Percutaneous Mechanical Atherothrombectomy Using the Rotarex Device in Acute Ischemic Disease of Lower Limbs: A China Retrospective Multicenter Study on 186 Patients.

BACKGROUND: To evaluate the efficacy and safety of the Rotarex mechanical thrombectomy device in treating acute lower extremity arterial ischemia and to explore the appropriate indication of the Rotarex device. METHODS: A retrospective analysis was performed in 186 patients with acute lower extremity arterial ischemia treated with the Rotarex mechanical thrombectomy device from April 2015 to March 2020 in three vascular surgery centers of Tianjin. As per the comprehensive judgment of the etiology, onset time, imaging of ultrasonography (US) and angiography, and findings during treatment, the patients were divided into the embolization group (69 cases), thrombosis group (primary artery stenosis with thrombosis; 86 cases), and restenosis group (stent restenosis with thrombosis; 31 cases). The primary study outcomes included the success rate of Rotarex mechanical thrombectomy device alone, percutaneous transluminal angioplasty (PTA), stent, catheter-directed thrombolysis (CDT) auxiliary rate, target vessel patency rate, and freedom from clinically driven target lesion revascularization rate (f-CD-TLR). The secondary study outcomes included intraoperative distal arterial embolization, postoperative 30-day bleeding, and deterioration of renal function, amputation, and mortality. RESULTS: The success rate of Rotarex mechanical thrombectomy device alone in the embolization group (44.93%) was significantly higher than that in the thrombosis group (13.95%) and restenosis group (0%) (P < 0.01). The PTA auxiliary rate in the embolization group (26.09%) was significantly lower than that in the thrombosis group (72.09%) and restenosis group (100%) (P < 0.01). The stent implantation rates in the embolization group and restenosis group (11.60% and 33.30%, respectively) were significantly lower than that in the thrombosis group (72.09%) (P < 0.01). There were no significant differences in the CDT auxiliary rate, distal arterial embolization, hemorrhage, renal function deterioration, amputation rate, and mortality among the three groups (P > 0.05). The primary patency at 3 months, 6 months, and 12 months postoperatively was 98.6%, 98.6%, and 84.3% in the embolization group, 96.4%, 89.5%, and 74.9% in the thrombosis group, and 93.2%, 84.7%, and 67.5% in the restenosis group, respectively (P < 0.01). The f-CD-TLR at 12 months postoperatively was 88.9% in the embolization group, which was higher than 77.8% in the thrombosis group and 67.5% in the restenosis group (P < 0.01). CONCLUSIONS: The Rotarex mechanical thrombectomy device is a minimally invasive, safe, and effective treatment option for acute lower extremity arterial ischemia, particularly acute arterial embolization. For acute thrombosis secondary to primary artery stenosis and in-stent restenosis, Rotarex device can effectively reduce the thrombus burden and create favorable conditions for other concurrent interventions.

Primary Aortoduodenal Fistula in a Patient With Multiple Duodenal Diverticula.

A 67-year-old man with massive hematemesis was transferred to the emergency unit of our hospital. The patient was diagnosed with primary aortoduodenal fistula (PADF) based on the CT findings. Upon emergent exploration, multiple duodenal diverticula were found and in situ abdominal aortic aneurysm (AAA) repair using polytetrafluoroethylene (PTFE) graft was performed. The third and fourth parts of the duodenum with multiple duodenal diverticula and the origin of jejunum were excised, and end-to-side duodenojejunostomy was performed. The patient was discharged on the 38th postoperative day with another 6 month oral antibiotic treatment. The duodenal diverticula may be the cause for PADF.

Fenestrated Thoracic Endovascular Aortic Repair Using Physician Modified Stent Grafts for Acute Type B Aortic Dissection with Unfavourable Landing Zone.

