Surgical Approach to Rhino-Orbital Mucormycosis using Contrast Enhanced MRI as Roadmap

Abstract

Introduction Increase in Mucormycosis cases following COVID-19 infection was major concern due to angio-invasive nature causing necrosis. Aggressive surgical resection is necessary to combat this infection. Identifying areas of involvement like orbit, infratemporal fossa and nature of involvement (enhancing or non-enhancing) is best assessed by MRI. Hence, we decided to use MRI as surgical roadmap for disease clearance. Materials and Methods All post-COVID suspected mucormycosis cases based on clinical suspicion underwent MRI and nasal endoscopic biopsy. In MRI we evaluated T1 with contrast and T2 with fat suppression. Once Mucormycosis was confirmed by biopsy, Amphotericin B was started with monitoring of biochemical parameters. Surgical resection till level of viable tissue was reached was done based on MRI findings. Post-operatively patients underwent nasal douching and endoscopic surveillance. Results Our surgical experience shows that maximum patients had to undergo unilateral FESS with modified endoscopic Denker’s approach and opening of pterygopalatine and infratemporal fossa. We conclude that all patients must minimally undergo the above surgery. Endoscopic Denker’s approach allows easy post-operative surveillance. The pterygopalatine and infratemporal fossa is anatomically hidden by posterior wall of maxilla. Since we found more than 50% involvement of these areas, the necessity to open and visualise the areas in our opinion is must in all cases of post-COVID rhino-orbital mucormycosis. Conclusion Post-COVID Rhino-Orbital Mucormycosis requires high index of suspicion. Underrated symptoms like headache, facial pain and facial swelling in post-COVID patients with associated immunocompromised state like diabetes mellitus must be thoroughly investigated by MRI nose, paranasal sinus and orbit. Surgical debridement as dictated by MRI and routine inspection of pterygopalatine and infratemporal fossa should be done.

Keywords

• Mucormycosis
• COVID-19
• Endoscopic Sinus Surgery
• Debridement
• Magnetic Resonance Imaging