The percutaneous learning curve of 3rd generation minimally-invasive Chevron and Akin osteotomy (MICA)

BackgroundMinimally-invasive Chevron and Akin osteotomy (MICA) represents the third-generation percutaneous hallux valgus surgery which is characterized by an extra-articular osteotomy, stable internal fixation and a high potential for correction. Compared to other percutaneous techniques of the foot, MICA is generally regarded as an advanced and demanding surgical procedure with a flat learning curve. The aim of this study is to analyze a single-surgeons experience with his first 50 consecutive MICA procedures.MethodsBetween May 2018 and February 2021, 50 consecutive MICA procedures performed by the author with the "K-wires-First technique" were prospectively analyzed focusing on surgery duration, number of fluoroscopies, correction results and surgery-associated complications. A modification of the original MICA technique as described by its inaugurators Redfern and Vernois allows the use of a standard-sized C-arm and aims to reduce revison rates and conversion to open surgery by placing the guidewires prior to performing the osteotomy.ResultsThe average surgery time for all MICA procedures was 46.8 min (SD 12.1, range 31–90 min). The average amount of fluoro shots required to perform MICA was n = 126.6 (SD 40.8, range 65–231). Comparing the preoperative and 6-week postoperative radiographs, the IMA decreased after MICA by a mean of 10.8° from 16.2° to 5.4° and the HVA by a mean of 22.1° from 30.6° to 8.5°. One case required intraoperative conversion to open hallux correction. There were 4 feet in three patients with secondary screw removal of the Chevron fixation due to prominent proximal screw tips.ConclusionsAlthough the learning curve of 3rd generation MICA is flat and requires specific training and intensive practice, the rate of complications is not elevated compared to other percutaneous hallux valgus techniques. Strict adherence to the principles of 3rd generation MICA with stable fixation and meticulous intraoperative control of each surgical step helps to reduce surgery-associated complications. The learning curve showed a continous improvement in regard to surgery time and use of fluoroscopy. After 40 procedures, the surgery time consistently dropped under 45 min and required less than 100 fluoro-shots. The modified surgical technique may help reduce Chevron screw mal-positioning when using large C-arm fluoroscopy for this procedure.     

急性胆源性胰腺炎合并急性重症胆管炎处理策略

急性胆源性胰腺炎合并急性重症胆管炎病情凶险，病死率高。早期诊断，在内科治疗的同时，积极手术，合理选择内镜胆道引流、经皮经肝胆道引流、开放胆总管探查等治疗策略，以期阻止或延缓病情进展，降低并发症发生率及病死率。     

Outcomes of Fluoroscopy-Guided Percutaneous High Ligation of the Great Saphenous Vein Combined With Foam Sclerotherapy for Symptomatic Great Saphenous Veins

PurposeTo evaluate the effectiveness and safety of fluoroscopy-guided percutaneous high ligation (FPHL) combined with fluoroscopy-guided foam sclerotherapy (FGFS) to treat varicose veins of the great saphenous veins (GSVs).Materials and MethodsThis was a retrospective study of 113 patients (mean age, 62.1 ± 10.8 years; 60 men) with varicose veins of the GSVs (133 limbs) that were treated with FPHL combined with FGFS between April 1 and October 31, 2019. Demographic and clinical data were collected from these patients before the FPHL procedure, after which FGFS was performed. The preterminal GSV was ligated percutaneously by a percutaneously-positioned polypropylene ligature under fluoroscopic guidance. The outcome of ligation was confirmed by venography. Then, foam sclerotherapy was performed under fluoroscopy. At 1-year follow-up, GSV occlusion was evaluated by ultrasound. The venous clinical severity scores (VCSSs) were compared between the preoperative and 1-year follow-up periods.ResultsThe technical success rate was 100% (133 limbs). Complete 12-month follow-up was available for 112 limbs (84.2%) and 103 of these limbs (92.0%) remained occluded during this period. The VCSS improved from 4.71 ± 2.15 to 0.74 ± 0.60 (V = 6328, P < .001). During follow-up, there were 16 limbs with thrombophlebitis and 38 limbs with saphenous junction pain; these events were alleviated within 2 weeks of the procedure. There was no deep venous thrombosis or other severe adverse events.ConclusionsFPHL combined with FGFS to treat varicose veins in the GSVs achieved an occlusion rate of 92% and improved the clinical symptoms within 1 year; this minimally-invasive procedure was safe and effective.     

