Postoperative Recurrence Rate of Scleral Fixation Technique and Bare Scleral Technique in Primary Pterygium Operation

Pterygium is a common surgical ocular disease which recurs frequently postoperatively. Numerous different techniques have been developed for the successful surgical treatment of pterygium. It was theorized that the pterygium recurrence after surgery would be prevented if scar tissue is formed on the bare sclera and if the corneal epithelium heals before the conjunctival epithelium reaches the limbus. We compared the recurrence rate of pterygium and complications after bare sclera technique with those after scleral fixation technique by which remaining conjunctiva was anchored tightly to the adjacent sclera with sutures. In the first group, 94 patients (103 eyes) operated by scleral fixation technique were composed of 45 male and 49 female. Their mean age was 57.2+/-9.7 years and mean follow-up period was 12.50+/-2.53 months. In the second group, 96 patients(101 eyes) operated by bare sclera technique were composed of 47 male and 49 female. Their mean age was 56.3+/-9.2 years and mean follow-up period was 12.12+/-2.41 months. The recurrence rate was 9.7%(10 eyes) in scleral fixation technique group and 32.7%(33 eyes) in bare sclera technique group. This difference was statistically significant(p<0.05). A case of postoperative scleromalacia was observed in the former group. The scleral fixation technique (as modified bare sclera technique) seems to be more effective for reducing postoperative recurrence of primary pterygium than simple bare sclera technique.

Posterior Capsule Opacification and Intraocular Lens Design with In-the-bag fixated Posterior Chamber Lens

This study was performed to evaluate the correlationship between posterior capsular opacification and optic configuration of intraocular lens in extracapsular lens extraction with In-the-bag implantation of posterior chamber lens. We retrospectively studied the 455 cases of cataract operations that were performed between January 1993 and January 1995. All were in-the-bag placement and their optic designs were divided into two groups: a group of biconvex lens and a group of convex-plano lens with continuous laser ridge. The incidence of PCO in bicovex lens group was 7.0% and that of convex plano lens with laser ridge group was 7.1%. The difference in the rate of posterior capsular opacification between two groups was not statistically significant. The incidence of Nd: YAG laser posterior capsulotomy revealed 0.0% in continuous ridged group and 2.6% in biconvex group(p>0.05).

The Effect of Holmium:YAG Laser Thermokeratoplasty on Corneal Astigmatism in Rabbits

This animal study was conducted to investigate the effect of holmium:YAG laser thermokeratoplasty on correction of hyperopic astigmatism. A pulsed holmium:YAG laser emitting a wavelength of 2.06 micrometer was used. Arcuate, reverse arcuate, linear patterns of laser burn were applied along the flat corneal meridian and their effects on the rabbit corneal curvature were studied. Keratometric measurements and cycloplegic refractive error were determined preoperatively, one, two, and three months after operation. The changes of refractive astigmatism in three patterns of laser burn were 0.8130, 3.0243, 0.8437 diopter, respectively, compared to that of the control group on postoperative three months. The changes of keratometric astigmatism were 1.1719, 3.0737, 0.7812 diopter, respectively, compared to that of the control group on postoperative three months. We found that holmium:YAG laser thermokeratoplasty is effective in steepening flat corneal meridian, and the most effective pattern is reverse arcuate type. In future holmium:YAG laser thermokeratoplasty might be clinically applicable as a operation of hyperopic astigmatism correction.

Retinal Detachment Associated with Probable Zonular Traction Tufts

Zonular traction tufts, which exist in 15% of normal population, do not cause retinal detachment by themselves but they can cause traction retinal detaehment when there is traction force added. It is thought that the possibility of development of retinal detaehment increases especially when zonular traetion tufts originate posterior to the vitreous base No case of traction retinal detachment caused by zonular traction tufts has been reported. Here, we report one suspected case of traction retinal detachment induced by zonular traction tufts and lens subluxation.

Posterior Capsule Opacification and Intraocular Lens Design in Sulcus Fixated Posterior Chamber Lens

Posterior capsule opacification(PCO) is a common complication of cataract surgery. The presence of a posterior chamber intraocular lens has been shown to decrease the incidence of the development of PCO. Moreover, there are evidences that the design of intraocular lens may also alter its development. Extracapsular lens extraction with implantation of posterior chamber lens were operated on a consecutive series of 230 eyes. These were evaluated in the viewpoint of PCO development after surgery. All were sulcus fixed and their optic designs were devided into two groups; a group of convex-plano lens with continuous laser ridge including convex-concave lens and a group of biconvex lens. The incidence of PCO was lower in convex-plano lens with continuous laser ridge group(6.7%) than that of boconvex lens group(18.9%). The incidence of Nd:YAG posterior capsulotomy marked 0.0% in continuous ridged group and 1.8% in biconvex group(p<0.05, p

The Study on the Role of NMDA Receptors in Rat Visual Cortex

The amino acid L-glutamate is a major excitatory neurotransmitter in central nervous system of vertebrates. NMDA( n-methyl-d-aspartate) is one of the L-glutamate receptor subtypes. During a critical period of early postnatal development, the visual cortex is susceptible to experience-dependent modification of neuronal response. Recently, the activation of NMDA receptors has been supposed as an prerequisite for the induction of such modification We therefore investigated developmental changes of NMDA receptors in rat visual cortex and questioned whether they could be related to the visual development. We assessed the density of [3H] NMDA receptor in visual cortex of normally reared rats (Group I) and visually deprivated rats (Group II) using quantitative autoradiography. The density of [3H] NMDA receptor was increased rapidly by postnatal 1 week and decreased after postnatal 5 weeks, and was significantly lower in Group II than Group I during early postnatal period. These results suggest that NMDA receptors may have a role in neuronal development in visual cortex.

