BACKGROUND: While the efficacy of statins, which are cholesterol-lowering agents, in preventing subarachnoid hemorrhage (SAH) has been examined in experimental animal models and some clinical studies, findings remain inconclusive. This study aimed to investigate the association between statin use and the risk of SAH. METHODS: We conducted a large population-based case-control study using data from the Japanese Health Insurance Claims Database from January 2005 to August 2021. This nationwide database includes the data of individuals aged 0 to 74 years. Cases were defined as patients hospitalized with a first diagnosis of SAH ( International Classification of Diseases, Tenth Revision code I60) during this period. Four controls per case were randomly selected and matched by age, sex, and follow-up period using incidence density sampling. Statin exposure (use, recency, and duration) was evaluated before the incidence of SAH. Conditional logistic regression, adjusted for patient characteristics, was used to assess the association between statin use and SAH risk. We also investigated whether this association varies with a history of hypertension, diabetes, cerebrovascular disease, unruptured intracranial aneurysms, and the use of antihypertensive medications. RESULTS: The study identified 3498 cases and 13 992 matched controls. Statin use was reported in 12.2% of SAH cases and 12.7% of the controls. After adjusting for patient characteristics, statin use was associated with a significantly reduced risk of SAH (adjusted odds ratio, 0.81 [95% CI, 0.69–0.95]). The association was significantly influenced by a history of hypertension or cerebrovascular disease ( P _interaction =0.042 and 0.042, respectively). CONCLUSIONS: Statin use was significantly associated with a reduced risk of SAH. These findings suggest that statins may play a role in the prevention of SAH, particularly in patients with a history of hypertension or cerebrovascular disease.

Indocyanine green (ICG) is a cyanine dye useful for visualizing blood vessels; it has been developed for endoscopy and is used in skull base surgery. Endoscopy is widely used for hematoma removal after an intracerebral hemorrhage since it is minimally invasive and has a shorter operation time than craniotomy. However, with this technique the surgical field is limited and it is difficult to obtain an adequate orientation; thus, it is challenging to locate the bleeding point, and postoperative rebleeding has been reported. We performed intraoperative ICG near-infrared fluorescence imaging to locate the bleeding point. This purpose of this study was to evaluate the usefulness of ICG angiography during endoscopic hematoma removal in two patients, using two endoscope types and comparing their visualization of perforating branches during the procedure. ICG angiography was performed in two different cases of putaminal hemorrhage, using the SPIES NIR/ICG-System and IMAGE1 S Rubina (both KARL STORZ, Tuttlingen, Germany) at the intraoperative bleeding site. The intraoperative use of ICG allowed the clear visualization of the perforating branches and real-time confirmation of active bleeding. We could also distinguish an old hematoma from the active bleeding point. The IMAGE1 S Rubina has adequate brightness for contrast enhancement, allowing surgical manipulation simultaneously to the enhancement phase.ICG fluorescence angiography is useful to identify the damaged vessel and perform hemostasis. We expect other similar devices to be developed in the future, accompanied by flexible and thin rigid endoscopes.

(1) Background Cerebral revascularization is necessary to treat intracranial arterial stenosis caused by moyamoya disease, atherosclerosis, or large complex aneurysms. Although various donor vascular harvesting methods have been reported safe, there are no reports on the histological evaluation of donor vessels for each disease, despite the variety of diseases wherein vascular anastomosis is required. (2) Methods Pathological findings of the superficial temporal artery (STA), radial artery (RA), occipital artery (OA), and saphenous vein (SV) harvested at the institution were analyzed. Patients classified according to aneurysm, atherosclerosis, and moyamoya disease were assessed for pathological abnormalities, medical history, age, sex, smoking, and postoperative anastomosis patency. (3) Results There were 38 cases of atherosclerosis, 15 cases of moyamoya disease, and 30 cases of aneurysm in 98 donor vessels (mean age 57.2) taken after 2006. Of the 84 STA, 11 RA, 2 OA, and 1 SV arteries that were harvested, 71.4% had atherosclerosis, 11.2% had dissection, and 10.2% had inflammation. There was no significant difference in the proportion of pathological findings according to the disease. A history of hypertension is associated with atherosclerosis in donor vessels. (4) Conclusions This is the first study to histologically evaluate the pathological findings of donor vessels according to disease. The proportion of dissection findings indicative of vascular damage due to surgical manipulation was not statistically different between the different conditions.

With the development of stereotactic radiotherapy, opportunities to perform craniotomies for brain tumors under a microscope are decreasing, making it difficult to learn surgical techniques in clinical practice. For safety and ethical reasons, it is useful to create a brain tumor training model for hands-on practice. We created a sphenoidal ridge meningioma model with the following parameters: (1) the location of the tumor should be distinguishable using neuronavigation, (2) the feeding artery should allow for confirmation and hemostasis, (3) the tumor and brain should be properly adherent and dissectable, and (4) the tumor can be decompressed and removed using an ultrasonic surgical device. We created the model out of polyvinyl alcohol and produced a mold using a 3-dimensional printer. Thirteen young neurosurgeons used these models, and a questionnaire survey was conducted. It was possible to train neurosurgeons for tumor removal using this model. The results of the questionnaire showed that the model, usefulness of the clinical application, and willingness to participate again were highly rated. This model was created to practice procedures with realty and designed to be visualized by navigation systems, to be removed with ultrasonic surgical instruments, and to be dissected using microinstruments. This model is useful to learn surgical techniques and strategies and to test and develop new surgical equipment. Training using a brain tumor model should be good off-the-job training for young neurosurgeons.

Microscopic surgery poses ergonomic challenges due to the constraints of fixed eyepieces. While monitor-based exoscopes offer alternatives, they may limit immersion and assistant visibility. Head-mounted displays (HMDs) have proposed these constraints. This study evaluated the technical capabilities of a three-dimensional high-definition HMD system during surgical simulation to determine its usability compared with conventional and exoscopic visualization methods. Thirty-five physicians and residents with varying microsurgical experience evaluated 3 visualization methods: HMD, conventional microscope eyepieces, and a 55″ exoscopic monitor. The evaluation criteria included resolution, immersion, depth perception, ergonomic comfort, peripheral vision, and visual latency. We also measured the effective latency times. HMD ranked between the microscope and exoscope across all evaluation criteria. The microscope was rated highest in resolution, immersion, depth perception, and visual latency. Surgeons with >5 years of practice rated HMD higher than microscopes for ergonomics (P = 0.029) and peripheral vision (P = 0.009). The measured image latency was approximately 0.093 ± 0.0018 s. Finally, the HMD system showed better operator and assistant participation. While the HMD showed potential for ergonomic benefit and enhanced peripheral engagement, further development is needed, particularly regarding image quality, and magnification. Given that clinical integration in this preliminary study was limited to observation; further development is needed, including larger numbers of cases and diverse operative settings, including primary surgeons, assistants, scrub nurses, and surgical observers.