OBJECTIVES: The aim was to evaluate the early results of fenestrated thoracic endovascular aortic repair (fTEVAR) using physician modified stent grafts (PMSGs) to revascularise aortic branches for acute type B aortic dissection (ABAD) with unfavourable proximal landing zone. METHODS: Twenty consecutive patients who underwent fenestrated TEVAR using PMSGs between November 2015 and December 2016 were retrospectively reviewed. Pre-, intra-, and post-operative clinical data were recorded. RESULTS: The median patient age was 53 years (range, 18-83 years), and 16 of the 20 (80%) patients were men. Indications were complicated ABAD with unfavourable proximal landing zones, including inadequate proximal landing zone (n = 4), retrograde dissection extending to the left subclavian artery (LSA) (n = 13), and retrograde haematoma involving the LSA (n = 3). Twenty PMSGs (Medtronic Valiant stent grafts, n = 4; Relay thoracic stent grafts, n = 10; Ankura thoracic stent grafts, n = 6) were deployed. One LSA fenestration was created in 19 patients, and one LSA fenestration combined with a left common carotid artery (LCCA) scallop was created in one patient. Branch stents consist of a covered stent for the LSA (n = 7), an uncovered stent for the LSA (n = 14), and an uncovered stent for the LCCA (n = 1). The median duration for stent graft modifications was 40 min (range 30-60 min). The mean interval between symptom onset and treatment was 5 ± 3 days (range, 1-10 days). The initial technical success rate was 90% (18 of 20). Partial coverage of the LCCA in one patient resolved after uncovered chimney stent implantation in the LCCA. Type III endoleak between the LSA covered stent and the PMSG occurred in this patient 1 week post fTEVAR and resolved after re-intervention with deployment of an Amplatzer occluder device across the site of the leak. A chimney stent was deployed to solve the misalignment of the LSA in another patient. The mean operation time was 101 ± 48 min, and fluoroscopy time was 24 ± 16 min. There were no in hospital deaths and no peri-operative neurological complications. The median length of stay was 9 ± 6 days (range, 5-26 days). One patient had a left brachial artery (LBA) pseudoaneurysm at the puncture site that required open repair. One patient presented renal deterioration post-operatively and recovered uneventfully after conservative therapy. All patients survived at a mean follow-up of 6.95 months (range, 2-14 months). During follow-up, no post-operative complications occurred and all target vessels remained patent. No fenestration related Type I or III endoleaks were observed. CONCLUSIONS: fTEVAR using PMSGs may be a viable alternative for patients who present with ABAD without healthy proximal landing zones and who are unable to wait for a custom made fenestrated device.

Outcomes of single physician-modified fenestrated stent grafts for endovascular repair of thoracic aortic lesions involving the distal aortic arch.

OBJECTIVES: Our goal was to evaluate the outcomes of fenestrated thoracic endovascular aortic repair of thoracic aortic lesions involving the distal aortic arch using single physician-modified stent grafts. METHODS: This single-centre, retrospective study included 58 consecutive patients (mean age, 57 ± 14 years; 11 women) who underwent fenestrated thoracic endovascular aortic repair for thoracic aortic pathologies involving the distal aortic arch using single physician-modified stent grafts between November 2015 and December 2018. Indications included complicated acute type B dissection or intramural haematoma with an unfavourable proximal landing zone (n = 49), type Ia endoleak subsequent to thoracic endovascular aortic repair due to acute type B dissection (n = 1) and distal arch degenerative aneurysms <15 mm from the left subclavian artery (n = 8). RESULTS: The technical success rate was 94.8%. The 30-day mortality was 1.7%, and the perioperative ischaemic stroke rate was 1.7%. The incidence of perioperative complications was 10.3%. At a mean follow-up of 26.3 months (range, 7-44), all target vessels were patent. All-cause mortality was 5.2%. Estimated 1-, 2- and 3-year survival was 98.3 ± 1.7%, 96.4 ± 2.5% and 93.2 ± 3.9%, respectively. CONCLUSION: The single fenestrated stent graft technique is feasible and effective for endovascular repair of thoracic aortic pathologies involving the distal aortic arch.

One-stage supraclavicular hybrid procedure for type B aortic dissection involving three rare anatomical anomalies: a case report and literature review.

