Advances in Corneal Surgical and Pharmacological Approaches to the Treatment of Presbyopia

Pharmacological treatments for the correction of presbyopia

Presbyopia affects between 1.7 and 2 billion people worldwide. Presbyopia significantly impacts productivity and quality of life in both developed and developing countries. During accommodation, the human eye changes its dioptric power by altering the shape of the lens, but the exact nature of this change has not been fully explained. Recently, topical treatments have been marketed for the treatment of presbyopia and others are under investigation. In order to prepare a review of these novel therapies, we searched the major biomedical search engines. We found 15 randomized clinical trials and 12 reviews that met our review criteria. There are two different strategies for this purpose, the pinhole effect that increases depth of focus and "crystalline lens relaxation" for which parasympathetic mimetics and lens oxidation intermediates have been used. The results are generally favorable in terms of improvement of near visual acuity, although the follow-up period of the studies is short. These are novel strategies in the early stages of research that could be useful in the treatment of presbyopia.

BCLA CLEAR Presbyopia: Evaluation and diagnosis

It is important to be able to measure the range of clear focus in clinical practice to advise on presbyopia correction techniques and to optimise the correction power. Both subjective and objective techniques are necessary: subjective techniques (such as patient reported outcome questionnaires and defocus curves) assess the impact of presbyopia on a patient and how the combination of residual objective accommodation and their natural DoF work for them; objective techniques (such as autorefraction, corneal topography and lens imaging) allow the clinician to understand how well a technique is working optically and whether it is the right choice or how adjustments can be made to optimise performance. Techniques to assess visual performance and adverse effects must be carefully conducted to gain a reliable end-point, considering the target size, contrast and illumination. Objective techniques are generally more reliable, can help to explain unexpected subjective results and imaging can be a powerful communication tool with patients. A clear diagnosis, excluding factors such as binocular vision issues or digital eye strain that can also cause similar symptoms, is critical for the patient to understand and adapt to presbyopia. Some corrective options are more permanent, such as implanted inlays / intraocular lenses or laser refractive surgery, so the optics can be trialled with contact lenses in advance (including differences between the eyes) to better communicate with the patient how the optics will work for them so they can make an informed choice.

Refractive Outcomes of Cataract Surgery in Patients With Intrastromal Femtosecond Laser Treatment of Presbyopia (INTRACOR)

PURPOSE

To evaluate the outcomes of cataract surgery with intraocular lens (IOL) implantation in patients who underwent intrastromal femtosecond laser treatment of presbyopia (INTRACOR).

METHODS

This was an interventional case series of 8 patients (10 eyes) who presented for cataract surgery 6.1 ± 3.2 years (mean ± standard deviation [SD]) after INTRACOR (Technolas Perfect Vision GmbH) treatment. A monofocal IOL was implanted in 9 eyes (7 patients) and a small-aperture IOL was implanted in 1 eye. The IOL power was calculated without adjustments using biometry obtained after the INTRACOR treatment. For additional calculations, keratometry obtained before the INTRACOR treatment was used. Postoperative examinations included visual acuity testing, manifest refraction, defocus curve, ocular biometry, corneal tomography, aberrometry, anterior segment optical coherence tomography, and slit-lamp examination.

RESULTS

After the cataract surgery, the mean ± SD uncorrected distance visual acuity was 0.37 ± 0.17 logMAR, the corrected distance visual acuity was 0.10 ± 0.10 logMAR, and the manifest refraction spherical equivalent, adjusted to infinity, was +0.39 ± 0.63 diopters (D). Intermediate and near visual acuity, both uncorrected and distance-corrected, and distance-corrected defocus curves varied considerably among patients. Using biometry performed after INTRACOR, the traditional IOL power calculation formulas produced hyperopic outcomes, with the mean ± SD prediction error ranging from +0.72 ± 0.34 to +0.96 ± 0.41 D. Although the mean ± SD prediction error decreased (range: -0.34 ± 0.56 to -0.15 ± 0.53 D) when using keratometry obtained before INTRACOR, the accuracy remained low due to high variability.

