An Ap/T-MCA is a rare anomaly and should be differentiated from moyamoya conditions and degenerative steno-occlusive diseases of the middle cerebral artery. Coexisting anomalies of the anterior or middle cerebral arteries are frequent. This anomaly is vulnerable to both hemorrhagic and ischemic strokes.

ObjectiveAlthough burr hole trephination is a safe and effective surgical option to treat patients with chronic subdural hematoma (CSDH), it often results in a small but undesirable scalp depression from burr hole defect. This study is to evaluate the efficacy of titanium burr hole cover (BHC) for reconstruction of skull defects in these patients.MethodsA hundred and ninety-six cases of burr hole trephinations for CSDHs between January 2009 and December 2013 were assigned into two groups; Gelfoam packing only (GPO) and reconstruction using titanium BHC group, according to the modalities of burr hole reconstructions. The incidences and depths of scalp depressions and incidences of postoperative complications such as infections or instrument failures were analyzed in both groups. We also conducted telephone surveys to evaluate the cosmetic and functional outcomes from patient's aspect.ResultsSignificantly lower incidence (p<0.0001) and smaller mean depth (p<0.0001) of scalp depressions were observed in BHC than GPO group. No statistical differences were seen in postoperative infection rates (p=0.498) between the two groups. There were no instrument failures in BHC group. According to the telephone surveys, 73.9% of respondents with scalp depressions had cosmetic inferiority complexes and 62.3% experienced functional handicaps during activities of daily life.ConclusionTitanium BHC is highly effective for reconstruction of skull defect after burr hole trephination of CSDH, and provides excellent cosmetic and functional outcomes without significant complications.

Electrochemical properties and gas evolution behavior of Li 2 NiO 2 are studied. In-situ gas evolution test of Li 2 NiO 2 cell shows that large amount of gas is evolved during the first delithiation process at two characteristic potential levels of about 3.6 V and 4.13 V vs. Li/Li + for small gas and severe gas generation, respectively. In-situ XRD and EXAFS analyzes reveal that the small gas generation is related to the bulk structural collapse of Li 2 NiO 2 during phase transformation, while the severe gas generation results from the material decomposition of structurally unstable phase after the phase transformation. 3 wt% Al 2 O 3 coated Li 2 NiO 2 shows improved gas evolution properties.

ObjectiveKeyhole craniotomy is a modification of pterional craniotomy that allows for use of a minimally invasive approach toward cerebral aneurysms. Currently, mini-pterional (MPKC) and supraorbital keyhole craniotomies (SOKC) are commonly used. In this study, we measured and compared the geometric configurations of surgical exposure provided by MPKC and SOKC.MethodsNine patients underwent MPKC and four underwent SOKC. Their postoperative contrast-enhanced brain computed tomographic scans were evaluated. The transverse and longitudinal diameters and areas of exposure were measured. The locations of the anterior communicating artery, bifurcation of the middle cerebral artery (MCAB), and the internal carotid artery (ICA) terminal were identified, and the working angles and depths for these targets were measured.ResultsNo significant differences in the transverse diameters of exposure were observed between MPKC and SOKC. However, the longitudinal diameters and the areas were significantly larger, by 1.5 times in MPKC. MPKC provided larger operable working angles for the targets. The angles by MPKC, particularly for the MCAB, reached up to 1.9-fold of those by SOKC. Greater working depths were required in order to reach the targets by SOKC, and the differences were the greatest in the MCAB by 1.6-fold.ConclusionMPKC provides larger exposure than SOKC with a similar length of skin incision. MPKC allows for use of a direct transsylvian approach, and exposes the target in a wide working angle within a short distance. Despite some limitations in exposure, SOKC is suitable for a direct subfrontal approach, and provides a more anteromedial and basal view. MCAB and posteriorly directing ICA terminal aneurysms can be good candidates for MPKC.

A fenestrated middle cerebral artery (MCA) is a rare congenital anomaly, and is related to interference in the normal embryonic development of the MCA. Fenestrated MCA has been regarded to have no clinical significance other than a rare event of hemorrhage from associated aneurysm. However, the fenestration within the arterial trunk can be an obstacle against thrombus migration and may be associated with a major cerebral infarction. Moreover, the presence of this anomaly can be hardly detected prior to thrombolytic procedures, and emergent treatments are proceeded without any information of anatomical configurations. Therefore, the recanalization procedures would carry a high risk of intraprocedural complications. We report a rare case of MCA territory infarction from occlusion of fenestrated M1 segment, and also introduce a safe method of mechanical thrombolysis using coil.

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ObjectivePatients with traumatic acute subdural hematoma (ASDH) often require surgical treatment. Among patients who primarily underwent craniotomy for the removal of hematoma, some consequently developed aggressive intracranial hypertension and brain edema, and required secondary decompressive craniectomy (DC). To avoid reoperation, we investigated factors which predict the requirement of DC by comparing groups of ASDH patients who did and did not require DC after craniotomy.MethodsThe 129 patients with ASDH who underwent craniotomy from September 2007 to September 2017 were reviewed. Among these patients, 19 patients who needed additional DC (group A) and 105 patients who underwent primary craniotomy only without reoperation (group B) were evaluated. A total of 17 preoperative and intraoperative factors were analyzed and compared statistically. Univariate and multivariate analyses were used to compare these factors.ResultsFive factors showed significant differences between the two groups. They were the length of midline shifting to maximal subdural hematoma thickness ratio (magnetization transfer [MT] ratio) greater than 1 (p<0.001), coexistence of intraventricular hemorrhage (IVH) (p<0.001), traumatic intracerebral hemorrhage (TICH) (p=0.001), intraoperative findings showing intracranial hypertension combined with brain edema (p<0.001), and bleeding tendency (p=0.02). An average value of 2.74±1.52 was obtained for these factors for group A, which was significantly different from that for group B (p<0.001).ConclusionAn MT ratio >1, IVH, and TICH on preoperative brain computed tomography images, intraoperative signs of intracranial hypertension, brain edema, and bleeding tendency were identified as factors indicating that DC would be required. The necessity for preemptive DC must be carefully considered in patients with such risk factors.

Infraoptic anterior cerebral artery (ACA) is an extremely rare congenital anomaly. This anomalous artery usually arises from the intradural internal carotid artery (ICA) near the level of the ophthalmic artery (OA) or rarely from the extradural ICA. This anomaly frequently harbors a cerebral aneurysm, and may involve other coexisting vascular anomalies. In the case of this anomaly, surgical treatment of the aneurysm at the proximal ACA or anterior communicating artery (ACoA) may sometimes be difficult, because the veiled proximal ACA by the optic nerve would make proximal control inconvenient and the vertical midline segment of the proximal ACA would frequently form a superiorly directing aneurysm with a relatively high position. We report on an extremely rare case of a ruptured aneurysm at the infraoptic azygous ACA, possibly having an extradural origin, accompanied by contralateral ICA agenesis, and also introduce a feasible method for treatment by Y-stent assisted coil embolization.