Clinical Evaluation of Pseudophakic Retinal Detachment

PURPOSE: To evaluate the clinical characteristics of pseudophakic retinal detachment(RD) as RD is the most common sight-threatening complication after cataract surgery. METHODS: We analysed retrospectively the clinical characteristics of 22 pseudophakic RD patiens(23 eyes) which had been operated from January 1993 to December 1997 and followed for 6 months or longer at the Gyeongsang National University Hospital. RESULTS: The average age of the patients was sixty-three and male predominated 19 eyes(82.6%). According as types of IOL implantation included 14 eyes with posterior chamber IOL, 7 eyes with sclera-fixated IOL, 2 eyes with anterior chamber IOL, and 16 eyes(70%) occurred the posterior casule rupture. The interval between IOL implantation and the development of RD was 9.6 months on average and 78% of eyes developed RD within 1 year. In eyes with sclera-fixated IOL, the interval was shorter than others, In cases with ruptured posterior capsule, RD occurred earlier than those with intact posterior capsule. Retinal breaks were principally located in the upper quadrants in 12 eyes(63%) and horseshoe tear was most commmonly encountered. RD involving 3 or more quadrants was observed in 12 eyes(51%) of patients, and macular detachment in 18 eyes(78%). Anatomic success achieved in 83%. The most common cause of the failure was the development of proliferative vitreoretinopathy. Visual results in eyes with ultimate anatomic success of RD repair improved 0.5 or more in 80% if the macula was not involved and in 14.2% if the macula was involved. CONCLUSION: We thought that thorough fundus examination is neccessary during the follow-up of pseudophakic eye with posterior capsule rupture and sclera-fixated IOL after cataract surgery.

Secondary Intraocular Lens Implantation in Pediatric Aphakia

A retrospective study was done on secondary intraocular lens implantation in 19 children(22 eyes)who were not satisfied with aphakic glasses and were not tolerant with contact lenses.In all cases,postoperative visual acuity improved or remained at the preoperative level.In 10 cases,postoperative visual acuity was better than 20/40. After at least 12 months of follow-up,average difference of refractive power between the two eyes in the same patient is 0.79 diopter. Early postoperative complications related to secondary intraocular lens implantation were vitreous hemorrhage(1 eye)and IOL decentration. Vitreous hemorrhage was resorbed in three weeks.In case of IOL decentration,we repositioned the IOL.Late complcations during the follow-up period included development of dense capsular opacification in four eyes.They are all treated by Nd:YAG capsulotomy. After capsulotomy there were some improvement in visual acuity. From these results,secondary intraocular lens implantation appears to be a safe, effective method for correction of aphakic children who are not satisfied with aphakic glasses and/or intolerant of use of contact lenses.

Sequential Argon and Nd : YAG Laser Iridotomies in Angle Closure Glaucoma

A retrospective clinical study to evaluate the use of the argon and Nd: YAG laser in sequential combination for iridotomy was carried out on 29 eyes of 19 patients with angle closure glaucoma. The argon laser settings were standardized at 0.01-0.02 second duration and 50 micrometerspot size. The total mean energies for the argon and Nd: YAG stages were 2.7 +/-1.49J and 9.0 +/-5.83 mJ respectively. Mean postoperative decrease of intraocular pressure(IOP)was 26.4 +/-20.14 mmHg. Postoperative complications were bleeding at iridotomy site (3 eyes),transient increse in IOP (2 eyes),and posterior synechia (1 eye),but there was no lenticularopacity,and no closure of the iridotomy site. The laser iridotomy using sequential argon and Nd: YAG laser is an effective method in dark irides, lowering the mean total energy delivered per eye by the argon and YAG laser repectively, combining the advantages of both laser procedures while avoiding most of the disadvantages. We think that it is the more safe and effective method with the decreased mean total energy of argon laser at 0.01-0.02 second duration, 50 micrometerspot size followed by YAG laser.

The Role of Interleukin-8 in Endotoxin Induced Uveitis

Interleukin-8(IL-8) has been implicates in intraocular inflammation and shown to be a potent chemoattractant for neutrophil, we investigated if IL- 8 has a role in endotoxin induced uveitis(EIU). Mouse monoclonal neutralizing antibody to rabbit recombinant IL-8(gammagammaIL-8)(gammagammaIL-8 and anti IL-8, both generous gifts from Genetech) or mouse IgG2a were given by intravitreal injection to try to modify EIU in New Zealand White rabbits. Antibody to IL-8 tended to reduce aqueous humor cell counts, but the differences were not statistically significant. Anti-IL8 reduced cell counts by 34%(3.8+/-2.9x10(6) cells/ml anti IL-8 treatment vs. 5.4+/-5.5x10 cells/ml IgG2a control, p=0.26 by student t-test). The intravitreal injection of gammagammaIL-8 resulted in a small dose dependent number of infiterating cells in the aqueous and vitreous humor. Taken together, our results cannot exclude a role for IL-8 in acute onset EIU, but the contribution appears to be minor.

Expression of Dopamine D1 and D2 Receptor mRNAs in the Fetal Rat Retina

In this study, the ontogeny of the dopamine D1 and D2 receptors on fetal rat retina was investigated by using in situ hybridization technique. The expression of the D1 and D2 receptor mRNAs showed different pattern of appearance, distribution and density. At gestational day(GD) 13.5, D1 receptor was first detected in neuroepithelium of the retina. Both D1 and D2 receptors were detected at GD 15.5 in the ventricular layer and ganglion cell layer of developing retina of the rat, and D1 receptor showed more strong density than that of D2 receptor. At GD 17.5, Both D1 and D2 receptors were detected in the ganglion cell layer, ventricular layer and pigment epithelium. The labelling density of D1 receptor was higher than that of D2 receptor. At GD 19.5, both D1 and D2 receptors were additionally detected in the optic nuclear layer and plexiform layer. These results imply that D1 and D2 receptor may mediate different important function of the retina.