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In the multimodality treatment of complex brain arteriovenous malformations (AVMs), the role of endovascular embolization is not fully elucidated. To assess the risk of embolization, we retrospectively evaluated the outcomes of endovascular treatment for AVM, focusing on the embolization-related complications.The present study included patients with brain AVM who underwent embolization at our hospital between April 2011 and May 2021. Risk factors for peri- and postoperative complications were analyzed.During the study period, 36 AVMs were treated during 58 embolization sessions. The goal of the embolization was preoperative in 24 (67%), pre-radiosurgical in 9 (25%), and palliative in 3 (8%) cases. The overall complication rate was 43% (25 of 58) per session and 36% (13 of 36) per patient. Ischemic and hemorrhagic complications were observed in 14 (24%) and 14 (24%) cases, respectively. n-Butyl cyanoacrylate (n-BCA) embolization was detected as the significant risk for postoperative hemorrhage in the univariate (79% vs. 36%, P = 0.012; Fisher exact test) and the multivariable analysis (odds ratio 4.90, 95% confidence interval 1.08-22.2, P = 0.039). The number of embolized feeder in a single session also tended to be higher in a hemorrhagic complication group (median 3.5 vs. 2.0, P = 0.11; Mann-Whitney U-test).The risk of embolization in multimodality treatment for complex brain AVM was substantial. n-BCA embolization may carry a higher risk of postoperative hemorrhage. An accumulation of cases is awaited to investigate the effectiveness of minimal target embolization in the future.

BackgroundAlthough endovascular parent artery occlusion (PAO) of the intracranial artery is a well-established treatment option, the long-term stability of cerebral blood flow remains a concern. This study aimed to evaluate the long-term clinical and radiological outcomes of patients who underwent PAO.MethodsThe patients who underwent endovascular PAO of their internal carotid or vertebral artery (VA) between April 2011 and March 2022 were included in this observational study. Information about patient characteristics, details of the endovascular treatment, and clinical and radiological follow-up were collected.ResultsThe study included a total of 104 cases (average age 52.9±12.6 years old, male 73 (70.2%) cases, 95 (91.3%) VA PAO cases) from eight centers. Most cases were performed in an emergency condition, such as ruptured vertebral artery dissecting aneurysm (73 cases [70.2%]). PAO was successful in all cases. Early stroke (within 30 days) occurred in 33 (31.7%) cases (31 cases in VA PAO and two cases in internal carotid PAO) with ischemic stroke (29 cases) comprising the largest group. Clinical follow-up over 12 months was available in 78 cases. During an average follow-up period of 49.5 ± 24.3 months, one case in VA PAO experienced a stroke without functional deterioration. Imaging follow-up was performed in 73 cases. Recanalization of the occluded VA was observed in two cases. The remaining image change was contralateral VA stenosis after VA PAO. The incidence of clinical and radiological events was 0.95 and 1.1% per patient-year, respectively.ConclusionsOnce the patients surpass the acute phase after PAO, their mid-to-long term course was stable. The risk of late stroke or de novo aneurysm formation was lower than expected in the literature, and the direct comparison to novel reconstructiv techniques is warranted in future studies.Registrationhttps://www.umin.ac.jp/ctr/index.html, trial ID: UMIN000045160

We investigated the anatomical characteristics that complicate utilizing the radial artery approach (RAA) for craniocervical intravascular intervention.The data of 73 lesions in 65 consecutive patients who underwent transradial cervical carotid artery intervention was evaluated. We assessed the success rate of RAA in right-sided and left-sided lesions. The diameters and angles of the left and right common carotid arteries and the aortic, brachiocephalic, and right subclavian arteries, which constitute the paths of the guiding sheath, were assessed for each of the left- and right-sided lesions.It was difficult to apply RAA in 10 cases (13.7%), of which 2 (5.0%) involved right-sided and 8 (24.2%) left-sided lesions. The approach was significantly more difficult to perform in left-sided than in right-sided lesions (P = 0.02). Although the treatments were successfully completed, crossover to the femoral artery approach was required in 4 cases (5.5%, 2 cases for left-sided lesions). Placement of the guiding sheath in the common carotid artery was successful for all right-sided lesions; however, the guiding sheath slipped off to the aorta during stent advancement in 2 cases. When the angle between the brachiocephalic artery and aortic arch was small, the introduction of the guiding sheath to left-sided lesions was difficult in eight cases (P = 0.0001).RAA was difficult to perform in cases involving left-sided lesions and a small angle between the brachiocephalic artery and aortic arch. This study could help delineate the factors associated with difficulty of catheter introduction and instability of RAA.

