The Effect of Phacoemulsification on the Corneal Endothelium in Diabetic Patients

We compared the structural and functional corneal endothelial changes between patients with non-proliferative retinopathy and age-matched nondiabetic patients after phacoemulsification with posterior chamber lens implantation. Endothelial cell density was calculated preoperatively, and postoperative 4, 8 weeks by specular microscopy. Fluorophotometry to check corneal endothelial barrier function was underwent preoperatively and at postoperative 4 days. Preoperatively, no significant difference in corneal endothelial cell density and corneal endothelial permeability coefficient was noted between diabetic patients and age-matched non-diabetic patients. But the mean increase of corneal endothelial permeability coefficient at 4 days after surgery was 118.13% in diabetic patients and 61.88% in nondiabetic patients (P<0.05). The mean endothelial cell loss at 4 and 8 weeks after surgery were 10. 29%, 12.55% in diabetic patients and 7.05%, 9.39% in non-diabetic patients.(P<0.05)

The Effect of Limbal Transplantation & Cyclosporine A for Chemically Damaged Rabbit Cornea

The authors have evaluated the effect of topically applied 1% cyclosporine A for four weeks after limbal allograft transplantation for ocular surface stability in severely ocular surface damaged rabbits. A total eleven severely damaged rabbits were subdivided into three groups of four limbal autograft (AUTO), three limbal allograft (ALLO), four limbal allograft with topical application of 1% cyclosporine A five times daily for four weeks (ALLO-C). We examined ocular surface smoothness, clarity, corneal vascularization before surgery and three months after surgery, and classified three grade (success, partial success, failure) according to result. In AUTO, three eyes were success, one eye was failure. In ALLO, one eye showed inferior graft detachment and one eye was success, two eyes were failire. In ALLO-C, no graft detachment detected and one eye was success, two eyes were partial success, one eye was failure. We knew that. ALLO-C show more effective ocular surface stability than ALLO. These result suggest ALLO-C can be used as alternative treatment of AUTO in ocular surface reconstruction. But, rnore study for duration and concentration of cyclosporin A will be need.

Clinical Analysis of Penetrating Keratoplasty in Herpes Simplex Keratitis

We conducted a retrospective study of 20 penetrating keratoplasty (19patients) for corneal opacity due to herpes simplex keratitis from January 1992 to February 1997 at National Medical Center. We exaniined f requeuey of graft rejection and recurrence of herpetic keratitis after penetrating keratoplasty. The patients were grouped into control & treatinent, group according to the use of antivirial drug after penetrating keratoplasty and we examined the difference in rate of recurrence between two groups. The follow-up period was from 8 months to 68 months, mean follow-up period being 29.6 months. Graft rejection was seen in 3 eyes out of 20 eyes (15.0%) and recurrence was developed 3 eyes out of 20 eyes (15.0%). Recurrent herpetic keratitis developed in 15.4%(2 of 13) of the eyes in control group and 14.3% (1 of 7) of the eyes in treatment group. There was no statistically significant difference in recurrence rate between two groups (p)0.05). Postoperative prophylactic antiviral treatment is not associated with decreased rate of herpes simplex keratitis recurrence.

Surgical Repair of Traumatic Cyclodialysis with Persistent Hypotony

Cyclodialysis is characterized by a disruption of the circumferential attachment of the fibers of the meridional ciliary muscle to the scleral spur. Cyclodialysis can lead to a marked chronic hypotony. Prolonged periods of hypotony can result in corneal edema, Descemet`s folds, shallow anterior chamber, cataract formation, chorioretinal folds that can involve the macula, and optic disc edema. The authors experienced a case of traumatic cyclodialysis with a persistent hypotony. We have treated with refixation of the detached ciliary body, by direct cyclopexy. Postoperatively, hypotony was disappeared and visual improvement was achieved.

Tear Turnover Rate Measurement Using Fluorotron Master

Maintenance of normal rate of tear production and elimination is essential for the proper controlled envionment for the cornea and the conjunctiva. We analyzed tear turnover rates in normal subjects, which mainly depend on tear production. We scanned 65 eyes of 36 normal subjects after instillation of 2% fluorescein solution 1u into the lower conjunctival fornix, using fluorophotometer (Fluorotron Master). After instillation of fluorescein solution, we scanned the eyes every 3 minutes for 30 minutes to measure tear film fluorescence. We calculated the tear turnover rate using tear film fluorescence valuse. Mean tear turnover rates were 12.3+/-6.6 %/min in normal subjects, 12.7+/-6.9 %/min in men, and 11.7+/-6.6 %/min in women. Mean tear turnover rates of men did not differ significantly from those of women (p>0.05). Mean tear turnover rates of younger subjects(25 years old~40 years old) (16.2 +/-7.4 %/min) were found to be significantly higher than ghose of older subjects(41 years old~73 years old) (9.1+/-40 %/min) (p0.05). We think that this study might be useful to study the diagnosis and treatement of tear secretory system disorders.

The Quantitative Analysis of Autofluorescence in the Aging Crystalline Lens

When illuminated by blue light, the human crystalline lens exhibits green autofluorescence. Autofluorescence of the human lens were analyzed quantitatively in vivo as a function of age in 75 healthy individuals{150 eyes) without cataract, ranging in age from 17 to 63 years. Lenses were scanned through the dilated pupil along the optical axis, generating a fluorescence profile consisting of anterior and posterior peaks of lens, using an automated scanning fluorophotometer(Fluorotron master) coupled with a lens system designed for high resolution of the anterior segment structures. Anterior peak autofluorescence increased linearly by 90 ng fluorescein/ml per decade and posterior peak autofluorescence by 70 ng fluorescein/ml per decade. No significant difference between right and left eyes was demonstrated for anterior or posterior peak autofluorescence. We suggest that the quantitative analysis of the autofluorescence of the human lens might be useful to investigate the changes of the aging lens proteins and the pathogenesis of cataract.

Clinical Results of Phacoemulsification Performed by Ophthalmic Resident

The clinical results and complications of 27 phacoemulsification which had been performed by ophthalmic resident during the learning curve were studied retrospectively. Mean postoperative follow-up period was 8.9 weeks and 82%(22 of 27) was followed up for 4 weeks or longer. Posterior chamber intraocular lenses were implanted in all cases. Final best corrected visual acuity of 0.5 or better was obtained in 21 eyes(95.5%) and mean value of the surgically induced astigmatism was -0.47 diopter of the 22 eyes who were followed up for 4 weeks or longer. The incidence of vitreous loss was 11.1 %(3/27). Of these, two cases occurred during nuclear emulsification, while one case during cortex aspiration. With proper patient selection, meticulous technique, and under the faculty's supervision, phacoemulsification performed by residents during the learning curve can be an effective method for cataract surgery procedure.