Refractive and topographic effects of single-segment intrastromal corneal ring segments in eyes with moderate to severe keratoconus and inferior cones.

PURPOSE: To evaluate the efficacy and safety of a single intrastromal corneal ring segment (ICRS) (450 µm Intacs SK) in moderate to severe keratoconic eyes with an inferiorly located cone and a noninvolved center. SETTING: Ophthalmology Department, American University of Beirut Medical Center, Beirut, Lebanon. DESIGN: Retrospective case series. METHODS: The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, central and inferior maximum topographic keratometry (K) values, manifest cylinder, and spherical equivalent (SE) were recorded preoperatively and 1 week and 1, 3, and 6 months postoperatively. RESULTS: Thirty eyes were studied. The mean age was 29.6 years ± 8.0 (SD). The mean preoperative UDVA and CDVA were 20/86 and 20/42, respectively. The mean center K was 49.14 ± 4.39 diopters (D); the mean maximum K, 56.78 ± 6.02 D; and the mean center K - maximum K, -7.45 ± 5.61 D. The mean SE and cylinder were -2.24 ± 2.32 D and -4.33 ± 1.43 D, respectively, with sphere ranging from +2.00 to -18.00 D. At 6 months, the UDVA improved to 20/32. The mean SE was -1.02 ± 2.04 D (P = .0330); the mean cylinder, -1.67 ± 1.00 D (P < .00); and the mean center K - maximum K, -4.92 ± 4.36 D (P < .05). The CDVA improved more than 2 lines; no eye lost any lines. Topographic indices improved in all eyes. CONCLUSIONS: Single ICRS implantation in eyes with moderate to severe keratoconus and inferiorly located cones was safe and effective. The development of a nomogram relying more on topographic data is suggested. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Static cyclotorsion measurements using the Schwind Amaris laser.

PURPOSE: To assess the reliability and reproducibility of static cyclotorsion correction (SCC) measurements made using the Schwind Amaris Excimer laser in patients undergoing LASIK or PRK, and compare the outcomes of treating astigmatism with and without SCC. METHODS: Eighty eyes of 40 patients were included in this study. All eyes underwent 2 or 3 sets of five measurements: before and after speculum placement, and after flap-lift (in LASIK cases). We assessed the reproducibility, accuracy, and the percentage of "no catch" measurements. The astigmatism was calculated pre-and 3-months-postoperatively by vector analysis. RESULTS: The mean age of the patients was 23.67 ・} 4.19 years. Preoperative spherical equivalent and astigmatism were -2.56 ・} 2.86 D and +1.36 ・} 0.98 D, respectively. The mean measurement time was 15.1 seconds per measurement. The percentages of "no catch" were: 63.8%, 14.9%, and 26.9%; pre-speculum, post-speculum, and post flap-lift, respectively. Cyclotorsion of ≥}2° was seen in 41.25% and 66% of the cases before and after the flap-lift, respectively. Significant cyclotorsion (≥}5°) was seen in 12.50% and 18% of the eyes pre and post flap-lift. The mean astigmatism dropped from +1.53 D@1° to +0.34D@3° when SCC was used and from +1.86D@1° to +0.23D@7° when SCC was not used. No statistical difference was noticed between the groups (p>0.05) in the postoperative residual astigmatism. A postoperative astigmatism of ≥ D was seen in 10% and 20% of eyes with and without SCC, respectively (p<0.01). CONCLUSION: Although not always feasible, the SCC measurement is a simple and useful tool. Postoperative astigmatism showed less variability when SCC was used.

Assessment of anterior and posterior corneal indices using two Scheimpflug analyzers.

PURPOSE: To assess the agreement between the elevation and curvature measurements of the anterior and posterior corneal surfaces obtained using the Galilei Dual Scheimpflug Analyzer and those obtained using the Pentacam single Scheimpflug system. METHODS: This prospective, noninterventional, diagnostic study was conducted at the Department of Ophthalmology at the American University of Beirut (Medical Center) and included 60 eyes of 60 consecutive patients. Measurements were obtained using 2 different Scheimpflug analyzers (Galilei and Pentacam). The best-fit sphere was set at 8 mm in both machines. Pachymetry (CCT), anterior elevation (AE) and posterior elevation (PE), and curvature were assessed. Pearson's correlation coefficients, comparison of means, and Bland-Altman plots were used to evaluate agreement between the 2 systems. RESULTS: The average CCT (at the corneal apex) was 533 ± 35 µm and 532 ± 37 µm (p=0.980), the average central AE was 1.25 ± 3.95 µm and 2.29 ± 5.28 µm (p=0.964), and the average central PE was 4.19 ± 8.18 µm and 5.42 ± 14.05 (p=0.956) µm with the Galilei and Pentacam, respectively. CONCLUSION: The Scheimpflug analyzers correlated well in the assessment of pachymetry, elevation, and curvature.

