Correlation of clinical, laboratory, and short-term outcomes of immunocompromised and immunocompetent COVID-19 patients with semi-quantitative chest CT score findings: A case-control study.

BACKGROUND: As the effects of immunosuppression are not still clear on COVID-19 patients, we conducted this study to identify clinical and laboratory findings associated with pulmonary involvement in both immunocompromised and immunocompetent patients. METHODS: A case-control of 107 immunocompromised and 107 immunocompetent COVID-19 patients matched for age and sex with either positive RT-PCR or clinical-radiological findings suggestive of COVID-19 enrolled in the study. Their initial clinical features, laboratory findings, chest CT scans, and short-term outcomes (hospitalization time and intensive care unit [ICU] admission) were recorded. In addition, pulmonary involvement was assessed with the semi-quantitative scoring system (0-25). RESULTS: Pulmonary involvement was significantly lower in immunocompromised patients in contrast to immunocompetent patients, especially in RLL (p = 0.001), LUL (p = 0.023), and both central and peripheral (p = 0.002), and peribronchovascular (p = 0.004) sites of lungs. Patchy (p < 0.001), wedged (p = 0.002), confluent (p = 0.002) lesions, and ground glass with consolidation pattern (p < 0.001) were significantly higher among immunocompetent patients. Initial signs and symptoms of immunocompromised patients including dyspnea (p = 0.008) and hemoptysis (p = 0.036), respiratory rate of over 25 (p < 0.001), and spo2 of below 93% (p = 0.01) were associated with higher pulmonary involvement. Total chest CT score was also associated with longer hospitalization (p = 0.016) and ICU admission (p = 0.04) among immunocompromised patients. CONCLUSIONS: Pulmonary involvement score was not significantly different among immunocompromised and immunocompetent patients. Initial clinical findings (dyspnea, hemoptysis, higher RR, and lower Spo2) of immunocompromised patients could better predict pulmonary involvement than laboratory findings.

A case report on pulmonary metastasis of giant cell tumor mimicking arteriovenous malformation.

Giant cell tumor (GCT) is typically a benign tumor of the skeletal system that mainly presents with bone pain. Pulmonary metastasis is one of the distant presentations of GCT in patients who have previously undergone surgical resection of the tumor. Among the various presentations of pulmonary metastasis in GCT, lesions with arteriovenous malformation (AVM) features are rare and have only been reported in a few cases. In this case report, we present the case of a 29-year-old female patient who had previously undergone surgical resection of a GCT in her right lower extremity 4 years ago. The patient was referred to us with progressive dyspnea, and a lesion resembling an AVM was found during radiologic evaluation using chest computed tomography. Pathologic evaluation of the lesion after biopsy revealed that it was a metastasis of GCT presenting with vascular-like features in the lung. This study reports on a very rare occurrence of GCT pulmonary metastasis with an AVM appearance on imaging, highlighting the clinical importance of atypical presentations of pulmonary metastasis in patients with a history of GCT. Appropriate and timely screening and management of such lesions may prevent adverse outcomes such as massive hemorrhage and deterioration of lung function.

Texture analysis on routine MRI sequences to differentiate between focal nodular hyperplasia and hepatocellular adenoma.

Purpose: We investigated the diagnostic power of texture analysis (TA) performed on MRI (T2-weighted, gadolinium-enhanced, and diffusion-weighted images) to differentiate between focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA). Material and methods: This was a retrospective single-centre study. Patients referred for liver lesion characterization, who had a definitive pathological diagnosis, were included. MRI images were taken by a 3-Tesla scanner. The values of TA parameters were obtained using the ImageJ platform by an observer blinded to the clinical and pathology judgments. A non-parametric Mann-Whitney U test was applied to compare parameters between the 2 groups. With receiver operating characteristic (ROC) analysis, the area under the curve (AUC), sensitivity, and specificity were calculated. Finally, we performed a binary logistic regression analysis. A p-value <0.05 was reported as statistically significant. Results: A total of 62 patients with 106 lesions were enrolled. T2 hyperintensity, Atoll sign, and intralesional fat were encountered more in HCAs, and central scars were more frequent in FNHs. Multiple TA features showed statistically significant differences between FNHs and HCAs, including skewness on T2W and entropy on all sequences. Skewness on T2W revealed the most significant AUC (0.841, good, p < 0.0001). The resultant model from binary logistic regression was statistically significant (p < 0.0001) and correctly predicted 84.1% of lesions. The corresponding AUC was 0.942 (excellent, 95% CI: 0.892-0.992, p < 0.0001). Conclusion: Multiple first-order TA parameters significantly differ between these lesions and have almost fair to good diagnostic power. They have differentiation potential and can add diagnostic value to routine MRI evaluations.

