Vitreous membranes post parsplana vitrectomy

A 57-year-old male presented with bilateral unlasered proliferative diabetic retinopathy. The right eye had a mature senile cataract with tractional retinal detachment (TRD) on ultrasound and inaccurate projection of rays; the left eye showed non-resolving vitreous hemorrhage (NRVH) with hand motions close to the face. The left eye received pre-operative intravitreal anti-VEGF followed by 25-gauge pars plana vitrectomy (PPV) with endolaser photocoagulation, fluid-air exchange, and intravitreal triamcinolone acetonide. Post-operatively, the patient was prescribed topical moxifloxacin 0.5% 4 times a day, prednisolone acetate 1% 6 times a day, and homatropine 2% 4 times a day. On post-operative day 1, the left eye had visual acuity of hand motions close to face, with an Intraocular Pressure (IOP) of 32 mm Hg, 1+ cells in the anterior chamber, and well-lasered retina. Eyedrop timolol maleate 0.5% twice a day was added. By day 3, a dense fibrinous web was noted in the vitreous cavity with a 40% air fill. The patient had no pain or redness, no signs of lid edema, 0.5+ cells in AC, and no hypopyon. The underlying retina was visible despite the bands and showed no signs of retinitis or any choroiditis. The posterior segment was devoid of vitreous cells or haze, as seen in Fig. 1.Figure 1: Fibrinous bands with intervening retina visible showing fresh laser marks without any vitreous hazeWhat is the cause of the vitreous membranes in this patient? Inadequate clearing of the tractional membranes encountered during surgery. Post-operative endophthalmitis due to the higher risk of infection in diabetics. Sterile fibrinoid vitreous reaction because of pro-inflammatory vitreous milieu. Organized membranes of vitreous hemorrhage following surgical trauma. Findings As the patient had no pain or redness with minimal AC reaction (0.5+ cells) with a clearly visible retina through the fibrinous webs, topical predacetate 1% was intensified to 2-hourly administration; homatropine 2% 4 times a day was continued, and oral prednisolone 40 mg once daily was initiated for 10 days with blood sugar monitoring. Subsequently, all the membranes resolved completely, and visual acuity improved to 20/60 by day 15. Fig. 2 shows the fundus picture at 1 month.Figure 2: Fundus picture at 1 month showing resolution of vitreous membranes with an attached retinaDiagnosis LE Transvitreal fibrinoid syndrome Correct Answer c) Sterile fibrinoid vitreous reaction because of pro-inflammatory vitreous milieu. Discussion Transvitreal fibrinoid syndrome is a rare, sterile inflammatory reaction seen in diabetic patients after PPV for complications such as NRVH and TRD.[1,2] The exact pathophysiology is unclear. However, the prevailing theory suggests that the pro-inflammatory vitreous milieu seen in diabetic patients, heightened by surgical trauma and endolaser, triggers fibrin formation.[2] Additionally, the air–fluid meniscus may provide a surface for fibrin polymerization.[1] It may represent a form of toxic anterior segment syndrome (TASS) in the vitreous cavity.[1] Vitreous fibrin webs are seen in the early post-op period, as early as day 1. The patient typically has no pain or congestion. There is minimal anterior chamber reaction, and classically, the retina is clearly visible in between the fibrinous webs. Patients generally have favorable outcomes just with intensive topical corticosteroid therapy.[1] Intravitreal tPA may be used to hasten the fibrin dissolution.[3] Only rarely is re-surgery required.[4] Despite the benign and rare nature of this disease, it is important to recognize it early and to differentiate it from early post-operative endophthalmitis. 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. Financial support and sponsorship: Nil. Conflicts of interest: There are no conflicts of interest.