Inherited retinal dystrophies are characterized by photoreceptor death. Oxidative stress usually occurs, increasing vision loss, and oxidative damage is often reported in retinitis pigmentosa (RP). More than 300 genes have been reported as RP causing. In contrast, choroidal neovascularization (CNV) only occasionally develops in the late stages of RP. We herein study the regulation of RP causative genes that are likely linked to CNV onset under oxidative conditions. We studied how the endogenous adduct N-retinylidene-N-retinylethanolamine (A2E) affects the expression of angiogenic markers in human retinal pigment epithelium (H-RPE) cells and a possible correlation with RP-causing genes. H-RPE cells were exposed to A2E and blue light for 3 and 6h. By transcriptome analysis, genes differentially expressed between A2E-treated cells and untreated ones were detected. The quantification of differential gene expression was performed by the Limma R package. Enrichment pathway analysis by the FunRich tool and gene prioritization by ToppGene allowed us to identify dysregulated genes involved in angiogenesis and linked to RP development. Two RP causative genes, AHR and ROM1, can be associated with an increased risk of CNV development. Genetic analysis of RP patients affected by CNV will confirm this hypothesis.

Purpose: Dexamethasone and other corticosteroids are administered intravitreally to treat a variety of retinal diseases. As a side effect, they can alter intraocular pressure (IOP). The purpose of this study is to describe the incidence, severity, and management of ocular hypertension following the administration of multiple intravitreal injections of dexamethasone implants. Materials and Methods: A total of 78 eyes of 78 subjects (males 62%; females 38%; mean age 67 ± 13 years SD) received a total of 152 intravitreal injections of 0.7 mg dexamethasone implants over 4 years. Indications included retinal vein occlusion (87%), diabetic macular edema (9%), wet-type age-related macular degeneration (4%). Ocular hypertension was defined as intraocular pressure above 23 mmHg or any pressure increase of 10 mmHg or more from baseline values. IOP was measured by applanation tonometry before the injection (T0), as well as one week (T1), one month (T2), and three months (T3) afterwards. Results: Five percent (4/78) of subjects developed ocular hypertension after the 1st injection. On the second and third rounds, additional 7.2% (3/42) and 4.2% (1/24) of subjects developed the same side effect. Among the 8 subjects who received a fourth injection, none was found with OHT. Pressure elevations were detected at T2 and T3. In all patients, topical medical therapy was sufficient to lower the IOP below threshold. Mean pressure variations following the first injection as compared to previous recorded values were +0.97 mmHg (T1), +0.92 mmHg (T2), and − 0.41 mmHg (T3) (p < 0.05). Mean pressure variations following the second injection were +0.54 mmHg (T1), +0.23 mmHg (T2) and − 0.66 mmHg (T3) (p < 0.05). Conclusion: Ocular hypertension is a recognized side effect of intravitreal dexamethasone. Some patients develop it right after the first injection, while others develop it subsequently, on the 2nd or 3rd round. This side effect becomes most apparent 30– 90 days following the implantation procedure and responds well to topical pressure-lowering medications.

Purpose: Stargardt disease (STGD1) is the most common hereditary macular degeneration and currently no treatments have been approved to interrupt the progression of the disease. The aim of this study was to evaluate the efficacy of photo-biomodulation in patients with Stargardt disease 1 year after treatment, considering as primary outcomes improvements in best corrected visual acuity (BCVA), microperimetry, and pattern electroretinography (PERG) amplitude. Materials and Methods: Ninety eyes of 45 patients with a diagnosis of Stargardt disease stage 1 were prospectively recruited at the University of Bologna. Selected patients were treated with photo-biomodulation therapy for 1 year for 10 minutes a day, twice a day, and 5 days per week for 12 months. A light emitting diode (LED) of 10 Hz and wavelength 650 nm was used. BCVA and microperimetry were assessed before treatment and 1 year after photo-biomodulation, whereas PERG was assessed at baseline, 1, 3, 6, and 12 months after treatment. Results: BCVA improved from 0.7 [interquartile range (IQR)=0.6– 0.9)] to 0.4 (IQR=0.2– 0.5)] after treatment (95% CI=− 0.3, − 0.35; p=< 0.001) and PERG negative wave at 35 ms (N35)-positive wave at 50 ms (P50) amplitude improved from 0.9 (IQR=0.74– 1.21) to 2.12 (95% CI=1.11, 1.28; p< 0.001). MP-1 Microperimetry improved from 26.5% (IQR=16.75– 40) of median preferred retinal loci (PRL) within an area of 2° of diameter to 38% (IQR=29– 50.25; 95% CI=10.50, 14.50; p=< 0.001); on the other hand, PRL within 4° of diameter raised from 72% (IQR=51.5– 80) to 80% (IQR=76– 87) after photo-biomodulation (95% CI=4.50, 7.50; p< 0.001). Also, patients with an improvement of more than 1.205 PERG N35-P50 ratio amplitude at 3 months and more than 1.29 at 6 months tended to present an improvement of more than 0.2 logMar in BCVA at 12 months (p=0.28, AUC=0.630; p=0.30, AUC=0.636). Conclusion: BCVA, PERG, and MP-1 significantly improved 1 year after treatment. Also, improvement of PERG N35-P50 amplitude at 3 and 6 months was correlated to BCVA improvement at 1 year, suggesting that PERG could be useful in predicting visual outcome after photo-biomodulation.