Endovascular revascularization of a chronically occluded internal carotid artery (ICA) is challenging because the occlusive segment can be long and tortuous. A case is presented of a successful recanalization of a chronically occluded ICA by retrograde passing of a guidewire from the intracranial ICA to the cervical ICA via the posterior communicating artery. This case suggests that a retrograde approach for reopening an occluded artery may be useful during neurovascular interventions, similar to percutaneous coronary interventions. In this patient, daily transient ischemic attacks disappeared after successful recanalization of the ICA.

In endoscopic transsphenoidal skull base surgery, knowledge of tumor location on imaging and the anatomic structures is required simultaneously. However, it is often difficult to accurately reconstruct the endoscopic vision of the surgical field from the pre-surgical radiographic images because the lesion remarkably displaces the geography of normal anatomic structures. We created a precise three-dimensional computer graphic model from preoperative radiographic data that was then superimposed on a visual image of the actual surgical field and displayed on a video monitor during endoscopic transsphenoidal surgery. We evaluated the efficacy of this augmented reality (AR) navigation system in 15 consecutive patients with sellar and parasellar tumors. The average score overall was 4.7 [95% confidence interval: 4.58–4.82], which indicates that the AR navigation system was as useful as or more useful than conventional navigation in certain patients. In two patients, AR navigation was assessed as less useful than conventional navigation because perception of the depth of the lesion was more difficult. The developed system was more useful than conventional navigation for facilitating an immediate three-dimensional understanding of the lesion and surrounding structures.

Purpose: To evaluate a new method that registers phase-contrast magnetic resonance angiography images to time-of-flight magnetic resonance angiography images. Methods: Magnetic resonance angiography datasets of 10 healthy volunteers obtained by using two modalities (phase-contrast magnetic resonance angiography and time-of-flight magnetic resonance angiography) were preprocessed. Specifically, vessel regions were extracted using the region growing method with a threshold of 10% of the signal intensity maximum or 50% of the signal intensity maximum for phase-contrast magnetic resonance angiography images and time-of-flight magnetic resonance angiography images, respectively. Then, the normalized mutual information method was used to determine spatial positions, and registration between non-preprocessed phase-contrast magnetic resonance angiography and time-of-flight magnetic resonance angiography was performed using the spatial position information. Misalignment of 3 anatomical points was used to compare the accuracy of registration in this data group (the proposed method group) to that in the data group without registration (the non-registration group) and that in the data group subjected to normalized mutual information-based registration without preprocessing (the non-preprocessing group). Results: The mean misalignment of 3 anatomical points ± standard error was 1.69 ± 0.11 mm in the proposed method group, and 2.77± 0.13 mm and 90.28 ± 8.24 mm in the non-registration group and non-preprocessing group, respectively. The mean misalignment of 3 anatomical points was significantly smaller in the proposed method group than in the non-registration group (p = 0 001). Conclusions: The proposed preprocessing and registration method improved the accuracy of normalized mutual information-based registration between phase-contrast magnetic resonance angiography images and time-of-flight magnetic resonance angiography images.

The natural history of ruptured basilar artery dissecting aneurysms (BADAs) remains unclear compared to that of ruptured vertebral artery dissecting aneurysms (VADAs). In this study, we investigated the natural history and optimal management of ruptured BADAs. We identified 17 patients with ruptured BADA among 4586 patients with aneurysmal subarachnoid hemorrhage (SAH) treated in seven participating hospitals. A scoping literature review was undertaken to investigate prognostic factors. Six patients among the profiled patients (35.3%) died, all with poor SAH grades (World Federation of Neurological Societies Grade IV and V). Rebleeding after admission was observed in three patients (17.6%) with poor SAH grades. Aggressive treatment and conservative management were initiated in seven and ten patients, respectively. Patients with good SAH grades had significantly higher favorable treatment outcomes than those with poor grades (83.3% vs. 9.1%, P = 0.005). Moreover, based on a scoping review of 158 cases with ruptured BADA, including the patients from our series, approximately 90% of patients with good SAH grades had favorable outcomes. A good SAH grade and no rebleeding after admission were favorable prognostic factors (P 0.0001 and P = 0.002, respectively). The rebleeding rates were 20.2%, 13.3%, and 6.3% for dilated, pearl and string, and stenotic lesions, respectively. We concluded that the natural history of isolated ruptured BADAs may be better than that of VADAs. Although definitive treatment, if possible, is undoubtedly important, conservative management with careful radiological follow-up for morphological changes might be a viable option for patients in good clinical condition and with non-dilated lesions.

