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Purpose@#To analyze trends in corneal transplantation surgery and determine the number of domestic and imported corneal grafts used in South Korea.Method: The total number of keratoplasties and number of each individual surgical procedure conducted in 2010 and 2020 were identified using Health Insurance Review and Assessment Service data. The number of keratoplasties using domestic corneas in 2010 and 2020 was determined from the annual report of the Korean Network for Organ Sharing (KONOS). The number of keratoplasties using imported corneas was calculated by subtracting the number of keratoplasties using domestic corneas from the total number of keratoplasties. @*Results@#In 2010, 802 keratoplasties were performed in Korea, of which 299 (37.3%) used imported corneas; 715 (89.2%) were penetrating keratoplasties and 87 (10.8%) were anterior lamellar keratoplasties. In 2020, 911 keratoplasties were done in Korea and 564 (61.9%) used imported corneas; 541 (59.4%) were penetrating keratoplasties, 60 (6.6%) were anterior lamellar keratoplasties, and 310 (34.0%) were endothelial keratoplasties. From 2010 to 2020, the number of penetrating keratoplasties in Korea decreased, while the numbers of endothelial keratoplasties and keratoplasties using imported corneas increased. @*Conclusions@#There was a 30% decrease in the number of penetrating keratoplasties from 2010 to 2020, and a 30% increase in the numbers of endothelial keratoplasties and keratoplasties using imported corneas. The proportions of endothelial keratoplasties and imported corneas have increased steadily in Korea over the last 10 years.
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Purpose@#To compare the accuracy of modern intraocular lens (IOL) power calculation formulas in predicting refractive outcomes after standard cataract surgery. @*Methods@#The medical records of 203 eyes from 203 patients that received phacoemulsification and IOL implantation were retrospectively reviewed. Partial coherence interferometry was used to obtain the biometric values. The refractive outcomes of Barrett Universal II (BUII), Emmetropia Verifying Optical (EVO) 2.0, Hill-RBF 3.0, Hoffer QST, Kane, and PEARL-DGS formulas were evaluated. Axial length (AL) subgroup analysis was done separately. The correlations between the prediction error calculated by each formula and AL and corneal power were also analyzed. @*Results@#Overall, there was no significant difference between the absolute prediction errors predicted by the six formulas after adjusting the mean prediction error (p = 0.058). AL subgroup analysis of absolute error also showed that there is no significant difference between the formulas. The BUII and Hill-RBF 3.0 formulas showed a higher percentage of eyes with prediction error within ±0.50 diopters compared to the Hoffer QST formula (p = 0.022 and p = 0.035, respectively). However, there was no significant difference after Bonferroni correction was applied. The BUII formula showed the highest IOL Formula Performance Index and therefore the highest accuracy, followed by PEARL-DGS, EVO 2.0, Kane, Hill-RBF 3.0, and Hoffer QST formulas. Out of the six formulas, the prediction error calculated by the Hoffer QST was significantly correlated with the AL (p = 0.011). None of the prediction errors calculated by the six formulas showed correlation to the corneal power. @*Conclusions@#Analysis of the prediction error showed that the six modern IOL power calculation formulas have comparable accuracy overall and across different ranges of AL.
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Purpose@#To introduce an intuitive method for measuring conjunctival microvascular blood flow velocity by imaging bulbar conjunctival microvessels using a slit-lamp biomicroscope equipped with a zoom lens and an ultra-high-speed camera. @*Methods@#After obtaining consent from 10 patients (1 male, 9 females) who visited Yeouido St. Mary’s Hospital from August 21, 2020, to June 12, 2021, the patients were examined under a slit lamp microscope equipped with an ultra-high-speed camera and zoom lens. The blood flow in the conjunctival microvessels was photographed. The captured images were analyzed with ImageJ software to measure the blood flow velocity in the conjunctival microvessels, and we investigated whether the blood flow velocity correlated with the vessel diameter and age. @*Results@#The median age of the subjects was 49.0 years. The mean conjunctival blood flow velocity in 53 microvessels was 0.786 ± 0.468 mm/s. The median conjunctival microvascular diameter was 7.06 μm (interquartile range 5.84 to 9.23 μm). The conjunctival microvascular diameter and blood flow velocity were not significantly correlated (Spearman’s p = 0.177), and the subjects’ age and conjunctival microvascular blood flow velocity were also not correlated (Spearman’s p = 0.669). @*Conclusions@#In this study, the blood flow velocity in the bulbar conjunctival microvessels could be measured easily by means of image analysis using a slit-lamp microscope equipped with an ultra-high-speed camera with a zoom lens.
