A Multicenter Assessment of Anatomic Suitability for Iliac Branched Devices in Eastern Asian Patients With Unilateral and Bilateral Aortoiliac Aneurysms

Objective: This study aims to assess the suitability of four types of commercial iliac branch device systems to treat Eastern Asian abdominal aortic aneurysm (AAA) patients with bilateral or unilateral common iliac artery aneurysms (CIAAs).Methods: Patients with a coexisting AAA and a unilateral or bilateral CIAAs who underwent endovascular aneurysm repair (EVAR) at two tertiary centers in China from 2015 to 2017 were reviewed. Morphology of lesions was measured and the anatomic suitability for Cook iliac branch device (IBD), Gore iliac branch endoprosthesis (IBE), Lifetech iliac branch stent graft (IBSG), and Jotec IBD was evaluated according to the latest instructions for use.Results: Seventy-six patients with AAA were enrolled, including 35 bilateral CIAAs, 41 unilateral CIAAs. A hundred and eleven lesions were investigated aggregately: 16.2, 28.8, 21.6, and 19.8% met the criteria for Cook IBD, Gore IBE, Lifetech IBSG, and Jotec IBD, respectively. A total of 34 (44.7%) patients could be treated for at least one lateral lesion. The diameter of the internal iliac artery (IIA) was the most common restriction for IBD application. Additionally, the IIA diameter of lesions in the bilateral group was significantly larger compared with the unilateral group (P < 0.001). Based on the anatomical characteristics alone, it is likely that IBDs will be more suitable for unilateral lesions than bilateral ones (P < 0.05). However, there was no difference between the suitability for patients with unilateral or bilateral CIAAs (P > 0.05).Conclusions: Less than half of Eastern Asian patients with aortoiliac aneurysms were eligible for IBD application. This was primarily due to the IIA diameter failing to meet the criteria. And thus, the suitability of lesions in bilateral group was significantly lower than that in the unilateral group. Aiming to expand the indications and optimize the design of the iliac branch devices, IIA diameter and the anatomical characteristics of the bilateral lesions should be considered deliberately.

Optimal Wire Myography Normalization for the Rat Dorsal Penile, Internal Pudendal and Internal Iliac Arteries

In functional arterial studies using wire myography, the determination of a vessel’s standardized normalization factor (factor k) is an essential step to ensure optimal contraction and relaxation by the arteries when stimulated with their respective vasoactive agents and to obtain reproducible results. The optimal factor k for several arteries have been determined; however, the optimal initial tension and factor k for the arteries involved in erection remains unknown. Hence, in the present study we set out to determine the optimal factor k for the internal iliac artery, proximal and distal internal pudendal artery (IPA), and dorsal penile artery. After isolating, harvesting, and mounting the arteries from male Sprague-Dawley rats on a multi wire myograph, we tested arterial responsivity to high K+-stimulation when the factor k was set at 0.7, 0.8, 0.85, 0.9, 0.95, 1.0, 1.1, and 1.2 to determine the factor k setting that results in the greatest K+-induced active force production for each vessel type. The data showed the optimal factor k is 0.90-0.95 for the dorsal penile, distal internal pudendal and internal iliac arteries while it is 0.85-0.90 for proximal internal pudendal artery. These optimal values corresponded to initial passive tension settings of 1.10±0.16 - 1.46±0.23, 1.28±0.20 - 1.69±0.34, 1.03±0.27 - 1.33±0.31, and 1.33±0.31 - 1.77±0.43 mN/mm for the dorsal penile, distal IP, proximal IP, and internal iliac arteries, respectively.

The Bilateral Sacral Origin of a Spinal Dural Arteriovenous Fistula: A Case Report

: Spinal dural arteriovenous fistulas (SDAVFs) are characterized by an abnormal connection between a spinal radicular artery and a perimedullary vein, mainly fed by a radicular artery at the nerve root sleeve. Here, we describe the case of a 40-year-old woman, presenting with progressive weakness of the lower extremities and the sphincter. Thoracic magnetic resonance imaging (MRI) showed spinal cord edema and signal voids on the dorsal surface of the cord. Spinal angiography demonstrated a SDAVF with a nidus at the sacral level; the feeder of the arteriovenous fistula was a lateral sacral artery, as a branch of the internal iliac artery. The lateral sacral artery was subselectively catheterized, and SDAVF was embolized with 25% n-butyl cyanoacrylate (NBCA) glue (glue: lipiodol ratio, 1:3). After embolization, no definite residual connection was visualized between the arterial and venous systems.