Diffuse Neurobrucellosis of Cerebellum, Brainstem, Spinal Cord, and Cauda Equina: A case report and Literature review.

Neurobrucellosis is an uncommon serious complication of brucellosis. Diagnosis of neurobrucellosis could be difficult due to non-specific clinical and radiological findings. So, in endemic regions, neurobrucellosis should be included in the differential diagnosis list of patients with recent neurological disorders. We report an unusual case of neurobrucellosis with neurologic deficits in the central and peripheral nervous system and MRI lesions in the brainstem, spinal cord, and nerve roots Also, related articles are reviewed in the discussion section.

Assessing the short-term effects of radiotherapy on the shear modulus of the common carotid artery as a new biomarker of radiation-induced atherosclerosis.

PURPOSE: The purpose of this study was to investigate the incidence of short-term atherosclerosis in the common carotid arteries following radiotherapy. METHODS: The mean radiation dose to the arteries was 49.30±15.83 Gy. A computational ultrasound method was introduced to investigate the elastic modulus. Ultrasonography was performed 2-3 cm inferior to the bifurcation region before and after radiotherapy, and sequential images were extracted from a video of each artery. Instantaneous movement of the arterial wall in the radial and longitudinal directions was extracted by implementing the maximum gradient and block matching algorithms, respectively. RESULTS: There was a significant change in systolic blood pressure after radiotherapy (P=0.008). Irradiated arteries had significantly smaller systolic and end-diastolic diameters than non-irradiated arteries (P<0.001). The shear modulus was significantly different between irradiated and non-irradiated arteries (3.10±2.03 kPa vs. 1.38±0.98 kPa, P<0.001). The shear and Young moduli of radiation-induced arteries were 2.25±1.50 and 1.57±0.59 times higher than those of the pre-irradiation arteries. CONCLUSION: The arterial shear modulus can be considered as a new biomarker of radiationinduced atherosclerosis in the common carotid artery.

Predictors of the chest CT score in COVID-19 patients: a cross-sectional study.

BACKGROUND: Since the COVID-19 outbreak, pulmonary involvement was one of the most significant concerns in assessing patients. In the current study, we evaluated patient's signs, symptoms, and laboratory data on the first visit to predict the severity of pulmonary involvement and their outcome regarding their initial findings. METHODS: All referred patients to the COVID-19 clinic of a tertiary referral university hospital were evaluated from April to August 2020. Four hundred seventy-eight COVID-19 patients with positive real-time reverse-transcriptase-polymerase chain reaction (RT-PCR) or highly suggestive symptoms with computed tomography (CT) imaging results with typical findings of COVID-19 were enrolled in the study. The clinical features, initial laboratory, CT findings, and short-term outcomes (ICU admission, mortality, length of hospitalization, and recovery time) were recorded. In addition, the severity of pulmonary involvement was assessed using a semi-quantitative scoring system (0-25). RESULTS: Among 478 participants in this study, 353 (73.6%) were admitted to the hospital, and 42 (8.7%) patients were admitted to the ICU. Myalgia (60.4%), fever (59.4%), and dyspnea (57.9%) were the most common symptoms of participants at the first visit. A review of chest CT scans showed that Ground Glass Opacity (GGO) (58.5%) and consolidation (20.7%) were the most patterns of lung lesions. Among initial clinical and laboratory findings, anosmia (P = 0.01), respiratory rate (RR) with a cut point of 25 (P = 0.001), C-reactive protein (CRP) with a cut point of 90 (P = 0.002), white Blood Cell (WBC) with a cut point of 10,000 (P = 0.009), and SpO2 with a cut point of 93 (P = 0.04) was associated with higher chest CT score. Lung involvement and consolidation lesions on chest CT scans were also associated with a more extended hospitalization and recovery period. CONCLUSIONS: Initial assessment of COVID-19 patients, including symptoms, vital signs, and routine laboratory tests, can predict the severity of lung involvement and unfavorable outcomes.

