Tc-99m HMPAO brain SPECT in stroke patients with negative symptoms

Abstract

We have recently shown that certain patients with strokes suffer from a negative symptom complex similar to that seen in schizophrenia and which is distinct from depressive symptoms. The purpose of the current study was to evaluate brain peffusion patterns in stroke patients with negative symptoms in order to examine the functional neuroanatomy which might underlie this syndrome. Sixteen patients, aged 51-82, were divided into two groups: those with negative symptoms (NS group, Positive and Negative Symptom Scale, Negative Symptom Subscale (PANSS-N) total score _> 15, n = 7) and those without negative symptoms (PANSS-N >15, n ~ 9). Each patient underwent a SPECT scan using Tc-99m HMPAO and ADAC single-head SPECT camera. Images were analyzed by two raters who were blind to the presence or absence of negative symptoms. Striatal, posterior frontal, and anteromedial frontal regions of interest (ROIs) were symmetrically defined in each hemisphere. Cerebellar ROls were selected in the middle portion of each cerebellar hemisphere. Cortical to cerebellar perfusion ratios were established semiquantitatively, and group differences were analyzed. Patients in the NS group had significant asymmetry in striatal perfusion (Mann-Whitney U = 38, p = 0.08) and in perfusion in the anteromedial frontal cortex (Mann-Whitney U = 8, p = 0.03). The correlation between these two values was not significant. These results are consistent with the involvement of the striatum and anteromedial frontal cortex in the etiology of negative symptoms.