Search

Background: Long-term outcomes are unknown in patients with asymptomatic moyamoya disease. In this report, we aimed to clarify their 5-year risk of stroke and its predictors. Methods: We are conducting a multicenter, prospective cohort study (Asymptomatic Moyamoya Registry) in Japan. Participants were eligible if they were 20 to 70 years, had bilateral or unilateral moyamoya disease, experienced no episodes suggestive of TIA and stroke; and were functionally independent (modified Rankin Scale score 0–1). Demographic and radiological information was collected at enrollment. In this study, they are still followed up for 10 years. In this interim analysis, we defined the primary end point as a stroke occurring during a 5-year follow-up period. Independent predictors for stroke were also determined, using a stratification analysis method. Results: Between 2012 and 2015, we enrolled 109 patients, of whom 103 patients with 182 involved hemispheres completed the 5-year follow-up. According to the findings on DSA and MRA, 143 hemispheres were judged as moyamoya disease and 39 hemispheres as questionable manifestations (isolated middle cerebral artery stenosis). The patients with questionable hemispheres were significantly older, more often male, and more frequently had hypertension than those with moyamoya hemisphere. Moyamoya hemispheres developed 7 strokes, including 6 hemorrhagic and 1 ischemic stroke, during the first 5 years. The annual risk of stroke was 1.4% per person, 0.8% per hemisphere, and 1.0% per moyamoya hemisphere. Independent predictor for stroke was Grade-2 choroidal anastomosis (hazard ratio, 5.05 [95% CI, 1.24–20.6]; P =0.023). Furthermore, microbleeds (hazard ratio, 4.89 [95% CI, 1.13-21.3]; P =0.0342) and Grade-2 choroidal anastomosis (hazard ratio, 7.05 [95% CI, 1.62–30.7]; P =0.0093) significantly predicted hemorrhagic stroke. No questionable hemispheres developed any stroke. Conclusions: The hemispheres with asymptomatic moyamoya disease may carry a 1.0% annual risk of stroke during the first 5 years, the majority of which are hemorrhagic stroke. Grade-2 choroidal anastomosis may predict stroke, and the microbleeds and Grade-2 choroidal anastomosis may carry the risk for hemorrhagic stroke. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: UMIN000006640.

OBJECTIVE Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by progressive stenosis of the internal carotid artery (ICA) and secondary formation of collateral vessels. Revascularization surgery is performed in patients with MMD to prevent stroke; however, the pathogenesis of MMD remains unknown. Recently, long noncoding RNAs (lncRNAs) have been found to play a key role in gene regulation and are implicated in various vascular diseases. However, the lncRNA expression profile in MMD lesions has not been investigated. In this study the authors aimed to determine the characteristics of lncRNA expression in MMD lesions. METHODS The authors collected microsamples of the middle cerebral artery (MCA) from patients with MMD (n = 21) and patients with control conditions (n = 11) who underwent neurosurgical treatment. Using microarray experiments, the authors compared the profiles of lncRNA expression in the MCAs of the MMD and control patient groups and identified differentially expressed lncRNAs (fold change > 2, q < 0.05). In addition, the neighboring coding genes, whose transcription can be regulated in cis by the identified differentially expressed lncRNAs, were investigated and Gene Ontology (GO) analysis was applied to predict associated biological functions. RESULTS The authors detected 308 differentially expressed lncRNAs (fold change > 2, q < 0.05), including 306 upregulated and 2 downregulated lncRNAs in the MCA from patients with MMD. Regarding the prediction of biological function, GO analyses with possible coding genes whose transcription was regulated in cis by the identified differentially expressed lncRNAs suggested involvement in the antibacterial humoral response, T-cell receptor signaling pathway, positive regulation of cytokine production, and branching involved in blood vessel morphogenesis. CONCLUSIONS The profile of lncRNA expression in MMD lesions was different from that in the normal cerebral artery, and differentially expressed lncRNAs were identified. This study provides new insights into the pathophysiology of MMD.