IntroductionDespite a decade of research into virtual stent deployment and the post-stenting aneurysmal hemodynamics, the hemodynamic factors which correlate with successful treatment remain inconclusive. We aimed to examine the differences in various post-treatment hemodynamic parameters between successfully and unsuccessfully treated cases, and to quantify the additional flow diversion achievable through stent compaction or insertion of a second stent.MethodsA systematic review and meta-analysis were performed on eligible studies published from 2000 to 2019. We first classified cases according to treatment success (aneurysm occlusion) and then calculated the pooled standardized mean differences (SMD) of each available parameter to examine their association with clinical outcomes. Any additional flow diversion arising from the two common strategies for improving the stent wire density was quantified by pooling the results of such studies.ResultsWe found that differences in the aneurysmal inflow rate (SMD −6.05, 95% CI −10.87 to −1.23, p=0.01) and energy loss (SMD −5.28, 95% CI −7.09 to −3.46, pConclusionsInflow rate and energy loss have shown promise as identifiers to discriminate between successful and unsuccessful treatment, pending future research into their diagnostic performance to establish optimal cut-off values.

Background Although the embolization of lenticulostriate artery feeders is often warranted in the treatment of brain arteriovenous malformations, it is technically challenging due to steep and repeated angulations. Here, we describe our novel technique of navigating a flow-guided microcatheter into lenticulostriate artery feeders using the strong support provided by an S-shaped distal access catheter. Methods We reviewed our retrospective cohort of brain arteriovenous malformations, in which lenticulostriate artery feeders were attempted to embolize. Result During the study period, endovascular embolization was performed in 25 arteriovenous malformations cases. Of these, eight lenticulostriate artery feeders were present in six cases (24%). In two cases, lenticulostriate artery feeder catheterization was avoided from the beginning due to the small diameters of the feeders. After all, microcatheter navigation for lenticulostriate artery feeders were attempted in four cases with six lenticulostriate artery feeders. In all the six feeders, the S-shaped distal access catheter was successful in supporting the microcatheter to advance distally to the lenticulostriate artery feeders, even if other approaches were unsuccessful. Of the six catheterized lenticulostriate artery feeders, four were embolized. Symptomatic infarction in the lenticulostriate artery territory and mild vasospasm occurred in two cases each, but they did not result in permanent neurological deficits. Conclusion Although some potential complications need to be considered, the S-shaped distal access catheter technique appears to be an effective alternative approach to gaining access to difficult feeders of arteriovenous malformations.

Background Increasing restrictions over trainees' working hours and the recent coronavirus disease 2019 pandemic warrant new educational methods of surgical skills. We assessed a novel video-recording system for neuroendovascular skill education, developed with the installation of a hybrid operating room (OR) at our institution. Methods A single-plane angiography unit with a large flat display (FlexVision XL; Philips Medical Systems) was installed in our OR. All media sources in the OR, including live fluoroscopy and ceiling-mounted camcorders, were connected to a video switcher. This video switcher laid up to 8 video images into one big image, which was transferred to the large display and the professional-use Blu-ray recorder. The recording was performed continuously during the procedure. This recording system was evaluated retrospectively with a questionnaire administered to the 5 trainees. Results Using this system, 68 interventional procedures were recorded. Among the potential merits, the trainees assigned the greatest value to the simultaneous recording of the operator's hand motions and the fluoroscopy images. Among the potential limitations of the system, the prolonged time and the increased volume of the video data bothered the trainees the most. The recorded video looked like a live demonstration. Conclusions Our “selfie” video recording system was useful for skill training of neuroendovascular interventions.

OBJECTIVEIn Gamma Knife radiosurgery (GKS) for arteriovenous malformations (AVMs), CT angiography (CTA), MRI, and digital subtraction angiography (DSA) are generally used to define the nidus. Although the AVM angioarchitecture can be visualized with superior resolution using rotational angiography (RA), the efficacy of integrating RA into the GKS treatment planning process has not been elucidated.METHODSUsing data collected from 25 consecutive patients with AVMs who were treated with GKS at the authors’ institution, two neurosurgeons independently created treatment plans for each patient before and after RA integration. For all patients, MR angiography, contrasted T1 imaging, CTA, DSA, and RA were performed before treatment. The prescription isodose volume before (PIVB) and after (PIVA) RA integration was measured. For reference purposes, a reference target volume (RTV) for each nidus was determined by two other physicians independent of the planning surgeons, and the RTV covered by the PIV (RTVPIV) was established. The undertreated volume ratio (UVR), overtreated volume ratio (OVR), and Paddick’s conformal index (CI), which were calculated as RTVPIV/RTV, RTVPIV/PIV, and (RTVPIV)2/(RTV × PIV), respectively, were measured by each neurosurgeon before and after RA integration, and the surgeons’ values at each point were averaged. Wilcoxon signed-rank tests were used to compare the values obtained before and after RA integration. The percentage change from before to after RA integration was calculated for the average UVR (%ΔUVRave), OVR (%ΔOVRave), and CI (%ΔCIave) in each patient, as ([value after RA integration]/[value before RA integration] − 1) × 100. The relationships between prior histories and these percentage change values were examined using Wilcoxon signed-rank tests.RESULTSThe average values obtained by the two surgeons for the median UVR, OVR, and CI were 0.854, 0.445, and 0.367 before RA integration and 0.882, 0.478, and 0.463 after RA integration, respectively. All variables significantly improved after compared with before RA integration (UVR, p = 0.009; OVR, p < 0.001; CI, p < 0.001). Prior hemorrhage was significantly associated with larger %ΔOVRave (median 20.8% vs 7.2%; p = 0.023) and %ΔCIave (median 33.9% vs 13.8%; p = 0.014), but not %ΔUVRave (median 4.7% vs 4.0%; p = 0.449).CONCLUSIONSIntegrating RA into GKS treatment planning may permit better dose planning owing to clearer visualization of the nidus and, as such, may reduce undertreatment and waste irradiation. Further studies examining whether the observed RA-related improvement in dose planning also improves the radiosurgical outcome are needed.

