Spatial relationship between cerebral microbleeds, moyamoya vessels, and hematoma in moyamoya disease.

BACKGROUND: Adult moyamoya disease (MMD) is known to have high incidence of cerebral microbleeds (cMBs); however, the clinical significance still remains unclear. We investigated the frequency of cMBs in a large number of patients and analyzed the patterns of MB distribution in association with the location of the hematoma and moyamoya vessels. METHODS: We studied 259 consecutive patients with MMD using prospectively collected database. One hundred ninety-one patients were eligible for the present study, and image analysis was performed retrospectively. The presence of cMBs and remains of hemorrhage were determined using gradient-echo T2*-weighted sequence (1.5 T). The development of moyamoya vessels was assessed on source images of time-of-flight magnetic resonance angiography. The analysis consists of descriptive assessment of the spatial relationship between cMB, remains of hemorrhage, and moyamoya vessels. Statistical analysis was performed to calculate relative risk ratio in the presence of cMBs in relation to the remains of hemorrhage (macrohematoma), age of onset, and the presence of concomitant moyamoya vessels. RESULTS: Thirty MBs were observed in 20 adult MMD patients (16.9%). MBs were located predominantly in the periventricular white matter (63.3%) followed by the basal ganglia/thalami (20%). Comparing the patients with cMBs from those without, hematoma was more frequently observed in patients with cMBs (odds ratio [OR] 4.29; 95% confidence interval [CI] 1.58-11.62; P=.0062). Patients with adult onset was more likely to demonstrate cMBs (14.4%) compared with the patients with pediatric onset (4.1%) (OR 3.93; 95% CI 1.11-13.91). Moyamoya vessels appeared in the lateral part of the trigon, and the periventricular white matter was significantly associated with the presence of cMBs (lateral part of the trigon; OR 3.29 [1.59-6.82], P=.0019, periventricle of the body of lateral ventricle; OR 2.40 [1.20-4.79], P=.0214, respectively). cMBs accompanied concomitant arteries in 23 (76.7%) lesions. The subependymal-leptomeningeal artery anastomosis was the most common pattern (n=20, 66.7%). CONCLUSIONS: Spatial relationship was demonstrated between the moyamoya vessels and perivascular hemosiderin deposition particularly around the subependymal-leptomeningeal anastomosis, suggesting the mechanism for the development of cMBs in MMD. Present study further supports previous findings that cMBs potentially serve as a marker for the bleeding-prone microangiopathy in MMD. The significance of the present study lies in selecting optimal surgical candidate for preventing future hemorrhage by the presence of the cMBs, whereas current surgical indication relying on the degree of ischemia frequently fails to detect patients with future hemorrhage.

[Bilateral abducens nerve palsies in treated cases of subarachnoid hemorrhage].

Isolated abducens nerve palsies associated with the rupture of intracranial aneurysms have rarely been reported. We report two cases of isolated bilateral abducens nerve palsies occurring after subarachnoid hemorrhage due to the rupture of an intracranial aneurysm. Case 1: A 49-year-old woman had bilateral abducens nerve palsies following subarachnoid hemorrhage due to the rupture of the left vertebral artery-posterior inferior cerebellar artery aneurysm. Case 2: A 55-year-old man had bilateral abducens nerve palsies following subarachnoid hemorrhage due to dissecting aneurysm of the right vertebral artery. Case 1 and 2 were treated with surgical clipping of the aneurysm and internal occlusion of the parent artery. In both cases, bilateral abducens nerve palsies achieved almost full recovery several months after treatment. It is speculated that the main causes of palsies are compression and stretching of the bilateral abducens nerves by a thick clot in the prepontine cistern. Although most of the abducens palsies may be reversible and have good prognosis, it is important that they are kept in mind as isolated symptoms of subarachnoid hemorrhage.

[Peritoneal catheter placement into the suprahepatic space: a report of 2 cases with abdominal complications of ventriculoperitoneal shunts].

Complications arising from the placement of ventriculoperitoneal shunts are common. These complications may be related to a number of causes and present with various symptoms. Of these, abdominal complications such as formation of intraperitoneal pseudocysts and abdominal abscesses possibly recur, but, alternative sites for placing the peritoneal catheter of ventriculoperitoneal shunts are limited. We present two cases of ventriculoperitoneal shunt malfunctioning due to repeated abdominal complications. The location of the peritoneal end of the shunt was successfully revised to the suprahepatic space in the peritoneal cavity. We describe the clinical course of these two cases in this report, along with a precise technique of placing the peritoneal end of the shunt into the suprahepatic space. In addition, we will discuss the validity of this space as an alternative site for the placement of the peritoneal end of the ventriculoperitoneal shunt.