This study presents a comprehensive examination of stroke and health economics, unveiling the research endeavors in the cost-effectiveness analysis undertaken by our department. Stroke is a prominent contributor to global mortality, prompting a critical discourse on healthcare expenditures in Japan, particularly considering the aging population. Stroke management encompasses inpatient care, surgical interventions, rehabilitation programs, and preventive measures, each underpinned by distinct insurance frameworks and reimbursement modalities in the Japanese healthcare system. Numerous studies investigated stroke-related cost-efficacy concerning acute management, rehabilitation strategies, and preventive interventions, scrutinizing the efficacy and financial implications of diverse therapeutic approaches. The primary objective of our research group was to assess the cost-effectiveness of healthcare services for patients with stroke in Hokkaido, aiming at facilitating efficient healthcare resource allocation.

Background and Purpose: To clarify the clinical characteristics and outcomes for acute ischemic stroke patients during the COVID-19 era using a multi-center stroke registry in Hiroshima city. Methods: We analyzed 4111 cases of acute ischemic stroke from July 2020 to April 2023. We defined the period from July 2020 to July 2022 as the epidemic phase and the period from August 2022 onward, when the numbers of COVID-19 patients surged, as the endemic phase. Results: Compared to the epidemic phase group (n=2985), the endemic phase group (n=1126) had a significantly higher incidence of atrial fibrillation and chronic heart failure (p=0.003 and p=0.001, respectively). There was no difference in the rate of reperfusion therapy between the two groups. Although the time from discovery to hospital arrival was significantly longer in the endemic phase group (p=0.024), there was no difference in the time from hospital arrival to treatment initiation or in outcomes at 3 months. Conclusion: During the endemic phase, when the number of COVID-19 patients increased, there was an increase in ischemic strokes with atrial fibrillation and heart failure. In cases undergoing reperfusion therapy, the time from discovery to hospital arrival was significantly prolonged in the endemic phase group.

Background and Purpose: This study aimed to understand the current status of emergency stroke transport in Oita prefecture and explore solutions to identified problems. Methods: A questionnaire survey regarding suspected strokes was conducted at all fire departments in Oita prefecture. The survey covered the period from January 2021 to July 2023. Survey items included: 1) number of negotiations, 2) time elapsed for transport, and 3) number of transports by disease and medical institution. Results: The number of transports (per month) for suspected stroke was 226 in 2021, 256 in 2022, and 250 in 2023. Approximately half of these cases involved ischemic stroke, 27% involved hemorrhagic stroke, and 23% involved other pathologies. In all regions, the percentage of multiple negotiations and the time required for transport increased over time. In local areas, a higher proportion of patients were transported to nearby non-stroke hospitals than to distant stroke centers. Conclusion: In Oita prefecture, both the number of negotiations for transfers of patients with suspected stroke and the onset-to-door time have increased over time. Further investigation is needed to determine the impact of these increases on functional prognosis.

Background and Purpose: To review the treatment of an unruptured posterior communicating artery aneurysm. Methods: Fifty-five patients who underwent neurosurgical treatment (NST: 38 cases) and endovascular treatment (EVT: 17 cases) at our hospital from July 2009 to November 2023 were included. Surgical time, complications, and recurrence were compared retrospectively. Results: Surgical time was significantly different, with NST taking 209 minutes and EVT taking 135 minutes. Complications occurred in 2 NST cases and 0 EVT cases, showing no significant difference. Recurrence was observed in 0 NST cases and 3 EVT cases (with posterior communicating artery branching from the dome), with a significant difference. Conclusion: NST treatment is comparable in complications but superior in terms of recurrence. Adequate consideration of the branching of the posterior communicating artery is crucial for treatment selection.