Managing type B aortic dissection (TBAD) involving Kommerell's diverticulum (KD), aberrant right subclavian artery (ARSA), and isolated left vertebral artery (ILVA), is extremely challenging. As treatment, we described a one-stage hybrid technique combined with thoracic endovascular aortic repair (TEVAR) with open surgery through a supraclavicular incision. A 57-year-old man with TBAD and the three anomalies successfully underwent hybrid TEVAR. A side-to-side artificial bypass between the ARSA and the right common carotid artery was established through a right supraclavicular incision before TEVAR. The release of the stent-graft was designed from the distal aortic ostium to the left common carotid artery (LCCA) to cover the ILVA, ARSA, and left subclavian artery (LSA). Then, the ILVA and LSA were transposed to the LCCA through a left supraclavicular incision. Intraoperative angiography confirmed complete false lumen exclusion and KD, with all branches patent and without endoleaks. Computed tomography angiography 7 days and 1 year postoperatively demonstrated well-perfused ARSA, LSA, and ILVA, and a fully expanded stent-graft with no endoleaks, migration, disconnection, or stenosis. TBAD involving KD, ARSA, and ILVA in one case is rare. This is the first report to treat this pathology with a one-stage supraclavicular hybrid procedure.

Fenestrated Thoracic Endovascular Aortic Repair Using Physician-Modified Stent Grafts (PMSGs) in Zone 0 and Zone 1 for Aortic Arch Diseases.

PURPOSE: To evaluate the outcomes of fenestrated thoracic endovascular aortic repair (f-TEVAR) using physician-modified stent grafts (PMSGs) in zone 0 and zone 1 for aortic arch diseases. METHODS: f-TEVAR using PMSGs in Z0 and Z1 was performed on ten high-risk patients for open surgery from November 2015 to September 2017. Indications were complicated acute type B dissection (ABAD) with retrograde dissection involving the mid-arch (n = 1), distal arch aneurysms (n = 3), mid-arch aneurysms of the inner arch curvature (n = 3) and penetrating aortic ulcer located in the mid- or proximal arch (n = 3). Pre-, intra- and postoperative clinical data were recorded. RESULTS: The median patient age was 61 (range 45-81) years, and 9 (90%) patients were men. Ten PMSGs (Medtronic Valiant stent grafts, n = 1; Relay thoracic stent grafts, n = 4; Cook TX2 device, n = 5) were deployed. PMSGs were deployed from Z0 and Z1 in 5 and 5 patients, respectively. Double small fenestrations for the left subclavian artery (LSA) and the left common carotid artery (LCCA), respectively, were created in 3 patients. Triple small fenestrations for the innominate artery (IA), the LCCA and the LSA, respectively, were created in 2 patients. One large fenestration for both the IA and the LCCA combined with one small fenestration for the LSA was created in 3 patients. One large fenestration for the LCCA combined with one small fenestration for the LSA was created in 2 patients. Posterior diameter-reducing ties were added to all the devices except to one Valiant stent graft. All but 2 patients underwent elective procedure. Median duration for stent graft modifications was 105 (range 90-125) min. The technical success rate was 90%. Overall mortality was 10% (1/10). One patient died of sudden cardiac arrest intraoperatively after the deployment of the PMSG and all the supra-aortic branch stents. Mean operative time was 106.0 ± 43.0 min, and fluoroscopy time was 30.6 ± 22.9 min. There were no type I or type III endoleaks, perioperative neurological complications or spinal cord ischemia. Median length of stay was 8 (range 4-35) days. Nine patients survived at mean 13.3 (range 6.0-19.0) months follow-up. Retrograde dissection occurred in one patient of Z0 group 40 days post-f-TEVAR and resolved after open repair. During follow-up, all target vessels remained patent without fenestration-related type I or III endoleaks. CONCLUSIONS: f-TEVAR using PMSGs in Z0 and Z1 for the treatment of aortic arch diseases in high-risk patients is feasible in the hands of experienced operators.

Treatment of aortic dissecting aneurysm involving visceral arteries with multi-layer bare stents.

