小嶋 大二朗

Some patients with cerebral amyloid angiopathy (CAA), which is characterized by amyloid β fibril deposition in cortical and leptomeningeal vessels, develop an inflammatory response, leading to CAA-related inflammation (CAA-RI). In such cases, histopathologically confirmed vasculitis is defined as amyloid β-related angiitis (ABRA). Here, we report the rare case of an 80-year-old woman who presented with anomic aphasia and mild right upper limb weakness. Magnetic resonance imaging revealed restricted diffusion in the subarachnoid space along the cerebral sulci and dura mater, mainly within the left parietal lobe. Additional imaging findings included lobar microbleeds, edematous white matter changes, and leptomeningeal and dural enhancement. Brain biopsy revealed vasculitis with amyloid β deposition, consistent with ABRA. Marked lymphoplasmacytic infiltration, which was present in the leptomeninges and the dural surface, was considered the cause of the subarachnoid diffusion restriction. Immunosuppressive treatment led to clinical and radiological improvement. As illustrated in this case, CAA-RI may present with atypical findings of subarachnoid diffusion restriction and dural involvement, and the recognition of these features, which can mimic rheumatoid meningitis and other inflammatory conditions, is important for differential diagnosis.

Abstract The lateralized efficacy of vagus nerve stimulation (VNS) remains insufficiently explored. We report a case of drug-resistant epilepsy with bilateral frontal lobe seizure onset, treated with left cervical VNS. Preoperative video- electroencephalogram revealed predominant interictal discharges in the right hemisphere and frequent seizures from both hemispheres. Following VNS, overall seizure frequency decreased. Notably, stereo-electroencephalography performed 15 months postoperatively showed a marked reduction in right-sided seizures, while left-sided seizures remained frequent. This case highlights the potential lateralized effect of VNS in a single patient with bilateral frontal lobe epilepsy, suggesting that VNS may preferentially suppress seizures originating from the right hemisphere.

Karnofsky Performance Status (KPS) is a widely used scale to assess performance status. KPS ≥ 50% implies that patients can live at home. Therefore, maintaining KPS ≥ 50% is important to improve the quality of life of patients with glioblastoma, whose median survival is less than 2 years. This study aimed to identify the factors associated with survival time with maintenance of KPS ≥ 50% (survival with KPS ≥ 50%) in patients with glioblastoma, IDH-wildtype. Ninety-eight patients with glioblastomas, IDH-wildtype, who were treated with concomitant radiotherapy (RT) and temozolomide (TMZ) followed by maintenance TMZ therapy, and whose KPS at the start of RT was ≥ 50%, were included. The median survival with KPS ≥ 50% was 13.3 months. In univariate analysis, preoperative KPS (≥ 80%), KPS at the start of RT (≥ 80%), residual tumor size (< 2 cm3), methylated MGMT promotor, and implantation of BCNU wafer were associated with survival with KPS ≥ 50%. In multivariate analysis, KPS at the start of RT (≥ 80%), methylated MGMT promotor, and residual tumor size (< 2 cm3) were significantly associated with increased survival with KPS ≥ 50%. A strategy of maximum possible tumor resection without compromising KPS is desirable to prolong the survival time with KPS ≥ 50%.

BACKGROUND: Diploic veins may act as collateral venous pathways in cases of meningioma with venous sinus invasion. Diploic vein blood flow should be preoperatively evaluated to consider preserving the veins. In this study, we evaluated the use of time-resolved whole-head computed tomography angiography (4D-CTA)-which is less patient-intensive than digital subtraction angiography (DSA)-for assessing diploic vein blood flow and the positional relationship between typical craniotomy approaches and diploic veins. METHODS: We retrospectively examined 231 patients who underwent surgery for intracranial meningioma. We performed contrast-enhanced magnetic resonance imaging (MRI) to evaluate diploic vein pathways and compared the visualization rates of diploic vein blood flow assessed using 4D-CTA and DSA. Subsequently, we evaluated the rates of the diploic veins transected during craniotomy by comparing the pre- and postoperative contrast-enhanced MRI. RESULTS: The diagnostic performance of 4D-CTA was assessed in 45 patients. Of the 320 diploic veins identified in these patients, blood flow in 70 (21.9%) diploic veins was identified by 4D-CTA and DSA, and both results were consistent. To assess the transection rates of the diploic veins, 150 patients were included. A trend towards a high transection rate of the diploic vein in the basal interhemispheric, frontotemporal, orbitozygomatic, combined transpetrosal, and convexity craniotomy approaches was observed. CONCLUSIONS: In patients with meningiomas, both 4D-CTA and DSA are useful in evaluating diploic vein blood flow. In meningiomas with venous sinus invasion, determining the extent of craniotomy after understanding the pathways and blood flow of diploic veins is recommended.

