Comparison of choroidal structural changes between children born preterm without retinopathy of prematurity and age-matched children born at full term.

AIM: To evaluate the effect of prematurity on choroidal structure in children born preterm with no history of retinopathy of prematurity (ROP) by comparing them with age-matched healthy children born at full term. METHODS: Enhanced depth imaging optical coherence tomography (EDI-OCT) scans of children aged 5 to 9 years with a history of prematurity but no history of ROP, and age-matched full-term healthy children were evaluated, retrospectively. Choroidal thicknesses (CTs) were measured at subfoveal (SFCT), 1000 µm temporal and nasal from the fovea (T1, N1), and 2000 µm temporal and nasal (T2, N2) from the fovea. The EDI-OCT images were binarized to stromal (SA) and luminal areas (LA) using the ImageJ software. The choroidal vascularity index (CVI) was calculated by dividing LA by the total choroidal area (TCA). RESULTS: Twenty-nine eyes of 15 preterm children and 41 eyes of 26 full-term children were included. Demographic characteristics including axial length (AL), eye side, age, and the sex of the children in the groups were similar (p>0.05). There was no statistically significant difference in the mean CVI, SFCT, N1, and T1 values between the groups (p>0.05); however, the mean T2 and N2 values were significantly higher in the full-term group than in the preterm group (p<0.05). There was a significant positive correlation between the birth week and the T1 (p<0.05) CONCLUSION: Prematurity can affect CT even with no history of ROP. The decreases in CTs were significant at 2000 µm nasal and temporal from the fovea. The impairment of temporal choroidal region was more evident than nasal choroidal region. The mean CVI values were similar between the groups.

Effect of obstructive sleep apnoea syndrome and continuous positive airway pressure treatment on choroidal structure.

OBJECTIVES: To evaluate the effect of obstructive sleep apnoea syndrome (OSAS) and continuous positive airway pressure (CPAP) therapy on choroidal structural changes and choroidal vascularity index (CVI) in patients with OSAS. METHODS: Choroidal structural changes in patients with OSAS immediately after diagnosis and 12 months after CPAP treatment were evaluated and compared with healthy controls. The choroidal images on enhanced depth imaging optical coherence tomography (EDI-OCT) were binarized into luminal area (LA) and stromal area (SA) using the ImageJ software. CVI was calculated as the ratio of LA to total choroid area (TCA). The correlations between the results of polysomnography (PSG) and choroidal parameters were evaluated. RESULTS: A total of 48 eyes of 48 patients (22 patients with OSAS, and 26 controls) were included. The mean age of the patients was 47.21 ± 8.82 (range, 30-63) years. The mean CVI values were 68.10 ± 1.80% in the OSAS group before CPAP therapy, and 69.22 ± 1.40% in the control group (p < 0.05). After 12 months of regular CPAP therapy, the mean CVI value increased significantly to 69.15 ± 1.77%, and SA decreased significantly from 0.51 ± 0.07 mm2 to 0.48 ± 0.07 mm2 in the OSAS group (p < 0.05). No statistically significant correlation was found between the results of PSG and choroidal structural parameters. CONCLUSION: According to our results, OSAS was associated with increased stromal oedema in the choroid, which improved after 12 months of regular CPAP therapy. CVI can be an important parameter for the follow-up of patients with OSAS.

Evaluation of ocular biometric parameters in keratoconic eyes relative to healthy myopic eyes.

OBJECTIVE: To assess the biometric features of keratoconic eyes using the Lenstar LS900 and Pentacam systems relative to healthy myopic eyes. MATERIALS AND METHODS: Seventy-three eyes of keratoconic subjects and 83 eyes of control subjects were enrolled. To evaluate the reproducibility of the Lenstar and Pentacam devices' measurements, keratometric readings [in flattest meridian (Kf), in steepest meridian (Ks), and mean (Km)], central corneal thickness (CCT), and anterior chamber depth (ACD) were obtained using both systems. Axial length and lens thickness (LT) were measured by the Lenstar. The compatibility between the two devices was investigated using the Bland-Altman statistical method. RESULTS: Axial length was longer in the myopic group than in eyes with keratoconus (24.94 ± 0.7 and 23.88 ± 0.96 mm, respectively, p < 0.001). LT and vitreous depth were also higher in the myopic group, although ACD values were similar. Compared to the Lenstar, the Pentacam measured the ACD and CCT values higher in the myopia group [with a difference of 0.07 ± 0.12 mm (p <0.001) and 4.47 ± 11.33 µm (p = 0.001), respectively] and measured the CCT values higher in the keratoconus group. Pentacam found all keratometry values significantly lower than Lenstar in the keratoconus group. CONCLUSIONS: Axial length was longer in the myopic eyes due to the differences starting from the lens and extending to the posterior segment. Lenstar and Pentacam can be used interchangeably for Km, Kf, and ACD in the myopic group and only for ACD in the keratoconus group.

