Biodegradable Polydioxanone Microspheres for Transcatheter Arterial Embolization: Proof of Principle

PurposeTo evaluate feasibility, embolization success, biodegradability, reperfusion, and biocompatibility of biodegradable microspheres (MS) made from polydioxanone (PDO) for transcatheter arterial embolization.Materials and MethodsUnilateral selective renal embolization of a segmental artery was performed in 16 New Zealand White rabbits with PDO-MS (100–150 μm and 90–315 μm). Animals were randomly assigned to different observation periods and underwent control digital subtraction angiography (DSA) and MR imaging immediately (n = 3), 1 week (n = 2), 4 weeks (n = 2), 8 weeks (n = 2), 12 weeks (n = 5), and 16 weeks (n = 2) after embolization. Kidneys were harvested for macroscopic and histologic analysis of embolization success, biodegradability, and biocompatibility.ResultsEmbolization was technically successful in 15 of 16 animals. One animal died of anesthesia-related circulatory failure. The 100–150 μm MS were injected easily through 3-F catheters; the 90–315 μm MS tended to clog with intermittent catheter obstruction. DSA and MR imaging showed successful target embolization in 13 of 15 animals. In 2 animals, the entire kidney was affected owing to catheter clogging, including a reflux of MS while flushing. Control DSA and MR imaging showed increasing vascular reperfusion with time. Macroscopic and histologic analysis revealed necrosis/infarction in areas in which embolization was achieved. MS were extensively degraded after 16 weeks, and overall inflammatory reaction was mild.ConclusionsBiodegradable PDO-MS induced effective embolization of target vessels while demonstrating good biocompatibility. MS increasingly dissolved at 16 weeks, partial reperfusion started at week 1, and complete reperfusion started at week 8, thus offering possible advantages as a temporary embolic agent.     

Inline Balloon Occlusion–Assisted Delivery of Ethylene Vinyl Alcohol Copolymer for Peripheral Arterial Applications: A Multicenter Case Series

PurposeTo assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications.Materials and MethodsSix academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11–94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1–5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications.ResultsBalloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred.ConclusionsBalloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s).     

Prostatic Artery Embolization—Anatomic Predictors of Technical Outcomes

PurposeTo determine if cone-beam CT and digital subtraction angiography analysis of pelvic arterial anatomy has predictive value for radiation exposure and technical success of prostatic artery embolization (PAE).Materials and MethodsThis prospective, nonrandomized, single-center study included 104 consecutive patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia. Cone-beam CT was performed in 160/208 (76.9%) hemipelves to determine prostatic artery (PA) origin. Classification of pelvic arterial tortuosity was possible in 73/104 (70.2%) patients. Learning curves of 2 interventionalists who performed 86.5% of PAEs were analyzed.ResultsTortuosity of pelvic arteries was classified as mild in 25 (34.2%) patients median age 64 years, moderate in 40 (54.8%) patients median age 69 years, and severe in 8 (11.0%) patients median age 70 years (mild vs moderate, P = .002; mild vs severe, P = .019); median fluoroscopy times were 24, 36, and 46 minutes (P = .008, P = .023); median contrast volumes were 105, 122.5, and 142 mL (P = .029, P = .064); and bilateral PAE rates were 84.0%, 77.5%, and 62.5% (P = .437), respectively. PA origin from superior vesical artery was most frequent (27.5%) and showed higher dose area product (median 402.4 vs 218 Gy ∙ cm², P = .033) and fluoroscopy time (median 42.5 vs 27 min, P = .01) compared with PA origin from obturator artery, which was least frequent. Interventionalist experience revealed significant impact on procedure times (median 159 vs 130 min, P = .006).ConclusionsTortuosity of pelvic arteries was more frequent in older patients and predicted worse technical outcomes of PAE. PA origin from obturator artery was associated with lower dose area product and fluoroscopy time, especially compared with PA origin from superior vesical artery. Interventionalist experience showed significant influence on technical outcome.     

Are patient-reported outcome measures biased by method of follow-up? Evaluating paper-based and digital follow-up after lumbar fusion surgery

Background Context

Long-term follow-up of patient-reported outcome measures (PROM) is essential in both modern spinal care and research. Lack of time and staff are commonly reported barriers to implementing long-term follow-up of PROM. Automated and digital follow-up systems for PROM collection are seeing widespread use, yet their validity and comparative effectiveness have never been evaluated.

Self-representations on social media. Reproducing and challenging discourses on disability

This article examines self-representations in a social media campaign against the discrimination of people with disabilities. We focus specifically on how these representations are related to various narratives and discourses, and in what ways the representations either adhere to or challenge normative discourses, or whether they offer counter-discourses. Considering that our cultural assumptions are influenced by the representations we are exposed to, we also discuss the possible potential of self-representations for the audience of the campaign. The empirical material consists of a digital activism campaign conducted on Instagram in Sweden that was constructed through self-representations (photos and short texts). The study combines discourse analysis and visual analysis with focus on how the persons present themselves in the campaign, how disability is mentioned and/or displayed, and how a presentation adheres to or challenges a model of understanding disability, such as the medical or social models. We found a diverse set of claims, all with the common goal of acknowledging discrimination, in order to make it visible and bring about change. The narratives identified indicate a variety of strategies for understanding disability and various styles that people adopt to relate to established discourses on disabilities. Through this campaign, the bloggers could find and provide support, but they also took the stage by requesting that the audience listen. The campaign examined in this study can be further understood as an effort and a step towards increased visibility and politicization of disability.     

脊椎转移瘤增强减影MR成像

目的评估增强减影在脊椎转移瘤MR I中的应用价值。方法50例脊椎转移瘤病人进行MR I增强扫描,对比剂采用Gd-DTPA(0.1 mmol/kg),然后用T1W I增强后的图像与增强前的图像进行减影。通过对比噪声比(CNR)、信噪比(SNR)以及肿瘤边界清晰程度的比较,对MR I减影与否进行评估。结果MR I对比增强减影图像比传统的T1W I增强图像显示更清晰、更直观。所有脊椎转移瘤图像MR I减影的CNR和SNR比常规T1W I增强图像的CNR和SNR高。MR I减影CNR为155.05±24.73(x±SD),常规T1W I增强图像的CNR为11.11±14.26(t=35.65,Ρ<0.001)。MR I减影SNR为192.82±32.89(x±SD),常规T1W I增强图像的SNR为46.03±28.22(t=23.95,Ρ<0.001))。MR I对比增强减影图像比传统的T1W I增强图像能更好地显示脊椎转移瘤的边界和侵犯情况(2χ=29.34,Ρ<0.005)。结论MR I增强减影为探查和评估脊椎转移瘤提供了一个新的诊断方法。