 Hello everybody, I'm Dr. Bohini Preeti. I'm doing my radiology residency from Babbar Mahavi Jane Hospital. My topic for presentation is Chromatic Spectrum of MRA CT imaging findings in Rhino-Arbiter Cerebral Mucor Microsis and post-COVID-19 patients. Co-authors are Dr. Praveen Kumar and Dr. Gnana Prakash. Mucor Microsis is a severe opportunistic fungal infection that results from a fungus of order mucarils. During second wave of COVID-19, significantly increased number of Rhino-Arbiter Cerebral Mucor Microsis were encountered. Because of its rapid spread and angiotinvasion, it has varied presentation among patients. Cross-sectional imaging has an important role in diagnosing cases of ROCM and also helps in assessing the spread of infection, staging of disease, prognostication and follow-up. With different clinical presentation, we reported various imaging findings from 37 patients with COVID-19 infection and invasive ROCM from our hospital. Risk factors, immunosuppression, corticosteroid administration and uncontrolled diabetes, pathogenesis, COVID-19 is a pro-coarchable state and there is incidence of thrombotic events. This pro-coarchable state forms ground for angiotinvasion leading to vessel thrombosis and dissemination of infection. Pathway of spread of ROCM can be direct spread or through pteripopalatin, FOSA, or through sphenoid sinus from mycelary sinus into the adjacent soft tissue or from the ithomoid sinus into the orbital apex and into the cavernous sinus. We have categorized our patients based on the following classification. On average, SG proposed four state system to determine the anatomical extent and severity of ROCM. Stage one, disease was limited to nasal mucosa, stage two, extended into para nasal sinuses, stage three, involving the orbit and stage four, involvement of the central nervous system. We have retrospectively reviewed the cases of ROCM with the history of COVID-19 infection in the recent past. Most of the patients presented with facial pain and facial numbness, orbital pain and periorbital swelling, conjunctival suffusion, diminution of vision to complete of Thalmuclecia blindness, headache and stroke like features. Patients in our study had undergone MRA scanning of para nasal sinuses, orbit, brain and brain with contrast in 1.5 Tesla GE Optima 360 MR machine. CT imaging were performed using 16 slice GE Optima 540 CT scanner. MRA protocol followed at our hospital was coronal T1 weighted and stir sequences, axial stir sequence, axial diffusion, flare and gradient sequences of brain, post contrast axial, sagittal and coronal T1 fat set sequences. Coming to imaging interpretation in our patients, coronal and axial stir sequences showed polyporeal mucosal thickening of the right maxillary sinus and there was involvement of the right terbynate. Post contrast showed peripheral enhancement with the central non-enhancing area with the peri sinus fat strand. Another patient showed polyporeal mucosal thickening involving the right maxillary sinus and there was involvement of the right cheek showing edematous changes. And on post contrast there was non enhancement of the mucosal of the right maxillary sinus with the peri sinus fat strand. This patient showed the imaging findings of polyporeal mucosal thickening involving the bilateral maxillary sinus and on post drop there was peripheral enhancement with the central non-enhancing area. And on corresponding CT image showed bony erosions of the maxillary sinus, walls of the maxillary sinus involving the posterior wall, medial wall and edges in nasal veins. This was a post drop patient on the left side with a recurrence of infection on the right side showing polyporeal mucosal thickening in the right maxillary sinus and the disease was seen extending into the bilateral etymol sinus. On post contrast there was peripheral enhancement with the central non-enhancing area. This was also a post drop patient came with recurrence of infection on the right side. On imaging there was polyporeal mucosal thickening of the right maxillary sinus. On post contrast there was evidence of involvement of the extracellular compartment of the inferior wall of the orbit and inferior rectus muscle. A corresponding section of the CT image showed the areas of bony erosion involving the walls of the maxillary sinus. This patient showed involvement of all the sinuses and there was a fat stranding noted in the retro orbital region of the left, retro orbital region of left orbit. On post contrast there was heterogeneous enhancement seen on the left orbit. This was also a stage 3 where orbital involvement was