In a mechanical thrombectomy for acute major cerebral artery occlusion, it is important to shorten the time from the patient’s arrival to the puncture (i.e., the door‒to‒puncture [D2P] time). Perfusion imaging and a mismatch analysis using fully automated (rapid processing of perfusion and diffusion [RAPID]) cerebral perfusion imaging software were introduced at our institution, and there was concern that the D2P time would be extended because more time is required for the RAPID software’s image acquisition. We compared the impact of using the RAPID program on the D2P time. The subjects were 125 consecutive patients who underwent a mechanical thrombectomy for an acute ischemic infarction with cerebral artery occlusion during the period August 2018 to January 2023. There were 56 patients in the pre‒RAPID group and 69 patients in the post‒RAPID group, and 65 (94%) of the post‒RAPID patients underwent CT perfusion or MRI perfusion. The median D2P time (IQR) was 74 (61‒93) min in the post‒RAPID group, which was 15 min shorter than the 89 (66‒102) min in the post‒RAPID group (p＜0.05). Shortening of the D2P time is believed to contribute to the clinical outcomes of mechanical thrombectomy for acute cerebral artery occlusion, and although there was concern that the use of the RAPID software would extend the D2P time, the present results demonstrated that the D2P time was shortened after the introduction of RAPID. A possible reason for the shortened D2P time is that the introduction of RAPID software enabled early diagnoses, early indication judgments, and the visualization of treatment goals, as did our implementation of measures to shorten the D2P time such as reviewing the stroke hotline system and the hospital system. The RAPID software may thus be useful for shortening the D2P time.

  We describe a successful collaboration between two public acute care hospitals in Japan’s Shiga prefecture: Otsu City Hospital and Saiseikai Shiga Hospital. These hospitals are situated in different medical areas, and each is responsible for secondary and tertiary emergency care. Leveraging their geographical proximity and staff interactions, the two hospitals developed a coordinated system to enhance their neurosurgical and neurological emergency care capabilities. This collaboration was achieved through the use of social networking service (SNS) tools, enabling real‒time communication and data‒sharing between neurosurgeons and neurologists at the two institutions. The coordinated system is designed to streamline the treatment process for patients with urgent needs, particularly those with critical neurological conditions. After implementing the collaborative system in 2022, Otsu City Hospital handled approx. 1,080 neurological emergency patients annually, with 224 of these patients requiring hospitalization; in addition, 29 emergency cases were transferred to Saiseikai Shiga Hospital. Among these transfers, 10 were categorized as ultra‒urgent cases, including critical conditions such as main cerebral artery occlusion and impending cerebral hernia. Among these 10 cases, seven patients with main cerebral artery occlusion underwent a mechanical thrombectomy. The average time from the contact with a consultant to the initiation of treatment for these 10 patients was 103.4 ± 44.7 min, with six patients (67%) achieving effective reperfusion with Thrombolysis in Cerebral Infarction (TICI) scores ≥ 2 points. Our comparison of the pre‒system implementation data from Otsu City Hospital (in which six mechanical thrombectomies were performed over a 3‒year period) identified no significant difference in the waiting time for diagnosis and treatment, with an average of 101.1 ± 27.8 min. In today’s highly specialized medical landscape, collaboration between acute‒care institutions with different characteristics presents an opportunity to complement weaknesses and leverage strengths. However, examples of close cooperation between two acute‒care hospitals in the field of neurological emergency care are scarce. The present system, which established a highly effective and close inter‒hospital collaboration for neurological emergency cases through the use of SNS groups among staff, demonstrates the potential of such approaches to contribute to regional healthcare improvement.

  The most important issue in mechanical thrombectomy is to shorten the time from stroke onset to recanalization. At our stroke center (which opened in January 2021), we have achieved a certain level of success in reducing the time from hospital arrival to recanalization by improving the hospital environment. However, there has been a noticeable delay between patients’ visits to a previous hospital and their arrival at our hospital, and there have been cases in which a cerebral infarction had occurred by the time of the patient’s arrival and other cases in which an extensive cerebral infarction occurred despite rapid recanalization. We thus investigated the use of physicians’ own vehicles (driven by the physicians) for transferring patients from other facilities to our hospital, and the associated problems. The study included patients who were transferred to our hospital for acute stroke treatment during the period from January 2021 to December 2022 via a physician’s vehicle (n=22) or an ambulance (n=18), and we obtained the patients’ mechanical thrombectomy data after their transfer to our hospital. No significant difference was detected between the transportation capability of the ambulances and the physicians’ vehicles. The time required to collect the patients from the referring hospital was also not significantly different between the two modes of transfer. However, our analyses revealed that the process could be shortened with some ingenuity. The physicians’ vehicles had the advantage of saving steps after a patient’s arrival by providing treatment to the patient and/or explanations to their family members during the transfer, but dispatching physicians’ vehicles to distant hospitals (i.e., >6 km away from our hospital) did not reduce the total time to recanalization. Our results suggest that transferring patients for mechanical thrombectomy via physicians’ vehicles can help save time if the conditions are set according to each medical region.

