We Underutilize the Leg Graft

Once hemodialysis patients have exhausted all option for a permanent vascular access in both upper extremities, they are often relegated at many dialysis centers to permanent catheter dependence with all its attendant complications, including infections, frequent dysfunction, and central vein stenosis. This commentary makes the case that thigh grafts are a far superior alternative to dialysis catheters in many of these patients. Technical graft failure may occur in some patients due to severe femoral artery calcification, but screening for calcification by ultrasound or computerized tomography can reduce the likelihood of a technical failure. Placement of a thigh graft may lead to critical lower extremity ischemia, but preoperative screening for peripheral vascular disease should minimize this possibility. Thigh grafts have comparable secondary patency to that obtained with upper extremity grafts. Finally, although the risk of infection is somewhat higher for thigh grafts than upper extremity grafts, it is still much lower than the risk of catheter‐related bacteremia. In summary, thigh grafts should be used much more frequently in patients without an option for an upper extremity access.     

An evaluation of expanded polytetrafluoroethylene (PTFE) loop grafts in the thigh as vascular access for haemodialysis in patients with access problems.

A total of 21 patients with vascular access problems received 22 PTFE loop grafts in the thigh as vascular access for haemodialysis. Eighteen of 22 grafts supported haemodialysis during the patients' lifetime. Actuarial patient survival was 50% at 2 years with a cumulative graft patency in the survivors of 80.5%. Although early thrombosis has been a problem, no graft has been lost from infection. We feel that these results are encouraging enough to recommend the use of PTFE grafts in the thigh of patients with vascular access problems.     

Calcification score evaluation in patients listed for renal transplantation

Based on native CT scans of the pelvic region using a standardized calcification score, evaluation of iliac vascular calcification was performed between 2008 and 2012 prior to listing for renal transplantation in 205 patients with chronic kidney disease. Vascular calcification showed a decrease from proximal to distal. The difference between the degree of calcification in the common iliac artery and in the external iliac artery was significant (P<.001). Risk factors for total iliac vascular calcification were age, smoking, sex, underlying renal disease, and diabetes. Multivariate analysis revealed age to be the most relevant risk factor (P<.001). The duration of hemodialysis correlated significantly with total iliac vascular calcification. As the introduction of the standardized surgical evaluation protocol, no transplantation has had to be broken off and no early graft loss due to calcification has occurred. Thus, careful scoring of vascular calcification prior to transplantation may be a valuable tool to support surgical decisions and to improve patient safety and outcome in increasingly older transplant recipients.     

The mid-thigh loop arteriovenous graft: patient selection, technique, and results

As patient longevity on hemodialysis has increased, surgeons are increasingly challenged to provide vascular access to patients who have exhausted options for access in the upper extremity. A common operation performed on these patients has been the loop thigh arteriovenous (AV) graft based off the common femoral vessels. However, there are several disadvantages of placing prosthetic grafts in proximity to the groin. Our group has modified the thigh loop AV graft procedure by moving the anastomoses to the mid-superficial femoral artery and vein. The advantage of this location is that it preserves the proximal femoral vessels for graft revision and avoids the node-bearing tissue and overhanging panniculus of the groin. The purpose of this study was to review our technique, patient selection, and experience with the mid-thigh loop AV graft procedure. Between 2001 and 2003, 46 mid-thigh loop AV grafts were placed in 38 patients. Patient hospital, office, and dialysis clinic records were reviewed. The primary and secondary patency for AV grafts in this study by life-table was 40 per cent and 68 per cent at 1 year and 18 per cent and 43 per cent at 2 years. There were 10 infections (21%) requiring graft removal. Four patients underwent subsequent placement of a proximal loop thigh AV graft after mid-thigh graft failure. Patient survival was 86 per cent at 1 year and 82 per cent at 2 years. There were no patient deaths related to thigh graft placement. Our results with the mid-thigh loop AV graft compare favorably with published results for thigh loop AV grafts. The procedure preserves the proximal vasculature, permitting graft revision or subsequent proximal graft placement, and may be associated with fewer infectious complications. The mid-thigh loop AV graft procedure should be considered before placement of a thigh loop AV graft based off the common femoral artery and vein.     

