Neurovascular Imaging with Ultra-High-Resolution Photon-Counting CT: Preliminary Findings on Image-Quality Evaluation.

BACKGROUND AND PURPOSE: The first-generation photon-counting detector CT was recently introduced into clinical practice and represents a promising innovation in high-resolution CT imaging. The purpose of this study was to assess the image quality of ultra-high-resolution photon-counting detector CT compared with energy-integrating detector CT and to explore different reconstruction kernel sharpness levels for the evaluation of intracranial aneurysms. MATERIALS AND METHODS: Ten patients with intracranial saccular aneurysms who had previously undergone conventional energy-integrating detector CT were prospectively enrolled. CT angiograms were acquired on a clinical dual-source photon-counting detector CT in ultra-high-resolution mode and reconstructed with 4 vascular kernels (Bv36, Bv40, Bv44, Bv48). Quantitative and qualitative image-quality parameters of the intracranial arteries were evaluated. For the quantitative analysis (image noise, SNR, contrast-to-noise ratio), ROIs were manually placed at standard anatomic intracranial and extracranial locations by 1 author. In addition, vessel border sharpness was evaluated quantitatively. For the qualitative analysis, 3 blinded neuroradiologists rated photon-counting detector CT and energy-integrating detector CT image quality for the evaluation of the intracranial vessels (ie, the aneurysms and 9 standard vascular branching locations) on a 5-point Likert-type scale. Additionally, readers independently selected their preferred kernel among the 4 kernels evaluated on photon-counting detector CT. RESULTS: In terms of quantitative image quality, Bv48, the sharpest kernel, yielded increased image noise and decreased SNR and contrast-to-noise ratio parameters compared with Bv36, the smoothest kernel. Compared with energy-integrating detector CT, the Bv48 kernel offered better quantitative image quality for the evaluation of small intracranial vessels (P < .001). Image-quality ratings of the Bv48 were superior to those of the energy-integrating detector CT and not significantly different from ratings of the B44 reconstruction kernel. When comparing side by side all 4 photon-counting detector reconstruction kernels, readers selected the B48 kernel as the best to visualize the aneurysms in 80% of cases. CONCLUSIONS: Ultra-high-resolution photon-counting detector CT provides improved image quality for neurovascular imaging. Although the less sharp kernels provided superior SNR and contrast-to-noise ratio, the sharpest kernels delivered the best subjective image quality on photon-counting detector CT for the evaluation of intracranial aneurysms.

Task-based selection of three-dimensional rotational angiography imaging modes using in-house phantom.

INTRODUCTION: The presence of two modes of three-dimensional rotational angiography (3DRA), both intended for cranial applications with similar protocol names ('cerebral' and 'head limited' with no explanation on what the phrase 'limited' represent), had caused some degree of difficulty with the clinicians and radiographers on deciding which mode to select for which task. This study was aimed to use an in-house phantom to assist with this clinical issue of 3DRA usage in terms of mode selection. METHODS: An in-house phantom was used in this study to further analyze and recommend selection. A variety of iodinated contrast agent (ICA) concentrations in the objects were used to simulate clinical images of cranial vessels. The Kerma-area product (KAP) was used as dose metric, while the signal difference to noise ratio (SDNR) of the artificial vessels was employed to represent image quality in terms of contrast. The x-ray spectrum analysis was performed for quantitative evaluation. RESULTS: The non-standard 'head limited' mode is more suggestible for use. Additionally, the 'low' detail option provides the lowest KAP (due to low tube loading) but provided slightly higher SDNR compared to those from 'normal' detail option. A minimum concentration of 18.5 mg/ml of iodine is required to obtain the comparable SDNR with those of higher concentration when the 'low' detail option is selected. CONCLUSION: The 'head limited' mode with 'low' detail options is advisable for contrast-enhanced procedures. To ensure proper use of each mode, effective collaboration should be established between clinical users, medical physicists, and manufacturer's technical representatives. IMPLICATIONS FOR PRACTICE: Selection modes for 3DRA procedures have been made less subjective, following dose and image quality of each mode. Future issues can be addressed by collaborating with medical physicists.

