Preoperative evaluation of potential living related kidney donors with high-spatial-resolution magnetic resonance (MR) angiography at 3 Tesla: comparison with intraoperative findings

PURPOSE: The purpose of this prospective study was to determine the feasibility and accuracy of high-spatial-resolution MR imaging at 3 Tesla (T) in the preoperative evaluation of potential living related kidney donors. MATERIALS AND METHODS: Eighteen potential donors (8 men, 10 women; mean age, 50.1 +/- 14.2 years) for renal transplantation were evaluated with 3 T MR imaging. A high-spatial-resolution 3-dimensional (3D) gradient-echo MR angiography (repetition time/echo time, 3.0/1.14 ms; flip, 19-23 degrees; matrix, 512; slice thickness, 1.0 mm) using parallel acquisition technique (GRAPPA) with an acceleration factor of 3 was performed on a whole body scanner. Images were evaluated in a prospective and blinded fashion by 2 MR radiologists. The number of renal arteries, presence of early branches (defined as a branch arising within 2 cm of the main renal ostium), and renal artery stenosis were analyzed. The renal parenchyma, collecting system and ureters, were evaluated on the MR urograms. Interpretation of MR images were compared with surgical findings. RESULTS: Based on MR angiography data sets, a total of 36 main and 9 accessory renal arteries was found. There were 5 renal arteries presenting an early branching (相似文献   

Pre-kidney-transplant evaluation of donors and recipients

The pretransplant imaging evaluation of recipients is mainly achieved with CT and has two objectives: detection of iliac artery calcifications that may have an impact on the site of the transplant and the type of arterial anastomosis; detection of a primary malignancy that would be a contraindication to transplantation. The pretransplant imaging evaluation of living donors relies on noninvasive techniques. CT angiography and MR angiography both allow the simultaneous evaluation of arteries, excretory tract and renal parenchyma. The goal is to achieve anatomical and functional renal evaluation in order to select the best donor and plan the surgical procedure.     

Donor renal angiography: its influence on the decision to use the right or left kidney

The left kidney from a living, related donor is preferred for kidney transplantation because it has a longer renal vein and thus is easier to implant in the recipient. However, anatomic variations in the renal arteries occasionally dictate the choice of the right kidney instead. To determine the influence of angiographic findings on the decision to use the right or the left kidney for transplantation, we assessed the role of preoperative angiography in the evaluation of living, related kidney donors. The records of 81 potential renal donors who underwent arteriography were reviewed. Three patients did not undergo donor nephrectomy, for reasons unrelated to the results of arteriography. Of the remaining 78 patients, two-thirds (52) underwent left nephrectomy as planned. A right nephrectomy was performed in the other 26 donors. In 19 of these 26 patients (24% of the 78 who underwent nephrectomy), the right kidney was chosen because of anatomic variations in the renal arteries seen on arteriography. Right donor nephrectomy was performed in the remaining seven of the 26 patients because of venous or collecting-system variants in the left kidney in three and because of better anatomic compatibility with the recipient in the other four. We conclude that donor angiography will dictate the choice of kidney in approximately one-fourth of prospective renal donors.     

CT Angiography for Living Kidney Donors: Accuracy, Cause of Misinterpretation and Prevalence of Variation

OBJECTIVE: To determine the accuracy of the use of multi-detector row CT (MDCT) to predict vascular anatomy in living kidney donors and to reveal the prevalence of vascular variations in a Korean population. MATERIALS AND METHODS: A total of 153 living kidney donors that had undergone preoperative CT and nephrectomy, either with open or laparoscopic surgery, were selected retrospectively. The initial CT results were compared with the surgical findings and repeated review sessions of CT scans were performed to determine the causes of mismatches in discordant cases. RESULTS: The accuracy of CT angiography was 95% to predict the number of renal vessels. Four arteries and two veins were missed during the initial CT interpretation due to perception errors (for two arteries and two veins) and technical limitations (two arteries). The prevalence of multiple renal arteries and veins, early branching of a renal artery and late confluence of a renal vein were 31%, 5%, 12%, 17%, respectively. The circumaortic renal vein and the bilateral inferior vena cava were found in two cases each (1.3%). One case (0.7%) each of a retroaortic renal vein and a supradiaphragmatic originated renal artery were found. CONCLUSION: MDCT provides a reliable method to evaluate the vascular anatomy and variations of living kidney donors.     

