Experimental study using phantom models of cerebral aneurysms and 4D-DSA to measure blood flow on 3D-color-coded images.

BACKGROUND: The current 3D-iFlow application can only measure the arrival time of contrast media through intensity values. If the flow rate could be estimated by 3D-iFlow, patient-specific hemodynamics could be determined within the scope of normal diagnostic management, eliminating the need for additional resources for blood flow rate estimation. OBJECTIVE: The aim of this study is to develop and validate a method for measuring the flow rate by data obtained from 3D-iFlow images - a prototype application in Four-dimensional digital subtraction angiography (4D-DSA). METHODS: Using phantom model and experimental circuit with circulating glycerin solution, an equation for the relationship between contrast media intensity and flow rate was developed. Applying the equation to the aneurysm phantom models, the derived flow rate was evaluated. RESULTS: The average errors between the derived flow rate and setting flow rate became larger when the glycerin flow and the X-rays from the X-ray tube of the angiography system were parallel to each other or when the measurement point included overlaps with other contrast enhanced areas. CONCLUSION: Although the error increases dependent on the imaging direction and overlap of contrast enhanced area, the developed equation can estimate the flow rate using the image intensity value measured on 3D-iFlow based on 4D-DSA.

Diagnostic Value of High-Resolution Vessel Wall Imaging Technique in Intracranial Arterial Stenosis and Occlusion: A Comparative Analysis with Digital Subtraction Angiography.

Objective: To analyze the diagnostic value of HR-VWI in intracranial arterial stenosis and occlusion and compare it with DSA. Methods: A retrospective analysis of clinical data of 59 patients with intracranial arterial stenosis in our hospital was conducted to compare the diagnostic results of the two methods for different degrees of intracranial stenosis and various morphological plaques. Results: The diagnosis of stenosis and occlusion by both methods showed no significant difference (P > 0.05). Comparison of plaque morphology detected by HR-VWI with pathological examination results showed no significant difference (P > 0.05); however, there was a significant difference between plaque morphology detected by DSA and pathological examination results (P < 0.05). Additionally, there was a significant difference between plaque morphology detected by HR-VWI and DSA (P < 0.05). Conclusion: HR-VWI technique is comparable to DSA technique in diagnosing intracranial arterial stenosis and occlusion, but it is superior to DSA in plaque morphology diagnosis.

Mediastinal hematoma after trans-radial cerebral angiography: a case report.

BACKGROUND: Trans-radial (TRA) access has become increasingly prevalent in neurointervention. Nonetheless, mediastinal hematoma after TRA is an infrequent yet grave complication associated with a notably elevated mortality rate. While our review found no reported mediastinal hematoma cases managed conservatively within neuro-interventional literature, similar complications are documented in cardiac and vascular interventional radiology, indicating its potential occurrence across disciplines. CASE PRESENTATION: Carotid computed tomography angiography (CTA) showed calcified plaques with stenosis (Left: Severe, Right: Moderate) in the bilateral internal carotid arteries (ICAs) of an 81-year-old male presented with paroxysmal weakness in the right upper limb. Dual antiplatelet therapy with aspirin and clopidogrel was administered. On day 7, DSA of the bilateral ICAs was performed via TRA. Post-DSA, the patient experienced transient loss of consciousness, chest tightness, and other symptoms without ECG or MRI abnormalities. Hemoglobin level decreased from 110 g/L to 92 g/L. Iodinated contrast-induced laryngeal edema was suspected, and the patient was treated with intravenous methylprednisolone. Neck CT indicated a possible mediastinal hemorrhage, which chest CTA confirmed. The patient's treatment plan involved discontinuing antiplatelet medication as a precautionary measure against the potential occurrence of an ischemic stroke instead of the utilization of a covered stent graft and surgical intervention. Serial CTs revealed hematoma absorption. Discharge CT showed a reduced hematoma volume of 35 × 45 mm. CONCLUSIONS: This case underscores the need for timely identification and precise manipulation of guidewires and guide-catheters through trans-radial access. The critical components of successful neuro-interventional techniques include timely examination, rapid identification, proper therapy, and diligent monitoring.

Comparison of feasibility and effectiveness of tunneled dialysis catheter placement with or without DSA guidance: a propensity score-matched cohort study.

