Effect of Single Incision Versus Three Planned Incisions to Reduce Pre-operative Astigmatism After Phacoemulsification.

Effect of Single Incision Versus Three Planned Incisions to Reduce Pre-operative Astigmatism After Phacoemulsification.

Effect of Single Incision Versus Three Planned Incision to Reduce Pre-operative Astigmatism After Phacoemulsification.

Cataract surgery by phacoemulsification is the most commonly performed procedure in Pakistan. Cataract surgery aims for visual rehabilitation and freedom from all kinds of eyewear. Pre-operative corneal astigmatism greater than 1.0 Diopter is reported in 42% preoperatively and 58%postoperatively after implanting a monofocal intraocular lens(IOL). Visual acuity tended to worsen postoperatively with increased astigmatism4. Different treatment modalities are used to reduce astigmatism, like toric IOL. Limbal relaxing incision, actuate keratotomy, intrastromal rings, Lasik and femtosecond laser. Most of these modalities are expensive, so they cannot be afforded by the patients as Pakistan is a low-income country with a per capita income of US$1,562 (160th worldwide)

According to the 2020 estimate, 33·6 million adults aged 50 years and older were blind with cataracts as a leading cause (15·2 million cases). According to Pakistan national blindness survey, cataract is the leading cause of blindness in Pakistan. Cataract surgery by phacoemulsification is the most commonly performed procedure in Pakistan. Cataract surgery aims for visual rehabilitation and freedom from all kinds of eyewear. Pre-operative corneal astigmatism greater than 1.0 Diopter is reported in 42% preoperatively and 58%postoperatively after implanting a mono-focal intraocular lens(IOL). Visual acuity tended to worsen postoperatively with increased astigmatism. Different treatment modalities are used to reduce astigmatism, like toric IOL. Limbal relaxing incision, actuate keratotomy, intrastromal rings, Lasik and femtosecond laser. Most of these modalities are expensive, so they cannot be afforded by the patients as Pakistan is a low-income country with a per capita income of US$1,562 (160th worldwide). Our study aims to compare the results of phacoemulsification cataract surgery with a planned three (one 2.8 mm and two 2.0mm) on the or near to steep meridian incisions ( group A) with convention supero-temporal 2.8 mm clear corneal incision(Group B) for the correction of postoperative astigmatism. We hypothesize that a planned three (one 2.8 mm and two 2.0mm) on the or near to steep meridian incisions ( group A) is better than conventional supero-temporal 2.8 mm clear corneal incision(Group B) for the correction of postoperative astigmatism at a significant level of 0.05.

The patient will be selected and randomized into two groups after obtaining informed consent. patient will not know about the intervention

Planned three (one 2.8 mm and two 2.0mm) on the or near to steep meridian will be performed in the experimental group during phacoemulsification

Patients will be assessed at first postoperative day then after one month , three months and six months.

Inclusion Criteria: Cataract patients aged between 50 and 80 years having 1.0 diopters (D) or greater of regular corneal astigmatism documented by keratometry. Exclusion Criteria: 1. Previous ocular surgery. 2. previous ocular trauma. 3. Pre-existing ocular disease. 4. High intraocular pressure (IOP) 5. Corneal opacity. 6. Strabismus 7. Amblyopia 8. Diabetes mellitus 9. Irregular astigmatism. -

the clinical study report will be shared with all participants if they desire. the study will be published in a journal. it will be available to all participants and the research community.

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