Z-SCORE BASED INVESTIGATION OF IN VIVO PHOSPHORUS MAGNETIC RESONANCE SPECTROSCOPIC IMAGING PEAKS OF BRAIN TUMORS AT 3T

Objective: phosphorus magnetic resonance spectroscopic imaging (31p-mrsi) provides information about the energy metabolism of brain tumors noninvasively. the aim of this study is to define and assess the z-scores of the in vivo phosphorus magnetic resonance spectroscopic imaging peak ratios of brain tumors at 3t.materials and methods: 31p-mrsi data of thirteen brain tumor patients and five healthy volunteers were retrospectively analyzed. z-scores were defined based on the 31p-mrsi peak ratios obtained from the tumor and normal appearing regions of the brain tumor patients and the healthy volunteers. the peak ratios and the z-scores were compared between these three groups.results: the mean age was 53.2±12.4 years in brain tumor patients, and 34.4±11.6 years in volunteers. in this retrospective study, statistically significantly higher gpc/pcr, gpe/pcr, pi/pcr, pc/pcr, pe/pcr, γatp/pcr, αatp/pcr, βatp/pcr, (gpe+pe)/pcr, and (gpc+pc)/pcr peak ratios were observed in tumor regions than both normal appearing regions of patients and healthy volunteers. the z-scores calculated based on gpc/pcr, pc/pcr, pe/pcr, β-atp/pcr, and (gpc+pc)/pcr peak ratios were statistically significantly higher in brain tumor regions than normal appearing regions.conclusion: as a result of this study, z-scores based on 31p-mrsi peak ratios were defined that might be used as a standardised and objective measure in brain tumor localization, biopsy target definition and followup after treatment