Olfactory Neuroblastoma Is Not Always Located at the Roof of the Nasal Cavity.

Objectives: To evaluate the imaging characteristics of the tumor, emphasizing its location, and to determine the frequency of typical and atypical locations of olfactory neuroblastoma (ONB). Materials and Methods: We retrospectively reviewed the computed tomography and magnetic resonance imaging findings of patients with pathologically proven ONB between April 2000 and April 2023. Demographic information, chief complaints, tumor location, and tumor extension were extracted. Results: Of the 58 patients, 50 (86.2%) had the epicenter of the mass at the superior part of the nasal cavity, while eight patients (13.8%) had the epicenter at other atypical locations: seven patients (12.1%) at the middle part of the nasal cavity and one patient (1.7%) within both sphenoid sinuses. Conclusion: ONB is not always present in the upper part or the roof of the nasal cavity, and a significant number of ONBs are occasionally found in the rest of the nasal cavity and other atypical locations.

Correlation Between Coronavirus Disease 2019 Severity and Noninvasive Assessment of Liver Fibrosis in Patients with Metabolic Dysfunction-Associated Fatty Liver Disease.

BACKGROUND/AIMS: Metabolic dysfunction-associated fatty liver disease is a crucial global health concern. Studies have shown that metabolic dysfunction-associated fatty liver disease patients are at higher risk of severe coronavirus disease 2019. However, there are no precise measures of the correlation between the degree of metabolic dysfunction-associated fatty liver disease fibrosis and coronavirus disease 2019 severity. This study evaluated the association between metabolic dysfunction-associated fatty liver disease with varying degrees of fibrosis and coronavirus disease 2019 prognosis. MATERIALS AND METHODS: All hospitalized coronavirus disease 2019 patients who had liver steatosis as determined by computed tomography scan were included. Metabolic dysfunction-associated fatty liver disease was diagnosed in accordance with international consensus criteria. Liver fibrosis was assessed using the nonalcoholic fatty liver disease fibrosis score, FIB-4 and FIB-8 indexes. Coronavirus disease 2019 severity was defined using World Health Organization criteria. Logistic regression was used to determine the associations between varying degrees of fibrosis and the severity of coronavirus disease 2019. RESULTS: A total of 996 confirmed hospitalized coronavirus disease 2019 cases with complete data were reviewed; of these, 296 (29.7%) cases of metabolic dysfunction-associated fatty liver disease were diagnosed. Metabolic dysfunction-associated fatty liver disease patients with any fibrotic state had more severe coronavirus disease 2019 than nonmetabolic dysfunction-associated fatty liver disease patients (adjusted odds ratio 1.912, 95% CI 1.363-2.684; P < .05). Multiple logistic regression analysis showed that metabolic dysfunction-associated fatty liver disease patients with significant fibrosis according to the FIB-8 score were more likely to have severe coronavirus disease 2019 (adjusted odds ratio 5.458, 95% CI 1.481-20.110; P < .05). CONCLUSION: The presence of metabolic dysfunction-associated fatty liver disease in hospitalized coronavirus disease 2019 patients strongly correlated with the severity of coronavirus disease 2019. The hepatic FIB-8 index appears to provide the best prognostic value among the fibrosis scores in metabolic dysfunction-associated fatty liver disease patients with coronavirus disease 2019.

Lemmel syndrome, a rare cause of obstructive jaundice by periampullary duodenal diverticulum: Case report and review of the literature.

Lemmel syndrome is a pancreaticoduodenal disease caused by compression of the mid or distal common bile duct by a periampullary diverticulum. This condition should be considered a rare complication of a duodenal diverticulum and an unusual cause of obstructive jaundice. Because of its infrequent occurrence and non-specific clinical presentation, Lemmel syndrome can mimic other conditions. We herein report the clinical and imaging findings (computed tomography, magnetic resonance imaging) of a patient who presented with intermittent abdominal pain and jaundice. Large air-filled outpouching lesions of the duodenum compressed the biliary duct, resulting in upstream biliary ductal dilatation that led to the diagnosis of Lemmel syndrome.

Thyroid Incidentalomas in Hospitalized Patients With COVID-19: A Single-Center Retrospective Analysis.

Context: During the COVID-19 pandemic, both people with underlying diseases and previously healthy people were infected with SARS-CoV-2. In our institute, most hospitalized patients underwent chest computed tomography (CT) to evaluate pulmonary involvement and complication of COVID-19. There are currently limited data regarding thyroid CT incidentalomas in healthy people. Objective: We aimed to investigate the prevalence and predictors of thyroid incidentalomas among hospitalized patients with COVID-19. Methods: A single-center retrospective study included hospitalized patients aged ≥15 years with COVID-19 who underwent chest CT during April 2020 and October 2021. Thyroid incidentalomas were reviewed and identified by an experienced radiologist. Logistic regression analysis was used to determine predictors for thyroid incidentalomas. Results: In the 1326 patients (mean age 49.4 years and 55.3% female) that were included, the prevalence of thyroid incidentalomas was 20.2%. Patients with thyroid incidentalomas were older (59.6 years vs 46.8 years, P < .001) and more often female than those without incidentalomas (63.4% vs 53.2%, P = .003). On multivariate analysis, only female sex (OR 1.56; 95% CI 1.17-2.07) and older age (OR 1.04; 95% CI 1.03-1.05) were significantly associated with thyroid incidentalomas. Conclusion: In COVID-19 patients, the prevalence of thyroid incidentalomas identified on chest CT was higher (20.2%) than in previous studies in the general population (<1% to 16.8%). Female sex and older age were independent factors associated with thyroid incidentalomas.