Purpose: Recently, the importance of molecular diagnosis has increased, along with the volume of specimens required for diagnosis. Biopsy procedures must simultaneously reduce invasiveness and ensure the collection of adequate tissue volume. We examined the efficacy and safety of endoscopic biopsy using a minimal diameter cylinder.Methods: Patients who underwent endoscopic biopsy surgery with a 6-mm diameter cylinder for intraparenchymal lesions were included. Postoperative hematoma formation and the extent of trajectory scarring were assessed. Molecular genetic analysis was performed for cases of diffuse infiltrated glioma.Results: Fifty-two procedures performed on 51 patients were analyzed in this study. Postoperative neurological deterioration was not observed in any case. A pathological diagnosis was made for all patients. Postoperative CT revealed no hematoma after 49 procedures and a small hematoma after 3 procedures, and no patients required additional treatment. A postoperative trajectory scar less than 5 mm in size was observed after 30 procedures, a scar of 5-10 mm was observed after 19 procedures, and a scar larger than 10 mm was observed after 3 procedures at 1 week after surgery, and 40, 6 and 0 scars were observed at 3 months after surgery. Molecular genetic analysis was performed in 17 cases, resulting in a change to a higher grade in the integrated diagnosis of 3 cases.Conclusions: Endoscopic biopsy using a small-diameter cylinder is a possible alternative biopsy technique for intraparenchymal lesions. This surgical technique is useful especially in cases where hemorrhagic complications are expected.Trial registrationRegistry name and number: Efficacy and safety of the neuro-endoscopic treatment for brain tumors. (2019-0254)

Cerebral cavernous malformations (CMs) presenting with focal neurological symptoms or mass effects require surgical removal. In recent years, cylindrical retractors have been widely utilized for the removal of deep-seated lesions during both microscopic and endoscopic surgery. In the present study, we evaluated the efficacy and safety of endoscopic transcylinder removal of CMs using a novel wet-field technique.We included 13 patients with supratentorial CMs who had undergone endoscopic transcylinder surgery between April 2013 and March 2022. One patient experienced recurrence of the CM and underwent a second endoscopic transcylinder surgery. Therefore, we retrospectively evaluated 14 procedures. The surgical field was continuously irrigated with artificial cerebrospinal fluid to maintain expansion and visualization of the tumor bed. We termed this method as the "wet-field technique." Patient characteristics, symptoms, and pre- and postoperative magnetic resonance imaging results were obtained from medical records.The average maximum CM diameter was 35.3 mm (range: 10-65 mm). Cylinder diameters were 6 mm in eight procedures, 10 mm in four procedures, and 17 mm in one procedure. Wet-field technique was applied in all cases. The endoscope provided a bright field of view even under water. Continuous water irrigation made it easier to observe the entire tumor bed which naturally expanded by water pressure. Gross total resection was achieved in 13 procedures, while subtotal resection was achieved in one procedure. No surgical complications were observed.The endoscopic transcylinder removal using wet-field technique is safe and effective for the removal of symptomatic intracranial supratentorial CMs.

Radiation therapy is a well-established, minimally invasive method of treating brain tumors. In recent years, the number of post-radiotherapy patients has increased, and delayed side effects are evident. De novo aneurysm formation after radiation often manifests as fatal subarachnoid hemorrhage (SAH), resulting in severe clinical outcomes. Nevertheless, the prognosis and therapeutic efficacy of radiation-induced aneurysms (RIAs) remain unclear. Using the PubMed database from 1980 to 2021, we screened 45 articles (53 individual cases) on RIAs; approximately 70% of RIAs were diagnosed after rupture. Of 38 ruptured RIAs, 12 (31.6%) had modified Rankin scale (mRS) 5-6. On the other hand, all unruptured RIAs (15 cases) recovered without neurological deficits (p = 0.012). Ten of the 39 ruptured RIAs were treated surgically, and 22 were treated endovascularly. There was no significant difference in mRS between treatment modalities (p = 0.393), but conservative therapy was significantly related to unfavorable outcomes (p = 0.025). To improve clinical outcomes, RIAs need to be diagnosed before rupture. Surgeons should be aware of de novo aneurysm formation in patients long after radiation therapy.

