Unilateral retinopathy post perilesional interferon α2b injections for ocular surface squamous cell carcinoma

Topical interferon therapy in uveitic macular edema

Purpose

To evaluate efficacy of topical interferon alfa-2b (IFN) in the treatment of uveitic macular edema (UME).

Methods

This is a prospective, interventional case study of patients with UME. Injection IFN was reconstituted into eye drops and a four times/day (QID) application was prescribed. Central macular thickness (CMT) on optical coherence tomography (OCT) scan was evaluated. Improvement in CMT by ≥50 μm from the baseline was studied in eyes with presenting CMT ≥400 μm.

Results

Twenty eyes of 20 patients with UME were studied: anterior uveitis (n = 3), anterior + intermediate uveitis (n = 5), posterior uveitis (n = 3), retinal vasculitis (n = 3), and panuveitis (n = 6). Mean CMT at the presentation was 423.3 μm (range: 270-604 μm), which improved at 1 month (n = 16), 2 months (n = 10), and ≥3 months (n = 11) follow-up, to 415.3 μm (range: 247-579 μm) (P = 0.411), 364.4 μm (range: 258-566 μm) (P = 0.099), 344 μm (range: 258-484 μm) (P = 0.001), respectively. Twelve eyes of 12 patients had presenting CMT ≥400 μm. In these cases, decrease in CMT by ≥50 μm was seen in 4/10, 4/5, and 5/6 eyes at 1 and 2 months and ≥3 months follow-up. Mean follow-up was 4 months (range: 1-17 months). Complete resolution of UME was seen only in three eyes. No ocular or systemic side effects were observed.

Conclusion

Topical IFN therapy in QID doses is safe but may have limited role in UME. Long-term therapy may improve its efficacy. Larger studies with dose modification, combination with other drugs, and with homogeneous uveitis population are recommended.

Intensive topical interferon therapy in uveitic macular edema

Purpose

To evaluate the efficacy of intensive topical interferon alfa-2b (IFN) therapy in uveitic macular edema (UME).

Methods

This is a prospective, interventional case study of eyes with UME. Commercially available injection IFN for subcutaneous use was reconstituted to form eye drops and a dose of 6 times/day for 2 weeks, 5 times/day for next 2 weeks, followed by 4, 3, 2, 1 taper per month was prescribed. Optical coherence tomography (OCT) and clinical examination was done at 0, 2, 4, 8 weeks, and further as required.

Results

Nine eyes of 9 patients with UME were studied. Mean central macular thickness (CMT) at presentation was 522.2 μm (range: 408-803 μm). At 2-week, 1-month, and 2-month follow-up, mean CMT decreased to 451.6 μm (range: 322-524 μm), 375.8 μm (range: 287-480 μm), and 360.3 μm (range: 260-485 μm), respectively. Four eyes which showed inadequate response to previous topical IFN therapy (4 times/day) showed significant improvement with intensive therapy at 1 month follow-up. In 4 eyes, UME resolved completely with mean CMT 285.5 μm (range: 260-312 μm) at 7.5 weeks (range: 4-12 weeks). Study exit was seen in 2 cases due to inadequate response and relapse of uveitis. Mean follow up was 3.38 months (range: 1-5 months).

Conclusion

Intensive topical IFN therapy can be an alternative therapeutic option in the treatment of UME. Study of intraocular penetration, combination with other drugs, and the efficacy of IFN separately for different uveitic entities may explore new avenues in treatment of UME.