Multidetector CT angiography in live donor renal transplantation: experience from 156 consecutive cases at a single centre

Assessment of renal vascular anatomy on multi-detector computed tomography in living renal donors

BACKGROUND

Prospective renal donors are a select population of healthy individuals who have been thoroughly screened for significant comorbidities before they undergo multi-detector computed tomography angiography and urography (MDCT).

PURPOSE

The aim of this study is to describe the anatomy of potential living renal donor subjects using MDCT over a 2-year period. The primary objective is to identify the renal arterial anatomy variations, with a secondary objective of identifying venous and collecting system/ureteric variations.

MATERIALS AND METHODS

A prospective study was performed of prospective living kidney transplant donors at a national kidney transplant centre. Study inclusion criteria were all potential kidney donors who underwent MDCT during the living-donor assessment process over a 2-year period.

RESULTS

Our cohort included 160 potential living donors who had MDCT; mean age was 45.6 years (range, 21-71). Two renal arteries were identified on the left in 40 subjects (25%) and on the right in 42 subjects (26.3%). A total of 3 or more renal arteries were identified on the left in 7 subjects (4.4%) and on the right in 7 subjects (4.4%). On the left, the distances between multiple arteries ranged from 1 mm to 43 mm, and on the right, they were 1 mm to 84 mm.

CONCLUSIONS

Conventionally described anatomy was only seen on the left side in 70.6% and 69.4% on the right side of subjects. Single renal arteries are seen in 54.4% showing that conventional anatomy has a relatively low incidence.

Impact of grafting using thin upper pole artery ligation on living-donor adult kidney transplantation: The STROBE study

This study aimed to investigate the impact of grafting using thin upper pole artery ligation for living-donor adult kidney transplantation. Few reports have examined the safety of thin upper pole artery ligation.Between January 2008 and May 2015, 613 consecutive living-donor adult kidney transplantations were performed. We excluded 21 recipients who experienced graft loss due to factors that were unrelated to surgical complications and 3 recipients with grafts treated with arterial reconstruction and thin upper pole artery ligation for 3 arteries. We included 439 kidney grafts with single arteries (Single Artery Group), 123 with reconstructed arteries (Arterial Reconstruction Group) and 27 with ligated thin upper pole arteries (Arterial Ligation Group) in this retrospective cohort study. To evaluate the safety of thin upper pole artery ligation, we compared the Arterial Ligation Group with the Single Artery and Arterial Reconstruction groups. We evaluated the characteristics of the enrolled donors, recipients, and their grafts. Thereafter, we investigated recipients' perioperative and postoperative estimated glomerular filtration rate (eGFR) and complication rates.Significant differences among the 3 groups were identified for donor sex and endoscopic nephrectomy rates. Recipient eGFR and the complication rates were adjusted according to these factors. The perioperative and postoperative eGFR of recipients did not differ significantly in the Arterial Reconstruction and Single Artery groups with low complication rates.Thin upper pole artery ligation is a safe procedure for living-donor adult kidney transplantation and may prevent unnecessary arterial reconstruction and associated complications.

Evaluation of Renal Arteries of 286 Living Donors by Multidetector Computed Tomography Angiography: A Single-Center Study

OBJECTIVES

In living renal donors, digital subtraction angiography and intravenous pyelogram techniques developing traditional evaluation before transplant have started to give place to more modern and less-invasive methods such as multidetector computerized tomography angiography, and magnetic resonance angiography via the developments in the imaging technology. We aimed to evaluate the renal arteries of living-renal donors by multidetector computerized tomography angiography and to compare the findings with the surgical results.

MATERIALS AND METHODS

In our renal transplant center, 286 living-donor candidates to whom multi-detector computerized tomography angiography was applied, were evaluated retrospectively and the findings were compared with the surgical operation notes.

RESULTS

In 180 of 286 living donor candidates to whom computerized tomography angiography was applied, bilateral single renal artery was deter-mined. In 79 renal donor candidates, unilateral multiple renal artery; and in 27 renal donor candidates, bilateral multiple renal artery were found. In 58 renal donor candidates, at least 1 polar artery was specified; in 32 renal donor candidates, a unilateral single renal artery; in 10 renal donor candidates, a bilateral double renal artery was determined. When computerized tomography angiography and operative notes were compared, we observed that the findings in 280 donor candidates were the same. In 6 renal donor candidates, differences in the findings were present. Our accuracy rate was 97% and according to the operative notes, our sensitivity and specificity ratios in determining multiple renal arteries were calculated as 98% and 95%.

