Published papers

We evaluated long-term outcomes in patients treated with carotid endarterectomy (CEA). Postoperative intima-media thickness (IMT) and peak systolic velocity (PSV) were measured using duplex ultrasonography in 38 patients. In addition, the long-term survival of the patients after CEA was assessed. The mean follow-up period was 60 months. The IMT was increased in 15 patients, and changing patterns were categorized into the three following groups: gradual increase, transient peak, and plateau. Postoperative uncontrolled diabetes mellitus (defined as HbA1c level of >7.0) was the only predictor of increased IMT of ≥2 mm. Restenosis (defined as >50% stenosis or >150 cm/s of PSV) or occlusion of the internal carotid artery occurred in 2 patients (5%). In the present case with restenosis, spontaneous restoration was observed after hospitalization without smoking habit for 6 months. Other diseases that required treatment were found in 18 patients (47%) despite routine preoperative systemic examination such as blood examination and chest X-ray photography, and evaluation of current ischemic coronary disease. Of the 18 patients, 6 had cancer and 7 had cardiovascular events. One patient died because of pancreatic cancer, and another patient with acute subdural hematoma had a decrease in modified Rankin scale score. These results indicate that careful postoperative follow-up of IMT and systemic surveillance may play a key role to achieve favorable long-term out-come after CEA.

We report the clinical features of six patients who underwent direct surgery at our hospital for large or giant cervical internal carotid artery aneurysms (CICAAs). Three patients underwent aneurysm resection with end-to-end anastomosis of the internal carotid artery (ICA), and three patients underwent proximal occlusion of the ICA. Five patients had good outcomes, including one case with transient dysphagia. In one case, a middle cerebral artery embolization occurred due to ICA occlusion, and the patient died due to extensive cerebral infarction. To avoid ischemic complications in direct surgery for CICAA, preoperative cerebral blood flow assessment and perioperative antithrombotic therapy are indispensable. In addition, to avoid lower cranial nerve palsy during dissection of the aneurysm from surrounding structures, a bloodless surgical field; safe, reliable internal shunt insertion and vascular suture techniques; and an accurate understanding of the anatomy of the neck are also necessary.

当院で頸部頸動脈瘤に対し直達術を行った6例(男性1例、女性5例、平均年齢56.7歳)について検討した。その結果、全例が症候性内頸動脈瘤であり、瘤径は平均35.8mm、動脈瘤内血栓化を2例に認められた。手術法は3例で動脈瘤の切除と内頸動脈の端々吻合による血行再建が行われ、残る3例で母血管閉塞が行われていた。動脈瘤を切除した3例の病理所見はいずれも動脈硬化性動脈瘤であった。5例が転帰良好であったが、1例は内頸動脈閉塞から中大脳動脈塞栓を生じ、広範な脳梗塞により死亡していた。

To clarify the optimal timing of surgical or endovascular treatment for patients with small-sized (<5 mm) unruptured intracranial aneurysms (UIA) with conventional follow-up, we retrospectively evaluated the characteristics of UIA that ruptured or enlarged during observation. From 1999 to 2014, 316 UIA (271 cases) were initially treated without surgical or endovascular intervention. Four ruptured and 17 grown UIAs were treated with clipping or coil embolization. In these cases, the ratio of the internal carotid to the posterior communicating artery and that of the anterior cerebral artery to the anterior communicating artery was 71%. Intraoperative findings revealed that the bleb formed during follow-up was observed as a very thin wall. Ruptured UIAs are prone to rapid growth. We conclude that location, growth rate, and bleb formation are useful to estimate the risk of rupture of smallsized UIAs during follow-up.

発見時の最大径が5mm未満で、経過観察となった未破裂脳動脈瘤316瘤を対象に、治療介入を決定する因子と的確な介入時期について検討した。その結果、1)本検討では局在(a-com、IC-PC)に加え、速い年間増大速度と形状変化(blebあるいは細長い変形)を伴う増大は破裂の危険が高く、迅速に治療介入を行う必要があると考えられた。2)治療介入時期を逃さないためには、2回目の検査は3ヵ月以内に実施し、その後も半年ごとの定期検査を2年間は継続する必要があると考えられた。