Most osteomalacia-inducing tumors (OITs) are phosphaturic mesenchymal tumors (PMTs) that secrete fibroblast growth factor 23 (FGF23). These tumors usually occur in the bone and soft tissues, and intracranial OITs are rare. Therefore, intracranial OIT is difficult to diagnose and treat. This paper presents a case of intracranial OIT and shows a review of previous cases. A 45-year-old man underwent nasal cavity biopsy and treatment with active vitamin D3 and neutral phosphate for hypophosphatemia. Amplification of FGF23 mRNA level within the tumor was detected. Subsequently, the surgical specimen was diagnosed with a PMT and was considered the cause of the patient's osteomalacia. The patient was referred to a neurosurgery department for the excision of the intracranial tumor extending to the nasal cavity. After tumor removal, the serum levels of FGF23 and phosphorus were normalized as compared to preoperative those. The patient remains disease-free, without additional treatment, approximately 10 years after surgery, with no tumor recurrence. As per the literature, intracranial OITs usually occur in patients aged 8-69 years. Bone and muscle pain are major complaints. Approximately 60% of the patients reported previously had symptoms because of intracranial tumors. In some cases, it took several years to diagnose OIT after the onset of the osteomalacia symptoms. Laboratory data in such cases show hypophosphatemia and elevated FGF23 levels. Because FGF23 levels are associated with the severity of osteomalacia symptoms, total tumor resection is recommended. PMT and hemangiopericytoma (HPC) are histologically similar, but on immunochemistry, PMT is negative for signal transducer and activator of transcription 6 (STAT6), whereas HPC is positive. FGF23 amplification is seen in PMTs but not in HPCs. Therefore, the analysis of FGF23 and STAT6 was helpful in distinguishing PMTs from HPCs. In cases of hypophosphatemia and osteomalacia without a history of metabolic, renal, or malabsorptive diseases, the possibility of oncogenic osteomalacia should be considered.

近年，細菌性脳膿瘍の予後は，外科手術や抗生剤の進歩とともに改善されつつあるが，依然として死亡率は10‒20％と高く，重度の後遺症を生じ得る致死的疾患である．また，抗生剤の選択や投与期間，外科治療のタイミングや術式など，良好な予後につなげるには未だに不明な点が多く，標準的治療は確立されていない．2014年４月から2021年３月までの７年間に，２施設の地域医療支援病院において細菌性脳膿瘍の治療を行った患者を対象に，臨床的特徴と治療成績を後方視的に評価し，転帰に関連する因子を比較検討した．条件を満たした合計20例を対象に，平均年齢は66.7±15.8歳，男女比は３：１だった．脳膿瘍の治療として14例（70％）に外科手術が施行され，６例（30％）は抗生剤治療のみで加療した．起因菌は，15例（75％）の患者で分離同定され，推測される脳膿瘍の原因疾患として，歯科口腔感染症が最多を占めた．本検討では，脳血管疾患の既往，入院時の中等度から高度意識障害および脳室炎の合併が，転帰不良に関連する危険因子だった．これらに対して，年齢，性別，病前modified Rankin Scale（mRS），平均体温，平均白血球数やC‒reactive protein（CRP）値，膿瘍径，単発性か多発性かどうか，eloquent areaにおける局在部位，脳ヘルニアや硬膜下膿瘍合併の有無，起因菌の同定率，抗生剤治療の期間，経過中のてんかん合併の有無は転帰と関連していなかった．また，統計的に有意差はなかったが，発症後72時間未満に手術を行った早期手術群では，全症例で起因菌を分離同定する事ができた．結語として，脳膿瘍の治療において意識障害の強い例や脳室炎の合併リスクが高い例では，積極的な穿刺吸引術が検討され，入院早期から基礎疾患の管理と積極的な離床に努める事が重要である．過去の報告と比べて，本邦では歯科口腔感染症に由来する脳膿瘍が増加傾向にあり，嫌気性菌を念頭に置いたempirical antibiotic therapyが必須である．外科的排膿術を行う場合，抗生剤導入後は起因菌の検出率低下が懸念されるため，起因菌の分離同定の観点からは速やかに手術を行う事が望ましい．

