Magnetic resonance signal of hippocampal structure in patients with mild onset depression based on gray scale difference method

Abstract

Objective To identify the minor pathological changes of the hippocampal formation in patients with mild onset depression. Methods The hippocampi of 20 patients with mild onset depression and 20 normal control subjects, collected in our hospital from May 2013 to May 2015, were scanned with magnetic resonance T1 imaging. The gray scale difference method was performed to compare the gray levels of magnetic resonance signal in each part of the hippocampus. Results The hippocampal head, body and tail of two groups could be clearly identified. As compared with those in the normal control group, the maximum value, minimum value and average gray value of magnetic resonance signal in the bilateral hippocampal head of patients with mild onset depression were significantly decreased (P 0.05). Bilateral hippocampal head magnetic resonance signal was not heterogeneous in patients with mild onset depression and the shapes of gray wave curve were abnormal; the local part signal from lateral direction of the hippocampus to the medial (the junction of the amygdala) exhibited a decreased tendency; bilateral hippocampus body and tail magnetic resonance signal gray level curves were not drastically changed. Conclusion There are subtle lesions in hippocampal structure of patients with mild onset depression, which could be exhibited as gray level decreasing in hippocampal head gradually on magnetic resonance images. Key words: Depression; Hippocampus; Magnetic resonance imaging; Gray scale difference method