Delineation of LASIK flaps with prednisolone acetate eyedrops.

We describe the use and safety of prednisolone acetate eyedrops at the end of laser in situ keratomileusis (LASIK) to aid proper positioning of the corneal flap. The LASIK flap is created using the preferred technique. Following laser ablation and flap repositioning, one drop of prednisolone acetate is instilled on the eye. This delineates the flap "gutters" and allows perfect flap positioning and centration. We used this technique in 425 eyes undergoing LASIK for correction of spherocylindrical refractive errors. Flap margins were adequately delineated intraoperatively. The only complication related to the use of the steroid suspension was crystal deposition under the flap in one case which resolved completely in 48 hours.

Static cyclotorsion measurements using the Schwind Amaris laser / Medições da ciclotorção estática usando o laser Schwind Amaris

Purpose: To assess the reliability and reproducibility of static cyclotorsion correction (SCC) measurements made using the Schwind Amaris Excimer laser in patients undergoing LASIK or PRK, and compare the outcomes of treating astigmatism with and without SCC. Methods: Eighty eyes of 40 patients were included in this study. All eyes underwent 2 or 3 sets of five measurements: before and after speculum placement, and after flap-lift (in LASIK cases). We assessed the reproducibility, accuracy, and the percentage of "no catch" measurements. The astigmatism was calculated pre-and 3-months-postoperatively by vector analysis. Results: The mean age of the patients was 23.67 ± 4.19 years. Preoperative spherical equivalent and astigmatism were -2.56 ± 2.86 D and +1.36 ± 0.98 D, respectively. The mean measurement time was 15.1 seconds per measurement. The percentages of "no catch" were: 63.8%, 14.9%, and 26.9%; pre-speculum, post-speculum, and post flap-lift, respectively. Cyclotorsion of ≥±2º was seen in 41.25% and 66% of the cases before and after the flap-lift, respectively. Significant cyclotorsion (≥±5º) was seen in 12.50% and 18% of the eyes pre and post flap-lift. The mean astigmatism dropped from +1.53 D@1º to +0.34D@3º when SCC was used and from +1.86D@1º to +0.23D@7º when SCC was not used. No statistical difference was noticed between the groups (p>0.05) in the postoperative residual astigmatism. A postoperative astigmatism of ≥1 D was seen in 10% and 20% of eyes with and without SCC, respectively (p<0.01). Conclusion: Although not always feasible, the SCC measurement is a simple and useful tool. Postoperative astigmatism showed less variability when SCC was used. .

Objetivo: Avaliar a confiabilidade e reprodutibilidade da correção da medida de ciclotorção estática (SCC), realizada com o excimer laser Schwind Amaris em pacientes submetidos a LASIK ou PRK, e comparar os resultados do tratamento de astigmatismo com e sem SCC. Método: Oitenta olhos (40 pacientes). Todos os olhos foram submetidos a 2 ou 3 séries de 5 medições: antes e após a colocação do espéculo, e depois do levantamento do flap (nos casos de LASIK). Foram avaliadas a reprodutibilidade, a precisão e a porcentagem de medições "não obtidas". O astigmatismo foi avaliado no pré-operatório e aos 3 meses de pós-operatório, por meio de análise vetorial. Resultados: A idade foi 23,67 ± 4,19 anos. O equivalente esférico e o astigmatismo pré-operatórios foram -2,56 ± 2,86 D, e 1,36 ± 0,98 D, respectivamente. O tempo de medição médio foi 15,1 segundos por medição; as porcentagens de medidas "não obtidas" foram: 63,8%, 14,9% e 26,9%; pré, pós-espéculo, e pós-levantamento do flap, respectivamente. Ciclotorção ≥±2º foi observada em 41,25% e 66 % dos casos pré e pós-levantamento do flap. Ciclotorção significativa (≥±5º) foi observada em 12,50% e 18% pré e pós-levantamento do flap. A média do astigmatismo diminuiu de 1,53D @ 1º para 0,34D @ 3º quando SCC foi usado e de 1,86D @ 1º a 0,23D @7º quando SCC não foi usado. O astigmatismo residual pós-operatório não foi estatisticamente diferente entre os grupos (p>0,05). O astigmatismo pós-operatório ≥1D foi observado em 10% e 20 % dos olhos com e sem SCC, respectivamente (p<0,01). Conclusão: A medição do SCC é fácil e útil, apesar de nem sempre ...

