Visualization of intervertebral disc degeneration in a cadaveric human lumbar spine using microcomputed tomography.

Gross features of disc degeneration (DD) that are associated with back pain include tears in the anulus fibrosus, structural changes of the endplates, and a collapse of the anulus. The aim of this study is the detailed visualization and microstructural characterization of DD using microcomputed tomography (µCT) and a dedicated image post-processing pipeline. In detail, we investigate a cadaveric spine that shows both types of DD between L1 and L2 and between L2 and L3, respectively. The lumbar spine was obtained from a male donor aged 74 years. The complete specimen was scanned using µCT with an isometric voxel size of 93 µm. Subsequently, regions of interest (ROI) were prepared featuring each complete intervertebral disc including the adjacent endplates. ROIs were then additionally scanned with a voxel size of 35 µm and by means of magnetic resonance imaging. The collapsed endplate of the superior L2 showed explicit signs of an endplate-driven degeneration, including bony endplate failures. In contrast, the intervertebral disc between L2 and L3 showed indications of an annulus-driven DD including severe disc height loss and concentric tears. Using µCT we were able to visualize and quantify bone and cartilage features in DD. We showed that in both cases a suite of structural changes accompanies cartilage degeneration, including microstructural bony adaptions to counteract changes in the biomechanical loading regimen.

Clinical impact of hypogastric artery occlusion in endovascular aneurysm repair.

PURPOSE: To report the long-term results for patients treated with endovascular aneurysm repair and additional embolization and coverage of the hypogastric artery compared with patients treated with simple endovascular aneurysm repair. METHODS: A database of our endovascular aneurysm repair patient cohort was reviewed to find patients with iliac artery aneurysms. The baseline characteristics, the procedural data and the results for patients treated with endovascular aneurysm repair and concomitant hypogastric artery embolization were compared with those for patients treated with simple endovascular aneurysm repair. The results were analyzed for significant differences. RESULTS: Of 106 endovascular aneurysm repair patients treated at our vascular unit from 2001 to 2010, 24 had undergone additional hypogastric artery embolization. The complication rate was significantly increased in this group (12.5% vs. 2.4%; p = 0.041), and the long-term results were significantly poorer. Additional hypogastric artery embolization resulted in late rupture (1.2% vs. 12.5%; p = 0.036), buttock claudication (8.6% vs. 43.8%; p = 0.001) and new onset erectile dysfunction (17.3% vs. 42.9%; p = 0.043). CONCLUSION: Endovascular aneurysm repair with extension of the stent graft to the external iliac artery and embolization of the hypogastric artery was associated with more complications and worse long-term results compared with simple endovascular aneurysm repair.

Experience and outcomes after a decade of endovascular abdominal aortic aneurysm repair: a retrospective study from a community-based single center.

BACKGROUND: The purpose of this study is to report the results of endovascular abdominal aortic aneurysm treatment based on the Zenith stent-graft from a community-based single center over a period of 9 years. METHODS: We retrospectively analyzed immediate technical and clinical results as well as long-term outcomes in patients treated with endovascular aneurysm repair between 2001 and 2010. The study was performed in accordance with the recommendations of the ad hoc committee for standardized reporting practice in vascular surgery. RESULTS: A total of 106 patients were treated in a period of 9 years. A Zenith stent-graft was used in 95% of cases. No deaths occurred during the first 30 days postsurgery. The complication rate was 4.7% (n = 5). The overall clinical and technical success rate at 30 days was 93.4%. After a mean follow-up period of 52 months (range, 13-112 months), the overall mortality rate was 25.4%. Aneurysm-related mortality was 2.1%. Rupture of the aneurysm occurred in four cases (4.3%). The final clinical failure rate was 13.8%. During the follow-up period, the mean diameter of the aneurysm decreased from 58.0 to 52.3 mm. However, expansion of the aneurysm was registered in 10 cases. Eleven patients had a primary endoleak, and another 11 secondary endoleaks occurred during the follow-up. The reintervention rate was 16.3%. The main reasons for repeat interventions were iliac limb occlusion (n = 5) and type 3 endoleak/limb disconnection (n = 4). Graft migration occurred in 3% of cases. A negative impact on sexual function after endovascular repair was reported by 20% of patients. CONCLUSION: Endovascular repair is the treatment of choice for high-risk patients. A small but significant number of clinical failures were observed during the long-term follow-up.

Looking for a Learning Curve in EVAR Based on the Zenith Stent Graft.

The purpose of this study was to report the learning curve of endovascular aneurysm repair (EVAR) based on the Zenith stent graft (Cook Medical Inc., Bloomington, IN). In the last 9 years, 101 patients were treated with a Zenith stent graft. To display the learning curve, a cumulative sum (CUSUM) failure analysis curve of the 30-day technical success rate was calculated. For detailed analysis, our EVAR patient cohort was chronologically divided into three groups. Technical and clinical results, basic patient parameters, and procedural data were compared. The CUSUM graph indicated an initial sharp rise within the first 35 cases and a plateau thereafter. The 30-day technical success rate significantly increased from the first to the second group (83 vs. 100%; p = 0.019), as did the primary technical success rate (66 vs. 97%; p = 0.001). EVAR based on the Zenith stent graft required ∼35 cases to reach a stably high rate of short-term technical success.

Treatment of complex arteriosclerotic lesions with nitinol stents in the superficial femoral and popliteal arteries: a midterm follow-up.

PURPOSE: To evaluate the effectiveness of nitinol stents in patients with short, complex lesions in the superficial femoral and popliteal arteries and to assess midterm results. MATERIALS AND METHODS: Self-expandable nitinol stents were implanted in 54 extremities in 44 patients to treat complex stenoses (n = 32) and occlusions (n = 22) in the superficial femoral and popliteal arteries. Follow-up was performed for 5-51 months to evaluate early thrombosis and midterm patency rates. Midterm patency rates were compared between the following: stenoses and occlusions, proximal and distal locations, good and poor runoff, and diabetic patients and nondiabetic patients. All patients underwent clinical investigation and color Doppler sonography after 1 month and 6 months and at 6-month intervals thereafter. If restenosis or stent thrombosis was suspected, intraarterial digital subtraction angiography of the superficial and popliteal arteries was performed. RESULTS: Percutaneous stent implantation was successful in all patients. The mean duration of follow-up was 27 months (range, 5-51 months). No thrombotic occlusion occurred within the first 4 weeks after stent implantation. The primary 3-year patency rate was 76%, and the secondary patency rate was 87%. Three-year primary patency rates were 65% for diabetic patients and 82% for nondiabetic patients. CONCLUSION: In patients with short, complex stenoses and occlusions, implantation of nitinol stents may have a positive impact on midterm results.