OBJECTIVE: Aortic dissecting aneurysms involving visceral arteries are difficult for clinical treatment. This study aimed to explore the clinical efficacy and safety of multi-layer bare stents technique in the treatment of aortic dissecting aneurysms involving visceral arteries. METHOD: The clinical data of 16 patients of aortic dissecting aneurysm involving visceral artery treated with multi-layer bare stents technique from March 2013 to March 2017 in Tianjin Medical University General Hospital were retrospectively analyzed. To explore the clinical efficacy, the number of stents applied, postoperative aortic dissecting thrombosis and postoperative cumulative branch arterial patency of the16 patients. RESULTS: The operations of the 16 patients were successfully completed without peri-operative death cases. The 16 patients were implanted with 39 bare stents with an average of 2.44 per person. There were 2 cases with 1 stent, 8 cases with 2 stents and 7 cases with 3 stents. One month after the operation, CTA showed complete thrombosis in the arterial dissection in 4 cases (25.0%), partial thrombosis in 12 cases (75.0%); CTA showed that celiac artery, left and right renal arteries, and superior mesenteric artery were all unobstructed. There were 4 cases (25.0%) of dissecting artery with reduced diameter, 12 patients (75.0%) without changes in the diameter, and no diameter expanding cases. CONCLUSION: The treatment for aortic dissecting aneurysm involving the visceral arteries using multi-layer bare stents technique is safe and reliable with a higher patency rate of postoperative accumulated branch arteries.

Endovascular treatment of primary mycotic aortic aneurysms: a 7-year single-center experience.

Objective This study was performed to assess the efficacy and outcome of endovascular aneurysm repair (EVAR) for treatment of primary mycotic aortic aneurysms (PMAAs). Methods Fourteen consecutive patients who presented with PMAA from April 2010 to July 2017 were retrospectively reviewed. Preoperative, intraoperative, and postoperative clinical data were recorded, and late infection-related complications and long-term survival were assessed. Results The aneurysms were located in the abdominal aorta in 10 patients and in the left common iliac artery in 4 patients. Positive microbial cultures were found in 12 patients, including Salmonella species in 11 and Streptococcus in 1. The remaining two patients had negative culture results. Ten patients received preoperative antibiotics before elective EVAR for 7 ± 9 days after admission. Four patients who underwent emergent EVAR due to ruptured aneurysms were given their first dose of antibiotics before EVAR. Three patients underwent surgical drainage, and six underwent percutaneous drainage within 30 days after EVAR. No death occurred within 30 days of the initial procedure. The mean follow-up was 34.8 (range, 3-84 months). One patient underwent re-intervention to resolve obstruction of the iliac/femoral artery 5 months postoperatively. Relapse of infection occurred in six patients (42.8%) during follow-up; infection-related death occurred in three of these patients. The other patients recovered with either conversion to open radical surgery or medical therapy. The actuarial 7-year survival after EVAR was 75.7%. Conclusions EVAR and aggressive antibiotic therapy might be suitable for PMAAs. Favorable results may be typical for infection caused by Salmonella.

Treatment for thoracoabdominal aortic aneurysm by fenestrated endovascular aortic repair with physician-modified stent graft.

Despite being widely used for several years, the endovascular aortic repair (EVAR) of a thoracoabdominal aneurysm (TAAA) remains challenging, particularly the revascularization of the abdominal aortic visceral branches. A 66-year-old male was admitted to hospital with abdominal bloating and pain. Computed tomographic angiography (CTA) confirmed a Crawford type III TAAA from the distal descending aorta to the suprarenal abdominal aorta that involved the celiac axis, accompanied with an occlusion of the left subclavian artery. Fenestrated-EVAR was performed successfully and 1 week later CTA showed a type III endoleak, which had resolved 3 months later, without stent migration or visceral artery occlusion. In this present case, the surgeons preferred to perform the procedure in three surgical stages, postponing the deployment of a covered stent in the CA fenestration to provide additional time for the development of collateral circulation to the spinal cord as a possible means of preventing postoperative paraplegia.

Influential factors and formation of extrahepatic collateral artery in unresectable hepatocellular carcinoma.