CPAではNH3が高値を呈することが明らかとなった.このNH3上昇には代謝性アシドーシスが関与することが示された

This study aimed to validate the hypothesis that the ratio of cerebral blood flow (CBF) at rest in the lenticular nucleus (LN) territory to that in the middle cerebral artery (MCA) territory is higher in symptomatic Moyamoya disease (MMD) patients than in asymptomatic MMD patients. This was a retrospective observational study of adult patients with documented MMD who underwent single-photon emission computed tomography (SPECT) and had been examined at the Department of Neurosurgery of Keio University Hospital during a 10-year period (2006–2016). The diagnosis was made on the basis of typical imaging findings. We classified unoperated MMD patients into three groups: class I, no evidence of stenosis or occlusion hemispheres and without symptoms in unilateral MMD patients; class II, hemispheres with stenosis or occlusion but without ischemic symptoms; and class III, hemispheres with evidence of stenosis or occlusion associated with ischemic symptoms. Hemodynamic stress distribution (hdSD) was defined as the ratio of CBF in one LN to the CBF in the peripheral MCA; this was obtained by SPECT at rest. We compared the values of CBF and hdSD among the groups. A total of 173 adult patients were diagnosed with MMD from January 1, 2006, to January 1, 2016. Among them, 85 MMD patients underwent SPECT studies. After excluding inappropriate cases, 144 hemispheres were included in our analysis. hdSD was significantly higher (p < 0.001) in hemispheres with ischemic symptoms (class III, mean hdSD = 1.1; 36 sides) than in those without symptoms (class II, mean hdSD = 1.03; 82 sides). However, CBF at rest in the MCA or LN was not significantly associated with ischemic symptoms. The optimal threshold for hdSD to have ischemic symptoms was 1.040 (area under the curve; 74% sensitivity 91.7% and specificity 54.9%). We used SPECT to investigate cerebral blood from MMD patients and found that high hdSD values were predictive of ischemic symptom development in these patients.

開頭手術と血管内複合治療(術中血管撮影を含む)を行った脳血管障害の症例を、手術台と血管撮影装置を兼ね備えたhybrid operating room(HOR)導入前後で比較し、HORの有用性について検討した。血管内治療医と共同で複合治療を行った脳血管障害の患者17例(男性10例、女性7例、平均49歳)を対象に、HOR導入前の前期11例、導入以後の後期6例に分類した。前期の11例中、部屋を移動して血管内治療を行ったのは4例であった。後期の6例はいずれも問題なく治療が終了した。転帰は原疾患の重症度が理由でsevere disabilityとなった症例を除き、全例でgood recoveryであったが、術後のminor strokeによる軽度顔面神経麻痺を1例に認めた。複雑な脳血管病変に対する開頭手術と血管内治療の複合治療は、HORを使用することで、より安全かつ円滑に完遂させることが可能であった。

Here we investigated the changes in utility and limits of combined microsurgical and endovascular treatment for complex cerebrovascular disease before and after the introduction of the hybrid operating room (HOR) in our department. Since 2006, a total of 17 patients (cerebral aneurysm in 12, cerebral arteriovenous malformation in 5) underwent integrated microsurgery with endovascular treatment. In 3 of 11 patients treated before the introduction of HOR, certain problems such as time consumption during patient transfer, disconnected workflow, and complicated operation due to poor quality of support equipment occurred. In contrast, all 6 operations in the HOR were uncomplicated. All therapeutic steps including anesthesia management were planned in a single session. In conclusion, HOR provides a safe and smooth workflow in combined microsurgical and endovascular treatment for complex cerebrovascular diseases.

Purpose: The venous plexus of Rektorzik (VPR), first described by Rektorzik in 1858, is a venous plexus around the internal carotid artery in the carotid canal. However, the VPR has never been investigated using the recently developed imaging modalities. In this study, we analyzed the VPR using computed tomography-digital subtraction venography (CT-DSV). Methods: This study included 253 patients who had undergone head CT-DSV. The presence or absence of the right and left VPRs and their connecting veins were visually examined by two researchers. Results: The VPR was observed in 60 patients (24%), 39 of which showed VPR only on the right side, 10 only on the left side, and 11 on both sides. VPR was significantly more common on the right side (p = 0.0002) and was observed more frequently around the horizontal segment of the internal carotid artery than around the vertical segment. The most common veins identified as distal and proximal VPR connections were the cavernous sinus (63/71, 89%) and the anterior condylar confluence (27/71, 38%), respectively. The mean age was significantly lower in patients with the VPR than in those without (53 vs. 57 years, p = 0.02). Conclusion: The VPR was significantly more frequent on the right side and in younger patients but was not a radiographically constant structure. In most cases, the VPR connected the cavernous sinus and anterior condylar confluence. Preoperative evaluation of VPR may lead to refined surgical procedures.