64层CT肾血管成像在肾移植供体评价中的临床应用价值

目的:评价64层螺旋CT肾血管成像技术在肾移植供体评价中的临床应用价值。方法:对40例亲属供肾者行64层螺旋CT肾血管成像,应用容积再现(VR)、最大密度投影(MIP)、多平面重组(MPR)等技术进行肾血管重建,评价供肾血管情况,将影像学表现与术中所见进行对照。结果:40例供肾者1次屏气完成扫描,均获得满意的轴面图像,应用VR、MIP、MPR等后处理技术重建肾血管,可清晰显示肾动脉主干及其2～4级分支。9例单侧肾由副肾动脉供血,其中8例单侧肾见单支副肾动脉,1例双侧肾各见1支副肾动脉;9例存在肾动脉分支过早,其中1例双肾动脉均为肾动脉分支过早,共10支血管距离肾动脉开口在1.5cm以内;2例显示肾静脉解剖变异。CT血管成像对供肾动静脉主干、副肾动脉、肾动脉分支过早、肾静脉主干变异的显示与术中所见一致。结论:64层螺旋CT肾血管成像是肾移植术前评价活体供肾血管的一种无创、安全、经济、有效的检查方法。     

Preoperative evaluation of living renal donors: comparison of CT angiography and MR angiography

PURPOSE: To compare computed tomographic (CT) angiography and magnetic resonance (MR) angiography for preoperative evaluation of living renal donors. MATERIALS AND METHODS: Thirty-five living renal donors underwent preoperative contrast material-enhanced CT angiography and gadolinium-enhanced MR angiography. Each study was interpreted by two independent radiologists blinded to all other studies and to interpretations provided by other reviewers. Eighteen kidneys had surgical correlation. RESULTS: CT demonstrated 33 supernumerary arteries in 19 patients, bilateral solitary arteries in 16 patients, and 18 proximal arterial branches in 16 patients. MR demonstrated 26 supernumerary arteries in 15 patients, bilateral solitary renal arteries in 20 patients, and 21 proximal arterial branches in 16 patients. Interobserver agreements for MR (kappa = 0. 74) and CT (kappa = 0.73) were similar to the agreement between MR and CT (kappa = 0.74). Among the kidneys chosen for nephrectomy, one small accessory artery and one proximal arterial branch were missed with CT and MR. Two of the accessory arteries suggested at CT were not found at nephrectomy. By averaging data for both modalities, supernumerary arteries were present in 49% of kidney donors and were bilateral in approximately 17%. Proximal arterial branches were present in 46% of kidney donors. CONCLUSION: Preoperative CT and MR angiography of the renal arteries in renal donors demonstrate substantial agreement. Interobserver disagreement in the interpretation of CT and MR angiograms is related to 1-2-mm-diameter vessels.     

Limitations of digital subtraction angiography in evaluating potential renal donors

Six potential renal donors were evaluated by both conventional and digital subtraction angiography to determine the number of renal arteries to each kidney. The digital examination missed an accessory renal artery in one of six patients for an error rate of 17%.     

Arterial digital angiography in the evaluation of potential renal donors

Twenty-two potential renal donors were examined by both arterial digital and conventional aortography. The digital studies accurately identified all of the renal arteries. Digital subtraction angiography may be a suitable alternative to conventional aortographic evaluation of the renal arterial supply of potential renal donors.     

Evaluation of renal arteries in living renal donors: comparison between MDCT angiography and gadolinium-enhanced 3D MR angiography

Purpose The purpose of this study was to clarify and compare the accuracy of contrast-enhanced computed tomography (CT) angiography using multidetector-row helical CT (MDCT angiography) and gadolinium-enhanced MR angiography using three-dimensional Fourier transformation gradient-echo sequence (3D MR angiography) for preoperative evaluation of renal arteries in living renal donors. Materials and methods A total of 42 living renal donor candidates underwent both MDCT angiography and 3D MR angiography before digital subtraction angiography (DSA). Each MDCT angiogram and 3D MR angiogram was prospectively interpreted, and the findings were compared with the DSA results. Results MDCT angiography identified all of the 12 supernumerary arteries detected by DSA, whereas 3D MR angiography identified only 8. MDCT angiography identified all of the 19 proximal arterial branches detected by DSA, whereas 3D MR angiography identified only 16. Conclusion A more accurate depiction of renal arteries in living renal donors can be achieved with MDCT angiography than with 3D MR angiography.     

