Age and Gender Differences in Morphometric Measurements of Brain Stem Using Magnetic Resonance Imaging in Healthy Indian Adults

Abstract

Background: Morphometric changes in the brain stem can be an early indicator for ongoing physiological or pathological changes. Establishing age‑ and gender‑matched linear morphometric values of the brain stem serves as a useful reference for comparison. Aims and Objectives: This study aimed to determine normal measurements of brain stem structures in healthy Indian adults and to establish age and gender differences in brain stem measurements if any. Materials and Methods: This hospital‑based cross‑sectional study was conducted from November 2020 to January 2021 on patients referred to the department of radiodiagnosis for magnetic resonance imaging (MRI) of the brain. Baseline data and linear midsagittal measurements on MRI were recorded. Results: A total of 142 patients were included in the study. The average measurements for midbrain, pons, medulla at pontomedullary (PM), and medulla at cervicomedullary junction are 1.67 ± 0.17 cm (mean ± standard deviation [SD]), 2.16 ± 0.18 cm (mean ± SD), 1.39 ± 0.16 cm (mean ± SD), and 1.08 ± 0.13 cm (mean ± SD), respectively. Significant reduction in brain stem measurements at all levels with P < 0.05 were recorded with increase in age except for the medulla at the PM junction which remained constant. There was no significant difference in brain stem measurements between males and females. Conclusion: Normal reference value for AP diameter of the brain stem in healthy Indian adults showed statistically significant reduction at various levels with advancing age. There were no statistically significant gender differences in sagittal diameter of the midbrain, pons, and medulla.