专病护理的个案管理模式在行PTCD的梗阻性黄疸病人中的应用效果

目的:探讨专病护理的个案管理模式在行经皮肝穿刺胆管引流(PTCD)术的梗阻性黄疸病人中的应用效果。方法:选取2017年1月—2017年12月和2018年2月—2018年12月就诊于郑州大学第一附属医院介入科一病区且首次诊断为梗阻性黄疸的病人130例为研究对象,按照入院时间的先后顺序分为对照组65例(2017年1月—2017年12月入院),观察组65例(2018年2月—2018年12月入院)。对照组采取常规护理,观察组在对照组基础上采取专病护理的个案管理模式,比较两组病人术后并发症发生情况、疾病知识知晓率及护理满意率。结果:观察组病人疾病知识知晓率及护理满意度明显高于对照组(P<0.05),术后并发症发生率明显低于对照组(P<0.05)。结论:专病护理的个案管理模式应用于行PTCD的梗阻性黄疸病人,明显提高了病人疾病知识知晓率,减少了术后并发症的发生,同时提高了病人的护理满意度。     

Changes in the National Endovascular Management of Femoropopliteal Arterial Disease: An Analysis of the 2011–2019 Medicare Data

PurposeTo describe national trends in the utilization of endovascular approaches (including balloon angioplasty, atherectomy, and stent placement) for the management of femoropopliteal peripheral arterial disease (PAD).Materials and MethodsThe Medicare Physician/Supplier Procedure Summary dataset containing 100% of Part B claims was interrogated for years 2011–2019. The Current Procedural Terminology codes specific for femoropopliteal angioplasty, stent placement, and atherectomy were used to create summary statistics for utilization by year, place of service (hospital inpatient, hospital outpatient, and office-based laboratory), and provider specialty (cardiology, radiology, and surgery).ResultsThe use of atherectomy increased from 34,732 (33%) procedures in 2011 to 75,435 (53%) procedures in 2019, and atherectomy became the dominant treatment strategy for femoropopliteal PAD. The relative utilization of stent placement (36,793 [35%] to 28,899 [20%]) and angioplasty only (34,398 [32%] to 38,228 [27%]) decreased concomitantly from 2011 to 2019. By 2019, the use of atherectomy was twofold higher in office-based laboratories than in the outpatient hospital setting (44,767 and 20,901, respectively). Treatment strategy varied by provider specialty in 2011 when cardiologists used atherectomy most frequently (17,925 [43%]), whereas radiologists used angioplasty alone (5,928 [6%]) and surgeons stented (18,009 [37%]) most frequently. By 2019, all specialties utilized atherectomy most frequently (29,564 [59%] for cardiology, 10,912 [58%] radiology, and 33,649 [47%] surgery).ConclusionsThe national approach to endovascular management of femoropopliteal PAD has changed since 2011 toward an implant-free strategy, including a multifold increase in the use of atherectomy. Discordant rates of atherectomy use between the ambulatory hospital and office-based settings highlight the need for comparative effectiveness studies to guide management.     

Intravascular Ultrasound-Guided Transvenous Biopsy of Abdominal and Pelvic Targets Difficult to Access by Percutaneous Needle Biopsy: Technique and Initial Clinical Experience

PurposeTo report initial clinical experience with intravascular ultrasound (US)-guided transvenous biopsy (TVB) for perivascular target lesions in the abdomen and pelvis using side-viewing phased-array intracardiac echocardiography catheters.Materials and MethodsIn this single-institution, retrospective study, 48 patients underwent 50 intravascular US-guided TVB procedures for targets close to the inferior vena cava or iliac veins deemed difficult to access by conventional percutaneous needle biopsy (PNB). In all procedures, side-viewing phased-array intracardiac echocardiography intravascular US catheters and transjugular liver biopsy sets were inserted through separate jugular or femoral vein access sheaths, and 18-gauge core needle biopsy specimens were obtained under real-time intravascular US guidance. Diagnostic yield, diagnostic accuracy, and complications were analyzed.ResultsIntravascular US-guided TVB was diagnostic of malignancy in 40 of 50 procedures for a diagnostic yield of 80%. There were 5 procedures in which biopsy was correctly negative for malignancy, with a per-procedure diagnostic accuracy of 90% (45/50). Among the 5 false negatives, 2 patients underwent repeat intravascular US-guided TVB, which was diagnostic of malignancy for a per-patient diagnostic accuracy of 94% (45/48). There were 1 (2%) mild, 2 (4%) moderate, and 1 (2%) severe adverse events, with 1 moderate severity adverse event (venous thrombosis) directly attributable to the intravascular US-guided TVB technique.ConclusionsIntravascular US-guided TVB performed on difficult-to-approach perivascular targets in the abdomen and pelvis resulted in a high diagnostic accuracy, similar to accepted thresholds for PNB. Complication rates may be slightly higher but should be weighed relative to the risks of difficult PNB, surgical biopsy, or clinical management without biopsy.     