Aneurysmal subarachnoid hemorrhage (aSAH) may lead to cerebral vasospasm which is significantly associated with morbidity and mortality. Clazosentan, an endothelin-1 receptor antagonist, has been shown to reduce cerebral vasospasm-related morbidity and all-cause mortality compared to placebo in patients with aSAH. To investigate effectiveness of clazosentan combination therapy we conducted a multicenter, retrospective, observational cohort study of Japanese patients with aSAH (35 female; age 64.4 ± 15.0 years old) between June 2022 and March 2023. Of the 47 cases, 29 (61.7%) had favorable outcomes and 9 (19.1%) had unfavorable outcomes. For postoperative aSAH management, clazosentan, cilostazol, and statins were typically used. Fasudil and ozagrel were used in 18 (38.3%) and 15 cases (31.9%), respectively. In 16 cases (34.0%), vasospasm occurred, but vasospasm-related delayed cerebral ischemia (DCI) was reported in only 4 cases (8.5%). Complications of pulmonary edema and hypotension occurred in 19 cases (40.4%) and 16 cases (34.0%), respectively. Risk factors of pulmonary edema were older age, clazosentan discontinuation, positive fluid balance, and lower serum albumin levels. Lower BMI, higher WFNS grade, lower urine output, lower serum albumin were risk factors of hypotension. The risk factors of vasospasm-related DCI were clazosentan discontinuation and positive fluid balance. Hypotension and vasospasm-related DCI were related to unfavorable outcomes. Combination therapy with clazosentan could be effective in preventing post-aSAH vasospasm-related DCI. However, caution must be taken as combination therapy may increase the risk of hypotension and pulmonary edema compared with clazosentan single therapy. Perioperative fluid balance management may be critical for preventing unfavorable outcomes.

Chronic subdural hematoma (CSDH) often causes neurological deterioration and is treated with hematoma evacuation. This study aimed to assess the feasibility of various machine learning models to preoperatively predict the functional outcome of patients with CSDH. Data were retrospectively collected from patients who underwent CSDH surgery at two institutions: one for internal validation and the other for external validation. The poor functional outcome was defined as a modified Rankin scale score of 3–6 upon hospital discharge. The unfavorable outcome was predicted using four machine learning algorithms on an internal held-out cohort (n = 188): logistic regression, support vector machine (SVM), random forest, and light gradient boosting machine. The prediction performance of these models was also validated in an external cohort (n = 99). The area under the curve of the receiver operating characteristic curve (ROC-AUC) of each machine learning-based model was found to be high in both validations (internal: 0.906–0.925, external: 0.833–0.860). In external validation, the SVM model demonstrated the highest ROC-AUC of 0.860 and accuracy of 0.919. This study revealed the potential of machine learning algorithms in predicting unfavorable outcomes at discharge among patients with CSDH undergoing burr hole surgery.

Cerebral revascularization for moyamoya disease (MMD) is an effective treatment for improving cerebral ischaemia and preventing rebleeding. Although direct bypass surgery is commonly performed on older children and adults, it is challenging in very young children due to the high difficulty level of the procedure. The subjects were MMD patients under 3 years of age on whom surgery was performed by a single surgeon (Y.A.). Preoperative clinical findings, information related to direct bypass surgery, bypass patency, and the incidence of postoperative stroke were investigated. Combined revascularization, including direct bypass surgery, was performed on 3 MMD patients (3 sides) under 3 years of age. The average diameter of the grafts used in direct bypass was 0.8 mm. The average recipient diameter was 0.8 ± 0.17 (range 0.6-1) mm. In all cases, the anastomotic procedure was completed using 11-0 monofilament nylon thread, and patency was confirmed. Direct bypass for MMD patients under 3 years old is technically challenging. However, despite the anatomical differences between very young children and elderly individuals, direct bypass surgery could certainly be completed. In addition, a rapid recovery from cerebral blood flow insufficiency could yield a promising neurological outcome.

Iatrogenic vertebral artery (VA) injury in cervical fusion is an extremely rare complication but can lead to serious sequelae. We present two successful cases of internal trapping for preventing delayed-onset ischemic stroke after iatrogenic VA stenosis caused by a cervical pedicle screw. A 34-year-old female underwent posterior cervical fusion for C4/C5 dislocation fracture. No neurological deficits were observed after the operation. However, the postoperative images revealed that the left C5 pedicle screw perforated the transverse foramen, and the left VA was suspected to be occluded at the screw insertion site. Before revision surgery, we tried to embolize the injured VA with coils. A microcatheter could be navigated from the ipsilateral VA to the distal of the screw, and internal trapping was performed with coils. Another case is that of a 50-year-old male with cervical spondylosis, who underwent posterior decompression and cervical fusion. The neurological symptoms did not deteriorate after the operation. However, the postoperative computed tomography images revealed the perforation of the right C3 transverse foramen by the pedicle screw. In right vertebral angiography, about 70% stenosis was observed at the screw insertion site. Although revision surgery was not planned due to good stability, we embolized the right VA after balloon occlusion test, to prevent the delayed-onset thromboembolic complications. Both the patients recovered without any neurological deficits. Iatrogenic VA injuries, even if asymptomatic immediately after surgery, can lead to serious sequelae in case of delayed-onset ischemic stroke. Therefore, careful attention should be paid when the screw perforates the transverse foramen.