A study on the role of N-methyl-D-aspartate receptors in the rat visual cortex

The amino acid L-glutamate is a major excitatory neurotransmitter in the central nervous system of vertebrates(1). NMDA (N-methyl-d-aspartate) is one of the L-glutamate receptor subtypes(2). During a critical period of early postnatal development, the visual cortex is susceptible to experience-dependent modification of neuronal responses. Recently, the activation of NMDA receptors has been supposed as a prerequisite for the induction of such modification(3). We therefore investigated developmental changes of NMDA receptors in the rat visual cortex and questioned whether they could be related to the visual development. We assessed the density of [(3)H]-NMDA receptor in the visual cortex of normally reared rate (Group I) and visually deprived rats (Group II) using quantitative autoradiography(4). The density of [(3)H]-NMDA receptor was significantly lower in Group II than in group I during the early postnatal period, and increased rapidly by postnatal 1 week and, decreased after postnatal 5 weeks. These results suggested that NMDA receptors may play a role in neuronal development in the visual cortex during the early postnatal period.

A Case of Bilateral Internuclear Ophthalmoplegia

Internuclear ophthalmoplegia(INO)is a horiwntal ocular motor disturbance caused by a lesion of the medial longitudinal fasciculus. We have experienced a case of bilateral internuclear ophthalmoplegia associated with exotropia, which revealed the symptom of bilateral impairment of adduction and dissociated nystagmus of the abducting eye on horizontal gaze in either direction. No bilateral internuclear ophthalmoplegia caused by trauma has yet been reported in this country. Here we report the case of the trauma-related medial longitudinal fasciculus lesion and its pathophysiology along with a literatural review.

A Case of Gronblad-Strandberg Syndrome with Subretinal Neovascularization

The authors experienced one case of Gronblad-Strandberg syndrome with subretinal neovascularization which showed characteristic signs of pseudoxanthoma elasticum(PXE) and angioid streak. PXE is an uncommon hereditary disorder which involves the elastic tissue of the dermis and may also involve the eye and the cardiovascular system. Angioid streaks are red or dark-brown jagged irregular lines extending in spoke like fashion toward periphery from an area of peripapillary atrophy. We report a case of Gronblad-Strandberg syndrome with subretinal neovasculari zation in a 49 year old korean female.

Extracapsular Cataract Extraction and Posteior Chamber IOL Implantation Using Ocutome-FragmatomeII System and Disposable Two-Way Needle

We tried extracapsular cataract extraction and PCL implantation with Ocutome-FragmatomeII System and Disposable Two-Way Needle. 160 eyes were operated with this method, 101 eyes were followed up over 2 months period. Clinical results were not significantly different from previous reports of ECCE and PCL implantaion. Corrected visual acuity 0.5 or better after 2 months of surgery were 95%. No serious intra-operative and post-operative complications were noted. We suggest Ocutome-FragmatomeII System and Disposble Two-Way Needle could be used for ECCE and PCL implantation in case of absence of I and A system.

Three Cases of Waardenburg's Syndrome in One Family

Warrdenburg's syndrome, a rare hereditary disease, may be transmitted as an irregular autosomal dominant traits, which is distinguished by lateral displacement of the medial canthi and inferior lacrimal puncta, broad and prominant nasal root, hyperplasia of the medial portions of the eye-brows, white or grey colored forelock, partial or total heterochromia of the irides, congenital deafness, etc. Recently, the authors have experienced three cases of Waardenburg's syndrome in one family. They were 29 year old male, his 4 year old son and 3 year old daughter. We report these interesting cases with a brief review of literatures.

Two Cases of Cavernous Hemangioma of the Palpebral Conjuntiva

Hemangioma appearing on the conjuntiva is a rare benign tumor which may be derived from vessels of conjuntiva, sclera, ocular muscles and orbit. Recently, we have experienced two cases of well encapsulated movable, round and slightly nodular conjuntival masses which had smooth, dark bluish-red colored surfaces. The masses were simply excised and histopathologic study revealed cavernous hemangioma.

A Case of Conjunctival Carcinoma in Situ

A 61-year-old korean male had noticed a growth on his left eye for the last 3 monthes. This had begun at the nasal limbus of his cornea and had spread over the surface of the cornea. The patient had undergone surgery for the removal of a "tumor on his stomach", about 3 years before, but, no further information concerning this was obtainable. The elevated mass was removed easily by simple excision, and the diagnosis was confirmed histopathologically as "conjunctival carcinoma in situ".