Open surgery retrieval of a missing guidewire causing cerebral infarctions after cerebral angiography: a case report.

BACKGROUND: Intra-aortic foreign body (IAFB) is uncommon, which is usually caused by a rupture of the catheter or guidewire. IAFB can cause catastrophic complications, including arrhythmia, embolization of guidewire fragments, intravascular clipping of the guidewire and vascular perforation. However, there are still no guidelines on removal and management of IAFB. Here, we present a rare case of fractured cerebral angiographic guidewires in the aorta that resulted in multiple cerebral infarctions. CASE PRESENTATION: A 50-year-old man experienced new cerebral infarction after cerebral angiography. Computed tomography and echocardiography demonstrated foreign bodies in his ascending aorta and aortic arch. Open surgery was successfully performed to retrieve the guidewires. The postoperation and follow-up was uneventful. CONCLUSION: It is very important for interventional radiologists to check the catheter and guidewire after operation and perform ultrasound or radiograph to prevent IAFB. Additionally, the effective management of IAFB requires the early detection and the selection of appropriate treatment options, as well as long-time follow up.

Performance of Radiomics derived morphological features for prediction of aneurysm rupture status.

BACKGROUND: Morphological differences between ruptured and unruptured cerebral aneurysms represent a focus of neuroimaging researchfor understanding the mechanisms of aneurysmal rupture. We evaluated the performance of Radiomics derived morphological features, recently proposed for rupture status classification, against automatically measured shape and size features previously established in the literature. METHODS: 353 aneurysms (123 ruptured) from three-dimensional rotational catheter angiography (3DRA) datasets were analyzed. Based on a literature review, 13 Radiomics and 13 established morphological descriptors were automatically extracted per aneurysm, and evaluated for rupture status prediction using univariate and multivariate statistical analysis, yielding an area under the curve (AUC) metric of the receiver operating characteristic. RESULTS: Validation of overlapping descriptors for size/volume using both methods were highly correlated (p<0.0001, R 2=0.99). Univariate analysis selected AspectRatio (p<0.0001, AUC=0.75), Non-sphericity Index (p<0.0001, AUC=0.75), Height/Width (p<0.0001, AUC=0.73), and SizeRatio (p<0.0001, AUC=0.73) as best among established descriptors, and Elongation (p<0.0001, AUC=0.71) and Flatness (p<0.0001, AUC=0.72) among Radiomics features. Radiomics Elongation correlated best with established Height/Width (R 2=0.52), whereas Radiomics Flatness correlated best with Ellipticity Index (R 2=0.54). Radiomics Sphericity correlated best with Undulation Index (R 2=0.65). Best Radiomics performers, Elongation and Flatness, were highly correlated descriptors (p<0.0001, R 2=0.75). In multivariate analysis, established descriptors (Height/Width, SizeRatio, Ellipticity Index; AUC=0.79) outperformed Radiomics features (Elongation, Maximum3Ddiameter; AUC=0.75). CONCLUSION: Although recently introduced Radiomics analysis for aneurysm shape and size evaluation has the advantage of being an efficient operator independent methodology, it currently offers inferior rupture status discriminant performance compared with established descriptors. Future research is needed to extend the current Radiomics feature set to better capture aneurysm shape information.

Application of pigtail catheter tailing combined with long-wire swapping technique in cerebral angiography via the right radial artery.

