EX-VIVO PHOSPHORUS MAGNETIC-RESONANCE SPECTROSCOPY ON EYE BANK CORNEAS AND CORNEAL METABOLIC HEALTH

Background: Since a potential exists for untoward effects on the corne a from the high magnetic fields and radio-frequency energies, and the further manipulation required for phosphorus-31 magnetic resonance spe ctroscopy (P-31-MRS), we determined the effects of this technology on tissues using paired human corneas (n=4) meeting criteria acceptable f or transplantation. Methods: Slit-lamp biomicroscopy, pachometry, spec ular microscopy, and redux fluorophotometry were performed on all corn eas. One cornea of each pair was examined (<30 min) by P-31-MRS. Follo wing P-31-MRS, slit-lamp biomicroscopy, pachometry, and redox fluoroph otometry were again performed. Results: Data tabulated included the P- 31 energy modulus (1.37+/-0.28), the ATP/Pi (2.92+/-0.59) and SP/Pi (0 .76+/-0.04) ratios, and the intracorneal pH (7.24 +/-0.09). Conclusion : Since there were no significant differences in slit-lamp biomicrosco py, endothelial density and morphometry, cell counts, and pachometric and redox fluorophotometric measurements be tween corneas of each pair before and after P-31-MRS analysis, it was concluded that there was n o detectable metabolic damage secondary to such analysis. This study s uggests that MRS analysis of human eye-bank tissues does not damage th e cornea metabolically and may provide a practical evaluation of the h ealth of the cornea at the biochemical level.