Comparison of the choroidal structural components and choroidal vascularity index between patients with obstructive sleep apnea syndrome and healthy controls.

AIM: To compare the choroidal structural components and choroidal vascularity index (CVI) between patients with obstructive sleep apnea syndrome (OSAS) and healthy controls. METHODS: The choroidal images of the eyes of patients with OSAS and healthy controls, which were obtained by using enhanced depth imaging optical coherence tomography (EDI-OCT), were binarized into luminal area (LA) and stromal area (SA) using the ImageJ software. CVI was calculated as the ratio of LA to the total choroid area (TCA). The CVI, LA, SA, and TCA measurements were compared between the groups. RESULTS: Seventy-one eyes of 57 patients, 33 eyes of 27 patients with OSAS and 38 eyes of 30 healthy individuals, were included. The mean age of all patients was 46.77±9.75 (range, 30-67) years. There was no statistically significant difference for age, sex, axial length (AL) or the side of the eyes between the groups (p>0.05). The mean body mass index (BMI) of the patients was significantly higher in the OSAS group (p<0.05). The mean CVI value was 68.33±1.81% in the OSAS group and 69.21±1.27% in the control group (p<0.05). There was no statistically significant difference for the mean values of LA, SA, and TCA between the groups (p>0.05). No significant correlation was found between the polysomnography test results and the choroidal measurements (p>0.05). CONCLUSION: In our study, CVI was found to be lower in patients with OSAS than in the healthy controls. Further studies with larger sample sizes are required to evaluate the role of CVI in OSAS.

Agreement of keratometric readings measured using rotating Scheimpflug imaging, auto-refractokeratometer, and biograph in eyes with keratoconus.

AIM: To determine agreement in keratometric readings obtained using rotating Scheimpflug imaging with Pentacam, biograph with Lenstar LS900, and Topcon KR-8100P auto-keratorefractometer in eyes with different stages of keratoconus. METHODS: A total of 89 eyes of 58 patients with keratoconus were examined in this study, retrospectively. The eyes were divided into two groups: mild group (group 1: 42 eyes) (Amsler-Krumeich stage 1) and moderate-to-severe group (group 2: 47 eyes) (Amsler-Krumeich stage 2, 3, 4). The keratometric readings measured using the Pentacam Scheimpflug system, Lenstar LS900, and Topcon KR-8100P auto-keratorefractometer were compared between the groups. The effects of the measurements of anterior chamber depth, Q value, axial length, central corneal thickness (CCT), and maximum value of keratometry (Kmax) on the differences of devices for keratometric readings were investigated. RESULTS: The mean values of the keratometric readings obtained using the Lenstar were steeper than with the Pentacam and Topcon, especially in group 2. In group 1, the mean K2 values measured using the Lenstar were significantly steeper than with the Topcon (p < 0.05); however, the devices were accordant for the other keratometric readings. In group 2, there was an agreement between the Pentacam and Topcon for the mean K1 and Km values; however, there were significant differences between the devices for the other values. The Q value and CCT had a negative correlation, and Kmax had a positive correlation with the differences of Lenstar-Pentacam and Lenstar-Topcon (p < 0.01). CONCLUSION: According to our results, Pentacam-Topcon and Pentacam-Lenstar can be used interchangeably for keratometry in mild stages of keratoconus. The keratometric readings of Lenstar were found steeper than the other devices with increasing grades of keratoconus. None of these devices can be used interchangeably in moderate-to-severe stages of keratoconus.

Structural assessment of the optic nerve in patients with obstructive sleep apnea syndrome: Case-control study.