AIM: To analyze the influence factors and formation of extrahepatic collateral arteries (ECAs) in unresectable hepatocellular carcinoma (HCC) with or without chemoembolization. METHODS: Detailed histories of 35 patients with 39 ECAs of HCC and images including computerized tomography scan, digital subtraction angiography were reviewed carefully to identify ECAs of HCC, ECAs arising from, and anatomic location of tumors in liver. Tumor sizes were measured, and relations of ECAs with times of chemoembolization, tumor size, and the anatomic tumor location were analyzed. Complications were observed after chemoembolization through ECAs of HCC with different techniques. RESULTS: Influence factors of formation of ECAs of HCC included the times of repeated chemoembolization, the location of tumors in liver, the tumor size and the types of chemoembolization. ECAs in HCC appeared after 3-4 times of chemoembolization (17.9%), but a higher frequency of ECAs occurred after 5-6 times of chemoembolization (56.4%). ECAs presented easily in peripheral areas (71.8%) of liver abutting to the anterior, posterior abdominal walls, the top right of diaphragm and right kidney. ECAs also occurred easily after complete obstruction of the trunk arteries supplying HCCs or the branches of proper hepatic arteries. Extrahepatic collaterals of HCC originated from right internal thoracic (mammary) artery (RITA, 5.1%), right intercostal artery (RICA, 7.7%), left gastric artery (LGA, 12.8%), right inferior phrenic artery (RIPA, 38.5%), omental artery (OTA, 2.6%), superior mesenteric artery (SMA, 23.1%), and right adrenal and renal capsule artery (RARCA, 10.3%), respectively. The complications after chemoembolization attributed to no super selective catheterization. CONCLUSION: The formation of ECAs in unresectable HCC is obviously correlated with multiple chemoembolization, tumor size, types of chemoembolization, anatomic location of tumors. Extrahepatic collaterals in HCC are corresponding to the tumor locations in liver.

Hybrid technique to treat superior mesenteric artery occlusion in patients with acute mesenteric ischemia.

Acute mesenteric ischemia is a condition with a high mortality rate. In the present study, a novel hybrid technique for the treatment of acute mesenteric ischemia was investigated. The retrospective study population included six patients, of which five were male and one was female, with a mean age of 69 years (age range, 59-73 years). The hybrid technique involved isolating the superior mesenteric artery (SMA) for cannulation and subsequently performing a fluoroscopically-assisted embolectomy, retrograde balloon angioplasty and stenting. Intra-arterial, catheter-directed thrombolysis was performed if required. Bowels showing evident necrosis were resected, while ischemic bowels with the potential for recovery were left for 48 h before being re-examined during the second-look surgery. Retrograde open mesenteric stenting (ROMS) was successfully performed on two patients without bowel resection. Four patients were successfully treated by intra-arterial catheter-directed thrombolysis following recanalization of the SMA, and the ischemic bowels had exhibited a full recovery by the second-look operation. Three patients underwent a massive bowel resection, but did not develop short bowel syndrome. Two patients developed acute renal failure, one of which recovered after 10 days of dialysis, while the other patient succumbed to acute renal failure. In the five surviving patients, the SMA remained patent for the duration of the follow-up period. Therefore, ROMS was shown to be a viable alternative procedure for emergent SMA revascularization. In addition, intra-arterial catheter-directed thrombolysis following recanalization of the SMA was demonstrated as an alternative technique for inhibiting necrosis in bowels with acute mesenteric ischemia.

Interventional and synthetic therapy of advanced hepatocellular carcinoma.

OBJECTIVE: To evaluate the clinical efficacy of interventional therapy in the treatment of hepatocellular carcinoma (HCC). METHODS: Thirty-three patients with HCC were synthetically treated by systematic measures. Among them, percutaneous port-catheter system (PCS) implantation via the femoral artery was performed in 21 cases. Patients with haemorrhage were treated with prothrombin complex concentrate and fibroraas, and patients with hepatic encephalopathy by branched-chain amino acids and arginine. RESULTS: All indwelling catheters of PCS were patent and no catheter tip dislocations were observed. Of 33 patients with advanced HCC, the mean survival rate was 20.1 months and 12 (36%) patients survived more than 2 years. CONCLUSION: Patients with advanced HCC were treated by synthetic measures. Survival was prolonged, quality of life was improved significantly, and the effectiveness of interventional therapy was further improved.