Purpose: To assess and contrast the visual and refractive results of Descemetic deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in the treatment of advanced keratoconus. Design: Retrospective, comparative, interventional study. Methods: This study enrolled eyes affected by keratoconus with preoperative mean keratometry ≥ 60 diopters (D) that were treated with either Descemetic DALK (30 eyes) or PK (29 eyes) by using always the same corneal diameters (8.00mm recipient; 8.25mm donor cornea) and the same suture technique (10– 0 nylon double-running 12-bites continuous suture). The outcome measures were postoperative uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (CDVA), subjective refractive astigmatism (SRAst), and keratometric astigmatism at 3mm area (SimK), spherical equivalent (SEq). Results: Postoperative visual acuity significantly improved in both groups. Mean CDVA was higher in the DALK group 3 months (DALK 0.61, PK 0.42, p< 0.05), 6 months (DALK 0.69, PK 0.44, p< 0.05), and 12 months (DALK 0.72, PK 0.45, p< 0.05) postoperatively. However, 6 months after suture removal, CDVA was not statistically different between the two groups (DALK 0.71, PK 0.75, p> 0.05). Final SRAst and SimK also were comparable between the two groups (respectively DALK 2.97, PK:2.81, p> 0.05; DALK 3.91, PK 2.37, p> 0.05). No significant statistical differences were noted for UCVA and SEq data during the entire follow-up period between the two groups. Conclusion: Both methods of corneal transplantation resulted in a notable enhancement of visual and refractive outcomes in eyes afflicted by advanced keratoconus. Descemetic DALK demonstrated superior visual acuity before suture removal, whereas DALK and PK exhibited comparable results in terms of visual acuity, refractive correction, and keratometric astigmatism after suture removal.

Purpose: To evaluate visual and refractive outcomes of customized photorefractive keratectomy (PRK) in subjects with persistent subepithelial corneal opacities secondary to adenoviral epidemic keratoconjunctivitis (EKC). Patients and Methods: Prospective study, which recruited patients with persistent and visually-significant post-EKC corneal opacities unresponsive to prolonged topical therapy (6 months or more). Outcome measures: uncorrected and best-corrected distance visual acuity, subjective refractive astigmatism, keratometric astigmatism, spherical equivalent, minimum corneal thickness, and corneal morphological irregularity index. Subjects were followed for 12 months post-treatment. Results: Eighteen eyes of 18 patients aged between 32 and 75 years treated with topography-guided transepithelial PRK with iRes excimer laser (iVIS Technologies, Taranto, Italy) from June 2020 to July 2021. After 12 months, the mean UDVA improved from 1.0± 0.00LogMAR pre-op to 0.15± 0.154LogMAR, and the mean CDVA improved from 0.4± 0.41LogMAR pre-op to 0.0± 0.00LogMAR. With respect to UDVA, all treated eyes (100%) showed an improvement of 6 ETDRS lines or more and with respect to CDVA, 9 out of 18 eyes (50%) showed an improvement of 6 ETDRS lines or more. The mean ablation depth was 54.7± 5.9μm. A statistically significant improvement was observed in all topographic indices. No infiltrate recurrence, post-treatment corneal haze, ocular hypertension or other side effects were observed throughout the follow-up period. Conclusion: Topography-guided PRK could be considered an effective and safe treatment option to improve visual acuity in patients affected by persistent and visually-significant subepithelial corneal infiltrates caused by EKC.