Comparison of surgically induced astigmatic changes after cataract surgery in post-Laser in situ keratomileusis corneas versus virgin eyes.

PURPOSE: Postoperative refraction in modern mi-croincision cataract surgery gained extra importance in patients with the previous laser-assisted in situ keratomileusis (LASIK) surgery. The surgically induced astigmatic changes in those eyes may differ not only in magnitude but also in direction compared to virgin corneas. This study aimed to compare the surgically induced astigmatic changes after microscopic cataract surgery between post-LASIK corneas and virgin eyes. METHODS: Cases that underwent microincision cataract surgery in eyes with and without previous LASIK surgery were reviewed. The demographics, the axial length at cataract surgery, the central corneal thickness, spheric and cylindric values, keratometry readings, and postoperative posterior corneal astigmatism were retrospectively evaluated. A modified Alpins method was used for astigmatic vector analysis, and baseline astigmatism, surgically induced astigmatism, difference vector, flattening effect, and torque were assessed. RESULTS: A total of 42 eyes from 24 subjects was evaluated. Group I consisted of 14 eyes with the previous LASIK, and Group II included 28 eyes without any refractive surgery. Preoperative mean central corneal thickness in Group I was significantly thinner (p=0.012). There was no significant difference in baseline astigmatism between the groups regarding magnitude and power vectors. After microincision cataract surgery, there were no significant differences in mean spheric and cylindric values and mean keratometry readings (all p>0.05). However, surgically induced astigmatism and difference vector were significantly higher on J45 vector component in post-LASIK eyes and microincision cataract surgery steepening effect on post-LASIK corneas was significantly higher than those in virgin eyes (p=0.001, p=0.002 and p=0.018, respectively). CONCLUSIONS: Cataract surgery has steepened the corneas in both groups with a significantly higher steepening effect in post-LASIK eyes. Certainly, corneal topography cataract surgery is particularly helpful to provide more precise surgically induced astigmatism interpretations.

Comparison of surgically induced astigmatic changes after cataract surgery in post-Laser in situ keratomileusis corneas versus virgin eyes / Comparação de alterações astigmáticas induzidas cirurgicamente após cirurgia de catarata em córneas ceratomileusis in situ pós-Laser versus olhos virgens

ABSTRACT Purpose: Postoperative refraction in modern mi­croincision cataract surgery gained extra importance in patients with the previous laser-assisted in situ keratomileusis (LASIK) surgery. The surgically induced astigmatic changes in those eyes may differ not only in magnitude but also in direction compared to virgin corneas. This study aimed to compare the surgically induced astigmatic changes after microscopic cataract surgery between post-LASIK corneas and virgin eyes. Methods: Cases that underwent microincision cataract surgery in eyes with and without previous LASIK surgery were reviewed. The demographics, the axial length at cataract surgery, the central corneal thickness, spheric and cylindric values, keratometry readings, and postoperative posterior corneal astigmatism were retrospectively evaluated. A modified Alpins method was used for astigmatic vector analysis, and baseline astigmatism, surgically induced astigmatism, difference vector, flattening effect, and torque were assessed. Results: A total of 42 eyes from 24 subjects was evaluated. Group I consisted of 14 eyes with the previous LASIK, and Group II included 28 eyes without any refractive surgery. Preoperative mean central corneal thickness in Group I was significantly thinner (p=0.012). There was no significant difference in baseline astigmatism between the groups regarding magnitude and power vectors. After microincision cataract surgery, there were no significant differences in mean spheric and cylindric values and mean keratometry readings (all p>0.05). However, surgically induced astigmatism and difference vector were significantly higher on J45 vector component in post-LASIK eyes and microincision cataract surgery steepening effect on post-LASIK corneas was significantly higher than those in virgin eyes (p=0.001, p=0.002 and p=0.018, respectively). Conclusions: Cataract surgery has steepened the corneas in both groups with a significantly higher steepening effect in post-LASIK eyes. Certainly, corneal topography cataract surgery is particularly helpful to provide more precise surgically induced astigmatism interpretations.