The safety and feasibility of transradial approach for cerebral angiography has been confirmed previously. However, this approach has been limited used due to the difficulty during the procedure. This study aimed to introduce a pigtail catheter tailing and long-wire swapping technique to improve the success rate without increasing complications.From August 2015 to December 2018, 560 patients who underwent cerebral angiography via transradial approach were recruited. The data including the type of aortic arch, type of Simmon catheter were collected.The loop was successfully constructed in 553 patients using Simmon-2 or Simmon-1 catheter. Of these patients, 72 patients successfully underwent cerebral and renal angiography, while 481 patients underwent cerebral angiography. The time for angiography was 52.87 ±â€Š11.23 minutes and 47.8 ±â€Š11.8 minutes, respectively. There were 369 (66.7%), 135 (24.4%), and 49 (8.9%) patients with type I, type II, and type III aortic arches, respectively, and their success rates of looping using Simmon-2 catheter were 97.8%, 97.0%, and 89.8%, respectively. The success rates of angiography in the right internal carotid artery, right vertebral artery, left internal carotid artery, and left vertebral artery were 100%, 100%, 98.9%, and 98.9%, respectively. No serious complications were observed in all patients.The pigtail catheter tailing and long guidewire swapping is considered as a safe procedure with high success rate for loop construction using a Simmon-2 catheter through the right radial artery, subsequently improving the success rate as well as the efficiency of angiography.

Evaluation of the anastomoses between the ophthalmic artery and the middle meningeal artery by superselective angiography.

PURPOSE: There are three anastomoses between the ophthalmic artery (OA) and the middle meningeal artery (MMA): the anastomotic branch with MMA, the recurrent meningeal branch and the anterior falx artery. We aimed to evaluate the anastomotic branches between the OA and the MMA on superselective angiograms of pediatric patients with retinoblastoma. MATERIALS AND METHODS: We evaluated 126 angiographies performed on children with retinoblastoma. The mean diameter and angiographic visibility percentage of the anastomotic branches between the OA and the MMA were examined according to age group and sex. RESULTS: The mean diameter of anastomotic branch with MMA was measured 0.58 ± 0.13 mm and we found this branch in 15 of 126 angiographic images (11.9%). We detected the recurrent meningeal branch in 47 of total images (37.3%). The recurrent meningeal branch arose 85.1% from the lacrimal artery, 8.5% from the anastomotic branch with MMA and 6.4% directly from the OA. The mean diameter of this artery was measured 0.21 ± 0.06 mm. Anterior falx artery was found in 86 of 126 angiographic peocedures (68.3%) and the mean diameter was measured 0.22 ± 0.06 mm. CONCLUSION: Knowledge of the anastomoses between the OA and the MMA system are all necessary to perform safe and successful endovascular and surgical procedures involving the orbital region.

Endovascular robotic: feasibility and proof of principle for diagnostic cerebral angiography and carotid artery stenting.

BACKGROUND: Robots in surgery aid in performing delicate, precise maneuvers that humans, with inherent physical abilities, may be limited to perform. The CorPath 200 system is FDA approved and is being implemented in the US for interventional cardiology procedures. CorPath GRX robotic-assisted platform is the next-generation successor of CorPath 200. OBJECTIVE: To discuss the feasibility and early experience with the use of the CorPath GRX robotic-assisted platform for neuroendovascular procedures, including transradial diagnostic cerebral angiograms and transradial carotid artery stenting. METHODS: The cases of 10 consecutive patients who underwent neuroendovascular robotic-assisted procedures between December 1, 2019 and December 30, 2019, are presented. RESULTS: Seven patients underwent elective diagnostic cerebral angiography, and three patients underwent carotid artery angioplasty and stenting using the CorPath GRX robotic-assisted platform. All procedures were performed successfully, and no complications were encountered. Conversion to manual control occurred in three diagnostic cases because of a bovine arch that was previously not known. The fluoroscopy time and the procedure time continued to improve with subsequent procedures as we streamlined the workflow. CONCLUSION: This series demonstrates the early use of this technology. It could potentially be used in the near future for acute stroke interventions in remote geographic locations and in places where a neurointerventionalist is not available.

Novel Technique for Detection of Actual Position of Clot During Endovascular Clot Retrieval: Assessment of Microcatheter Withdrawing Angiography.

