Passive approximator vascular closure device use in patients with shallow femoral artery depth increases puncture-site complications in neuroendovascular treatment.

OBJECTIVE: Puncture-site complications in interventional radiology sometimes cause severe conditions. Vascular closure devices play an important role in preventing puncture-site complications. Vascular closure devices are divided into two types, the directly suturing or clipping type (active approximators) and adherent sealant types (passive approximators). However, which types of vascular closure device are the safest and most effective for achieving hemostasis remains unclear. We analyzed the efficacy of each type of vascular closure device and risk factors for puncture-site complications. METHODS: This study investigated 327 consecutive cases of neuroendovascular surgery using a transfemoral procedure during a 2-year study period. Passive approximators (Angioseal and Exoseal) were mainly used in the first half and active approximators (Perclose) in the second. We compared groups and estimated risk factors for puncture-site complications. RESULTS: All procedures were successful. Comparing groups with and without puncture-site complications, use of passive approximators and ≥3 antithrombotic medications tended to be more frequent and distance from skin to femoral artery and body mass index tended to be lower in the group with complications without significant. The cutoff for femoral artery depth calculated from a receiver operating characteristic curve was 16.43 mm. Multivariate analysis revealed ≥3 antithrombotic medications (p=0.002, OR 15.29, 95%CI 2.76-85.76) and passive approximator use in patients with femoral artery depth <16.43 mm (p<0.001, OR 17.08, 95%CI 2.95-57.80) were significantly higher in the group with puncture-site complications. CONCLUSIONS: Passive approximator use in patients with shallow femoral artery depth increases puncture-site complications in neuroendovascular treatment.

Preoperative Blood Counts Predict Overall Survival in Patients Undergoing Surgical Removal of Brain Metastasis.

OBJECTIVE: The prognosis for patients with cancer with brain metastasis (BM) requiring surgical removal is quite limited. Preoperative prognostic factors can provide meaningful information to surgeons, oncologists, and patients. This study evaluated the preoperative blood counts in patients with BM who were treated with surgical removal. METHODS: Between January 2011 and November 2021, 221 consecutive surgeries were conducted on 198 patients with BM. Among the 198 patients, 188 patients with sufficient blood test data and follow-up were analyzed in this study. The tumors originated from the lungs (n = 102, 54.3%), colon (n = 26, 13.3%), breast (n = 13, 6.9%), kidney (n = 8, 4.3%), stomach (n = 6, 3.2%), and others (n = 33, 17.6%). The blood test data included neutrophils, lymphocytes, monocytes, eosinophils, basophils, red blood cell count, hemoglobin, and albumin. RESULTS: The median follow-up and median survival times were both 11 months (range: 0-139 months). Higher neutrophil-lymphocyte ratio ≥ 3.17, platelet-lymphocyte ratio ≥112.7, systemic immune-inflammation index ≥594.4, systemic inflammation response index ≥1.25 were unfavorable predictors of prognosis for the patients treated with surgical removal for BM (P < 0.001). Furthermore, lower lymphocyte-monocyte ratio < 2.33 and prognostic nutritional index < 48.5 were unfavorable predictors. CONCLUSIONS: Simple, less expensive, routinely ordered preoperative blood count assessments, such as the neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, lymphocyte-monocyte ratio, systemic immune-inflammation index, systemic inflammation response index, and prognostic nutritional index, can predict the overall survival of patients treated with surgical removal for BM.

Pre-treatment systemic inflammation response index and systemic immune inflammation in patients with primary central nerve system lymphoma as a useful prognostic indicator.