Assessment of anterior and posterior corneal indices using two Scheimpflug analyzers / Índices da córnea anterior e posterior com dois analisadores Scheimpflug

Purpose: To assess the agreement between the elevation and curvature measurements of the anterior and posterior corneal surfaces obtained using the Galilei Dual Scheimpflug Analyzer and those obtained using the Pentacam single Scheimpflug system. Methods: This prospective, noninterventional, diagnostic study was conducted at the Department of Ophthalmology at the American University of Beirut (Medical Center) and included 60 eyes of 60 consecutive patients. Measurements were obtained using 2 different Scheimpflug analyzers (Galilei and Pentacam). The best-fit sphere was set at 8 mm in both machines. Pachymetry (CCT), anterior elevation (AE) and posterior elevation (PE), and curvature were assessed. Pearson's correlation coefficients, comparison of means, and Bland-Altman plots were used to evaluate agreement between the 2 systems. Results: The average CCT (at the corneal apex) was 533 ± 35 µm and 532 ± 37 µm (p=0.980), the average central AE was 1.25 ± 3.95 µm and 2.29 ± 5.28 µm (p=0.964), and the average central PE was 4.19 ± 8.18 µm and 5.42 ± 14.05 (p=0.956) µm with the Galilei and Pentacam, respectively. Conclusion: The Scheimpflug analyzers correlated well in the assessment of pachymetry, elevation, and curvature. .

Objetivo: Avaliar a concordância entre as medidas de elevação e curvatura das superfícies anterior e posterior da córnea obtidos pelos analisadores de Scheimpflug Galilei e Pentacam. Método: Estudo de teste diagnóstico, prospectivo, não-intervencional realizado no Departamento de Oftalmologia do Centro Médico da Universidade Americana de Beirute. Sessenta olhos de 60 pacientes consecutivos. As medições foram feitas usando dois analisadores Scheimpflug diferentes (Galilei e Pentacam). A esfera de melhor ajuste foi fixada em 8 mm para ambos equipamentos. Paquimetria (CCT), elevação anterior (AE) e elevação posterior (PE), e curvatura foram avaliados. Coeficientes de correlação de Pearson, comparação das médias, e gráficos de Bland-Altman foram utilizados para avaliar a correlação. Resultados: A média de CCT (no ápice da córnea) foi 533 ± 35 µm usando o Galilei e 532 ± 37 µm usando o Pentacam (p=0,980). As médias centrais de AE foram de 1,25 ± 3,95 µm e 2,29 ± e 5,28 µm com o Galilei e Pentacam, respectivamente (p=0,964). As médias de centrais de PE foram 4,19 ± 8,18 µm e 5,42 ± 14,05 µm com a Galilei e Pentacam, respectivamente (p=0,956). Conclusões: Os analisadores de Scheimpflug avaliados correlacionam bem em termos de paquimetria, elevação e curvatura. .

Intrastromal corneal ring segment SK for moderate to severe keratoconus: a case series.

PURPOSE: To report clinical results and safety profiles of symmetrical intrastromal corneal ring segment (ICRS; Intacs SK, Addition Technology Inc) implantation in eyes with moderate to severe keratoconus. METHODS: Interventional case series of 24 eyes from 22 patients implanted with Intacs SK using the femtosecond laser. Evaluation included uncorrected (UDVA) and corrected distance visual acuity (CDVA), manifest refraction, and Placido-based Scheimpflug imaging. Postoperative follow-up was 1 day, 1 week, and 1, 3, and 6 months. RESULTS: Mean patient age was 28±7 years (range: 16 to 41 years). All eyes had keratoconus. Twenty-one of 24 eyes had 2, 450-µm symmetrical segments inserted. Mean UDVA and CDVA were significantly better at 1, 3, and 6 months postoperatively (UDVA: 20/340 preoperatively vs 20/70 at 6 months [P<.001]; CDVA: 20/70 preoperatively vs 20/40 at 6 months [P<.001]; UDVA analysis of variance [ANOVA]: F=6.46, P=.0057; CDVA ANOVA: F=5.24, P=.0138). Pre- and 6-months postoperative clinical results were: mean spherical equivalent refractive error -9.60±4.86 diopters (D) and -3.05±2.05 D (P<.001), respectively; mean refractive cylinder, -3.20±1.50 D and -1.55±1.10 D, respectively (P<.001); and mean average total corneal power 52.03±4.49 D and 46.95±4.61 D, respectively (P<.001). No complications occurred, and no patients were lost to follow-up. Eyes with steeper preoperative corneal keratometry readings had the greatest flattening in corneal curvature and thus the greatest decrease in myopic refraction (r=-0.4, P<.001). No correlation was found between preoperative thinnest corneal pachymetry and postoperative curvature flattening. CONCLUSIONS: Implantation of Intacs SK for moderate to severe keratoconus is safe and effective, leading to significant decrease in myopia and appreciable decrease in astigmatism with improvement in CDVA.