BACKGROUND: In some resource-limited regions, the placement of tunneled dialysis catheters (TDC) is often preferred under ultrasound guidance rather than fluoroscopy. This study compared ultrasound-and digital subtraction angiography-guided (DSA)-guided TDC in renal replacement therapy. METHODS: This retrospective cohort study included all TDC placements performed at our hospital between January 2020 and October 2022. We utilized 1:1 propensity score matching (PSM) to balance the demographic and clinical characteristics of the DSA-guided and ultrasound-guided groups. Dialysis prescriptions and actual dialysis completion were assessed using intraclass correlation coefficients (ICC). Multivariable logistic regression analyses determined the risk factors for early termination of dialysis. The differences in adverse events, catheter function, and catheter tip position were evaluated between the two groups. RESULTS: The study included 261 patients (142 in the DSA-guided group and 119 in the ultrasound-guided group). After PSM, 91 patients were included in each group, with no significant baseline differences (p > .1). Both groups achieved adequate catheter blood flow and ultrafiltration volumes without deviations from dialysis prescriptions (ICC ≥ 0.75). The DSA-guided group had fewer early dialysis terminations than the ultrasound-guided group (3.3 vs. 12.0%, p = .026). The position of the catheter tip in the right atrium was more consistent in the DSA-guided group (100 vs. 74.2%, p < .001). CONCLUSION: Hemodialysis catheters inserted under DSA guidance exhibited superior performance compared to those inserted under ultrasound guidance, primarily due to more accurate catheter tip positioning. DSA guidance is recommended when ensuring optimal catheter tip placement.

DIAS: A dataset and benchmark for intracranial artery segmentation in DSA sequences.

The automated segmentation of Intracranial Arteries (IA) in Digital Subtraction Angiography (DSA) plays a crucial role in the quantification of vascular morphology, significantly contributing to computer-assisted stroke research and clinical practice. Current research primarily focuses on the segmentation of single-frame DSA using proprietary datasets. However, these methods face challenges due to the inherent limitation of single-frame DSA, which only partially displays vascular contrast, thereby hindering accurate vascular structure representation. In this work, we introduce DIAS, a dataset specifically developed for IA segmentation in DSA sequences. We establish a comprehensive benchmark for evaluating DIAS, covering full, weak, and semi-supervised segmentation methods. Specifically, we propose the vessel sequence segmentation network, in which the sequence feature extraction module effectively captures spatiotemporal representations of intravascular contrast, achieving intracranial artery segmentation in 2D+Time DSA sequences. For weakly-supervised IA segmentation, we propose a novel scribble learning-based image segmentation framework, which, under the guidance of scribble labels, employs cross pseudo-supervision and consistency regularization to improve the performance of the segmentation network. Furthermore, we introduce the random patch-based self-training framework, aimed at alleviating the performance constraints encountered in IA segmentation due to the limited availability of annotated DSA data. Our extensive experiments on the DIAS dataset demonstrate the effectiveness of these methods as potential baselines for future research and clinical applications. The dataset and code are publicly available at https://doi.org/10.5281/zenodo.11401368 and https://github.com/lseventeen/DIAS.

Clinical Presentation of Carotid-Cavernous Fistula and Outcomes of Endovascular Balloon Embolization

Objectives: To describe the clinical presentation of carotico-cavernous fistula (CCF) and outcomes of endovascular balloon embolization in a tertiary care center in a developing country. Materials and Methods: This retrospective interventional case series included 18 patients who underwent endovascular balloon embolization from 2019 to 2022 at Lahore General Hospital in Lahore, Pakistan. The analyzed data consisted of age, gender, cause and type of CCF, clinical presentation, diagnostic technique used, intervention, and the results of two-month follow-up. Patients with incomplete records and coil embolization were excluded. Digital subtraction angiography was done in all cases followed by endo-arterial balloon embolization. Procedures were carried out under general anesthesia via femoral artery approach. A single balloon was sufficient to close the fistula in all cases. Results: There were 18 patients who met the inclusion criteria. Sixteen patients had direct CCF, and the mean age of the patients was 27.2±12.6 years. The commonest cause of CCF was trauma, and the mean time of presentation after trauma was 7.89±7.19 months. The male-to-female ratio was 8:1. Preoperative visual acuity was worse than 6/60 in 8 patients, between 6/60 and 6/18 in 7 patients, and better than 6/18 in 3 patients. The mean intraocular pressure was 16.06±3.37 mmHg preoperatively and 14.83±3.49 mmHg postoperatively (p=0.005). Endovascular embolization was successful in 15 patients (83.3%). One patient developed epidural hematoma as a complication of the procedure, which was drained later. There was no mortality related with the procedure. Conclusion: Balloon embolization via the femoral artery is an efficient technique in direct as well as indirect CCF. It is safe and simple with very good results if performed in a timely manner.