CONCLUSIONS

Multidetector computerized tomography angiography can be used rapidly and efficiently in living-donor renal candidates with high specificity and sensitivity ratios.

Diagnostic accuracy of 64-MDCT angiography in the preoperative evaluation of renal vessels and compared with laparotomy findings in living donor kidney

INTRODUCTION

Multidetector-row computed tomography (MDCT) angiography is a reliable technique in preoperative renal anatomy evaluation in live renal donors.

OBJECTIVES

To investigate the accuracy of early arterial phase findings and compares them with intraoperative findings.

METHODS

In this prospective study, 100 potential live donors undergoing preoperative MDCT and nephrectomy during 2010-2013 were included. The examination was performed with a 64-detector scanner including early arterial and venous phase. MDCT angiography started by bolus tracking and venous phase was acquired 9 s after arterial phase. Anatomical findings and vein and artery attenuation values were recorded and arterial phase findings were compared with intraoperative findings.

RESULTS

All anatomical findings reported by MDCT in early arterial phase were confirmed by intraoperative findings with sensitivity of 100%. Right renal vein was supernumerary in 17 cases and left renal vein was circumaortic in 3 and retroaortic in 5 cases. Renal arteries had early branching in 13, two arteries in 12 and accessory in 8 cases. Vein and artery attenuation values had significant difference between early arterial and venous phase (p < 0.001).

CONCLUSION

Early arterial phase has similar results to venous phase in preoperative evaluation and intraoperative findings and could be used alone to reduce radiation dose.

Role of multidetector computed tomography for evaluation of living kidney donors

Background

Kidney transplantation from living donors has been increased recently. Preoperative evaluation of living donor is important to select the appropriate kidney for transplantation and to decrease donor surgical complications.

Objectives

The aim of this study was to compare the accuracy of the use of multidetector computed tomography (MDCT) to evaluate vascular anatomy in living kidney donors with traditional angiography.

Patients and Methods

A total number of 60 living kidney donors who underwent open surgical approach for transplantation were selected: Kidney anatomy of donors evaluated by CT angiography (group 1) or traditional angiographic examination (group 2). Renal vessels anatomy was compared with surgical findings in both groups.

Results

The accuracy for detecting number of main renal arteries were not different in both groups which were 96.7% in CT angiography group and 90% in traditional angiography group (P = 0.15). The accuracy for detection of main renal veins were 100% in group 1 and 96.7% in group 2 (P = 0.31).

Conclusions

MDCT has the same accuracy as traditional angiography to detect renal abnormalities in living kidney donors.

Role of MDCT angiography in selection and presurgical planning of potential renal donors

OBJECTIVE

The purpose of this study was to determine the prevalence and types of renal and extrarenal abnormalities that preclude renal donation or lead to alteration of the surgical approach on the basis of abdominal CT angiography (CTA) in a large group of potential renal donors.

MATERIALS AND METHODS

In this retrospective study, 654 potential renal donors undergoing dual-phase CTA were identified from January 2005 to January 2009. The CT reports were systemically reviewed by two radiologists to determine the presence of renal and extrarenal abnormalities. The operative notes of the renal donors were reviewed by one radiologist to determine whether the presence of renal pathology had affected the surgical approach. In the candidates who did not proceed to kidney donation, the reasons that precluded kidney donation were abstracted from the transplant database.

RESULTS

Four hundred seventeen potential donors (269 men and 385 women; mean age, 44.0 years; age range, 17-79 years) proceeded to renal donation and 237 did not. The most common renal abnormalities were cysts (34%) and renal stones (4.4%). Renal artery disease was identified in 3.4% of potential donors, including renal artery stenosis, possible fibromuscular dysplasia, and renal artery aneurysm. Suspicious renal masses were incidentally found in 0.5% of potential donors. The most common extrarenal pathology was an incidental adrenal nodule (2.6%). Other significant extrarenal pathology identified included gallbladder mass (0.2%), Crohn disease (0.2%), ovarian mass (0.2%), and possible sarcoidosis (0.2%). Although renal and extrarenal abnormalities were present in 41% of potential renal donors, abnormalities seen on CT only contributed to exclusion of 27 potential donors (4.1%). The most common reason for exclusion was the presence of renal stones or scarring (1.8%). Significant CT findings also contributed to the selection of the right kidney in 29 donors, most commonly due to presence of ipsilateral vascular disease or complex left vascular anatomy.

CONCLUSION

Renal parenchymal and vascular abnormalities are common in asymptomatic potential kidney donors. Although most of these represent incidental CT findings, abnormalities can exclude potential renal donors and alter the surgical approach in a small minority of cases.