Background: The aim of this study was to investigate the association between early postoperative slow flow in bypass grafts and preoperative focal cerebral blood flow (CBF) in patients who underwent combined surgery for moyamoya disease (MMD). Methods: The subjects were 18 patients (22 surgeries) who underwent single photon emission computed tomography (SPECT) before surgery. The CBF value of the middle cerebral artery territory was extracted from the SPECT data, and the value relative to the ipsilateral cerebellar CBF (relative CBF, or RCBF) was calculated. The association between RCBF and early postoperative slow flow in the bypass graft was investigated. In addition, the correlation between the revascularization effect and preoperative RCBF was analyzed. Results: In four of 22 surgeries (18.2%), slow flow in the bypass graft was identified in the early postoperative period. Preoperative RCBF in the slow flow and patent groups was 0.86 ± 0.15 and 0.87 ± 0.15, respectively, with no significant difference (P = 0.72). The signal intensity of four slow-flowed bypasses was improved in all cases on magnetic resonance angiography images captured during the chronic phase (mean of 3.3 months postoperatively). The revascularization scores were 2 ± 0.82 and 2.1 ± 0.68 in the slow flow and patent groups, respectively, and did not differ significantly (P = 0.78). A significant correlation was not observed between preoperative RCBF and the revascularization effect. Conclusion: No significant association was observed between preoperative RCBF and early postoperative slow flow in bypass grafts in patients with MMD undergoing combined surgery. Given the high rate of improved depiction of slow-flowed bypass in the chronic postoperative phase, the conceptual significance of an opportune surgical intervention is to maintain CBF by supporting the patient’s own intracranial-extracranial conversion function.

The straightening phenomenon is known as a cause of catheter kickback in the late phase of coil embolization. The mechanism is supposed to be the relative shortage of the stretch resistance (SR) line, and it occurs when a coil is folded too small. Among many SR coils available, there should be a coil-specific tendency to cause this phenomenon. Here, we conducted an in-vitro experiment to know which coil is the most resistant to the straightening phenomenon. We developed an experimental model to reproduce the straightening phenomenon. Five different coils (Axium Prime, ED Coil, Hypersoft, SMART Coil, and Target 360 nano) of the same size (3 mm × 6 cm) were investigated for five times each. Resistance to the straightening phenomenon, which is represented by the insertion length at the onset of the phenomenon, was compared among coil types. The straightening phenomenon was successfully observed in all insertions. Insertion lengths were significantly different among coil types (p = 0.013). The insertion length of ED was the longest (mean ± SD, 27.0 ± 8.3 mm), which means the most resistant to the phenomenon. Axium was second (21.6 ± 7.0 mm), followed by Target (15.8 ± 6.9 mm), Hypersoft (13.8 ± 5.8 mm), and SMART (12.4 ± 4.7 mm). Difference between ED and Hypersoft (p = 0.037) and difference between ED and Smart (p = 0.018) were significant. ED coil was the one with the most resistance to the straightening phenomenon. Selecting the optimal coil is the key to avoid the phenomenon.