82歳男性。意識障害と右片麻痺を主訴に当院へ救急搬送となった。初診時、右上下肢の間欠的痙攣、全身性の強直性痙攣が認められ、diazepamの急速静注、levetiracetamの点滴投与が行われた。しかし、投与6時間後に意識障害の遅延、痙攣の再燃がみられ、画像所見から脳膿瘍が疑われたため、抗菌薬投与が行われた。以後、第5病日のMRIで左前頭葉病変が急速に増大したため、穿頭排膿ドレナージ術を行い、培養結果から歯周病原性菌として知られるFusobacterium nucleatumが同定された。歯性脳膿瘍の診断で、治療として口腔ケアを行い、抗菌薬の投与を継続したところ、脳病変は消失、症状の改善を認め、患者は第76病日に自宅退院となった。

BACKGROUND: A common surgical approach for dominant insular lesions is to make a surgical corridor in asymptomatic cortices based on functional mapping. However, the surgical approach is difficult for posterior insular lesions in a dominant hemisphere because the posterior parts of the perisylvian cortices usually have verbal functions. OBSERVATIONS: We present the case of a 40-year-old male whose magnetic resonance images revealed the presence of contrast-enhancing lesions in the left posterior insula. Our surgical approach was to split the sylvian fissure as widely as possible, and partially resect Heschl's gyrus if the cortical mapping was negative for language tests. Because Heschl's gyrus did not have verbal functions, the gyrus was used as a surgical corridor. It was wide enough for the removal of the lesion; however, because intraoperative pathological diagnosis eliminated the possibility of brain tumors, further resection was discontinued. The tissues were histologically diagnosed as tuberculomas. Antituberculosis drugs were administered, and the residual lesions finally disappeared. According to the neurophysiological tests, the patient showed temporary impairment of auditory detection, but the low scores of these tests improved. LESSONS: The transsylvian and trans-Heschl's gyrus approach can be a novel surgical option for excising dominant posterior insular lesions.

Meningiomas are a common pathology in the central nervous system requiring complete surgical resection. However, in cases of recurrence and post-irradiation, accurate identification of tumor remnants and a dural tail under bright light remains challenging. We aimed to perform real-time intraoperative visualization of the meningioma and dural tail using a delayed-window indocyanine green (ICG) technique with microscopy. Fifteen patients with intracranial meningioma received 0.5 mg/kg ICG a few hours before observation during the surgery. We used near-infrared (NIR) fluorescence to identify the tumor location. NIR fluorescence could visualize meningiomas in 12 out of 15 cases. Near-infrared visualization during the surgery ranged from 1 to 4 h after the administration of ICG. The mean signal-to-background ratio (SBR) of the intracranial meningioma in delayed-window ICG (DWIG) was 3.3 ± 2.6. The ratio of gadolinium-enhanced T1 tumor signal to the brain (T1BR) (2.5 ± 0.9) was significantly correlated with the tumor SBR (p = 0.016). K trans , indicating blood-brain barrier permeability, was significantly correlated with tumor SBR (p < 0.0001) and T1BR (p = 0.013) on dynamic contrast-enhanced magnetic resonance imaging (MRI). DWIG demonstrated a sensitivity of 94%, specificity of 38%, positive predictive value (PPV) of 76%, and negative predictive value (NPV) of 75% for meningiomas. This is the first pilot study in which DWIG fluorescence-guided surgery was used to visualize meningioma and dural tail intraoperatively with microscopy. DWIG is comparable with second-window ICG in terms of mean SBR. Gadolinium-enhanced T1 tumor signal may predict NIR fluorescence of the intracranial meningioma. Blood-brain barrier permeability as shown by K trans on dynamic contrast-enhanced MRI can contribute to gadolinium enhancement on MRI and to ICG retention and tumor fluorescence by NIR.