PURPOSE: The systemic inflammation response index (SIRI) and systemic immune-inflammation index (SII) are based on neutrophil, monocyte, platelet, and lymphocyte counts. The SIRI and SII are used to predict the survival of patients with malignant tumors. It is well known that the inflammatory immune response is closely related to cancer occurrence and progression. In the present study, we evaluated the potential prognostic significance of SIRI and SII in patients with primary central nervous system lymphoma (PCNSL). METHODS: Fifty-eight consecutive patients were enrolled in this study between November 2006 and May 2022. Among the 58 patients, 47 patients with sufficient blood test data and follow-up were analyzed. The patients with steroid intake at the time point of the blood test and higher C-reactive protein were excluded. RESULTS: The median follow-up and survival times were 31 and 36 months, respectively. The optimal cutoff SIRI value was based on the receiver operating characteristic curve (ROC) for overall survival (OS) and stratified patients into low (< 1.43 × 109/L, n = 22) and high (≥ 1.43 × 109/L, n = 25) SIRI groups. The optimal cutoff SII value based on the ROC for OS stratified patients into low (< 694.9, n = 28) and high (≥ 694.9, n = 19) SII groups. A low SIRI value was associated with longer OS (p = 0.006). Furthermore, a low SII value was associated with longer OS (p = 0.044). The prognostic factors associated with prolonged survival in univariate analysis using the Cox proportional hazard model were age < 65 years, low SIRI, and low SII. The multivariate analysis demonstrated that age < 65 years and low SIRI independently predicted longer OS. CONCLUSION: Simple, less expensive, and routinely ordered preoperative blood count assessments such as SIRI and SII predict the OS of patients with PCNSL. This study demonstrated that PCNSL is associated with pre-treatment systemic immune-inflammation states.

Medulla and cervical cord contrast-induced encephalopathy detected by neuromonitoring during coil embolization of posterior circulation aneurysms.

Understanding the risks of contrast-induced encephalopathy (CIE), a serious complication of contrast agents, is crucial in endovascular treatment. We present the case of a 73-year-old woman who developed CIE in the medulla and cervical cord during coil embolization for unruptured left basilar-superior cerebellar artery and basilar artery tip aneurysms. The CIE was identified via neuromonitoring. In this case, spinal cord ischemia might have occurred due to reduced perfusion pressure after inserting the distal access catheter (DAC) in the vertebral artery. Multiple injections of contrast medium via the DAC during coil embolization likely contributed to an unusual form of CIE. Extreme caution is warranted during endovascular treatments involving the posterior circulation, due to the relatively high incidence of contrast-mediated encephalopathy, which can lead to severe consequences such as perforator infarction. Neuromonitoring is very useful for the early detection of neurological changes, particularly because intraoperative angiography may not reveal all irregularities.

Long-term outcomes and potential predictive recurrence factors after endonasal endoscopic surgical treatment of symptomatic Rathke's cleft cysts.

Although patients with symptomatic Rathke's cleft cysts (RCCs) receive surgical treatment, recurrence sometimes occurs after surgery. However, the mechanism underlying recurrence remains unclear. We evaluated the outcomes of RCC decompression over a long-term follow-up period. We retrospectively reviewed the medical records of 35 patients with symptomatic RCC who underwent endonasal endoscopic surgery (EES) at our institution between 2008 and 2023. Patients' characteristics, intraoperative findings, and postoperative follow-up outcomes were evaluated. A univariate regression model was used to identify the predictors of recurrence. The median patient age was 48.0 years, and 74.2% of the patients were female. The mean follow-up duration was 94.7 ± 47.6 months. Cyst content recurrence was observed in 15 patients (42.8%). Five patients (14.2%) with symptomatic recurrence underwent reoperation. Postoperative vision improved in all 23 patients (100%); headaches improved in 20 patients (90.9%). A new hormonal deficit occurred in two patients (5.7%). Complications included intraoperative cerebrospinal fluid (CSF) leak in 10 patients (28.5%), postoperative CSF leak in two patients (5.7%), permanent diabetes insipidus in two patients (5.7%), and postoperative infection in three patients (8.5%). Univariate analyses revealed that the position of the anterior pituitary lobe (p = 0.019) and preoperative visual disturbances (p = 0.008) significantly affected recurrence after surgery. Although EES was efficient, the recurrence rate was relatively high over a long-term period. The anterior pituitary lobe position and preoperative visual disturbances were significantly associated with recurrence. The anterior-inferior position can predict a high risk of recurrence before surgery.