BACKGROUND: When endovascular clot retrievals are performed using a stent retriever and/or an aspiration catheter, identifying the accurate position of a clot is extremely important for a successful immediate recanalization. Herein, we report a new technique called microcatheter withdrawing angiography, which facilitates the identification of the precise position of a clot. The negative shadow appearance of the clot on angiography was referred to as the actual crab claw sign. METHODS: When a 0.027-inch microcatheter penetrated the clot after inserting a 0.014-inch microwire, selective angiography was conducted using the microcatheter. Simultaneously, the microcatheter was slowly withdrawn with continuous contrast media injection, while the microwire was kept in the distal vessel. The precise position of the clot was found, which was referred to as the actual crab claw sign. Next, we conducted in vitro and in vivo analyses. RESULTS: The actual crab claw sign could be identified in the vascular model and in actual clinical settings. Therefore the sweet spot of the stent retriever could be set over the clot, and an accurate contact aspiration could be performed using an aspirator. CONCLUSIONS: Microcatheter withdrawing angiography can help identify the actual crab claw sign. This technique has a higher success rate and faster recanalization than conventional strategy, particularly in challenging cases of unsuccessful recanalization during the first attempt.

Initial Experience with Exoscopic-Based Intraoperative Indocyanine Green Fluorescence Video Angiography in Cerebrovascular Surgery: A Preliminary Case Series Showing Feasibility, Safety, and Next-Generation Handheld Form-Factor.

BACKGROUND: Native vessel patency and residual lesion are primary sources of morbidity in cerebrovascular surgery (CVS) that require real-time visualization to inform surgical judgment, as is available in endovascular procedures. Micro Doppler and microscopy-based indocyanine green (ICG) fluorescence are promising evolutions compared with intraoperative angiography (IA), and digital subtraction angiography (DSA) remains the gold standard. Exoscopic visualization in CVS is emerging; however, the feasibility of exoscopic-based ICG (ICG-E) for CVS has not yet been reported. To objective of the study was to provide initial experience with ICG-E video angiography in CVS. METHODS: Retrospective study in which 2 ICG-E form-factors (exoscopic-coupled or self-contained handheld imager) were used to determine native vessel patency and residual and compared with DSA. RESULTS: Eleven patients (8 aneurysms, 3 arteriovenous malformations [AVMs]) were included. ICG-E was feasible in all, providing real-time information leading to operative decisions affecting surgical judgment. For aneurysms, discordance of IA with ICG-E and DSA was 12%. In 1 patient, IA showed non-flow-restrictive branch stenosis; however, both ICG and DSA showed patency. All AVMs were fully obliterated, with 100% concordance among all modalities. ICG averaged 4.2 mg dose/run (1-4 doses/case); 1.25 mg was the lowest dose allowing visualization with no advantage with escalating dosages. There were no intraoperative/perioperative complications. CONCLUSIONS: In this preliminary study, ICG-E was safe and feasible, providing real-time visualization informing surgical decision making. The last 4 cases (2 aneurysms and 2 AVMs) evolved toward a portable handheld device, a readily accessible real-time modality providing contextual anatomic and flow visualization. Larger studies are needed to assess broader safety, dose escalation, and efficacy.

Microcatheter shaping using three-dimensional printed models for intracranial aneurysm coiling.

BACKGROUND AND PURPOSE: Microcatheterization is an important, but also difficult, technique used for the embolization of intracranial aneurysms. The purpose of this study was to investigate the application of three-dimensional (3D) printing technology in microcatheter shaping. METHODS: Nine cases of internal carotid artery posterior communicating artery aneurysm diagnosed by CT angiography were selected, and 3D printing technology was used to build a 3D model including the aneurysm and the parent artery. The hollow and translucent model had certain flexibility; it was immersed in water and the microcatheter was introduced into the water to the target position in the aneurysm, followed by heating the water temperature to 50°C. After soaking for 5 min, the microcatheter was taken out and the shaping was completed. After sterilization, the shaped microcatheter was used for arterial aneurysm embolization and evaluation was conducted. RESULTS: Nine cases of microcatheter shaping were satisfactory and shaping the needle was not necessary; no rebound was observed. The microcatheter was placed in an ideal position, and the stent-assisted method was used in three cases of wide-neck aneurysm. There were no complications related to surgery. CONCLUSION: A new microcatheter shaping method using 3D printing technology makes intracranial artery aneurysm embolization more stable and efficient.