Aneurysms of the large basilar artery (BA) occasionally cause cranial nerve palsy and motor disorder through mass effect. Since 1967, five cases of cerebral aneurysm leading to parkinsonism have been reported. Herein, we describe a rare case of progressive parkinsonism caused by the recurrence of a large aneurysm of the basilar tip after stent-assisted coil embolization. A 66-year-old man visited our hospital with an asymptomatic large aneurysm (maximum diameter, 21 mm) of the BA tip. Magnetic resonance imaging (MRI) revealed no perianeurysmal edema. Coil embolization with a Y-configuration stent with cross-placement was performed. Although thrombus formation occurred and the perforator infarction was complicated, complete occlusion was achieved. Three months later, the patient developed progressive and severe parkinsonism. MRI revealed mild enlargement of the aneurysm and perianeurysmal mesencephalic edema with minor neck recurrence. A trial administration of levodopa and additional stent-assisted coil embolization were performed. Levodopa dramatically improved parkinsonism; thus, the patient’s symptoms were controlled by a continuous levodopa regimen. In a large BA-tip aneurysm patient, moderate regrowth and minor neck recurrence occurred after initial treatment, and chronic compression of the midbrain caused secondary parkinsonism. In such cases, it is important to consider levodopa administration and therapeutic strategies to prevent recurrence or regrowth.

The presigmoid approach (PSA) is selected to obtain more lateral access to cerebellopontine angle tumors, brainstem cavernous malformations, or vertebrobasilar artery aneurysms than the standard retrosigmoid approach. However, mastoidectomy for the PSA can be considered time-consuming and to carry a higher risk of complications due to the anatomical complexity of the region. The authors established a method of minimized mastoidectomy focused on exposing Trautmann’s triangle as the corridor for the PSA while maximizing procedural simplicity and safety and maintaining a sufficient operative view. The authors present their method of minimized mastoidectomy in a cadaver dissection and operative cases, showing potential as a useful option for the PSA.

This study aimed to analyze whether the development of donor vessels after combined revascularization surgery for moyamoya disease (MMD) was related to cerebral blood flow (CBF) changes. We retrospectively reviewed the charts of 11 adult (12 hemispheres) and 13 pediatric (19 hemispheres) patients who underwent combined revascularization in our department. The total vessel cross-sectional area (TVA) was the sum of the cross-sectional areas of the superficial temporal, middle meningeal, and deep temporal arteries imaged using time-of-flight magnetic resonance angiography. The ipsilateral relative CBF (RCBF) on the brain surface in the craniotomy area was calculated by single-photon emission computed tomography. The preoperative and postoperative ratios of the TVA and RCBF were defined as ΔTVA and ΔRCBF, respectively. Finally, we investigated the correlation between ΔTVA and ΔRCBF in adults and children. The TVA and RCBF showed a significant increase after surgery regardless of the age group. However, there was no significant correlation between ΔTVA and ΔRCBF in either the adult or pediatric groups. The adult group had significantly higher ΔRCBF values than the pediatric group (p

BACKGROUND Symptomatic hyperperfusion after cerebral revascularization for pediatric moyamoya disease (MMD) is a rare phenomenon. The authors report a series of patients with this condition. OBSERVATIONS In all three patients in this case series, the combined revascularization was on the left side, the patency of bypass grafts was confirmed after surgery, and focal hyperemia around the anastomotic site was observed on single photon emission computed tomography (SPECT). On the first to eighth days after surgery, all of the patients developed neurological manifestations, including motor aphasia, cheiro-oral syndrome, motor weakness of their right upper limbs, and severe headaches. These symptoms disappeared completely approximately 2 weeks after surgery, and all patients were discharged from the hospital. Quantitative SPECT was performed to determine the proportional change in cerebral blood flow (ΔRCBF) (to ipsilateral cerebellar ratio (denoted ΔRCBF) in the region of interest around the anastomoses, and the mean value was 1.34 (range, 1.29–1.41). LESSONS This rare condition, which develops soon after surgery, requires an accurate diagnosis by SPECT. One indicator is that the ΔRCBF has risen to 1.3 or higher. Subsequently, strategic blood pressure treatment and fluid management could prevent the development of hemorrhagic stroke.

