Topical Insulin for Ocular Surface Disease

Background: Insulin and insulin-like growth factor (IGF)-1 receptors are present in ocular tissues such as corneal epithelium, keratocytes, and conjunctival cells. Insulin plays a crucial role in the growth, differentiation, and proliferation of corneal epithelial cells, as well as in wound healing processes in various tissues. Purpose: This review explores the potential role of topical insulin in the treatment of ocular surface diseases. Specifically, it examines its impact on corneal nerve regeneration, sub-basal plexus corneal nerves, and its application in conditions like corneal epithelial defects, dry eye disease, and diabetic keratopathy. Methods: The review analyzes studies conducted over the past decade that have investigated the use of topical insulin in ocular surface diseases. It focuses on indications, drug preparation methods, side effects, efficacy outcomes, and variations in insulin concentrations and dosages used. Results: While off-label use of topical insulin has shown promising results in refractory corneal epithelial defects, its efficacy in dry eye disease is yet to be demonstrated. Variations in concentrations, dilutions, and dosing guidelines have been reported. However, limited data on ocular penetration, ocular toxicity, and systemic side effects pose challenges to its widespread utility. Conclusion: This review synthesizes findings from ocular investigations on topical insulin to assess its potential applicability in treating ocular surface and corneal diseases. By highlighting indications, preparation methods, side effects, and efficacy outcomes, it aims to provide insights into the current status and future prospects of using topical insulin in ophthalmic practice.

Accuracy of 10 IOL power calculation formulas in 100 short eyes (≤ 22 mm)

BACKGROUND

To assess and compare the accuracy of 10 intraocular lens (IOL) power calculation formulas after cataract surgery in eyes with an axial length (AL) shorter than or equal to 22.00 mm.

METHODS

A retrospective case series included 100 eyes with an AL ≤ 22.00 mm that underwent uneventful cataract surgery. The refractive prediction error (PE) was calculated using 10 different IOL power calculation formulas: Barrett Universal II, EVO 2.0, Haigis, Hill RBF 2.0, Hoffer Q, Holladay 1 and 2, Kane, SRK/T and SuperLadas. The median absolute prediction error (MedAE ± SD) and mean absolute prediction error (MAE ± SD) were calculated after adjusting the mean prediction error (ME) to 0.

RESULTS

Hoffer Q obtained the lowest MedAE (0.292 D) after adjusting the ME to 0, followed very closely by EVO 2.0 (0.298 D) and Kane (0.300 D). EVO 2.0 and Kane obtained both the lowest MAE after adjusting the ME to 0 (0.386). Differences in MAE among the different formulas were not statistically significant (p > 0.05).

CONCLUSIONS

Our study reflects a tendency of the EVO 2.0 formula and the Kane formula along with the older Hoffer Q formula, to predict more accurately the refractive outcomes in short eyes that undergo cataract phacoemulsification surgery compared to the other formulas, despite this difference could not be statistically proved.

Undesirable High Astigmatism after Penetrating Keratoplasty in Pseudophakia Corrected with an Add-On Toric Intraocular Lens

The purpose of the present case is to report the visual outcomes of a pseudophakic patient with high post-penetrating keratoplasty astigmatism treated with implantation of toric AddOn® intraocular lens (IOL) in the sulcus. A 79-year-old man with a ophthalmologic history of pseudoexfoliative glaucoma and Fuchs endothelial dystrophy had a graft failure after Descemet's stripping automated endothelial keratoplasty procedure on his right eye. Consequently, a penetrating keratoplasty was performed, and a high corneal astigmatism of -9.8 D to 140° resulted in that eye after selective suture removal. A secondary AddOn® toric IOL customized for the patient with a manufacturer-calculated power of +11.0 D was implanted to 50° in sulcus of the right eye. Subjective refraction was used for IOL calculation. Final refraction was +1.0 D of sphere and -2.0 D of cylinder power to 105°, with spherical equivalent of 0.0 D. Best corrected visual acuity was logMAR 0.1 (20/25, 0.8 decimal) 1 year after the IOL implant. Our case report demonstrates that the toric AddOn® secondary IOL can be effective and safe in correcting residual refractive error of high regular astigmatism after keratoplasty in pseudophakic eyes.

The regression time of ocular surface squamous neoplasia using topical interferon alfa-2b does not depend on the initial tumor size

PURPOSE

The aim of this study was to determine if the initial tumor size correlates with the time to regression after topical interferon alfa-2b (1 million IU/mL) therapy in the treatment of ocular surface squamous neoplasia.

METHODS

A retrospective study was performed in 15 patients clinically diagnosed as having ocular surface squamous neoplasia and treated with topical interferon alfa-2b (1 million IU/mL, four times a day). All the cases of ocular surface squamous neoplasia included in the study had corneo-limbal involvement. The initial extension of the ocular surface squamous neoplasia was measured in square millimeters using the program ImageJ (LOCI, University of Wisconsin, Madison, USA) on images taken from the eyes of each patient immediately before the beginning of the treatment. The time until tumor resolution was measured for each case.

RESULTS

Complete tumor resolution was achieved in all the cases, with a mean initial tumor extension of 26.71 mm² (standard deviation ± 17.21 mm²) and a mean time until resolution of 77 days (standard deviation ± 32 days). An increased tumor volume after 15 days of treatment was obser ved in 2 patients, which completely resolved. No significant correlation was found between the time to resolution and the initial tumor extension measured in square millimeters (Spear man test, p=0.347).

CONCLUSIONS

Our study suggests that the duration of topical interferon alfa-2b treatment required does not depend on the initial tumor size of the ocular surface squamous neoplasia usually found in clinical practice.