Contemporary and emerging magnetic resonance imaging methods for evaluation of moyamoya disease.

Numerous recent technological advances offer the potential to substantially enhance the MRI evaluation of moyamoya disease (MMD). These include high-resolution volumetric imaging, high-resolution vessel wall characterization, improved cerebral angiographic and perfusion techniques, high-field imaging, fast scanning methods, and artificial intelligence. This review discusses the current state-of-the-art MRI applications in these realms, emphasizing key imaging findings, clinical utility, and areas that will benefit from further investigation. Although these techniques may apply to imaging of a wide array of neurovascular or other neurological conditions, consideration of their application to MMD is useful given the comprehensive multidimensional MRI assessment used to evaluate MMD. These MRI techniques span from basic cross-sectional to advanced functional sequences, both qualitative and quantitative.The aim of this review was to provide a comprehensive summary and analysis of current key relevant literature of advanced MRI techniques for the evaluation of MMD with image-rich case examples. These imaging methods can aid clinical characterization, help direct treatment, assist in the evaluation of treatment response, and potentially improve the understanding of the pathophysiology of MMD.

Usefulness of a New Electronic Conductivity Device with a Pedicle Probe and a Multi-axis Angiography Unit for Inserting a C1 Lateral Mass Screw Safely and Tightly: A Technical Note.

The C1 lateral mass screw (LMS) is widely used as one of the screws for atlantoaxial fixation. Tight bicortical screwing from the posterior to anterior cortical margin of the atlas is recommended. However, important structures, such as the internal carotid artery, are located around this area so precision is required to avoid injuring them. We describe the usefulness of a new electronic conductivity device (ECD) with a pedicle probe and a multi-axis angiography unit for inserting the C1 LMS. Four consecutive patients who were treated with C1 and C2 posterior fixation using an ECD and a multi-axis angiography unit in the hybrid operating room were included. All patients were treated successfully. Seven of eight bicortical screws could be inserted into the perfectly ideal location. The median (interquartile range) distance from the anterior margin of the atlas to the tip of the screw was 0.81 mm (0.43, 1.21 mm). This study suggested that the ECD and multi-axis angiography unit are useful for inserting the C1 LMS safely and tightly.

Double stent assisted coiling of intracranial bifurcation aneurysms in Y and X configurations with the Neuroform ATLAS stent: immediate and mid term angiographic and clinical follow-up.

PURPOSE: Self-expandable stents have broadened the spectrum of endovascular treatment of intracranial aneurysms. However, procedures involving double stenting in Y/X configurations carry a relatively high risk of procedural complications. The Neuroform ATLAS, the evolution of Neuroform EZ, is a nitinol self-expanding hybrid/open cell stent which can be delivered through a low profile 0.017 inch catheter. We present our experience in the treatment of intracranial aneurysms with this stent in Y and X configurations. MATERIALS AND METHODS: We prospectively maintained a database from consecutive patients who underwent double stent assisted coiling with the Neuroform ATLAS, from July 2015 to February 2019. Clinical and angiographic results were analyzed. RESULTS: 55 patients harboring 55 bifurcation aneurysms were treated with double stenting: 52 'Y' configurations, 3 'X' configurations. Deployment was successful in all cases. Post-treatment control angiography showed complete occlusion in 33 cases (60%), neck remnant in 8 cases (14.5%), and incomplete occlusion in 14 cases (25.4%). The overall symptomatic periprocedural complication rate was 12.7%. 38 aneurysms underwent follow-up (69%, mean duration 16 months): 33 aneurysms (87%) were completely occluded, 3 aneurysms (8%) had a neck remnant, and 2 aneurysms (5%) were incompletely occluded. CONCLUSION: The Neuroform ATLAS is an effective device for treatment of bifurcation aneurysms, allowing good conformability, a high level of navigability, and easy mesh crossing to perform Y/X stenting procedures. The rate of procedural complications remains non-negligible, and an indication for a double stenting procedure should be carefully discussed in a multidisciplinary meeting.