Azithromycin 1.5% ophthalmic solution: efficacy and treatment modalities in chronic blepharitis.

PURPOSE: To assess the efficacy of topical 1.5% azithromycin in the treatment of moderate to severe chronic blepharitis and to compare the efficacy of two different treatment modalities. METHODS: A randomized clinical trial included 67 patients with chronic anterior and/or posterior blepharitis, followed-up for 3 months. Signs and symptoms were graded according to severity. Patients were randomized into two groups: 33 patients in group I and 34 patients in group II. Group I patients were treated with topical 1.5% azithromycin twice a day for three days, and Group II patients were treated with topical 1.5% azithromycin twice a day for three days then at bedtime for the rest of the month. All patients were instructed to apply warm compresses and an eye-friendly soap twice daily. RESULTS: Patients in both groups tolerated the treatment with minimal irritation. A significant improvement in signs and symptoms was noted at the one week follow-up visit. Group II showed a more pronounced and longer-lasting improvement that persisted after three months of follow-up. CONCLUSION: Topical 1.5% azithromycin ophthalmic solution is an effective treatment option for chronic blepharitis. In moderate to severe blepharitis, a one month treatment is safe and shows better improvement than the three-day protocol with no significant relapse until three months of follow-up.

MT1-MMP modulates bFGF-induced VEGF-A expression in corneal fibroblasts.

The cornea is physiologically avascular. Following a corneal injury, wound healing often proceeds without neovascularization (NV); however, corneal NV may be induced during wound healing in certain inflammatory, infectious, degenerative, and traumatic states. Such states disrupt the physiologic balance between pro-angiogenic and antiangiogenic mediators, favoring angiogenesis. Contributors to such states are matrix metalloproteinases (MMPs), which are key factors in both extracellular matrix remodeling and angiogenesis. Similarly, vascular endothelial growth factor A (VEGF-A) and basic fibroblast growth factor (bFGF) exert pro-angiogenic effects. Here, we elaborate on the facilitative role of MMPs-specifically Membrane Type 1 MMP (MT1-MMP, MMP14)-in corneal NV. Additionally, we provide new insight into the signaling relating to MT1-MMP, Ras, and ERK in the bFGF-induced VEGF-A expression pathways within the corneal fibroblasts.

Comparison of 2 types of intrastromal corneal ring segments for keratoconus.

PURPOSE: To assess the effectiveness and safety of 2 types of 6.0 mm intrastromal corneal ring segments (ICRS) in patients with mild to severe keratoconus. SETTING: Lebanese American University, Beirut, Lebanon. DESIGN: Retrospective comparative case series. METHODS: Eyes had implantation of Intacs SK ICRS (Group 1) or Keraring SI6 ICRS (Group 2). Visual acuity (logMAR), refraction, keratometry, and higher-order aberrations were compared 6 months and 1 year postoperatively. RESULTS: Group 1 comprised 66 eyes and Group 2, 107 eyes. The groups were comparable preoperatively. One-year postoperatively, the mean uncorrected distance visual acuity improved by 0.62 logMAR ± 0.19 (SD) in Group 1 and by 0.67 ± 0.17 logMAR in Group 2 (P=.211). The mean corrected distance visual acuity improved by 0.12 ± 0.11 logMAR and by 0.08 ± 0.13, respectively (P=.301). The spherical equivalent decreased by a mean of 2.80 ± 2.87 D and 2.65 ± 3.00 D, respectively (P=.572). Keratometry (K) flat and K steep decreased by a mean of 1.51 ± 1.57 D and 2.24 ± 1.61 D, respectively, in Group 1 and by 1.10 ± 2.00 D and 1.44 ± 1.64 D, respectively, in Group 2 (P=.667 and P=.184, respectively). Primary coma root mean square decreased by a mean of 1.09 ± 0.66 µm in Group 1 and 0.99 ± 0.72 µm in Group 2 (P=.716). CONCLUSION: Both ICRS models significantly improved visual function in patients with keratoconus, with comparable postoperative profiles and no major complications. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Azithromycin 1.5% ophthalmic solution: efficacy and treatment modalities in chronic blepharitis / Solução oftálmica de azitromicina 1,5%: eficácia e modalidades de tratamento em blefarite crônica