BACKGROUND: Although it is known that diploic veins frequently communicate with the dural venous sinuses, the role of diploic veins in patients with venous sinus invasion from meningiomas remains unknown. METHODS: We retrospectively examined the medical records of 159 patients who underwent their first craniotomies for intracranial meningiomas. Contrast-enhanced magnetic resonance imaging was used to evaluate diploic vein routes, and digital subtraction angiography (DSA) was used to evaluate diploic vein blood flow. When high blood flow was visualized concurrently with the venous sinuses, the veins were classified as of the "early type." Diploic vein routes were classified into five routes. RESULTS: DSA was performed in 110 patients, with 14 showing superior sagittal sinus (SSS) invasion (SSS group) and 23 showing non-SSS venous sinus invasion (non-SSS group). The proportion of early type diploic veins was significantly higher in the SSS group (27.1%) than in other patients (patients without venous sinus invasion, 2.1%; non-SSS, 4.3%) (p < 0.01). In patients not in the SSS group, diploic veins were sacrificed during craniotomy in 76 patients, including four patients with veins of the early type. No patients demonstrated new neurological deficits postoperatively. In the SSS group, diploic veins were sacrificed in all patients, and early type diploic veins were cut in five patients. Two of these five patients showed postoperative neurological deficits. CONCLUSIONS: In the SSS group, diploic veins may function as collateral venous pathways, and attention is recommended for their interruption. In patients without SSS invasion, diploic veins, even of the early type, can be sacrificed.

Abstract Background: Although high dose-methotrexate therapy has been performed for primary central nervous system malignant lymphoma (PCNSL), R-MPV (rituximab, methotrexate (MTX), procarbazine and vincristine) therapy is currently the first line therapy for (PCNSL) in our hospital. This study examines the results of R-MPV therapy comparing with past treatment. Method/Subjects: Thirty-seven patients treated at our hospital from 2009 to 2020 were included. Overall survival time, progression free survival time, and toxicities were evaluated. Results: The average age of patients was 65.7 years. Patients included 21 males and 16 females. Thirty-six patients were diagnosed DLBCL by resected brain tumor tissues, and one was diagnosed DLBCL by vitreous biopsy. As initial treatment, rituximab±HD-MTX therapy (R±MTX group) was performed in 20 cases, HD-MTX therapy plus radiation (R±MTX+RT group) was performed in 12 cases, and RMPV therapy was performed in 5 cases (R-MPV group). Median OS of all cases was 69 months and median PFS was 38 months. Median OS was 69 months in R±MTX group and could not be calculated in R±MTX+RT, and R-MPV groups. Median PFS was 16 months and 56 months in R±MTX group and R±MTX+RT, respectively, and could not be calculated in the R-MPV group. Although the R-MPV group had a short follow-up period, the results were considered to be comparable to those of the R±MTX+RT group. On the other hand, grade 3/4 adverse events occurred in 50%, 25%, and 100%, respectively. Conclusion: R-MPV therapy may delay the timing of radiation and reduce the amount of radiation. On the other hand, the frequency of adverse events is high, and more strict management of treatment is required.

INTRODUCTION: One of the popular treatment strategies for complex cerebral aneurysms with wide necks or low dome-to-neck ratios is stent-assisted coiling. The most widely used intracranial stents for stent-assisted coiling are Neuroform (NF) and Enterprise (EP) stents. The purposes of this study are to review the recent literature of the past 5 years to compare outcomes between the EP and NF stent-assist coiling systems so as to comment on the safety, efficacy, complications, and recurrence rate of stent-assisted coiling in general. METHODS: PubMed was used to search for all published literature of NF or EP stent-assisted coiling of unruptured cerebral aneurysms from January 2014 to August 2019 with the search terms of "Enterprise stent-assisted coiling," "Neuroform stent," and "Neuroform vs. Enterprise stent." RESULTS: Twenty two publications met the inclusion criteria which encompass 1764 patients and 1873 aneurysms. Out of these 1873 aneurysms, 1007 aneurysms were treated with EP stent and 866 aneurysms were treated with NF stent. The overall outcome was low rates of thromboembolic complications (4.37%) and intracranial hemorrhage (1.13%), low permanent morbidity (1.70%) and mortality (0.40%), and lower rate of recanalization (11%). Data analysis shows an overall higher rate of complication and recurrence of aneurysm and lower overall rate of aneurysmal occlusion in the patients where EP stent was used in comparison to NF stent. However, this difference was not statistically significant. CONCLUSIONS: The review of two stent-assisted coiling devices using EP and NF stents including 1873 aneurysms in 1764 patients revealed that overall, it is safe and effective with comparable outcomes.

