ABSTRACT
Objectives: To determine the efficacy and safety of Optic Nerve Sheath Fenestration (ONSF) for salvaging acutely threatened vision in patients of Idiopathic Intracranial Hypertension (IIH). Methods: This retrospective, interventional case series study was performed at Institute of Ophthalmology Mayo Hospital Lahore from September 2017 to September 2019. Nine patients diagnosed with Idiopathic Intracranial Hypertension as per Modified Dandy Criteria, underwent medial trans-conjunctival ONSF. Pre-operative and 1st day, 1st week, 1st month, 1st year, and 2nd year postoperative best-corrected logMAR visual acuities (BCVA) were recorded. Mean BCVA were calculated and compared using paired t-test. P-value <0.05 was taken as significant. Results: All nine patients were female with a mean age of 24 years. The average best-corrected pre-operative logMAR visual acuity (BCVA) in the better eye was 0.5 ± 0.28 and in the worse eye was 1.0 ± 0.57. After the worse eye ONSF, at 1st week mean BCVA in better eyes was 0.27 ± 0.32 (p-value=0.001), while it was 0.43 ± 0.63 (p-value=0.006) in the worse eyes. At 2nd year follow-up after optic nerve sheath fenestration mean BCVA in better eyes was 0.30 ± 0.30 (p-value=0.002) and in worse eyes was 0.44 ± 0.63 (p-value=0.007). Four patients (44.4%) had a subconjunctival hemorrhage, two patients (22.2%) had binocular diplopia, one patient (11.1%) pre-septal cellulitis, and one patient (11.1%) had no improvement in vision because of pre-operative secondary optic atrophy. All patients had unilateral fenestration and bilateral improvement, six patients (66.67%) reported improvement in headache and successful tapering of medical therapy. Conclusion: Optic nerve sheath fenestration is effective as well as a safe surgical procedure to salvage acutely threatened vision in patients of Idiopathic Intracranial Hypertension on maximal medical treatment.
ABSTRACT
Objectives: To compare the effectiveness of fluid-air exchange with silicone oil-fluid exchange in reducing the residual silicone oil (SO) droplets after the removal of SO. Methods: This was a prospective, quasi-experimental study conducted from October 2021 to February 2022 at Eye Unit-III, COAVS, Mayo Hospital, Lahore. Sixty-one patients with siliconized eyes underwent removal of SO with two different techniques and were divided into fluid-air exchange and oil-fluid exchange groups. To quantify the residual silicone droplets objectively, B-scan echographic images were analyzed within seven days of surgery. Silicone oil index (SOI) which is the amount of residual SO droplets/vitreal area in the images was calculated with the help of imagej software. Results: The residual SOI of the fluid-air exchange group (0.99 ± 1.76%) was significantly lower than the oil-fluid exchange group (3.25 ± 3.85%). The SOI is positively correlated with the duration of tamponade, preoperative intraocular- pressure and axial length. Persistent IOP elevation post-operatively was seen in 16.67% individuals in the fluid-air exchange group and 54.8% individuals in the oil-fluid exchange group. Conclusion: Fluid-air exchange group was found to be superior in reducing residual SO droplets than the oil-fluid exchange group.