Tatemi Todaka

Angiographic Dilatation and Branch Extension of the Anterior Choroidal and Posterior Communicating Arteries Are Predictors of Hemorrhage in Adult Moyamoya Patients

Background and Purpose— The cause of intracranial bleeding in moyamoya disease patients is still unknown. To identify factors that contribute to bleeding, we assessed the angiographic findings of moyamoya disease patients. Methods— We examined angiograms obtained from 107 moyamoya patients; 70 manifested ischemic and 37 had hemorrhagic lesions. Patients with intracerebral aneurysms or both hemorrhagic and ischemic lesions in the same cerebral hemisphere were not included. Patients were divided into those <20 years of age (n=47) and those ≥20 years of age (n=60). The right and left hemispheres in each patient were individually classified as hemorrhagic, ischemic, or asymptomatic. Each hemisphere was assessed for dilatation and branch extension of the anterior choroidal artery (AChA) and posterior communicating artery (P-CoM) and for the degree of proliferation of basal moyamoya vessels. These data were then statistically analyzed for correlation with intracranial bleeding events. Results— The degree of proliferation of basal moyamoya vessels was not statistically correlated with hemorrhagic events. On the other hand, there was a correlation between hemorrhage and dilatation and abnormal branching of the AChA. In 27 of 37 hemorrhagic hemispheres (73.0%), this artery was dilated, and its abnormal branches served as collateral supply vessels to other regions. This phenomenon was observed in 4 of 5 hemorrhagic hemispheres from young patients; it was noted in fewer than one third of ischemic and asymptomatic hemispheres from this age group. Similarly, 71.9% of hemorrhagic hemispheres from adult patients manifested AChA dilatation and branching, and the difference between hemorrhagic hemispheres and those that were ischemic or asymptomatic was statistically significant (P <0.01). Although the incidence of dilatation and abnormal branching of the P-CoM was relatively low in hemorrhagic hemispheres from adult patients (18.8%), it was significantly higher than in the ischemic and asymptomatic hemispheres from this age group. Using dilatation and abnormal branching of the AChA and/or P-CoM as assessment criteria, we obtained high specificity (86.4%) and sensitivity (84.4%) for hemorrhagic events in adult moyamoya patients. Conclusions— In adult moyamoya patients, dilatation and abnormal branching of the AChA and/or P-CoM are strong predictors of hemorrhagic events.

Clinical features of aneurysms of the posterior cerebral artery : A 15-year experience with 21 cases

OBJECTIVE:To investigate the characteristic clinical behavior and develop guidelines for the clinical management of posterior cerebral artery aneurysms, we reviewed 21 cases treated during a 15-year period. METHODS:Between 1988 and 2002, we treated 21 patients (10 male, 11 female; mean age, 49.8 yr) with posterior cerebral artery aneurysms at Kumamoto University Hospital and its affiliated hospitals. Data relating to the clinical, radiological, and surgical approaches were analyzed. RESULTS:There were 20 saccular aneurysms, 6 of which were giant or large aneurysms, and 1 dissecting aneurysm. Of the 21 patients, 15 presented with subarachnoid hemorrhage; in 3 patients, an unruptured saccular aneurysm was found incidentally during an evaluation for other cerebral pathological conditions. Two patients presented with progressive homonymous hemianopsia because of the mass effect of the aneurysm, and 1 patient experienced the sudden onset of homonymous hemianopsia because of thrombosis of the aneurysm and afferent artery. Open or endovascular surgery was performed in 19 patients: 14 made a good recovery, 2 had a moderate disability because of angiospasm or infarction after aneurysm trapping, 1 had a severe disability because of angiospasm and cerebral contusion, and 2 died because of severe angiospasm. Of 2 conservatively treated patients, 1 made a good recovery but the other died as a result of rebleeding. CONCLUSION:Posterior cerebral artery aneurysms have specific clinical characteristics compared with aneurysms located elsewhere. The aneurysmal site and size and the surgical technique did not significantly influence treatment outcomes.

Surgical indications to maintain quality of life in elderly patients with ruptured intracranial aneurysms.

