"Comparing Methotrexate Usage Techniques to Prevent Proliferative Vitreoretinopaty After Retinal Detachment Vitrectomy"

This interventional trial will be conducted at the Sahiwal Teaching Hospital, Sahiwal and Ali Fatima Teaching Hospital Lahore from March 2024 to May 2025. The study will follow the guidelines of the Declaration of Helsinki. The study protocol will be approved by institutional review boards of respective hospitals. Written informed consent will be taken from all the subjects. The first subject will be recruited in March 2024 and the last subject will be recruited in February 2025. Three more months will be required to complete the final follow-up of the last subject.

The study will include rhegmatogenous retinal detachments patients of both sexes between 20 and 70 years of age.

Exclusion criteria will include the presence of proliferative vitreoretinopathy grade C, previous retinal detachment surgery in the same eye, penetrating ocular trauma, intraocular foreign bodies, and pregnant and lactating women.

A detailed history of the patients' presenting complaints, duration of symptoms, and risk factors for retinal detachment will be gathered. Comprehensive ocular examination, including visual acuity, intraocular pressure, and examination of the anterior and posterior segments, will be performed. The extent of retinal detachment, location of retinal breaks, and presence of PVR will be documented.

Sampling method will be simple random sampling. Using lottery methods patients will be divided into two groups with 60 subjects in each group. Group 1 will be regarded as control group and per operative methotrexate infusion will be used by mixing 75 mg of methotrexate into one litre of BSS solution. Group 2 will be regarded as the study group and will receive 500 µg of intra-silicon oil methotrexate at the end of the surgery and then at 1st, 2nd, 3rd , 4th and 6th post operative weeks.

This will be a single-blind study in which the subjects will be unaware of the intervention. Blinding will be maintained by ensuring that subjects are unaware of the dosing regimens they are receiving.

Standard pars plana vitrectomy will be performed by two surgeons, one surgeon at Sahiwal Teaching Hospital Sahiwal and other surgeon at Ali Fatima Teaching Hospital Lahore. Silicon oil will be used as post operative tamponade in all subjects. A combination of steroid and antibiotic eye drops will be administered eight times per day during the first postoperative week. The dosing will be tapered off during the next three weeks. Patients will be instructed to adopt the appropriate posture according to the location of retinal breaks.

Follow-up will be performed every week for three months. The development of PVR, occurrence of retinal detachment, intraocular pressure, and visual acuity will be noted. The posterior segment will be examined with the help of a superfield lens and wide-field contact lens for the development of PVR and occurrence of retinal detachment.

The primary outcomes will be the development of PVR and the recurrence of retinal detachment. All patients will be followed up until the development of one of the primary outcomes or completion of 3 month follow, whichever occurs earlier.

Improvement in visual acuity will be secondary outcome of the study. Final visual acuity will be measured at completion of 3 month follow up or meeting the primary outcome, whichever is earlier.

All information will be collected using a specially designed proforma and entered into SPSS version 26. Qualitative variables, such as sex, PVR development, recurrence of retinal detachment, and improvement in visual acuity, will be presented as frequencies and percentages. Quantitative variables, such as age and intraocular pressure, are presented as mean and standard deviation.

In this prospective study we shall investigate the differences in the development of proliferative vitreoretinopathy (PVR) between two distinct groups. Additionally, we shall compare the difference in the occurrence of re-detachment of the retina between these groups. Furthermore, we shall compare the improvement in visual acuity at the final follow-up visit between the two groups. As the variables involved will be qualitative (frequency of eyes with development of PVR, Frequency of eyes with retinal re-detachment, and frequency of eyes with improved visual acuity), Pearson's chi-square test will be used to carry out the statistical analysis. Statistical significance will set at P ≤ 0.05.