Corneal surface wettability and tear film stability before and after scleral lens wear

Purpose: The aim of this study was to evaluate the anterior surface of scleral contact lens and ocular surface wettability before and after one-month of scleral lens wear in patients with keratoconus. Methods: Forty-nine patients with keratoconus (36.26 ± 9.03 years) were recruited. The sample was divided into two groups: patients with intrastromal corneal ring (KCICRS group) and patients without ICRS (KC group). TFSQ, Schirmer I test, Ocular Surface Disease Index (OSDI questionnaire), tear break-up time (TBUT) and corneal staining were evaluated in two different visits: Baseline (before lens wear) and one-month visit (10 min after lens removal). Visual Analog Scale (VAS questionnaire) was filled in just after inserting the lenses and just before removing them. TFSQ mean and inferior were evaluated over the contact lens surface at the moment of inserting the lens (baseline visit) and after 8 h of lens wear (one-month visit). Results: Anterior corneal surface TFSQ values increased in all groups after scleral lens wear (p  0.05). No changes were found in tear volume for total and in KC and KCICRS groups (p > 0.05). For all groups, there was a statistical decrease of TBUT (p < 0.05). In addition, OSDI score, corneal staining and VAS score improved after scleral lens wear from baseline in total and in both KC and KCICRS groups (p < 0.05). Conclusion: The scleral contact lens surface keeps its wettability after one-month of wear. However, the wettability of the ocular surface is worse after contact lens wearing

Repeatability of Aberrometry-Based Automated Subjective Refraction in Healthy and Keratoconus Subjects

Purpose. To compare the intersession repeatability of the Eye Refract, a new instrument to perform aberrometry-based automated subjective refraction, on healthy and keratoconus subjects. Materials and Methods. A cross-sectional and randomized study was performed. A total of 64 participants were evaluated in the study, selecting one eye per participant randomly. The sample was divided into two different groups: 33 healthy subjects (38.85 ± 13.21 years) and 31 with keratoconus (37.29 ± 11.37 years). Three refractions per participant with the Eye Refract were performed on three different days, without cycloplegia. The repeatability analysis of refractive variables (M, J0, and J45), binocular corrected distance visual acuity (BCDVA), and spent time in refraction was performed in terms of repeatability (Sr), its 95% confidence interval (r), and intraclass correlation coefficient (ICC). Results. There were no statistically significant differences (P ≥ 0.05) between sessions in both groups for all refractive variables (M, J0, and J45) and BCDVA. Spent time in refraction was reduced as the sessions went by (P < 0.05). The Eye Refract was more repeatable for refractive errors assessment in healthy subjects (M: Sr = 0.27 D; J0: Sr = 0.09 D; J45: Sr = 0.06 D) compared to those with keratoconus (M: Sr = 0.65 D; J0: Sr = 0.29 D; J45: Sr = 0.24 D), while it was similar for BCDVA. Conclusions. The Eye Refract offered better repeatability to assess refractive errors in healthy subjects compared to those with keratoconus. Despite measurements being also consistent in keratoconus subjects, they should be treated with caution in clinical practice

Accuracy and precision of automated subjective refraction in young hyperopes under cycloplegia

Purpose: To assess the agreement between the Eye Refract, an instrument to perform subjective automated refraction, and the traditional subjective refraction, as the gold standard, in young hyperopes under noncycloplegic and cycloplegic conditions. Methods: A cross-section and randomized study was carried out, involving 42 participants (18.2 ± 7.7 years, range 6 to 31 years). Only one eye was chosen for the analysis, randomly. An optometrist conducted the refraction with the Eye Refract, while another different optometrist conducted the traditional subjective refraction. Spherical equivalent (M), cylindrical components (J0 and J45), and corrected distance visual acuity (CDVA) were compared between both refraction methods under noncycloplegic and cycloplegic conditions. A Bland-Altman analysis was performed to assess the agreement (accuracy and precision) between both refraction methods. Results: Without cycloplegia, the Eye Refract showed significantly lower values of hyperopia than the traditional subjective refraction (p < 0.009), the mean difference (accuracy) and its 95% limits of agreement (precision) being -0.31 (+0.85, -1.47) D. Conversely, there were no statistical differences between both refraction methods under cycloplegic conditions (p ≥ 0.05). Regarding J0 and J45, both refraction methods manifested no significant differences between them under noncycloplegic and cycloplegic conditions (p ≥ 0.05). Finally, the Eye Refract significantly improved CDVA (0.04 ± 0.01 logMAR) compared with the traditional subjective refraction without cycloplegia (p = 0.01). Conclusions: The Eye Refract is presented as a useful instrument to determine the refractive error in young hyperopes, the use of cycloplegia being necessary to obtain accurate and precise spherical refraction.Depto. de Optometría y VisiónFac. de Óptica y OptometríaTRUEinpres