Evaluation of paclitaxel-coated balloon angioplasty for the treatment of symptomatic intracranial in-stent restenosis.

Background: Symptomatic intracranial in-stent restenosis (sISR) poses a major challenge in the management of cerebrovascular diseases, often requiring effective and safe treatment options. Objectives: This study aims to evaluate the efficacy and safety of paclitaxel-coated balloon (PCB) angioplasty for treating sISR. Methods: We conducted a retrospective analysis of five patients aged 49-74 years, who were treated with PCB angioplasty between January 2017 and June 2022. Treatment procedures included pre-operative digital subtraction angiography, antiplatelet therapy, and the use of the SeQuent Please balloon. Patients received aspirin and clopidogrel prior to and after the procedure. Results: The procedure achieved a 100% success rate. The degree of ISR was significantly reduced from an average pre-operative rate of 72±18.9% to a post-operative rate of 34±8.22%. Long-term follow-up showed that the majority of patients did not experience restenosis, confirming the long-term effectiveness of the treatment. Conclusions: PCB angioplasty demonstrates significant potential as an effective and safe treatment option for patients with sISR, especially those considered to be at high risk. This study supports further investigation into PCB angioplasty as a standard treatment for sISR.

VESCL: an open source 2D vessel contouring library.

PURPOSE: VESCL (pronounced 'vessel') is a novel vessel contouring library for computer-assisted 2D vessel contouring and segmentation. VESCL facilitates manual vessel segmentation in 2D medical images to generate gold-standard datasets for training, testing, and validating automatic vessel segmentation. METHODS: VESCL is an open-source C++ library designed for easy integration into medical image processing systems. VESCL provides an intuitive interface for drawing variable-width parametric curves along vessels in 2D images. It includes highly optimized localized filtering to automatically fit drawn curves to the nearest vessel centerline and automatically determine the varying vessel width along each curve. To support a variety of segmentation paradigms, VESCL can export multiple segmentation representations including binary segmentations, occupancy maps, and distance fields. RESULTS: VESCL provides sub-pixel resolution for vessel centerlines and vessel widths. It is optimized to segment small vessels with single- or sub-pixel widths that are visible to the human eye but hard to segment automatically via conventional filters. When tested on neurovascular digital subtraction angiography (DSA), VESCL's intuitive hand-drawn input with automatic curve fitting increased the speed of fully manual segmentation by 22× over conventional methods and by 3× over the best publicly available computer-assisted manual segmentation method. Accuracy was shown to be within the range of inter-operator variability of gold standard manually segmented data from a publicly available dataset of neurovascular DSA images as measured using Dice scores. Preliminary tests showed similar improvements for segmenting DSA of coronary arteries and RGB images of retinal arteries. CONCLUSION: VESCL is an open-source C++ library for contouring vessels in 2D images which can be used to reduce the tedious, labor-intensive process of manually generating gold-standard segmentations for training, testing, and comparing automatic segmentation methods.

Color Duplex Ultrasonography for the Evaluation of Innominate, Subclavian, and Common Carotid Artery Stenosis.