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Purpose@#To compare the degree of meibomian gland drop-out associated with Demodex infestation using non-contact meibography. @*Methods@#We performed noncontact meibography using an infrared digital camera on 24 adult subjects infested by Demodex and 40 without infestation. The right upper and lower lids were scored based on the loss of meibomian glands, and the scores of the upper and lower eyelids were summed to obtain the total meiboscore for each subject. Meiboscores were evaluated according to Demodex infestation and gender in each group. @*Results@#Sixty-four eyes of 64 people were enrolled in this study. The study subjects had an average age of 67.9 years (range, 40-79 years; men, 65.2 years; women, 69.1 years). There was a significant association between Demodex infestation and total meiboscore and upper and lower eyelid meiboscores (p = 0.000, p = 0.002, p = 0.004, respectively). There was no significant difference in the meiboscores between men and women. Age and meiboscore suggested a weak positive correlation; however, the R2 value was low, due to the concentrated age distribution of the study population. @*Conclusions@#Based on noncontact meibography, the authors concluded that the prevalence of changes in the meibomian glands was significantly related to Demodex infestation; however, there was no significant difference between men and women.
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Purpose@#Macular edema including cystoid macular edema is one of the main causes of unfavorable visual outcomes after cataract surgery. The macular thickness and the occurrence of macular edema after uncomplicated cataract surgery was evaluated using optical coherence tomography (OCT) in this study. @*Methods@#Macular map images were taken by OCT before surgery and at 1 week, 1 month, and 2 months postsurgery. The subjects were classified into two groups (group 1, patients with no macular edema; group 2, patients with macular edema). Group 2 was defined as increase in central macular thickness (CMT) by 30% compared with that before surgery. The risk factors for macular edema were evaluated. Group 2 was divided into two subgroups: subclinical macular edema (group 2A) and cystoid macular edema (group 2B) and they were assessed in terms of the clinical course of best-corrected visual acuity and CMT. @*Results@#A total of 376 patients were enrolled in this study, of which 36 (9.57%, group 2) showed macular edema measured by OCT after the surgery. Univariate analysis for group 1 and 2 revealed that intracameral injection of epinephrine during phacoemulsification was associated with the development of macular edema. In group 2, five patients (1.33%) developed cystoid macular edema. Statistically significant differences in the clinical course of CMT were observed at 2 months (201.2 ± 23.1, 250.0 ± 29.8, and 371.0 ± 160.3 in group 1, group 2A, and group 2B, respectively; p 0.2 with CMT in the normal range. @*Conclusions@#The intracameral injection of epinephrine may cause macular edema after uncomplicated cataract surgery. Examination of CMT using OCT is recommended for the early detection of macular edema.
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Purpose@#To compare the refractive measurements from a wavefront aberrometer, autorefractor, and retinoscopy after cycloplegia in evaluating the usefulness and validity of refractive measurements by a wavefront aberrometer in children. @*Methods@#A total of 130 eyes of 65 children, aged from 3 to 16 years, were examined using retinoscopy, a wavefront aberrometer (OPD-Scan III), and an autorefractor (KR-1) after cycloplegia. Refractive measurements were converted to power vectors (M, J0, and J45) and cylindrical absolute values for statistical analysis. The agreement between instruments was assessed and the correlations of measurements were evaluated. Subgroup analysis was performed on two subgroups: one representing less refractive error (|M| < 2 D on cycloplegic retinoscopy) and the other with larger refractive error (|M| ≥ 2 D on cycloplegic retinoscopy). @*Results@#Compared with retinoscopy readings, the aberrometer and autorefractor yielded more myopic values (p = 0.007, p < 0.001). In the less refractive error group, the autorefractor results showed statistically significant differences from retinoscopy readings for M, J0, and J45 and the cylindrical absolute value (all p < 0.05); there were no statistically significant differences between M, J0, and J45 vectors of the aberrometer and those obtained using retinoscopy (p = 0.674, p = 0.699, p = 0.766). With the larger refractive error group, the M vectors of the aberrometer and autorefractor showed more myopic values than the M vector retinoscopy readings; the differences were statistically significant (all p < 0.001). @*Conclusions@#The wavefront aberrometer yielded refraction readings closer to those obtained with retinoscopy than the automated refraction in the less refractive error group. With a larger refractive error, statistically significant differences (all p < 0.001) were found among the aberrometer, autorefractor, and retinoscopy readings.
