Table 2.

Clinico-radiological classification system of post-covid mid-face mucormycosis

Class	Clinical features	Radiologic features (NCCT & MRI)
Stage-0 Unilateral or bilateral	A] Extra oral i) Pain over the midface, maxillary sinus and para nasal region B] Intra oral ii)Pain over the dentoalveolar and palatal region	A] Bony changes i)Change in the bony trabecular pattern of the hard palate and alveolar bone of the maxilla B] Soft tissue i) Polypoidal mucosal thickening confined to the floor and medial wall of the maxillary sinus
Stage-1a (oro sino nasal) unilateral involvement	A] Extra oral i) Swelling & pain over the cheeks & nasal region (Nasal & Para nasal region) ii) Nasal discharge iii) Paresthesia over cheek and infra orbital region B] Intra oral i) Draining sinuses with suppurative discharge over palate & buccal vestibule ii) Boggy, oedematous appearance of palatal & vestibular mucosa iii) Bluish/greyish black discoloration of mucosa iv) Frank ulceration of mucosa ± denudation of underlying bone v) Mobility of teeth vi) Dentoalveolar mobility	A] Bony changes i)Destruction of the hard palate ii) Destruction of alveolar bone of the maxilla iii) Destruction of inferior turbinate ± walls of maxillary sinus B] Soft tissue i)Involvement/Polypoidal mucosal thickening of maxillary sinus and/or ethmoid sinus
Stage-1b (oro sino nasal) bilateral involvement	A] Extra oral i) Swelling & pain over the cheeks & nasal region (Nasal & Para nasal region) ii) Nasal discharge iii) Paresthesia over cheek and infra orbital region B] Intra oral i) Draining sinuses with suppurative discharge over palate & buccal vestibule ii) Boggy, oedematous appearance of palatal & vestibular mucosa iii) Bluish/greyish black discoloration of mucosa iv) Frank ulceration of mucosa ± denudation of underlying bone v) Mobility of teeth vi) Dentoalveolar mobility	A] Bony changes i)Destruction of the hard palate ii) Destruction of alveolar bone of the maxilla iii) Destruction of inferior turbinate ± walls of maxillary sinus B] Soft tissue i)Involvement/Polypoidal mucosal thickening of maxillary sinus and/or ethmoid sinus
Stage-2a (oro sino naso orbital) unilateral involvement	3 or more Clinical Features of Type-1, with:- i)Watering of eye ii) Chemosis of bulbar conjunctiva of eye iii) Proptosis iv) Restricted ocular movements v) Diminished/sluggish pupillary reflex (Direct & Concensual) vi) Pain/tenderness over frontonasal and /or frontal bone region vii) Discoloration/Eschar over skin of mid face region	Radiographic Features of Stage -1, with:- A] Bony changes i)Destruction of lamina papyracea of ethmoid bone ii) Destruction of other bones of medial wall of orbit ± floor of orbit B] Soft tissue i)Invasion of extra conal fat of orbit ii) Involvement of extra ocular muscles of orbit (inferior oblique,inferior rectus,medial rectus) iii) Involvement of frontal sinus and/or sphenoid sinus
Stage-2b (oro sino naso orbital) bilateral Involvement	3 or more Clinical Features of Type-1, with:- i)Watering of eye ii) Chemosis of bulbar conjunctiva of eye iii) Proptosis iv) Restricted ocular movements v) Diminished/sluggish pupillary reflex (Direct & Concensual) vi) Pain/tenderness over frontonasal and /or frontal bone region vii) Discoloration/Eschar over skin of mid face region	Radiographic Features of Stage -1, with:- A] Bony Changes i)Destruction of lamina papyracea of ethmoid bone ii) Destruction of other bones of medial wall of orbit ± floor of orbit B] Soft tissue i)Invasion of extra conal fat of orbit ii) Involvement of extra ocular muscles of orbit (inferior oblique,inferior rectus,medial rectus) iii) Involvement of frontal sinus and/or sphenoid sinus
Stage-3 (Rhino orbito cerebral) [Intra-cranial/Cerebral involvement]	Features of Type-2,with:- i)Ptosis ii) Complete loss of ocular movements iii) Loss of visual acuity (Pupil fixed & unresponsive) iv) Hard, proptosed eyeball v) Pain over parietal and/or frontal region [Features suggestive of cranial nerves 3,4,6; intra cranial involvement]	Radiographic Features of Stage -2, with:- A] Bony changes i)Destruction of frontal bone cortex B] Soft tissue i)Involvement of orbital apex ii) Involvement of Cavernous Sinus iii) Enhancement of dura of brain or underlying neuroparenchyma

Significance of bold in Table 2 is to highlight relevant headings