Intravoxel incoherent motion for differentiating residual/recurrent tumor from post-treatment change in patients with high-grade glioma.

PURPOSE: To investigate the diagnostic value of f derived from IVIM technique and to correlate it with rCBV derived from DSC for the differentiation of residual/recurrent tumor from post-treatment change in patients with high-grade glioma. MATERIALS AND METHODS: Patients who underwent MR imaging with IVIM and DSC studies for evaluation of high-grade glioma after standard treatment were enrolled in this retrospective study. For qualitative analysis, the f and rCBV maps were interpreted as hypoperfused or hyperperfused in each parameter. Quantitative analysis was performed using ROI analysis in f and rCBV parameters. The lesions were divided into residual/recurrent tumor and post-treatment change groups. RESULTS: Nineteen patients with high-grade glioma were included. In qualitative analysis, the f-map shows higher sensitivity (100.0%) than rCBV map (92.3%), while the rCBV map shows higher specificity (100.0%) than the f-map (83.3%). In quantitative analysis, the optimal cutoff values of 1.19 for f and 1.06 for rCBV are shown to provide high diagnostic value with high sensitivity (91.7%) for both parameters but slightly higher specificity of rCBV (85.7%) than f (71.4%). The correlation between f and rCBV was good with ICC of 0.810. CONCLUSION: The f value measured by IVIM technique, non-contrast perfusion technique, has high diagnostic performance and potential to be an alternative method to CBV measured by DSC for differentiation between residual/recurrent tumor and post-treatment change in patients with high-grade glioma.

Susceptibility-weighted imaging is helpful in diagnosis of cerebral gnathostomiasis.

PURPOSE: To describe the role of SWI compared with other MR imaging sequences and CT in diagnosis of cerebral gnathostomiasis. MATERIALS AND METHODS: CTs and MRIs of patients with cerebral gnathostomiasis were retrospectively reviewed. The types of intracranial hemorrhage, including intraparenchymal hemorrhage (IPH), subdural hemorrhage (SDH), subarachnoid hemorrhage (SAH), and their locations were recorded. RESULTS: Four patients proven as cerebral gnathostomiasis were included. Intracranial hemorrhage was detected in all patients. There was IPH in all patients, SAH in 2 patients, and SDH in 2 patients. All patients (4/4) revealed hemorrhagic tracts which were very conspicuously seen on SWI. Other imaging sequences could also reveal hemorrhagic tracts in 3 patients (3/4) but are less conspicuously seen than SWI. None of the CT brains could detect hemorrhagic tracts. CONCLUSIONS: Intracranial hemorrhage associated with hemorrhagic tract, best demonstrated by SWI, is the key imaging characteristic in diagnosis of cerebral gnathostomiasis.

Prevertebral fat in Madelung disease mimicking cervical spine injury: A case report.

Madelung disease is defined by multiple symmetric fatty accumulations, usually involving the upper trunk, and may sometimes have excessive fat deposition in the prevertebral space. On magnetic resonance imaging (MRI), findings of fat that are hyperintense on T1w and T2w images, may simulate subacute hematoma and mimic cervical spine injury. This is the first reported case of Madelung disease with prevertebral fat deposition mimicking prevertebral hematoma found in cervical spine injury on MRI. Fat suppression techniques are helpful in order to differentiate between these two conditions, which should be taken into consideration during routine clinical practice.

White matter: A good reference for the signal intensity evaluation in magnetic resonance imaging for the diagnosis of uveal melanoma.

BACKGROUND: Comparing the signal intensity (SI) of an ocular mass to that of the vitreous body has been suggested. Most ocular lesions show a hyper-intense signal compared to the vitreous body on T1-weighted (T1w) images, and malignant melanomas have been almost always determined as 'cannot be excluded' in reports. PURPOSE: This study aimed to determine the accuracy of magnetic resonance imaging (MRI) in the diagnosis of uveal melanoma by using normal white matter as reference tissue for SI evaluation on T1w images and vitreous body on T2w compared to the conventional method using the vitreous body as a reference on both T1w and T2w images. METHODS: The MRIs of 43 patients (between August 2006 and July 2018) sent to rule out uveal melanoma were blindly reviewed by two radiologists. By using white matter as a reference for SI evaluation on T1w images and vitreous body as a reference on T2w images, uveal melanomas were suggested by hyper-intense signal on T1w and hypo-intense signal on T2w with homogeneous enhancement. The accuracy of diagnosis of uveal melanoma using white matter as a reference on T1w was compared to the conventional method using the vitreous body as a reference on both T1w and T2w images. RESULTS: The diagnosis of uveal melanoma using white matter as a reference gave a sensitivity of 92.31% (95% confidence interval (CI) 63.97-99.81) and specificity of 100.0% (95% CI 88.43-100.0). By using the vitreous body as a reference, sensitivity as high as 100.0% (95% CI 100.0-100.0) was obtained, but specificity was low at 53.33% (95% CI 34.33-71.66). CONCLUSIONS: White matter is a good reference for the diagnosis of uveal melanoma, with high sensitivity and much higher specificity than conventional methods using the vitreous body as a reference.