OBJECTIVE: This study aimed to validate the efficiency of Doppler ultrasonography for predicting the innominate, subclavian, and common carotid artery stenosis. METHODS: This retrospective multicenter study between 2013 and 2022 enrolled 636 patients who underwent carotid Doppler ultrasonography and subsequent digital subtraction angiography. And 58 innominate artery stenosis, 147 common carotid artery stenosis, and 154 subclavian artery stenosis were included. The peak systolic velocity at innominate, subclavian, and common carotid artery, and velocity ratios of innominate artery to common carotid artery, innominate artery to subclavian artery, and common carotid artery to internal carotid artery were measured or calculated. The threshold values were determined using receiver operating characteristic analysis. RESULTS: The threshold values of innominate artery stenosis were peak systolic velocity >206 cm/s (sensitivity: 82.8%; specificity: 91.4%) to predict ≥50% stenosis and >285 cm/s (sensitivity: 89.2%; specificity: 94.9%) to predict ≥70% stenosis. The threshold values of common carotid artery stenosis were peak systolic velocity >175 cm/s (sensitivity: 78.2%; specificity: 91.9%) to predict ≥50% stenosis and >255 cm/s (sensitivity: 87.1%; specificity: 87.2%) to predict ≥70% stenosis. The threshold values of subclavian artery stenosis were peak systolic velocity >200 cm/s (sensitivity: 68.2%; specificity: 84.4%) to predict ≥50% stenosis and >305 cm/s (sensitivity: 57.9%; specificity: 91.4%) to predict ≥70% stenosis. CONCLUSIONS: Symptomatic patients with ultrasonic parameters of velocity at innominate artery ≥206 cm/s, velocity at common carotid artery ≥175 cm/s, or velocity at subclavian artery ≥200 cm/s need to be considered for further verification and whether revascularization is necessary.

Semi-automatic computed tomography angiography quantification assessment is an alternative method to digital subtraction angiography in intracranial stenosis: a multicenter study.

Background: The recent randomized controlled trials studying intracranial atherosclerotic stenosis (ICAS) have used digital subtraction angiography (DSA) to quantify stenosis and enroll patients. However, some disadvantages of DSA such as invasive features, contrast agent overuse, and X-ray radiation overexposure, were not considered in these studies. This study aimed to explore whether computed tomography angiography (CTA) with semi-automatic analysis could be an alternative method to DSA in quantifying the absolute stenotic degree in clinical trials. Methods: Patients with 50-99% ICAS were consecutively screened, prospectively enrolled, and underwent CTA and DSA between March 2021 and December 2021 at 6 centers. This study was registered at www.chictr.org.cn (ChiCTR2100052925). The absolute stenotic degree of ICAS on CTA with semi-automatic analysis was calculated by several protocols using minimal/maximum/mean diameters of stenosis and reference site from a semi-automatic analysis software. Intraclass correlation coefficient (ICC) was used to evaluate the reliabilities of quantifying stenotic degree on CTA. The optimal protocol for quantifying ICAS on CTA was explored. The agreements of quantifying ICAS in calcified or non-calcified lesions and 50-69% or 70-99% stenosis on CTA and DSA were assessed. Results: A total of 191 participants (58.8±10.7 years; 148 men) with 202 lesions were enrolled. The optimal protocol for quantifying ICAS on CTA was calculated as (1 - the minimal diameter of stenosis/the mean diameter of reference) × 100% for its highest agreement with DSA [ICC, 0.955, 95% confidence interval (CI): 0.944-0.966, P<0.001]. Among the 202 lesions, 80.2% (162/202) exhibited severe stenosis on DSA. The accuracy of CTA in detecting severe ICAS was excellent (sensitivity =95.1%, positive predictive value =98.1%). The agreements between DSA and CTA in non-calcified lesions (ICC, 0.960 vs. 0.849) and severe stenosis (ICC, 0.918 vs. 0.841) were higher than those in calcified lesions and moderate stenosis. Conclusions: CTA with semi-automatic analysis demonstrated an excellent agreement with DSA in quantifying ICAS, making it promising to replace DSA for the measurement of absolute stenotic degree in clinical trials.

Comparative analysis of the efficacy and safety of different methods for injecting polidocanol in the treatment of venous malformations.

OBJECTIVE: To compare and analyze the efficacy and safety of different methods for injecting polidocanol in the treatment of venous malformations. METHODS: The medical records of patients with venous malformations in our hospital from April 2021 to April 2023 were analyzed retrospectively, and they were divided into control group (n = 38) and observation group (n = 20) according to different treatment methods. Control group was injected with polidocanol under ultrasound guidance, while observation group was injected with polidocanol under digital subtraction angiography (DSA) monitoring. Therapeutic effects of observation group and control group after 3-6 months of treatment were compared and analyzed, and complications that can be used to reflect the safety of treatment in two groups were collected and recorded. RESULTS: After treatment, the total effective rates of observation group and control group were 97.37% (37/38) and 75.00% (15/20) respectively, with significant differences (both p < .05). After 3-6 months of treatment, 13 complications occurred in observation group, while 16 occurred in control group. The number of complications in observation group was 6, with an incidence rate of 15.78%; while that in control group was 9, with an incidence rate of 45.00%, with a significant difference (p < .05). There were no significant differences among other baseline data, age and complications between two groups (all p > .05). CONCLUSION: Injection of polidocanol in patients with venous malformations under DSA monitoring was more effective and safer.

