The Effect of RGP Lens and Reverse Geometry Lens on Redistribution of Corneal Epithelial Cell in Rabbit

PURPOSE: To investigate the migration and redistribution of rabbit corneal epithelial cells when wearing reverse geometry lens (RGL) or rigid gas permeable lens (RGP). METHODS: In 30 rabbits, the right eyes were fitted with either RGL or RGP and the left eyes were untreated to serve as controls. The rabbits were sacrificed at 1, 3, 7, 10 and 14 days after lens fitting. The central and peripheral corneal thicknesses were measured by microscope and the ratio of right to left corneal thickness was calculated to evaluate the characteristics of change over time. By using the molecular probe 7-nitrobenz-2-ox-1,3-diazolylphallacidin (NBD phallacidin), the samples were examined with light microscope to determine the migration and redistribution of epithelial cells in the rabbit cornea. RESULTS: No consistent changes in the thickness of both central and peripheral corneal epithelium were found. The corneal epithelial cells of both eyes with RGL and RGP reacted positively to NBD phallacidin. The fluorescence was most increased at day 3 of sacrifice in RGL cases and at day 7 in RGP cases, and then decreased in both cases. The corneal epithelium of eyes with RGL exhibited marked increase in the intensity of fluorescence compared to the eyes with RGP. CONCLUSIONS: The corneal epithelium with RGL showed the strongest intensity of NBD phallacidin fluorescence. This result suggests that wearing RGL may induce the migration and redistribution of corneal epithelial cells.

Quantitative Analysis of Retinal Nerve Fiber Layer Thickness Profile in Myopic Eyes

PURPOSE: To investigate peripapillary retinal nerve fiber layer (RNFL) thickness profiles associated with myopia. METHODS: One hundred and twenty-seven normal eyes of 67 Korean adults were divided into three groups by spherical equivalent. All subjects were tested with fast RNFL scans of Stratus optical coherence tomography. The angular locations of superior and inferior maximal thickness points in relationship to a reference line drawn horizontally though the center of the scan circle were calculated from the raw data of scanned images (angle alpha, angle beta). Differences of angle alpha and angle beta were compared among the three groups. RESULTS: Angle alpha and angle beta were significantly different in three groups (ANOVA, p<0.001, respectively). Angle alpha and angle beta were also significantly different among the three groups for excluded eyes with tilted discs. CONCLUSIONS: The points of superior and inferior maximal peripapillary RNFL thickness were significantly different in three groups divided by spherical equivalent. As myopia becomes more severe, superior and inferior maximal peripapillary RNFL thickness points are located closer to the fovea.

Thyroid Associated Orbitopathy following Periocular Surgery

PURPOSE: To descirbe a series of patients in which Thyroid Associated Orbitopathy (TAO) occurred after periocular surgery. METHODS: A retrospective case review of patients who developed TAO in close temporal association with periocular surgical interventions and presented at the orbital clinic from 1997 to 2004. History of previous thyroid abnormality and the lack of TAO signs and symptoms before surgery were reviewed and analyzed. RESULTS: Nine patients that developed TAO in association with periocular surgery were identified. All were women with an average age of 59.3years. (range: 45-75 years). The patients divided into two groups. Group 1 consisted of four patients who had previously been diagnosed with Graves' hyperthyroidism (GH). They ranged in age from 48 to 75 years (average: 58.8 years). The diagnosis of GH had been made an average of 50.5 months (range: 12-96 months) before presentation with TAO. Group 2 consisted of five patients who had no previous history of thyroid abnormality. They ranged in age from 45 to 74 years (average: 60.2 years). No patients had any signs or symptoms of TAO before their recent presentation. CONCLUSIONS: Periocular surgery may lead to local inflammatory events that may contribute to the instigation of TAO in predisposed individuals.