BACKGROUND: Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) provide a noninvasive window to study the neural connectivity and reconstruct the tracts. Detection of white matter injury (WMI) by DTT is a recent application being used in stroke, diffuse axonal injury, and neurodegenerative disorders. Fiber tracking in patients with brain hemorrhage can detect loss of fibers and anatomical disruption of the tracts, which can be useful in the prognostication of patient outcome. MATERIALS AND METHODS: DTI and fiber tracking was done in four patients admitted at Fujita Health University Banbuntane Hospital, Japan, with decreased consciousness following brain hemorrhage (3 patients with aneurysmal subarachnoid hemorrhage and one patient with bifrontal hemorrhage), and WMI was analyzed. We also reviewed the literature on tractography in patients with brain hemorrhage and its correlation with consciousness. RESULTS: We found significant frontal WMI in the form of thinning and anatomical disruption in all four cases. The frontal white matter tracts form an important component of the limbic system and ascending reticular activating system and frontal WMI correlated with the poor conscious level and cognitive dysfunction. Structural damage to the fiber tracts demonstrated as thinning, reduction in the volume or absence on tractography with corresponding reduction in the mean fractional anisotropy values in the frontal white matter of the affected side. CONCLUSION: DTI can be useful as a critical tool for revealing the anatomical basis for the cognitive dysfunction and unconsciousness and can be possibly used to prognosticate patient recovery. Early detection of WMI by DTI can also help in tailored rehabilitation. The authors believe that DTT could have a crucial role in the future for detecting structural changes which lead to cognitive dysfunction and further studies are needed to arrive at a specific protocol for detecting WMI.

BACKGROUND: Exact preoperative confirmation of the distal dural ring and intradural location of a paraclinoid internal carotid aneurysm has been an age old dilemma. This study was aimed at identifying anatomical landmarks in cases of paraclinoid aneurysms, which were relatively consistent, and would help in predicting the possibility of an extradural inaccessible location of these aneurysms for surgical clipping. METHODS: Ninety surgically managed unruptured paraclinoid aneurysms were retrospectively analyzed with preoperative computerized tomography. Axial relation of the aneurysm neck to the ophthalmic artery (OA), optic strut (OS), and anterior clinoid process (ACP) in terms of vertical distance and the direction of projection were analyzed and tabulated for all 90 cases. Intradural and extradural (inaccessible) aneurysms were compared. RESULTS: Seven out of the 8 inaccessible necks were medially directed and 1 was ventrally placed (P = 0.053). The OA level when compared to the neck had a positive correlation with inaccessible aneurysms for clipping (P = 0.002) The OS location above the level of the neck had significant correlation with inaccessibility of clipping and extradural location (P < 0.001). The tip of the ACP had no statistical significance with inaccessibility (P = 0.351). CONCLUSIONS: Medially projecting aneurysms with necks below the level of the OS and origin of the OA should be managed with a high index of suspicion and an alternate method of treatment should be sought. The relation of the neck to the ACP does not seem to have significant statistical bearing with decision making.

BACKGROUND: Complex middle cerebral artery (MCA) aneurysms are defined as large (≥10 mm) or giant (≥25 mm) aneurysms with M2 branches arising from the aneurysm rather than M1 segments and usually require some form of reconstruction of the bifurcation. Their management is difficult and surgery is preferred over endovascular modalities because of their peculiar angioarchitecture and association with critical branch points or perforators. OBJECTIVES: The study was aimed at analyzing surgically managed complex MCA aneurysms and discussing characteristics not favorable for endovascular management, surgical nuances and clipping strategies, patient outcomes, and newer diagnostic modalities which help improve management. METHODS: Nine cases of surgically operated complex MCA aneurysms were identified from January 2017 to July 2019. The aneurysm characteristics, surgical nuances, clipping strategies, patient outcomes and points not favoring endovascular management were tabulated and analyzed. RESULTS: The mean maximum aneurysm diameter was 13.4 mm and the mean fundus/neck ratio was 1.6. The average microscope time was 124 min, and the most common method was clip reconstruction. The average number of clips used was 2.7 and the mean follow-up was 13 months. All patients have good postoperative outcome (Modified Rankin Score 0-2). The complete occlusion rate was 88.9% with one intraoperative voluntary residual sac which was coated. Computational fluid dynamic study results done preoperatively correlated with intraoperative findings. CONCLUSIONS: MCA aneurysms pose a significant challenge for endovascular treatment because of various factors such as luminal thrombi, complex angio-architecture, precarious branch/perforator locations, broad necks, and fusiform characteristics. Surgical management in experienced hands can tackle all these problems with an armamentarium of clipping techniques and bypass procedures.