Rigid gas permeable (RGP) contact lenses are made of materials with excellent oxygen permeability and wettability, so they not only improve oxygen permeability compared to existing lenses, but also provide correction of refractive errors and improved vision in irregular corneas such as keratoconus. However, the hard material of the lens along with hypoxia and hypercapnia of the cornea caused by wearing RGP contact lenses cause various physiological changes in the cornea. Physiological changes in the cornea that may occur when wearing RGP contact lenses include mucin balls, decreased corneal epithelial thickness and increased size, decreased epithelial barrier function, corneal erosion and staining, decreased keratocyte density, decreased corneal sensitivity, and stromal opacities, contact lens‐induced peripheral ulcers, endothelial blebs, increased endothelial polymegethism, and changes in corneal shape. It is necessary to know the performance of the RGP contact lenses being prescribed, be aware of the physiological changes in the cornea caused by wearing RGP contact lenses, and provide the correct lens prescription along with appropriate education to the patient.

PURPOSE: To investigate systemic factors associated with central serous chorioretinopathy (CSC). METHODS: We retrospectively reviewed the medical records of 113 Korean patients who were diagnosed with CSC and who underwent history taking with a specialized questionnaire for CSC. They were matched for age and gender at a ratio of 1 : 3 to 339 normal controls. Normal controls were consecutively selected from a database at the Health Promotion Center. General characteristics and medical histories were compared between the two groups. The statistical analyses used included independent t-test, Mann-Whitney test, Fisher's exact test, and multivariate logistic regression analysis. RESULTS: There were 90 men and 23 women in the CSC group, and the male-female ratio for both groups was 3.9 : 1. The mean age of the patients was 45.6 years. In multivariate analysis, hypertension (odds ratio [OR], 2.327; 95% confidence interval [CI], 1.349-4.013), use of medicinal plants (OR, 2.198; 95% CI, 1.193-4.049), sleep disturbances (OR, 1.732; 95% CI, 1.096-2.739), and snoring (OR, 1.727; 95% CI, 1.058-2.820) were strongly associated with CSC. CONCLUSIONS: Hypertension, sleep disturbance, snoring, and medicinal plant use were identified as factors associated with CSC. Expanded history taking, including systemic factors and culture-specific behavior related to stress or fatigue such as use of medicinal plants, will be helpful in identifying Korean patients at an increased risk for CSC.
Asian Continental Ancestry Group ; Case-Control Studies ; Central Serous Chorioretinopathy/*epidemiology/*etiology ; Female ; Humans ; Logistic Models ; Male ; Middle Aged ; Questionnaires ; Republic of Korea/epidemiology ; Retrospective Studies ; Risk Factors ; Statistics, Nonparametric

PURPOSE: To investigate the effects of cataract grade based on wide-field fundus imaging on macular thickness measured by spectral domain optical coherence tomography (SD-OCT) and its signal-to-noise ratio (SNR). METHODS: Two hundred cataract patients (200 eyes) with preoperative measurements by wide-field fundus imaging and macular SD-OCT were enrolled. Cataract severity was graded from 1 to 4 according to the degree of macular obscuring by cataract artifact in fundus photo images. Cataract grade based on wide-field fundus image, the Lens Opacity Classification System III, macular thickness, and SD-OCT SNR were compared. All SD-OCT B-scan images were evaluated to detect errors in retinal layer segmentation. RESULTS: Cataract grade based on wide-field fundus imaging was positively correlated with grade of posterior subcapsular cataracts (rho = 0.486, p < 0.001), but not with nuclear opalescence or cortical cataract using the Lens Opacity Classification System III. Cataract grade was negatively correlated with total macular thickness (rho = −0.509, p < 0.001) and SD-OCT SNR (rho = −0.568, p < 0.001). SD-OCT SNR was positively correlated with total macular thickness (rho = 0.571, p < 0.001). Of 200 eyes, 97 (48.5%) had segmentation errors on SD-OCT. As cataract grade increased and SD-OCT SNR decreased, the percentage of eyes with segmentation errors on SD-OCT increased. All measurements of macular thickness in eyes without segmentation errors were significantly greater than those of eyes with segmentation errors. CONCLUSIONS: Posterior subcapsular cataracts had profound effects on cataract grade based on wide-field fundus imaging. As cataract grade based on wide-field fundus image increased, macular thickness tended to be underestimated due to segmentation errors in SD-OCT images. Segmentation errors in SD-OCT should be considered when evaluating macular thickness in eyes with cataracts.
Artifacts ; Cataract* ; Classification ; Fundus Oculi ; Humans ; Iridescence ; Retinaldehyde ; Signal-To-Noise Ratio ; Tomography, Optical Coherence

