title: The magnetic resonance renogram in renal transplant evaluation using dynamic contrast-enhanced MR imaging.
abstract: To assess the role of the dynamic gadolinium DTPA (Gd-DTPA) magnetic resonance (MR) renogram in differentiating various causes of renal allograft dysfunction, contrast-enhanced MR imaging studies were performed in 5 normal renal allografts, 5 patients with acute rejection (AR), and 7 patients with cyclosporine nephrotoxicity. Time-versus-signal intensity (SI) curves were plotted. Normal renal allografts showed a rapid increase and slow decay, with a definite peak in cortical (CX) SI curves (peak mean signal intensity (Amax 338.6 +/- 46.5). The outer medullary (OM) (Amax 306.5 +/- 59) and inner medullary (IM) (Amax 263.4 +/- 47.4) curves did not show a definite peak. The OM curve slowly reached a steady state and caught up with the CX curve. AR episodes were characterized by a blunted uprise and delayed peak of CX (Amax 180 +/- 70.9) and a low-amplitude vascular phase with a slow constant uprise of the inner medullary curve (Amax 120.35 +/- 42.4). The OM signal intensity curve (Amax 150.73 +/- 78) failed to catch up with the CX curve. The maximum amplitude of SI curves in CsA-induced allograft dysfunction were low, with no definite peak, and CX, OM, and IM curves ran parallel to each other with a constant gap. Dynamic Gd-DTPA, MR imaging is a noninvasive technique that shows distinct characteristics in acute rejection, cyclosporine nephrotoxicity, and normally functioning renal allografts.
authors.affiliation: Department of Nephrology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
authors.forename: R K
authors.initials: RK
authors.lastname: Sharma
authors.forename: R K
authors.initials: RK
authors.lastname: Gupta
authors.forename: H
authors.initials: H
authors.lastname: Poptani
authors.forename: C M
authors.initials: CM
authors.lastname: Pandey
authors.forename: R B
authors.initials: RB
authors.lastname: Gujral
authors.forename: M
authors.initials: M
authors.lastname: Bhandari
mesh_terms: D000328:Adult; D001706:Biopsy; D003287:Contrast Media; D016572:Cyclosporine / Q000009:adverse effects / Q000633:toxicity; D005260:Female; D005682:Gadolinium; D019786:Gadolinium DTPA; D006084:Graft Rejection / Q000175:diagnosis; D006801:Humans; D007674:Kidney Diseases / Q000139:chemically induced; D016030:Kidney Transplantation / Q000276:immunology / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D009942:Organometallic Compounds; D004369:Pentetic Acid / Q000031:analogs & derivatives; D011866:Radioisotope Renography / Q000379:methods*; D014184:Transplantation, Homologous / Q000473:pathology
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D004369:Pentetic Acid; D016572:Cyclosporine; D005682:Gadolinium; D019786:Gadolinium DTPA