Eyes wide open: Detecting neovascularization to prevent acts of omission

Neovascular glaucoma (NVG) is a form of secondary glaucoma characterized by new vessels on the iris and the angle of the anterior chamber.[1] NVG is a sight-threatening condition which usually runs an aggressive course and is important to prevent the neovascularization from occurring in the first place. About one-third cases of neovascularization of the iris (NVI) progress to neovascularization of angle (NVA) leading to NVG and in 22% cases is associated with (central retinal vein occlusion [CRVO]).[2] We present to you this case to emphasize on the importance of thorough clinical examination of a patient with high risk of developing NVG. Case Report A 60 years old Female presented to the OPD with a complaint of gradual, painless, and progressive diminution of vision of left eye for 2 months. She was a known case of Diabetes Mellitus since several years and blood sugar level had not been under control, proven by her HbA1C of 12.5. She had already consulted two Ophthalmologists a week prior and was diagnosed with Left Eye Central Retinal Venous Occlusion (CRVO). She had no history of ocular trauma or ocular surgery and was not on any topical medications. Her best corrected vision of right eye was 6/6 however, of the left eye was only Hand movements close to face with accurate projection of rays in all four quadrants. Her best-corrected vision of the right eye (RE) was 6/6, however, the LE only Hand movements close to the face with accurate projection of rays in all four quadrants. While the Slit Lamp examination of right eye was unremarkable, her left eye revealed a presence of 360 degrees neovascularization of iris (NVI) [Figure 1a and b] along with grade 2 relative afferent pupillary defect and Immature cataract. Intraocular pressure with applanation tonometry of right eye (RE) was 14 mmHg and of left eye (LE) was 48 mmHg. Gonioscopy also showed Neovascularization of angle (NVA) in all four quadrants. Dilated Fundus examination of left eye revealed Neovascularisation of disc (NVD) with dot blot haemorrhages in all four quadrants [Figure 1c and d] involving the macula and paramacular region with tortuous vessels.Figure 1: (a and b) Neovascularization of Iris of left eye in all 12 clock hours; (c and d) Dot blot haemorrhages in all four quadrants and Neovascularization of disc noted on fundus examination of left eyeIn the consultations that the patient had had previously, the presence of neovascularisation of iris and angle was missed, due to which she was not given any treatment for it. Her condition had progressed to cause Neovascular Glaucoma (NVG). Missing this disease entity is an act of Omission as NVG typically results in severe vision loss along with a possible blind painful eye and carries a poor prognosis. Once properly diagnosed, patient underwent a total of 5 sessions of Pan retinal photocoagulation (PRP) in a span of 2 weeks along with commencement of anti-glaucoma medications and one intravitreal Anti-VEGF injection (Ranibizumab). She also has consultation done with a physician in view of raised blood sugar level and uncontrolled diabetes after which the dosage of her Oral Hypoglycaemic drugs was revised. After the rigorous treatment her NVI and NVA resolved completely [Figure 2], IOP came down to 20 mmHg and vision improved to 6/24.Figure 2: (a and b) Fundus photo of Left eye after 3 sessions of Pan-retinal photocoagulation (PRP) laser; (c and d) Anterior segment photo of Left eye after 3 sessions of PRP laser showing resolved NVIAfter the rigorous treatment, her NVI and NVA resolved completely, her IOP came down to 20 mmHg, and her vision improved to 6/24. The patient then underwent cataract surgery along with a second dose of intravitreal anti-VEGF injection. Postoperatively, she continued her antiglaucoma medication for optimal control of her IOP and is currently on regular follow-up. Discussion CRVO is one of the main causes of sudden painless vision loss in adults and prevalence is about 0.8 per 1000.[3] Approximately 60 % cases of Ischaemic CRVO develop NVI. Every CRVO patient requires regular IOP monitoring and regular slit lamp examination. Early detection and prompt treatment of NVI is essential to prevent progression to NVG and consequent loss of vision. Missing critical findings is considered an act of omission underscoring the importance of timely management. In such cases it is imperative to emphasise on the urgent need to lower the intraocular pressure while reducing the progression of neovascularisation through pan retinal photocoagulation (PRP). In such cases, it is imperative to emphasize the urgent need to lower the IOP while reducing the progression of neovascularization through PRP. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Data availability statement The data supporting the findings of this study will be made available upon reasonable request. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.