The therapeutic effect of carotid endarterectomy (CEA) on visual disturbance caused by chronic ocular ischemia due to carotid artery stenosis has not been validated. This prospective observational study aims to investigate whether CEA is associated with an increase in ocular blood flow (OBF) and postoperative visual improvement. In total, 41 patients with carotid artery stenosis treated by CEA between March 2015 and September 2018 were enrolled in this study. OBF was evaluated by laser speckle flowgraphy, which can measure the mean blur ratio (MBR) which is well correlated to the absolute retinal blood flow. Visual acuity was assessed before and after CEA by subjective improvement and objective visual assessment using CSV-1000, an instrument used to test contrast sensitivity. OBF increased after CEA on the operated side (mean MBR 33.5 vs 38.2, p

Objective Surgical skills are generally acquired by watching the “hand movements” of experts. “Eye movements” are now attracting attention in skill learning fields. Eye-tracking technology was introduced preliminarily to develop a better skill learning system for neuroendovascular treatments. Methods During a task to place a detachable coil into a silastic cerebral aneurysm model under biplane X-ray fluoroscopy, gaze points were recorded using a head-mount eye-tracking device. Results During the task, 91% of fixations were allocated to the monitor displaying fluoroscopic images, and the others to the ha;nds of operators or unspecified visual targets. More than 80% of fixations were located in frontal or lateral fluoroscopic images. Fixations were placed more frequently around the aneurysm than the microcatheter. One operator failed to recognize the timing when the proximal marker of the coil overlapped that of the microcatheter. The subject allocated most fixations to the frontal fluoroscopic image, whereas other subjects put most fixations to the lateral fluoroscopic image. Furthermore, that operator put no fixations to the proximal marker of the microcatheter. Conclusions The results of this preliminary study imply the feasibility of the eye tracking-based learning system for neuroendovascular treatments. The eye-tracking analysis has potential in investigating or preventing procedural failures in neuroendovascular treatments.

Advanced morphology analysis and image-based hemodynamic simulations are increasingly used to assess the rupture risk of intracranial aneurysms (IAs). However, the accuracy of those results strongly depends on the quality of the vessel wall segmentation. To evaluate state-of-the-art segmentation approaches, the Multiple Aneurysms AnaTomy CHallenge (MATCH) was announced. Participants carried out segmentation in three anonymized 3D DSA datasets (left and right anterior, posterior circulation) of a patient harboring five IAs. Qualitative and quantitative inter-group comparisons were carried out with respect to aneurysm volumes and ostia. Further, over- and undersegmentation were evaluated based on highly resolved 2D images. Finally, clinically relevant morphological parameters were calculated. Based on the contributions of 26 participating groups, the findings reveal that no consensus regarding segmentation software or underlying algorithms exists. Qualitative similarity of the aneurysm representations was obtained. However, inter-group differences occurred regarding the luminal surface quality, number of vessel branches considered, aneurysm volumes (up to 20%) and ostium surface areas (up to 30%). Further, a systematic oversegmentation of the 3D surfaces was observed with a difference of approximately 10% to the highly resolved 2D reference image. Particularly, the neck of the ruptured aneurysm was overrepresented by all groups except for one. Finally, morphology parameters (e.g., undulation and non-sphericity) varied up to 25%. MATCH provides an overview of segmentation methodologies for IAs and highlights the variability of surface reconstruction. Further, the study emphasizes the need for careful processing of initial segmentation results for a realistic assessment of clinically relevant morphological parameters.

