Non-contrast magnetic resonance angiography in renal transplantation and renal donation

TY - BOOK

T1 - Non-contrast magnetic resonance angiography in renal transplantation and renal donation

AU - Blankholm, Anne Dorte

PY - 2015/11/6

Y1 - 2015/11/6

N2 - Renal transplantation is the treatment of choice in cases of severe renal disease. The majority of candidates for kidney transplantation have arteriosclerosis to some extent; thus, preoperative imaging of the vessels is needed. Different imaging modalities are available and are used for this purpose, including US, CTA and CEMRA. CTA is based on x-ray technology, and the applied iodine-based contrast agent can cause nephropathy and, in rare cases, severe allergic reactions. Allergic reactions to Gd used in CEMRA are extremely rare. Thus, CEMRA was often used for preoperative examination before renal transplantation. In 2006, it was realised that the Gd used in CEMRA could cause NSF, which prompted the Danish National Board of Health to produce guidelines for the use of contrast agents in patients with severe renal disease.This thesis discusses different preoperative imaging methods without contrast agents before kidney transplantation and kidney donation.Study I is a review of NCMRA techniques and clinical applications.In study II, we searched for an NCMRA method with consistently good image quality for the examination of the pelvic vessels in patients with severe renal disease. Five different NCMRA sequences were compared with respect to the difference in contrast between the vessels and the surrounding tissue, diagnostic performance and artefacts. We found that the oldest and best-known sequences used for NCMRA, remained the most robust sequences with respect to the measured parameters: RCR, diagnostic quality and artefact burden.Study III searched for an appropriate imaging modality or combination of imaging modalities without use of contrast agents for the examination of candidates for renal transplantation. A comparison of the findings on CT without contrast agent, US and NCMRA with observations from surgery, which served as the reference standard, was performed on candidates for renal transplantation. We found that CT without contrast agent, US or a combination of these two modalities can be used for the preoperative evaluation of candidates for renal transplantation. NCMRA should not be used as the first choice of examination for this purpose because of its low sensitivity in detecting calcification in cases without stenoses.In study IV, we aimed to elucidate whether a MRI protocol without the use of a contrast agent could replace CTA for the preoperative examination of living kidney donors. We compared CTA to an extensive MRI protocol without the use of contrast agents, including NCMRA, and to observations from living donor nephrectomy, which served as the reference standard. We concluded that an optimised MRI protocol without contrast agents could be substituted for CTA for preoperative vessel assessment in living kidney donors.

AB - Renal transplantation is the treatment of choice in cases of severe renal disease. The majority of candidates for kidney transplantation have arteriosclerosis to some extent; thus, preoperative imaging of the vessels is needed. Different imaging modalities are available and are used for this purpose, including US, CTA and CEMRA. CTA is based on x-ray technology, and the applied iodine-based contrast agent can cause nephropathy and, in rare cases, severe allergic reactions. Allergic reactions to Gd used in CEMRA are extremely rare. Thus, CEMRA was often used for preoperative examination before renal transplantation. In 2006, it was realised that the Gd used in CEMRA could cause NSF, which prompted the Danish National Board of Health to produce guidelines for the use of contrast agents in patients with severe renal disease.This thesis discusses different preoperative imaging methods without contrast agents before kidney transplantation and kidney donation.Study I is a review of NCMRA techniques and clinical applications.In study II, we searched for an NCMRA method with consistently good image quality for the examination of the pelvic vessels in patients with severe renal disease. Five different NCMRA sequences were compared with respect to the difference in contrast between the vessels and the surrounding tissue, diagnostic performance and artefacts. We found that the oldest and best-known sequences used for NCMRA, remained the most robust sequences with respect to the measured parameters: RCR, diagnostic quality and artefact burden.Study III searched for an appropriate imaging modality or combination of imaging modalities without use of contrast agents for the examination of candidates for renal transplantation. A comparison of the findings on CT without contrast agent, US and NCMRA with observations from surgery, which served as the reference standard, was performed on candidates for renal transplantation. We found that CT without contrast agent, US or a combination of these two modalities can be used for the preoperative evaluation of candidates for renal transplantation. NCMRA should not be used as the first choice of examination for this purpose because of its low sensitivity in detecting calcification in cases without stenoses.In study IV, we aimed to elucidate whether a MRI protocol without the use of a contrast agent could replace CTA for the preoperative examination of living kidney donors. We compared CTA to an extensive MRI protocol without the use of contrast agents, including NCMRA, and to observations from living donor nephrectomy, which served as the reference standard. We concluded that an optimised MRI protocol without contrast agents could be substituted for CTA for preoperative vessel assessment in living kidney donors.

KW - Magnetic Resonance Angiography

KW - Kidney Transplantation

KW - kidney donation

KW - Computed tomography

KW - Ultrasonography, Doppler

M3 - Ph.D. thesis

BT - Non-contrast magnetic resonance angiography in renal transplantation and renal donation

ER -