CONCLUSIONS

In patients with cataract who had previous INTRACOR treatment, IOL power calculation could be inaccurate, with a tendency toward hyperopic outcomes. These results require confirmation in more extensive studies. [J Refract Surg. 2023;39(10):676-682.].

Rotational stability and refractive outcomes of the DFT/DATx15 toric, extended depth of focus intraocular lens

PURPOSE

To quantitatively assess postoperative rotational stability and visual acuity with the DFT/DATx15 extended depth of focus (EDOF) toric intraocular lens (IOL).

METHODS

In this prospective case series, thirty-five patients with a calculated IOL power between + 15.0 D and + 25.0 D, corneal astigmatism between 0.75 D and 2.25 D, and no significant ocular pathology underwent cataract surgery. Primary outcome was rotational stability of the IOL at 1 month post-operatively. Secondary outcomes included residual refractive astigmatism, absolute residual astigmatism prediction error, and monocular distance and intermediate visual acuities.

RESULTS

Mean absolute postoperative IOL rotation was 1.1 ± 0.2 degrees, with no rotation of more than 3 degrees at the final visit. Monocular mean best spectacle-corrected distance visual acuity (BSCDVA) improved from logMAR 0.27 ± 0.030 to 0.078 ± 0.017 (P < .001). Monocular uncorrected distance visual acuity (UCDVA) improved from 0.93 ± 0.096 to 0.18 ± 0.022 (P < .001). Best spectacle-corrected intermediate visual acuity (DSCIVA) was 0.17 ± 0.025, and uncorrected intermediate visual acuity (UCIVA) was 0.27 ± 0.040. Residual regular astigmatic refractive error was 0.21 ± 0.047 D.

CONCLUSIONS

The toric DFT/DATx15 EDOF lens showed excellent rotational stability and effective and predictable correction of astigmatism. Its refractive outcomes and safety profile were similar to those identified in prior studies of the non-toric DFT/DAT015 EDOF IOL. A small difference in monocular BSCDVA, of uncertain clinical significance, was found when comparing these outcomes with prior DFT/DAT015 data. The trial was retrospectively registered on November 5, 2021 (TRN ​​NCT05119127).

Classification of Presbyopia by Severity

There are close to two billion individuals globally living with presbyopia. In spite of its ubiquitous and progressive nature, there is no widely accepted, formal guideline or consensus statement on the classification of presbyopia by degree of severity. A panel of leading eye care professionals representing both optometrists and ophthalmologists convened virtually to discuss and document their combined assessments from the body of literature and clinical practice expertise in this commentary. In light of emerging therapies, classifying presbyopia by mild, moderate, or advanced severity may help provide consistency of diagnosis among eye care providers and may aid in managing patient expectations with different treatment options.

Vision through Healthy Aging Eyes

As life expectancy grows, so too will the number of people adversely affected by age. Although it is acknowledged that many conditions and diseases are associated with age, this mini-review will present a current update of the various visual changes that generally occur in healthy individuals disregarding the possible effects of illness. These alterations influence how the world is perceived and in turn can affect efficiency or the ability to perform ordinary daily tasks such as driving or reading. The most common physical developments include a decreased pupil size and retinal luminance as well as changes both in intercellular and intracellular connections within the retina along the pathway to the visual cortex and within the visual cortex. The quantity and the physical location of retinal cells including photoreceptors, ganglion and bipolar retinal cells are modified. The clarity of intraocular organs, such as the intraocular lens, decreases. These all result in common visual manifestations that include reduced visual acuity, dry eyes, motility changes, a contraction of the visual field, presbyopia, reduced contrast sensitivity, slow dark adaptation, recovery from glare, variation in color vision and a decreased visual processing speed. Highlighting these prevalent issues as well as current and possible future innovations will assist providers to formulate treatments and thereby conserve maximum independence and mobility in the modern mature population.