孤立性髂动脉瘤19例诊治经验

目的 探讨孤立性髂动脉瘤(solitary iliac aneurysms,SIA)的诊治方法.方法 回顾性分析1985年1月至2008年1月23年间19例SIA患者的临床资料.其中,男性18例,女性1例,年龄39～77岁,平均(62±7)岁.19例患者中16例行择期动脉瘤切除、人工血管移植,1例行腔内修复术,1例破裂性SIA急诊行动脉瘤切除、人工血管移植,1例破裂性SIA未手术即死亡.结果 19例患者共有30个SIA,其中25个(83.3%)位于髂总动脉,4个(13.3%)位于髂内动脉,1个(3.3%)髂外动脉瘤.11例(57.9%)患者具有多发性动脉瘤,其中9例(47.4%)为双侧髂动脉瘤,另2例合并其他部位的动脉瘤.2例(10.5%)合并动脉闭塞性疾病.2例破裂SIA,1例抢救成功,1例抢救无效死亡.开腹手术的17例患者无围手术期死亡,无盆腔脏器缺血等并发症;1例腔内修复术治疗后无内漏等并发症.术后移植血管通畅,无新发动脉瘤形成早期诊断和治疗SIA非常重要,应通过CTA等方法明确诊断及有否合并多发性动脉瘤或动脉闭塞性疾病.SIA的手术效果良好,术后应长期随访,注意有否吻合口动脉瘤或新生动脉瘤.     

Comparison between externally stented and unstented PTFE vascular grafts

It has been suggested that external stenting of synthetic vascular prosthetic material may improve patency rates in the low flow situation or across joints. This study compared externally stented polytetrafluoroethylene (PTFE) vascular grafts placed across the hip joint in dogs with nonstented PTFE grafts in regard to patency. Twenty animals underwent bilateral common iliac to common femoral artery bypass with proximal ligation of the femoral artery. In each animal one groin was randomly assigned to receive stented PTFE and the other nonstented PTFE. One animal was sacrificed at 2 weeks for graft infection. Nineteen animals received 38 grafts that remained in place 90-120 days. Patency was confirmed with angiography prior to sacrifice. Overall patency was 65 per cent with no significant difference between the two types of graft. Eighteen of 19 dogs (95%) had both the stented and nonstented PTFE grafts either open or closed. It is concluded that intrinsic factors, rather than external graft support, are a more important influence on graft patency in this model.     

Comparison of arteriovenous grafts in the thigh and upper extremities in hemodialysis patients

Placement of a thigh graft is an option in hemodialysis patients who have exhausted all upper extremity sites for permanent vascular access. The outcome of thigh grafts has been reported only in retrospective studies. The outcomes of 409 grafts placed at a single institution during a 3.5-yr period were evaluated prospectively, including 63 thigh grafts (15% of the total). Information was recorded on surgical complications, dates of radiologic and surgical interventions, and date of graft failure. The technical failure rate was approximately twice as high for thigh grafts, as compared with upper extremity grafts (12.7 versus 5.8%; P = 0.046). Intervention-free survival was similar for thigh and upper extremity grafts (median, 3.9 versus 3.5 mo; P = 0.55). Thrombosis-free survival was also comparable for thigh and upper extremity grafts (median, 5.7 versus 5.5 mo; P = 0.94). Cumulative survival (time to permanent failure) was similar for thigh and upper extremity grafts (median, 14.8 versus 20.8 mo; P = 0.62). When technical failures were excluded, the median cumulative survival was 27.6 mo for thigh grafts and 22.5 mo for upper extremity grafts (P = 0.72). The frequency of angioplasty (0.28 versus 0.57 per year), thrombectomy (1.58 versus 0.94 per year), surgical revision (0.28 versus 0.18 per year), and total intervention rate (2.15 versus 1.70 per year) was similar between thigh and upper extremity grafts. Access loss as a result of infection tended to be higher for thigh grafts than for upper extremity grafts (11.1 versus 5.2%; P = 0.07). In conclusion, placement of thigh grafts should be considered a viable option among hemodialysis patients who have exhausted all options for a permanent vascular access in both upper extremities.     