Digital Subtraction Angiography of Cerebral Arteries: Influence of Cranial Dimensions on X-ray Tube Performance.

(1) Background. Digital subtraction angiography (DSA) is indispensable for diagnosing cerebral aneurysms due to its superior imaging precision. However, optimizing X-ray parameters is crucial for accurate diagnosis, with X-ray tube settings significantly influencing image quality. Understanding the relationship between skull dimensions and X-ray parameters is pivotal for tailoring imaging protocols to individual patients. (2) Methods. A retrospective analysis of DSA data from a single center was conducted, involving 251 patients. Cephalometric measurements and statistical analyses were performed to assess correlations between skull dimensions and X-ray tube parameters (voltage and current). (3) Results. The study revealed significant correlations between skull dimensions and X-ray tube parameters, highlighting the importance of considering individual anatomical variations. Gender-based differences in X-ray parameters were observed, emphasizing the need for personalized imaging protocols. (4) Conclusions. Personalized approaches to DSA imaging, integrating individual anatomical variations and gender-specific differences, are essential for optimizing diagnostic outcomes. While this study provides valuable insights, further research across multiple centers and diverse imaging equipment is warranted to validate these findings.

The diagnostic yield of repeat computed tomography angiography in cases of spontaneous subarachnoid haemorrhage after negative initial digital subtraction angiography.

Purpose: It is currently unclear how useful repeat computed tomography angiography (CTA) is in spontaneous subarachnoid haemorrhage (SAH) patients after negative initial digital subtraction angiography (DSA). The purpose of this study is to assess the yield of repeat CTA for the detection of causative vascular lesions in patients with SAH in whom there has been a negative initial DSA. Material and methods: This observational retrospective study was carried out from January 2013 to July 2022 at a single institution. Analysis of the SAH pattern on unenhanced CT showed that patients were divided into perimesencephalic SAH and diffuse SAH groups. A repeat CTA was performed on all spontaneous SAH patients who had a nega-tive initial CTA and DSA within a 2-week period. An interventional neuroradiologist and a diagnostic radiologist examined all images to search for causative vascular abnormalities. Results: Forty-seven patients were included in our study, with a median age of 55 years and a range of 28-81 years. Thirty-seven had diffuse SAH (66%), and 16 had perimesencephalic SAH (34%). The repeat CTA revealed 2 causa-tive vascular lesions (a right PICA aneurysm and a mycotic aneurysm) in 2 separate patients (yield of 4.3%), both of whom had diffuse SAH (yield of 6.5%). In retrospect, none of these vascular lesions were evident in the initial CTA and DSA. No evidence of re-bleeding was observed in the follow-up period. Conclusions: It is beneficial to repeat CTA when evaluating patients with diffuse SAH who initially present with nega-tive initial DSA. For occult aneurysms, the diagnostic yield of the follow-up CTA is 6.5%.

Diagnostic performance of computed tomography-digital subtraction angiography and conventional magnetic resonance imaging for evaluating the vascularity of osseous spinal tumors.