OBJECTIVE: Obstructive sleep apnea syndrome has been identified as a possible risk factor for optic nerve pathology such as glaucoma, nonarteritic ischemic optic neuropathy, and optic disk edema. Accordingly, we aimed to evaluate structural changes of the apparently normal optic nerve in obstructive sleep apnea syndrome patients with effects of its severity. MATERIALS AND METHODS: In this prospective case-control study, 47 eyes of 47 obstructive sleep apnea syndrome patients diagnosed with polysomnography and 40 eyes of 40 healthy subjects were included. Spectral-domain optical coherence tomography was used to evaluate the peripapillary retinal nerve fiber layer thickness, optic nerve head topographic parameters, and retinal ganglion cell-inner plexiform layer thickness. RESULTS: The average peripapillary nerve fiber layer thickness was lower in obstructive sleep apnea syndrome patients than in controls (90.74 ± 7.98 vs 94.93 ± 6.13 µm; p = 0.008). The average cup/disk ratio and the vertical cup/disk ratio in patients with OSAS were significantly higher compared to the controls (both p < 0.001). However, no significant difference in retinal ganglion cell-inner plexiform layer thickness was found. CONCLUSION: Even if the retinal ganglion cell-inner plexiform layer thicknesses did not significantly differ between the obstructive sleep apnea syndrome and control groups, obstructive sleep apnea syndrome patients showed a decreased peripapillary nerve fiber layer thickness and increased optic nerve head parameters. These findings can be used as an indicator of optic nerve damage in the early diagnosis of obstructive sleep apnea syndrome patients.

Combined treatment of transluminal Nd:YAG laser embolysis and hyperbaric oxygen for branch retinal artery occlusion.

Objective: To describe the clinical efficiency of transluminal Nd:YAG laser embolysis (TYE) and hyperbaric oxygen (HBO) as an off-label combined treatment for branch retinal artery occlusion (BRAO) with visible emboli. Methods: A 77-year-old woman had a history of seeing a "shadow" in the lower visual field of the left eye for three days. Platelet-fibrin embolus at the arterial bifurcation was disintegrated by TYE technique and the patient was referred to HBO treatment for 20 sessions. Results: One week after treatment, best-corrected visual acuity improved to 0.8 while a good arterial blood flow in the affected branch was seen. Platelet fibrin plaques had disappeared at fundus, and the pale appearance in the retina had decreased. Conclusions: TYE and HBO combination treatment may be an effective and feasible treatment for restoration of blood flow and vision in BRAO cases caused by visible platelet-fibrin emboli.

Effect of Therapy on Choroidal Thickness in Patients With Obstructive Sleep Apnea Syndrome.

BACKGROUND AND OBJECTIVE: To evaluate effect of continuous positive airway pressure (CPAP) therapy on choroidal thickness in patients with obstructive sleep apnea syndrome (OSAS). PATIENTS AND METHODS: Thirty distinct eyes of 30 patients with OSAS were evaluated right before and 12 months after CPAP treatment in this prospective observational study. Choroidal thickness was measured at the fovea and with periodic intervals of 500 µm from the foveal center in both temporal and nasal directions using spectral-domain optical coherence tomography in enhanced depth imaging mode. RESULTS: The patients' mean age was 45.33 years ± 7.74 years, and there were eight females and 22 males. After CPAP therapy, the choroidal thicknesses were increased significantly at the subfoveal, 500 µm nasal to the fovea, 500 µm temporal to the fovea, and 1,000 µm temporal to fovea points (P < .05). However, none of retinal macular parameters were significantly different in statistical terms between the two measurements (P > .05). CONCLUSIONS: CPAP therapy had a significant influence on choroidal thickness in patients with OSAS, providing an increase in choroidal thicknesses after 12 months. The determination of an increase in choroidal thickness may be useful to reveal the effects of CPAP therapy and also may be one of the mechanisms to improve choroidal function. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:846-851.].