Case report: Giant pituitary neuroendocrine tumor presented along with acute visual loss due to pituitary apoplexy after receiving COVID-19 vaccination.

Objective: A case of giant pituitary neuroendocrine tumor presented along with acute visual loss due to pituitary apoplexy after receiving a COVID-19 vaccination is reported. Case presentation: A 45-year-old man was referred for a giant pituitary tumor with bitemporal hemianopsia. A surgical procedure was planned and then delayed due to the COVID-19 outbreak in Japan, with a Pfizer/BioNTech vaccine administered while awaiting surgery. Three days after the second COVID-19 vaccination the patient noted a progressively worsening headache that caused pituitary apoplexy and then a decrease in vision. Emergency surgery was thus performed. Conclusion: Pituitary apoplexy is a rare and life-threatening complication that may occur after undergoing a COVID-19 vaccination.

Dual-layered stents reduce cerebral embolism compared with first-generation stents during carotid stenting of high lipid core plaque lesions.

BACKGROUND: Periprocedural lipid core plaque (LCP) has been detected in carotid arteries assessed by catheter-based near-infrared spectroscopy (NIRS). High LCP is associated with cerebral embolism after carotid artery stenting (CAS) using a first-generation stent. We aimed to evaluate whether dual-layered stents reduce embolic infarcts in patients with high LCP and change of lipid signal as assessed by NIRS during CAS. METHODS: Participants comprised 210 consecutive patients undergoing CAS. The study was divided into two distinct periods, with first-generation closed-cell stents used in the earlier period and dual-layered stents used in the later period. NIRS was performed at baseline, after stent implantation, and after balloon post-dilatation to analyze maximal lipid core burden index at minimal luminal area (max-LCBIMLA). RESULTS: The ipsilateral cerebral embolism rate was significantly lower with dual-layered stents (9%) than with first-generation stents (33%, p<0.001), particularly with highly lipidic lesions (12% vs 60%, p<0.001). On multivariate logistic regression analysis, high LCP and first-generation stent usage were factors related to ipsilateral cerebral embolism (both p<0.001; OR 8.28 (95% CI 3.49 to 19.64) and OR 8.07 (95% CI 2.33 to 27.93), respectively). Max-LCBIMLA decreased significantly after stenting in both groups (both p<0.01) and max-LCBIMLA after balloon post-dilatation was significantly lower with dual-layered stents (22.4±65.6) than with first-generation stents (124.2±208.2; p=0.006). CONCLUSIONS: Dual-layered stents reduce embolic infarcts in patients with highly lipidic plaque lesions as assessed by NIRS who undergo CAS. Dual-layered stents significantly reduced NIRS-derived lipid signals after stenting.

Intraoperative Ventricular Opening has No Effect on Complication Development Following BCNU Wafer Implantation for Malignant Glioma.

OBJECTIVE: To evaluate the safety profile of bis-chloroethyl-nitrosourea (BCNU) wafer implantation after malignant glioma resection with or without ventricular opening (VO). METHODS: This single-center retrospective study included 66 consecutive patients with BCNU wafer implantation after malignant glioma resection between March 2013 and August 2021. The patients were categorized into 2 groups based on whether VO occurred during the malignant glioma resection. Fifty-eight patients had glioblastoma, and 8 had anaplastic astrocytoma or oligodendroglioma. Forty-eight patients underwent an initial treatment, and 18 underwent recurrent surgeries. Infection, hydrocephalus, subcutaneous fluid collection, chronic subdural hematoma, early seizure after surgery within 1 month, symptomatic edema surrounding the resected cavity, cyst formation, and postoperative hemorrhage were defined as adverse events (AEs). RESULTS: Thirty-three patients underwent resection with VO, and 33 without. The median survival time was 28 months in the initial treatment group and 11.5 months in the recurrent treatment group. The with and without VO groups had similar median survival times. Postoperative AEs occurred in 7/33 patients (21.2%) with VO and 10/33 (30.3%) without VO, with no difference between them (P = 0.574). CONCLUSIONS: This study showed that VO during surgery with BCNU wafer implantation might not influence the occurrence of postoperative AEs. If VO happens, BCNU wafer implantation can be performed safely with accurate closing of the ventricle.