Objective Skull base meningiomas carry a nonnegligible risk of recurrence. In particular, those arising from the sphenoid wings or middle cranial fossa penetrate into extracranial regions, uncommonly showing massive expansion into the craniofacial regions on recurrence. The role of endoscopic endonasal surgery for those intractable lesions remains unclear. Methods We performed endoscopic endonasal craniofacial surgery for 8 recurrent meningiomas invading into the pterygopalatine fossa, infratemporal fossa, nasopharynx, paranasal sinus, or orbit, comprising 2 meningothelial and 1 fibrous meningiomas (World Health Organization [WHO] grade I), 3 atypical and 1 clear cell meningiomas (grade II), and 1 anaplastic meningioma (grade III). All were large (15–80 cm3; median, 45 cm3) and highly vascularized. Results All 8 tumors were sufficiently resected. Gross total resection of the craniofacial part of the lesions was achieved in 5 patients (62.5%). In 3 patients with WHO grade I meningiomas and 1 with grade II, tumors were successfully controlled as of the last follow-up. In 4 patients with WHO grade II or III meningiomas, craniofacial lesions were controlled, whereas original intracranial lesions were poorly controlled and became critical. Conclusions We consider the endoscopic endonasal approach as an acceptable, less-invasive alternative for recurrent craniofacial meningioma. Although all these cases were relatively large and highly vascularized, preoperative endovascular embolization of the feeding arteries contributes to significantly reducing vascularity of the tumors, and local control of the craniofacial lesions was successfully achieved in all cases. Endoscopic endonasal craniofacial surgery enabled sufficient mass reduction without disfiguring facial incisions.

Purpose—Image-based computational fluid dynamics (CFD) is widely used to predict intracranial aneurysm wall shear stress (WSS), particularly with the goal of improving rupture risk assessment. Nevertheless, concern has been expressed over the variability of predicted WSS and inconsistent associations with rupture. Previous challenges, and studies from individual groups, have focused on individual aspects of the image-based CFD pipeline. The aim of this Challenge was to quantify the total variability of the whole pipeline. Methods—3D rotational angiography image volumes of five middle cerebral artery aneurysms were provided to participants, who were free to choose their segmentation methods boundary conditions, and CFD solver and settings. Participants were asked to fill out a questionnaire about their solution strategies and experience with aneurysm CFD, and provide surface distributions of WSS magnitude, from which we objectively derived a variety of hemodynamic parameters. Results—A total of 28 datasets were submitted, from 26 teams with varying levels of self-assessed experience. Wide variability of segmentations, CFD model extents, and inflow rates resulted in interquartile ranges of sac average WSS up to 56%, which reduced to < 30% after normalizing by parent artery WSS. Sac-maximum WSS and low shear area were more variable, while rank-ordering of cases by low or high shear showed only modest consensus among teams. Experience was not a significant predictor of variability. Conclusions—Wide variability exists in the prediction of intracranial aneurysm WSS. While segmentation and CFD solver techniques may be difficult to standardize across groups, our findings suggest that some of the variability in image-based CFD could be reduced by establishing guidelines for model extents, inflow rates, and blood properties, and by encouraging the reporting of normalized hemodynamic parameters. Fil: Valen-Sendstad, Kristian. Simula Research Laboratory and Center for Cardiological Innovation; Noruega Fil: Bergersen, Aslak W.. University of Oslo; Noruega Fil: Shimogonya, Yuji. Nihon University; Japón Fil: Goubergrits, Leonid. Charite´ – Universita¨tsmedizin Berlin; Alemania Fil: Bruening, Jan. Charité – Universitätsmedizin Berlin; Alemania Fil: Pallares, Jordi. Universitat Rovira I Virgili; España Fil: Cito, Salvatore. Universitat Rovira I Virgili; España Fil: Piskin, Senol. University Of Texas At San Antonio.; Estados Unidos Fil: Pekkan, Kerem. Koc University; Turquía Fil: Geers, Arjan J.. Universitat Pompeu Fabra; España Fil: Larrabide, Ignacio. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Grupo de Plasmas Densos Magnetizados. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Grupo de Plasmas Densos Magnetizados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rapaka, Saikiran. Siemens Medical Solutions USA Inc; Estados Unidos Fil: Mihalef, Viorel. Siemens Medical Solutions USA Inc; Estados Unidos Fil: Fu, Wenyu. Beijing Union University; China Fil: Qiao, Aike. Beijing University of Technology; China Fil: Jain, Kartik. Simula Research Laboratory and Center for Cardiological Innovation; Noruega. University of Siegen; Alemania. University of Zürich; Suiza Fil: Roller, Sabine. University of Siegen; Alemania Fil: Mardal, Kent-Andre. Simula Research Laboratory and Center for Cardiological Innovation; Noruega. University of Oslo; Noruega Fil: Kamakoti, Ramji. Dassault Systemes; Francia Fil: Spirka, Thomas. Simpleware Software Solutions; Reino Unido Fil: Ashton, Neil. University of Oxford; Reino Unido Fil: Revell, Alistair. University of Manchester; Reino Unido Fil: Aristokleous, Nicolas. University of Limerick; Irlanda Fil: Houston, J. Graeme. University of Dundee; Reino Unido Fil: Tsuji, Masanori. Mie Chuo Medical Center; Japón Fil: Ishida, Fujimaro. Mie Chuo Medical Center; Japón Fil: Menon, Prahlad G.. University of Pittsburgh; Estados Unidos Fil: Browne, Leonard D.. University of Limerick; Irlanda Fil: Broderick, Stephen. University of Limerick; Irlanda Fil: Shojima, Masaaki. University of Tokyo; Japón Fil: Koizumi, Satoshi. University of Tokyo; Japón Fil: Barbour, Michael. University of Washington; Estados Unidos Fil: Aliseda, Alberto. University of Washington; Estados Unidos Fil: Morales, Hernán G.. Medisys - Philips Research Paris; Francia Fil: Lefèvre, Thierry. Medisys - Philips Research Paris; Francia Fil: Hodis, Simona. Texas A&M University - Kingsville; Estados Unidos Fil: Al-Smadi, Yahia M.. Jordan University of Science and Technology; Jordania Fil: Tran, Justin S.. Stanford University; Estados Unidos Fil: Marsden, Alison L.. Stanford University; Estados Unidos Fil: Vaippummadhom, Sreeja. EinNel Technlogies; India Fil: Einstein, G. Albert. EinNel Technlogies; India Fil: Brown, Alistair G.. Siemens PLM Software; Estados Unidos Fil: Debus, Kristian. Siemens PLM Software; Estados Unidos Fil: Niizuma, Kuniyasu. Tohoku University; Japón Fil: Rashad, Sherif. Tohoku University; Japón Fil: Sugiyama, Shin-ichiro. Kohnan Hospital; Japón Fil: Owais Khan, M.. University of Toronto; Canadá Fil: Updegrove, Adam R.. University of California at Berkeley; Estados Unidos Fil: Shadden, Shawn C.. University of California at Berkeley; Estados Unidos Fil: Cornelissen, Bart M. W.. Academic Medical Center; Países Bajos Fil: Majoie, Charles B. L. M.. Academic Medical Center; Países Bajos Fil: Berg, Philipp. University of Magdeburg; Alemania Fil: Saalfield, Sylvia. University of Magdeburg; Alemania Fil: Kono, Kenichi. Wakayama Rosai Hospital; Japón Fil: Steinman, David A.. University of Toronto; Canadá

