Metabolic activity in the pituitary gland may be able to differentiate between patients suffering from mild traumatic brain injury (TBI) and post traumatic stress disorder (PTSD) and patients with mild traumatic brain injury alone.
The research, which was presented at the Radiological Society of North American centennial meeting, could have major implications for the armed forces, as the location of the pituitary gland puts it at greater risk of damage from blast-related trauma incurred during combat.
Metabolic activity in the pituitary gland was measured using positron emission tomography (PET) and computed tomography (CT) scans and reviewed by Osama Raslan, MD, MBCh, of Saint Louis University Hospital, and colleagues. The researchers found that metabolic activity in the pituitary gland was significantly higher in patients with both TBI and PTSD, with an average standardized uptake value mean (SUVmean) score of 3.08, compared to patients with only mild TBI, who averaged an SUVmean score of 2.54. Additionally, the SUVmax from the hypothalamus was significantly lower in TBI-only patients compared to controls.
The researchers followed standard imaging protocols, including collecting the PET and CT scans in the morning followed by MRI scans of the brain to ensure all were structurally normal. Patients with TBI were stratified by severity according to criteria from the Department of Defense and Veterans Affairs Consensus Definition. The scans were reviewed by a neuroradiologist and nuclear medicine physicians.
During his presentation, Raslan noted that the research may be the first to connect pituitary dysfunction to PTSD symptoms in people with mild TBI, and that resulting hormonal abnormalities may account for the PTSD symptoms.
However, Max Wintermark, MD, of Stanford University Medical Center, who moderated the press conference, said that the study’s results are preliminary and are limited by the small sample size, according to MedPage Today.
- Raslan O, et al “The value of 18F-FDG PET/CT in hypothalamic-pituitary-adrenal axis in differentiation of blast-related mild traumatic brain injury and post-traumatic stress disorder (PTSD) from blast related mild Tbi alone in a post-acute veteran population” RSNA 2014; Abstract SSE19-01. Available here: http://rsna2014.rsna.org/pdf/Nuclear%20Medicine.pdf