Background and Purpose: Collateral circulation is known to influence the outcomes of mechanical thrombectomy for acute large vessel occlusion, but the assessment method has not been established. We explored the efficacy of collateral circulation assessment using simple single-phase CT angiography (CTA). Methods: From June 2015 to November 2019, we retrospectively studied 51 patients who underwent thrombectomy for ICA or MCA M1 segment occlusion. We compared the contrast-enhanced area of the occluded vessel territory on single-phase CTA to the contralateral side (collateral score 0, 0%; 1, 1–50%; 2, 51–99%; 3, 100%). The 90-day outcomes were classified as favorable for mRS grade 0–2. Results: 20 patients had favorable outcomes. No significant differences were observed between the favorable and unfavorable outcome groups in the reperfusion status and the time from onset to reperfusion. The only factor related to the outcomes was the development of collateral circulation (p=0.012). A higher collateral score was significantly associated with a higher proportion of favorable outcomes (p<0.001). Conclusion: Collateral score from single-phase CTA can easily predict the clinical outcomes of patients treated with mechanical thrombectomy, making it a convenient tool for assessing treatment indications.

Background and Purpose: Single Subcortical Infarction (SSI) sometimes shows progressive neurological deterioration despite intensive treatments. However, some patients show early improvement after deterioration. This study is aimed to identify the clinical factors associated with deterioration and early recovery from the deterioration in patients with SSI. Methods: We retrospectively analyzed the patients with SSI who were admitted to our hospital within 48 hours after the onset of stroke. The patients were classified into the progression group when their symptoms worsened as NIHSS scored≥ 2 points within 5 days of admission. In the progression group, the patients were classified into the recovery group when they recovered to the admission levels of NIHSS score within 3 days after a deterioration. We compared the clinical factors between the progression group and the non-progression group, and between the recovery group and the non-recovery group. Results: Out of 255 patients with SSI, 67 were classified into the progression group. The progression group was significantly older and had a higher rate of dyslipidemia. In the progression group, 28 were in the recovery group. The recovery group had a higher rate of using argatroban in the initial treatment. Modified Rankin Scale and functional independence measure at discharge did not differ between the recovery group and the non-recovery group. Conclusion: The use of argatroban in the initial treatment was associated with an early recovery from a deterioration in patients with SSI. However, it did not lead to favorable outcomes at discharge.

The patient was a 72-year-old man. He came to our hospital with a complaint of left wrist drop. He was suspected of having radial nerve palsy, but there was preserved synkinetic wrist extension, a phenomenon that clenching the fist leads to slight extension at the wrist. He was hospitalized due to a head MRI showing acute ischemic stroke of the right precentral knob (PK). Since lupus anticoagulant positivity was detected, he was diagnosed with antiphospholipid antibody syndrome (APS) and started on aspirin. His symptoms rapidly improved, and he was discharged on the 9th hospital day. The PK infarction would result in an inability to initiate an extension movement of the contralateral wrist and fingers, which can mimic radial nerve palsy, but the synkinetic contraction of the forearm extensors with the forearm flexors is preserved, and synkinetic wrist extension that may help in the diagnosis of the PK infarction is present. Although PK infarction is generally associated with embolic mechanisms, arterial thrombosis with APS is also a cause and should be given attention.

A 30-year-old woman was referred to our hospital for close examination and treatment of her left internal carotid artery aneurysm, which was discovered incidentally by her primary care physician. Left internal carotid artery aneurysms of wide neck were found on close examination, and the treatment policy was to provide flow diversion treatment. Aberrant right subclavian artery (ARSA) was found in the preoperative examination. Since long-term antiplatelet therapy was required, a transradial approach (TRA) was adopted. Treatment was performed in a triaxial system, and a Pipeline FLEX with Shield technology was successfully placed in the internal carotid artery to cover the aneurysm as planned. Postoperatively, MRI showed micro cerebral infarction, but it was asymptomatic. The patient was discharged home at mRS 0 with no complications at the puncture site. TRA may be an effective approach to flow diversion treatment and should be considered in patients with ARSA.