Treatment of aortic dissecting aneurysm involving visceral arteries with multi-layer bare stents

SUMMARY OBJECTIVE: Aortic dissecting aneurysms involving visceral arteries are difficult for clinical treatment. This study aimed to explore the clinical efficacy and safety of multi-layer bare stents technique in the treatment of aortic dissecting aneurysms involving visceral arteries. METHOD: The clinical data of 16 patients of aortic dissecting aneurysm involving visceral artery treated with multi-layer bare stents technique from March 2013 to March 2017 in Tianjin Medical University General Hospital were retrospectively analyzed. To explore the clinical efficacy, the number of stents applied, postoperative aortic dissecting thrombosis and postoperative cumulative branch arterial patency of the16 patients. RESULTS: The operations of the 16 patients were successfully completed without peri-operative death cases. The 16 patients were implanted with 39 bare stents with an average of 2.44 per person. There were 2 cases with 1 stent, 8 cases with 2 stents and 7 cases with 3 stents. One month after the operation, CTA showed complete thrombosis in the arterial dissection in 4 cases (25.0%), partial thrombosis in 12 cases (75.0%); CTA showed that celiac artery, left and right renal arteries, and superior mesenteric artery were all unobstructed. There were 4 cases (25.0%) of dissecting artery with reduced diameter, 12 patients (75.0%) without changes in the diameter, and no diameter expanding cases. CONCLUSION: The treatment for aortic dissecting aneurysm involving the visceral arteries using multi-layer bare stents technique is safe and reliable with a higher patency rate of postoperative accumulated branch arteries.

RESUMO Objetivo: Aneurismas dissecantes da aorta envolvendo artérias viscerais são de difícil tratamento clínico. O objetivo deste estudo foi explorar a eficácia e segurança clínica da técnica de stents multicamadas não farmacológicos para o tratamento de aneurismas dissecantes da aorta envolvendo artérias viscerais. Métodos: Foi feito um estudo retrospectivo usando os dados de 16 pacientes com aneurisma dissecante da aorta envolvendo artérias viscerais e tratados com stents multicamadas não farmacológicos de março de 2013 a março de 2017, do Hospital da Escola de Medicina da Universidade de Tianjin. Foram analisados nos 167 pacientes: a eficácia clínica, o número de stents aplicados, trombose dissecante da aorta no pós-operatório e patência cumulativa pós-operatória do ramo arterial. Resultados: As operações dos 16 pacientes foram concluídas com sucesso sem nenhum óbito perioperatório. Os 16 pacientes receberam 39 stents não farmacológicos, com uma média de 2,44 por indivíduo. Houve 2 casos com 1 stent, 8 com 2 stents, e 7 com 3. Um mês após a operação, a ATC mostrou trombose completa da dissecção arterial em 4 casos (25,0%) e trombose parcial em 12 casos (75%). Também mostrou que a artéria celíaca, as artérias renais direita e esquerda e a artéria mesentérica superior estavam todas desobstruídas. Houve 4 casos (25,0%) de artéria dissecante com diâmetro reduzido, 12 (75,0%) pacientes sem alteração no diâmetro, e nenhum caso de aumento de diâmetro. Conclusão: O tratamento para aneurisma dissecante da aorta envolvendo artérias viscerais com a técnica de stents não farmacológicos multicamadas é seguro e confiável, com uma taxa mais alta de patência de ramos arteriais acumulados no pós-operatório.

The effect of short-term intra-arterial delivery of paclitaxel on neointimal hyperplasia and the local thrombotic environment after angioplasty.

