CASE 17587 Published on 17.01.2022

Dangerous black fungus intercavernous spread



Case Type

Clinical Cases


Dr. Divya Pabbisetti

Department of Radiology, Krishna institute of medical sciences, Secunderabad, Telangana, India


48 years, male

Area of Interest CNS ; Imaging Technique MR, MR-Angiography
Clinical History

A 48-year-old male presented with complaints of swelling of right eye with ptosis and restriction of eye movements. He had history of COVID 19 pneumonia one month before the present complaints and treated with steroids. He is a type II diabetic with uncontrolled sugars.

Imaging Findings

MRI of brain, orbits and PNS was done which showed right orbital cellulitis with cavernous sinus thrombosis, angioinvasion into right ICA causing its occlusion, resulting in anterior superficial watershed infarct. Right temporal cerebritis was also seen in the first scan. Left ICA was normal. When the scan was repeated the next day in view of clinical deterioration, we observed focal luminal narrowing in cavernous segment of left ICA. However there was no left sided orbital cellulitis. Left orbital apex and left cavernous sinus looked structurally normal. So we postulated that the reason for angioinvasion into left ICA was via the intercavernous sinuses.


Mucormycosis is a fulminant disease caused by fungi of Mucorales order ie mucor, absidia, Rhizopus. It is potentially lethal owing to its angioinvasive nature. Neuroimaging particularly MRI with gadolinium is the imaging modality of choice. [1] Early diagnosis, particularly of angioinvasion is essential as it has management implications.  

Cavernous sinus involvement is diagnosed by increase in size, loss of flow void, convex lateral margin and dilated superior ophthalmic vein. Absence of contrast enhancement is not a sensitive sign because an organizing thrombus can enhance [2].

In the context of invasive fungal sinusitis and orbital sinusitis cavernous sinus thrombosis can occur secondary to thrombosis of superior ophthalmic vein or direct extension of disease process from orbital apex. Angioinvasion of cavernous ICA occurs secondary to this [3].

Cavernous sinuses are connected by 4 venous sinuses namely anterior intercavernous sinus, posterior intercavernous sinus, inferior intercavernous sinus, dorsum sellae sinus and basilar sinus which can be variably identified on CEMRI [contrast enhanced MRI] [4].  These sinuses act as pathways of spread of infection and thrombosis from one cavernous sinus to another. In our case there was intercavernous spread of infection from right cavernous sinus causing angioinvasion of left ICA. However there was no thrombosis of left cavernous sinus

To our knowledge, this is the first reported case of ROCM with intercavernous spread.


Intercavernous sinuses act as pathways of spread of infection from one cavernous sinus to the other.  This is a rare case of intercavernous spread of angioinvasion in a patient with rhino-orbitocerebral mucormycosis

Final diagnosis – First MRI -Rhino-orbitocerebral mucormycosis with right orbital cellulitis, cavernous sinus thrombosis, angioinvasion into right ICA causing its occlusion.

Follow up MRI done on the next day- Intercavernous spread of infection causing angioinvasion manifesting as focal stenosis in cavernous segment of left ICA

Written informed consent was obtained from the patient's attender as the patients clinical status was not stable

Differential Diagnosis List
Intercavernous spread of angioinvasion to ICA by mucormycosis
Rhino-orbitocerebral mucormycosis
Orbital cellulitis with cavernous sinus thrombosis
Intercavernous spread
Final Diagnosis
Intercavernous spread of angioinvasion to ICA by mucormycosis
Case information
DOI: 10.35100/eurorad/case.17587
ISSN: 1563-4086