The patient is a 28-year-old female with a history of ulcerative colitis who had self-discontinued her treatment for 9 years. She presented with a sudden onset of left hemiparesis. Contrast-enhanced CT revealed an occlusion of the right common carotid artery due to a large thrombus, leading to a diagnosis of acute ischemic stroke. Emergency mechanical thrombectomy was performed; however, the thrombus was large and extensive, preventing retrieval through the guide catheter or femoral sheath, resulting in residual thrombus in the femoral artery. The contralateral femoral artery was punctured, and after completing the cerebral thrombectomy, the remaining thrombus in the femoral artery was directly retrieved using the Fogarty Maneuver, achieving successful recanalization. Chronic inflammation due to ulcerative colitis can lead to thrombocytosis and enhanced platelet function, which are considered the cause of ischemic stroke. Thrombosis associated with ulcerative colitis often forms large white thrombi predominantly composed of fibrin in large vessels, making thrombectomy technically challenging and requiring careful attention. The presence of large thrombi may require advanced techniques beyond standard catheter retrieval, including direct thrombectomy methods.

A 67-year-old male was admitted to the hospital for the treatment of bronchial asthma attacks. The patient also had takotsubo cardiomyopathy, likely caused by the frequent use of β2-agonist inhalers. No anticoagulants were administered. On the fifth day of hospitalization, the patient was found in his room with a disturbance of consciousness and was diagnosed with a stroke. At the time of diagnosis, more than 3.5 hours had passed since the patient was last known to be asymptomatic. Given the left MCA occlusion and extensive ischemic changes observed on DWI (DWI-Alberta Stroke Program Early CT Score of 4), rt-PA therapy was not administered, and mechanical thrombectomy was performed. Although aphasia persisted after rehabilitation, the patient was discharged home with an mRS score of 2. When takotsubo cardiomyopathy is suspected, it is crucial to consider the possibility of concurrent cerebral infarction during the course of treatment.

A 54-year-old woman was brought to our hospital with complaints of dysarthria and left-sided hemiparesis. MRI revealed occlusion in the distal portion of the right middle cerebral artery (M1). Thrombectomy was performed, resulting in successful recanalization. During the thrombectomy, a carotid web (CaW) was observed on the posterior wall of the right internal carotid bulb. Postoperative examinations confirmed the absence of other embolic sources, leading to the diagnosis of embolic stroke caused by a CaW. Fourteen days after the onset, carotid endarterectomy was performed as curative revascularization and a favorable outcome was achieved. The retrieved mixed thrombus, primarily composed of fibrin, suggested that platelet aggregation, in addition to blood flow stagnation at the lesion site, may be involved in clot formation in CaWs. This case highlights the importance of considering a CaW in the differential diagnosis and performing a thorough examination of the carotid arteries in patients with embolic stroke of undetermined source and no apparent stroke risk factors.

A 41-year-old woman with a history of heavy-ion therapy 19 years prior for paranasal sinus osteosarcoma was admitted to our hospital due to persistent rhinorrhagia. On Day 3 of hospitalization, the patient developed rebleeding. The bleeding likely originated from the sphenopalatine artery territory, and embolization of the distal right maxillary artery was performed on the same day. On Day 4, a massive rhinorrhagia caused sudden cardiac arrest; however, the patient was successfully resuscitated. On Day 5, the patient underwent right external carotid artery ligation for effective hemostasis. Despite this, active rebleeding occurred on Day 8. On Day 10, she was referred to our department with a strong clinical suspicion of hemorrhage in the right internal carotid artery (ICA). Emergency digital subtraction angiography revealed a pseudoaneurysm involving the C3 segment of the right ICA, with adequate collateral circulation. We performed a parent artery occlusion of the right ICA, including the aneurysm. The patient recovered well postoperatively, without recurrent rhinorrhagia or neurological deficits. Rhinorrhagia caused by a pseudoaneurysm of the ICA can be fatal shortly after its onset. In patients with a history of radiation therapy, a pseudoaneurysm of the ICA should be considered a possible contributing factor. Careful investigation to identify the bleeding source and prompt medical treatment are important.