Long-Term Survival after Linac-Based Stereotactic Radiosurgery and Radiotherapy with a Micro-Multileaf Collimator for Brain Metastasis.

BACKGROUND: this study aimed to evaluate the prognostic factors associated with long-term survival after linear accelerator (linac)-based stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (fSRT) with a micro-multileaf collimator for brain metastasis (BM). METHODS: This single-center retrospective study included 226 consecutive patients with BM who were treated with linac-based SRS or fSRT with a micro-multileaf collimator between January 2011 and December 2018. Long-term survival (LTS) was defined as survival for more than 2 years after SRS/fSRT. RESULTS: The tumors originated from the lung (n = 189, 83.6%), breast (n = 11, 4.9%), colon (n = 9, 4.0%), stomach (n = 4, 1.8%), kidney (n = 3, 1.3%), esophagus (n = 3, 1.3%), and other regions (n = 7, 3.1%). The median pretreatment Karnofsky performance scale (KPS) score was 90 (range: 40-100). The median follow-up time was 13 (range: 0-120) months. Out of the 226 patients, 72 (31.8%) were categorized in the LTS group. The median survival time was 43 months and 13 months in the LTS group and in the entire cohort, respectively. The 3-year, 4-year, and 5-year survival rate in the LTS group was 59.1%, 49.6%, and 40.7%, respectively. Multivariate regression logistic analysis showed that female sex, a pre-treatment KPS score ≥ 80, and the absence of extracranial metastasis were associated with long-term survival. CONCLUSIONS: female sex, a favorable pre-treatment KPS score, and the absence of extracranial metastasis were associated with long-term survival in the current cohort of patients with BM.

Endovascular mechanical thrombectomy for cerebral venous sinus thrombosis after mRNA-based SIRS-CoV-2 vaccination.

Background: As vaccinations against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue worldwide, increased rates of venous thrombotic events, mainly as cerebral venous sinus thrombosis (CVST), have been reported following adenovirus vector-based SARS-CoV-2 vaccination. However, few reports have described the occurrence of venous thrombosis after messenger RNA (mRNA)-based vaccination. Here, we describe a case of CVST after a first dose of mRNA-based vaccination that was treated with emergent endovascular mechanical thrombectomy and systemic heparinization.Case Description.A 43-year-old, previously healthy man suffered severe headache and partial seizures affecting the left arm 4 days after receiving the first dose of an mRNA-based SARS-CoV-2 vaccination (FC3661; Pfizer/BioNTech). Computed tomography showed intraparenchymal hemorrhage. Seven days after vaccination, symptoms worsened and he was transferred to our tertiary hospital. Magnetic resonance venography revealed CVST with occlusion of the superior sagittal sinus (SSS) and right transverse sinus (TS). Since no findings suggested thrombosis with thrombocytopenia syndrome, the patient underwent systemic heparinization and emergent mechanical thrombectomy with balloon transluminal angioplasty, a stent retriever and an aspiration catheter. Complete SSS and right TS recanalization were achieved and the patient was discharged without neurological deficits. Conclusion: Clinicians should be aware that apparently healthy individuals with no risk factors can develop CVST after receiving an mRNA-based vaccine and appropriate treatment including EMT need to be performed immediately.(228 words).