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Purpose@#To report a case of secondary Descemet membrane endothelial keratoplasty (DMEK) for graft failure after primary DMEK.Case summary: A 47-year-old female underwent primary DMEK in her left eye with a diagnosis of Fuchs’ endothelial dystrophy. At 6 weeks later, corneal stromal edema with epithelial and subepithelial bullae was first observed. From that point on, the condition of the cornea and the visual acuity continued to degrade. After 7 months, a second DMEK procedure (i.e., a repeat DMEK) for graft failure was performed successfully without any complications. Since the second procedure, the cornea has been clear, and the best-corrected visual acuity has remained at 0.6 for 8 months. @*Conclusions@#To manage graft failure after primary DMEK, we performed a second DMEK procedure. The removal of the previous graft was easy, and there were no complications. Thus, repeat DMEK may be a feasible procedure.
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Purpose@#We derived optimal formulae permitting effective lens position (ELP) for patients differing in terms of their preoperative axial lengths as revealed by partial coherence interferometry. @*Methods@#We included 736 eyes from 736 patients who underwent conventional cataract surgery at Yeouido St. Mary’s Hospital. The preoperative axial length (AL), corneal power (CP), and anterior chamber depth (ACD) measured via partial coherence interferometry served as independent variables for ELP prediction. The 736 eyes were divided into seven groups differing by 1.0-mm intervals in terms of the preoperative axial length. We sought correlations between the independent variables and the ELP, and defined the combinations that best predicted the ELPs of the seven groups. @*Results@#The CP correlated significantly with the ELP for eyes with AL between 22.0 and 25.0 mm (all p < 0.01) and the ACD correlated significantly with the ELP for eyes with AL between 23.0 and 26.0 mm (all p < 0.01). Although a regression equation featuring all of the AL, ACD, and CP best predicted the ELP for the total of 736 eyes (p < 0.001), the optimal combination varied by the preoperative AL. @*Conclusions@#The effects of CP, ACD, and AL on ELP vary by the preoperative AL. The optimal combination of preoperative variables predicting ELP thus varies as that parameter changes.
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Purpose@#To report a case of Descemet stripping automated endothelial keratoplasty (DSAEK) for graft failure after re-penetrating keratoplasty (PK).Case summary: A 33-year-old man of Indian nationality who had developed right eye amoeba keratitis and had received two penetrating keratoplasties and allogeneic kerato-limbal transplant in India sought treatment at our hospital. During the follow-up, Ahmed valve transplantation was performed under the diagnosis of secondary glaucoma in his right eye; the patient also underwent conjunctival recession and conjunctival permanent amniotic membrane transplantation as corneal neovascularization had progressed. Subsequently, the corneal transplantation failed and DSAEK was performed. At 7 months after the operation, the right-eye visual acuity was 20/320 without any complications. @*Conclusions@#DSAEK may restore good vision without complications in patients with repeated corneal graft failure after PK from corneal endothelial cell failure followed by corneal neovascularization and glaucoma surgery but with good stromal conditions. We present this case, along with a review of the literature. Future studies will require more surgical patients.
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Purpose@#To report a case of a successful secondary Descemet membrane endothelial keratoplasty in failed penetrating keratoplasty. Case summary: A 46-year-old male with keratoconus in both of his eyes underwent penetrating keratoplasty in his right eye 30 years ago and in his left eye 14 years ago. From one and a half year ago, the patient’s visual acuity decreased in his left eye due to graft failure. For treatment, secondary Descemet membrane endothelial keratoplasty was performed. Partial detachment of Descemet membrane was observed at 13 days after the operation, and an additional air injection was performed. At 8 months after the operation, the patient’s uncorrected visual acuity improved to 0.5 and the cornea maintained its clearance without rejection. @*Conclusions@#Secondary Descemet membrane endothelial keratoplasty was successfully performed in a patient with failed penetrating keratoplasty.
