Quantitative MRI of the mesoesophagus: normative values and anthropometric determinants in healthy participants

Abstract MRI-derived assessment of the mesoesophagus has not been investigated in-vivo. This study aims to establish quantitative MRI-based mesoesophageal parameters. Prospectively, monocentric, 81 healthy participants underwent 3T navigator-triggered T1w-Dixon, 35 participants axial T2w-MRI additionally. Mesoesophageal compartments were segmented and quantified: esophageal length (EL, cm), wall thickness (mm), lumen (EL Vol , cm 3 ), esophageal volume (E Vol , cm 3 ), extra-esophageal mesoesophageal volume (EEM Vol , cm 3 ), total mesoesophageal volume (TM Vol , cm 3 ), the sum of EEM Vol and E Vol , extra-esophageal fat proportion (EEM Fat , %), the ratio of fat-only-signal to the sum of fat-only- and water-only-signal. Median ± IQR, reference intervals (2.5th–97.5th percentiles), multivariable analyses assessing the effects sex, age, BMI, BSA, alongside intra- and interobserver-ICC, cross-sequence concordance, Bland–Altman analysis of T1- and T2-weighted measurements were calculated. 78 participants (60% male, median 54y) were included. EL was 27.2 cm (23.1–31.6 cm), EW 3.8 mm (3.1–5.1 mm), ELVol 0.4 cm3 (0.00-3.50 cm3), EVol 29.9 cm3 (13.4–47.8 cm3), EEMVol 8.2 cm3 (0.7–25.9 cm3), TMVol 36.7 cm3 (18.8–77.3 cm3) and EEMFat 78% (26–91%). BSA predicted EW, EVol, EEMVol and TMVol (p ≤ 0.001). Intra- and interobserver reproducibility of EL was good (ICC ≥ 0.83), with no bias. Demographic and anatomical factors influence mesoesophageal compartments with BSA predicting mesoesophageal volumes, and sex independently predicting volumes except EEM Fat , affording a reference framework for clinical assessment.