Stroke and neurological outcomes in the early phase following revascularization for moyamoya disease (MMD) may depend on the patient's age. In this study, an age-stratified comparative analysis was performed to clarify this issue. We reviewed 105 MMD patients who underwent 179 revascularization surgeries. The demographic characteristics were collected in four age groups (≤ 5 and 6-17 years for pediatric patients and 18-49 and ≥ 50 years for adults). Additionally, we assessed the incidence of subsequent stroke and deterioration of modified Rankin Scale (mRS) score. Then, we evaluated predictors of postoperative stroke and mRS deterioration using logistic regression. The mean patient age was 26.2 ± 18.5 years. No significant difference in the incidence of postoperative stroke was observed between age groups; however, the incidence tended to be increased among patients aged ≤ 5 years (17.9%) and patients aged ≥ 50 years (16.7%). Deterioration of mRS scores was significantly associated with ages ≤ 5 years (17.9%) and ≥ 50 years (11.1%). Logistic regression showed that posterior cerebral artery involvement (odds ratio [OR], 4.6) and postoperative transient neurological events (TNEs) (OR, 5.93) were risk factors for postoperative stroke. Age ≤ 5 years (OR, 9.73), postoperative TNEs (OR, 7.38), and postoperative stroke (OR, 49) were identified as predictors of unfavorable neurological outcomes. The novel feature of this comparative analysis by age group is that membership in the early-childhood MMD patient group (under 5 years old) was an independent risk factor for unfavorable short-term neurological outcomes and was mainly associated with the incidence of postoperative severe cerebral infarction.

In cases of a dural arteriovenous fistula (AVF) with a pial arterial supply, postoperative hemorrhagic complications occur frequently. Six cases in which patients were diagnosed with a coexisting dural AVF and pial arteriovenous malformation (AVM) sharing a common drainer are presented. These cases were initially thought to be dural AVFs with pial arterial supplies, but careful examination of preoperative images showed that a pial AVM coexisted near the dural AVF, and that both shared a common drainer. The coexistence of a pial AVM is difficult to notice during surgery; for this reason, determining the presence of a pial AVM on preoperative imaging is essential to safely treat a dural AVF with a pial arterial supply. The details of each case, specifically, the diagnostic evidence for this condition (coexisting dural AVF and pial AVM sharing a common drainer), as well as imaging findings that should be noted, are presented.

In superficial temporal artery to middle cerebral artery anastomosis with indirect revascularization for patients with moyamoya disease, the optimal method for selecting the most appropriate cortical artery for the recipient in anastomosis has not been established. We investigated the relationship between the fluorescence emission timing of the recipient artery in the preanastomosis indocyanine green videoangiography and operative outcomes. This retrospective study included 51 surgical revascularization procedures for 39 moyamoya disease patients. The enrolled surgical procedures were classified into three groups based on the fluorescence emission timing of the recipient artery in preanastomosis indocyanine green videoangiography: the EARLIEST, the INTERMEDIATE, and the LATEST. Clinical characteristics and operative outcomes were also collected. The occurrence of white thrombus at the anastomosis site and symptomatic hyperperfusion showed significant differences between the groups classified by the fluorescence emission timing of the recipient artery in preanastomosis indocyanine green videoangiography (white thrombus, p = 0.001; symptomatic hyperperfusion, p = 0.026). The development of white thrombi was significantly higher in the LATEST group, and all symptomatic hyperperfusion was observed in the EARLIEST group. These results indicated that the LATEST group had a significantly higher risk for developing white thrombus, and the EARLIEST group was prone to occur symptomatic hyperperfusion. Selecting the recipient artery based on evaluating the fluorescence emission timing in preanastomosis indocyanine green videoangiography may be useful in reducing perioperative complications.

Internal trapping with coils is an established treatment of symptomatic large non-branching thrombosed fusiform vertebral artery aneurysms (VAA). However, when perforators arise near the aneurysm neck, parent artery occlusion has a high risk of causing medullary infarction. As an alternative treatment, we performed short-segment internal trapping of the artery using n-butyl-2-cyanoacrylate (NBCA) and coils (bird's nest trapping). Before treatment, perianeurysmal perforators are carefully detected using high-resolution three-dimensional rotational angiography (3DRA). Double microcatheters are advanced to the distal portion of the aneurysm through a balloon guiding catheter where coils are deployed without tight packing. Then, NBCA is injected into the coil mass, taking care to preserve perforators and significant branches. The same maneuver is repeated in the proximal portion of the aneurysm. Coil placement is avoided within the middle of the aneurysm; however, if necessary, only a small number of coils are placed to prevent worsening of mass effect. Two quinquagenarian males presented with a large thrombosed fusiform VAA that caused symptoms due to mass effect. In each case, perforators arose from the parent artery and short-segment internal trapping with NBCA and coils was performed. Symptoms improved after treatment and follow-up imaging confirmed aneurysm shrinkage with no long-time recurrence. In symptomatic large fusiform VAAs where the distance from the lesion to important perforators is extremely short, internal trapping using a combination of NBCA and coils can be more useful than conventional internal trapping.

