Hiroyuki Masaoka

Saccular Aneurysms of the Distal Anterior Cerebral Artery

We report a series of 42 consecutive patients with aneurysms of the distal anterior cerebral artery (ACA). Of these, 36 patients had one aneurysm, 5 had two aneurysms, and one had three aneurysms. Thirty patients had a ruptured distal ACA aneurysm; among these patients, the size of the aneurysm was less than 5 mm in diameter in 20, 6 to 10 mm in 7, and larger than 11 mm in 3. Eighteen patients (42.9%) had multiple aneurysms, and distal ACA aneurysms were responsible for a subarachnoid hemorrhage in 10. Thirty-four patients underwent direct surgery, and 30 of these had excellent outcomes 3 months after surgery. The treatment of patients with distal ACA aneurysms is often technically difficult, because of their broad neck configuration and the coexistence of other aneurysms. Nevertheless, the present study emphasizes that distal ACA aneurysms tend to bleed, irrespective of their size, and that excellent outcomes are obtainable by direct surgery.

Symptoms and their pattern of progression in childhood moyamoya disease

In the series of 81 childhood moyamoya patients, the common pattern of clinical progression seen in 77 patients was revealed to be no more than four. The characteristics of each type of clinical progression were presented for a better understanding of the disease and for an initiation of early treatment of this rather rare and insidiously progressive disease. Type I (21 cases) and type II (15 cases) are cases without infarction, even in those types there are cases with poor IQ. Type III (17 cases) and type IV (24 cases) are cases with infarction and an early operation is mandatory. Types I and II are also good candidates for early operation, for IQ deterioration insidiously progress in these types and there is no way of knowing them from type III before infarctions occur. We now have effective surgical measures to improve the ischemic conditions of this disease.

MENTAL OUTCOME FOLLOWING ENCEPHALODUROARTERIOSYNANGIOSIS IN CHILDREN WITH MOYAMOYA DISEASE WITH THE ONSET EARLIER THAN 5 YEARS OF AGE

The mental prognosis of children with moyamoya disease, in whom the onset was when they were younger than 5 years of age, has been reported to be very poor. We studied the mental outcome of these patients after encephaloduroarteriosynangiosis (EDAS) in relation to the age at the onset of the disease and the age at operation. For patients in whom the onset of moyamoya disease occurs when they are younger than 2 years of age, the prognosis is very poor with regard to mental abilities even if they have an operation within a year after the onset. Slight hope remains if the operation is within 3 months of the onset. For patients in whom the disease begins when they are 2–5 years of age, EDAS performed before the age of 9 years may result in a good outcome with regard to mental ability, as well as resolution of the paroxysmal symptoms and crebral revascularization.

Surgical Outcome following Decompressive Craniectomy for Poor-Grade Aneurysmal Subarachnoid Hemorrhage in Patients with Associated Massive Intracerebral or Sylvian Hematomas

Background: Patients with poor-grade aneurysmal subarachnoid hemorrhage (SAH) presenting with large intracerebral (ICH) or sylvian hematomas (SylH) have poor outcomes due to the mass effect of significant brain stem compression following mass effect. On the other hand, decompressive craniectomy (DC) can reduce morbidity and mortality in critically ill patients with massive ischemic infarction and severe head injury. However, the role of DC in SAH patients is not fully understood. We investigated the outcome of DC in poor-grade SAH presenting with large ICH or SylH. Methods: 110 consecutive patients with poor-grade SAH (Hunt & Kosnik (H&K) grades IV and V, and Fisher group 4) were admitted to our hospital between April 1, 1993, and July 30, 2004. We treated 57 of those who presented with large ICH or SylH using DC. We retrospectively reviewed medical charts, radiological findings, operative notes, and video records. Results: Among the 57 patients (mean age 57.8, male 29, female 28), 25 were classified as H&K grade IV and 32 as grade V. Ruptured aneurysms were located on the internal carotid artery in 11 and the middle cerebral artery in 46 patients. 50 of the aneurysms were small, 5 were medium, and 2 were large. Rerupture was preoperatively confirmed in 13 (22.8%). Hypothermia was applied to 17 (29.8%). The Glasgow Outcome Scale on discharge showed good recovery, moderate recovery, severe disability, vegetative state, and death in 8 (14.0%), 13 (22.8%), 16 (28.1%), 8 (14.0%), and 12 (21.1%), respectively. The outcomes of grade IV patients were favorable and poor in 14 (56.0%) and 10 (40.0%), respectively, and 1 (4.0%) died. Conclusion: Several experimental studies have also indicated that DC significantly improves outcome due to reduced intracranial pressure or increased perfusion pressure. Urgent DC for poor-grade SAH with space-occupying hematoma can lead to survival with good recovery in some patients.

Clinical and radiological findings and surgical management of ruptured aneurysms at the non-branching sites of the internal carotid artery

Ruptured aneurysms located at the non-branching sites of the internal carotid artery, including blister-like aneurysms, possess unique clinical and technical features. This report presents nine consecutively managed patients with these types of aneurysm, detailing the clinical and radiological characteristics and surgical outcomes. The initial angiography identified aneurysmal lesions in six of the nine patients with two of these patients requiring additional three-dimensional (3D) angiography. In three patients the aneurysm was only diagnosed on second or third angiograms. Six patients had blister-like aneurysms, and two had saccular-shaped aneurysms diagnosed on the basis of intraoperative findings. One patient with a saccular aneurysm died without surgery. Eight patients underwent a microsurgical procedure: clipping in five, clipping on wrapping with suturing in two and trapping in one. Three of these eight patients had an intraoperative rupture. A favorable outcome was obtained in seven patients. Advances in microsurgical techniques to prevent premature rupture and 3D radiological diagnosis with careful pre-operative consideration of the surgical strategies will be required for a further improvement of the clinical outcome.