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Purpose@#To compare the refractive measurements from a wavefront aberrometer, autorefractor, and retinoscopy after cycloplegia in evaluating the usefulness and validity of refractive measurements by a wavefront aberrometer in children. @*Methods@#A total of 130 eyes of 65 children, aged from 3 to 16 years, were examined using retinoscopy, a wavefront aberrometer (OPD-Scan III), and an autorefractor (KR-1) after cycloplegia. Refractive measurements were converted to power vectors (M, J0, and J45) and cylindrical absolute values for statistical analysis. The agreement between instruments was assessed and the correlations of measurements were evaluated. Subgroup analysis was performed on two subgroups: one representing less refractive error (|M| < 2 D on cycloplegic retinoscopy) and the other with larger refractive error (|M| ≥ 2 D on cycloplegic retinoscopy). @*Results@#Compared with retinoscopy readings, the aberrometer and autorefractor yielded more myopic values (p = 0.007, p < 0.001). In the less refractive error group, the autorefractor results showed statistically significant differences from retinoscopy readings for M, J0, and J45 and the cylindrical absolute value (all p < 0.05); there were no statistically significant differences between M, J0, and J45 vectors of the aberrometer and those obtained using retinoscopy (p = 0.674, p = 0.699, p = 0.766). With the larger refractive error group, the M vectors of the aberrometer and autorefractor showed more myopic values than the M vector retinoscopy readings; the differences were statistically significant (all p < 0.001). @*Conclusions@#The wavefront aberrometer yielded refraction readings closer to those obtained with retinoscopy than the automated refraction in the less refractive error group. With a larger refractive error, statistically significant differences (all p < 0.001) were found among the aberrometer, autorefractor, and retinoscopy readings.
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Purpose@#To report a case of secondary Descemet membrane endothelial keratoplasty (DMEK) for graft failure after primary DMEK.Case summary: A 47-year-old female underwent primary DMEK in her left eye with a diagnosis of Fuchs’ endothelial dystrophy. At 6 weeks later, corneal stromal edema with epithelial and subepithelial bullae was first observed. From that point on, the condition of the cornea and the visual acuity continued to degrade. After 7 months, a second DMEK procedure (i.e., a repeat DMEK) for graft failure was performed successfully without any complications. Since the second procedure, the cornea has been clear, and the best-corrected visual acuity has remained at 0.6 for 8 months. @*Conclusions@#To manage graft failure after primary DMEK, we performed a second DMEK procedure. The removal of the previous graft was easy, and there were no complications. Thus, repeat DMEK may be a feasible procedure.
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Purpose@#We derived optimal formulae permitting effective lens position (ELP) for patients differing in terms of their preoperative axial lengths as revealed by partial coherence interferometry. @*Methods@#We included 736 eyes from 736 patients who underwent conventional cataract surgery at Yeouido St. Mary’s Hospital. The preoperative axial length (AL), corneal power (CP), and anterior chamber depth (ACD) measured via partial coherence interferometry served as independent variables for ELP prediction. The 736 eyes were divided into seven groups differing by 1.0-mm intervals in terms of the preoperative axial length. We sought correlations between the independent variables and the ELP, and defined the combinations that best predicted the ELPs of the seven groups. @*Results@#The CP correlated significantly with the ELP for eyes with AL between 22.0 and 25.0 mm (all p < 0.01) and the ACD correlated significantly with the ELP for eyes with AL between 23.0 and 26.0 mm (all p < 0.01). Although a regression equation featuring all of the AL, ACD, and CP best predicted the ELP for the total of 736 eyes (p < 0.001), the optimal combination varied by the preoperative AL. @*Conclusions@#The effects of CP, ACD, and AL on ELP vary by the preoperative AL. The optimal combination of preoperative variables predicting ELP thus varies as that parameter changes.