Nonlinear elasticity of biological basement membrane revealed by rapid inflation and deflation

Basement membrane (BM) is a thin layer of extracellular matrix that surrounds most animal tissues, serving as a physical barrier while allowing nutrient exchange. Although they have important roles in tissue structural integrity, physical properties of BMs remain largely uncharacterized, which limits our understanding of their mechanical functions. Here, we perform pressure-controlled inflation and deflation to directly measure the nonlinear mechanics of BMs in situ. We show that the BMs behave as a permeable, hyperelastic material whose mechanical properties and permeability can be measured in a model-independent manner. Furthermore, we find that BMs exhibit a remarkable nonlinear stiffening behavior, in contrast to the reconstituted Matrigel. This nonlinear stiffening behavior helps the BMs to avoid the snap-through instability (or structural softening) widely observed during the inflation of most elastomeric balloons and thus maintain sufficient confining stress to the enclosed tissues during their growth.

Basement membrane (BM) is a thin layer of fibrous matrix separating cells from the connecting tissues, which functions as a physical barrier and widely exists across multicellular organisms (1). The BM is typically composed of laminins, collagen IV, nidogens, and proteoglycans; laminin and collagen IV are the major components that constitute networks forming the structure of the BM, and nidogen and proteoglycans are associated with the laminin and collagen IV networks. As a physical barrier, the structural and mechanical properties of BM are important in the organization and morphogenesis of tissues and organs as well as in the maintenance of adult functions (2); abnormal BM has been associated with a variety of diseases such as cancer (3). For example, in metastasis, cancer cells must invade through BMs to escape from the primary tumor—a process that causes 90% of cancer-related death (4). Indeed, breaks in BMs can be observed in malignant tumors (5). Thus, mechanical properties of the BM are considered to play important roles in regulating cancer cell invasion (6, 7). Furthermore, as a physical barrier differentiating different parts of tissues, BMs are required to be permeable to small molecules to allow exchange of water and nutrients; the permeability of BM is thus one of the essential kinetic parameters regulating biomolecule exchange and activities of internal cells (8, 9). Given the importance of BMs as a semipermeable barrier maintaining tissue structural integrity, however, their permeability and mechanical properties remain largely unknown, mainly due to the lack of direct measurement methods, especially in situ. This limits our understanding of the physical role of BMs in various physiological and pathological processes such as tumor development and angiogenesis.Determining the mechanical properties of intact BMs in situ is challenging because of their irregular shape, small thickness, and tight connection to the cells inside. Due to these limitations, conventional mechanical tests such as tensile, compression, and bending tests are difficult to be applied to characterize the mechanical behavior of the BM in situ. Instead, previous measurements had been carried out on fragmented BMs isolated from various tissues (e.g., via atomic force microscopy [AFM] indentation) and found that the BM stiffness ranges from ∼kPa to ∼MPa (10–17). In addition, a constitutive relationship is required to extract the material parameters such as elastic modulus and permeability from these experimental measurements. However, like most biological tissues, a reliable constitutive model for the BM is not yet available, causing additional difficulties in obtaining its mechanical parameters from most traditional experiments.In this work, we demonstrate an in situ method to simultaneously measure both the elastic properties and permeability of intact BM in breast cancer spheroid by recording the deflation process of an inflated BM filled with phosphate buffered saline (PBS) by microinjection without requiring complex sample preparation and post-data processing. During the deflation of the BM, its elastic retraction generates a pressure difference to drive the liquid flow through the membrane; the liquid flux can be calculated from the reduction of the intact BM diameter. With the BM thickness measured by transmission electron microscopy (TEM), we can determine the shear modulus, permeability, and diffusivity of the intact BM. Moreover, we find from our measurements that the elasticity of BM is highly nonlinear with a strong strain-stiffening effect. Furthermore, we discuss the possible impact of the strain-stiffening effects of BM on its functions.