Current Developments in the Management of Amblyopia with the Use of Perceptual Learning Techniques

Background and Objectives: Amblyopia is a neurodevelopmental disorder caused by interocular suppression of visual input, affecting visual acuity, stereopsis, contrast sensitivity, and other visual functions. Conventional treatment comprises occlusion of the sound eye. In recent years, novel therapies that deploy perceptual learning (PL) principles have been introduced. The purpose of this study is to assess the latest scientific data on this topic. Materials and Methods: For this purpose, we conducted a literature search for relevant studies published during the previous 4 years (2020-2023). Results: A plethora of visual perceptual learning protocols have been recently developed. Dichoptic video games, contrast rebalanced movies, and online perceptual training platforms are the main formats. Perceptual learning activates neuroplasticity, overcomes interocular suppression, and improves the visual impairments induced by amblyopia. Conclusions: This novel treatment is effective in both children and adults, as well as in patients non-responding to patching.

Branch Retinal Vein Occlusion as a Rare Presentation of Antisynthetase Syndrome

A 52-year-old woman developed branch retinal vein occlusion (BRVO) in her right eye, resulting in blurred vision with visual acuities of 6/9 and 6/6-2 in the affected and unaffected eye respectively (Snellen). The patient was successfully treated with a course of eight intravitreal aflibercept injections, improving binocular visual acuity to 6/6. During the course of her ocular management, she was admitted for acute dyspnoea secondary to interstitial lung disease (ILD). The patient was diagnosed with the antisynthetase syndrome (ASS), testing positive for PL-7 auto-antibodies. ASS may have a systemic association with BRVO; although ASS is a rare condition, it should be suspected and investigated in patients with risk factors, particularly if they present with symptoms of ILD. Early ocular intervention is associated with excellent visual outcomes, and prompt diagnosis and treatment of ASS may potentially reduce risks of further retinal vaso-occlusive episodes.

Impact of lens density and lens thickness on cumulative dissipated energy in femtosecond laser-assisted cataract surgery

To evaluate the required cumulative dissipated energy (CDE) to fragment the crystalline lens in femtosecond laser-assisted cataract surgery (FLACS) in relation to lens density and lens thickness. Consecutive eyes that underwent FLACS between September 2014 and March 2017 by a single surgeon using in all cases the same femtosecond laser and phacoemulsification platform were included in our retrospective study. Prior to surgery, corrected distance visual acuity (CDVA), optical biometry corneal, and crystalline lens tomographies were performed to assess anterior chamber depth (ACD), axial length (AL), and crystalline lens parameters (i.e., lens density, thickness, and nucleus staging (NS)). After surgery, CDE was calculated and analyzed in relation to lens density (LD) and lens thickness (LT). Zero ultrasound expenditure cases were recorded and their occurrence analyzed. The chart review identified 236 eyes of 200 patients, 98 males and 102 females aged 65± 15 years which were included in the study. Mean LD was 11.26 ± 2.05 pixel intensity units (range 7.30-18.80), and the mean LT was 3417 ± 405.17 μm (range 2545-4701). LD and LT correlated moderately (r = 0.50, p < 0.001) and weakly (r = 0.23, p < 0.001), with post-laser CDE. Higher LD and LT were also associated with lower rates of zero phaco (eyes in which no phacoemulsification energy was necessary). Furthermore, NS (r = 0.528, p < 0.001) and CDVA (r = - 0.3524, p < 0.001) also correlated with CDE. Higher LD, LT, NS values, and low CDVA are associated with higher ultrasound expenditure (CDE-cumulative dissipated energy) and with lower rates of zero ultrasound expenditure during FLACS.

Corneal, Scleral, Choroidal, and Foveal Thickness in Patients with Rheumatoid Arthritis

Objectives:

To investigate corneal, scleral, choroidal, and foveal thicknesses in female patients with rheumatoid arthritis (RA) and compare them with healthy subjects.

Materials and Methods:

This prospective study included consecutive female patients diagnosed with RA and healthy subjects. Corneal, scleral, choroidal, and retinal (foveal) thicknesses were obtained by using optical coherence tomography and a comparison was performed between groups for all outcome measures.

Results:

Thirty-six eyes of 36 female patients diagnosed with RA (group 1) and 36 eyes of 36 healthy female volunteers (group 2) were included. Mean corneal, scleral, choroidal thicknesses and retinal thickness at the fovea of group 1 were 543.3±33.7 µm, 343.7±42.2 µm, 214.6±50, and 213.5±18.9 µm, respectively; in group 2, these values were 549.9±29.6 μm, 420.9±42.4 μm, 206.4±41.9 μm, and 222±15.5 μm, respectively. The comparison between group 1 and 2 with respect to corneal, choroidal, and foveal thicknesses did not reveal statistical significant differences (p>0.05). On the contrary, there was a statistically significant difference with respect to scleral thickness between the groups, with the RA patients demonstrating a thinner scleral layer (p<0.001).

Conclusion:

Female patients with RA seem to demonstrate statistically significant scleral thinning when compared with healthy subjects, while there was no difference concerning corneal, choroidal, and foveal thickness.

Long-term results of thin corneas after refractive laser surgery

PURPOSE

To report the long-term refractive results of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in patients with thin corneas.

DESIGN

A long-term, retrospective, non-randomized follow-up study.

METHODS

Sixty-three patients (124 eyes) (28 males and 35 females), who had a preoperative central corneal thickness (CCT) of less than 500 microns and completed at least one year of follow-up examinations after surgery. Thirty-five patients (68 eyes) underwent PRK and 28 patients (56 eyes) underwent LASIK.

RESULTS

Mean preoperative corneal pachymetry was 484.95 +/- 6.65 microm (range, 470 to 498 microm) and 482.38 +/- 10.73 microm (range, 453 to 499 microm) for LASIK and PRK, respectively. No intraoperative complications were found in both groups. None of the included eyes developed postrefractive corneal ectasia. The mean predictability for the PRK group was 0.08 diopters (D) with a standard deviation of 0.40 D (range, -1.38 to 1.00 D), and the mean predictability for the LASIK group was 0.14 D with a standard deviation of 0.55 D (range, -1.25 to 1.33 D).

CONCLUSIONS

Refractive laser surgery with LASIK or PRK in patients with thin corneas (less than 500 microm) seems to be a safe and predictable technique for myopic refractive corrections.