Angiographic revascularization of the brain after encephaloduroarteriosynangiosis: a case report.

Preoperative and postoperative angiograms of a 13-year-old Japanese girl with moyamoya disease are compared. She underwent an indirect extracranial/intracranial bypass operation called encephaloduroarteriosynangiosis (EDAS). Post-EDAS angiograms clearly show revascularization of the brain through the donor scalp artery and decrease in moyamoya vessels, leptomeningeal anastomoses, and preexisting spontaneous transdural anastomoses.

Decompressive craniectomy after intravenous tissue plasminogen activator administration for stroke

OBJECTIVE Intravenous tissue plasminogen activator (IV tPA) is an approved treatment for acute ischemic stroke. However, the effects of decompressive craniectomy (DC) after IV tPA administration for ischemic stroke are still largely unknown. The aim of this study was to investigate the safety and outcomes of DC after IV tPA administration. METHODS We retrospectively reviewed patients who underwent DC for malignant hemispheric infarction. We compared 20 patients who underwent DC after IV tPA administration with another 20 patients who underwent DC without prior IV tPA administration. RESULTS The patient characteristics did not differ between the DC patients with and without prior IV tPA administration. New intracranial bleeding or worsening of pre-existing ICH occurred in two patients (10%) in each group. Furthermore, the rates of an mRS score of 4-6, 5 or 6, and 6 did not differ significantly between the two groups. CONCLUSION DC may be a safe and useful surgical procedure for space-occupying edema after IV tPA administration for acute stroke.

Clinical characteristics and surgical outcomes of patients with aneurysmal subarachnoid hemorrhage and acute subdural hematoma undergoing decompressive craniectomy.

OBJECTIVE This report presents 12 consecutively managed patients with aneurysmal subarachnoid hemorrhage (SAH) associated with acute subdural hematoma (ASDH) who underwent decompressive craniectomy (DC) with special attention to their clinical characteristics and surgical outcomes. METHODS We retrospectively reviewed medical charts, radiologic findings, surgical notes, and video records. RESULTS Among these 12 patients (mean age 59.1 years, 4 men, 8 women), the Hunt and Kosnik clinical grade was grade V in 7 patients (58.3%), grade IV in 2 patients (16.7%), grade III in 2 patients (16.7%), and grade II in 1 patient (8.3%). The aneurysms were located on the internal carotid artery in four patients, the middle cerebral artery in six patients, and the anterior communicating artery in two patients. Computed tomography findings on admission revealed ASDH in all patients. In addition, SAH was seen in 11 patients. An intracerebral hematoma was found in eight patients, intraventricular hemorrhaging occurred in four, and an acute hydrocephalus was seen in one patient. All patients underwent a microsurgical clipping procedure and an additional DC. Symptomatic vasospasm was confirmed in six (50%), and eight patients with chronic hydrocephalus received a ventriculoperitoneal shunt (67%). The Glasgow Outcome Scale at discharge showed good recovery in five patients (41.7%), severe disability in four (33.3%), vegetative state in two (16.7%), and death in one patient (8.3%). A favorable outcome was achieved in five patients (41.7%). CONCLUSIONS We suggest that the DC was effective for reducing morbidity and mortality in poor grade patients with SAH presenting with ASDH.

Hemorrhagic encephalitis associated with Epstein-Barr virus infection

Epstein-Barr virus (EBV) encephalitis is a rare neurological complication, usually only reported in pediatric patients. We present a 20-year-old, previously healthy male who developed hemorrhagic encephalitis caused by EBV. He was admitted to our hospital with a 1-week history of fever, diarrhea, headache, and confusion. Brain T2-weighted MRI showed a focal area of increased signal in the right temporal lobe. Brain MRI and CT scans on day 2 revealed progression of the lesion, with partial hemorrhagic change, acute brain swelling, and severe midline shift. The patient underwent external decompression and external ventricular drainage. EBV DNA was identified in brain biopsy specimens by polymerase chain reaction. The postoperative course was uneventful. To our knowledge, this is the second report of hemorrhagic EBV encephalitis in an adult.

Prognosis for Severe Traumatic Brain Injury Patients Treated with Bilateral Decompressive Craniectomy

PURPOSE Decompressive craniectomy for traumatic brain injury patients has been shown to reduce intracranial hypertension, while it often results in increased brain edema and/or contralateral space-occupied hematoma. The purpose of this study was to determine the prognosis of bilateral decompressive craniectomy in severe head injury patients with the development of either bilateral or contralateral lesions after ipsilateral decompressive craniectomy. METHODS Twelve patients underwent bilateral decompressive craniectomy among 217 individuals who had been treated with decompressive craniectomy with dural expansion from September 1995 to August 2006. The following patient data were retrospectively collected: age, neurological status at admission, time between injury and surgical decompression, time between first and second decompression, laboratory and physiological data collected in the intensive care unit, and outcome according to the Glasgow Outcome Scale. RESULTS Patient outcomes fell into the following categories: good recovery (three patients); mild disability (one patient); severe disability (two patients); persistent vegetative state (one patient); and death (five patients). Patients with good outcomes were younger and had better pupil reactions and neurological statuses on admission. Other factors existing prior to the operation did not directly correlate with outcome. At 24 h post-surgery, the average intercranial pressure (ICP), cerebral perfusion pressure (CPP), glucose level, and lactate level in patients with poor outcomes differed significantly from those of patients with a good prognosis. CONCLUSION Head injury patients with either bilateral or contralateral lesions have poor prognosis. However, bilateral decompressive craniectomy may be a favorable treatment in certain younger patients with reactive pupils, whose ICP and CPP values are stabilized 24 h post-surgery.