RPS 1608 - Orbital and paranasal sinus imaging

Author Block: O. Pavlova, N. S. Serova, D. Davydov, S. K. Ternovoy; Moscow/RU
Purpose or Learning Objective: To investigate the influence of orbital volume and globe position on the outcome in patients with orbital trauma using СT data postprocessing.
Methods or Background: A total of 107 patients with orbital trauma (100%) were admitted to the Sechenov University hospital. The patients were divided into 3 groups: 50 patients (47%) in the acute period (up to 2 weeks after the trauma), period of developing of posttraumatic deformities (n=30; 28%) (up to 3 months), period of posttraumatic deformities (n=27; 25%) (after 3 months). MSCT was performed using Canon Aquilion One 640, CT data processing was performed using workstation Vitrea Core. Along with the classical bone and soft tissue trauma evaluation on CT, the examined parameters of CT analysis included orbital volume measurement and evaluation of globe position.
Results or Findings: CT revealed the bone and soft tissue structures trauma in 100% of patients, however, the parameters of CT data analysis allowed to additionally reveal increased traumatic orbital volume in 21 patients (19%) and additional enophthalmos in 9 patients (8%), which helped to change the treatment tactic in 12 patients (11%).
Conclusion: The postprocessing of CT data allowed developing new specific criteria such as orbital volume measurement and globe position analysis which increase the efficiency of preoperative planning and help to reduce the possibility of postoperative complications in patients with orbital trauma.
Limitations: No limitations were identified.
Ethics committee approval: Approved by Sechenov University ethics committee.
Funding for this study: No funding was provided for this study.

"Author Block: C. Shen; Beijing/CN
Purpose or Learning Objective: Accurate staging of thyroid-associated ophthalmology (TAO) is crucial for the choice of treatment. Conventional MRI has only limited utility on this purpose. We proposed that quantitative imaging methods are superior in proper staging of TAO.
Methods or Background: Twenty patients with TAO were retrospectively enrolled, and clinical activity score (CAS) was used to determine the disease activity and severity. Conventional MRI, fat fraction, T1ρ imaging and T2 mapping were acquired. Volumes of intra-orbital fat were measured in T1FLAIR sequences. Fat fraction, T1ρ and T2 relaxation time in each extraocular muscle were measured. Independent sample t-test, and Spearman correlation analysis were used for statistical analysis.
Results or Findings: No significant difference was found in intra-orbital fat volumes between active (CAS ≥ 3) and inactive (CAS < 3) TAO patients (p=0.816), the fat volumes showed no correlation with CAS scores (p=0.2). T2 relaxation time of inferior rectus (IR) was higher in the active group (p=0.03). Fat fraction of medial rectus (MR) decreased with CAS, T1ρ of IR, MR and lateral rectus (LR) increased with CAS, and T2 relaxation time of MR and LR increased with CAS (all p<0.05).
Conclusion: Intra-orbital fat volumes might not help to differentiate the activity and severity of TAO. Quantitative magnetic resonance imaging (MRI) might provide accurate parameters delineating the activity and severity of TAO, thus aiding the appropriate choice of treatment.
Limitations: More cases would be involved into the analysis, as well as long-term follow-up in order to assess the role of quantitative MRI in predicting the progression and prognosis of TAO.
Ethics committee approval: This research had been approved by our institutional review board.
Funding for this study: No funding was provided for this study.

Author Block: K. A. Bhagwat¹, K. peethambaram¹, v. k. hancginal²; ¹Davangere/IN, ²Gadag/IN
Purpose or Learning Objective: Unilateral proptosis in post-COVID is one of the clinical signs which needs imaging. The purpose of this study was (1) the early identification of mucormycosis on imaging - that is essential, (2) assessment of the spectrum of ocular involvement of mucormycosis in post-COVID status causing proptosis, and (3) to identify cavernous sinus involvement/thrombosis leading to dilatation of superior ophthalmic vein.
Methods or Background: Retrospective data analysis has been done from three district teaching hospitals, where CT/MRI have been performed for post-COVID patients presenting with unilateral proptosis to evaluate for the rhinoocculocerebral mucormycosis. 1.5 T MRI / 16 Slice MDCT scanner have been used for orbital imaging. We have considered all post-COVID patients who underwent imaging for unilateral proptosis for evaluation. Two radiologists, with 16 and 8 years of experience, have read PACS images.
Results or Findings: A total of 119 patients have undergone imaging for mucormycosis among whom 65 patients had presented with unilateral proptosis. Involvement of mucormycosis soft tissue with erosive changes in the medial wall (from ethmoid sinus), floor (maxillary sinus), orbital apex (sphenoid sinus) leading to proptosis was found in 61 patients. Dilated superior ophthalmic vein due to cavernous sinus thrombosis was identified in four patients as the cause of proptosis with coexisting sinus involvement. Preseptal oedema, premaxillary oedema, oedema of soft tissue around the orbit and sinuses were found in 30 patients.
Conclusion: Imaging early in unilateral proptosis helps identify mucormycosis. Assessment of involvement of orbital wall and erosive changes helps as a surgical road map.
Limitations: Since only unilateral proptosis is considered as a criterion. Other early symptoms/signs of facial swelling, preseptal oedema leading to imaging would identify mucor much earlier.
Ethics committee approval: Retrospective study of images on PACS, approval taken.
Funding for this study: No funding was received for this study.

Author Block: L. Yunusova, S. Valiyev; Tashkent/UZ
Purpose or Learning Objective: Report CT manifestations and outcomes of rhino-orbital cerebral mucormycosis (ROCM) in patients with COVID-19.
Methods or Background: We investigated 110 patients of invasive ROCM between July 2020 -September 2021, who were treated for the Maxillofacial Surgery of the TMA. The examined patients were from 46 to 52 years old and were men - 59.5%, women - 40.5%.
Results or Findings: Clinical features of these patients presents: sixty-eight (61,8%) patients had onset of their disease with toothache with one developing submandibular abscess later, one with otitis externa and perichondritis followed by ophthalmoplegia, and one with catarrh. Twenty-eight (25,4%) patients had altered sensorium at presentation, while two others developed it during their hospital stay, one due to internal carotid artery occlusion, and the other due to hydrocephalus. Ophthalmoplegia (89%) was the most frequent presentation followed by proptosis (83%). Visual loss (80%) was observed in 26 (23,6%) patients at presentation and two patients developed it during their hospital stay. One patient had bilateral proptosis, ophthalmoplegia, and visual loss. On CT imaging, all patients had evidence of paranasal sinuses involvement. The ethmoid (86%) and maxillary sinuses (80%) were most commonly involved, followed by sphenoid and frontal sinus in fifty-six (50,9%) each and pansinusitis in seventy-five (68,1%). Forty-eight (43,6%) patients had a gas shadow over the maxilla suggestive of secondary bacterial infection. Intracranial extension with cerebral lobe involvement presenting as a hypodense area with or without rim enhancement was observed in seven (40%) patients. One of these patients had a massive cerebral infarct with marked perilesional oedema resulting in hydrocephalus, which required ventriculoperitoneal shunt placement, and the other had internal carotid artery occlusion.
Conclusion: Computed tomography imaging is a useful modality to assess the extent of the ROCM.
Limitations: No limitations were identified.
Ethics committee approval: This study was approved by the ethics committee.
Funding for this study: No funding was provided for this study.