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Purpose@#To report a case of Descemet stripping automated endothelial keratoplasty (DSAEK) for graft failure after re-penetrating keratoplasty (PK).Case summary: A 33-year-old man of Indian nationality who had developed right eye amoeba keratitis and had received two penetrating keratoplasties and allogeneic kerato-limbal transplant in India sought treatment at our hospital. During the follow-up, Ahmed valve transplantation was performed under the diagnosis of secondary glaucoma in his right eye; the patient also underwent conjunctival recession and conjunctival permanent amniotic membrane transplantation as corneal neovascularization had progressed. Subsequently, the corneal transplantation failed and DSAEK was performed. At 7 months after the operation, the right-eye visual acuity was 20/320 without any complications. @*Conclusions@#DSAEK may restore good vision without complications in patients with repeated corneal graft failure after PK from corneal endothelial cell failure followed by corneal neovascularization and glaucoma surgery but with good stromal conditions. We present this case, along with a review of the literature. Future studies will require more surgical patients.
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Purpose@#To report a case of a successful secondary Descemet membrane endothelial keratoplasty in failed penetrating keratoplasty. Case summary: A 46-year-old male with keratoconus in both of his eyes underwent penetrating keratoplasty in his right eye 30 years ago and in his left eye 14 years ago. From one and a half year ago, the patient’s visual acuity decreased in his left eye due to graft failure. For treatment, secondary Descemet membrane endothelial keratoplasty was performed. Partial detachment of Descemet membrane was observed at 13 days after the operation, and an additional air injection was performed. At 8 months after the operation, the patient’s uncorrected visual acuity improved to 0.5 and the cornea maintained its clearance without rejection. @*Conclusions@#Secondary Descemet membrane endothelial keratoplasty was successfully performed in a patient with failed penetrating keratoplasty.
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Purpose@#We report a case of secondary Descemet membrane endothelial keratoplasty (DMEK) to treat graft failure after Descemet stripping endothelial keratoplasty (DSEK).Case summary: A 66-year-old female underwent DSEK of her right eye to treat pseudophakic bullous keratopathy that developed after cataract surgery and intraocular lens exchange. After 5 years, she complained of decreased vision; graft failure was observed. Secondary DMEK was performed; no additional air injection was needed. The corrected visual acuity was 0.2, 3 months after surgery, and the cornea became clear. @*Conclusions@#Visual recovery can be achieved by performing secondary DMEK after primary DSEK graft failure.
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Purpose@#We report a case of secondary Descemet membrane endothelial keratoplasty (DMEK) to treat graft failure after Descemet stripping endothelial keratoplasty (DSEK).Case summary: A 66-year-old female underwent DSEK of her right eye to treat pseudophakic bullous keratopathy that developed after cataract surgery and intraocular lens exchange. After 5 years, she complained of decreased vision; graft failure was observed. Secondary DMEK was performed; no additional air injection was needed. The corrected visual acuity was 0.2, 3 months after surgery, and the cornea became clear. @*Conclusions@#Visual recovery can be achieved by performing secondary DMEK after primary DSEK graft failure.
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PURPOSE: To compare the efficacy and complications of scleral fixation of posterior chamber intraocular lens (IOL) and retropupillary fixation of iris claw IOL for dislocated IOL or aphakia without sufficient capsular support. METHODS: This retrospective study was comprised of 17 eyes of 16 patients undergoing scleral fixation and 14 eyes of 13 patients undergoing retropupillary fixation from August 2013 to June 2018. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), intraocular pressure (IOP), slit lamp examination, corneal topography, refractive indices, corneal curvatures, corneal endothelial cell density, and complications of both groups were examined preoperatively and 1 day, 1 week, 1 month, 2 months, and 6 months postoperatively. RESULTS: Six months after the operation, UCVA and BCVA improved in both groups; however, there were no significant differences between the two groups (UCVA, p = 0.162; BCVA, p = 0.418). IOP was temporarily higher in the scleral fixation group at one day postoperatively (p = 0.023). The mean absolute prediction error was smaller in the retropupillary iris fixation group at 6 months postoperatively (p = 0.034). Postoperative total astigmatism, corneal astigmatism, and corneal endothelial cell density were not significantly different between the two groups. CONCLUSIONS: The retropupillary iris fixation group did not show significant improvement in visual acuity compared with the scleral fixation group. However, the retropupillary iris fixation group provided better mean absolute prediction error and a low risk of postoperative increase in IOP compared with the scleral fixation group. Retropupillary fixation of iris claw IOL is a promising option for scleral fixation of posterior chamber IOL for dislocated IOL or aphakia without sufficient capsular support.