Development of Automated Angiogram Labeling via AI Active Learning Pipeline

Background and Objective: As technology is integrated further into medicine, more specialties are discovering new uses for it in their clinical practice. However, the tasks that we want technology to complete are often removed from developer’s intended tasks. A field of research is growing that integrates medicine with current AI technology to bridge the gap and utilize already existing technology for medical uses. We desire to use an active learning pipeline (a form of machine learning) to automate the labeling of blood vessels on angiograms and potentially develop the ability to detect occlusions. By using machine learning, it would essentially allow the machine to teach itself with human guidance. Methods: A machine learning pipeline is in development for automation of the process. To create a baseline for the machine to start learning, the first set of angiograms are being labeled by hand using the program 3D Slicer. For the first pass, we have been quickly labeling the blood vessels by changing the color sensitivity threshold to highlight the darker blood vessels juxtaposed next to lighter tissue. For the second pass, we have erased any erroneous highlighting that was picked up in the first pass such as tools, tissue, contrast outside the injection site, and sutures. For the third pass, we have labeled and segmented the arteries into specific vessels such as femoral, common iliac, internal iliac, etc. This will then be entered into the machine for automated learning. Results: We are in the process of labeling the initial image set. Potential Impact: By creating a lab for angiogram automation, it will allow physicians to efficiently search images for specific arteries and save valuable time usually spent searching images. This would also allow for automated labeling of occlusions that a physician could then look at to verify.

Efficacy of median sacral artery embolization for treating severe pelvic fractures: a retrospective study

Objective Transcatheter arterial embolization (TAE) of bilateral internal iliac arteries (IIAs) in patients with a hemodynamically unstable pelvic fracture is associated with a low mortality rate. The persistence of unstable hemodynamics after IIA embolization indicates the involvement of other arteries, such as the median sacral artery (MSA). This study aimed to evaluate the efficacy of MSA embolization. Methods In this single-center, retrospective, observational study, medical records of patients who underwent MSA angiography or embolization for pelvic fractures (n = 21) between January 2007 and August 2019 were reviewed. The percentage of patients achieving hemodynamic stabilization by MSA embolization was calculated. Results Fifteen patients underwent MSA embolization, and the remaining six underwent MSA angiography. The shock index value was significantly higher after MSA embolization than that before MSA embolization in hemodynamically unstable patients who underwent this procedure. The success rate of MSA selection was 100%. One patient presented with urinary retention because of bladder and rectal disorders after MSA embolization. The 30-day survival rate was 85.7%. Conclusions Severe pelvic fractures, such as a Dennis Zone III fracture and suicidal jumper’s fracture due to trauma from a fall, may require MSA embolization.

Sacral insufficiency fractures are a risk of massive bleeding during sacrectomy: patient series

BACKGROUND Sacrectomy carries significant risk of bleeding; however, specific risk factors, apart from medical comorbidities and tumor type, for this life-threatening complication remain unclear. This study describes two cases of massive bleeding, including one death during sacrectomy attributable to adherence of the internal iliac vein (IIV) and its neuroforaminal tributaries from sacral insufficiency fractures. OBSERVATIONS The authors presented two cases involving patients who received sacrectomy for a chordoma and experienced massive bleeding from the IIV due to adherence of the IIV and its neuroforaminal tributaries around sacral insufficiency fractures. They assessed their institution’s previous two decades’ experience of sacrectomies to determine risk factors for massive bleeding and performed anatomical dissection of 20 hemipelvises, which revealed the close proximity of the IIV to the sacral foraminae and the consistency of neuroforaminal tributaries arising from the foraminae. LESSONS Sacral insufficiency fractures may cause scarring that adheres to the IIV and its neuroforaminal tributaries, which risks massive bleeding during sacrectomy.