Impact of surgical factors on delayed hyponatremia in patients with nonfunctioning pituitary adenoma after endonasal endoscopic transsphenoidal procedure.

PURPOSE: Delayed hyponatremia can occur after pituitary surgery, resulting in prolonged hospitalization. However, the influence of surgical factors after such a procedure has not been well established. The impact of surgery and related factors on delayed hyponatremia was investigated. METHODS: This was a retrospective analysis of 137 consecutive patients who underwent transsphenoidal surgery for a nonfunctioning pituitary adenoma between 2008 and 2019. Preoperative (demographics, comorbidities), intraoperative (resection extent, operation time, blood loss volume, cerebrospinal fluid leak, tumor consistency), and postoperative [hematoma, meningitis, diabetes insipidus (DI), hormonal assessment] data were collected, with statistical analysis of each factor performed. RESULTS: Among the 137 patients, delayed hyponatremia occurred in 31 (22.6%). Multivariate analysis revealed that those with hypertension had a significantly higher likelihood of avoiding delayed hyponatremia (p = 0.004). Although no correlations of direct surgical factors with delayed hyponatremia were found, multivariate analysis of indirect surgical factors showed that presence of a firm tumor, transient DI, and meningitis were significantly associated with delayed hyponatremia (p = 0.014, 0.001, and 0.047, respectively). There was also a significant association of severe hyponatremia with appearance of symptoms (p = 0.002). CONCLUSION: There was a tendency for hypertension to be associated with delayed hyponatremia avoidance, with indirect surgical factors including tumor consistency, transient DI, and meningitis found to have an influence on delayed hyponatremia. It was concluded that attention should be given to non-hypertensive patients with a firm tumor, transient DI, or meningitis after pituitary surgery, as delayed hyponatremia may occur.

Awake Craniotomy for Subcortical Brain Metastasis Beneath the Speech Center: A Technical Case Report.

BACKGROUND: To preserve language function, intraoperative functional brain mapping (IFBM) in and near the speech center is essential. CASE REPORT: We present a case of a 73-year-old right-handed woman with colon cancer. She presented with mild speech disturbance. Magnetic resonance imaging revealed a ringed enhancing lesion in the frontal operculum. The preservation of language function was critical; therefore, she underwent awake craniotomy using IFBM. Thus, the speech site was elicited by cortical electrical stimulation at the surface, near the location of the tumor. We made a safe corticotomy on the surface of the lesion and performed the resection of brain metastasis (BM) via a safety corridor. We achieved gross total resection of the BM while preserving the language function. After surgery, she recovered from speech disturbance. She returned to her normal life with improved language function. CONCLUSION: IFBM is a useful tool to undertake a safe approach via the speech center, avoiding permanent language deficits.

Awake Surgery for Local Recurrence of Brain Metastasis in the Precentral Gyrus After Fractionated Stereotactic Radiotherapy: A Technical Case Report.

BACKGROUND: To avoid permanent neurologic deficits and preserve brain function, intraoperative electrical stimulation mapping (IESM) is essential for surgical resection. CASE REPORT: A 59-year-old right-handed woman with ovarian cancer who had undergone stereotactic radiotherapy for brain metastasis two years before, was introduced due to progressive left upper paresis. Magnetic resonance imaging showed a recurrence of the lesion. We performed awake surgery using IESM. Thus, the sensorimotor site was elicited on the precentral and postcentral gyrus. However, IESM elicited no disturbance of motor function on the surface of the posterior part of the precentral gyrus. We made a safe corticotomy on it, and performed the resection of recurrent BM. Preserving the motor and sensory function, we achieved the resection of BM. After surgery, she experienced a significant improvement in motor function. CONCLUSION: IESM is a useful tool to make a safe approach via the precentral gyrus avoiding permanent sensorimotor deficits.

Low relative diffusion weighted image signal intensity can predict good prognosis after endovascular thrombectomy in patients with acute ischemic stroke.

