Hippocampal proton MR spectroscopy as a novel approach in the assessment of radiation injury and the correlation to neurocognitive function impairment: initial experiences. Issue 1 (December 2015)

• Record Type: Journal Article
• Authors: Pospisil, Petr; Kazda, Tomas; Bulik, Martin; Dobiaskova, Marie; Burkon, Petr; Hynkova, Ludmila; Slampa, Pavel; Jancalek, Radim
• Is Part Of: Radiation oncology. Volume 10:Issue 1(2015)
• Page Start: 1
• Page End: 8
• Publication Date: 2015-12
• Subjects: Hippocampus -- Radiation injury -- Neurocognitive function -- Magnetic resonance spectroscopy; Cancer -- Radiotherapy -- Periodicals; 616.9940642
• DOI: 10.1186/s13014-015-0518-1
• Languages: English
• ISSNs: 1748-717X

Abstract

Abstract Background The hippocampus is considered as the main radiosensitive brain structure responsible for postradiotherapy cognitive decline. We prospectively assessed correlation of memory change to hippocampal N-acetylaspartate (h-tNAA) concentration, a neuronal density and viability marker, by1 H-MR spectroscopy focused on the hippocampus. Methods Patients with brain metastases underwent whole brain radiotherapy (WBRT) to a dose of 30 Gy in ten fractions daily. Pre-radiotherapy1 H-MR spectroscopy focused on the h-tNAA concentration and memory testing was performed. Memory was evaluated by Auditory Verbal Learning Test (AVLT) and Brief Visuospatial Memory Test-Revised (BVMT-R). Total recall, recognition and delayed recall were reported. The both investigation procedures were repeated 4 months after WBRT and the h-tNAA and memory changes were correlated. Results Of the 20 patients, ten passed whole protocol. The h-tNAA concentration significantly decreased from pre-WBRT 8.9, 8.86 and 8.88 [mM] in the right, left and both hippocampi to 7.16, 7.65 and 7.4 after WBRT, respectively. In the memory tests a significant decrease was observed in AVLT total-recall, BVMT-R total-recall and BVMT-R delayed-recall. Weak to moderate correlations were observed between left h-tNAA and AVLT recognition and all BVMT-R subtests and between the right h-tNAA and AVLT total-recall. Conclusions A significant decrease in h-tNAA after WBRT was proven by1 H-MR spectroscopy as a feasible method for the in vivo investigation of radiation injury. Continuing patient recruitment focusing on other cognitive tests and metabolites is needed.