impairment after pupillary change (Nagao et al. 1983). In this study, further investigations were carried out on whether or not the changes in BER wave V are related to the development of uncal herniation before pupillary changes and to obtain objective parameters, with which to assess the effectiveness of medical decompression of ICP in the stage of uncal herniation, manifested by pupillary change (Plum and Posner 1980).

Effects of methylprednisolone on cortical neural activity, blood flow, and water content in air exposure-induced cerebral edema

The correlation of changes in cortical neuron activity with water content and local cerebral blood flow was investigated in cats with brain edema produced by air exposure. The further effect of high-dose methylprednisolone on these factors was studied. Six hours after exposure of the brain surface to air, the water content of the white matter significantly increased. The local blood flow of the cortex and white matter significantly decreased with significant suppression of cortical neural activity (direct cortical response), indicating that ischemia was responsible for neural suppression. A single, large dose of methylprednisolone (30 mg/kg, i.v.) at the beginning of air exposure significantly reduced brain edema of the cortex and white matter 12 h after air exposure and improved the local blood flow of the cortex. Methylprednisolone also caused a remarkable improvement in cortical neural activity. This steroid effect on cortical neural function may play a role in the rapid neurologic improvement observed with their use in addition to the effect on brain edema.

Coronary Subclavian Steal Syndrome Successfully Treated with Subclavian Artery Stenting: A Report of 2 Cases

Coronary subclavian steal syndrome (CSSS) is a well-recognized phenomenon secondary to coronary artery bypass grafting and may cause myocardial ischemia. We report 2 cases of CSSS successfully treated with subclavian artery (SA) stenting. In both cases, an Optimo balloon guiding catheter was placed in the SA immediately proximal to the vertebral artery (VA) origin as a double protection system for the VA and left internal thoracic artery (LITA) graft. There were no periprocedural complications. Balloon protection for both the VA and LITA using a single balloon guiding catheter is a reasonable and safe technique for preventing distal embolisms.