Re-endothelialization of punctured ePTFE graft: an in vitro study under pulsed perfusion conditions.

BACKGROUND: When used as arteriovenous (AV) shunts for haemodialysis, small diameter expanded polytetrafluoroethylene (ePTFE) grafts have a high failure rate in vivo. Attempts to improve graft patency are various, and focus on either improvement of implantation techniques or graft tissue engineering. The tissue engineering approach attempts to reproduce in grafts the properties of pristine vasculature. As shown in previous experiments, it is possible to grow on ePTFE grafts under shear stress in vitro an autologous endothelial cell layer, which will withstand physiological stress under in vivo conditions of blood flow. The aim of this study was to investigate in an in vitro model the regenerative potency of a tissue-engineered prosthetic vascular graft after repeated cannulation with a haemodialysis cannula. METHODS: Pig endothelial cells were harvested from an external jugular vein. Following processing of the endothelial cells, seven ePTFE grafts were coated with an inner cell layer and were kept under pulsed perfusion. Each graft was then cannulated three times with a standard shunt needle. The endothelium was then left to regenerate for a maximum of 48 h. The grafts were stained with haematoxylin/eosin before histological study. RESULTS: All grafts were endothelialized over the puncture sites within 48 h. Histological analysis revealed a confluent endothelial cell lining at each puncture site. Cell morphology and cell pattern over puncture sites were not different from randomly picked locations over the graft lumen. CONCLUSION: Our results underline the potential of endothelial tissue engineering in vascular shunt surgery. Vascular bio-hybrids that have the properties of pristine vascular endothelium may be a key step forward in maintaining angio-access in patients who require haemodialysis.     

Transluminal iliac angioplasty with distal bypass surgery in patients with critical limb ischaemia

Transluminal balloon angioplasty of the iliac artery was combined with a distal bypass graft procedure in 25 patients with critical ischaemia of the lower limb. Eleven patients had angioplasty in the operating theatre before a vascular graft and the remaining 14 patients had percutaneous transluminal angioplasty performed in the X-ray department before bypass surgery. The distal bypass grafts were 20 femoropopliteal and five femorofemoral grafts. Two patients died in the immediate postoperative period. Follow-up of patients ranged from 2 to 26 months with a graft patency of 63% at 12 months and 50% at 24 months but successful limb salvage rate of 75% at 12 and 24 months. Six patients required major amputations for failure of limb salvage. Transluminal iliac angioplasty is a valuable adjunct to distal bypass surgery by improving arterial inflow without the requirement for major aorto iliac surgery.     

Implantation of the distal aorta: A technique for preservation of pelvic blood flow in aortofemoral reconstruction

We report our initial experience with a previously undescribed variation of aortofemoral bypass. This technique is an alternative to end-to-side aortic anastomosis for preservation of pelvic blood flow. It involves an end-to-end proximal aortic anastomosis with implantation of the distal aorta into the posterior wall of the bifurcation graft. This approach has been used selectively for nine patients. Seven patients operated on using this technique had bilateral external iliac artery disease preventing retrograde perfusion of the pelvis. We used this procedure in two other young patients to preserve large inferior mesenteric and distal aortic lumbar vessels proximal to common iliac artery occlusions. Mean follow-up has been 20 months. There have been no deaths and no major complications. This technique provides the hemodynamic benefit of a proximal end-to-end aortic anastomosis while maintaining patency of the distal aorta and its branches. Additional technical advantages may include better suture line protection from the duodenum and a decreased potential for graft limb kinking. These factors may ultimately result in superior long- term graft patency.Presented at the Annual Meeting of the Peripheral Vascular Surgery Society, New York, New York, June 17, 1989.     

Depopulated bovine ureteric xenograft for complex haemodialysis vascular access.