Diurnal variation in choroidal thickness and body temperature / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate how body temperature (BT) affects choroidal thickness (CT) according to measurements taken with enhanced depth imaging optical coherence tomography (EDI-OCT).METHODS: In this prospective study, the CT of 41 healthy patients was measured hourly from 9∶00 to 17∶00 at the fovea (SF-CT), 500 μm nasal to the fovea(N-CT), and 500 μm temporal to the fovea (T-CT) using EDI-OCT.BT was also measured hourly from 9∶00 to 17∶00 using a non-contact infrared thermometer.Possible correlations between diurnal variations of CT and BT were evaluated.RESULTS: SF-CT values significantly differed between measurements at 9∶00 and 13∶00 (P=0.021), 9∶00 and 14∶00 (P=0.012), 9∶00 and 16∶00 (P=0.048), and 9∶00 and 17∶00 (P=0.002).N-CT values also significantly differed between measurements at 9∶00 and 13∶00 (P=0.004), though T-CT did not significantly vary during the 8h period (P >0.05 for all).CONCLUSION: CT is not significantly associated with hourly changes in BT from 9∶00 to 17∶00.

Effect of Hydroxychloroquine on the Retinal Layers: A Quantitative Evaluation with Spectral-Domain Optical Coherence Tomography.

Purpose. To evaluate the effect of hydroxychloroquine on retinal pigment epithelium- (RPE-) Bruch's membrane complex, photoreceptor outer segment, and macular ganglion cell-inner plexiform layer (GCIPL) thicknesses using spectral-domain optical coherence tomography (SD-OCT). Methods. In this prospective case-control study, 51 eyes of 51 hydroxychloroquine patients and 30 eyes of 30 healthy subjects were included. High-quality images were obtained using a Cirrus HD-OCT with 5-line raster mode; the photoreceptor inner segment (IS) and outer segment (OS), sum of the segments (IS + OS), and RPE-Bruch's membrane complex were analyzed. Results. The thicknesses of the IS + OS and OS layers were significantly lower in the hydroxychloroquine subjects compared to the control subjects (P < 0.05). RPE-Bruch's membrane complex thicknesses were significantly higher in the hydroxychloroquine subjects than for those of the control subjects (P < 0.05). The minimum and temporal-inferior macular GCIPL thicknesses were significantly different between the patients with hydroxychloroquine use and the control subjects (P = 0.04 and P = 0.03, resp.). Conclusions. The foveal photoreceptor OS thinning, loss of GCIPL, and RPE-Bruch's membrane thickening were detected in patients with hydroxychloroquine therapy. This quantitative approach using SD-OCT images may have important implications to use as an early indicator of retinal toxicity without any visible signs of hydroxychloroquine retinopathy.

Retinopathy of prematurity: incidence, risk factors, and evaluation of screening criteria.

BACKGROUND/AIM: The goal of this study was to investigate the incidence of retinopathy of prematurity (ROP) and the relationship between risk factors and disease in premature newborns in our neonatal intensive care unit. MATERIALS AND METHODS: A total of 219 premature subjects were retrospectively evaluated for retinopathy. Demographic information, clinical data, and risk factors were reviewed. RESULTS: The gestational ages of the infants included in the study ranged between 25 and 36 weeks, and the birth weights ranged between 670 and 4460 g. In this study, the incidence of ROP was 20.1% (44) in preterm infants: 16 had stage 1 (36.4%), 15 had stage 2 (34.1%), 11 had stage 3 (25%), 1 had stage 4 (2.3%), 1 had stage 5 (2.3%), and 6 had plus (+) disease (7.2%). The risk factors associated with the development of ROP included low birth weight, ventilation treatment, bronchopulmonary dysplasia, and maternal preeclampsia. The risk factors were analyzed with logistic regression analysis. The odds ratios were 5.952 (95% confidence interval [CI]: 2.030-17.447), 20.070 (95% CI: 4.213-95.600), 5.879 (1.916-18.037), and 3.200 (95% CI: 1.002-11.535), respectively. CONCLUSION: In this study, birth weight, ventilation treatment, bronchopulmonary dysplasia, and maternal preeclampsia were the most important risk factors for the development of ROP.

Comparison of corneal topographic measurements and high order aberrations in keratoconus and normal eyes.

