Increased Straylight in Patients With Keratoconjunctivitis Sicca

Intraocular Straylight and Multifocal Soft Contact Lens Fit With a Myopia Control Approach

OBJECTIVES

Center-distance multifocal contact lenses (MFCLs) are used to slow myopia progression. We examined the effect of two MFCLs on intraocular straylight values in myopic individuals.

METHODS

Twenty-five young myopic adults were enrolled and were fit with three contact lenses (Biofinity sphere, Biofinity Multifocal, and NaturalVue Multifocal) in a random order over two study visits. Pupil size (NeurOptics VIP-300, Laguna Hills, CA) and contact lens centration were measured. Right eye intraocular straylight measurements were collected (OCULUS C-Quant; Wetzlar, Germany) and compared with a spectacle trial lens. Log straylight (LogSL) values and straylight residuals were analyzed using repeated-measures analyses of variance with Tukey-corrected post hoc t -tests.

RESULTS

The mean participant age (±SD) was 24.1±1.5 years, and right eye spherical equivalent refractive error was -3.38±1.53 DS. There was no difference in mesopic pupil size between visits ( P =0.68) and no difference in contact lens centration between lenses ( P =0.99). LogSL values differed by lens type ( P =0.004). LogSL with the spectacle trial lens was significantly greater than with each contact lens type (all P <0.05), but there were no significant differences in LogSL between the three contact lenses (all P >0.05). There was no difference between the three contact lens designs for straylight residuals ( P =0.33).

CONCLUSIONS

Measured intraocular straylight for both MFCLs was not different than with a spherical soft contact lens. A significant increase in intraocular straylight with spectacle trial lens correction was observed compared with all contact lenses.

Vitreous and Vision Degrading Myodesopsia

Macromolecules comprise only 2% of vitreous, yet are responsible for its gel state, transparency, and physiologic function(s) within the eye. Myopia and aging alter collagen and hyaluronan association causing concurrent gel liquefaction and fibrous degeneration. The resulting vitreous opacities and collapse of the vitreous body during posterior vitreous detachment are the most common causes for the visual phenomenon of vitreous floaters. Previously considered innocuous, the vitreous opacities that cause floaters sometimes impact vision by profoundly degrading contrast sensitivity function and impairing quality-of-life. While many people adapt to vitreous floaters, clinically significant cases can be diagnosed with Vision Degrading Myodesopsia based upon echographic assessment of vitreous structure and by measuring contrast sensitivity function. Perhaps due to the ubiquity of floaters, the medical profession has to date largely ignored the plight of those with Vision Degrading Myodesopsia. Improved diagnostics will enable better disease staging and more accurate identification of severe cases that merit therapy. YAG laser treatments may occasionally be slightly effective, but vitrectomy is currently the definitive cure. Future developments will usher in more informative diagnostic approaches as well as safer and more effective therapeutic strategies. Improved laser treatments, new pharmacotherapies, and possibly non-invasive optical corrections are exciting new approaches to pursue. Ultimately, enhanced understanding of the underlying pathogenesis of Vision Degrading Myodesopsia should result in prevention, the ultimate goal of modern Medicine.

Clinical features and visual function in a patient with Fish-eye disease: Quantitative measurements and optical coherence tomography

Purpose

We describe a case of fish-eye disease (FED) where the clinical features and visual function were investigated using anterior segment optical coherence tomography (OCT) and quantitative measurements.

Observations

A 36-year-old Japanese woman with FED presented with bilateral corneal opacities and visual complaints. Both contrast sensitivity and straylight were measured and OCT imaging was performed. Contrast sensitivity and straylight measurements revealed remarkably decreased visual function, despite good visual acuity. OCT demonstrated homogenously hyper-reflective corneal opacification, and a normal total corneal thickness.

Conclusions and Importance

The findings from this case suggest that OCT is useful for analyzing the clinical features of FED, and that the quantitative measurement of visual function furthers the understanding of vision-related symptoms in FED, despite good visual acuity.

Mechanisms of Visual Disturbance in Dry Eye

Dry eye has been believed to be a chronic, symptomatic ocular surface disease that affects vision in a limited manner, because it is difficult to detect visual or optical changes using standard visual acuity testing. In practice, common visual complaints associated with dry eye include fluctuating vision with blinking, blurred vision, glare, and eye fatigue. This review discusses our past and current understanding of visual disturbances in dry eye and the various tools available for assessing visual function or optical quality. Tear film instability and ocular surface damage are key factors in the core mechanism underlying dry eye. The mechanisms of these vision-related subjective symptoms of dry eye based on visual function, particularly wavefront aberrations or light scattering, and the core mechanism of dry eye are described. Tear film instability is associated with decreased stability of postblink higher-order aberrations, leading to "fluctuating vision with blinking" and with increased ocular forward light scattering, leading to "glare." Ocular surface damage in the overlying optical zone (in the central corneal regions), is associated with increased higher-order aberrations and increased corneal backward light scattering that can lead to "blurred vision". "Eye fatigue" occurs when patients with dry eye struggle to see things under such visual symptoms.

Comparison of 0.2% and 0.18% hyaluronate eye drops in patients with moderate to severe dry eye with keratitis or keratoconjunctivitis

PURPOSE

Comparison of efficacy and safety of 0.2% and 0.18% hyaluronic acid (HA) eye drops three times a day (tid) in patients with moderate to severe dry eye disease, related to keratitis or keratoconjunctivitis.

PATIENTS AND METHODS

Prospective, multicenter, randomized, single-masked, phase IIIb, noninferiority study (0.2% HA vs 0.18% HA) in two parallel groups over a period of 84 days. N=70 patients were evaluated. Primary efficacy outcome was ocular surface (OS) staining change on day 35 (D35), compared to baseline. Fluorescein and lissamine green were used for staining of cornea and conjunctiva. Secondary efficacy outcome included tear film breakup time, OS staining score on day 84 (D84), ocular comfort index, as well as patients' and doctors' evaluation.

RESULTS

Compared to day 0 (D0), 0.2% HA achieved a 47.7% reduction in staining score (-3.00±2.81 [standard deviation] points, n=38 patients) at D35; 0.18% HA showed a 41.2% reduction (-2.59±2.20 [standard deviation] points, n=32 patients). Statistical analysis showed noninferiority in efficacy of 0.2% HA compared to 0.18% HA on D35. At D84, the reduction in staining score had further increased to 64.5% for 0.2% HA and to 56.4% for 0.18% HA. Both eye drops improved tear film breakup time and ocular comfort index values. Investigators and patients assessed both treatments with 5 of 7 points (Likert Scale, medians). The rate of adverse events (AE) was 2.3% for 0.2% HA and 7.1% for 0.18% HA with no serious AE.

CONCLUSION

0.2% and 0.18% HA eye drops significantly improved signs and symptoms of dry eye disease and were well tolerated with few AEs. Noninferiority of 0.2% HA compared to 0.18% HA was demonstrated for reduction of OS lesions. In some parameters, there was a nonsignificant trend in favor of 0.2% HA concentration.