Clinical validation of semi-automated software for volumetric and dynamic contrast enhancement analysis of soft tissue venous malformations on Magnetic Resonance Imaging examination

Abstract

To evaluate venous malformation (VM) volume and contrast-enhancement analysis on magnetic resonance imaging (MRI) compared with diameter evaluation. Baseline MRI was undertaken in 44 patients, 20 of whom were followed by MRI after sclerotherapy. All patients underwent short-tau inversion recovery (STIR) acquisitions and dynamic contrast assessment. VM diameters in three orthogonal directions were measured to obtain the largest and mean diameters. Volumetric reconstruction of VM was generated from two orthogonal STIR sequences and fused with acquisitions after contrast medium injection. Reproducibility (interclass correlation coefficients [ICCs]) of diameter and volume measurements was estimated. VM size variations in diameter and volume after sclerotherapy and contrast enhancement before sclerotherapy were compared in patients with clinical success or failure. Inter-observer ICCs were similar for diameter and volume measurements at baseline and follow-up (range 0.87-0.99). Higher percentages of size reduction after sclerotherapy were observed with volume (32.6 ± 30.7%) than with diameter measurements (14.4 ± 21.4%; P = 0.037). Contrast enhancement values were estimated at 65.3 ± 27.5% and 84 ± 13% in patients with clinical failure and success respectively (P = 0.056). Venous malformation volume was as reproducible as diameter measurement and more sensitive in detecting therapeutic responses. Patients with better clinical outcome tend to have stronger malformation enhancement. • Magnetic resonance imaging readily demonstrates diameters and volumes of venous malformations • MRI diameter calculations are reproducible in estimating the size of venous malformations • But volumetric models of malformations are more sensitive in detecting therapeutic response • Dynamic enhancement is also better assessed with automated volumetric software • Volumetric analysis of malformations offers promise to guide therapy and assess response.