Efficacy of transcutaneous retrobulbar amphotericin B in post-COVID-19 rhino-orbito-cerebral mucormycosis: A single-center retrospective observational study.

Abstract

Background
Rhino-orbito-cerebral mucormycosis (ROCM) emerged as a severe opportunistic fungal infection during the post-COVID-19 period, particularly among patients with diabetes and those treated with corticosteroids. The angioinvasive nature of mucormycosis often limits the efficacy of systemic antifungal therapy due to poor tissue penetration. The present study aimed to evaluate the clinical outcome of transcutaneous retrobulbar amphotericin B (TRAMB) as an adjunctive, globe-sparing treatment in patients with post-COVID-19 ROCM.

Methods
A retrospective observational study was conducted on 40 biopsy-confirmed cases of post-COVID-19 ROCM admitted to the Government General Hospital, Nizamabad. Patients were categorized into four stages (3a–3d) according to the classification proposed by Honavar. All patients received retrobulbar injections of liposomal amphotericin B (3.5 mg/mL) in addition to systemic antifungal therapy and sinus debridement. Demographic characteristics, clinical features, and treatment responses were analyzed.

Results
The study population predominantly comprised males (82.5%) with a mean age of 54.6 years. The majority of patients were within the 40–60-year age group (55%) (Table 1, Table 2). Common presenting features included proptosis, extraocular muscle (EOM) restriction, and ptosis, which varied across disease stages (Table 3). Complete clinical recovery was achieved in all patients with early-stage disease (Stages 3a and 3b), whereas partial improvement was observed in Stage 3c, and minimal response in Stage 3d (Table 4). Two patients with advanced disease succumbed to cranial involvement.

Conclusion
TRAMB was found to be a safe, effective, and minimally invasive adjunct in managing mild-to-moderate orbital mucormycosis. Early administration improved ocular outcomes and prevented progression to irreversible orbital damage or exenteration.

Recommendations
Prompt diagnosis and early initiation of TRAMB therapy should be considered in patients with limited orbital involvement to maximize visual preservation. Incorporating TRAMB into multidisciplinary treatment protocols may enhance recovery and reduce morbidity in ROCM.