RENAL ANATOMIC CHANGES ON MAGNETIC-RESONANCE-IMAGING AND GADOLINIUM-ENHANCED MAGNETIC-RESONANCE ANGIOGRAPHY AFTER RENAL REVASCULARIZATION -ORIGINAL INVESTIGATION

RATIONALE AND OBJECTIVES. The anatomic and hemodynamic renal changes a fter renal arterial revascularization (TZAR) were investigated. METHOD S. Thirty-seven kidneys and 40 renal arteries were evaluated in 20 pat ients by using magnetic resonance imaging/magnetic resonance angiograp hy (MRI/MRA) to assess pre- and post-PAR renal length and mass, parenc hymal thickness, renal enhancement, renal artery caliber, poststenotic dilation, and signal dephasing on 3D phase contrast (PC). The kidneys and renal arteries were segregated into three groups. Group 1 include d 16 patients who benefited from RAR (defined as clinical improvement based on decreased serum creatinine or fewer number of antihypertensiv e medications) in whom 26 renal arteries in 25 kidneys were studied. I ntervention included renal artery endarterectomy (n = 20); aortorenal bypass (n = 3); renal artery reimplantation (n = 3); and percutaneous transluminal angioplasty (PTA; n = 1), A total of 27 interventions was performed, as PTA failed for one patient who subsequently underwent a ortorenal bypass before reimaging, Group 2 included four patients who did not clinically benefit. A total of eight revascularized arteries w ere studied in seven kidneys. In group 3, six renal arteries in five k idneys from groups I and 2 without RAS/RAR were analyzed as an interna l control. RESULTS. Technical success (defined as increased vessel cal iber after intervention) was achieved in 33 of the 34 revascularized a rteries. A statistically significant increase in renal length occurred regardless of clinical outcome (pre-RAR, 9.5 cm; post-RAR, 10.5 cm: P < 0.0001). Parenchymal thickness and renal mass, however, improved on ly in patients who benefited clinically from RAR. Parenchymal enhancem ent was unchanged in any of the groups studied. No significant morphol ogic changes were detected in the control group. CONCLUSIONS. Magnetic resonance imaging and Gd-h IRA detect anatomic and hemodynamic change s that occur with renal revascularization.