PURPOSE: To assess the efficacy of topical 1.5% azithromycin in the treatment of moderate to severe chronic blepharitis and to compare the efficacy of two different treatment modalities. METHODS: A randomized clinical trial included 67 patients with chronic anterior and/or posterior blepharitis, followed-up for 3 months. Signs and symptoms were graded according to severity. Patients were randomized into two groups: 33 patients in group I and 34 patients in group II. Group I patients were treated with topical 1.5% azithromycin twice a day for three days, and Group II patients were treated with topical 1.5% azithromycin twice a day for three days then at bedtime for the rest of the month. All patients were instructed to apply warm compresses and an eye-friendly soap twice daily. RESULTS: Patients in both groups tolerated the treatment with minimal irritation. A significant improvement in signs and symptoms was noted at the one week follow-up visit. Group II showed a more pronounced and longer-lasting improvement that persisted after three months of follow-up. CONCLUSION: Topical 1.5% azithromycin ophthalmic solution is an effective treatment option for chronic blepharitis. In moderate to severe blepharitis, a one month treatment is safe and shows better improvement than the three-day protocol with no significant relapse until three months of follow-up.

OBJETIVO: Avaliar a eficácia do uso tópico de azitromicina 1,5% no tratamento de blefarite crônica moderada a grave, comparando a eficácia de duas diferentes modalidades de tratamento. MÉTODOS: Um ensaio clínico randomizado incluiu 67 pacientes com blefarite anterior e/ou posterior crônica, acompanhados por três meses. Os sinais e sintomas foram classificados de acordo com a gravidade. Os pacientes foram randomizados em dois grupos: 33 pacientes no grupo I e 34 pacientes no grupo II. Os pacientes do grupo I foram tratados com azitromicina tópica 1,5% duas vezes ao dia durante três dias, e os pacientes do grupo II foram tratados com azitromicina tópica 1,5% duas vezes ao dia durante três dias e, em seguida, ao deitar, durante o resto do mês. Todos os pacientes foram instruídos a aplicarem compressas quentes e higiene palpebral duas vezes ao dia. RESULTADOS: Os pacientes em ambos os grupos toleraram o tratamento com irritação mínima. Melhora significativa dos sinais e sintomas foi observada na visita de uma semana de acompanhamento. Grupo II mostrou uma melhora mais acentuada e mais duradoura que persistiu após três meses de acompanhamento. CONCLUSÕES: A solução de azitromicina oftálmica tópica 1,5% é uma opção eficaz de tratamento para a blefarite crônica. Em blefarite moderada a grave, o tratamento de um mês é seguro e demonstrou melhora acentuada em relação ao protocolo de três dias, sem recidiva significante até três meses de acompanhamento.

Patient-perceived pain during laser in situ keratomileusis: comparison of fellow eyes.

PURPOSE: To compare pain scores during laser in situ keratomileusis (LASIK) between first-eye surgery and second-eye surgery. SETTING: Private practice, Beirut, Lebanon. DESIGN: Cohort study. METHODS: Sequential bilateral LASIK was performed between January 2010 and January 2011 by the same surgeon using a Schwind Amaris excimer laser. Hemodynamics and intraocular pressure (IOP) were monitored intraoperatively. Patients graded their pain perception on a 4-point scale after the completion of each eye's surgery. RESULTS: The study enrolled 154 patients. The first surgery was performed in the right eye in 106 patients and in the left eye in 48 patients. Patients reported discomfort during suction (mean pain score 0.80 ± 0.56 [SD]). More pain was reported during second-eye surgery by 74% of patients; 2% reported more pain in the first eye, and 24% reported equal pain in both eyes. The mean pain score was 0.63 ± 0.35 in the first eye and 0.93 ± 0.51 in the second eye (P=.01). Pain was higher during second-eye surgery whether the procedure was started in the right eye or in the left eye. Systolic blood pressure was also higher during second-eye surgery (P=.001). There was no statistically significant difference in diastolic blood pressure, heart rate, IOP, or suction-ring pressure. CONCLUSIONS: Patients had more pain during second-eye LASIK for reasons that are not clear. A psychological explanation or regional sensitization processes are potential factors and should be studied. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.