Increased medial orbitofrontal [18F]fluorodopa uptake in Parkinsonian impulse control disorders.

BACKGROUND

Impulse control disorders (ICDs) occur frequently in PD patients.

METHODS

To investigate the possible involvement of the mesostriatal and mesolimbic monoaminergic function in ICDs associated with PD, we examined patients with (n = 10) and without (n = 10) ICDs using the brain [(18) F]fluorodopa PET.

RESULTS

Patients with ICDs (e.g., pathological gambling, hypersexuality, and compulsive eating) showed up to 35% higher [(18) F]fluorodopa uptake in the medial orbitofrontal cortex, compared to control patients, but no differences in the striatum. The results remained significant also after excluding subjects with comorbid psychiatric disorders.

CONCLUSIONS

Increased monoaminergic activity in the medial orbitofrontal cortex might be associated with increased sensitivity for ICDs under dopamine-replacement therapy in PD.