Background Stereotactic radiosurgery (SRS) is generally considered a minimally invasive treatment modality. However, definitive evidence of the efficacy of SRS in the elderly population is still not available. Methods The outcomes of 561 elderly and nonelderly patients who underwent SRS for AVM at our institution between 1990 and 2013 were reviewed, analyzed, and compared. Elderly patients were defined as those age ≥60 years at the time of SRS. Results The elderly cohort comprised 55 patients; the nonelderly cohort, 506. In the elderly cohort, the median age was 65 years, and the duration of follow-up was 91 months. The actuarial obliteration rates were 47% at 3 years, 70% at 4 years, and 76% at 5 years in the elderly cohort, and 57% at 3 years, 76% at 4 years, and 83% at 5 years in the nonelderly cohort. In the elderly cohort, the hemorrhage rates during the post-SRS latent phase were 5.2%/year in patients with hemorrhagic onset and 0%/year in those with nonhemorrhagic onset, and event-free survival (EFS) was 93% at 6 years and 89% at 12 years. The obliteration rate, mortality, and EFS rate were not significantly different between the 2 cohorts, whereas the rate of perifocal edema was significantly lower (P = 0.021) in the elderly cohort. The pre-SRS and post-SRS hemorrhage rates were slightly higher in the elderly cohort, albeit without statistical significance. Conclusions Therapeutic effects and outcomes of SRS are similar in elderly and nonelderly patients. Treatment-related neurologic deficits are rare, and longer EFS can be expected.