BACKGROUND AND PURPOSE: Patients with hypervascular spinal tumors may have severe blood loss during tumor resection, which increases the risks of perioperative morbidity and mortality. However, the preoperative evaluation of tumor vascularity may be challenging; moreover, the reliability of the data obtained in conventional preoperative noninvasive imaging is debatable. In this study, we compared conventional magnetic resonance imaging (MRI) and subtraction computed tomography angiography (CTA) in terms of their performance in vascularity evaluation. The catheter digital subtraction angiography (DSA) technique was used as a reference standard. METHODS: This study included 123 consecutive patients with spinal tumor who underwent subtraction CTA, catheter DSA, and subsequent surgery between October 2015 and October 2021. Data regarding qualitative and semiquantitative subtraction CTA parameters and conventional MRI signs were collected for comparison with tumor vascularity graded through catheter DSA. The diagnostic performance of qualitative CTA, quantitative CTA, and conventional MRI in assessing spinal tumor vascularity was analyzed. RESULTS: Qualitative subtraction CTA was the best noninvasive imaging modality in terms of diagnostic performance (area under the receiver operating characteristic curve [AUROC], 0.95). Quantitative CTA was relatively inferior (AUROC, 0.87). MRI results had low reliability (AUROC, 0.51 to 0.59). Intratumoral hemorrhage and prominent foraminal venous plexus were found to be the specific signs for hypervascularity (specificity 93.2%). CONCLUSIONS: Qualitative subtraction CTA offers the highest diagnostic value in evaluating spinal tumor vascularity, compared to quantitative CTA and MRI. Although conventional MRI may not be a reliable approach, certain MRI signs may have high specificity, which may be crucial for assessing spinal tumor vascularity.

Comparative diagnostic efficacy of cranial CT, CTA, and DSA in subarachnoid hemorrhage management: A systematic review and meta-analysis.

INTRODUCTION: Subarachnoid hemorrhage (SAH) is a critical medical condition associated with high morbidity and mortality rates. Timely and accurate diagnosis is crucial for optimal patient outcomes. Cranial computed tomography (CT), computed tomography angiography (CTA), and digital subtraction angiography (DSA) are commonly used imaging modalities for diagnosing SAH, but their comparative diagnostic efficacy remains debated. METHODS: A systematic review and meta-analysis was conducted to evaluate the diagnostic performance of cranial CT, CTA, and DSA in identifying SAH. PubMed, Google scholar, Cochrane Library databases were searched for relevant studies published up to January 2024. Pooled sensitivity, specificity, and the summary receiver operating characteristic (SROC) curve were calculated using Review Manager 5.4. RESULTS: A total of 31 studies involving 10,287 patients were included in the analysis. The pooled sensitivity of cranial CT for detecting SAH was 94.7 % (95 % Confidence Interval, CI) with a specificity of 98.3 % (95 % CI). CTA demonstrated a pooled sensitivity of 94.1 % (95 % CI) and specificity of 93.4 % (95 % CI). DSA showed a pooled sensitivity of 87.7 % (95 % CI) and specificity of 95.8 % (95 % CI). The SROC curve demonstrated discriminatory ability for all modalities. CONCLUSION: Cranial CT, CTA, and DSA are valuable imaging modalities for diagnosing SAH, with high sensitivity and specificity. Cranial CT serves as an initial screening tool, while CTA offers superior sensitivity in detecting aneurysmal SAH. DSA remains essential in specific clinical scenarios. Further prospective studies are needed to validate these findings and refine diagnostic guidelines for SAH.

Comparison of Vertebral Artery Ultrasound, Magnetic Resonance Angiography and Digital Subtraction Angiography in the Diagnosis of Vertebral Artery Stenosis in Patients with Posterior Circulation Ischemia

SUMMARY: The aim of this study was to compare the clinical value of vertebral artery ultrasound (VAU), Magnetic Resonance Angiography (MRA) and Digital Subtraction Angiography (DSA) on vertebral artery stenosis in patients with posterior circulation ischemia. Seventy-three patients with posterior circulation ischemia underwent vertebral artery ultrasound and magnetic resonance angiography as well as digital subtraction angiography, and the diagnosis of vertebral artery stenosis (VAS) and the degree of stenosis (normal, mild stenosis, moderate stenosis, severe stenosis, and occlusion) were recorded and compared between digital subtraction angiogram and vertebral artery ultrasound and magnetic resonance angiography. The vertebral artery stenosis rates on digital subtraction angiography and vertebral artery ultrasound were 87.30 % (55/63) and 49.20 % (31/63), respectively, and the difference was statistically significant. The rates of vertebral artery stenosis on digital subtraction angiography and, magnetic resonance angiography was 90.38 % (47/52) and 88.46 % (46/ 52), respectively, and the differences was not statistically significant. The sensitivity, accuracy, negative predictive value, and positive predictive value of vertebral artery ultrasound in diagnosing vertebral artery stenosis were 51.35 %, 54.76 %, 18.18 %, and 95.00 %, respectively, lower than those of magnetic resonance angiography, which were 91.89 %, 90.48 %, 57.14 %, and 97.14 %, respectively. Of the noninvasive imaging techniques, vertebral artery ultrasound does not accurately characterize vertebral artery stenosis and its degree of stenosis. Magnetic resonance angiography effectively screens for vertebral artery stenosis and its degree of stenosis, and can be used as a reliable tool for vertebral artery stenosis in posterior circulation cerebral infarction, and can be used in conjunction with digital subtraction angiogram in order to improve diagnostic convenience and accuracy.

