Effect of Ocular Hypotensives and Honan Intraocular Pressure Reducer on Ocular Tension after Retrobulbar Anesthesia

The retrobulbar injection of anesthetic widely used in intraocular surgery will produce anterior displacement of eyeball and a rise in intraocular pressure that may be sufficient to compromise ocular perfusion. We investigated whether ocular hypotensive agent and Honan intraocular pressure reducer which reduced ocular tension before retrobulbar injection effected on lessening the risk of vascular compromise after retrobulbar injection. In the 1st group(15 eyes), no ocular pressure reducing procedure was applied, a mean intraocular pressure immediately after retrobulbar injection was 22.0+/-9.7mmHg. In the 2nd group (14 eyes), using ocular hypotonic agent before retrobulbar injection, a mean intraocular pressure was 13.8+/-4.4mmHg. In the 3rd group (20 eyes), using Honan intraocular pressure reducer, a mean intraocular pressure was 14.2+/-5.2mmHg. The difference in the rise of pressure attributable to retrobulbar injection of group 1 was statistically significant. An it was in only 2 eyes of gorup 1 that hypertension (IOP >35mmHg) which put the eye at risk for vascular occlusion after retrobulbar injection developed. The digital massage for 5 minute following retrobulbar injection produced no statistical difference in intraocular pressure before cataract surgery among all 3 groups. Using ocular hypotensive agents or Honan intraocular pressure reducer before retrobulbar injection may lessen the risk of vascular compromise immediately following retrobulbar injection. And preoperative digital massage for 5 minute may adequately decrease the intraocular pressure for intraocular surgery.

Effect of Premedication and Honan Balloon prior to Cataract Surgery on Intraocular Pressure measured by Tono-pen

With with use of Tono-pen, we investigated the degree of reduction in intraocular pressure of the Honan intraocular pressure reducer(HIPR) with preoperative use of dichlorphenamide and mannitol or without. Seventy five patients scheduled for cataract surgery were divided into 4 groups by preoperative medication. Intraocular pressure was measured before preoperative medication and in process of time after external compression with the Honan intraocular pressure reducer(HIPR) following retrobulbar injection. There was no additive effect on the reduction of intraocular pressure with the preoperative use of dichlorphenamide and mannitol. A rapid initial reduction in intraocular presure over the first 5 minutes of compression was followed by a more gradual reduction from 5 to 20 minutes. We concluded that the compression of up to 20 minutes duration without the preoperative use of dichlorphenamide and mannitol is adequate.