PhDAY 2020 -FOO (Facultad de Óptica y Optometría)

Por cuarto año consecutivo los doctorandos de la Facultad de Óptica y Optometría de la Universidad Complutense de Madrid cuentan con un congreso propio organizado por y para ellos, el 4º PhDAY- FOO. Se trata de un congreso gratuito abierto en la que estos jóvenes científicos podrán presentar sus investigaciones al resto de sus compañeros predoctorales y a toda la comunidad universitaria que quiera disfrutar de este evento. Apunta en tu agenda: el 15 de octubre de 2020. En esta ocasión será un Congreso On-line para evitar que la incertidumbre asociada a la pandemia Covid-19 pudiera condicionar su celebración

Anterior, Posterior, and Thickness Cornea Differences after Scleral Lens Wear in Post-LASIK Subjects for One Year

Submission received: 21 September 2023 / Revised: 2 November 2023 / Accepted: 3 November 2023 / Published: 8 November 2023The aim of this study is to analyze the anterior and posterior corneal surface shape and the corneal thickness difference outcomes between before and after scleral lens (ScCL) wear in post-LASIK ectasia subjects for one year. Twenty eyes with post-LASIK ectasia wearing scleral lenses were evaluated in a visit before contact lens and after 1, 6, and 12 months. The study variables analyzed included the apex, nasal, temporal, inferior, and superior corneal thickness; the anterior and posterior surface corneal at corneal diameters of 8, 6, 4, and 2 mm, and high-contrast visual acuity. A statistically significant increment of corneal thickness (p &lt; 0.05) was observed in the inferior area after 6 months and in the superior area in the 12-month follow-up after wearing ScCLs. The anterior corneal curvature presented a flattening and a statistically significant steepening (p &lt; 0.05) in the central and peripheral radii, respectively, after one year. The posterior corneal curvature showed a significant (p &lt; 0.05) steepening, which mainly affected the central region after one year. Despite these changes, high-contrast visual acuity with ScCL correction remained at the same values. The prolonged use of scleral lenses in post-LASIK subjects showed significant changes in the corneal curvature and thickness. These outcomes recommend more detailed and periodic topographic and vision quality checks to monitor the wear in ScCL patients.Depto. de Optometría y VisiónFac. de Óptica y OptometríaTRUEpu

A Comparison between Automated Subjective Refraction and Traditional Subjective Refraction in Keratoconus Patients

SIGNIFICANCE: The performance of the Eye Refract (Luneau Technology, Chartres, France), a new instrument to perform aberrometry-based automated subjective refraction, has been previously evaluated in healthy subjects. However, its clinical implications in other ocular conditions are still unknown. PURPOSE: The purpose of this study was to evaluate the agreement between the Eye Refract and the traditional subjective refraction, as the criterion standard, in keratoconus patients with and without intracorneal ring segments (ICRSs). METHODS: A total of 50 eyes of 50 keratoconus patients were evaluated, dividing the sample into 2 groups: 27 eyes without ICRS (37.78 ± 9.35 years) and 23 eyes with ICRS (39.26 ± 13.62 years). An optometrist conducted the refraction with the Eye Refract, and another different optometrist conducted the traditional subjective refraction on the same day. Spherical equivalent (M), cylindrical vectors (J0 and J45), and corrected distance visual acuity were compared between both methods of refraction. In addition, Bland-Altman analysis was performed to assess the agreement between both methods of refraction. RESULTS: There were no statistically significant differences (P ≥ .05) between the Eye Refract and the traditional subjective refraction for all the variables under study in either group. Without ICRS, the mean difference and 95% limits of agreement (upper, lower) were −0.20 (+1.50, −1.89) D for M, −0.14 (+1.40, −1.68) D for J0, and +0.05 (+1.23, −1.14) D for J45. With ICRS, these values worsened to −0.62 (+3.89, −5.12) D for M, +0.06 (+2.46, −2.34) D for J0, and −0.02 (+2.23, −2.28) D for J45. CONCLUSIONS: The Eye Refract seems to offer similar results compared with the traditional subjective refraction in keratoconus patients not implanted with ICRS. However, some patients could show abnormal measurements, especially those with ICRS, who should be treated with caution in clinical practice