BACKGROUND: It is vital to identify a surrogate last-known-well time to perform proper endovascular thrombectomy in acute ischemic stroke; however, no established imaging biomarker can easily and quickly identify eligibility for endovascular thrombectomy and predict good clinical prognosis. OBJECTIVE: To investigate whether low relative diffusion-weighted imaging (DWI) signal intensity can be used as a predictor of good clinical outcome after endovascular thrombectomy in patients with acute ischemic stroke. METHODS: We retrospectively identified consecutive patients with acute ischemic stroke who were treated with endovascular thrombectomy within 24 hours of the last-known-well time and achieved successful recanalization (modified Thrombolysis in Cerebral Infarction score ≥2b). Relative DWI signal intensity was calculated as DWI signal intensity in the infarcted area divided by DWI signal intensity in the contralateral hemisphere. Good prognosis was defined as a modified Rankin Scale score of 0-2 at 90 days after stroke onset (good prognosis group). RESULTS: 49 patients were included in the analysis. Relative DWI signal intensity was significantly lower in the group with good prognosis than in the those with poor prognosis (median (IQR) 1.32 (1.27-1.44) vs 1.56 (1.43-1.66); p<0.01), and the critical cut-off value for predicting good prognosis was 1.449 (area under the curve 0.78). Multiple logistic regression analysis revealed association of good prognosis after endovascular thrombectomy with low relative DWI signal intensity (OR=6.84; 95% CI 1.13 to 41.3; p=0.04). CONCLUSIONS: Low relative DWI signal intensity was associated with good prognosis after endovascular thrombectomy. Its ability to predict good clinical outcome shows potential for determining patient suitability for endovascular thrombectomy.

Active management of the target P2Y12 reaction unit range in patients undergoing stent-assisted coil embolization for unruptured cerebral aneurysms.

BACKGROUND: Platelet function tests have been increasingly adopted to measure patient responses to antiplatelet drugs, and to predict complications. However, no established optimal antiplatelet management for stent-assisted coil embolization (SAC) have been established. The purpose of the present study was to investigate the efficacy and feasibility of clopidogrel dose adjustment for active target P2Y12 reaction unit (PRU). METHODS: A total of 202 consecutive patients undergoing SAC to treat unruptured intracranial aneurysms were prospectively recruited. All patients were given two antiplatelet agents starting 7 days prior to the procedure, and platelet function was measured with the VerifyNow test. Clopidogrel hyper-responsive patients received reduced dosing according to the values of follow-up PRUs before and 7, 14, 30, and 90 days after the procedure. Patients were divided into three groups according to clopidogrel responsiveness before treatment, and clinical outcomes and time in target PRU ranges (TTR) were analyzed. RESULTS: No delayed ischemic or hemorrhagic events occurred that were associated with out-of-range PRU. PRU values in the hypo-responsive and hyper-responsive groups significantly improved 7 days after treatment with active target PRU management (p=0.05,<0.001, respectively). PRU values were controlled within the target PRU range with drug adjustment (p=0.034), and the time in TTR for all patients was 97% (4.8%-100%), which showed the feasibility of optimal control of PRU values with the protocol. CONCLUSION: Active target PRU management can achieve control of optimal PRU values and may decrease perioperative ischemic and hemorrhagic events among patients undergoing SAC.

Ocular blood flow by laser speckle flowgraphy to detect cerebral ischemia during carotid endarterectomy.