OBJECTIVES: To assess performance of a de-cellularised bovine ureter vascular graft for haemodialysis in patients for whom conventional access was not possible. METHODS: The Syner Graft Vascular Graft Model 100 (SGVG 100) is a bovine ureter modified by a tissue-engineering depopulation technology and uniquely it is not chemically cross-linked. SGVG 100 was implanted in patients with a failed fistula or vascular access grafts. Graft patency was the primary outcome; secondary outcomes included adverse events and associated treatments. RESULTS: 25 SGVG 100 were implanted in 23 patients; mean age was 59+/-14 years. Mean follow-up was 370 days. The mean time to occlusion (19 events) was 215+/-141 days with patency re-established in 14 of 18 surgical interventions. Thirty angioplasties were performed on 14 SGVG 100 for luminal/anastomotic stenosis. Two grafts demonstrated areas of dilation; however, both grafts continue to be usable at last reported follow-up (930 and 602 days) with no further changes in graft size. Primary patency, assisted primary patency, secondary patency, and freedom from infection were 29, 45, 81, and 95% at 1 year, respectively. CONCLUSIONS: This report demonstrates SGVG 100 is a stable vascular access conduit, providing a suitable graft alternative when autologous vein is not available.     

Clinical Use of Omniflow Vascular Graft as Arteriovenous Bridging Graft for Hemodialysis

Abstract: From April 1992 to November 1995, 109 bridging arteriovenous fistulas were performed in 89 patients for hemodialysis at National Taiwan University Hospital. These included 61 Omniflow vascular grafts (OVG) in 47 patients and 48 GoreTex polytetrafluoroethylene (PTFE) grafts in 42 patients. There were 36 male and 53 female patients, whose ages ranged from 24 to 84 years with a mean of 59 ± 2 years. The operation was performed under lidocaine local anesthesia with antibiotic prophylaxis. The anatomic configurations included 50 (45.9%) forearm loop grafts, 19 (17.4%) forearm straight grafts, and 40 (36.7%) thigh loop grafts. Hemodialysis via the bridging graft was started 2 weeks after the operation. The patients received hemodialysis 3 times a week or more when indicated. No patients suffered from limb loss. Pseudoaneurysm and graft infection requiring operation occurred 0.96% and 1.92% per patient year, respectively, in the OVG group, and pseudoaneurysm and graft infection both occurred 2.38% per patient in the PTFE group. In the OVG group, the thigh loop graft had better patency than the forearm straight graft. The forearm loop graft had a better patency rate than the forearm straight graft. In the OVG group, the 1 to 4 year patency rate was 77 ± 6%, 58 ± 8%, 48 ± 9%, and 34 ± 13%, respectively, whereas in the PTFE group, the 1 to 4 year patency rate was 69 ± 7%, 50 ± 9%, 43 ± 10%, and 26 ± 15%, respectively. Therefore, the Omniflow is a good alternative bridging graft for hemodialysis.     

Bovine and PTFE vascular graft results in hemodialysis patients

Purpose. There are many reports of patency periods, failure rates, thrombosis and infection attacks connected with vascular grafts. In this article, the results of polytetrafluoroethylene (PTFE) and Bovine grafts were compared in a forty-four month period. Methods. 61 vascular grafts (29 PTFE, 32 bovine) were placed in 49 patients. The grafts were compared in different ways, such as survival, complication rates and placement area using life survey analysis. Results. Mean survival time was 17 mo (SE +/- 2.8) for PTFE grafts and 11 mo (SE +/- 1.1) for bovine grafts. A failure rate of 34% due only to graft complications were found in PTFE and 25% in bovine grafts. All graft complications were seen in the first year. Comparison of the cumulative survival rates of the groups were found to be insignificant during the study period and the first year ( p>0.05). Regardless of the type, there was no signif-icant difference between the grafts placed in the forearm and the grafts in the thigh (p>0.05). Conclusions. There is no survival difference between PTFE and bovine grafts. First year of the grafts is important for developing complications.     

Factors involved in vascular calcification and atherosclerosis in maintenance haemodialysis patients.