Is there a role for free breathing non-contrast steady-state free precession renal MRA imaging for assessing live donors? A preliminary study

OBJECTIVE

Accurate pre-operative evaluation of renal vascular anatomy is essential for successful renal harvest in live donor transplantation. Non-contrast renal MR angiographic (MRA) techniques are potentially well suited to the screening of donors; however, their restricted imaging field of view (FOV) has previously been an important limitation. We sought to assess whether the addition of a large FOV balanced fast field echo (BFFE) steady-state free precession (SSFP) sequence to non-contrast SSFP MRA could overcome this problem. Comparison with contrast-enhanced MRA (CE MRA) and findings at surgery were performed.

METHODS

22 potential renal donors each underwent SSFP and CE MRA. 11 out of 22 potential donors subsequently underwent a donor nephrectomy.

RESULTS

All images were diagnostic. Both SSFP MRA and CE MRA identified an equal number of arteries. Surgery confirmed two accessory renal arteries, both demonstrated with both imaging techniques. A third accessory vessel was identified with both techniques on a kidney contralateral to the donated organ. 6 out of 11 procured kidneys demonstrated early branch arteries at surgery, 5 out of 6 of which had been depicted on both SSFP and CE MRA. The median grading of image quality for main renal arteries was slightly better for CE MRA (p=0.048), but for accessory vessels it was better for SSFP MRA.

CONCLUSION

This pilot study indicates that by combining free-breathing SSFP MRA with large-FOV bFFE images, an accurate depiction of renal vascular anatomy without the need for intravenous contrast administration can be obtained, as compared with surgical findings and CE MRA.

Prevalence of renal artery and kidney abnormalities by computed tomography among healthy adults

BACKGROUND AND OBJECTIVES

Management of incidental renal artery and kidney abnormalities in patients undergoing computed tomography scans is a clinical challenge because their frequency in healthy subjects has not been precisely estimated. Therefore, the prevalence and management of these abnormalities were determined among a large cohort of potential kidney donors undergoing protocol evaluations.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

All patients at the Mayo Clinic who underwent computed tomographic angiography and urography as part of their kidney donor evaluation between 2000 and 2008 were identified. Radiographic reports were abstracted for abnormalities of the renal arteries and kidneys. The prevalence of radiographic abnormalities was stratified by age and gender, and the effect on approval for kidney donation was determined.

RESULTS

Among 1957 potential kidney donors, the mean +/- SD age was 43 +/- 12 years, and 58% were women. The most common abnormalities were kidney stones (11%), focal scarring (3.6%), fibromuscular dysplasia (2.8%), and other renal artery narrowing or atherosclerosis (5.3%). Fibromuscular dysplasia, focal scarring, parenchymal atrophy, and upper tract dilation were more common in women. Renal artery narrowing, focal scarring, and indeterminate masses increased with age. Overall, 25% of potential donors had at least one abnormality. However, these incidental radiographic abnormalities contributed to exclusion from donation in only 6.7% of potential donors.

CONCLUSIONS

Incidental radiographic abnormalities of the renal arteries and kidneys are common. The majority of imaging findings are not perceived to be harmful enough to prevent kidney donation, but future studies are needed to determine their clinical relevance.

Assessment of aortic pathology and peripheral arterial disease using multidetector computed tomographic angiography

The development of multidetector computed tomography represents a remarkable diagnostic advancement because this imaging modality has been widely used in the evaluation of the cardiovascular system. With scanner-adjusted image acquisition and contrast medium administration, multidetector computed tomographic angiography provides a cost-effective and accurate imaging assessment in patients with aortic pathologies or peripheral arterial occlusive disease. Multidetector computed tomographic angiography is associated with several advantages, including high image spatial resolution and rapid imaging acquisition speed. This diagnostic methodology allows accurate detection of a variety of intravascular lesions in the carotid artery, thoracic and abdominal aorta, renal arteries, and peripheral arterial systems. This article provides an overview of multidetector computed tomographic angiography in the assessment of arterial disease and reviews current literature about this diagnostic technology in the evaluation of aortic and peripheral arterial pathologies.

Multidetector computed tomographic angiography of the cardiovascular system

The introduction of multidetector computed tomography (MDCT) is considered a dramatic development in CT imaging that has direct implication in the imaging of various systems, in particular the cardiovascular system. The advantages of MDCT are an enormous increase in imaging acquisition speed, more coverage of the patient, and high spatial resolution. This article reviews the recent developments in CT angiography and discusses the clinical application relevant to diagnosis and endovascular treatment of cardiovascular diseases.