Laser speckle flowgraphy (LSFG) is a noninvasive technique that can measure relative blood flow velocity in the optic fundus contributed by the ophthalmic artery, the main first branch originating from the internal carotid artery (ICA). The aim of this study was to assess the feasibility of ocular blood flow measurement by LSFG to detect ischemic stress due to carotid clamping during carotid endarterectomy (CEA). Nineteen patients undergoing CEA with ocular blood flow measurement by LSFG and intraoperative monitoring (IOM) were prospectively enrolled between August 2016 and March 2019. The mean blur rate (MBR) of ocular blood flow by LSFG, representing relative blood flow of the branch of the retinal artery originating from the optic nerve head, was compared between before and after carotid clamping during CEA. The correlation between the reduction ratio of MBR and the regional saturation oxygen (rSO2) index by near infrared spectroscopy was investigated. Ocular blood flow measurement by LSFG could not be performed in one patient with a severe cataract. In the other 18 patients, LSFG could be performed in all 106 sessions during surgery. The MBR reduction ratio between before and after carotid clamping ranged from - 12 to 100%. The MBR reduction ratio was positively correlated with the rSO2 index (r = 0.694, 95% confidence interval: 0.336-0.877, p = 0.001). The MBR reduction ratio of ocular blood flow by LSFG after carotid clamping was significantly correlated with the rSO2 index. The ocular blood flow by LSFG could be considered an adjunct modality for evaluating cerebral ischemic tolerance during CEA.

Delayed Intracranial Parenchymal Changes After Aneurysmal Coil Embolization Procedures for Unruptured Intracranial Aneurysms.

BACKGROUND: With the recent advances in endovascular treatment devices, it has become standard in wide-neck or large intracranial aneurysms to perform coil embolization with adjunctive techniques. However, device-related perioperative complications have been reported because of the use of more complex systems. OBJECTIVE: To investigate patients who developed multiple parenchymal lesions after undergoing coil embolization for treating an unruptured intracranial aneurysm. METHODS: This study investigated 305 consecutive patients who underwent coil embolization of unruptured intracranial aneurysms between 2015 and 2017. Delayed inflammatory changes referred to the delayed observation of multiple cerebral white matter lesions on follow-up magnetic resonance imaging at an area corresponding to the perfused area of the treatment target vessel. The timing and pattern of onset, device used, the combined use of adjunctive techniques, and the clinical course after steroid treatment were retrospectively investigated. RESULTS: The 7 patients (2.3%) who showed delayed inflammatory changes were all women with a mean age of 59 yr. A mean duration from treatment to onset was 28 d. Symptoms were convulsions in 3 patients, hemiplegia in 2 patients, and homonymous hemianopia in 1 patient. All 7 patients were treated with adjunctive technique including stents, double catheter method, and balloon assist. Response to steroid treatment was satisfactory both clinically and on imaging in all 7 patients. Skin patch test was positive for nickel allergy in 2 patients. CONCLUSION: Clinicians must be fully aware of symptomatic delayed inflammatory changes may occur after endovascular aneurysmal treatment with the use of various devices.

Extensive postoperative subdural fluid volume affects the onset of chronic subdural hematoma after unruptured aneurysmal clipping surgery.

OBJECTIVE: To evaluate risk factors associated with chronic subdural hematoma (CSDH) onset after clipping surgery for unruptured intracranial aneurysm, and determine whether intraoperative conventional arachnoid-plasty (ARP) can suppress the CSDH onset by reducing subdural fluid volume. PATIENTS AND METHODS: We retrospectively evaluated 217 patients who underwent surgical clipping at our institution from 2012 to 2018. Risk and predictive factors for symptomatic CSDH development including clinical characteristics, postoperative subdural fluid volume, Hounsfield unit (HU) value of subdural fluid density evaluated by CT and the effect of conventional ARP were compared between CSDH and non-CSDH groups. RESULTS: Of 217 patients who underwent surgical clipping for anterior circulation aneurysm, 209 were included in this study. Among whom, postoperative CSDH, required burr irrigation, occurred in 12 (5.7%). Mean age was significantly higher in the CSDH group (70 ± 8 years) than in the non-CSDH group (64 ± 11 years, p = 0.03). Subdural fluid volumes on postoperative day (POD)1, POD8 and POD30 were significantly larger in the CSDH group than in the non-CSDH group (38.4 ± 33.5 cm3, 54.8 ± 36.3 cm3, 77.2 ± 36.1 cm3 vs 10.0 ± 7.7 cm3, 16.1 ± 12.8 cm3, 14.0 ± 17.5 cm3, p < 0.001, respectively). However, intraoperative conventional ARP did not reduce postoperative subdural fluid volume nor suppress onset of CSDH. Multivariate logistic regression analysis revealed extensive subdural fluid volume as the only risk factor independently associated with CSDH development. CONCLUSIONS: In this study, postoperative large subdural fluid volume represented an independent risk factor associated with the incidence of CSDH after unruptured aneurysmal clipping. Reducing subdural fluid volume strategy could suppress the onset of CSDH after surgery.