BACKGROUND: Atherosclerosis and vascular calcifications are common causes of morbidity and mortality in maintenance haemodialysis patients. In addition to the well-known traditional risk factors, uraemia-specific factors appear to enhance dramatically the progression of the pathological processes involved. The aim of the present study was to evaluate the degree of atherosclerosis and vascular calcifications in chronic haemodialysis patients using non-invasive imaging methods, and to identify potentially involved factors. METHODS: The study included 73 patients (36 females, 37 males), aged 25-75 years, who were on haemodialysis treatment for 12-275 months (mean dialysis vintage 73.8 months). We assessed the following circulating parameters: calcium (Ca), phosphorus, 'intact' parathyroid hormone (iPTH), 25OH vitamin D, lipids, oxidized LDL (ox-LDL), Lp(a), homocysteine, leptin, IL-1-beta, IL-6, CRP, TGF-beta, TNF-alpha, (PDGF), advanced oxidation protein products (AOPP) and myeloperoxidase activity (MPO). Coronary artery calcification score (CACS) was assessed using multi-row spiral CT (MSCT). Intima-media thickness index of the common carotid artery (CCA-IMT) and presence of cervical artery atherosclerotic plaques were evaluated by ultrasonography. RESULTS: Coronary artery calcifications were observed in 79.5% of the patients, with CACS ranging from 0 to 4987. In univariate analysis, a positive correlation was observed between CACS and age, BMI, iPTH, CRP, IL-6 and CCA-IMT, whereas an inverse correlation existed with 25OH vitamin D, TGF-beta and PDGF. CCA-IMT ranged from 0.4 to 1.1 mm. It was positively correlated, in univariate analysis, with age, CACS, CRP and Il-6, and negatively with 25OH vitamin D, TGF-beta and PDGF. Only CACS remained as independent predictive factor of CCA-IMT in multivariate analysis. Atherosclerotic plaques were found in the carotid arteries of 53 patients (72%). The number of plaques was positively correlated with age, CACS, phosphorus, MPO, CRP and IL-6, and inversely with 25OH vitamin D in univariate analysis. In multivariate regression analysis, only age and CACS remained as independent variables. CONCLUSION: In addition to classic risk factors, the degree of atherosclerosis and vascular calcification in our dialysis patient population were associated with several factors that are frequently abnormal in advanced chronic renal failure, but except age, all of them were interdependent. Notably, as in the general population, CACS was an independent predictor of the degree of atherosclerosis in haemodialysis patients.     

Helical computed tomography angiography is the most efficient test to assess vascular calcifications in the iliac arterial sector in renal transplant candidates

The increased scope of renal transplant indications has lead to a larger number of recipients with vascular problems due to arterial calcifications in the iliac region. Compared to magnetic resonance and conventional arteriography, helical computed tomography angiography (HCTA) accurately depicts arterial diseases, including the location and extent of arterial calcification. The objective of this study was to assess the value of HCTA with maximum-intensity-projection (MIP) reconstruction to evaluate iliac arterial calcifications and stenosis among candidates for renal transplantation. MATERIAL AND METHODS: From December 1997 to March 2002, 114 HCTA scans with MIP reconstruction were performed in candidates for renal transplantation. Included patients fulfilled some of the following conditions: (a) older than 55 years, (b) diabetic, (c) second transplants, and (d) obvious vascular calcifications on plain abdominal x-ray. RESULTS: Among the 114 patients, 33 (29%) were excluded for transplantation due to universal calcification of the iliac arterial sector, and 81 (71%) were included on the waiting list due to the presence of calcium-free areas for the vascular anastomosis. Transplantation, which was attempted in 28 of the 81 patients, was successful in 25 using the area programmed after HCTA analysis. The transplants failed in three cases because no calcium-free area could be found upon surgical examination. CONCLUSION: HCTA with MIP reconstruction makes it possible to draw an exact map of the arterial calcifications of the iliac arterial sector, allowing better recipient selection and accurate planning for the vascular anastomosis and placement of the renal graft.     

