Comparison of pharmacokinetic variables for creatinine and iohexol in dogs with various degrees of renal function

Prospective comparison between DCE-MRR and 99m Tc-DTPA-based SPECT for determination of allograft renal function

BACKGROUND

Glomerular filtration rate (GFR) is a preferred indicator of allograft renal function, but direct measurement of GFR remains complicated.

PURPOSE

To prospectively compare dynamic contrast-enhanced MR renography (DCE-MRR) with ^99m Tc-DTPA-based single-photon emission computed tomography (SPECT) for determination of allograft renal function.

STUDY TYPE

Prospective.

POPULATION

Seventy kidney-transplant recipients FIELD STRENGTH: A low-dose DCE-MRR with a 3.0T scanner and a ^99m Tc-DTPA-based SPECT after renal transplantation were performed.

ASSESSMENT

A Baumann-Rudin (BR) and a modified two-compartment model (JZ2C) were used for DCE-MRR analysis. Standard Gate's method was used for SPECT analysis. An endogenous creatinine clearance rate (CCr) constituted the reference standard.

STATISTICAL TESTS

Pearson correlation test and Bland-Altman agreement analysis.

RESULTS

The reference CCr-GFR was 59.58 ± 23.72 mL/min/1.73 m² . GFR determined by eGFR, BR, JZ2C, and SPECT was 90.22 ± 34.38, 36.78 ± 14.46, 48.99 ± 23.88, and 67.32 ± 18.44 mL/min/1.73 m² , respectively. DCE-MRR using JZ2C had the best overall performance, with a Pearson correlation coefficient of 0.81, a bias of -10.58 mL/min/1.73 m² , and a precision of 14.61 mL/min/1.73 m² , as well as high accuracy (30-50% intervals: 74.3-90.0%). Although SPECT had a small bias (7.74 mL/min/1.73 m² ), it had a poor correlation coefficient (0.38), poor precision (23.93 mL/min/1.73 m² ), and low accuracy (64.3-72.3%) as compared with DCE-MRR using JZ2C.

DATA CONCLUSION

DCE-MRR using JZ2C is superior to ^99m Tc-DTPA-based SPECT to determine allograft renal function.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:262-269.