BRAIN BLOOD-FLOW IN ANXIETY DISORDERS - OCD, PANIC DISORDER WITH AGORAPHOBIA, AND POSTTRAUMATIC-STRESS-DISORDER ON 99MTCHMPAO SINGLE-PHOTONEMISSION TOMOGRAPHY (SPET)

Background We compared regional cerebral blood flow (rCBF) in three gr oups of patients with DSM-III-R anxiety disorders. Method Fifteen pati ents with obsessive - compulsive disorder (OCD), 15 with panic disorde r with agoraphobia (PA), and 16 with post-traumatic stress disorder (P TSD) and a similar group of healthy controls were assessed on brain-de dicated high-resolution SPET. Results MANOVA revealed significant rCBF differences between diagnostic groups (F = 4.4; d.f. = 3, 57; P = 0.0 07) and between cerebral regions (F = 6.4; d.f. = 1, 57; P = 0.01) in OCD and PTSD compared with PA and healthy controls, limited to bilater al superior frontal cortices and right caudate nuclei. Whole brain blo od flow correlated positively with anxiety (r = 0.24, n = 46, P = 0.05 ). Beck depression scores correlated significantly negatively with lef t caudate rCBF (r = -0.24, n = 46, P = 0.05) and right caudate rCBF (r = -0.31, n = 46, P = 0.02). PTSD syndrome severity correlated signifi cantly negatively with the Subjects left caudate (r = -0.49, n = 16, P = 0.03) and Recruitment with right caudate rCBF (r = -0.7, n = 16, p = 0.001). Conclusions Functional rCBF differences in anxiety disorders could relate to repetitive, intrusive, distressing mental activity, p rominent in both OCD and PTSD.