Diagnostic use of angiotensin converting enzyme (ACE)-inhibited renal scintigraphy in the identification of selective renal artery stenosis in the presence of multiple renal arteries: a case report

In patients with renovascular hypertension, it is unknown whether the angiotensin converting enzyme-(ACE) inhibited renal scan will identify stenosis of a segmental branch of a single renal artery or of an accessory artery where multiple renal arteries are present. Since multiple renal arteries may be present in approximately 25% of all individuals, it will be important to establish whether the ACE-inhibited renal scan is useful in this population. We report a case of stenosis involving a renal artery in a patient with multiple renal arteries, successfully identified by ACE-inhibited renal scintigraphy.     

动态增强MR血管成像对活体肾移植供体术前的评估

目的 探讨动态增强MRA对活体肾移植供体血管解剖的显示情况.方法 35名肾移植供体,术前行MRA检查.首先经静脉注入1 ml对比剂Gd-DTPA,测出循环至肾动脉时间.然后行冠状面3D T1加权快速扰相小角度梯度回波(3D FLASH)序列扫描.自动脉期开始连续扫描4期,每期间隔10 s,获得肾动脉、肾静脉、集合系统等各期图像.2名放射科医师观察原始图像及MIP重组后图像,观察肾动脉、肾静脉及其分支的显示情况,确定血管的走形及有无变异.并把MRA图像质量确定为5级,与32名手术结果进行比较.结果 MRA对于肾动脉、肾静脉系统的显示质量均较好.35名供者70个肾脏中发现5支左肾副动脉,9支右副肾动脉.3支左肾动脉过早分支,6只右肾动脉过早分支,其中1支右侧双肾静脉,2例左侧精索静脉粗大.1例右肾副上极动脉MRA术前未发现.结论 动态增强MRA安全无创,对肾动脉、肾静脉显示清楚,诊断变异准确度高,是术前肾移植供体血管评价较好的影像检查手段.     

动态增强MR血管成像对活体肾移植供体术前的评估

目的 探讨动态增强MRA对活体肾移植供体血管解剖的显示情况.方法 35名肾移植供体,术前行MRA检查.首先经静脉注入1 ml对比剂Gd-DTPA,测出循环至肾动脉时间.然后行冠状面3D T1加权快速扰相小角度梯度回波(3D FLASH)序列扫描.自动脉期开始连续扫描4期,每期间隔10 s,获得肾动脉、肾静脉、集合系统等各期图像.2名放射科医师观察原始图像及MIP重组后图像,观察肾动脉、肾静脉及其分支的显示情况,确定血管的走形及有无变异.并把MRA图像质量确定为5级,与32名手术结果进行比较.结果 MRA对于肾动脉、肾静脉系统的显示质量均较好.35名供者70个肾脏中发现5支左肾副动脉,9支右副肾动脉.3支左肾动脉过早分支,6只右肾动脉过早分支,其中1支右侧双肾静脉,2例左侧精索静脉粗大.1例右肾副上极动脉MRA术前未发现.结论 动态增强MRA安全无创,对肾动脉、肾静脉显示清楚,诊断变异准确度高,是术前肾移植供体血管评价较好的影像检查手段.     

动态增强MR血管成像对活体肾移植供体术前的评估

目的 探讨动态增强MRA对活体肾移植供体血管解剖的显示情况.方法 35名肾移植供体,术前行MRA检查.首先经静脉注入1 ml对比剂Gd-DTPA,测出循环至肾动脉时间.然后行冠状面3D T1加权快速扰相小角度梯度回波(3D FLASH)序列扫描.自动脉期开始连续扫描4期,每期间隔10 s,获得肾动脉、肾静脉、集合系统等各期图像.2名放射科医师观察原始图像及MIP重组后图像,观察肾动脉、肾静脉及其分支的显示情况,确定血管的走形及有无变异.并把MRA图像质量确定为5级,与32名手术结果进行比较.结果 MRA对于肾动脉、肾静脉系统的显示质量均较好.35名供者70个肾脏中发现5支左肾副动脉,9支右副肾动脉.3支左肾动脉过早分支,6只右肾动脉过早分支,其中1支右侧双肾静脉,2例左侧精索静脉粗大.1例右肾副上极动脉MRA术前未发现.结论 动态增强MRA安全无创,对肾动脉、肾静脉显示清楚,诊断变异准确度高,是术前肾移植供体血管评价较好的影像检查手段.     

Noninvasive imaging of living related kidney donors: evaluation with CT angiography and gadolinium-enhanced MR angiography.