OBJECTIVEWe performed a retrospective study to assess long-term outcomes in very old patients with ruptured intracranial aneurysms. The aim of the study was to develop guidelines for choosing surgical or conservative treatment with the goal of maintaining patients’ quality of life. METHODSBetween 1996 and 1999, 76 consecutive patients, aged 80 to 89 years, with ruptured intracranial aneurysms were treated at 18 participating centers. They were divided retrospectively into operated and nonoperated groups, and their preoperative characteristics and treatment outcomes were analyzed. Their Glasgow Outcome Scale and Barthel Index scores at least 2 years after the insult were recorded and analyzed from the perspective of their admission Hunt and Hess grade. RESULTSOur retrospective review encompassed 5.9 years. Of the original 76 patients, 54 (71.1%) died, 13 (17.1%) had a good outcome (Barthel Index ≥60), and 9 (11.8%) had a poor outcome (Barthel Index <60). All patients with Hunt and Hess grades of III or higher at admission had poor outcomes irrespective of treatment. Of 32 patients with an initial Hunt and Hess grade of I or II, 19 (59.4%) underwent surgery; 9 of these patients (47.4%) had good outcomes. Conversely, of 13 nonoperated patients (40.6%), only 2 (15.4%) experienced good outcomes. In seven of the nine operated patients with good outcomes, the aneurysm was small (<12 mm) and located at the internal carotid artery-posterior communicating artery junction. CONCLUSIONOur results suggest that patients in the 9th decade of life with ruptured intracranial aneurysms can be considered for surgical treatment if they have a Hunt and Hess grade of I or II. The highest rate of favorable results was achieved in patients with small internal carotid artery-posterior communicating artery aneurysms.

Analysis of Mean Transit Time of Contrast Medium in Ruptured and Unruptured Arteriovenous Malformations. A Digital Subtraction Angiographic Study

Background and Purpose— To clarify hemodynamic risk factors for hemorrhage in arteriovenous malformations (AVMs), the mean transit time (MTT) of feeding arteries and draining veins in AVMs with and without hemorrhage was measured and analyzed. Methods— Morphological features such as the number and diameter of draining and feeding vessels and the AVM nidus volume were evaluated in 30 patients with supratentorial AVMs. The MTT of feeding arteries and draining veins was measured with the use of time-density curves obtained by digital subtraction angiography. The correlation between hemorrhage and morphology and hemorrhage and MTT was analyzed statistically. Results— The nidus volume was not significantly different between hemorrhagic and nonhemorrhagic AVMs. However, between ruptured and unruptured AVMs there was a significant difference in the mean number of draining veins (1.5±0.69 versus 2.3±0.50; P =0.006), the MTT of the feeding artery (1.10±0.24 versus 1.62±0.55; P =0.03), and the ratio of the MTT of the draining to the feeding vessels (1.71±0.43 versus 1.05±0.07; P <0.001). Conclusions— A high ratio of the MTT of draining veins to feeding arteries suggests disequilibrium between nidal inflow and outflow. The consequent increased pressure in the draining vein may contribute to the development of AVM hemorrhage.

Endovascular coil trapping for ruptured vertebral artery dissecting aneurysms by using double microcatheters technique in the acute stage

Summary¶Background. In the treatment of vertebral artery (VA) dissecting aneurysms, only proximal occlusion of the VA does not necessarily prevent rerupture. We evaluated the efficacy of coil trapping for the ruptured VA dissecting aneurysms using the double microcatheters technique. Methods. We treated 11 patients who presented with subarachnoid haemorrhage (SAH) due to rupture of a VA dissecting aneurysm which did not involve the posterior inferior cerebellar artery at the site of dissection. All patients tolerated the balloon occlusion test. Within 3 days of the SAH, the dissection site was trapped with a Guglielmi detachable coil (GDC) using the double microcatheters technique. The proximal and distal sites of the dissecting aneurysm were embolized simultaneously. Findings. GDC trapping at the affected site was successful in all 11 patients. Radiographic findings showed complete occlusion of the dissection site and patency of the unaffected artery. Although one patient experienced transient dysphagia, there were no major complications. Interpretation. The double microcatheters technique is effective for coil trapping of ruptured VA dissecting aneurysms in selected patients. The risks posed by this simple technique are minimal, even in the acute stage.

Intrathecal Urokinase Infusion Through a Microcatheter into the Cisterna Magna to Prevent Cerebral Vasospasm: Experimental Study in Dogs

BACKGROUND AND PURPOSE Our preliminary report on intrathecal urokinase (UK) infusion into the cisterna magna (CM) with a microcatheter showed good results in terms of vasospasm prevention in humans. In this study, we evaluated the relationship between different urokinase (UK) infusion sites and their effect on vasospasm prevention by using our canine subarachnoid hemorrhage (SAH) model. METHODS At 24 hours after SAH induction, we injected 1000 IU/kg UK into the cisterna magna (CM) or lumbar sac (LS) of dogs by using a microcatheter inserted at the lumbar region. We then obtained serial angiograms and chronologically examined the changes in the mean diameter of the basilar artery (BA) during a 14-day period to determine the effect of the different injection sites on vasospasm prevention. At 24 hours after UK injection, one dog from each group was killed for gross inspection of the subarachnoid clot. To measure its concentration in the CM and sylvian fissure, UK (1000 IU/kg) was injected into the CM or LS of dogs without SAH; measurements were taken at 15-minute intervals until 4 hours after injection. RESULTS At 24 hours after UK injection, subarachnoid clot in front of the brain stem persisted strongly in the LS group; it had almost disappeared in the CM group. In the LS group, there was severe and persistent BA constriction during the 14-day observation period. In the CM group, the BA was constricted on day 3; however, gradual dilatation occurred over time. The mean diameter of the BA on days 7, 10, and 14 was 48.2%, 53.9%, and 58.9% in the LS group and 62.6%, 70.5%, and 82.3% in the CM group. The difference between the two groups was significant on days 7, 10, and 14 (P <.05). In dogs without SAH, the average maximum UK concentration in the CM and the sylvian fissure was 2.5 and 6.7 times higher, respectively, in the CM group than in the LS group. CONCLUSIONS In our canine SAH model, the administration of UK into the CM was significantly more effective in preventing cerebral vasospasms than was administration into the LS.

