The Effect Intravitreal Dexamethasone and Antibiotic Therapy after Vitrectomy

Bacterial endophthalmitis is an ocular emergency that requires rapid diagnosis and therapeutic decision making. The introdection of intravitreal injection of antibiotics has been a major advancement because it has resulted in a marked improvement in visual outcome. The intravitreal injection of steroids may be potentially useful in the treatment of endophthalmitis and other ocular inflammatory diseases. Forty eyes of pigmented rabbits were used, and divided into two groups. Group I was eyes without vitrectomy. In the right eye, 100 microliter of 1mgvancomycin, 400 microliter amikacin and 400 microliter dexamethasone injected was done. Group II was eyes with vitrectomy and lensectomy. At 2 weeks after lens and vitreous removal, rabbit eyes received an injection of a combination of 1mg vancomycin, 400 microliter amikacin and 400 microliter dexamethasone in right eye and BSS in left eye. The effect of combination injection was examined by light and transmission, scanning electron microscope at 3 days, 1 week, 2 weeks and 6 weeks following injection. The injection of combination without vitrectomy produced no toxicity. After injections of either combination or BSS after vitrectomy, macrophages were observed on the surface of retinal pigment epithelium and disorganized outer segments. This finding seems to be produced by vitrectomy procedure rather than drug toxicity. These results supports the hypothesis that the injection of these combinations is not toxic to aphakic/vitrectomized eyes.

Improved Culture Method of Retinal Pigment Epithelial Cells and Functional-morphological Characteristics In Vitro

To study the isolation and purification and proliferation of the cell in cell culture system, and to develop an improved culture method by a modified cell isolation technique and modified culture medium. The RPE cells were cultured in 3 different mediums: type I(MEM medium with 20% FCS) type II(F-10 medium with 20% FCS) and type III(DMEM medium with 10% FCS, EGF, hydrocortisone, insulin, ethanolamine, phosphoethanolamine, chorea toxin, triiodotyronine, adenine, transferrin and BPE). We compared population doubling(P.D.), population doubling time(P.D.T), morphologic changes and phagocytic activity during a 7week period. Rapid proliferation and high purity of retinal pigment epithelial cells(RPE cells) showed in type III culture medium. Type III culture medium presented the best results in P.D., P.D.T. and cell purification. In type III culture medium, single RPE cells produced about 6 X 10(7) RPE cells in the 7week period and morphology and phagocytic activity were well maintained, when UV-B irradiation at RPE was used to produce melanin, it had no effect, but the RPE cell was inhibited by UV-B irradiation. This improved culture method for RPE cells will provide a good in-vitro model for the studies of biochemistry, cellular function of the RPE cell, as well as its clinical application in eye disease.

Comparison of Betamethasone Concentration in Aqueous Humor Between Upper and Lower Fornix Subconjunctival Injection After Lens Delivery

The purpose of this paper is to investigate the difference in concentration of 0.53% betamethasone in aqueour humor after betamethasone subconjunctival injection on upper and lower fornix after cataract extraction. A total of 8 rabbits were used. Cataract extractions were performed with the cryoprobe. After 6 hours, 0.53% betamethasone was subconjunctivally in upper fornix of the left eye and injected in lower fornix of the right eye. The control group of 3 rabbits underwent with the same procedures but the without lens delivery. the concentration of 0.53% betamethasone in aqueous humor was measured with HPLC(High Performance Liquid Chromatograph) after fine needle aspiration of aqueous humor. The results obtained were as follows. 1. In 5 eyes of the control group in 3 rabbits, 0.53%betamethasone was injected subconjunctivally on the lower fornix. The mean concentration of 0.53% betamethasone in aqueous humor was 0.544 +/- 0.0818 microgram/ml. 2. After 0.53% betamethasone subconjunctival injection on upper fornix after lens extraction, the mean concentration of 0.53% betamethasone in aqueous humor was 0.318 +/- 0.0117 microgram/ml. 3. After 0.53% betamethasone subconjunctival injection on lower fornix agter lens extraction, the mean concentration of 0.53%betamethasone in aqueous humor was 0.702 +/- 0.0332 microgram/ml. 4. The mean concentration of the betamethasone in aqueous humor after 0.53% betamethasone subconjunctival injection on lower fornix after lens extraction was significantly higher than on upper fornix(p<0.05).

Clinical Observation on Reconstruction of the Contracted Anophthalmic Socket by the Dermis-fat Graft

The various method have been used in reconstruction of the anophthalmic socket. Dermis-fat graft as an orbital implant is a relatively new approach. Dermis-fat graft restores the volume lost by enucleation, gives additional conjunctival lining and is permanent, with a minimal chance of absorption. Dermis-fat graft was used in reconstruction of an ophthalmic socket in our hospital. We found it successful procedure in case of primary enucleation, because it is permanent and it preserves the conjunctiva.