Subject(s)
Animals , Humans , Aphakia , Astigmatism , Corneal Topography , Endothelial Cells , Hoof and Claw , Intraocular Pressure , Iris , Lenses, Intraocular , Refractometry , Retrospective Studies , Slit Lamp , Visual AcuityABSTRACT
PURPOSE: We report the clinical manifestations of dry eye syndrome after cataract surgery involving meibomian gland structure, meibomian gland function, and tear lipid layer analysis. METHODS: The clinical manifestations of dry eye syndrome were retrospectively evaluated in 34 eyes of 31 patients who underwent cataract surgery from September to November 2017. The ocular surface disease index (OSDI), tear break-up time (tBUT), Oxford stain score, presence or absence of blepharitis, and meibomian gland expression were measured preoperatively and at 1 week, 1 month, and 2 months postoperatively. Lipid layer thickness (LLT), partial blinks, and meibomian gland images were measured using LipiView® (TearScience, Morrisville, NC, USA), an interferometric eye surface measuring device. RESULTS: The postoperative OSDI was significantly higher than preoperative OSDI (17.09 ± 1.81): 22.76 ± 1.99 at 1 week, 23.12 ± 1.91 at 1 month, and 22.68 ± 1.92 at 2 months (p < 0.05). The postoperative tBUT was significantly lower than preoperative tBUT (5.07 ± 0.39): 3.99 ± 0.31 at 1 week, 3.49 ± 0.27 at 1 month, and 4.72 ± 0.39 at 2 months (p < 0.05). The Oxford staining score increased after surgery, but the difference was not statistically significant. Postoperative meibomian gland expression was significantly lower preoperative values (4.9 ± 2.8): 4.4 ± 2.8 at 1 month, and 3.9 ± 2.8 at 2 months (p < 0.05). The LLT decreased at 1 month postoperatively and increased at 2 months postoperatively, but these differences were not statistically significant. CONCLUSIONS: Cataract surgery resulted in a short-term meibomian gland dysfunction, leading to deterioration of dry eye after cataract surgery. However, we could not confirm structural changes in the meibomian gland, so it will be necessary to observe the clinical features of dry eye syndrome over a longer period of time.
Subject(s)
Humans , Blepharitis , Cataract , Dry Eye Syndromes , Meibomian Glands , Retrospective Studies , TearsABSTRACT
PURPOSE: To analyze the length and area of limbal dermoid invading the cornea and to evaluate the effects on visual acuity and astigmatism before and after surgery. METHODS: This retrospective study included 20 eyes of 20 patients who underwent surgical removal of limbal dermoid. The preoperative and postoperative visual acuity and astigmatism level were measured. In addition, we evaluated the correlations of astigmatism with the length ratio (length of limbal dermoid invading the cornea/total corneal diameter), width ratio (width of limbal dermoid invading the cornea/total corneal diameter), and area ratio (area of limbal dermoid invading the cornea/total corneal area) using preoperative anterior segment photographs. RESULTS: The mean preoperative astigmatism was 0.85 ± 0.71 D in the sound eye and 3.00 ± 3.14 D in the affected eye (p = 0.004). Length, width, and area ratio of limbal dermoid have positive correlation with astigmatism (p < 0.010 for all variables), with a larger length ratio of limbal dermoid invading the cornea producing greater reduction in postoperative astigmatism (p = 0.010, r = 0.816). The amount of astigmatism was significantly higher in patients with amblyopia in the affected eye (p = 0.030). Visual acuity gain more than 2 lines was achieved in 8 among 10 patients with amblyopia under the age of 7 years through the appropriate refractive correction and occlusion 1 year after surgery. CONCLUSIONS: Astigmatism is a major cause of amblyopia in pediatric patients with limbal dermoid. The degree of astigmatism can be predicted by the size factors of the limbal dermoid. In particular, the relative length of limbal dermoid invading the cornea has a stronger correlation with preoperative astigmatism than other factors and has correlation with postoperative reduction of astigmatism. It should be emphasized that children with limbal dermoid need appropriate refractive correction and occlusion in addition to surgical excision.