Outcomes of thrombosed arteriovenous grafts: comparison of stents vs angioplasty

The usual radiologic approach to thrombosed grafts is a combination of thrombectomy and angioplasty of the underlying lesion. However, the primary (unassisted) graft patency after thrombectomy is quite poor. We evaluated whether graft patency following thrombectomy is improved by placement of a stent in the stenotic lesion. Using a prospective, computerized vascular access database, we identified 14 patients with thrombosed arteriovenous (A-V) grafts treated with a stent at the venous anastomosis (stent group). The outcomes of these grafts was compared to those observed in 34 sex, age-, and date-matched control patients whose thrombosed A-V grafts were angioplastied (control group). Both groups were comparable in age, sex, race, diabetic status, graft age, and number of previous graft interventions. The immediate technical success, as indicated by the post-procedure graft to systemic pressure ratio, was similar in the stent and control groups (0.33+/-0.16 vs 0.41+/-0.17, P=0.14). The primary graft patency (time from thrombectomy to next intervention) was significantly longer for the stent group (median survival, 85 vs 27 days, P=0.02). Assisted or secondary patency (time from thrombectomy to permanent graft failure) was also longer for the stent group (median survival, 1215 vs 46 days, P=0.049). In conclusion, treatment of thrombosed grafts with a stenosis at the venous anastomosis with a stent results in longer primary and secondary graft survival, as compared to treatment with angioplasty. Stent placement may be a useful treatment modality in a subset of patients with thrombosed A-V grafts and stenosis at the venous anastomosis.     

Results of kidney transplantation with simultaneous implantation of vascular graft

BACKGROUND: Arteriosclerosis and calcification of iliac arteries are common in patients on dialysis. This study sought to evaluate the outcome after kidney transplantation and simultaneous implantation of vascular grafts. PATIENTS AND METHODS: In a single center study we evaluated donor and recipient data among 443 kidney transplantations in adults performed between January 2002 and October 2006. In 11 recipients (2.5%) a vascular graft (Gore-Tex) was implanted due to severe arterioscleroses of the iliac vessels. RESULTS: Reconstruction of the lower limb blood supply was performed with an ileofemoral Gore-Tex-Bypass in 9 of 11 patients, with an aortofemoral bypass in 1 patient, and with a femoroiliac crossover bypass in 1 patient. Overall, 8 of 11 patients (73%) had an uneventful postoperative course. Six of 11 patients had primary graft function. CONCLUSIONS: This analysis demonstrated that vascular reconstruction during kidney transplantation has to be performed rarely but has a strong impact on further life and kidney function. In 8 of 11 patients, kidney function at 6 months was good. Severe arteriosclerosis is usually not a contraindication for kidney transplantation. However, training in vascular surgery seems to be important to achieve satisfying results. In this series, simultaneous implantation of vascular prosthetic grafts was safe since there were no infectious complications of the graft itself.     

Clinical experiences with 43 cases of laparoscopic reconstruction in aortoiliac occlusive diseases: analysis of morbidity, effectiveness and treatment results

Between October 1995 and April 2000 we performed 30 aortic laparoscopic reconstructions and 13 procedures on the iliac vessels. Severe aortic calcifications, poor cardiac and pulmonary status, and extensive intraabdominal adhesions were considered as contraindications for the laparoscopic procedure. Operative time, conversion rate, surgical and cardiopulmonary complications were recorded for an intention- to treat-analysis. Clinical criteria and Duplex ultrasound scans were used to document the patency of the grafts. The duration of analgetic therapy, nursing care, and hospital stay characterized the postoperative recovery. Mean surgical time was 302 minutes (min) in the aortic group (Ao) and 251 min in the iliac group (Ia). Seven conversions (5 in the aortic and 2 in the iliac group) occurred for clamping problems (n = 3), aortic lesion (n = 1), iliac vein lesion (n = 1), time consuming dissection (n = 1), and suturing failure (n = 1). Cardiac morbidity rate was 6.6% (Ao) and 7.7% (Ia). Two patients suffered pulmonary complications after aortic surgery (6.6%). Mean duration of analgetic therapy was 2.4 d (Ao) and 2.5 d (Ia). Nursing care was necessary for 4.4 d (Ao) and 3.1 d (Ia). At discharge the reconstructions were patent and ischemia symptoms subsided in all cases. Mean hospital stay was 9.1 d (Ao) and 6.7 d (Ia). At follow-up after a mean interval of 5.2 months (Ao) and 8.3 mo (Ia) patency was documented in all cases. Disease progression in the adjacent native vessels (n = 3) and beyond the graft (n = 1) was revealed by ultrasound scan, requiring a further vascular procedure. In our laparoscopic experience cardiac and pulmonary morbidity proved similar to traditional vascular surgery. The advantage of the minimally invasive approach seemed to be a more comfortable recovery. However, operative time and conversion rate emphasize the technical challenge of the procedure, which should be performed only in highly selected cases.     

