The Honan Intraocular Pressure Reducer (HIPR) was applied to rabbit eyes for 30 min at pressure settings of 0, 30, 50, or 100 mmHg. Ocular blood flow was measured using (85Sr) radioactively labelled 15 micron microspheres either with the HIPR applied to the eye or 15 min after removal. Intraocular pressure was measured before applying the HIPR, immediately after removal, or 15 min after removal. At all pressure settings, the HIPR significantly lowered the IOP (P less than or equal to 0.05) both immediately and 15 min after removal. At all pressure settings, except 0 mmHg, blood flow was significantly (P less than or equal to 0.05) both immediately and 15 min after removal. At all pressure settings, except 0 mmHg, blood flow was significantly (P less than or equal to 0.05) lower with the HIPR applied compared to 15 min after removal.