  A rapid response system (RRS) was introduced at our stroke center to intervene in the care of patients with unexpected clinical deterioration, together with a rapid response team (RRT) consisting of physicians and nurses who respond to the RRS. We evaluated the performance of our RRT and assessed the impact of the RRS on patient outcomes. Sixty RRT activations occurred during the study period. The 60 activations were performed in the stroke intensive‒care unit (35.0%), stroke high‒care unit (48.3%), and others (general wards, laboratory departments, etc.) (16.7%). Most of the RRT activations took place during the day shift, and 93.0% of the activations were for “full code,” which indicates that the patient consented to full resuscitation measures. The most frequent reason for RRT activation was respiratory failure (60.0%), followed by arrhythmia (11.7%) and hypotension (10.0%). The median National Early Warning Score (NEWS) was 9 (interquartile range 7‒12). Of the patients who required the RRT, 46.7% were discharged due to death, and 67.9% of the causes of death were unrelated to the primary diagnosis. A comparison of the alive and dead groups revealed that a Glasgow Coma Scale score 13‒15 (25.8% vs. 0%, P=0.006) and a low/moderate risk NEWS, i.e., 0‒6 (34.4% vs. 3.6%, P=0.003) were predictors of clinical outcomes. Early activation of a rapid response team is essential to optimize the effectiveness of an RRS.

  We report a case of bilateral acute subdural hematoma caused by a ruptured right internal carotid artery and posterior communicating artery aneurysm. The patient, a 66‒year‒old Japanese man, presented to our hospital with the complaint of a severe headache that began the day before his arrival. CT and MRI showed bilateral acute subdural hematomas without subarachnoid hemorrhage, and MRA revealed a right internal carotid and posterior communicating artery aneurysm, which was investigated by computed tomography angiography (CTA) and digital subtraction angiography (DSA). A lumbar puncture was performed and no bleeding was detected, but contrast‒enhanced MRI showed a contrast effect on the bleb of the aneurysmal wall, which led us to conclude that the aneurysm was unstable. Surgery was scheduled; the patient exhibited a rapid decline in consciousness before the surgery and the hematoma was enlarged, and thus clipping surgery was performed urgently. Although extremely rare, bilateral acute subdural hematomas without bilateral hemorrhage can be caused by ruptured aneurysms even in the absence of hemorrhage on a lumbar puncture, thus requiring close examination and prompt treatment as in cases of ruptured cerebral aneurysms.

  We report a ruptured dissecting internal carotid aneurysm caused by epistaxis.

  A 92‒year‒old Japanese woman who had epistaxis was brought to our hospital as an emergency. Contrast‒enhanced computed tomography and MRI showed fluid filling in the left sphenoid sinus and an irregular aneurysm protruding into the left sphenoid sinus. We suspected that an internal carotid artery (ICA) aneurysm was ruptured. Because her epistaxis was under control, the patient underwent coil embolization the next day. However, she had epistaxis again on postoperative days 7 and 14. Because the epistaxis 14 days postsurgery was accompanied by hypotension, coil embolization was performed again. Cerebral angiography revealed a new aneurysm at a site other than the initial coil embolization, accompanied by a bleb. Another coil embolization with a stent was conducted, and the patient was admitted to the institution doing well. However, about 1 month after the treatment, she developed a subarachnoid hemorrhage (SAH) while hospitalized for heart failure and passed away. There are very few reports of a ruptured ICA aneurysm with epistaxis, and this condition is said to be related to a history of head trauma. Recurrence of epistaxis may be due to further intracranial extension of the dissection beyond the region of the coil embolization. There are several options for treatment, and the patient’s age and general condition must be considered for all options.

  Our hospital has introduced a hybrid emergency room system (HERS) to shorten the time from the arrival of patients with a head injury to diagnostic imaging. The HERS is also used to achieve rapid decompression effects by allowing perforation to be performed at the same location. We describe the cases of three consecutive patients who were treated after the introduction of the HERS. We observed an improvement in the pupillary findings of two of the patients by performing perforation before a craniotomy was conducted in the operating suite. The introduction of a HERS can be expected to shorten the imaging examination time and to provide an emergency decompression effect by enabling the performance of perforation. Cases such as those described herein indicate that a HERS may be useful in the treatment of severe acute subdural hematoma.