[A Case of Segmental Arterial Mediolysis:Subarachnoid Hemorrhage Followed by Abdominal Bleeding].

We describe a case involving subarachnoid and intraperitoneal hemorrhage due to segmental arterial mediolysis(SAM). A 77-year-old female patient with sudden subarachnoid hemorrhage was immediately transferred to our institution. The hemorrhage was classified as grade 2 according to the World Federation of Neurosurgical Societies system. The patient was a non-smoker and did not drink alcohol regularly. A right internal carotid aneurysm was detected using CT angiography and was clipped during frontotemporal craniotomy. Bleeding was observed from the anterior wall of the internal carotid artery, and the tear was clipped. The patient had an uneventful postoperative course until sudden cardiopulmonary arrest eight days after craniotomy. She died of massive intraperitoneal hemorrhage. Autopsy revealed that the hemorrhage was due to dissection of the celiac artery. Tunica media denaturation was observed not only in the celiac artery, but also in the splenic and internal carotid arteries, which exhibited ruptured aneurysms, and the patient was diagnosed with segmental arterial mediolysis(SAM). SAM is an arterial degenerative disease affecting the medial layer of the arterial and dissecting walls. Multiple lesions are sometimes found. Radiographic imaging findings of SAM are similar to those of dissecting aneurysms, which are characterized by a single continuous dissection of the medial layer. As observed in this case, abdominal bleeding caused by SAM can occur after intracranial bleeding. When surgeons encounter unusual intracranial dissecting aneurysms, SAM should be considered as a differential diagnosis.

[Radiation-Induced Malignant Peripheral Nerve Sheath Tumor of the High Cervical Spine].

UNLABELLED: CASE: A 30-year-old woman presented with posterior cervical pain and left-sided omalgia. The patient had a history of non-Hodgkin's lymphoma for which she had received prophylactic whole-brain irradiation(including at the upper cervical level)17 years previously. A magnetic resonance imaging(MRI)scan obtained 1 month previously showed an intradural extramedullary mass lesion at the left C1/2 level. We initially considered the tumor to be a benign schwannoma, but the patient subsequently developed left hemiparesis and was consequently admitted 2 days after her first visit. A second MRI scan showed that the tumor had progressed markedly. Hence, the patient underwent emergency surgical excision of the tumor. However, the tumor could only be partially removed because it had strongly adhered to the ventral aspect of the spinal cord. The tumor was pathologically diagnosed as a malignant peripheral nerve sheath tumor(MPNST). The residual tumor was subjected to local irradiation and surgery, but the treatment was unsuccessful, and the patient died on the 91st day of her illness. Conclusion:We report a case of radiation-induced high cervical MPNST arising from a benign schwannoma. All 9 previously reported cases of radiation-induced spinal MPNST were reviewed. Intraspinal MPNST of the high cervical region are extremely rare and are associated with a very poor prognosis. The 5-year survival rate of such tumors is markedly worse than that of other types of MPNST, and no standard treatment has been established for this condition.

A Simple Procedure of Epidural Electrode Lead Replacement through a Tissue Sheath in Spinal Cord Stimulation.

Spinal cord stimulation (SCS) is widely performed to treat several types of intractable chronic pain. To maintain lasting SCS, epidural electrode leads must be replaced sometimes due to problems like lead breakage. However, in lead replacement, guiding the new lead to the original position may be difficult because granulation tissue sheath forms around the lead. We encountered a surgical case where we inserted new leads through tissue sheaths forming around the old leads from the epidural space to the thoracolumbar fascia; the lead was smoothly introduced to the original place. This procedure is simpler than previously reported techniques. Here, we report the detailed surgical procedure and review the relevant literature.

Whole-exome sequencing in a Japanese multiplex family identifies new susceptibility genes for intracranial aneurysms.

BACKGROUND: Intracranial aneurysms (IAs) cause subarachnoid hemorrhage, which has high rates of mortality and morbidity when ruptured. Recently, the role of rare variants in the genetic background of complex diseases has been increasingly recognized. The aim of this study was to identify rare variants for susceptibility to IA. METHODS: Whole-exome sequencing was performed on seven members of a Japanese pedigree with highly aggregated IA. Candidate genes harboring co-segregating rare variants with IA were re-sequenced and tested for association with IA using additional 500 probands and 323 non-IA controls. Functional analysis of rare variants detected in the pedigree was also conducted. RESULTS: We identified two gene variants shared among all four affected participants in the pedigree. One was the splicing donor c.1515+1G>A variant in NPNT (Nephronectin), which was confirmed to cause aberrant splicing by a minigene assay. The other was the missense p.P83T variant in CBY2 (Chibby family member 2). Overexpression of p.P83T CBY2 fused with red fluorescent protein tended to aggregate in the cytoplasm. Although Nephronectin has been previously reported to be involved in endothelial angiogenic functions, CBY2 is a novel molecule in terms of vascular pathophysiology. We confirmed that CBY2 was expressed in cerebrovascular smooth muscle cells in an isoform2-specific manner. Targeted CBY2 re-sequencing in additional case-control samples identified three deleterious rare variants (p.R46H, p.P83T, and p.L183R) in seven probands, showing a significant enrichment in the overall probands (8/501) compared to the controls (0/323) (p = 0.026, Fisher's extract test). CONCLUSIONS: NPNT and CBY2 were identified as novel susceptibility genes for IA. The highly heterogeneous and polygenic architecture of IA susceptibility can be uncovered by accumulating extensive analyses that focus on each pedigree with a high incidence of IA.

Cerebral vasospasm and hypoperfusion after traumatic brain injury: Combined CT angiography and CT perfusion imaging study.

