A New Proposed Combined CT and MRI Staging System for Covid-19-Associated Rhino-Orbito-Cerebral Fungal Infection: A Multi-center Study with Pathological Correlation.

Rationale And Objectives: To propose a combined computed tomography (CT) and magnetic resonance imaging (MRI) based classification system in the management of COVID-19-associated rhino-orbito-cerebral (C-ROC) fungal infection and to assess the reliability of such proposed staging system.

Materials And Methods: This was a multi-center prospective study conducted on 122 adults with previously confirmed COVID-19 infection. CT and contrast-enhanced MRI (CE-MRI) were performed for all patients. Three radiologists (with experience of 8, 10, and 14 years) independently assessed all images. Then, each patient was assigned a radiological stage based on the five stages of the proposed system according to the radiological extent of the fungal infection. The intra-class correlation coefficient (ICC) test assessed the inter-rater agreement. Based on the pathological evaluation of post-operative specimens, a diagnosis of fungal infection was documented.

Results: The most prevalent severity stage among all raters was stage IV in 29.5-31.1% patients. The overall inter-rater agreement of the proposed staging system was excellent (ICC 0.971, 95% CI;0.960-0.979). Moreover, the most common detected pathogen was Mucormycosis (n = 87, 71.3%). Furthermore, there was a statistically significant association between the patients' outcome and the severity stage (P value 0.001) and there was no statistically significant association between ethmoid and sphenoid sinus affection and cranial extension (P value 0.081).

Conclusion: Our proposed combined CT and MRI severity staging system has a high inter-rater agreement. Moreover, it can aid in the early detection of the C-ROC fungal infection, improve preoperative planning, and subsequently improve the patient's outcome.