OBJECTIVE: This study was performed to determine whether noninvasive imaging with CT angiography and MR angiography in the preoperative investigation of living, related kidney donors provides sufficient information for the surgeon. MATERIALS AND METHODS: Eighty consecutive potential living kidney donors were investigated. Fifty patients underwent CT angiography and 30 underwent MR angiography before donor nephrectomy. CT was performed using 3-mm collimation with a pitch of 1.6 after the injection of 150 mL of nonionic contrast medium. The axial data, multiplanar reconstructions, and maximum intensity projections were reviewed. MR angiography was performed on a 1-T magnet using a contrast-enhanced three-dimensional gradient echo technique. Maximum intensity projections and axial reformations were reviewed. Imaging findings were compared with the surgical results in 54 patients. RESULTS: CT angiography and MR angiography were 100% sensitive in identifying the main renal arteries and renal veins. CT angiography visualized 37 of the 40 arteries identified at surgery, for a detection rate of 93%. MR angiography visualized 18 of the 20 arteries identified at surgery, a detection rate of 90%. CONCLUSION: CT angiography and MR angiography are suitable for the noninvasive investigation of living kidney donors and provide all the information required by the surgeon. Both methods may miss small accessory renal arteries. MR angiography does not use potentially toxic contrast material or radiation and is the preferred investigation, with CT angiography reserved for patients unable to tolerate MR imaging.     

64层CT VR技术在活体肾移植供体血管评价中的应用

目的 探讨MSCT血管造影容积再现(VR)技术在活体肾供体术前综合评价中的应用价值. 资料与方法 对55例供体术前的肾脏血管结构的MSCT VR表现进行分析. 结果 19例可见25支副肾动脉、2例可见肾动脉过早分支、2例可见单侧双肾静脉、1例可见肠系膜上动脉压迫肾静脉.合乎临床要求的供肾46例. 结论 MSCT VR可较好地显示供体术前的肾脏血管结构.     

Magnetic resonance angiography in potential live renal donors: a joint radiological and surgical evaluation

AIM: To assess the impact of a joint surgical and radiological audit on the accuracy of contrast-enhanced magnetic resonance angiography (MRA) reports in the evaluation of potential renal donors. MATERIALS AND METHODS: We analysed the records of live renal donors who underwent gadolinium-enhanced MRA as part of the pre-operative evaluation to assess renal vasculature between August 1999 and July 2002 when feedback from surgical findings to radiology had been available. In cases of discrepancy between MRA reports and surgical findings, studies were retrieved from the magnetic resonance imaging (MRI) workstation and subjected to detailed joint clinical and radiological review. Scan quality was assessed and sources of discrepancy were identified. RESULTS: There were 45 donors, 23 men and 22 women with a mean age of 41 years. Reported MRA findings were fully confirmed at surgery in 38 of 45 cases. These images were not analysed further. In seven donors the findings at surgery were discrepant with the radiological reports: there were four cases of "missed" early branches and three cases of "missed" accessory arteries. In the first year of the audit there were four discrepant cases out of 18 (22%), all of which were radiological reporting errors. The number of discrepant cases in the second year was two out of 19 cases (11%). Neither of these was a radiological reporting error. There was one "missed" early renal artery branch in the third year of audit, which was identified on MRA review. CONCLUSION: The study highlights the importance of detecting and clearly reporting not only accessory renal arteries, but also early renal arterial branches in the pre-operative evaluation of renal donors. The accuracy of pre-operative MRA in potential renal donors is high, but radiological reporting of MRA examinations is improved through careful clinical feedback, audit and interdisciplinary co-operation.     

Assessment of 100 live potential renal donors for laparoscopic nephrectomy with multi-detector row helical CT