Changes in Refraction and Anterior Chamber Depth According to the Type of the Intraocular Lenses

PURPOSE: To evaluate the changes of refraction and anterior chamber depth in pseudophakia with the single-piece intraocular lenses (IOLs) and the three-piece IOLs after cataract surgery. METHODS: This single-center prospective study comprised of 34 eyes in 27 cataract patients who underwent cataract surgery. Eighteen eyes of seventeen patients received the single-piece IOLs, and sixteen eyes of fifteen patients received the three-piece IOLs. At one day, one week, and six months after cataract surgery, the refraction, corneal thickness, and anterior chamber depth of both groups were measured and analyzed. RESULTS: The refraction after cataract surgery was not significantly different from the preoperative predictive refraction in both IOL groups. The corneal thickness increased significantly as compared with preoperative value at operative day in both groups. However, after 1 week postoperatively, there was no statistically significant difference between the preoperative and the postoperative corneal thickness. The anterior chamber depth of the single-piece IOL group decreased constantly, and the decrease was statistically significant at 6 months postoperatively. In the three-piece group the anterior chamber depth was stationary and there was no statistically significant change from 1 day postoperatively. CONCLUSIONS: There was remarkable difference of the changes of anterior chamber depth after cataract surgery between the single-piece and the three-piece IOL groups. In particular, the relative decrease of anterior chamber depth of the single-piece IOL group would affect the postoperative refractive errors.

Cases of Complications after the Use of Punctal Plugs

PURPOSE: To report cases of complications after using punctual plugs with a literature review. METHODS: We studied 3 complicated cases after the use of punctual plugs: a 46-year-old female with recurrent mucopurulent discharge, a 42-year-old male with a pinkish mass over the punctum, and a 29-year-old female with recurrent epiphora. RESULTS: The 46-year-old female was diagnosed with canaliculitis caused by actinomyces, the 42-year-old male with chronic pyogenic granuloma, and the 29-year-old female with canalicular obstruction. All 3 cases improved after proper treatments. CONCLUSIONS: Complications after the use of punctal plugs are not common but they can be significant. They have to be used carefully after through evaluation and obtained proper informed consents from the patient.

Common Eye Diseases in the Primary Health Care

The eyes are the most important organ because they are directly related to a person's vision. Accordingly diseases of the eyes are of a great concern. Especially, corneal diseases, glaucoma, and retinal detachment require timely diagnosis and treatment. Recently age-related diseases tend to show an increasing trend with the increasing life expectancy in general. A significant proportion of patients with age-related macular degeneration and diabetic retinopathy end up with vision loss. Consequently, appropriate control of diabetes and regular ophthalmologic examinations are necessary. In addition, various external eye diseases caused by environmental pollution also show an increasing trend. Dry eye and conjunctivitis by bacteria, virus, various allergens, and air pollution are commonly encountered by primary health care providers. We hope this article will provide a quick and useful guide for the diagnosis and treatment of some of the most common eye diseases.

The Efficacy and Safety of Reverse Geometry Lenses

PURPOSE: To evaluate the amount of myopia correction and safety after Ortho-K LK(TM) lens wear. METHODS: We performed a retrospective analysis on 17 patients (34 eyes) wearing Ortho-K LK(TM) lenses. Uncorrected visual acuity, spherical equivalent, astigmatism, and corneal endothelial cell count were measured before fitting and 1week, 2weeks, and 1, 3 and 6months after lens fitting. RESULTS: There was significant improvement of uncorrected visual acuity and spherical equivalent 1week later and these effects maintained after 6months. However, there was no significant change of the amount of astigmatism and corneal endothelial cell density. The most common complications were decenterations of lenses, corneal erosion, and iron deposit.; these were not, however, serious enough to stop lens wearing. CONCLUSIONS: There was a significant improvement of unaided visual acuity and spherical equivalent after Ortho-K LK(TM) lens wear. There was some significant decrease of visual acuity between 3 and 6months after lens wear and there must be another reason other than patients' compliance.

Age and Spherical Equivalent Related Changes in Wavefront Aberrations

PURPOSE: To estimate the age and spherical equivalent related changes in the wavefront aberrations. METHODS: The age related difference in the wavefront aberrations were measured using a WASCA aberrometer on 63 eyes from 38 persons ranging in age from 18 to 60 years with a mean spherical equivalent of -0.55 diopter. The total RMS (root mean square), the high order RMS, coma and spherical aberration were analyzed and compared according to age(second, third, fourth, fifth and sixth decade). The spherical equivalent related difference in the wavefront aberrations were also measured on 118 eyes from 62 persons with a spherical equivalent ranging from +0.5 D to -10.5 D (average -4.87 D). The total RMS, high order RMS and spherical aberration were analyzed and compared according to the spherical equivalent. RESULTS: With increasing age, the total RMS showed no statistically significant increase (p>0.05), but a high order RMS and spherical aberration showed a significant increase (p0.05). With the increasing amount of spherical equivalent, the total RMS increased significantly (p0.05). CONCLUSIONS: In emmetropia, the total RMS and high order aberration increased significantly with increasing age. With increasing amount of spherical equivalent, the total RMS increased significantly while coma and the spherical aberrations did not.