The carotid sinus reflex (CSR) is a rare complication of the Pipeline Embolization Device (PED) deployment. No study has assessed the potential risk factors in a case series. The purpose of this study was to examine CSR triggering during PED deployment. Thirty-seven consecutive patients who underwent PED deployment were included. All procedures were performed under local anesthesia with mild sedation. We retrospectively analyzed patient characteristics, PED deployment time, and vital signs during the procedure. The vital signs included the pulse rate (PR) and systolic blood pressure (SBP) obtained at three timepoints (pre-deployment, during deployment, post-deployment). We examined the triggering of the CSR during PED deployment by comparing the vital signs at the three timepoints. Moreover, risk factors for CSR were analyzed with univariate analysis. The patients' average age was 66.3 years. The average size of the aneurysm was 18.0 mm. Six patients (16.2%) showed a decline in the SBP or PR defined as CSR. One patient had a transient cardiac arrest and two had severe transient bradycardia. Deployment into the ophthalmic segment of the internal carotid artery (C2 segment) aneurysm (p = 0.022), prolonged PED deployment time more than 14.5 minutes (p = 0.005), and an acute angle of the anterior genu less than 51.5 degrees (p = 0.005) were risk factors in triggering CSR. CSR may be triggered during PED deployment under local anesthesia with mild sedation. Deployment to the C2 segment aneurysm, prolonged PED deployment time, and an acute angle of the anterior genu were associated with CSR triggering.

Cone beam computed tomography (CBCT) images are degraded by artifacts due to endovascular implants. We evaluated the use of streak metal artifact reduction technique (SMART) in non-contrast CBCT images after endovascular neurosurgery obtained from 148 patients (125 with aneurysm and 23 with dural arteriovenous fistula [dAVF]). Three neurosurgeons evaluated the cistern and brain surface visibility in CBCT images with and without SMART correction based on a 4-point scale (1, excellent; 2, good; 3, limited; and 4, insufficient). Significant improvement in visibility was achieved when the median scores improved from 4 or 3 to 2 or 1 or from 2 to 1. Metal artifact reduction in adjacent slices without metal and new artifacts after SMART correction was also examined. A significant improvement was achieved regarding the visibility of the cistern in 90 (60.8%) images and of the brain surface in 108 (73.0%) images. Metal size (cistern: odds ratio [OR], 0.91 per 1 mm increase; 95% confidence interval [CI], 0.83–0.99), irregular metal shape (cistern: OR, 0.18; 95% CI, 0.05–0.60 and brain surface: OR, 0.15; 95% CI, 0.05–0.45), and infratentorial lesions (cistern: OR, 0.37; 95% CI, 0.14–0.96 and brain surface: OR, 0.30; 95% CI, 0.11–0.80) were negatively correlated with improved visibility. Metal artifact reduction in adjacent slices without metal was obtained in 25.6% and 34.8% of images with aneurysm and dAVF, respectively. New artifacts after SMART correction were found in 4.8% and 13.0% of images with aneurysm and dAVF, respectively. SMART is especially effective for supratentorial small aneurysms.

Moyamoya disease (MMD) causes intracranial arterial stenosis progression. The progression of intracranial arterial stenosis will increase the risk of ischemic cerebrovascular events. This study aims to investigate the relationship between intracranial arterial stenosis progression, vessel wall enhancement (VWE), and the recent neurological symptoms. A total of 39 MMD patients (12 male; 37.6 ± 18.0 years old) were registered in this study analysis between April 2016 and July 2018. All patients received MRI at registration and 6, 12, and 24 months post-registration. The incidence of ischemic cerebrovascular events (transit ischemic attacks or cerebral infarction) was checked until December 2018. We evaluated the relationship between the intensity of VWE, intracranial arterial stenosis, and the recent neurological symptoms. During the mean follow-up period of 13.8 ± 5.5 months, the changes in VWE were observed in 33 hemispheres (42.3%), stenosis progression was observed in 21 hemispheres (26.9%), and recent neurological symptoms occurred in 10 hemispheres (12.8%). Stenosis progression was observed in 11 hemispheres (33.3%) in the VWE(+) group and ten hemispheres (22.2%) in the VWE(-) group (p = 0.310). The recent neurological symptoms were observed in eight hemispheres (21.2%) in the VWE(+) group and two hemispheres (4.44%) in the VWE(-) group (odds ratio 6.88, 95% confidence interval 1.35-34.98, p = 0.015). The intensity of VWE sometimes changes. The changes in VWE were significantly associated with the recent neurological symptoms but not with stenosis progression.