PURPOSE: To compare the effect of posterior corneal astigmatism on the estimation of total corneal astigmatism using anterior corneal measurements (simulated keratometry [K]) between eyes with keratoconus and healthy eyes. METHODS: Thirty-three eyes of 33 patients with keratoconus of grade I or II and 33 eyes of 33 age- and sex-matched healthy control subjects were enrolled. Anterior, posterior, and total corneal cylinder powers and flat meridians measured by a single Scheimpflug camera were analyzed. The difference in corneal astigmatism between the simulated K and total cornea was evaluated. RESULTS: The mean anterior, posterior, and total corneal cylinder powers of the keratoconus group (4.37 ± 1.73, 0.95 ± 0.39, and 4.36 ± 1.74 cylinder diopters [CD], respectively) were significantly greater than those of the control group (1.10 ± 0.68, 0.39 ± 0.18, and 0.97 ± 0.63 CD, respectively). The cylinder power difference between the simulated K and total cornea was positively correlated with the posterior corneal cylinder power and negatively correlated with the absolute flat meridian difference between the simulated K and total cornea in both groups. The mean magnitude of the vector difference between the astigmatism of the simulated K and total cornea of the keratoconus group (0.67 ± 0.67 CD) was significantly larger than that of the control group (0.28 ± 0.12 CD). CONCLUSIONS: Eyes with keratoconus had greater estimation errors of total corneal astigmatism based on anterior corneal measurement than did healthy eyes. Posterior corneal surface measurement should be more emphasized to determine the total corneal astigmatism in eyes with keratoconus.
Astigmatism* ; Cornea ; Humans ; Keratoconus* ; Meridians

Purpose: We used anterior segment optical coherence tomography (AS-OCT) to measure the pterygial subepithelial invasion length and thickness before and after surgery, and to evaluate the corneal epithelium and the extent of astigmatism. Methods: This was a retrospective study. Ten eyes that underwent pterygial excision surgery were analyzed. We used corneal topographic data to assess astigmatism before surgery and employed AS-OCT to measure corneal epithelial thickness and the length of subepithelial invasion. We measured the relative pterygial length, width, and area on anterior segment photographs. Corneal topographic assessment and AS-OCT were repeated 1 month after surgery. Multiple regression and Pearson correlation analyses were used to analyze the relationships between normalization of astigmatism and the size and thickness of the excised pterygium. Results: The mean With-the-Rule proportion of preoperative astigmatism was 2.9 ± 2.3 D and the mean corneal epithelial thickness 269.60 ± 84.17 µm. The mean thickness of the excised pterygia was 210.73 ± 80.36 µm. Pterygial thickness was significantly associated with the extent of preoperative With-the-Rule astigmatism and the normalized With-the-Rule astigmatism after pterygial excision. These correlations were stronger than those of the relative pterygial length, width, and area. The mean subepithelial invasion length was 595.00 ± 310.32 µm. Conclusions An increase in pterygial epithelial thickness influenced the extent of With-the-Rule astigmatism to a much greater extent than did the relative pterygial length, width, and area. AS-OCT measurement of the subepithelial invasion length identifies the required excisional area prior to surgery.

Purpose: We compared the cataract grades with slit lamp examination and anterior segment photography using the Lens Opacities Classification System (LOCS) III criteria. We also explored the effect of a yellow filter on the photographic results. Methods: Eighty eyes with cataracts were examined by three inspectors (1, 2, and 3). Anterior segment photographs taken by inspector 1 were divided into two groups depending on whether cortical opacity or nuclear sclerosis predominated. In each group, the cataract grades determined by inspector 1 on slit lamp examination and anterior segment photography were compared. Also, after randomly assigning the anterior segment photographs taken by inspector 1 to inspectors 2 and 3, the cataract grades of these photographs were compared to the grades of photographs taken by all inspectors using a yellow filter. Results: The average cortical opacity evaluated by inspector 1 on slit lamp examination (3.48 ± 0.91) was significantly higher than that apparent on anterior segment photographs (2.35 ± 0.77) (p < 0.001). In the photographs, the average cortical opacity when a yellow filter was used was significantly higher for both inspectors 1 (p < 0.001) and 2 (p = 0.022) than when the filter was absent. The average extent of nuclear sclerosis evaluated by inspector 1 on slit lamp examination (4.08 ± 0.94) was significantly higher than that of anterior segment photography (3.73 ± 1.24) (p = 0.042). Conclusions Cataract evaluation via anterior segment photography underestimates the extent of damage compared to direct slit lamp examination. However, use of a yellow filter during photography aids cataract evaluation, especially cortical opacity.

