The Effect of Antimetabolites for Inhibiting the Proliferation of Rabbit Lens Epithelial Cells in Vitro

The most common cause of blurred vision after extracapsular cataract extraction is known to be an opacification of the posterior lens capsule. The pathogenesis of posterior lens capsule opacification is primarily caused by residual lens epithelial cells. For the prevention of posterior capsular opacification, several kinds of anti-mitotic drugs is being actively investigated. But the antimitotic drugs are not clinically used due to toxicity towards the intraocular tissues. The objectives of this study is to evaluate the effect of mitomycin C and tirilazad mesylate(FREEDOX(TM)) respectively for inhibiting the proliferation of rabbit lens epithelial cells when it is administered in a short period. Lens epithelial cells from white rabbits were harvested andcultured for 4 passages. Mitomycin C was applied for 3 minutes with 0.025mg/ml and 0.05mg/ml in concentration respectively. The proliferation assay was performed by [(3)H]-thymidine uptake test. Significant decrease of lens epithelial cell proliferation appeared in both drugs.When Mitomycin-C was applied with 0.025mg/ml for 3 minutes, cell proliferation was reduced to 31.5% compared with control and in 0.05mg/ml concentration, to 12.5%. When tirilazad mesylate was applied 0.15mg/ml for 3 minutes, cell proliferation was reduced to 46.5% compared with control and in 1.5mg/ml concentration, to 7.5%. If futher investigation would show the effectives and safety of these drugs, these agents could be applied into the lens capsular bad at the time of surgery to prevent the posterior capsular opacification after cataract surgery.

Postoperative Ptosis after Cataract and Glaucoma Surgery

A retrospective study was done on 189 eyes of 156 patients who underwent cataract and/or glaucoma surgery to evaluate the effect of surgical technique, operation time, age of patients, mitomycin C use and superior rectus muscle injury on the incidence of postoperative ptosis. Interpalpebral fissure and levator funtion were measured preand postoperatively. All patients had topical and pin-point anesthesia. For the cataract patients, wire speculum was used and traction suture on superior rectus muscle was performed with 4-0 black silk. For the glaucoma patients, plate speculum was used and traction suture on superior rectus muscle was performed with 6-0 black silk. Decrease of the interpalpebral fissure over 2mm were observed in 7 of 115 eyes (6.0%) in cataract surgery, 5 of 51 eyes (9.8%) in glaucoma surgery and 3 of 23 eyes (13.0%) in triple surgery for cataract and glaucoma at postoperative 6 months. The variables significantly infuencing the incidence of ptosis were as follows; age of the patients (more than 50 years old. relative risk=1.7), operation time (more than 40 minutes, R.R=2.3) and mitomycin C use (R.R.=1.9). Development of superior rectus hematoma during the traction suture did not affect the incidence of postoperative ptosis.

The Effect of Probing for Congenital Nasolacrimal Duct Obstruction

Congenital nasolacrimal duct obstruction is a major cause of epiphora in infants and the incidence is known to be 1.75% to 12.5%. Debates continues about optimal management for patient`s age. Both early intervention and late intervention have advantages and disadvantages. This study was designed to evaluate the effect of probing for congenital nasolacrimal duet obstruction in association with the patient` s age to decide the optimal timing for probing. From January 1993 to November 1996, 85 eyes of 68 patients were diagnosed as congenital nasolacrimal duct obstruction and had probing under topical anesthesia. The success of probing was defined as improvement of symptoms for at least 4 weeks of period after probing. The probing was successful in 73 out of 85 eyes and the success rate was 85.8%. The success rate of infants between 3 to 9 months of age was 92.6%. The success rate of infants older than 10 months of age was 74.2%. The difference between two groups was statistically significant(P<0.05). The success rate of probing for congenital nasolacrimal duct obstruction was highly associated with the age and it began to decrease when the age of the patient was over 10 months. Therefore it is recommendable to probe for congenital nasolacrimal duct obstruction before the age of the patient reaches 10 months.

Factors Affecting Compliance with Prescribed Eyedrops for Glaucoma

Taking eyedrops according to prescription is an important factor in the management of glaucoma. In this study, we investigated th causes, forms, and sociological variables associated with patient noncompliance and measures to improve compliance. We surveyed 184 patients using eyedrops as prescribed for glaucoma to evaluate compliance. The frequency of missing eyedrops were as follows. Fifty patients missed taking eyedrops more than once per week, 17 missed once per 2 weeks, therefore, 39% of the total patients missed taking eyedrops more than once per 2 weeks. We defined the good compliance group as those who missed taking eyedrops once or less per month and inquired into the factors affecting compliance. Lesser frequency of taking eyedrops and no experience of side effects, resulted in good compliance, whereas age, sex, duration of disease, the standard of living, understanding the doctor's prescription, marital status, and fear of blindness did not affect compliance. Regarding understanding the doctor's prescription, 74.7% of the patients answered 'fully understood', however, 64.3% of the patients answered 'No' when questioned 'Did you press your punctum or close your eyes for five minutes after taking eyedrops?' showing discrepancy between performance and understanding the doctor's prescription. Therefore, we have to make to make an effort to promote compliance by considering these factors in treatment of glaucoma patients.