The piriformis abscess: a case-based review.

This study reports a 43 years-old man diagnosed with piriformis pyomyositis. A literature review was conducted by searching MEDLINE via Pubmed for English language case reports, published from 8th December 2019 to 20th January 2020. Patients' symptoms, laboratory tests, imaging, treatment, and other comorbidities were evaluated. Thirty-two cases diagnosed with piriformis pyomyositis, of which 21 patients developed piriformis abscess (including one new patient added by us) of which 52.4% were female, and the mean age was 26.98 ± 17.5. The most common manifestations were fever, lower back pain, and limited ambulation with increased ESR, CRP, or leukocytosis. Staphylococcus aureus was the most prevalent (57.14%) pathogen isolated. The authors suggested gynecologic manipulations, muscle overuse, and other co-infections as probable risk factors. However, we fail to find any association between these factors and abscess formation (p>0.05). Piriformis abscess should be regarded as a probable diagnosis in patients with gluteal pain, fever, and limited ambulation that have raised inflammatory markers or leukocytosis. MRI and CT scans are beneficial in diagnosing pyomyositis in early-stage. Full recovery is expected with timely antibiotic and surgical treatments.

Pancreatic Neuroendocrine Tumor presenting as a diffuse pancreatic enlargement, case report and review of literature.

Pancreatic neuroendocrine tumors are rare neoplasms that comprise 1-2% of all pancreatic tumors. However, they are the second most common solid pancreatic neoplasms. They have a wide range of imaging appearances and they can show common to very rare imaging presentations. Most of the time they are solitary well-marginated enhancing solid mass arising in a certain aspect of the pancreas. We present a case report of a 41-year-old female who underwent clinical work-up for abdominal pain, loss of appetite and weight loss for the past year. Ultrasound, computed tomography, and magnetic resonance imaging show diffuse homogenous pancreatic enlargement without contour deformity or a focal mass. Lymphoma and autoimmune pancreatitis were suggested based on imaging findings but IGg4 level and other lab data were normal. Endoscopic ultrasonography confirmed the diffuse enlargement of the pancreas without peripheral structures involvement. The pathological results of multiple fine-needle aspiration biopsy from all parts of the enlarged pancreas revealed a low-grade neuroendocrine tumor.

CT-scan findings of COVID-19 pneumonia based on the time elapsed from the beginning of symptoms to the CT imaging evaluation: a descriptive study in Iran.

Background. Coronavirus disease 2019 (COVID-19) was initially detected in Wuhan city, China. Chest CT features of COVID-19 pneumonia have been investigated mostly in China, and there is very little information available on the radiological findings occurring in other populations. In this study, we aimed to describe the characteristics of chest CT findings in confirmed cases of COVID-19 pneumonia in an Iranian population, based on a time classification.Methods. Eighty-nine patients with COVID-19 pneumonia, confirmed by a real-time RT-PCR test, who were admitted to non-ICU wards and underwent a chest CT scan were retrospectively enrolled. Descriptive evaluation of radiologic findings was performed using a classification based on the time interval between the initiation of the symptoms and chest CT-scan.Results. The median age of patients was 58.0 years, and the median time interval from the onset of symptoms to CT scan evaluation was 7 days. Most patients had bilateral (94.4%) and multifocal (91.0%) lung involvement with peripheral distribution (60.7%). Also, most patients showed involvement of all five lobes (77.5%). Ground-glass opacities (GGO) (84.3%) and mixed GGO with consolidation (80.9%) were the most common identified patterns. We also found that as the time interval between symptoms and CT scan evaluation increased, the predominant pattern changed from GGO to mixed pattern and then to elongated-containing and band-like-opacities-containing pattern; on the other hand, the percentage of lung involvement increased.Conclusions. Bilateral multifocal GGO, and mixed GGO with consolidation were the most common patterns of COVID-19 pneumonia in our study. However, these patterns might change according to the time interval from symptoms.

Multimodality treatment in unresectable cholangiocarcinoma.