Efficacy and Safety of a Novel Catheter for Transradial Cerebral Angiography.

BACKGROUND: The goal of this study is to evaluate the safety and efficacy of a novel catheter for right radial artery approach cerebral angiography. METHODS: Patients from the Neurology Department of The Second Affiliated Hospital of Guangxi Traditional Chinese Medical University who underwent diagnostic cerebral angiography of either the left vertebral artery dominant type or balanced type were enrolled in this study. RESULTS: A total of 167 patients were treated between February 2016 and December 2017, of whom 44 were excluded based on study exclusion criteria and 123 were enrolled in the present analysis. Bilateral subclavian artery catheterization and bilateral common carotid artery catheterization were conducted successfully in all 123 patients. The success rate of selective catheterization of the left vertebral artery was 87.8% (108/123). The success rate of selective catheterization of the right vertebral artery using the novel catheter was 89.0% (73/82). The average fluoroscopy time was 6.5 ± 3.4 min, the average operation duration was 47 ± 3.7 (range 50-90) min, and the average dosage of contrast agent was 112.3 ± 8.1 mL. One patient exhibited an absence of pulse in the punctual radial artery after the removal of the arterial compression band, but there was no evidence of ischemia of the distal hand. One patient who was undergoing dual anti-platelet drug treatment suffered from bleeding at the puncture point when deflated for 2 hr after operation; this patient was re-pressurized and re-timed. CONCLUSIONS: This novel catheter improved the success rate of selective left vertebral artery catheterization, and allowed for simplification of the relevant surgical steps. The controllability of this novel catheter was satisfactory, and its associated surgical risk was found to be low.

Intraoperative Fluorescence Cerebral Angiography by Laser Surgical Microscopy: Comparison With Xenon Microscopy and Simultaneous Observation of Cerebral Blood Flow and Surrounding Structures.

BACKGROUND: Laser surgical microscopes should enable uniform illumination of the operative field, and require less luminous energy compared with existing xenon surgical microscopes. OBJECTIVE: To examine the utility of laser illumination in fluorescence cerebral angiography. METHODS: Fluorescein sodium (fluorescein) was used as a fluorescent dye. We first compared the clarity of cerebral blood flow images collected by fluorescence angiography between the laser illumination and xenon illumination methods. We then assessed use of the laser illuminator for simultaneous observation of blood flow and surrounding structures during fluorescence angiography. Furthermore, the study was designed to evaluate usefulness of the thus determined excitation light in clinical cases. RESULTS: Fluorescence angiography using blue light laser for excitation provided higher clarity and contrast blood flow images compared with using blue light generated from a xenon lamp. Further, illumination with excitation light consisting of a combination of 3 types of laser (higher level of blue light, no green light, and lower level of red light) enabled both blood flow and surrounding structures to be observed through the microscope directly by the surgeon. CONCLUSION: Laser-illuminated fluorescence angiography provides high clarity and contrast images of cerebral blood flow. Further, a laser providing strong blue light and weak red light for excitation light enables simultaneous visual observation of fluorescent blood flow and surrounding structures by the surgeon using a surgical microscope. Overall, these data suggest that laser surgical microscopes are useful for both ordinary operative manipulations and fluorescence angiography.

A new method to statistically describe microcatheter tip position in patient-specific aneurysm models.