RESUMO Objetivo: A refração pós-operatória na cirurgia mo­derna de catarata por microincisão ganha ainda mais importância em pacientes com cirurgia prévia de ceratomileuse in situ assistida por laser (LASIK). As alterações astigmáticas induzidas cirurgicamente nesses olhos podem diferir não apenas em magnitude, mas também em direção em comparação com córneas virgens. O objetivo deste estudo foi comparar as alterações astigmáticas induzidas cirurgicamente após cirurgia de catarata por microincisão entre córneas pós-LASIK e olhos virgens. Métodos: Foi revisada uma série de casos de cirurgia de catarata por microincisão em olhos com e sem cirurgia LASIK anterior. Os dados demográficos, o comprimento axial no momento da cirurgia de catarata, a espessura central da córnea, os valores esféricos e cilíndricos, as leituras da ceratometria e o astigmatismo corneano posterior pós-operatório foram avaliados retrospectivamente. O método Alpins modificado foi usado para análise vetorial astigmática e foram avaliados o astigmatismo basal, o astigmatismo induzido cirurgicamente, o vetor de diferença, o efeito de achatamento e o torque. Resultados: Ao todo, 42 olhos de 24 indivíduos foram avaliados. O Grupo I consistiu em 14 olhos com LASIK prévio; o Grupo II incluiu 28 olhos sem qualquer cirurgia refrativa. A média da espessura corneana central pré-operatória no Grupo I foi significativamente mais fina (p=0,012). Não houve diferença significativa no astigmatismo basal entre os grupos em termos de magnitude e vetores de potência. Após a cirurgia de catarata por microincisão, não houve diferenças significativas nos valores médios esféricos, cilíndricos e leituras médias de ceratometria (todos com p>0,05). No entanto, o astigmatismo induzido cirurgicamente e o vetor de diferença foram significativamente maiores no componente do vetor J45 em olhos pós-LASIK, e o efeito de aumento da inclinação pela cirurgia de catarata por microincisão nas córneas pós-LASIK foi significativo em comparação com olhos virgens (p=0,001, p=0,002 e p=0,018, respectivamente). Conclusões: A cirurgia de catarata aumentou a inclinação das córneas em ambos os grupos, sendo esse aumento significativamente maior nos olhos pós-LASIK. Certamente, a topografia da córnea antes da cirurgia de catarata é particularmente útil para fornecer interpretações mais precisas do astigmatismo induzido cirurgicamente.

The Effect of Thyroid Eye Disease on Corneal Biomechanical Properties.

Objectives: The aim of this study was to identify corneal biomechanical parameters measured by ORA in patients with TED compared to the healthy group. The NOSPECS classification of patients is used to assess the relation between biomechanical changes and disease severity. Methods: We included 22 TED patients, diagnosed with TED for more than five years, and 43 healthy participants. The NOSPECS classification was assessed as mild (grade 1-3) and severe (grade 4-6) disease. For each group, corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT), Goldmann-correlated intraocular pressure (IOPg) and corneal compensated intraocular pressure (IOPcc) parameters were measured by ORA. Results: The mean age was 38.8±11.6 years for the TED patients and 42.9±15.58 years for the control group. For TED patients and healthy volunteers, the mean levels of CRF, CH, and CCT were measured as follows: 10.43±2.04 vs 10.28±1.91mmHg, p=0.67; 10.18±1.81 vs 10.21±1.68 mmHg, p=0.90; 550.31±35.73 vs 545.23±37.91 µm, p=0.47, respectively. These values were not significant between groups, but they were significantly higher in females compared to males in TED patients [CRF;10.68 (IQR: 9.49-12.14) vs 8.96 (IQR: 8.04-9.92) mmHg, p=0.002, CH; 10.43 (IQR: 9.48-11.25) vs 8.58 (IQR: 7.90-9.95) mmHg, p=0.003 and CCT; 554.25 (IQR: 536.05-579.52) vs 527.40 (IQR: 492.25-545.90) µm, p=0.014]. CRF values were negatively correlated with NOSPECS score (r=-0.317, p=0.036) and significantly higher CRF was observed in mild patients compared to severe disease (11.43 (IQR: 10.14-12.87) vs 9.46 (IQR: 8.75-10.28) mmHg, p=0.008). Conclusion: We found a significant gender effect on corneal biomechanical parameters of TED patients. CRF, CH and CCT values were significantly higher in females compared to males with TED. The clinical severity score of TED showed negative correlation with CRF. CRF value might be a useful parameter in follow-up of TED patients in clinical practice.