Axillo-iliac conduit for haemodialysis vascular access.

OBJECTIVES: To describe a series of venous surgical procedures performed to maintain vascular access. METHODS: We report eight patients with end-stage renal failure (ESRF) who had complex renal access problems. Three patients had central venous occlusion and underwent veno-venous axillo-iliac bypass. In five further patients with a symptomatic central venous obstruction we performed axillo-iliac arterio-venous grafting (AVGs) in order to achieve haemodialysis access. All patients were assessed pre-operatively with duplex ultrasound and venogram of upper and lower limbs. The axillary artery or vein, and iliac vein were approached via infraclavicular and extra-peritoneal groin incisions, respectively. Non-externally-supported polytetrafluoroethylene (PTFE) was used as a conduit in all patients and anti-coagulation regimen were commenced post-operatively. RESULTS: Following venous diversion surgery, there was a dramatic improvement in the facial and limb swelling experienced by the patients. There was no significant peri-operative morbidity. The veno-venous graft is still patent at 14 months in patient one, at 10 months in patient two, and 5 months in patient three. In the second group, who had arterio-venous grafts, the mean follow-up was 13.2 (7-20) months with a secondary patency rate of 80% at 6 months. Four patients had patent, usable grafts at 12 months. In two cases, graft occlusion was treated with successful thrombectomy. CONCLUSION: Axillary-iliac veno-venous diversion can overcome the symptoms and complications of superior vena cava and innominate vein obstruction. Although, axillo-iliac arterio-venous graft fistulae formation was previously described it has not been widely used. We have found the procedure to have low morbidity and advocate its use in these complex cases.     

X线平片在诊断血液透析患者血管钙化中的应用

目的 评价X线平片检测维持性血液透析（MHD）患者动脉钙化的敏感性和特异性。 方法 54例MHD患者行腹部-股骨上1/3多层螺旋CT（MSCT）平扫及侧位腹平片、骨盆片X线检测。以腰椎（L）2～3间隙为界将腹主动脉分为上段、下段。MSCT结果据钙化严重程度分为0~5级。两位放射科医师分别盲法阅片诊断。以MSCT结果为金标准,X线平片结果作为诊断性指标,评价X线平片诊断腹主动脉和髂、股动脉钙化的敏感性和特异性。 结果 MSCT结果显示,腹主动脉钙化发生率为86.1%,髂、股动脉钙化发生率为74.5%,二者差异有统计学意义（χ2 = 5.695,P = 0.017）;腹主动脉2级以上钙化的发生率为60.2%,髂、股动脉为42.6%,腹主动脉钙化的严重程度显著高于髂、股动脉（χ2 = 8.922,P = 0.003）。X线平片结果表明,腹主动脉钙化发生率为51.9%,髂、股动脉钙化发生率为18.5%。X线平片诊断腹主动脉和髂、股动脉钙化的特异性均为100%,敏感性随MSCT动脉钙化程度的加重而增高。据MSCT钙化评分的不同,其诊断腹主动脉和髂、股动脉钙化的敏感性分别如下：≥1级：60.2%和24.8%;≥2级：76.9%和43.5%;≥3级：100%和74.4%。 结论 X线平片诊断中、重度动脉钙化敏感性高,诊断腹主动脉钙化的敏感度高于髂、股动脉,可用于MHD患者中、重度动脉钙化的检测。