Background: Limited data suggest that scleral buckling procedures may decrease posterior segment blood flow. How this may affect functional outcome remains unknown. Methods: In a prospective, controlled study, color Doppler imaging was used to measure blood flow velocities in the central retinal and ophthalmic arteries of both eyes in patients with unilateral rhegmatogenous retinal detachments before and after primary scleral buckle repair. Encircling elements were used in all patients. Fellow eyes served as controls. Results: Data from six consecutive patients did not show significant preoperative circulatory abnormalities in either artery compared with the controls. There was a statistically significant reduction in mean central retinal artery blood flow velocities of up to 53% in the immediate postoperative period. Ophthalmic artery blood flow velocities, however, did not significantly change after the procedure. Successful retinal reattachment with the expected visual improvement was achieved in all patients with this primary surgery. Conclusions: Scleral buckling procedures with encircling elements decrease blood flow velocities in the central retinal artery but leave the ophthalmic artery unaffected. Good anatomic and functional results still can be achieved despite these hemodynamic changes.