In this study, we developed and validated the Clinical Student Version of the Japanese Interprofessional Competency Self-Assessment Scale (C-JASSIC) for healthcare students in their clinical practice phase. Data obtained from 331 students (medical, 98; nursing, 99; pharmacy, 134) during orientation for interprofessional education (pre-IPE) and from 319 students (medical, 94; nursing, 93; pharmacy, 132) within a week following IPE (post-IPE) were analyzed. Exploratory pre-IPE and Confirmatory post-IPE factor analyses revealed a consistent 6-factor structure aligning with the Japanese Interprofessional Competency domains. The scale exhibited strong internal consistency, with Cronbach’s α values exceeding 0.8 for all factors both pre- and post-IPE. Scores for overall competency and individual domains increased post-IPE in 234 matched cases. A notable significant pre vs post difference concerned “Understanding of Others,” indicating enhanced interprofessional comprehension after clinical practice. There was a weak but significant positive correlation between IPE satisfaction and difference in pre- and post-IPE scores. However, no significant differences were observed among medical, nursing, and pharmacy students. Despite its strengths, such as its competency-based design and cultural relevance to Japan, a limitation of the study may be potential self-reporting bias. Nonetheless, C-JASSIC represents a valuable tool for seamless competency evaluations from student to professional stages, with implications for broader Asian contexts.

Background: There are many scores and markers that predict poor outcome in patients with subarachnoid hemorrhage (SAH). However, parameters that can predict outcomes in patients with SAH with high specificity and sensitivity, which can be identified in the early postictal state and utilized as a clinical marker of early brain injury (EBI) have not been identified so far. Methods: Thirty-nine patients with SAH due to a saccular intracranial aneurysm rupture were reviewed. We retrospectively analyzed the relationships between patients' baseline characteristics and patients' outcomes to identify parameters that could predict patient outcomes in the early postictal state. Results: In the univariate analysis, older age (>65), loss of consciousness (LOC) at ictus, poor initial World Federation of Neurosurgical Societies (WFNS) grade (3-5), and delayed cerebral ischemia (DCI) were associated with poor outcome (GOS 1-3). Statistical analyses revealed that combined LOC at ictus and/or poor initial WFNS grade (3-5) was a more powerful surrogate marker of outcome (OR 15.2 [95% CI 3.1-75.5]) than either LOC at ictus or the poor initial WFNS grade (3-5) alone. Multivariate logistic regression analyses revealed that older age, combined LOC at ictus and/or poor initial WFNS grade, and DCI were independently associated with poor outcome. Conclusion: Combined LOC at ictus and/or poor initial WFNS grade (3-5) reflects the impact of EBI and was a useful surrogate marker of poor prognosis in SAH patients, independent of patients' age and state of DCI.

We report a case of subarachnoid hemorrhage due to a rupture of an aneurysm at the right internal carotid artery-posterior communicating artery in a patient with Marfan syndrome. Since the patient had a history of aortic dissection that was treated conservatively, we selected clipping rather than coil embolization as the surgical strategy for the patient. She was surgically treated successfully, and discharged from our hospital without neurological sequelae 18 days postoperatively. From the findings of the present case in combination with a review of the literature, cerebral aneurysms in patients with Marfan syndrome may be developed due to the fragility of elastic membranes of major cerebral arteries, and we emphasize the importance of developing surgical strategy based on the fragility of elastic membranes.

60歳代女性。Marfan症候群の既往に有する。今回、突然の激しい頭痛を主訴に近医を受診、CT所見でくも膜下出血を指摘され、治療目的で著者らの施設へ救急搬送となった。3D-CTA所見より右内頸動脈-後交通動脈分岐部の動脈瘤破裂と診断され、緊急で開頭クリッピング術を施行されることとなった。だが、全身麻酔、手術に先立ち、腰椎ドレナージの留置を検討したところ、Marfan症候群による脊椎の側彎が強く、正中確認が困難であった。そこで、術前3D-CTAから想定された動脈瘤は小さく、形状から解離も考えられたため、脆弱である可能性を念頭に、エダラボン点滴の上、右頭蓋内内頸動脈近位部を注意深くtemporary clipにて遮断し、瘤内の圧力を減じてから後交通動脈および近位側ネックを確認後、クリッピングした。その結果、術後経過は良好で、患者は後遺症なく第18病日目に独歩退院となった。尚、術後3ヵ月経過でのmRSは0で、動脈瘤の再発はみられていない。