BACKGROUND AND PURPOSE: Evidence on how to select microcatheters to facilitate aneurysm catheterization during coil embolization is sparse. We developed a new method to define microcatheter tip location inside a patient-specific aneurysm model as a 3-dimensional probability map. We hypothesized that precision and accuracy of microcatheter tip positioning depend on catheter tip shape and aneurysmal geometry. MATERIALS AND METHODS: Under fluoroscopic guidance two to three operators introduced differently shaped microcatheters (straight, 45°, 90°) into eight aneurysm models targeting the anatomic center of the aneurysm. Each microcatheter position was recorded with flat-panel CT, and 3-dimensional probability maps of the microcatheter tip positions were generated. Maps were assessed with histogram analyses and compared between tip shapes, aneurysm locations and operators. RESULTS: Among a total of 530 microcatheter insertions, the precision (mean distance between catheter positions) and accuracy (mean distance to target position) were significantly higher for the 45° tip (1.10±0.64 mm, 3.81±1.41 mm, respectively) than for the 90° tip (1.27±0.57 mm, p=0.010; 4.21±1.60 mm p=0.014, respectively). Accuracy was significantly higher in posterior communicating artery aneurysms (3.38±1.20 mm) than in aneurysms of the internal carotid artery (4.56±1.54 mm, p<0.001). CONCLUSION: Our method can be used tostatistically describe statistically microcatheter behavior in patient-specific anatomy, which may improve the available evidence guiding microcatheter shape selection. Experience increases the ability to reach the intended position with a microcatheter (accuracy) that is also dependent on the aneurysm location, whereas catheter tip choice determines the variability of catheter tip placements versus each other (precision). Clinical validation is required.

The Effect of Vascular Morphology on Selective Left Vertebral Artery Catheterization in Right-sided Radial Artery Cerebral Angiography.

BACKGROUND: The aim of this study is to determine, via retrospective study, the effects of vascular morphology and related factors on the success of selective arterial catheterization of the left vertebral artery when approached via right-sided radial artery cerebral angiography. METHODS: Patients who had undergone diagnostic cerebral angiography were enrolled, and their medical history, catheter type, and vessel morphology were analyzed. RESULTS: A total of 205 patients were enrolled in this study from February 2014 to December 2015. After exclusion according to defined criteria, 161 patients were incorporated into the final analysis. Selective catheterization of the bilateral subclavian artery and the bilateral common carotid artery were conducted successfully in all patients, and the success rate of selective catheterization of the left vertebral artery was 82.0%. The success rate of the left vertebral artery catheterization was positively correlated with the angle between the left vertebral artery and the left subclavicular artery (P < 0.001), with 90° serving as a demarcation point, and this was higher in patients without innominate artery distortion (90.2-75.0%), although this finding was not statistically significant. However, the morphology of the aortic artery did not affect the success rate of selective catheterization of the left vertebral artery (P = 0.189), and there was no significant difference (P = 0.231) in the success rate of selective catheterization if the left vertebral artery was predominant (91.0%, 81/89) or balanced (84.7%, 61/72). A total of 0.9% (2/161) of the patients experienced surgery-related complications. Both these patients exhibited bleeding at the puncture point when they were deflated 2 hr after the operation. They were pressurized and depressurization was again conducted for an appropriate period of time. CONCLUSIONS: The angle between the left vertebral artery and the left subclavicular artery is the primary vessel-associated morphological factor affecting the success rate of selective catheterization of the left vertebral artery in the right-sided radial artery cerebral angiography, while innominate artery distortion also had some more limited impact on this success rate.

Vascular wall imaging in reversible cerebral vasoconstriction syndrome - a 3-T contrast-enhanced MRI study.

