Proton Magnetic Resonance Spectroscopy of the Hippocampus and Occipital White Matter in PTSD: Preliminary Results

Abstract

The preliminary results of our study in civilians with PTSD replicate previous MRS studies and are consistent with decreased hippocampal neuronal integrity without effects in the OWM. Replication of our findings is needed.

Magnetic Resonance Imaging and Magnetic Resonance Spectroscopy Study of Deficits in Hippocampal Structure in Fire Victims with Recent-Onset Posttraumatic Stress Disorder

“…For instance, smaller right or left bilateral hippocampal volumes were found with structural MRI in patients suffering from chronic PTSD, such as war veterans or individuals who suffered childhood sexual abuse (5,(7)(8)(9)(10)(11)(12). The reduction in hippocampal neuronal density in patients with chronic PTSD was also noted in research reports that used proton MRS (13)(14)(15)(16). MRS can provide information about alterations in NAA and Cho-containing compounds in the human brain without exposing it to radiation; hence, NAA is considered a putative neuronal marker (17).…”

“…The anterior border of the voxel was located in the most anterior slice that showed hippocampus but not the amygdala. The peaks of spectra were identified according to resonance positions determined by previous studies (14)(15)(16)(17). A radiographer who was blind to the participant diagnoses analyzed the MRS results and identified the peaks from NAA, Cr, and Cho, using Functool 2 (Advantage Windows 4.0 software by General Electric Medical Systems).…”

Neurobiology of PTSD: A Review of Neuroimaging Findings

“…16,17 Reductions in hippocampal volumes have ranged from 5% to 26%, and have tended to be found bilaterally across studies. 18 It should be noted, however, that a number of studies have not replicated the fi nding of decreased hippocampal volumes in PTSD.…”

Magnetic resonance spectroscopy (MRS) and its application in Alzheimer's disease

“…New postprocessing techniques have been developed using anatomical images to take these tissue components into account (89). It is also possible to incorporate voxel tissue composition data into the statistical analysis (90) or correct metabolite concentrations (91). To select a voxel in a desired brain region, it is possible to shift the acquisition grid for MRSI studies.…”

“…Furthermore, Glu is the principal excitatory neurotransmitter in the brain. Using short echo times (TE) techniques, it is possible to measure Glx levels, although until now few studies have examined this peak (90,91,94). Because a considerable amount is known about these neurotransmitter systems, detecting GABA or Glu MRS abnormalities in psychiatric patients would be helpful to understand the underlying biochemical defects and to determine optimal treatments.…”