[Method of studying renal morphology in hypertensive patients with and without renal artery stenosis]

Although the size of the kidney is still the most commonly used as morphological parameter, it is not enough sensitive for early detection of ischemic nephropathy.

To study a novel method of renal morphology analysis using spiral computed tomography angiography (CTA) in hypertensive patients with or without unilateral atheromatous renal artery stenosis (RAS).

Forty-nine hypertensive patients suspected RAS underwent spiral CTA. Arteriography showed significant RAS in 26 patients. Renal length, 3 upper and 3 lower cortical thicknesses were measured in 46 control kidneys (C) i.e. 23 patients without RAS (group 1), in 26 stenosed (S) and in 26 opposite kidneys (OPP) i.e. 26 patients with unilateral RAS (group 2). Mean cortical thickness (MCT), cortical area (CA), medullary length (ML) were calculated in the same groups. The reproducibility and agreement of measurements were investigated in two groups. The demographic parameters (age, sex, bodymass index, and history of hypertension) were correlated with morphological parameters in group 1.

The reproducibility and agreement of measurements were confirmed (R2 = 0.53 to 0.93) except for anterosuperior thickness. The C kidneys were of comparable morphology: MCT (mm) = 9.1 +/- 0.6; 9.2 +/- 1.0, CA (mm2) = 950 +/- 119; 934 +/- 157, ML (mm) = 85 +/- 11. In group of Opp kidneys, MCT = 7.9 +/- 1.4 mm, CA = 806 +/- 210 mm2, ML = 84 +/- 13 mm. In group of S kidneys, MCT = 6.6 +/- 1.6 mm, CA = 612 +/- 193 mm2, ML = 77 +/- 14 mm. Demographic parameters were not correlated to renal morphology.

Spiral CTA is a suitable method to study renal morphology. Cortical thickness and medullary length could be used to obtain a reliable diagnosis of early ischemic nephropathy.