PURPOSE: The aim of this report was to compare corneal topographic measurements and anterior high order corneal aberrations in eyes with keratoconus and normal eyes by using Scheimpflug-Placido topography. METHODS: Eighty cases diagnosed with mild (group 1), moderate (group 2), and advanced (group 3) stage keratoconus (KC) according to Amsler-Krumeich Classification and 81 healthy (control group) cases were retrospectively examined. The mean keratometric measurements (as both diopters (Kavg) and mm values (mmavg)), central corneal thickness values (CCT), high order aberration (HOA), total wavefront aberration (TWA), coma, trefoil, and spherical aberration measurements were performed using Sirius topography equipment. The topographic values were compared between the groups. RESULTS: There were 25 cases in group 1 KC (15.5%), 34 cases in group 2 KC (21.1%), 21 cases in group 3 KC (13.1%), and 81 cases (50.3%) in the control group. In terms of mean age and gender distributions, there was no statistically significant difference between the groups (p>0.05). However, there was significant difference between the groups in terms of Kavg, CCT, HOA, TWA, coma, trefoil, and spherical aberration values (p<0.01). Mean HOA, TWA, coma, trefoil, and spherical aberration values were observed to increase with the severity of KC disease. CONCLUSIONS: Anterior high order corneal aberrations were significantly increased in eyes with moderate and advanced keratoconus. Anterior high order corneal aberration measurements are a useful tool to guide the physician in diagnosis and classification of keratoconus.

Retinal nerve fiber layer, ganglion cell complex, and choroidal thicknesses in migraine.

PURPOSE: To evaluate the thicknesses of the peripapillary retinal nerve fiber layer (RNFL), ganglion cell complex (GCL), and choroid layer using spectral domain optical coherence tomography (SD-OCT) for investigating the effects of vascular changes on the eye and optic nerve in patients who have migraine with aura. METHODS: Forty-five patients who had migraine with aura (migraine group) and 45 healthy individuals (control group) were enrolled in the study. Age, gender, duration after migraine diagnosis, intraocular pressure, and axial length measurements were recorded in each case. RNFL, GCL, and choroid layer thicknesses were measured using SD-OCT in all participants. RESULTS: The mean age was 36.1 ± 6.7 (20-45) years in the migraine group and 35.7 ± 8.6 (19-45) years in the control group. There was no significant difference in the RNFL thicknesses of the temporal and nasal quadrants (p >0.05). The RNFL thicknesses of the superior and inferior quadrants were significantly lower in the migraine group compared with those in the control group (p =0.001, p <0.01, respectively). Measurements for the superior and inferior GCL were not significantly different between the groups (p >0.05). Subfoveal, temporal, and nasal choroidal thickness measurements at 500 µm, 1000 µm, and 1500 µm were significantly lower in the migraine group than in the control group (p =0.001; p <0.01, respectively). CONCLUSIONS: Compared with the controls, the RNFL and choroid layer were determined to be thinner in patients who had chronic migraine with aura.

A PILOT STUDY OF CHOROIDAL THICKNESS IN LONG-TERM SMOKERS.

PURPOSE: To compare the choroidal thicknesses in long-term smokers with those of nonsmoking healthy individuals using spectral domain optical coherence tomography. PARTICIPANTS: Forty-six individuals who had been smoking at least for 20 years, but otherwise without systemic problems, participated in this prospective pilot study. The control group comprised 42 nonsmoking individuals. METHODS: The ages, refractions, and axial length measurements of the cases were recorded. Central macular thickness and choroidal thickness at the fovea and at 500 µm intervals from the foveal center in both temporal and nasal directions were measured using spectral domain optical coherence tomography. RESULTS: Although the smoking period of the smokers was mean 32.4 ± 9 years (range: 20-60), the mean pack-years of cigarettes was 35.1 ± 23.8 (range: 10-120). No significant difference was observed regarding refraction value and axial length between smokers and nonsmokers group. In addition, no significant difference was observed for central macular thickness and choroidal thickness values at 500, 1,000, 1,500, and 2,000 µm nasal and temporal part of the fovea, between 2 groups. CONCLUSION: Macular and choroidal thicknesses in long-term smokers were observed to be similar to those of healthy individuals.