El objetivo de este estudio fue comparar el valor clínico de la ecografía de la arteria vertebral (VAU), la angiografía por resonancia magnética (ARM) y la angiografía por sustracción digital (DSA) en la estenosis de la arteria vertebral en pacientes con isquemia de la circulación posterior. A 73 pacientes con isquemia de la circulación posterior se les realizó una ecografía de la arteria vertebral y una angiografía por resonancia magnética, así como una angiografía por sustracción digital, y se les diagnosticó estenosis de la arteria vertebral (EVA) y el grado de estenosis (normal, estenosis leve, estenosis moderada, estenosis grave, y oclusión) se registraron y compararon la angiografía por sustracción digital y la ecografía de la arteria vertebral y la angiografía por resonancia magnética. Las tasas de estenosis de la arteria vertebral en la angiografía por sustracción digital y la ecografía de la arteria vertebral fueron del 87,30 % (55/63) y del 49,20 % (31/63), respectivamente, y la diferencia fue estadísticamente significativa. Las tasas de estenosis de la arteria vertebral en la angiografía por sustracción digital y la angiografía por resonancia magnética fueron del 90,38 % (47/52) y del 88,46 % (46/52), respectivamente, y las diferencias no fueron estadísticamente significativas. La sensibilidad, precisión, valor predictivo negativo y valor predictivo positivo de la ecografía de la arteria vertebral en el diagnóstico de estenosis de la arteria vertebral fueron 51,35 %, 54,76 %, 18,18 % y 95,00 %, respectivamente, inferiores a los de la angiografía por resonancia magnética, que fueron 91,89 %, 90,48 %, 57,14 % y 97,14 %, respectivamente. De las técnicas de imagen no invasivas, la ecografía de la arteria vertebral no caracteriza con precisión la estenosis de la arteria vertebral y su grado de estenosis. La angiografía por resonancia magnética detecta eficazmente la estenosis de la arteria vertebral y su grado de estenosis, y puede usarse como una herramienta confiable para la estenosis de la arteria vertebral en el infarto cerebral de circulación posterior, y puede ser utilizada junto con la angiografía por sustracción digital para mejorar el diagnóstico y la exactitud.

Bilateral Inferior Petrosal Sinus Sampling Without Lateralization Is Less Accurate for the Diagnosis of Cushing Disease.

Context: During bilateral inferior petrosal sinus sampling (BIPSS), the side-to-side adrenocorticotropic hormone (ACTH) ratio, referred to as sampling lateralization, was used to predict pituitary adenoma localization. Objective: To investigate the potential different diagnostic accuracy of BIPSS for differentiating Cushing disease (CD) and ectopic ACTH secretory syndrome (EAS) patients with low lateralization (inferior petrosal sinus [IPS]:IPS ≤ 1.4) and high lateralization (IPS:IPS > 1.4). Methods: This single-center retrospective study (2011-2021) included (all patients had BIPSS results and confirmed pathologic diagnoses) 220 consecutive CD patients (validation set), 30 EAS patients, and 40 of the CD patients who had digital subtraction angiography (DSA) videos (discovery set). Results: In the discovery set, the low-lateralization CD group (n = 11) had a higher median plasma ACTH concentration (62.2, IQR 44.7-181.0 ng/L) than the high-lateralization CD group (n = 29) (33.0, IQR 18.5-59.5, P = .013). Lower IPS to peripheral ratios were observed in the low-lateralization group during BIPSS, both before and after stimulation (P = .013 and P = .028). The sensitivity of BIPSS before stimulation in differentiating CD from EAS was lower in the low-lateralization group than the high-lateralization group (54.6% vs 93.1%, P = .003), as validated in the validation set. DSA videos revealed higher vascular area difference visible in the 2 sides of the pituitary in low lateralization (median 1.2 × 105 pixels, IQR 0.5-1.8) than the high-lateralization group (0.4 × 105 pixels, IQR 0.1-0.7, P = .008). The vascular area ratio of the 2 sides was also significantly higher in low (1.55, IQR 1.31-2.20) than high lateralization (1.19, IQR 1.07-1.35, P = .010). Conclusion: Our study suggested that low lateralization in CD patients may reduce the diagnostic sensitivity of BIPSS, which might be potentially associated with peripituitary vascular anatomy.