Research on the Actual Educational Condition of Contact Lens in Korean Ophthalmology Residency Training Hospitals

PURPOSE: The purpose of this study is to determine the actual educational condition of contact lenses in Korean ophthalmology residency training hospitals. METHODS: A questionnaire survey about the educational condition of contact lenses was performed twice between October 2000 and September 2002 in 75 Korean ophthalmology residency training hospitals. In the second examination, the same primary questionnaire was administered to confirm the improvement of educational condition. RESULTS: Nine percent of the subjects were satisfied with the educational condition of contact lenses in the first examination and 12% in the second examination. Most residents were not satisfied because of lack of manpower and interest. The ratio of hospitals conducting the contact lens education program increased from 12% in the first examination to 45% in the second examination. Most of the residents agreed to alter the contact lenses fitting into obligatory provision during the residency training period; 80% in the first examination and 75% in the second examination. CONCLUSIONS: Most residents agreed with the necessity of contact lens education, but the program was not performed well. Thus, the interest and education of the Korea ophthalmologic society and each ophthalmology residency training hospital will be required to educate the information about contact lenses and their correct wearing.

Bilateral Episcleral Osseous Choristoma

PURPOSE: To report the symmetric masses developed in both eyes, which were diagnosed with bilateral osseous choristoma and surgically excised. METHODS: A 6-year-old female was noted by her parents to have a mass under the conjunctiva of her left eye. The mass was white and firmly attached to the globe. The same lesion was present in the right eye. CT scan showed that the masses were high bone-density and did not invade the sclera deeply. Therefore, excisional biopsy of the lesions were performed. RESULTS: Histopathologic examination showed that the masses were episcleral osseous choristoma. There was no complication of recurrence or adhesion after surgery. CONCLUSIONS: In case of a hard mass under the conjunctiva, which is diagnosed with osseous choristoma by CT scanning, it is helpful to determine the accurate location and adhesion of the massfor successful surgery.

Management with Radical Excision in Squamous Cell Carcinoma of the Lacrimal Sac

PURPOSE: Squamous cell carcinoma of the lacrimal sac is rare and there is high rate of recurrence after dacryocystectomy. We report successful radical excision of the tumor for the purpose of reducing the recurrence and improving the survival rate. METHODS: A 48-year-old man who had a history of epiphora and medial canthal mass for one year was referred to our clinic. CT scan showed a mass on the lacrimal fossa but there was no evidence of bony destruction or local invasion. We confirmed that the excised mass was squamous cell carcinoma of the lacrimal sac by frozen section. So, radical excision including bony and mucous nasolacrimal duct (NLD), inferior turbinate, and medial maxilla was performed through lateral rhinotomy. RESULTS: Ten months later, there was skin defect and medial canthal deformity. So we corrected the deformity with a forehead free flap and the result was cosmetically acceptable. There was no evidence of recurrence or distant metastasis for one- year follow- up period. CONCLUSIONS: Despite its high recurrence rate, we can reduce the recurrence and mortality rate of squamous cell carcinoma of the lacrimal sac with radical excision including bony and mucous NLD, inferior turbinate, and medial maxilla.

Research on the Current Status of Contact Lenses in Korea

PURPOSE: The purpose of this study is to present points of improvement data in developing a public educational approach for the correct understanding and use of contact lenses with a focus on the actual condition of wearing contact lenses, side effects and problem of circulation. METHODS: The questionnaires were distributed to contact lens wearers of 175 local clinics, 75 universities and general hospitals and 202 opticians were interviewed. RESULTS: This survey showed that many respondents had incorrect knowledge about contact lenses (purchase, prescription, complication, method of contact lens use), including persons who are not optometrists handling contact lenses. CONCLUSIONS: Nationwide pre-education is necessary for the correct understanding and purchase, prescription, and side effects of contact lenses, as well as to prohibit opticians from illegally prescribing the lenses; ophthalmologists should prescribe all contact lenses for proper vision correction.