PURPOSE: Cholangiocarcinomas (CCs) are rare and highly malignant cancers. Although there are different treatment protocols for treatment of cholangiocarcinoma, we aimed to investigate a survival rate of patients with unresectable extrahepatic CCs (ECCs) receiving multimodality therapeutic protocol (MTP) (biliary drainage + external beam radiotherapy [EBRT] + brachytherapy and systemic chemotherapy). Similarly, we aimed to identify a relationship between survival time and associated factors in treatment outcome. MATERIAL AND METHODS: This retrospective study was performed on patients with ECC, who were referred to our university hospital between 2012 and 2015, and their imaging were diagnosed as unresectable. Patients underwent MTP including internal-external drainage catheter (F10-12) with insertion under fluoroscopy guidance, EBRT with 25-28 fractions and concurrent chemotherapy using capecitabine (Xeloda) 825 mg/m2 at the days of radiotherapy, followed by brachytherapy (BT) with iridium-192 (192Ir) or cobalt-60 (60Co) sources for 21 Gy in 3 consecutive days. Demographic variables, complications, laboratory tests, imaging findings, and survival time (OS - overall survival after diagnosis; CS - survival after catheter placement) were recorded. RESULTS: A total of 38 patients, with mean SD age = 58.08 (9.80) years, male = 22 (57.9%), were evaluated. According to Bismuth-Corlette classification, 15 (39.5%) were in stage IIIA, 5 (13.2%) were in stage IIIB, 10 (26.3%) were in stage IV, and 8 (21.2%) were undefined. Of those, 21 (55.3%), 15 (39.5%), and 17 (44.7%) were involved with liver parenchyma, great vessels, and regional lymph nodes, respectively. Mean SD of OS was 15.11 (8.10) months (median = 15; 95% CI: 13.25-16.69), and CS was 2-29 months (mean SD = 11.71 (7.29); median = 10; 95% CI: 10.05-13.37). Further analysis revealed a considerable decrease in OS and CS in those with an involvement of liver parenchyma, great vessels, regional lymph nodes, and Bismuth type IV. CONCLUSIONS: Multimodality therapeutic approach in patients with inoperable ECCs could definitely improve their survival time and decrease complications. Survival time is significantly depending on tumor staging, gender, and involvement of liver parenchyma, great vessels, and regional lymph nodes.

A 41-year-old female with progressive multifocal leukoencephalopathy after liver transplant.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease caused by JC virus reactivation. Its occurrence is very rare after solid organ transplantation, especially liver transplantation. We report a patient who received liver transplantation due to liver failure resulting from autoimmune hepatitis and advanced PML presenting with aphasia. A 41-year-old female with a history of liver transplantation who received a usual immunosuppression regimen was admitted with a stroke attack resulting in right hemiplegia 2 months after liver transplantation. Surprisingly, she gradually developed dysarthria and left central facial paresis. A brain MRI showed an abnormal multifocal area with a high T2/flair signal in the deep subcortical white matter of the left hemisphere as well as the splenium of the corpus callosum. PCR evaluation of CSF for JCV was positive while other PCR results were negative. A liver transplant recipient receiving immunosuppressive treatment for a long time could develop PML due to JCV reactivation. Only eight cases of JCV infection were reported after liver transplantation by the time of reporting this case. Unfortunately, there is no definite treatment for PML.

Design and Validation of Synchronous QCT Calibration Phantom: Practical Methodology.

INTRODUCTION: Quantitative computed tomography (QCT) can supplement dual x-ray absorptiometry by enabling geometric and compartmental bone assessments. Whole-body spiral CT scanners are widely available and require a short scanning time of seconds, in contrast to peripheral QCT scanners, which require several minutes of scanning time. This study designed and evaluated the accuracy and precision of a homemade QCT calibration phantom using a whole-body spiral CT scanner. MATERIALS AND METHODS: The QCT calibration phantom consisted of K2HPO4 solutions as reference. The reference material with various concentrations of 0, 50, 100, 200, 400, 1000, and 1200 mg/cc of K2HPO4 in water were used. For designing the phantom, we used the ABAQUS software. RESULTS: The phantoms were used for performance assessment of QCT method through measurement of accuracy and precision errors, which were generally less than 5.1% for different concentrations. The correlation between CT numbers and concentration were close to one (R2 = 0.99). DISCUSSION: Because whole-body spiral CT scanners allow central bone densitometry, evaluating the accuracy and precision for the easy to use calibration phantom may improve the QCT bone densitometry test. CONCLUSION: This study provides practical directions for applying a homemade calibration phantom for bone mineral density quantification in QCT technique.