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Abstract Introduction The nasopharynx and oropharynx are the main colonization sites of coronavirus. Therefore, patients with paranasal sinuses and pharyngeal problems (ear, nose, and throat [ENT] patients) predispose coronavirus infection. Ear, nose, and throat patients with concomitant asymptomatic coronavirus infection may develop severe pneumonia following surgical procedures. As a result, presurgical screening for coronavirus infection is a substantial concern. Objective We evaluated the usefulness of a spiral chest computed tomography (CT) scan in the diagnosis of asymptomatic coronavirus infection in the presurgical assessment of ENT patients Methods In this study, candidates of paranasal sinus or pharyngeal surgery were evaluated for coronavirus infection. Patients with neither history of coronavirus disease 2019 (COVID-19) nor compatible symptoms and signs were screened for asymptomatic coronavirus infection. These patients composed two groups: the first group underwent a reverse transcription polymerase chain reaction (RT-PCR) test of nasopharyngeal sample and spiral chest CTscan, but for the second one, only the latter was performed. Results In the first group, which consisted of 106 patients, 11 (10.4%) cases had positive RT-PCR test results, and 17 (16%) patients showed positive findings in favor of coronavirus infection in the spiral chest CT scan. In the second group, which consisted of 173 patients, 34 (19.7%) cases had positive chest CT scan results. Conclusion The chest CT scan has a valuable role in the early diagnosis of asymptomatic coronavirus carriers in patients highly predisposed to infection, especially in low resource areas, where the RT-PCR test is unavailable.
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Abstract Introduction The most common site of salivary gland tumors is the parotid gland. Computed tomography (CT), magnetic resonance imaging (MRI), and sonography are imaging modalities to differentiate benign from malignant parotid tumors. Objective The aim of this study is the evaluation of the diagnostic value of perfusion CT for differentiating histological categorization of benign and malignant parotid tumors. Methods A total of 29 patients with parotid neoplasms were enrolled in this study. Mean age and all CT perfusion variables (gradient and permeability, blood flow[BF], blood volume [BV], mean transit time [MTT], permeability surface [PS], maximum intensity projection [MIP], time-density curve [TDC], and time to peak [TTP]) were compared among three groups (malignant tumors [MTs],Warthin's tumor [WT] and pleomorphic adenomas [PA]). Results The mean age of the patients was 55.9±14.1 (26-77), and 15 of them were male (51.7%). Eleven lesions were PAs [37.9%], 8 lesions were WTs (27.6%0 and 10 lesions (34.5%) were MTs (6 acinic cell carcinomas [ACCs], 3 adenocystic carcinomas [AdCCs], and 1 mucoepidermoid carcinoma [MEC]). The mean age of the patients with WTs was 62±7.5 years; 52±14.2 for patients with Pas, and 55.2±17.2 for those with MTs (p=0.32). The mean MIP was 122.7±12.2 in WT, while it was 80.5±19.5 in PA, and 76.2±27.1 in MTs (p<0.001); The mean MIP for WT was higher than for PAs and MTs; the values of MTs and PAs were not statistically different. The average of BF, BV, and curve peak were higher inWTs in comparison with the other two groups, and curve time 2 and TTP were higher in PAs in comparison with MTs. Conclusion Based on this study, perfusion CT of the parotid gland and its parameters can distinguish between benign and malignant parotid masses.
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ABSTRACT Objective: Magnetic resonance spectroscopy (MRS) is a powerful tool for structural studies of chemical compounds and biomolecules and also documented promising findings as a potential imaging technology in thyroid oncology. This prospective study was to ascertain the clinical significance of 3 Tesla MRS in the evaluation of patients with thyroid nodules (TNs) as an ancillary diagnostic technique for thyroid carcinoma. Materials and methods: Magnetic resonance spectroscopy at 3T at echo- times (TEs) 136 and 270 ms was carried out on 15 patients with total number of 32 TNs larger than 1 cm3, which all were surgically resected. Choline (Chol) to creatine (Cr) ratio was assessed at 136 and 270 TEs on each nodule and a receiver operating characteristic (ROC) curve was used to determine optimal cut-off point. The findings were compared with histopathology of thyroid specimens. Results: There were 23 benign and 9 malignant lesions (7 papillary and 2 follicular thyroid carcinomas). The mean values of Chol/Cr at 136 and 270 TEs was 2.28 ± 3.65 and 1.52 ± 1.67 respectively and the difference between benign and malignant nodules was only significant at 136 TEs. The study revealed that Chol/ Cr ratio cut-off point of 2.5 best correlates with histopathology results (sensitivity = 75%; specificity = 100%; PPV = 100%; NPV= 92%). Conclusion: This preliminary study showed that 3T magnetic resonance spectroscopy might be a specific modality for the evaluation of thyroid nodules in differentiation of benign from malignant thyroid tissue. However, a larger series would give much greater confidence that this state-of-the-art technology will worth pursuing in clinical practice.