A case of traumatic eyeball extrusion with complex, comminuted fractures

PURPOSE: Traumatic extrusion of the eyeball is rare. We experienced and successfully reconstructed a case of the eyeball extrusion with complete avulsion of the optic nerve, and complex, comminuted fractures of medial and inferior orbital walls. METHODS: A 27-year-old man presented with the ocular pain and eyeball extrusion of the right eye after the trauma. There were multiple lacerations of the eyelid and the conjunctiva of the right eye, the complete avulsion of the optic nerve and the avulsion of extraocular muscles except the lateral rectus muscle, and the eyeball extrusion of the right eye. We performed the enucleation with Medpor(R) sphere implantation and the reconstruction of the inferior and medial walls with Medpor(R) one channel and sheet implant. RESULTS: At one-year follow-up, there were no implant exposure and infection, and good cosmetic result was seen without enophthalmos. CONCLUSIONS: In a case of eyeball extrusion with complex, comminuted fractures after trauma, we could reconstruct these successfully with enucleation with Medpor(R) sphere implantation, and repair of fractures with Medpor(R) channel and sheet implant.

Normal Contrast Sensitivity for Various Ages

PURPOSE: To estimate the mean contrast sensitivity of normal Korean people and determine the difference between various ages. METHODS: One hundred sixty eight eyes with normal vision and no ocular disease were divided into three groups: the first group was ages between 10 and 19 years (n=32), the second group between 20 and 59 years (n=110), and the third group older than 60 years (n=26). We tested the contrast sensitivity with multivision contrast tester 8000 (Vistech Consultants, Inc., USA) which uses sine wave grating patches of 5 different spatial frequencies under standardized luminance at two different conditions of day and night RESULTS: Mean contrast sensitivities of total eyes at spatial frequencies of 1.5, 3, 6, and 18 cycles per degree were 40, 84, 92, 56, and 20 at day condition and 37, 70, 56, 21, and 5 at night condition, respectively. Mean contrast sensitivity of the first group was higher than that of others at all 5 spatial frequencies and there was no statistical significance between the second group and the third group (p<0.05). CONCLUSIONS: Mean contrast sensitivity of normal eyes included in this study was within the normal value of other previous study. There was statistically significant decrease of contrast sensitivity value in older age group.

Comparison of Wavefront Guided Customized Ablation vs. Conventional Ablation

PURPOSE: To compare the visual outcome and satisfaction rate after the wavefront guided ablation with the conventional ablation in laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) patients. METHODS: We performed a prospective study that included 182 eyes of 91 patients who were treated with LASIK (60 eyes) or PRK (122 eyes) using MEL 70 excimer laser system (Carl-Zeiss Meditec, Germany). We applied wavefront guided ablation on the right eye of each patient. The conventional ablation (control group) was performed on the left eye of the same patient. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), spherical equivalent refraction, high order aberrations and contrast sensitivity were evaluated preoperatively and after surgery. Satisfaction rate was evaluated after surgery. RESULTS: We found statistically insignificant improvement of BCVA in wavefront guided ablation group. There were no statistically significant differences in contrast sensitivity between wavefront guided ablation and conventional ablation. In LASIK group, we found statistically significant differences of high order aberrations; RMS HO (High order)(p<0.05) and in PRK group; Z (3, -1), Z (3, 3), Z (4, 0), Z (4, 2), RMS HO (p<0.05). There were no statistically significant differences between wavefront guided ablation and conventional ablation in patient's satisfaction. CONCLUSIONS: High order aberrations of wavefront guided ablation were less increased than of conventional ablation. These results indicate the potential role of the wavefront guided ablation in the field of refractive surgery.

Serratia Marcescens Keratitis

PURPOSE: Serratia marcescens keratitis is relatively common among the various bacterial corneal infections and has been known to be associated with contact lens wear. The authors performed a study to identify the risk factors, clinical features and treatment results. METHODS: Epidemiologic study was prospectively performed under the identical protocol from May 1995 to April 2000 in 11 hospitals. RESULTS: Twenty cases of Serratia marcescens keratitis were diagnosed. Contact lens wear was involved in Serratia marcescens keratitis in 90%. The highest age prevalence was in the thirties(45%). The majority of them were students(30%) and office workers(30%). CONCLUSIONS: The principle risk factor of Serratia marcescens keratitis in this study was contact lens wear. The proper use of contact lens and education on it's complications may play an important role in reducing the incidence rate of Serratia marcescens keratitis.

