MR Spectra of Normal Adult Testes and Variations with Age: Preliminary Observations

Objectives The aim was to determine the proton MR (1H-MR) spectra of normal adult testes and variations with age. Methods Forty-one MR spectra of normal testes, including 16 testes from men aged 20–39 years (group I) and 25 testes from men aged 40–69 years (group II), were analyzed. A single-voxel point-resolved spectroscopy sequence (PRESS), with TR/TE: 2000/25 ms was used. The volume of interest was placed to include the majority of normal testicular parenchyma. Association between normalized metabolite concentrations, defined as ratios of the calculated metabolite concentrations relative to creatine concentration, and age was assessed. Results Quantified metabolites of the spectra were choline (Cho), creatine (Cr), myo-inositol (mI), scyllo-inositol, taurine, lactate, GLx compound, glucose, lipids, and macromolecules resonating at 0.9 ppm (LM09), around 20 ppm (LM20), and at 13 ppm (LM13). Most prominent peaks were Cho, Cr, mI, and lipids. A weak negative correlation between mI and age ( P = 0.015) was observed. Higher normalized concentrations of Cho ( P = 0.03), mI ( P = 0.08), and LM13 ( P = 0.05) were found in group I than in group II. Conclusions 1H-MR spectra of a normal adult testis showed several metabolite peaks. A decrease of levels of Cho, mI, and LM13 was observed with advancing age. Key Points • Single-voxel PRESS MRS of a normal testis is feasible. • 1H-MR spectra of a normal testis showed several metabolite peaks. • Most prominent peaks were Cho, Cr, mI, and lipids. • A decrease of Cho, mI, and LM13 was seen with advancing age.