ARTICLE: PDF OnlyRegional cerebral blood flow changes after light therapy in seasonal affective disorderMATTHEW, E.1*; VASILE, R. G.2; SACHS, G.3; ANDERSON, J.2; LAFER, B.2; HILL, T.1 Author Information Departments of 1Radiological Sciences and 2Psychiatry, Deaconess Hospital and Harvard Medical School, Boston, MA and 3Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA *Address all correspondence to Elizabeth Matthew, Department of Radiological Sciences, Deaconess Hospital, 1 Deaconess Place, Boston, MA 02215, USA. Nuclear Medicine Communications 17(6):p 475-479, June 1996. Buy Abstract Summary There is considerable evidence to indicate that depressive disorders may be associated with changes in regional cerebral blood flow (rCBF), and that successful treatment may reverse these changes. We studied patients with seasonal affective disorder (SAD) using 99Tcm-hexamethylpropylene amine oxime (99Tcm-HMPAO) single photon emission tomography (SPET) to examine the effect of light therapy on rCBF. Ten depressed patients (8 females, 2 males) with a mean (± s.d.) age of 33.5 ± 11.3 years underwent 99Tcm-HMPAO SPET studies before and after light therapy. The treatment response was evaluated using the Structured Interview Guide for the Hamilton Depression Rating Scale - Seasonal Affective Disorders Version (SIGH-SAD). A patient was considered responsive to light therapy if the post-treatment SIGH-SAD score was reduced by 60% or more in comparison to the pre-treatment score (responders, n = 5; non-responders, n = 5). Pre- and post-treatment SIGH-SAD scores and SPET data were compared in each patient. An improvement in depressive symptoms after light therapy was associated with an increase in rCBF in the frontal and cingulate regions as well as the thalamus. Such changes were not seen in non-responsive subjects. © Lippincott-Raven Publishers.