Silicone Oil and Intraocular Pressure: Unraveling the Post-Vitrectomy Relationship
Authors: Nikhila Meenakshi Ankem , Kumar M. Parni , Lavanya D. , Aravind A. Chaitanya , Srinivas A. , Srinivas A. Gita 
Published: March 2024

Aim of the Study: To assess the potential influence of silicone oil tamponade following vitrectomy on the early elevation of intraocular pressure (IOP), a critical factor associated with the emergence of secondary glaucoma in individuals with proliferative changes in the vitreous and retina.  Subjects and Methodology: This study was carried out in a prospective manner within the Department of Ophthalmology at Katuri Medical College and Hospital from January 2023 to January 2024, lasting for a duration of 1 year. The research involved 110 participants categorized into three groups based on their medical histories. The control cohort, comprising 40 patients, went through vitrectomy with either air or saline solution as a tamponade. The second group, consisting of 40 patients with retinal detachment and proliferative retinopathy changes, have undergone vitrectomy with silicone oil tamponade. The third group, comprising 30 patients diagnosed with diabetic retinopathy, underwent vitrectomy with silicone oil tamponade. This study encompassed the assessment of intraocular pressure’s (IOP) and gonioscopic findings one month before and after vitrectomy for all the participants. The primary focus of the analysis was the comparison of IOP values across the different groups.  Conclusion: The results indicated that there was no statistically notable contrast in intraocular pressure (IOP) values prior to and following the vitrectomy procedure within the control group (p=0.104). Additionally, there was no substantial difference in preoperative IOP values among the three groups of patients. However, a noteworthy distinction in IOP values was observed during one-month post-vitrectomy, particularly in patients who underwent silicone oil tamponade. This suggests that the use of silicone oil tamponade had a notable impact on intraocular pressure in these patients after the surgical procedure. The study observed that, a month Following vitrectomy, the mean intraocular pressure (IOP) values in individuals with silicone oil tamponade were notably elevated in comparison to the control group (p<0.05). However, when examining individuals with retinal detachment and individuals with diabetic retinopathy changes, did not exhibit a statistically notable variance in IOP one-month post-vitrectomy (p=0.331). Nevertheless, the qualitative examination exposed a 2 mmHg increase in intraocular pressure (IOP) in the diabetic retinopathy cohort. This study indicates that there exists no significant variance in angle width prior to and following vitrectomy among various groups included. Silicone oil in emulsified form was identified in 18% of the individuals with retinal detachment and in 17% of those with diabetic retinopathy, found in the chamber angle. Moreover, within the cohort of individuals with diabetic retinopathy, 10% of patients demonstrated this attribute of angle neovascularization one-month post-vitrectomy. The rise in intraocular pressure (IOP) in the initial postoperative phase can be linked to the introduction of silicone oil into the vitreous cavity following vitrectomy. The emulsification of silicone oil might be a factor in the early elevation of intraocular pressure (IOP), particularly in individuals with diabetes exhibiting angle neovascularization, potentially hastening the development of secondary glaucoma.