Evaluation of New Viscoelatics in Rabbit: Healon, Healon GV, Provisc

Viscoelastic substance which is one of the most important thing in anterior segment surgery sells many kinds as to its unique properties. The complications during its use are acute postoperative intraocular pressure elevation, corneal edema, severe ocular pain, blurred vision. The extent of elevation, peak time and normalized time of intraocular pressure can be varied by operative technique, amount of residual viscoelastics in anterior chamber, kinds of viscoelastics. To compare the safety of Healon GV and Provisc with Healon, we injected the same amount of those three viscoelastics into anterior chamber of 27 rabbits divided by three groups and examined the degree and change of intraocular pressure elevation, corneal edema, intraocular inflammation, maintenance of anterior chamber. Healon GV showed the persistent intraocular pressure elevation immediately after injection and normalized at 24 hours. Healon and Provisc showed elevated pressure at 7 and 5 hour but normalized within 12 hour. Corneal thickness increased significantly at 1 to 7 hour in Healon and Healon GV group and continued to 24 hour in Healon GV group and there was no significant pressure change in Provisc group compared with preinjection status. There were no significant differences in intraocular inflammation, amintenance of anterior chamber between three viscoelastics. Healon GV shoed more frequent, higher intraocular pressure elevation as compared to the other two viscoelastics, but pressure was normalized within 24 hour. From the above results, it is concluded that Healon GV can be used well with caution and Provisc can be used widespreadly due to its minor complication, too.

Clinical Comparison of Three Viscoealsitcs: Healon, healon GV, Provisc

Viscoelastics which are used in intraocular surgery sell many kinds as to its unique properties. We intended to valuate the clinical usefulness of three viscoelastics, Healon, Healon GV and Provisc. We performed phacoemulsificatioin and posterior chamber intraocular lens implantation in 26, 28, 29 eyes with each viscoelastics and measured the corneal thickness at preoperatively, postoperative 1 day, 1 week, 1 month, 2 months, 5 months and endothelial cell count at preoperatively, postoperative 2 months. We also analysed the anterior chamber maintenance and easiness of injection and removal during operation, In Healon used group, Preoperative corneal thickness was 549.7+/-24.3micrometer, in Healon GV group, 550.1+/-28.7micrometer, in Provisc group, 543.1+/-39.0micrometer and which were changed into 552.1+/-39.0micrometer, 533.1+/-21.1micrometer, 522.2+/-32.0micrometer at postoperative 5 months respectively, but there was no statistically significant difference between preoperative and postoperative status in all three groups. There was a tendency of slight reduction of endothelial cell count at postoperative 2 month in three groups, but it wasn`t statistically significant, too. Healon GV and Provisc were better in anterior chamber maintenance but injection into anterior chamber and removal by irrigation and aspiration were more easy in Healon used group. So, we suggest all three viscoelastics has hood endothelial protective effect and can be used freely as to their unique properties and the operative situation.

The changes of Corneal Endothelial Morphology after Phacoemulsification by using Healon GV of Viscoat

Corneal endothelial cell damage from phacoemulsification has been attributed to mechanical injury caused by surgical manipulation and oxygen free radicals produced by ultrasound. We evaluated role of protective effect in Healon GV and Viscoat on corneal endothelial cell damage during phacoemulsificatin Seventy five eyes underwent phacoemulsigication hrough scleral tunnel incision with posterior chamber lens implantation.: Healon GV, 32 eyes and Viscoat, 43 eyes. We analyzed the corneal endothelial morphology using non-contact specualr microscope and analysis program.The percent loss of corneal endothelial density at 3 months postoperative period was greater in Viscoat(5.87%) than in Healon GV(2.47%),although it was not statistically significant(p>0.1). Coefficient of variation in cell size and hexagonality of the corneal endothelial cells also showed no significant difference between the two groups(p>0.1). In conclusion, Healon GV and Viscoat have similar protective effect on the corneal endothelial cell damage induced by ultrasound during phacoemulsification.