Relevance of the Foramen of Vesalius for Preoperative Tumor Embolization in Skull Base Meningioma.

OBJECTIVE: The objective of this study was to investigate the role of the foramen of Vesalius (FV) in the pathogenesis of skull base meningioma by analyzing data from various multi-image modalities. METHODS: For this single-center retrospective study, 39 consecutive patients with skull base meningioma who underwent tumor resection between January 2020 and March 2023 were enrolled. The anatomical and pathological characteristics of the FV were evaluated using computed tomography and 3-dimensional digital subtraction angiography. The clinical significance of the FV in tumor hemodynamics and treatment, such as preoperative tumor embolization, was investigated using the 3-dimensional digital subtraction angiography/computed tomography fusion images. RESULTS: We identified FV in 52% (17/27) of the finally included patients. In 10 (30%) patients, the FV was found bilaterally with no significant variation in appearance between the healthy and tumor-affected sides (P = 0.786). The mean FV diameter was significantly larger on the tumor-affected side (P = 0.010). No significant anatomical differences, like duplication and partial assimilation with the foramen ovale, were observed between the 2 sides. The FV was involved in venous skull base perfusion around the tumor in 9 cases. In 4 cases where it was the pathway for tumor feeders, preoperative tumor embolization via the FV resulted in disappearance of the tumor stain. No complications associated with endovascular treatment were observed. CONCLUSIONS: This study elucidated the anatomical asymmetry of the FV and its role in the hemodynamics of skull base meningioma. Our findings highlight the significance of performing anatomical and pathological evaluations of the FV in determining treatment strategies, including preoperative embolization, for skull base lesions.

Cerebral Vasospasm After Burr Hole Evacuation of Chronic Subdural Hematoma.

Cerebral vasospasm is a frequent complication of subarachnoid hemorrhage. We report a case of chronic subdural hematoma complicated by cerebral vasospasm after burr hole evacuation. A 74-year-old woman underwent burr hole evacuation of a chronic subdural hematoma. She developed left hemiparesis and disturbance of consciousness on postoperative day 3. Magnetic resonance imaging showed a right parietal infarct and decreased cerebral blood flow signal in the right middle cerebral artery territory. Digital subtraction angiography showed multiple segmental narrowings of the right middle cerebral artery. Her neurological symptoms recovered with conservative treatment. Follow-up angiography showed improvement in the arterial narrowing, which finally led to a diagnosis of cerebral vasospasm. Cerebral vasospasm can occur after burr hole evacuation of chronic subdural hematoma. Magnetic resonance angiography is useful for determining the cause of postoperative neurological worsening in chronic subdural hematoma patients.

Renal artery pseudoaneurysm following robot assisted nephron sparing surgery: two case reports.

BACKGROUND: Renal artery pseudoaneurysm following partial nephrectomy is a rare entity, the incidence of this entity is more common following penetrating abdominal injuries, percutaneous renal interventions such as percutaneous nephrostomy(PCN) or Percutaneous nephrolithotomy (PCNL). Although rare, renal artery pseudoaneurysm can be life threatening if not managed timely, they usually present within two weeks postoperatively with usual presenting complains being gross haematuria, flank pain and/or anaemia. CASE PRESENTATION: We report case of two female patients 34 and 57 year old respectively of South Asian ethnicity, presenting with renal artery pseudoaneurysm following left sided robot assisted nephron sparing surgery for interpolar masses presenting clinically with total, painless, gross haematuria with clots within fifteen days postoperatively and their successful treatment by digital subtraction angiography and coil embolization. CONCLUSION: Renal artery aneurysm is a rare fatal complication of minimally invasive nephron sparing surgery however considering the preoperative and intraoperative risk factors for its development and prompt suspicion at the outset can be life saving with coil embolization of the bleeding arterial aneurysm.