BACKGROUND: Timely identification of the cerebral perfusion abnormalities after traumatic brain injury (TBI) is highly important. The objective of this study was the evaluation of the post traumatic vasospasm and cerebral hypoperfusion with the serial combined CT angiography (CTA) and CT perfusion (CTP) imaging examinations. METHODS: The case series comprised 25 adult patients with closed TBI accompanied by various types of intracranial hematoma. Emergency surgery was done in 15 cases (60%). Combined CTA and CTP were performed on days 0 (D0) and 7 ± 1 (D7) after trauma. RESULTS: CTA on D0 did not demonstrate vasospasm in any case but revealed it on D7 in 9 patients (36%). In the multivariate analysis, only the presence of subarachnoid hemorrhage (SAH) on D7 had confirmed a significant association with the development of vasospasm (P = 0.0201). Cerebral hypoperfusion at least in one evaluated brain region was noted on D0 and D7 in 76% and 60% of patients, respectively, and showed highly variable spatial distribution and temporal development. Treatment results were not associated with the presence of vasospasm (P = 0.7337) or the number of brain regions affected by hypoperfusion on D0 (P = 0.2285), but the number of brain regions affected by hypoperfusion on D7 was significantly greater in cases of unfavorable outcome (P = 0.0187). CONCLUSION: Vasospasm is merely related to SAH sustained at the subacute stage of TBI, but its spatial and temporary interrelationships with the post traumatic cerebral hypoperfusion are complex. Serial combined CTA and CTP examinations may facilitate monitoring of perfusion abnormalities and treatment guidance.

Identification of shared genomic aberrations between angiomatous and microcystic meningiomas.

BACKGROUND: Angiomatous and microcytic meningiomas are classified as rare subtypes of grade I meningiomas by World Health Organization (WHO). They typically exhibit distinct histopathological features as indicated by their WHO titles; however, these angiomatous and microcystic features are often intermixed. Recently, angiomatous meningiomas were reported to show characteristic chromosomal polysomies unlike the other WHO grade I meningiomas. In the present study, we hypothesize that microcystic meningiomas share similar cytogenetic abnormalities with angiomatous meningioma. METHODS: We performed copy number analysis using single nucleotide polymorphism (SNP) arrays for three angiomatous and eight microcystic meningiomas. Of these, three angiomatous and three microcystic meningiomas were also analyzed by whole exome sequencing and RNA sequencing. RESULTS: We first analyzed three angiomatous and three microcystic meningiomas for which both frozen tissues and peripheral blood were accessible. Copy number analysis confirmed previously reported multiple polysomies in angiomatous meningiomas, which were entirely replicated in microcystic meningiomas when analyzed on different analytical platforms with five additional samples prepared from formalin-fixed paraffin-embedded tumors. Polysomy of chromosome 5 was found in all cases, along with chromosome 6, 12, 17, 18, and 20 in more than half of the cases including both angiomatous and microcystic meningiomas. Furthermore, next generation sequencing did not reveal any distinctive somatic point mutations or differences in gene expression characterizing either angiomatous or microcystic meningiomas, indicating a common genetic mechanism underlying tumorigenesis. CONCLUSIONS: Angiomatous and microcystic meningiomas have substantially similar genetic profiles represented by the characteristic patterns of multiple polysomies originating from chromosome 5 amplification.

A case report of adult cerebellar high-grade glioma with H3.1 K27M mutation: a rare example of an H3 K27M mutant cerebellar tumor.

Diffuse midline glioma, H3 K27M mutant, is newly recognized as a distinct category, which usually arises in the brain stem, thalamus or spinal cord of children, and young adults. The oncogenic H3 K27M mutation involves H3.3 (encoded by H3F3A) or H3.1 (encoded by HIST1H3B/HIST1H3C), and the incidence of each mutation differs among the primary sites. Recently, several papers have reported that cerebellar high-grade gliomas in both children and adults also harbor H3 K27 mutation. With the exception of one pediatric case, all of the cases carried the mutation in H3.3. We herein present the case of an adult cerebellar high-grade astrocytic tumor with H3.1 K27M mutation in a 45-year-old man, which also involvedTP53 mutation and was immunonegative for ATRX. Some groups have reported that H3.3 and H3.1 K27M mutations define subgroups of diffuse intrinsic pontine gliomas (DIPGs) with different phenotypes as well as genetic alterations. On comparing the findings of the present case, particularly TP53 mutation status and ATRX expression, to the findings of the previous studies on DIPGs, our case seems unusual among the H3.1 K27M mutant subgroup. Further studies are needed to clarify the exact frequency, clinicopathological characteristics, and genomic alterations of cerebellar gliomas harboring H3 K27M mutation.

Nonspastic hemifacial spasm confirmed by abnormal muscle responses.

BACKGROUND: Hemifacial spasm is usually diagnosed by inspection which mainly identifies involuntary movements of orbicularis oculi. Assessing abnormal muscle responses (AMR) is another diagnostic method. CASE DESCRIPTION: We report a case of left hemifacial spasm without detectable involuntary facial movements. The patient was a 48-year-old man with a long history of subjective left facial twitching. On magnetic resonance imaging (MRI), the left VIIth cranial nerve was compressed by the left anterior inferior cerebellar artery (AICA), which was in turn compressed by the left vertebral artery. We initially treated him with botulinum toxin. We were able to record AMR, and hemifacial spasm occurred after AMR stimulation, although no spasm was detectable by inspection. Subsequently, we performed microvascular decompression with transposition of the AICA that compressed the VIIth cranial nerve. His hemifacial spasm resolved by 5 weeks after surgery and was not induced by AMR stimulation. CONCLUSION: Hemifacial spasm can sometimes be diagnosed by detecting AMR rather than by visual inspection. We propose that such hemifacial spasm should be termed nonspastic hemifacial spasm.