BACKGROUND: Limited histopathology studies have suggested that reversible cerebral vasoconstriction syndromes (RCVS) does not present with vascular wall inflammation. Previous vascular imaging studies have had inconsistent vascular wall enhancement findings in RCVS patients. The aim of this study was to determine whether absence of arterial wall pathology on imaging is a universal finding in patients with RCVS. METHODS: We recruited patients with RCVS from Taipei Veterans General Hospital prospectively from 2010 to 2012, with follow-up until 2017 (n = 48). We analyzed the characteristics of vascular wall enhancement in these patients without comparisons to a control group. All participants received vascular wall imaging by contrasted T1 fluid-attenuated inversion recovery with a 3-T magnetic resonance machine. The vascular wall enhancement was rated as marked, mild or absent. RESULTS: Of 48 patients with RCVS, 22 (45.8%) had vascular wall enhancement (5 marked and 17 mild). Demographics, clinical profiles, and cerebral artery flow velocities were similar across patients with versus without vascular wall enhancement, except that patients with vascular wall enhancement had fewer headache attacks than those without (p = 0.04). Follow-up imaging completed in 14 patients (median interval, 7 months) showed reduced enhancement in 9 patients, but persistent enhancement in 5. CONCLUSION: Almost half of our RCVS patients exhibited imaging enhancement of diseased vessels, and it was persistent for approximately a third of those patients with follow-up imaging. Both acute and persistent vascular wall enhancement may be unhelpful for differentiating RCVS from central nervous system vasculitis or subclinical atherosclerosis.

Migraine and Non-Migraine Headaches Following Diagnostic Catheter-Based Cerebral Angiography.

BACKGROUND AND OBJECTIVE: No reliable estimates of headaches following catheter-based cerebral angiography are available. We performed an observational cohort study to ascertain the frequency and type of headaches following catheter-based cerebral angiography. MATERIALS AND METHODS: Consecutive patients who underwent cerebral angiography through the transfemoral (or infrequently radial) route were included. Each patient underwent a brief neurological assessment after the procedure and more detailed assessment was performed if any patient reported occurrence of a headache. The headaches were classified as migraine if the diagnostic criteria specified by International Headache Society were met. The headache severity was classified using a visual numeric rating scale and time to reach pain free status for 2 consecutive hours was ascertained. RESULTS: Migraine headaches occurred in 5 (3.1%, 95% confidence interval [CI] 1.0-7.2%) of 158 patients who underwent cerebral angiography. The median severity of migraine headaches was 10/10 and time to resolution of headaches was 120 minutes (range 60-360 minutes). Migraine headaches occurred in 4 (18.1%, 95% CI 5.2-40.3%) of 22 patients with a history of migraine and 4 (23.5%, 95% CI 6.8-50%) of 17 patients with regular migraine headaches (≥1 episodes per month). Headaches occurred in 6 (3.8%, 95% CI 1.8-8.0%) patients who did not meet the criteria for migraine headaches. CONCLUSIONS: We provide occurrence rates of migraine headaches, an under-recognized adverse event, in patients undergoing catheter-based cerebral angiography.

A Novel Intraoperative Laser Light Imaging System to Simultaneously Visualize Visible Light and Near-Infrared Fluorescence for Indocyanine Green Videoangiography.

BACKGROUND: Intraoperative indocyanine green videoangiography (ICG-VA) has been reported to be utilized in various cerebrovascular surgeries, wherein the blood flow is noticeably shown in white with a black background. ICG flow alone, but not other structures, can be observed using ICG-VA. We developed a novel high-resolution intraoperative imaging system using laser light source for simultaneously visualizing both visible light and near-infrared (NIR) fluorescence images of ICG-VA. METHODS: We used a novel system for 14 cerebrovascular cases. The operative field was illuminated via an operating microscope using a novel laser light source with four bands at 464 (blue), 532 (green), 640 (red), and 785 nm (NIR region). The observed light from the operative field was split using a beam splitter cube into visible (420- 660 nm) and NIR fluorescence emission light (832-900 nm). Images from the color video and NIR fluorescence emission windows were merged for visualization on a monitor screen simultaneously. Laser light was compared with xenon light, and both setups were tested for cerebrovascular surgeries. RESULTS: Laser light has numerous advantages over xenon light. The present setup clearly visualized the color operative field with enhanced blood flow. Complete clipping or incomplete clipping with neck remnant or remnant flow into an aneurysm was confirmed in aneurysm surgeries. Feeding arteries and draining veins were easily distinguished in case of arteriovenous malformation. CONCLUSIONS: Using the present setup, we can observe the color operative field and enhanced blood flow using ICG in real time. This setup could facilitate various cerebrovascular surgeries.