Introduction An intermediate catheter (IMC) may pose a risk of intraprocedural rupture (IPR) during coil embolization of ruptured intracranial aneurysms (RIAs), because the pressure on the microcatheter and coil might be more direct. To verify this hypothesis, this study explored whether use of an IMC might correlate with an increased rate of IPR during coil embolization for RIAs. Methods We retrospectively reviewed 195 consecutive aneurysms in 192 patients who underwent initial coil embolization for saccular RIAs at our institution between January 2007 and December 2023. Patients were divided into two groups with aneurysms treated either with an IMC (IMC group) or without an IMC (non-IMC group). To investigate whether IMC use increased the rate of IPR, a propensity score-matched analysis was employed to control for age, sex, maximal aneurysm size, neck size, bleb formation, aneurysm location, proximal vessel tortuosity, balloon-assisted coiling, type of microcatheter, and type of framing coil. Results Ultimately, 43 (22%) coil embolization used IMC. In univariate analysis, the incidence of IPR was significantly higher in the IMC group compared with the non-IMC group (14.0 vs. 3.3%, p = 0.016). Propensity score matching was successful for pairs of 26 aneurysms in the IMC group and 52 aneurysms in the non-IMC group. The incidence of IPR was still significantly higher in the IMC group than in the non-IMC group (23.1 vs. 3.8%, p = 0.015). No significant differences in the incidences of ischemic complications and IMC-related parent artery dissection were observed between the two groups. Discussion When using IMC for coil embolization of RIAs, the surgeons should be more careful and delicate in manipulating the microcatheter and inserting the coils to avoid IPR.
We reviewed the clinical outcomes of a procedure that combines endovascular embolization and a direct surgical approach in a hybrid operating room (OR) for the treatment of refractory dural arteriovenous fistulas (dAVFs).All patients with intracranial dAVFs who underwent a procedure combining endovascular embolization and direct surgical approach with biplane angiography or a robotic C-arm system in a hybrid OR between February 2004 and June 2020 were considered. Borden grading, occlusion rate, pre-and post-operative modified Rankin Scale (mRS) scores, and complications were retrospectively investigated. The pre-and postoperative mRS scores were compared using the Wilcoxon signed-ranks test.We evaluated 14 arteriovenous fistulas (AVFs) in consecutive 13 patients. Of these, ten AVFs were previously treated with endovascular embolization, ten were located in the transverse-sigmoid sinus, and four in the cortical vein. The Borden grade was II in two AVFs and III in 12 AVFs. Immediate occlusion of the AVF was achieved in 13 AVFs, and gradual occlusion was observed in one case. The median preoperative mRS was 1 (0-3), whereas the median postoperative mRS was 0 (0-1) which indicated marked improvement (P = 0.006). Complications including postoperative transient visual disturbance and intraprocedural extravasation were observed in only two cases.The combination of endovascular embolization and direct surgical approach in a hybrid OR could achieve sufficient occlusion of refractory AVFs with acceptable complication rates and improved symptoms.
Radial artery diameter may limit whether a guiding sheath (GS) can be used via transradial artery access (TRA). A smaller GS may reduce the risk of access site-related complications. This study investigated the feasibility and safety of endovascular treatment (EVT) using a straight-shaped 3-Fr GS (Axcelguide; Medikit).
Objective: We report a case of severe stenosis at the origin of the persistent primitive proatlantal artery (PPPA) for which a favorable outcome was obtained through stent placement.
To investigate on three-dimensional (3D) fusion images the apposition of low-profile visualized intraluminal support (LVIS) stents in intracranial aneurysms after treatment and assess inter-rater reliability. Records of all patients with unruptured intracranial aneurysms who were treated with the LVIS stent were retrospectively accessed and included in this study. Two neurosurgeons evaluated the presence of malapposition between the vessel walls and the stent trunk (crescent sign) and the vessel wall and the stent edges (edge malappostion) on 3D fusion images. These images were high-resolution cone-beam computed tomography images of the LVIS stent fused with 3D-digital subtraction angiography images of the vessels. Associations between malapposition and aneurysm location were assessed by Fisher's exact test, and inter-rater agreement was estimated using Cohen's kappa statistic. Forty consecutive patients were included. In all patients, 3D fusion imaging successfully visualized the tantalum helical strands and the closed-cell structure of the nitinol material of the low-profile visualized intraluminal support. A crescent sign was observed in 27.5% and edge malapposition in 47.5% of the patients. Malapposition was not significantly associated with location (p=0.23 crescent sign, p=0.07 edge malapposition). Almost perfect (κ=0.88) and substantial (κ=0.76) agreements between the two raters were found for the detection of crescent signs and edge appositions, respectively. 3D fusion imaging provided clear visualization of the LVIS stent and parent arteries, and could detect malapposition with excellent inter-rater reliability. This technique may provide valuable guidance for surgeons in determining postoperative management.
Introduction Although thin‐walled regions (TWRs) in an intracranial aneurysm have a risk of rupture due to contact with surgical instruments, imaging modalities cannot accurately evaluate the thickness of aneurysm walls. The surgical operation will be able to perform safely by identifying the location of TWRs before the treatment. In previous studies, computational fluid dynamics (CFD) has been used to investigate the relationship between hemodynamics and TWRs. However, a quantitative method has not been employed to evaluate the location of TWRs. This study aims to clarify the relationship between hemodynamics and TWRs by comparing the results of CFD analysis with quantitatively defined TWRs. Methods We identified 70 aneurysms (MCA: 48, ACA: 20, ICA: 2) treated with craniotomy and clipping. CFD analysis was conducted to evaluate the pressure difference (PD), wall shear stress (WSS), and wall shear stress divergence (WSSD) on the aneurysm wall. High regions were defined as the regions with values above the 90th percentile for each parameter, and Low regions were defined as the regions with values below the 10th percentile for each parameter. In this study, 4 regions (HighPD, HighWSS, LowWSS, and HighWSSD) and 6 regions obtained by combining two of these regions were defined as regions of interest (RoI). Because TWRs generally indicate intense red, the comprehensive red value (cR value) was defined by using the RGB color model to evaluate the intensity of redness. The cR value was calculated for each pixel of the intraoperative images, and TWRs were defined using the cR value. Comparing the results of CFD analysis and identified TWRs, the percentage of the area of TWRs in RoI was calculated as the occupancy ratio. Results Table 1 shows the mean occupancy ratio for each defined RoI. The mean occupancy ratio in RoI by a single parameter is higher in the order of HighPD, HighWSSD, HighWSS, and LowWSS regions. In HighPD regions, which show the highest occupancy ratio, the impingement flow to the aneurysm wall is considered to make the aneurysm wall thinner. In HighWSSD regions, the aneurysm wall seems to have thinned due to the tensile force along the wall surface caused by blood flow. The mean occupancy ratio of RoI obtained by the combination of two regions is lower than that of HighPD regions. However, in some cases, TWRs that could not be identified by HighPD regions can be detected by HighPD or HighWSSD regions. Conclusions The mean occupancy ratio for RoI was higher in the order of HighPD, HighWSSD, HighWSS, and LowWSS regions. Therefore, it was suggested that these hemodynamic parameters are related to TWRs. Furthermore, in some cases, TWRs that the RoI of a single parameter could not identify can be detected using RoI obtained by the combination of two parameters.