Meningioma in Down Syndrome

BACKGROUND Down syndrome comprises multiple malformations and is due to trisomy of chromosome 21. There is epidemiologic evidence that individuals with Down syndrome are at decreased risk for solid tumors including brain tumors. It has been suggested that some genes expressed on the extra copy of chromosome 21 act as tumor suppressor genes and contribute to protection against tumorigenesis. CASE DESCRIPTION We report the first case to our knowledge of a patient with Down syndrome, an 8-year-old boy, with an intracranial meningioma, in which the status of chromosome 21 was examined. The diagnosis was based on histologic examination of the surgically resected tumor. Postoperatively, the patients neurologic status improved, and there was no tumor regrowth in the next 2 years. Fluorescence in situ hybridization for chromosome 22 confirmed high allele loss involving the neurofibromin 2 gene locus, a finding typical in meningiomas. Fluorescence in situ hybridization also revealed chromosome 21 heterogeneity in tumor cells; not only cells with trisomy 21 but also cells with disomy and monosomy 21 were present. All blood cells from the patient manifested trisomy 21. CONCLUSIONS Deletion of the chromosome 21 allele may be associated with tumorigenesis of meningioma in Down syndrome. This supports the hypothesis that some genes whose expression is increased on the extra copy of chromosome 21 function as tumor suppressor genes and that they contribute to the reduced tumor incidence in individuals with Down syndrome.

Cosmetic osteoplastic craniotomy with a chisel and hammer.

BACKGROUND Osteoplastic craniotomy has been performed recently with microfixation systems such as miniplates, burr hole buttons, and/or ceramic dust. However, these are costly methods of treatment. Without the use of these devices, we performed cosmetic osteoplastic craniotomy using an inexpensive chisel and hammer. METHODS Our osteoplastic craniotomy with a chisel and hammer was used on 19 lesions in 15 patients. Using a chisel, the bone flap was cut gently from the calvarium to the skull base, the lamina externa to the diploe (finally the lamina interna), and both ends to the midportion between two holes. The lamina interna in the cranium was trimmed easily after removal of the bone flap. The bone defect was minimal because of the absence of a narrow cutting groove and because craniectomy was not performed. The bone flap was replaced by tapping and was tightly fixed. No special fixation system was needed, except for threads. RESULTS Follow-up (mean follow-up, 5 months; range, 5 weeks to 9 months) skull X-ray and 3D-CT showed good fusion and inherent normal configuration of the bone flap. There were two minor dural tears and two minor bony fractures. CONCLUSION A good cosmetic effect without the use of any additional instruments was accomplished with osteoplastic craniotomy using a chisel and hammer.

A novel hybrid biological embolic material : autologous fibroblast incorporated collagen (FC) beads

If viable fibroblasts are used as an active ingredient of an embolic material, it is expected that proliferation and extracellular matrix production of fibroblasts incorporated at a vascular lesion will help restore tissues due to endovascular scar formation, resulting in progressive and permanent occlusion. Based on this working principle, we have devised a novel biological embolic material, hybrid fibroblast incorporated collagen (hybrid FC) beads composed of collagen microbeads and autologous fibroblasts harvested from the subcutaneous tissue of the host to be treated. Hybrid FC beads were prepared by culture of fibroblasts harvested from canine subcutaneous tissue on collagen microbeads (diameters ranging from around 100 µm to around 400 µm). Canine kidneys were embolized with either hybrid FC or cell-free collagen beads via a transarterial route. Histological examination up to 6 months after embolization revealed that, although both embolic materials effectively occluded the target vessels at the time of embolization, intravascular scar formation activity at the embolized sites was much more profound in the case of the hybrid FC beads than in that of the cell-free beads. Proliferation of autologous fibroblasts was verified by the expression of alkaline phosphatase activity of gene-transfected fibroblasts at the site of lodgement of the beads. It is expected that, using the novel hybrid biological embolic material, hybrid FC beads used for vascular lesions such as arteriovenous malformations can be treated more effectively to restore tissues, resulting in minimal recanalization which often occurs when synthetic embolic materials are used. Copyright 1999 Harcourt Publishers Ltd.