Background The universal application of ultra-early surgery for World Federation of Neurological Societies (WFNS) grade V aneurysmal subarachnoid hemorrhage (aSAH) patients may lead to the increased implementation of unnecessary treatment. Therefore, this study aimed to refine the patient selection process for timely definitive treatment. Methods From January 2011 to March 2020, a total of 517 aSAH patients were treated at our institution. Among these, 177 aSAH patients with WFNS grade V on admission were identified from our database. Patients with improved grades in response to the initial supportive treatment, with clinical or radiological signs of herniation, and with irreversible signs of brain damage such as bilaterally dilated pupils and global ischemia on follow-up CT scan were excluded. The outcome of definitive treatment for 54 patients without herniation who remained with WFNS grade V after the initial supportive treatment were analyzed to seek any factor for a favorable outcome (modified Rankin scale 0–2). Results Among 54 patients, 19 (35.2%) had a favorable outcome after a definitive treatment. Multivariate logistic regression analysis showed that the best motor response (BMR) 4 on Glasgow Coma Scale was significantly associated with favorable outcomes (odds ratio, 3.76; 95% confidence interval, 1.09–13.0, p = 0.03). The positive predictive value of BMR 4 was 48.3%. Conclusions Albeit being simple, BMR 4 may facilitate the prompt aggressive treatment for patients with WFNS grade V including those with “true” grade V who do not have any clinical and radiological signs of herniation.

Spinal extradural arteriovenous fistulas (AVFs) may be more difficult to prospectively identify than dural AVFs because they are less common than dural AVFs. The primary purpose was to further characterize the diagnostic imaging of spinal extradural AVFs with intradural retrograde venous drainage. The magnetic resonance (MR) imaging and angiographic results of 23 patients with suspected spinal dural AVFs were analyzed in order to distinguish dural and extradural AVFs. The diagnostic accuracy of MR angiography was retrospectively compared between dural and extradural AVFs. All 23 patients showed high intensity in the spinal cord on T2-weighted MR images. Eighteen out of 23 patients were diagnosed with dural AVFs, while the remaining 5 were diagnosed with extradural AVFs by angiography. Extradural AVFs were fed by a branch of the segmental artery to the vertebral body, characterized by a fistula located in the ventral extradural space, and drained retrogradely via an epidural venous pouch into intradural veins. The segmental artery was localized within 1 vertebral level using MRA in 12 out of 18 patients (67%) with dural AVFs and in 1 out of 5 patients (20%) with extradural AVFs (p=0.09). The reasons behind the lower accuracy was mainly the image misinterpretation. Congestion of the spinal cord in spinal extradural AVFs with intradural retrograde venous drainage was similar to that in dural AVFs, whereas its angioarchitecture differed from that of dural AVFs. A clearer understanding of the imaging features of extradural AVFs is important for improving the diagnostic accuracy and clarifying treatment targets.

Background Multiple cerebral aneurysms are encountered in approximately 15% to 35% of patients harboring unruptured cerebral aneurysms. It would be of clinical value to determine which of them is most likely to rupture. Objective To characterize features of the ruptured aneurysm relative to other concomitant fellow aneurysms in patients with multiple cerebral aneurysms. Methods From a total of 5720 patients who were prospectively registered in the Unruptured Cerebral Aneurysm Study in Japan, a subgroup of patients with multiple cerebral aneurysms who developed subarachnoid hemorrhage was extracted for this post hoc analysis. Intrapatient comparisons of each aneurysm were carried out using aneurysm-specific factors such as size, location, and shape to identify predictors of rupture among the fellow aneurysms in a patient with multiple cerebral aneurysms. Results Twenty-five patients with 62 aneurysms were identified from the total cohort of 5720 patients. With the distinctiveness in size, which means the aneurysm was the single largest among the multiple aneurysms, the ruptured aneurysm in each case was discriminated from the other coexisting aneurysms with a sensitivity of 0.76 and specificity of 0.86. Conclusion Our results suggest that the largest aneurysm is likely to rupture among coexisting aneurysms in a patient with multiple cerebral aneurysms.

Oral pyogenic granuloma, also known as lobular capillary hemangioma, is a common benign lesion in the oral cavity. Although the etiopathogenesis of oral pyogenic granuloma remains to be determined, it is speculated to be one of the inflammatory hyperplasias that arise in response to stimuli such as traumatic injury or hormonal factors. We recently experienced a gingival lesion in a 49-year-old female that presented diagnostic difficulties and was finally diagnosed as an oral pyogenic granuloma. The lesion had been initially suspected to be a malignant tumor or arteriovenous malformation because of severe bone resorption of the maxilla or its throbbing. Due to the hypervascularization of this lesion, transarterial embolization was carried out, followed by surgical excision. Pyogenic granuloma with bone resorption is quite rare and to the best of our knowledge has never been reported with extensive maxillary bone resorption penetrating the maxillary sinus. With regard to possible etiologies of this lesion, chronic stimulation by unstable tooth root that was bridged to adjacent teeth and/or a hormonal imbalance caused by progestin, which the patient has taken for many years for the treatment of endometriosis were suspected to be involved.