Interobserver and Intraobserver Agreements of the Detection of Demodex Infestation by in Vivo Confocal Microscopy.

Objectives: The purpose of the study was to determine interobserver and intraobserver agreement, repeatability, and intrasubject variation of the detection of Demodex infestation in eyelids of blepharitis patients using in vivo confocal microscopy (IVCM). Methods: Eighty-three eyes of 42 blepharitis patients were included in the study. All eyelids were evaluated from temporal to nasal with IVCM using section mode and 10 lashes with their follicles were imagined, and every image with suspicion of Demodex infestation was recorded. Two experienced and two inexperienced ophthalmologists were masked for the diagnosis and interpreted the IVCM images regarding the presence of Demodex infestation with a 3-week interval. Interobserver and intraobserver agreements were calculated with Cohen's kappa and its variant statistics between and within experienced observers and between inexperienced observers. Results: While average sensitivity for the diagnosis of demodicosis in IVCM images was 83.35% for experienced and 51.35% for inexperienced observers, the average positive predictive value was 88.6% for experienced observers and 91.05% for inexperienced ones. Interobserver agreement between experienced observers was moderate (κ = 0.529) and intraobserver agreements within experienced observers were perfect (κ = 0.918 for observer-1; κ = 0.958 for observer-2). Interobserver agreement between inexperienced observers was poor (κ = 0.162) and intraobserver agreements within inexperienced observers were fair (κ = 0.427 for observer-3; κ = 0.475 for observer-4). Conclusion: The sensitivity, interobserver and intraobserver agreements in IVCM image analysis for the detection of Demodex infestation were highly associated with the clinical experience on IVCM imaging. In the hands of an experienced clinician, IVCM could be reliable for the diagnosis of ocular demodicosis.

Comparison of Postoperative Corneal Astigmatism Induced by Two Different Corneal Incisions during Microincisional Cataract Surgery.

Objectives: Clear corneal incision (CCI) architecture in modern microincision cataract surgery (MICS) plays an undeniable role in postoperative refraction. The goal of this study was to evaluate the effect of hinge incision prior to two-step CCI on postoperative refractive astigmatism after cataract surgery and to demonstrate the schematic presentation of these postoperative astigmatic changes via double-angle polar plots. Methods: This study involved a consecutive case series of patients who had MICS. The first incision was performed as a two-step CCI, whereas the second was made as a hinge incision prior to 2-step CCI. The preoperative corneal and postoperative refractive astigmatism and surgically induced astigmatism (SIA) were calculated by vectorial analysis. Hotelling's T2 test was performed to compare the centroid values of preoperative and postoperative corneal astigmatism. Results: A total of 63 eyes from 57 subjects were evaluated. Group I consisted of 27 eyes with the two-step CCI, and Group II included 36 eyes with the hinge incision prior to two-step CCI. No significant difference was found between the groups in terms of age, sex, axial length, keratometry readings, implanted intraocular lens power, and postoperative spherical equivalent. The centroids of corneal astigmatism postoperatively increased to 0.21 D at 87.6°±0.61 with no significance in Group I (p=0.525) and to 0.70 D at 90.6°±0.47 with significance in Group II (p=0.032). The difference in postoperative centroids between the two groups was also significantly different (p=0.043). Finally, the centroids of SIA were 0.12 D at 85.5°±0.50 and 0.22 D at 91.1°±0.49 for Group I and Group II, respectively, with no significance. Conclusion: A hinge incision did not have an unfavorable effect on postoperative refractive astigmatism; therefore, it may be preferred for controlled entrance to the anterior chamber.

