Neuroanatomical Changes After Eye Movement Desensitization and Reprocessing (EMDR) Treatment in Posttraumatic Stress Disorder

Several authors have found smaller hippocampal volumes in patients with PTSD and some have suggested that psychotropic drugs may promote hippocampus neurogenesis and reverse the decrease in hippocampus volume. 1 However, the only study that has investigated the effects of psychotherapy on hippocampus volume failed to show a volumetric increase after effective psychotherapy. 2

EMDR is a standardized psychotherapy for amelioration of traumatic sequelae.

We evaluated the hippocampus volumetric changes after successful EMDR treatment of a 27-year-old man with a chronic PTSD related to the suicide of his mother. Written informed consent was obtained after the study procedures had been fully explained. The patient did not receive any medication during the 8 weeks of EMDR treatment. Current and lifetime PTSD diagnoses and severity were established by the Clinician Administered PTSD Scale (CAPS DX) 3 and the severity by the Davidson Trauma Scale (DTS). 4

Morphovolumetric evaluation through high resolution MRI scanning (Philips 1.5T MRI) consisted of coronal T1 Fast Field Echo (matrix 512×512, 1 mm thick) images lying on the plane perpendicular to major hippocampal axis. Hippocampal volume was calculated using dedicated software (Analyze VW 1.16, BIR, Mayo Clinic, MN, U.S.) by manual delimitation of hippocampal shape according to Watson Laboratories, Inc. anatomical criteria on each slice where detected, by an operator blind to subject treatment status. The sum of each area provided right and left hippocampal volumes.

A first bilateral MRI-based measurement of hippocampal volume was obtained at baseline, when the patient met the CAPS criteria for a PTSD diagnosis and the total score on the DTS was 51. The baseline hippocampus volumes were 2,838.91 mm ³ for the left hippocampus and 3,259.00 mm ³ for the right hippocampus. After 8 weeks of EMDR treatment (one 90 minute session/week), the patient no longer met the CAPS criteria for PTSD and the DTS total score had decreased from 51 to 8. The second MRI showed that the left and right hippocampus volumes were 3,196.24 and 3,599.40 mm ³ respectively. Therefore, the increase in hippocampus volume was 357.33 mm ³ (left) and 340.40 mm ³ (right) respectively.

Clearly, our observation in a single case cannot challenge the findings of Lindauer and colleagues, 2 who conducted a randomized clinical trial. Also, the relatively short period of time in which the volumetric increase happened poses the question of whether the increase was due to neurogenesis or may simply be attributable to an increased water and electrolyte content in the hippocampus. However, the magnitude of the volumetric change that we observed after a documented improvement in the PTSD symptomatology suggests the opportunity to not dismiss the question on whether psychotherapy can increase hippocampus volume and possibly have a beneficial effect on neurogenesis, which would be consistent with the hypotheses of several authors, such as Kandel, 5 who have suggested that both psychotherapy and pharmacotherapy may induce alterations in gene expression and structural changes in the brain.