Retinal nerve fiber layer, ganglion cell complex, and choroidal thicknesses in migraine / Espessuras da camada de fibras nervosas retinianas, complexo de células ganglionares e coroide na enxaqueca

ABSTRACT Purpose: To evaluate the thicknesses of the peripapillary retinal nerve fiber layer (RNFL), ganglion cell complex (GCL), and choroid layer using spectral domain optical coherence tomography (SD-OCT) for investigating the effects of vascular changes on the eye and optic nerve in patients who have migraine with aura. Methods: Forty-five patients who had migraine with aura (migraine group) and 45 healthy individuals (control group) were enrolled in the study. Age, gender, duration after migraine diagnosis, intraocular pressure, and axial length measurements were recorded in each case. RNFL, GCL, and choroid layer thicknesses were measured using SD-OCT in all participants. Results: The mean age was 36.1 ± 6.7 (20-45) years in the migraine group and 35.7 ± 8.6 (19-45) years in the control group. There was no significant difference in the RNFL thicknesses of the temporal and nasal quadrants (p >0.05). The RNFL thicknesses of the superior and inferior quadrants were significantly lower in the migraine group compared with those in the control group (p =0.001, p <0.01, respectively). Measurements for the superior and inferior GCL were not significantly different between the groups (p >0.05). Subfoveal, temporal, and nasal choroidal thickness measurements at 500 µm, 1000 µm, and 1500 µm were significantly lower in the migraine group than in the control group (p =0.001; p <0.01, respectively). Conclusions: Compared with the controls, the RNFL and choroid layer were determined to be thinner in patients who had chronic migraine with aura.

RESUMO Objetivo: Avaliar as espessuras de camada peripapilar de fibras nervosas retinianas (RNFL), complexo de células ganglionares (GCL) e da coroide utilizando a tomografia de coerência óptica de domínio espectral (SD-OCT), a fim de investigar os efeitos das alterações vasculares no olho e nervo óptico em pacientes que apresentam enxaqueca com aura. Métodos: Quarenta e cinco pacientes que apresentavam enxaqueca com aura (grupo enxaqueca) e 45 indivíduos saudáveis (grupo controle) foram incluídos no estudo. Idade, sexo, duração da enxaqueca, pressão intraocular e medidas de comprimento axial foram registrados em cada caso. Medidas da RNFL, GCL e espessuras da coroide foram obtidas com SD-OCT em todos os participantes. Resultados: A média da idade foi de 36,1 ± 6,7 (20-45) anos no grupo enxaqueca e 35,7 ± 8,6 (19-45) anos no grupo controle. Não houve diferença significativa em espessuras RNFL nos quadrantes temporal e nasal (p>0,05). A espessura da RNFL nos quadrantes superiores e inferiores foram significativamente menores no grupo de enxaqueca em comparação ao grupo controle (p=0,001; p<0,01). Medidas da GCL superior e inferior não mostraram diferença significativa entre os grupos (p>0,05). Espessuras subfoveais, temporais e nasais da coroide (CT) a 500 µm, 1000 µm e 1500 µm foram significativamente menores no grupo de enxaqueca em relação ao grupo controle (p=0,001; p<0,01). Conclusões: Comparados aos controles, as espessuras da RNFL e coroide foram mais finas em pacientes que apresentavam enxaqueca crônica com aura.

Choroidal and peripapillary retinal nerve fiber layer thickness in adults with anisometropic amblyopia.

PURPOSE: To evaluate choroidal thickness, macular thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness in amblyopic eyes compared to fellow and normal control eyes using high-definition spectral-domain optical coherence tomography (SD-OCT). METHODS: Fifty-four without any systemic problem and ocular disease participated in this prospective study. Inclusion criteria included individuals older than 18 years with anisometropic amblyopia. Choroidal thickness, central macular thickness (CMT), and RNFL thickness were measured by using enhanced depth imaging SD-OCT. The choroidal thickness was measured at the fovea and at 500 µm intervals from the foveal center in both temporal and nasal directions. Axial length measurements of the cases were also recorded. RESULTS: Mean peripapillary RNFL thickness of the amblyopic, fellow, and control eyes was 107.5 ± 15.5 µm, 109.3 ± 12.7 µm, and 108.8 ± 8.6 µm, respectively (p = 0.343). The average CMT was 231.7 ± 14.7 µm in amblyopic eyes, 232.5 ± 15.7 µm in fellow eyes, and 230.8 ± 14.8 µm in control eyes (p = 0.599). Mean subfoveal choroidal thickness was significantly greater in the amblyopic eyes than in the fellow and control eyes (396.3 ± 104.3 µm, 361.0 ± 103.9 µm, 390.6 ± 91.7 µm). Mean axial measurement in amblyopic eyes was 22.7 ± 1.3 mm (20.5-26.1), in fellow eyes 23.1 ± 0.9 mm (20.9-25.0), and in control eyes 23.3 ± 0.9 mm. CONCLUSIONS: In adults with anisometropic amblyopia, subfoveal, temporal, and nasal choroidal thickness of amblyopic eyes are significantly thicker than in fellow eyes. However, no significant differences in peripapillary RNFL thickness or CMT were found between amblyopic and fellow or control eyes.

