Yoshiharu Matsushima

A new surgical treatment of moyamoya disease in children: A preliminary report

A new operative method, encephalo-duro-arterio-synangiosis, for the surgical treatment of pediatric moyamoya disease has been developed. The rationale of the operation is to help promote the natural tendency of this disease to develop cerebrovascular collaterals. The method is to transplant a scalp artery with a strip of galea, leaving the distal as well as the proximal arteries intact, to a narrow linear dural opening made under an osteoplastic craniotomy. A representative case is described and the operative procedure is outlined. Our new method is compared with other surgical treatments of this disease.

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.

Surgically induced angiogenesis to compensate for hemodynamic cerebral ischemia.

Background and Purpose The ischemic brain may stimulate angiogenesis to compensate for impaired circulation. We examined the conditions promoting such angiogenesis to provide the basis for surgical treatment. Methods The degree of cerebral hemodynamic stress was studied in patients with moyamoya disease using the stable xenon-enhanced computed tomographic acetazolamide tolerance test and positron emission tomography. Patients were subjected to surgery in which scalp arteries were placed on the cerebral cortex without vessel-to-vessel anastomosis. Formation of the newly vascularized collateral network connecting the implanted artery to cortical arteries was assessed angio-graphically 12 to 17 months after surgery. Results Preoperative average resting cerebral blood flow for cortex that developed revascularization of cortical arteries was not significantly different from that for cortex that did not. However, cortex that developed revascularization had an average preoperative increase of blood flow by acetazolamide tiveincreasetreatment of −3.29±4.6 mL/min per 100 cm3 (n=20), which was significantly less (P=.0034) than that of cortex that did not show revascularization (20.7±4.3 mL/min per 100 cm3; n=9). Good revascularization developed when the cortex showed increase of blood flow by acetazolamide treatment of less than 0 (steal phenomenon). Preoperative positron emission tomography data indicated that revascularization developed when the cortex was under “misery perfusion.” Postoperative hemo-dynamics were ameliorated by revascularization. Conclusions Angiogenesis to connect the implanted scalp arteries to the cerebral cortical arteries was selectively initiated when ischemia of hemodynamic origin existed.

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.

Severe haemodynamic stress in selected subtypes of patients with moyamoya disease: a positron emission tomography study

Background: The optimum management of patients with moyamoya disease remains controversial. Objectives: To examine retrospectively the correlation between the degree of haemodynamic stress and the clinical presentation by measuring cerebral haemodynamics and metabolism using positron emission tomography (PET). Methods: 57 patients with moyamoya disease (mean age 32 years, range 12 to 64), classified into five groups according to clinical manifestations, underwent PET measurement of cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral metabolic rate for oxygen (CMRo2), and oxygen extraction fraction (OEF) using 15O labelled gases. The regional values in patient groups were compared with a normal group. Results: CBF in non-symptomatic patients, patients presenting with transient ischaemic attacks (TIA), and patients with haemorrhagic onset (H) was not significantly lower than in normal controls in any region. CBV in the TIA group and in patients with infarction associated with TIA (I/TIA) was significantly higher than in the controls in most regions. OEF in the frontal, parietal, and temporal cortex was significantly higher in the I/TIA group than in the controls. Patients in the H group and those with a permanent deficit with infarction (PD group) had decreased metabolism with normal OEF. Multivariate analysis to test the distribution of the three dimensional vector (CBF, CBV, OEF) showed significant differences between every possible pair among the six groups except NS v H and H v PD in the frontal cortex. Conclusions: The haemodynamic status of moyamoya disease is not uniform, and severe haemodynamic stress occurs in selected subgroups of patients.

Moyamoya Disease in Children and Its Surgical Treatment

Moyamoya disease is an unusual form of chronic cerebrovascular occlusive disease characterized usually by bilateral stenosis of distal internal carotid arteries and their vicinity, by a hazy network of collateral circulation at the base of the brain called moyamoya vessels and clinically by recurring hemispheric ischemic attacks in children. This disease was first reported by a Japanese neurosurgeon and many reports and studies on this disease have been published in Japan. We report here the recent progress in the diagnosis of the disease and introduce a newly developed operative procedure which we think is an ideal surgical method for treating this disease in children.

Chronic subdural haematoma preceded by persistent traumatic subdural fluid collection.

The role of traumatic subdural fluid collections in the development of chronic subdural haematomas was studied in 43 of 715 patients who underwent a CT scan because of a recent head injury. Twenty of the 43 patients subsequently developed a chronic subdural haematoma, and this occurred especially in the aged. Nearly 50% of patients with asymptomatic or minimally symptomatic subdural fluid collection may develop a chronic subdural haematoma.

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.

Renal artery lesions in patients with moyamoya disease: angiographic findings.

BACKGROUND AND PURPOSE Renal artery lesions in moyamoya disease have been described sporadically in several case reports. The purpose of this study is to evaluate the angiographic findings of renal artery lesions in moyamoya disease and to determine the prevalence of renal artery lesions in patients with moyamoya disease. METHODS Eighty-six consecutive patients with idiopathic moyamoya disease were prospectively examined with both cerebral angiography and abdominal aortography. The findings of abdominal aortography were reviewed for the presence and appearance of renal artery lesions and compared with the clinical data and cerebral angiographic findings. RESULTS Of 86 patients with idiopathic moyamoya disease, 7 patients (8%) were found to have renal artery lesions. Six patients (7%) had stenosis in the renal artery, and 1 patient (1%) had a small saccular aneurysm in the renal artery. Two patients (2%) with a marked renal artery stenosis presented with renovascular hypertension, which resulted in an intraventricular hemorrhage in 1 patient. Furthermore, the renal artery stenosis in the 2 patients with renovascular hypertension was successfully treated with percutaneous transluminal angioplasty. There was no significant correlation between the presence of renal artery lesions and cerebral angiographic findings. CONCLUSIONS Seven (8%) of 86 patients with moyamoya disease showed renal artery lesions, including 6 stenoses (7%) and 1 aneurysm (1%). Renal artery lesions are a clinically relevant systemic manifestation in patients with moyamoya disease.

Early Development of Intimal Thickening in Superficial Temporal Arteries in Patients With Moyamoya Disease

BACKGROUND AND PURPOSE Moyamoya disease is a progressive cerebrovascular occlusive disease that occurs in children. The etiology is unknown. We examined the superficial temporal arteries from patients with moyamoya disease, particularly children, to determine whether the extracranial arteries as well as the intracranial arteries are involved in this disease. METHODS Small branches of the superficial temporal arteries were obtained from 22 patients with moyamoya disease during indirect arterial bypass surgery. Histological examinations were performed, and the findings were compared with those of arteries from 12 control patients. RESULTS Intimal thickening was observed in 9 of 17 patients with moyamoya disease younger than 20 years but in none of 7 control patients under the age of 20 years (P < .02, Fishers exact test). Intimal thickening appeared from age 20 years in control patients. The arteries of moyamoya patients showed fibrocellular intimal thickening with a paucity of lipid. The arteries from moyamoya patients contained strongly stained multilayered elastic fibers in the thickened intima, while those from control patients showed only weakly stained elastic fibers in the intima. CONCLUSIONS Our findings suggest that moyamoya disease is a systemic vascular disease. The results indicate systemic etiologic factors that may promote the early development of intimal thickening in moyamoya disease.