Answer for BIR CoW 20 Jun 2021
Rhino-orbito-cerebral mucormycosis
Findings
T2 Hypointense soft tissue thickening in right ethmoid air cells, T2 FLAIR Hyperintensity in right temporal lobe and middle cerebellar peduncle, Right Intraconal Fat stranding with Proptosis, Soft tissue thickening in the region of Right cavernous sinus and Right Meckels cave, Relatively thickened Right Trigeminal Nerve showing Diffusion Restriction.
Discussion
1.Rhino-orbito-cerebral mucormycosis (ROCM) is considered as a rare invasive infection caused by class phycomycetes fungi involving immunocompromised patients, arising from nasal and sinus mucosa, with rapid spread to orbit and brain. Often referred to as the so-called black fungus, the incidence of mucormycosis has risen more rapidly during the second wave of COVID. Extensive angioinvasion is considered as the main cause leading to vascular thrombosis and tissue necrosis. Vascular involvement is a common cause of high morbidity and mortality,infiltrating cavernous sinus and orbital apex leading to cellulitis of face, loss of vision.Intracranial involvement can cause narrowing of internal carotid artery leading to ischemic infarcts. Meningeal involvement can be seen.
2.Imaging helps in diagnosis of ROCM and in evaluation of the extent of disease which plays a crucial role in early diagnosis and timely intervention. CT scan demonstrates nodular mucosal thickening and hyperdense content leading to erosions of bony sinus walls.
3.MRI provides better evaluation of intracranial and soft tissue involvement, skull base invasion, perineural spread and vascular obstruction. MRI demonstrates variable signal intensity depending on the sinus contents, due to iron and manganese in the fungal elements.MRI also shows invasion of orbital soft tissues, skull base infiltration, perineural spread , intracranial complications and vascular obstruction involving internal carotid artery.T2 slow flow can suggest internal carotid artery invasion by the fungus.
4.Perineural spread is most commonly seen in head and neck malignancies more often seen in adenoid cystic carcinoma. Fungal hyphae tend to involve nerves and vessel wall leading to perineural spread and cavernous sinus invasion.
5.In our case,perineural spread is seen along trigeminal nerve extending from right cavernous sinus and Meckels cave.
6.ROCM is considered as an emerging rapidly disseminating fungal infection when associated with immunocompromised conditions and carry fatal prognosis with cavernous sinus involvement. Hence, radiologists should evaluate the extension and involvement of invasive fungal sinusitis which can lead to early diagnosis and timely management with antifungal agents and surgical debridement further helps to reduce morbidity and mortality.
Reference:
1.Kirti Parsi,Raghavendra K.Itgampalli,R Vittal and Anjani Kumar:Perineural spread of rhino-orbitocerebral mucormycosis caused by Apophysomyces elegans
2.Javier Molina-Gil,Lucia Gonzalez-Fernandez,Carmen Garcia-Cabo:Trigeminal neuralgia as the sole neurological manifestation of COVID-19: A case report
3.Dr. Bhavani P. N, Dr. Shivanand V. Patil, Dr. Satish D. Patil:Imaging f
Findings
T2 Hypointense soft tissue thickening in right ethmoid air cells, T2 FLAIR Hyperintensity in right temporal lobe and middle cerebellar peduncle, Right Intraconal Fat stranding with Proptosis, Soft tissue thickening in the region of Right cavernous sinus and Right Meckels cave, Relatively thickened Right Trigeminal Nerve showing Diffusion Restriction.
Discussion
1.Rhino-orbito-cerebral mucormycosis (ROCM) is considered as a rare invasive infection caused by class phycomycetes fungi involving immunocompromised patients, arising from nasal and sinus mucosa, with rapid spread to orbit and brain. Often referred to as the so-called black fungus, the incidence of mucormycosis has risen more rapidly during the second wave of COVID. Extensive angioinvasion is considered as the main cause leading to vascular thrombosis and tissue necrosis. Vascular involvement is a common cause of high morbidity and mortality,infiltrating cavernous sinus and orbital apex leading to cellulitis of face, loss of vision.Intracranial involvement can cause narrowing of internal carotid artery leading to ischemic infarcts. Meningeal involvement can be seen.
2.Imaging helps in diagnosis of ROCM and in evaluation of the extent of disease which plays a crucial role in early diagnosis and timely intervention. CT scan demonstrates nodular mucosal thickening and hyperdense content leading to erosions of bony sinus walls.
3.MRI provides better evaluation of intracranial and soft tissue involvement, skull base invasion, perineural spread and vascular obstruction. MRI demonstrates variable signal intensity depending on the sinus contents, due to iron and manganese in the fungal elements.MRI also shows invasion of orbital soft tissues, skull base infiltration, perineural spread , intracranial complications and vascular obstruction involving internal carotid artery.T2 slow flow can suggest internal carotid artery invasion by the fungus.
4.Perineural spread is most commonly seen in head and neck malignancies more often seen in adenoid cystic carcinoma. Fungal hyphae tend to involve nerves and vessel wall leading to perineural spread and cavernous sinus invasion.
5.In our case,perineural spread is seen along trigeminal nerve extending from right cavernous sinus and Meckels cave.
6.ROCM is considered as an emerging rapidly disseminating fungal infection when associated with immunocompromised conditions and carry fatal prognosis with cavernous sinus involvement. Hence, radiologists should evaluate the extension and involvement of invasive fungal sinusitis which can lead to early diagnosis and timely management with antifungal agents and surgical debridement further helps to reduce morbidity and mortality.
Reference:
1.Kirti Parsi,Raghavendra K.Itgampalli,R Vittal and Anjani Kumar:Perineural spread of rhino-orbitocerebral mucormycosis caused by Apophysomyces elegans
2.Javier Molina-Gil,Lucia Gonzalez-Fernandez,Carmen Garcia-Cabo:Trigeminal neuralgia as the sole neurological manifestation of COVID-19: A case report
3.Dr. Bhavani P. N, Dr. Shivanand V. Patil, Dr. Satish D. Patil:Imaging f
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!