Peripapillary Choroidal Vasculature in Pediatric Eyes with Type 1 Diabetes Mellitus.

Objectives: Choroidal vasculature change in children with diabetes mellitus is not investigated enough although it could reflect clinical outcome. Methods: Pediatric Type 1 diabetes mellitus (T1DM) patients and healthy controls were retrospectively evaluated. Peripapillary retinal nerve fiber layer optical coherence tomography (OCT) images of the right eyes were analyzed. Choroidal parameters including total choroidal area, luminal area, stromal area, and choroidal vascularity index were measured through image binarization. Results: Twenty eyes of 20 patients were compared with 46 eyes of 46 healthy controls. Mean total choroidal area, luminal area, and stromal area were 1.59±0.35, 1.10±0.24, and 0.50±0.13 mm2 in patients' eyes and 1.52±0.49, 1.05±0.34, and 0.47±0.17 mm2 in healthy eyes. No difference was found in choroidal vascularity indices between patients and healthy eyes (68.8±3.9% vs. 69.4±4.4%, p=0.521). Temporal choroidal vascularity index was significantly higher than its nasal counterpart in healthy eyes (71.8±5.0% vs. 68.6±4.9%, p<0.001) which was not significant in patients' eyes (70.7±4.0% vs. 68.9±5.1%, p=0.067). Temporal quadrant had the highest choroidal vascularity index score among all quadrants in healthy controls (all p<0.05), whereas no choroidal vascularity index difference between quadrants was detected in patients (p=0.75). Conclusion: Peripapillary choroidal vasculature has shown subtle sectoral changes which did not reflect the overall peripapillary OCT section in pediatric T1DM patients when compared with healthy controls.

Survey of the Impact of the COVID-19 Pandemic on Ophthalmology Clinical Practice in Turkey

Objectives: To investigate the effect of the novel coronavirus disease 2019 (COVID-19) pandemic on the clinical practice of ophthalmologists in our country. Materials and Methods: A questionnaire consisting of 22 questions was delivered to 250 ophthalmologists via e-mail and a smartphone messaging application. A total of 113 ophthalmologists completed the survey. The questions included the participants' demographic data (age, years in practice, institution, and city), changes in their working conditions and institutional preventive measures implemented during the pandemic, their personal COVID-19 experiences, the prevalence of telemedicine applications, and their attitudes toward these practices. Results: Nearly half (47.8%) of the 113 ophthalmologists were 36 to 45 years old. In terms of years in practice, the largest proportion of respondents (28.3%) had 6-10 years of experience. Most of the participants worked in private/foundation universities (37.2%), while 22.1% worked in education and research clinics. Participants working at public universities most often reported that they or a close contact had to work in COVID wards (89.5%). Triage was performed in 51.5% of ophthalmology outpatient clinics, with 88.0% of these participants reporting that patients with fever, cough, or dyspnea were directed to the pandemic clinic without ophthalmological examination. All participants working in public hospitals, education and research clinics, and public university hospitals had postponed elective surgeries, whereas 12.5% of those working in private practice and 20.5% of those working in private/foundation universities reported that they continued elective surgeries. While 80.8% of the participants did not conduct online interviews or examinations, 40.4% stated that they considered telemedicine applications beneficial. Seventy-seven percent of participants expressed concern about a decrease in their income during the pandemic, with this being especially common among participants working in private practice (87.5%) and private/foundation university hospitals (85.7%). Conclusion: Ophthalmologists across our country have been affected by this pandemic at a level that will change their clinical approach. We think that ophthalmologists impacted by the difficulty of providing personal protective equipment and economic concerns should be supported more during the pandemic.

Fungal Keratitis, or Misled by a Small Insect?