Corneal collagen crosslinking for ectasia after laser in situ keratomileusis: long-term results.

PURPOSE: To report the long-term results of corneal collagen crosslinking (CXL) treatment for post-laser in situ keratomileusis (LASIK) ectasia. SETTINGS: Turkiye Hospital Eye Clinic and Fatih University Medical Faculty, Department of Ophthalmology, Istanbul, Turkey. DESIGN: Retrospective case series study. METHODS: Consecutive patients with ectasia after LASIK were treated with CXL. The main outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuities, spherical and cylindrical refractions, and simulated keratometry (K) values. RESULTS: The study enrolled 20 eyes (14 patients; 7 women) with a mean age of 34.8 years ± 6.0 (SD) (range 25 to 45 years) and mean follow-up of 42 months (range 36 to 60 months). The UDVA and CDVA improved significantly, from 0.78 ± 0.61 logMAR to 0.53 ± 0.36 logMAR (P=.007) and from 0.27 ± 0.23 logMAR to 0.19 ± 0.13 logMAR, respectively (P≤.028). No eye lost 1 or more Snellen lines of UDVA or CDVA. Although the mean spherical refraction was not significantly different at the last visit (P=.074), the mean cylindrical refraction decreased significantly (P=.036). The maximum K value decreased from 46.0 ± 4.4 diopters (D) at baseline to 45.6 ± 3.8 D at the last visit (P=.013). By the last visit, the maximum K value decreased (≥1.0 D) in 5 eyes and remained stable in 15 eyes. No serious complications occurred. CONCLUSIONS: Corneal collagen crosslinking yielded long-term stability in cases with post-LASIK corneal ectasia without significant side effects. Improvements in visual acuity, cylindrical refraction, and maximum K values occurred. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Long-term outcomes of intrastromal corneal ring segment implantation for post-LASIK ectasia.

PURPOSE: To report the long-term results of intrastromal corneal ring segments (ICRS) for postoperative LASIK ectasia. METHOD: In this retrospective interventional cases series, 8 eyes of 6 patients who underwent femtosecond laser-assisted ICRS implantation for post-LASIK ectasia were enrolled. Main outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent refraction, and average keratometry (Kavg) values were assessed. RESULTS: Mean±SD follow-up was 67±21 months (range, 36-96 months). The mean UDVA, CDVA, spherical equivalent refraction, and Kavg values were significantly improved at all postoperative visits when compared to baseline values. No serious complications were observed during follow-up. CONCLUSION: Our long-term findings showed that ICRS yielded improvements in visual acuity, refractive status, and keratometric values without any progression in cases with post-LASIK corneal ectasia.

Risk Factors in Post-LASIK Corneal Ectasia.

Purpose. To evaluate the risk factors for post-laser in situ keratomileusis (LASIK) ectasia. Materials and Methods. Medical records of 42 eyes of 28 (10 women, 18 men) patients who developed corneal ectasia after LASIK were retrospectively reviewed. Topographical features and surgical parameters of those patients were evaluated. Results. The mean age of patients was 34.73 ± 6.50 (23-48) years and the mean interval from LASIK to the diagnosis of post-LASIK ectasia was 36.0 ± 16.92 (12-60) months. The following factors were determined as a risk factors: deep ablation (>75 µ m) in 10 eyes, FFK (forme fruste keratoconus) in 6 eyes, steep cornea (>47 D) in 3 eyes, pellucid marginal degeneration (PMD) in 2 eyes, thin cornea (<500 µ m) in 2 eyes, thin and steep cornea in 2 eyes, thin cornea and deep ablation in 5 eyes, FFK and steep cornea in 2 eyes, and FFK, steep cornea, and deep ablation in 1 eye. However no risk factor has been determined in 9 eyes (21.4%). Conclusion. The findings of our study showed that most of the patients who developed post-LASIK ectasia have a risk factor for post-LASIK ectasia. However, the most common risk factor was deep ablation.