PURPOSE: To evaluate the effects of short-term intra-arterial delivery of paclitaxel on neointimal hyperplasia and the local thrombotic environment after angioplasty. METHODS: An experimental common carotid artery injury model was established in 60 rats, which were divided into experimental groups (40 rats) and controls (20 rats). Local intra-arterial administration of paclitaxel was applied at 2 doses (90 and 180 µg/30 µl), and the effects of short-term delivery of paclitaxel on neointimal hyperplasia and the expression of tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (t-PA) were evaluated at days 15 and 30 by hematoxylin and eosin staining and immunohistochemistry. RESULTS: At 15 and 30 days after injury, neointimal thickness and area, the ratio of intimal area to medial area and the stenotic rate were all significantly decreased in the group provided the high concentrations (180 µg/30 µl) of paclitaxel for 2 min or 10 min and in the group provided the low concentration (90 µg/30 µl) of paclitaxel for 10 min (p < 0.05). At 30 days after injury, there were no significant changes in TF expression among all experimental groups. PAI-1 expression increased in the neointima of the high concentration 10 min group (p < 0.05), while t-PA expression decreased in the neointima of the high concentration 2 min group (p < 0.05). CONCLUSION: In the rat common carotid artery injury model, the short-term delivery of paclitaxel could effectively inhibit neointimal hyperplasia in the long term, with very little influence on the local expression of TF and PAI-1.

Kidney segmentation in CT sequences using graph cuts based active contours model and contextual continuity.

PURPOSE: Accurate segmentation of renal tissues in abdominal computed tomography (CT) image sequences is an indispensable step for computer-aided diagnosis and pathology detection in clinical applications. In this study, the goal is to develop a radiology tool to extract renal tissues in CT sequences for the management of renal diagnosis and treatments. METHODS: In this paper, the authors propose a new graph-cuts-based active contours model with an adaptive width of narrow band for kidney extraction in CT image sequences. Based on graph cuts and contextual continuity, the segmentation is carried out slice-by-slice. In the first stage, the middle two adjacent slices in a CT sequence are segmented interactively based on the graph cuts approach. Subsequently, the deformable contour evolves toward the renal boundaries by the proposed model for the kidney extraction of the remaining slices. In this model, the energy function combining boundary with regional information is optimized in the constructed graph and the adaptive search range is determined by contextual continuity and the object size. In addition, in order to reduce the complexity of the min-cut computation, the nodes in the graph only have n-links for fewer edges. RESULTS: The total 30 CT images sequences with normal and pathological renal tissues are used to evaluate the accuracy and effectiveness of our method. The experimental results reveal that the average dice similarity coefficient of these image sequences is from 92.37% to 95.71% and the corresponding standard deviation for each dataset is from 2.18% to 3.87%. In addition, the average automatic segmentation time for one kidney in each slice is about 0.36 s. CONCLUSIONS: Integrating the graph-cuts-based active contours model with contextual continuity, the algorithm takes advantages of energy minimization and the characteristics of image sequences. The proposed method achieves effective results for kidney segmentation in CT sequences.

Percutaneous transluminal angioplasty (PTA) alone versus PTA with balloon-expandable stent placement for short-segment femoropopliteal artery disease: a metaanalysis of randomized trials.

PURPOSE: To evaluate and compare the results of percutaneous transluminal angioplasty (PTA) and stent placement to treat femoropopliteal artery occlusive disease. MATERIALS AND METHODS: Published data of randomized clinical trials comparing the results of PTA and stent placement for femoropopliteal artery occlusive disease were analyzed. Proportions were combined, and the odds ratio (OR) with its 95% CI was used as the effect size estimate. RESULTS: Seven studies published in 1999 or later (614 limbs in 519 patients) were included in this metaanalysis, in which 323 limbs underwent PTA and 291 limbs underwent PTA followed by balloon-expandable stent placement. In the combined results of PTA versus PTA plus stent placement, a significant difference in primary patency at 6 months (OR, 0.47; 95% CI, 0.27-0.84; P < .05) was found, but no significant difference could be found in primary patency at 12 months (OR, 1.27; 95% CI, 0.87-1.86; P > .05) or 24 months (OR, 1.22; 95% CI, 0.81-1.82; P > .05) or in secondary patency at 12 months (OR, 1.34; 95% CI, 0.78-2.30; P > .05). CONCLUSIONS: In the treatment of femoropopliteal artery occlusive disease (< or =10 cm), higher primary patency rates can be expected at 6 months with PTA followed by implantation of balloon-expandable stents versus PTA alone, but PTA with stent placement does not produce better long-term primary results and secondary patency rates than PTA alone.