The pine processionary caterpillar is an insect that has multiple small, thin hairs around its body as a defense mechanism. These hairs have a hazardous effect on ocular structures and cause a broad range of reactions from conjunctivitis to endophthalmitis, referred to as ophthalmia nodosa. The diagnosis of the disease is based on the patient's history and the detection of the hairs on ocular structures. In this report, we present a patient with ophthalmia nodosa misdiagnosed as fungal keratitis, and the actual diagnosis was made by in vivo confocal microscopy. We also would like to increase awareness among ophthalmologists about the disease which has a growing distribution area due to climate change.

Androgen Suppresses Hyperosmolarity-Induced Inflammatory Mediators in Human Corneal Epithelial Cells.

PURPOSE: To investigative the effects of sex steroids on hyperosmolar stress-induced proinflammatory cytokine expression of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-8, and IL-6, and on the mitogen-activated protein kinase pathway in immortalized human corneal epithelial cells (hCECs). METHODS: Immortalized hCECs were cultured with keratinocyte-free medium until reaching 80% confluency with either 10 M dihidrotestosteron (DHT) or 10 M 17-ß-estradiol, and then, the medium was changed to hyperosmolar for various time points. After hyperosmolar treatment, a real-time polymerase chain reaction was performed to show the TNF-α, IL-8, and IL-6 gene expression levels in hCECs. In addition, the treated cells were lysed, and Western blot analysis was applied for phosphorylated and nonphosphorylated forms of extracellular signal-regulated kinase 1/2 (ERK1/2), p38 kinase, and c-Jun N-terminal kinase 1/2 (JNK1/2). hCECs viability was measured with Annexin V/propidium iodide. RESULTS: Pretreatment with 10 M DHT or 17-ß-estradiol inhibited the high osmolarity-induced expression of TNF-α, IL-8, and IL-6. The upregulation of p-ERK, p-JNK, and p-p38 with high osmolarity was inhibited partially by DHT, but 17-ß-estradiol pretreatment only affected p-p38 for a short time interval. In addition, DHT increased cell viability of hCECs under hyperosmolar conditions. CONCLUSIONS: Our results demonstrated that DHT and 17-ß-estradiol decreased the proinflammatory cytokine gene expression levels which were stimulated by high osmolarity in immortalized hCECs. The mitogen-activated protein kinase signaling pathway is partially involved in the regulatory effects of DHT on hCECs. These findings may contribute to the etiologic role and therapeutic implications of sex steroids in certain ocular surface diseases.

Keratopigmentation: Is it a Miracle or an Adventure?

OBJECTIVES: This study is an analysis of the cosmetic and functional results of patients who underwent keratopigmentation (KTP). METHODS: Sixteen eyes of 16 patients, 7 females (43.75%) and 9 males (56.25%) were included in the study. Intrastromal and superficial manual KTP were performed under general anesthesia. Patients with no light perception or with only light perception but total corneal opacification, prosthetic contact lens intolerance, or unwillingness to use a contact lens were studied. The main outcomes were postoperative patient's satisfaction, cosmetic results, pigment stabilization and surgical complications. A grading system (0-5 points) was used to assess patient satisfaction and the cosmetic results. RESULTS: The mean age of the patients was 30.5±12.06 years (range: 16-53 years). Black pigment was used in 10 patients (62.5%), a brownish color in 5 patients (31.25%) and a greenish, yellow, blue, and black color pigmentation was used for 1 patient (6.25%). The mean follow-up was 29.31±15.45 months (range: 8-52 months). In 2 of 16 patients, mild to moderate pigment loss was seen 12 months after the surgery and superficial KTP was repeated. Minimal pigment loss was seen in 5 patients, but the cosmetic results were satisfactory and no secondary surgical procedure was required. Pigment leakage underneath the conjunctiva was seen in only 1 patient. Otherwise, there were no complications associated with keratopigmentation. The postoperative mean patient satisfaction score was 4.18±0.75 points (range: 3-5 points). CONCLUSION: KTP is a safe surgical procedure that is easy to learn and perform, does not require expensive materials, and avoids more extensive and invasive reconstructive ocular procedures. Corneal KTP may have a great impact on future ophthalmic surgical practice from both therapeutic and cosmetic perspectives.