Cerebral revascularization surgery has been established as an effective treatment for moyamoya disease. On the other hand, harvesting grafts and tissues to nourish the scalp may increase the risk of postoperative wound-related complications. The purpose of this study was to clarify risk factors for wound-related complications after examining the relationship with the surgical design.We retrospectively analyzed 115 patients who underwent 197 revascularization procedures between October 2004 and March 2019. The design of the revascularization was classified into 6 types, then further classified according to the number of grafts harvested, resulting in 11 subtypes. Incidences of minor and major wound-related complications for the 11 different surgical designs were assessed. The risk of complications from each design was statistically examined. In addition, the yearly transition rate of complications was also investigated.Wound-related complications occurred in 38 of the 195 operations (19.5%), including 10 major events (26.3%) and 28 minor events (73.7%). Significant differences in the incidence of complications were seen according to surgical design (P0.05), with complications significantly more frequent for L(a) double type and L(p) double type and less frequent for L(a) single type and L(p) single type. In addition, significant differences were found in the incidence and degree of complications according to the number of grafts (0-2) (P0.05). The incidence of wound-related complications has clearly decreased since 2015.Wound-related complications were more frequent and tended to become more severe with double-bypass procedures but were clearly improved under a plastic surgery approach.

We examined the specific changes that occur in the expression levels of extracellular vesicle (EV)-derived microRNAs (miRNAs) in intracranial cerebrospinal fluid (CSF) in moyamoya disease. Patients with arteriosclerotic cerebral ischemia were used as controls to eliminate the effects of cerebral ischemia. Comprehensive expression analysis of miRNAs extracted from EVs by next-generation sequencing (NGS) and validation by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed. Experiments were conducted on eight cases of moyamoya disease and four control cases. In the comprehensive miRNA expression analysis, 153 miRNAs were upregulated and 98 miRNAs were downregulated in moyamoya disease compared to the control (q-value 1). qRT-PCR performed on the four most valuable miRNAs (hsa-miR-421, hsa-miR-361-5p, hsa-miR-320a, and hsa-miR-29b-3p) associated with vascular lesions among the differentially expressed miRNAs gave the same results as miRNA sequencing. In GO analysis for the target genes, cytoplasmic stress granule was the most significant GO term. This study is the first comprehensive expression analysis of EV-derived miRNAs in the CSF of moyamoya disease patients using NGS. The miRNAs identified here may be related to the etiology and pathophysiology of moyamoya disease.

OBJECTIVE The protocol for antiplatelet therapy after stent-assisted coil embolization (SACE) for intracranial aneurysms is not well established. In particular, the indications for single antiplatelet therapy (SAPT) discontinuation remain controversial. The authors investigated the long-term outcomes of SAPT discontinuation after SACE among patients at a single institution. METHODS Patients who underwent SACE during the period from 2010 to 2020 and who were followed up for > 1 year were included in this study. The delayed ischemic and hemorrhagic complication rates were examined during follow-up. Moreover, the risk factors of antiplatelet therapy reduction or discontinuation and the outcomes of SAPT discontinuation were examined. RESULTS In total, 240 patients were included in the analysis. The average patient age was 60.3 years, and the average follow-up period was 46.7 months. Nine (3.8%) patients presented with symptomatic delayed ischemic complication, and 3 (1.3%) patients experienced a decline in modified Rankin Scale score. The stent configuration (T- or Y-stent) was the only risk factor associated with delayed ischemic complication (p < 0.001). SAPT was discontinued in 147 (71.7%) of 205 patients who were followed up for > 2 years, and no ischemic complications were observed. CONCLUSIONS It is safe to discontinue SAPT in patients without ischemic complications and with stable intraaneurysmal signals on MRA 2 years after SACE. The T- or Y-stent is a high-risk factor for delayed ischemic complications, and antiplatelet therapy reduction or discontinuation should be cautiously considered.