PURPOSE: To retrospectively review the authors' experience with multi-detector row helical computed tomography (CT) in assessing 100 consecutive live potential renal donors. MATERIALS AND METHODS: Hospital ethical committee approval was obtained; informed patient consent was not required. One hundred potential renal donors underwent multi-detector row CT assessment. Nonenhanced, arterial phase, and nephrographic phase examinations were performed. Delayed topograms were acquired to visualize the collecting system anatomy. A vascular radiologist prospectively interpreted the multi-detector row CT images. A second vascular radiologist, blinded to the initial results, retrospectively reviewed the images. Eighty candidates subsequently underwent donor nephrectomy, including 70 laparoscopic donor nephrectomies (LDNs) and 10 open donor nephrectomies (ODNs). Surgical findings served as the reference standard for 80 kidneys. The imaging findings in all 100 candidates (200 kidneys) were reviewed, although these findings were considered observational data only because there was no reference standard for 120 kidneys. RESULTS: Multi-detector row CT findings predicted uncomplicated LDN in 67 of 70 patients. Small upper-pole capsular arteries arising from the distal main renal artery in two patients were not described in the multi-detector row CT report: In one patient, the arising vessels resulted in conversion to ODN because of bleeding; in the other patient, arterial reconstruction was performed. In another patient, conversion to ODN was necessary because of ongoing bleeding from an avulsed large lumbar venous tributary to the left renal vein. Observational data revealed that multiple renal arteries--most of which were accessory renal arteries--were seen in 52 (26%) kidneys. Early branching of the main renal artery was seen in 24 (12%) kidneys, and main renal arterial abnormalities were identified in six (3%). Capsular arteries were detected in 10 (5%) kidneys. Major variations in the anatomy of the main renal veins--including multiple right renal veins, a retroaortic left renal vein, and a circumaortic left renal vein--were seen in 28 (14%) kidneys. Large (>5 mm in diameter) systemic tributaries to the left renal vein were seen in 25 (25%) kidneys. There was no significant interobserver disagreement between the vascular radiologists. CONCLUSION: Multi-detector row CT findings can predict successful LDN in live potential renal donors.     

Hepatic arteries in potential donors for living related liver transplantation: evaluation with multi-detector row CT angiography

PURPOSE: To assess the accuracy of multi-detector row computed tomographic (CT) angiography in the evaluation of hepatic arterial anatomy in living related liver transplantation (LRLT) donors. MATERIALS AND METHODS: During a 10-month period, 62 potential LRLT donors were evaluated with CT and conventional angiography. Multi-detector row CT was performed after intravenous injection of 150 mL of contrast material at 3 mL/sec. CT angiograms of the hepatic arteries were generated by a radiologist who used volume rendering and maximum intensity projection techniques without knowledge of results of conventional angiography. Two reviewers reviewed CT and conventional angiograms retrospectively in consensus. The results of the two examinations were then compared. RESULTS: CT examinations were technically adequate in 56 (90%) donors. Respiratory motion artifact compromised detailed hepatic artery analysis in six donors (10%). Second-order branches of right hepatic arteries were visualized in 58 donors (94%), and second-order branches of left hepatic arteries were visualized in 51 (82%). A total of 27 hepatic arterial anatomic variations were detected in 22 donors at conventional angiography. CT angiography accurately depicted 25 (93%) anatomic variations in 20 donors (91%). CT angiography did not depict an accessory right hepatic artery in two donors. The number and origins of dominant arteries supplying segment IV were accurately identified at CT angiography in 51 donors (82%). Hepatic arterial anatomy depicted at CT angiography was identical to that at conventional angiography in 50 donors (81%). CONCLUSION: Multi-detector row CT angiography is useful but limited in its ability to depict the dominant artery supplying segment IV and small accessory hepatic arteries.     

肾移植患者微小病毒B19感染的实验研究

目的：研究肾移植术后微小病毒B19感染的情况。方法：采用间接ELISA的方法检测肾移植术后患者血清标本中抗微小病毒－B19（HPV－B19）IgM和IgG抗体的浓度,并与肾移植前及健康献血员进行比较。结果：肾移植后患者血清标本中HPV－B19IgM抗体的浓度和阳性率明显高于肾移植前和健康对照,而HPV－B19IgG抗体无明显改变。结论：肾移植术后,机体免疫力下降,HPV－B19感染的机率上升,可能引起以贫血为主的多系统多器官的功能障碍,影响肾移植的效果。     

螺旋CT肾动脉成像与数字减影血管造影的对比分析

目的:客观评价螺旋CT肾动脉成像的临床应用价值.材料和方法:从本院螺旋CT肾动脉成像(CTRA)资料中选取31例曾做过DSA肾动脉造影(含动脉成形和支架放置术)者,CTRA和DSA图像分别先由两位医师独立观察.分析内容包括解剖变异、有无狭窄及进行狭窄程度分级.最后将结果进行对比分析.结果:CTRA发现狭窄血管33支,其中31支经DSA证实(2支假阳性).符合率为94%.清楚显示5支副肾动脉(经DSA证实).结论:CTRA是肾性高血压筛选的可靠方法并可取代DSA作为首选检查方法.