seen. This patient showed involvement of all the sinuses and left maxillary sinus showed areas of necrosis and areas of non enhancement seen in the mucosal of the left maxillary sinus. And there was area of necrosis noted in the medial wall of the orbit. Areas of bony erosion noted involving the orbital walls and facial bones involving the frontal psychomatic rib reform. Coming to stage 4 intrapranial extension. This was a post-op patient presented with the post-op patient now presented with recurrence of symptoms involving the involvement of residual sinuses. And now the disease was seen extending into the basic frontal region bilaterally. On post contrast there was peripheral enhancement of the lesion and similar lesion was also seen in the right ganglia capsular region. This patient had undergone stereotactic brain biopsy and abscess drainage was done which showed the fungal elements and following the procedure there was resolution of the lesion. And this was the first patient encountered at a hospital with the muper microsus now presented with left sided symptoms. Now on imaging there was extensive debulking done on the left side and DWI showed peripheral diffusion restriction and on post contrast there was peripheral enhancement indicating left temporal lobe abscess. This patient was also a post-op case came with recurrence of infection involving the spinoid sinus and the disease was seen extending into the cavernous sinus. There was a non-visualization of cavernous segment of the right internal carotid artery indicating internal carotid artery thrombosis. The same patient had also involvement of the skull base showing areas of bony erosions involving the clivus part foramen of skull base and most like mostly involving the right midiscranial fossa. This was also a post-op case came with recurrence of recurrence in the spinoid sinus and disease was also seen extending involving the roof of the right orbit and adjacent temporal and infertile temporal fossa. And disease was also seen involving the meninges there was meninges thickening and there was an axis in the right temporal lobe. On CT there was involvement of the frontal bone and spinoid sinus. This was also showing intracranial extension. This patient presented with stroke-like symptoms. She presented with a weakness on the right side. On T2 image there was hyperintensilation seen in the left thalamid area which showed blooming on GRE and peripheral diffusion restriction on DWI. Mild peripheral enhancement was noted in the post-contrast images. She had undergone stereotactic brain biopsy which turned out to be an abscess and that abscess was drained and specimens showed the elements of fungal hyphae. Following a post-procedure showed the resolution of the lesion. And another patient showed involvement of the skull base where the glibus was involved and most of the skull base including the middle cranial fossa was involved. In post-contrast there was heterogeneous enhancement of the glibus region. This patient showed evidence of an sinus involvement and there was involvement of the right orbit with the mild proctorosis and right cheek was also involved. And there was an area of infarct noted in the right middle cerebral artery territory with a mild mid-lineship noted. On microscopy, KOH Mountain HNA staining showed broad aseptic fungal hyphae that is a muper microsus. Now, Sino-Nezer involvement, maxillary sinus was involved in 32 patients, etymor sinus 19, frontal sinus 13, sphenoid sinus 8 patients showed the involvement of sphenoid sinus. Orbital involvement, orbital wall involvement was seen in 13 patients, extraconal intraconal compartment was seen in 8 patients, proctosis was seen in 9 patients. Roof and floor of the maxilla was seen in 8 patients, alveolar process of the maxilla was seen in 8 patients, ibomactic bone involved in 5 patients, clivus was involved in 3 patients. Meningial thickening, bilateral frontotemporal area was involved in 4 patients, bilateral frontotemporal, sylvian fissure was involved in 2 patients, thalamic lesion was involved in 2 patients and frontal lobesion was seen in 3 patients, cavernous sinus involvement was seen in 4 patients. I would like to conclude by saying that most of our patients presented with involvement of the paramesal sinuses extending to orbits and cranial cavity in few cases. While evaluating post-COVID-19 patients, high index of suspicion must be made for muper microsus and relevant MRD protocol should be followed. Therefore, it plays a major role in the earlier diagnosis of infection and extent of involvement. These are my references. Thank you.