Background: The wall-to-lumen ratio (WLR) is an important parameter in vascular medicine because it indicates the character of vascular wall as well as the degree of stenosis. Despite the advances in medical imaging technologies, it is still difficult to measure the thin-walled normal intracranial arteries, and the reports on the WLR of normal intracranial artery are limited. It might be possible to calculate the WLR using the indocyanine green (ICG) angiography, which is used to observe intracranial vessels during microsurgery. Purpose: To evaluate the WLR of normal intracranial arteries using ICG angiography. Materials and Methods: From the three cases in which ICG angiography was recorded with a ruler during microsurgery, 20 measurement points were chosen for the analysis. The ICG was injected intravenously with a dose of 0.2 mg/kg, and the vessels were inspected at high magnification using an operating microscope equipped with near-infrared illumination system. The vessel outer diameter and the luminal diameter were measured using the images before and after the ICG arrival based on the pixel ratio method using a ruler as reference, respectively. The WLR was calculated as 0.5 × (vessel outer diameter − vessel luminal diameter). Results: The WLR (mean ± standard deviation) of normal intracranial arteries was 0.086 ± 0.022. The WLR tended to be high in small arteries. Conclusion: The WLR of normal intracranial arteries calculated using ICG angiography was consistent with the WLR reported in the previous reports based on human autopsy.

In order to grasp the spatial and temporal evolution of vascular geometry, three-dimensional (3D) arterial bending structure and geometrical changes of arteries and stent grafts (SG) must be quantified using geometrical parameters such as curvature and torsion along the vasculature centerlines extracted from medical images. Here, we develop a robust method for constructing smooth centerlines based on a spline fitting method (SFM) such that the optimized geometric parameters of curvature and torsion can be obtained independently of digitization noise in the images. Conventional SFM consists of the 3rd degree spline basis function and 2nd derivative penalty term. In contrast, the present SFM uses the 5th degree spline basis function and 3rd and 4th derivative penalty terms, the coefficients of which are derived by the Akaike information criterion. The results show that the developed SFM can reduce the errors of curvature and torsion compared to conventional SFM. We then apply the present SFM to the centerline of the SG in an abdominal aortic aneurysm (AAA), and those of bilateral internal carotid arteries (ICA) in 6 cases: 3 cases with aneurysms and 3 cases without any aneurysm. The SG centerlines were obtained from temporal medical images at three scan times. The strong peak of the curvature could be clearly observed in the distal area of the SG, the inversion of the torsion at 0 months in the middle area of SG disappeared over time, and the torsions around the SG bifurcation at the three time periods were inverted. The curvature-torsion graphs along the ICA centerlines superimposing five aneurysmal positions were useful for investigating the relationship between arterial bending structure and aneurysmal positions. Both ICAs had curvature peak values higher than 0.4 within the ICA syphons. The ICA torsion graphs indicated that left and right ICA tended to be a right- and left-handed helix, respectively. In the left ICA syphon, the biggest aneurysm could be observed downstream of the salient torsion inversion. All aneurysms for 3 cases were positioned at the downstream of the inverted torsion.

Background Vertebral artery injuries (VAIs) caused by cervical trauma include irregularities with narrowing of the arterial wall, dissection, pseudoaneurysm formation, occlusion, and transection. Although recent guidelines have recommended anticoagulant or antiplatelet therapy to prevent subsequent stroke in patients with traumatic VAIs, regardless of the type of vascular injury, the clinical role of endovascular surgery in the treatment of traumatic VAIs remains to be elucidated. Methods We retrospectively evaluated the treatment outcomes of 23 patients with cervical fracture and vertebral artery occlusion (VAO) who had required cervical surgery in the acute stage. Results No patient received antiplatelet or anticoagulant therapy, because the VAs had already become occluded. After cervical surgery, 5 of the 23 patients developed radiologically confirmed thromboembolic stroke after cervical surgery. None of these 5 patients with postoperative infarction had undergone preoperative VA embolization. Univariate analysis revealed that only the implementation of preoperative VA embolization was associated with the prevention of postoperative infarction (P = 0.004). Factors such as age, reduction, level of VAO, and diabetes mellitus did not correlate with increased risk. Conclusions The clinical role of endovascular surgery for traumatic VAI has not been previously established; however, a more specific selection of patients according to the VAI type might be necessary. Our data have indicated that preoperative embolization of the occluded VA significantly reduces the risk of postoperative infarction in a specific cohort of patients with traumatic VAI (i.e., patients with post-traumatic VAO who require cervical surgery).