A Case of Acute Lymphoblastic Leukemia with Orbital Relapse

PURPOSE: Acute lympholastic leukemia is common in children but, rare in adults. Authors experienced a case of acute lympholastic leukemia with orbital relapse in adult, and we report this case with literature review. METHODS: A fifty-year-old woman complained of left eye pain and proptosis for 7 days. The superio-lateral subconjunctival mass excision and biopsy were performed and evisceration was done. The pathologic findings showed the lymphoblastic leukemia. Immunohistochemistry showed the original precursor T-lineage acute lymphoblastic leukemia. RESULTS: The mass was enlarged 40 days after surgery with pain, and subsided after radiation therapy. We recommended systemic chemotherapy, but she refused the therapy. She died 6months after surgery with systemic relapse.

Long-term Results of Laser in Situ Keratomileusis for High Myopia Above-15D

PURPOSE: We have evaluated the results of laser in situ keratomileuresis (LASIK) for high myopia above -15D over the follow-up periods of three years. METHODS: Twenty-two eyes from 15 LASIK patients were analyzed (10 eyes from 6 males and 12 eyes from 9 females). The average age was 30+/-6.7 years (20~42 years). The follow-up evaluations were performed at 6 months, 1 year and 3 years. RESULTS: The preoperative spherical equivalent ranged from -15.00D to -37.00D (average: -20.38+/-5.06D) and the mean postoperative spherical equivalents -2.07+/-3.43D at 6 months, -3.01+/-2.88D at 1 year, -3.05+/-2.86D at 3 years. Myopic regression continued during three-year follow-up, but, was not statistically significant (p>0.05). The incidence of increased BCVA 2 lines or more was 64% at 3 years and the case of decreased BCVA 2 lines or more was not found. The mean preoperative astigmatism was -2.93+/-2.11D and the mean postoperative astigmatisms were -0.81+/-0.81D at 6 months, -1.06+/-1.07D at 1 year and -1.16+/-1.44D at 3 years. It was significantly decreased (p<0.05). The intraoperative complications were not found. The postoperative complications after 3 years were myopic regression in 8 eyes, night glare in 8 eyes, decentration in 7 eyes and the foreign bodies in the border of the flap in 1 eye and there was no corneal haze. CONCLUSIONS: LASIK for high myopia above -15D is relatively safe. Howerver it needs further longterm evaluation.

Variation in Cataract Surgery Practice and Clinical Outcomes

PURPOSE: The purpose of this study was to examine the variations of the clinical outcomes of cataract surgery according to the characteristics of patients and surgeons and surgical technique. METHODS: The survey was conducted at 4 stages : preoperative period(389), perioperative period(344, 88.4%), postoperative 3~4 months(343, 88.2%), and postoperative 12 months(281, 72.2%). RESULTS: Eighty-five percent of surgery was performed by phacoemulsification and 14% by standard extracapsular (ECCE) techniques. The performance of phacoemulsification was associated with years of practice(11 years or more) and annual volume of cataract surgery(201 cases or more). The reported occurrence of posterior capsular opacification within 12 months of surgery was decreased in the patients operated by surgeons with years of practice(11 years or more). CONCLUSIONS: The factors influencing to better outcomes at 12 months after surgery were visual acuity of baseline operated eye(20/200 or less) and the absence of ocular morbidity. In this study, although there were some variations with cataract surgery practice, but the variations with cataract surgery practice did 434not give much influence to the patient's outcomes.

Differences in Keratocyte Apoptosis Between Laser and Mechanical Removal of Corneal Epithelium for PRK in Rabbits

PURPOSE: To evaluate the effects of different corneal epithelial manipulations in PRK procedure on keratocyte apoptosis. METHODS: Rabbit cornea was examined qualitatively and quantitatively after epithelial scraping(Group I), epithelial scraping followed by PRK(Group II) and transepithelial PRK(Group III). Each of them were compared with that of unwounded control. RESULTS: The number of anterior stromal keratocytes had decreased significantly and TUNEL-positive cells were significantly increased in the anterior stroma in group I and group II on POD 3 days compared with control group(p<0.05). There was a statistically significant increase in the number of anterior stromal keratocytes in group II compared with group III on POD 1 month(p<0.05). In group I and II, keratocytes that had morphologic changes consistent with apoptosis were detected with transmission and scanning electron microscopy on POD 3 days. But in group III, there were many normal appearing keratocyte in the anterior corneal stroma, and few keratocytes undergoing apoptosis. CONCLUSIONS: Transepithelial PRK induced lower levels of keratocyte apoptosis in rabbit cornea compared to those induced from epithelial scraping followed by PRK. This suggests that transepithelial PRK could be useful in preventing or minimizing refractive regression and corneal opacity, especially in cases of myopia or retreatment after regression.