This case report describes a case of self-inflicted chronic bacterial keratoconjunctivitis involving the patient's own semen. A 20-year-old male soldier was referred to our clinic for the evaluation of refractory chronic bacterial conjunctivitis. Over the previous 4 months, he had been treated for copious mucous discharge, conjunctival injection, and superficial punctate keratitis in both eyes at an army hospital and a local eye clinic. Despite the use of topical and systemic antibiotics according to the results of conjunctival swab culture, there was no improvement. During the repeated smear and culture of conjunctival swabs, surprisingly, a few sperm were detected on Gram staining, revealing that the condition was self-inflicted bacterial keratoconjunctivitis involving the patient's own semen. Thus, in cases of chronic keratoconjunctivitis that do not respond to appropriate antibiotic treatment, self-inflicted disease or malingering should be considered.
Chronic Disease ; Conjunctiva/*injuries/microbiology/pathology ; Cornea/microbiology/*pathology ; Diagnosis, Differential ; Eye Infections, Bacterial/diagnosis/*etiology/microbiology ; Eye Injuries/*complications/diagnosis ; Humans ; Keratoconjunctivitis/diagnosis/*etiology/microbiology ; Male ; Self Mutilation/*complications/diagnosis ; *Semen ; Young Adult

PURPOSE: To investigate cataract surgical experiences during ophthalmology residency in Korea. METHODS: A survey regarding cataract surgical experiences during residency was sent to 4th year ophthalmologic residents (112) from April to September 2010. RESULTS: Of the 112 individuals to whom the surveys were sent, 35 (31.3%) responded. The majority of the respondents (65.7%) performed their first cataract operation as the primary surgeon in their 4th year of residency. The majority of the respondents (42.9%) also thought that continuous curvilinear capsulorhexis (CCC) was the most difficult procedure followed by nucleus removal (31.4%). Fourteen respondents (40.0%) experienced loss of lens fragments into the vitreous cavity. Nine (25.7%) respondents had experienced performing ECCE (Extracapsular cataract extraction) during residency training. Also, 48.6% performed 1 to 5 cataract procedures during their entire residency training while 20.0% performed 6 to 10. CONCLUSIONS: The experiences in cataract surgery during residency were investigated for the first time through a questionnaire survey. The Korean ophthalmology residency program needs to provide more opportunities for residents to perform cataract surgery during their training period.
Capsulorhexis ; Cataract ; Surveys and Questionnaires ; Internship and Residency ; Korea ; Ophthalmology

PURPOSE: To validate the possibility of IOLMaster measurement as a predictor of intraoperative and postoperative complications during phacoemulsification surgery. METHODS: In this study, 2,107 eyes from 1,456 patients who underwent phacoemulsification with intraocular lens (IOL) implantation were divided into two groups according to the possibility of performing optical biometry with the IOLMaster (measurable group: 1,746 eyes from 1,141 patients, unmeasurable group: 361 eyes from 315 patients). The intraoperative and postoperative complication rates were compared between the two groups. RESULTS: Three hundred sixty-one eyes (17.1%) could not be measured using optical biometry. Dense posterior subcapsular cataract (56.0%) was the main factor resulting in failed measurements with optical biometry, followed by anterior subcapsular cataract (12.5%). The rates of posterior capsule rupture and radial tear were significantly higher in the unmeasurable group than in the measurable group (p = 0.001, p < 0.001, respectively). Corneal edema was significantly higher in the unmeasurable group (16.1%) than in the measurable group (5.3%) at postoperative 1 week (p < 0.001). CONCLUSIONS: Possibility of optical biometry measurement can be used as a simple predictor of intraoperative and postoperative complications of phacoemulsification surgery. Surgeons should pay close attention to patients who cannot be measured using IOLMaster.
Biometry ; Cataract* ; Corneal Edema ; Humans ; Incidence* ; Interferometry* ; Lenses, Intraocular ; Phacoemulsification ; Postoperative Complications ; Rupture ; Surgeons ; Tears

PURPOSE: To evaluate the long-term changes in cornea endothelial cell density (ECD) after pars plana vitrectomy (PPV) with fragmentation. METHODS: Twenty patients (20 eyes) who underwent PPV with fragmentation and who were followed up for 2 years were enrolled in this retrospective study. The cornea ECD, coefficient of variation (CV), and hexagonality (HA) were calculated using a specular microscopy at 1, 3, 6, 12 months, and 2 years after surgery. RESULTS: The preoperative mean ECD was 1,782 ± 623 cells/mm², and the postoperative mean ECD did not significantly change at 1, 3, 6, and 12 months. Additionally, there were no significant changes in CV or HA. At 2 years after surgery, the mean ECD was 1,722 ± 532 cells/mm², the mean CV was 35.50 ± 3.03%, and the mean HA was 53.00 ± 4.91%. There were no significant changes in ECD, CV, or HA preoperatively and postoperatively at 1, 3, 6, and 12 months. CONCLUSIONS: In this study, the mean ECD did not significantly decrease after PPV with fragmentation at 2 years after surgery. A PPV with fragmentation was an appropriate surgical procedure for patients with low cornea endothelial cell density.
Cornea ; Endothelial Cells* ; Humans ; Microscopy ; Retrospective Studies ; Vitrectomy*