Transarterial Embolization of Dural Arteriovenous Fistula in Superior Sagittal Sinus Under Bilateral External Carotid Artery Flow Control: Technical Note.

BACKGROUND: Transarterial embolization (TAE) using liquid embolic material is a standard treatment for non-sinus-type dural arteriovenous fistula (DAVF). However, to reach embolic material over a shunt point for complete obliteration of DAVF is often difficult. We present a technical case report of the efficacy of bilateral external carotid artery (ECA) flow control for the TAE of superior sagittal sinus DAVF. CASE DESCRIPTION: A 64-year-old man presented with dizziness and left hemiparesis. Computed tomography imaging showed right parietal subcortical hemorrhage, and cerebral angiography revealed a DAVF in the superior sagittal sinus fed by bilateral occipital artery, bilateral superficial temporal artery and bilateral middle meningeal artery (MMA), with cortical venous reflux and without connection to the superior sagittal sinus. We therefore planned TAE using glue via MMA under bilateral ECA flow control. A 7-Fr balloon guide catheter was positioned in the bilateral ECA origins, and a microcatheter was introduced distal to the MMA. Heated 20% n-butyl-2-cyanoacrylate was slowly injected via the left MMA under bilateral ECA origin flow control. The n-butyl-2-cyanoacrylate reached the shunt point and obliterated the shunt in a single session. The patient was discharged without neurological symptoms. CONCLUSIONS: Bilateral ECA flow control using balloon guide catheter is safe and effective for a DAVF in the superior sagittal sinus with multiple and tortuous scalp feeders.

Dural Arteriovenous Fistula Arising after Intracranial Surgery in Posterior Fossa of Nondominant Sinus: Two Cases and Literature Review.

The results of recent clinical and experimental studies suggest that the most important factor associated with the pathogenesis of dural arteriovenous fistula (AVF) is sinus thrombosis and subsequent venous or intrasinus hypertension. Here, we describe two patients who each developed a dural AVF after a posterior fossa craniotomy on the side of the nondominant or hypoplastic transverse (TS)-sigmoid (SS) sinuses. A 63-year-old female underwent surgical resection of a meningioma in the left cerebellopontine angle. Preoperative subtraction digital angiography (DSA) revealed a hypoplastic, ipsilateral left TS-SS and the sinus occlusion was revealed after surgery. Sixteen months later, she presented with a progressive left retroauricular, pulse-synchronous bruit. An AVF in the left TS-SS region was diagnosed by DSA and treated with transvenous coil embolization. The patient recovered without neurological deterioration. A 56-year-old female underwent surgical removal of an epidermoid tumor in the right cerebellopontine angle. Preoperative DSA revealed severe, ipsilateral right TS stenosis and the sinus occlusion was revealed after surgery. Two years later, she presented with the progressive right retroauricular, pulse-synchronous bruit, which was diagnosed by DSA as dural AVF in the right TS-SS region. She was treated with transvenous coil embolization and recovered without neurological deterioration. Sinus manipulation during intracranial surgery carries a potential risk of dural AVF development and this should be carefully considered, even when the ipsilateral TS-SS is nondominant or appears hypoplastic.