Investigation of the Relationship Between Preoperative and Postoperative Renal Volume and Renal Function in Living...

Living donor nephrectomy (LDN) leads to an immediate reduction in nephron mass, triggering compensatory hypertrophy in the remaining kidney. However, the relationship between changes in renal volume and functional adaptation remains unclear. This study aimed to evaluate the association between pre- and postdonation renal volume and renal function in living kidney donors (LKDs).

We retrospectively reviewed 23 LKDs who underwent postdonation computed tomography (CT) imaging following LDN between 2011 and 2021. Contralateral renal volume (CRV) was measured using 3D reconstructions from CT scans. The CRV change ratio was defined as postdonation CRV divided by predonation CRV. Estimated glomerular filtration rate (eGFR) was assessed before and after donation. Correlations between renal volume parameters and renal function were analyzed.

All donors exhibited increased CRV postdonation, with a median change ratio of 1.32. The CRV change ratio positively correlated with predonation eGFR (ρ = 0.449, p = .031), predonation volume (ρ = 0.491, p = .019), and postdonation eGFR (ρ = 0.619, p = .002). Donors with larger predonation kidney volumes had significantly better postdonation function and greater volume increases.

CT-based volumetry demonstrated significant compensatory hypertrophy in the remnant kidney following LDN, with the degree of volume increase closely associated with both pre- and postdonation renal function. Predonation renal volume may serve as a useful predictor of functional recovery. These findings support the clinical utility of CT volumetry for donor assessment and long-term follow-up. Further prospective studies are warranted.