Genotoxic and Cytotoxic Effects of Cone Beam Computed Tomography and Multidetector Computed Tomography on Exfoliated Buccal Epithelial Cells.

Background: Cone beam computed tomography (CBCT) and multidetector computed tomography (MDCT) are frequently used in dental and maxillofacial problems. This study aimed to assess the genotoxicity and cytotoxicity effects of CBCT and MDCT radiographies on exfoliated buccal epithelial cells during dental examinations. Methods: This prospective experimental study was conducted at Babol University of Medical Sciences (Babol, Iran) from March 2021 to April 2021. Buccal mucosa smears were collected bilaterally pre-exposure and 12 days after CBCT or MDCT examinations. To compare the frequency of micronuclei and other cytotoxic cellular changes such as pyknosis, karyolysis, and karyorrhexis, the paired sample t test and Wilcoxon test were used. In addition, independent sample t test, Mann-Whitney, and Chi square tests were used to investigate the differences between the imaging methods and between men and women. All statistical analyses were performed using the SPSS software, and P≤0.05 was considered statistically significant. Results: The current study included 60 adult patients (30 patients in each group), ranging in age from 21 to 50 years. The micronuclei and the other cytotoxic cellular changes increased significantly after CBCT and MDCT radiographic examinations on the 12th day compared to the pre-exposure results (P<0.001). MDCT had statistically higher cytotoxic and genotoxic effects than CBCT (9.4%, 23.1%, and 40% higher values in micronucleus frequency, the mean frequency of micronuclei, and other cytotoxic changes, respectively). There were no significant differences between men and women in the two examination methods (P=0.46 and P=0.49, respectively). Conclusion: Dental examinations with CBCT and MDCT can increase cytotoxicity and chromosomal damage in both men and women. Due to its lower radiation toxicities, CBCT can be recommended as an alternative to MDCT for dental examinations.

Performance of European Thyroid Imaging Reporting and Data System in Stratifying Malignancy Risk of Thyroid Nodules: A Prospective Study.

Background: There is a limited number of studies reporting the performance of European Thyroid Imaging Reporting and Data System (EU-TIRADS) guideline in identifying thyroid nodule malignancy. We aimed to evaluate diagnostic accuracy of EU-TIRADS regardless of thyroid nodule size. Methods: During August 2019-November 2021, subjects with thyroid nodules were prospectively included. Sonographic characteristics were recorded and scored as per EU-TIRADS guideline. Finally, fine-needle aspiration (FNA) was performed, and cytological findings were reported. Results: Totally, 1266 thyroid nodules from 984 subjects were assessed, of which 295 nodules were smaller than 10 mm and 971 nodules were 10 mm or larger. Among nodules <10 mm, prevalence rates of malignancy for EU-TIRADS classes 2-5 were 0.0%, 3.7%, 20.6%, and 40.9%, respectively; these rates among nodules ≥10 mm were 2.3%, 4.0%, 19.3%, and 43.2%, respectively. The accuracy values of EU-TIRADS class 5 and EU-TIRADS class 4 or 5 in diagnosis of malignancy for nodules <10 mm were 86.4% and 79.7%, respectively; these rates for nodules ≥10 mm were 83.8% and 76.3%, respectively. Hypoechogenicity, microcalcification, ill-defined and irregular margins were predictors for malignancy regardless of thyroid nodule size. Conclusion: EU-TIRADS could provide an acceptable malignancy risk stratification that is helpful for better distinguishing benignity from malignancy, as well as preventing unnecessary FNA biopsies, in thyroid nodules irrespective of their size.

Association between Influenza vaccination and severity of lung involvement at CT images of the patients with COVID-19 infection: an Iranian retrospective case-control study.

Background: Frequent waves of corona virus disease (COVID-19) and lack of specific drugs against that, warrant studies to reduce the morbidity and mortality of this pandemic disease. In this study, we investigated the association between influenza vaccination and the severity and outcome of COVID-19 disease in Iranian patients living in the North. Methods: This retrospective case-control study was performed on186 patients with COVID-19 infection between March and April, 2020. Patients with positive PCR were divided into two groups of case and control; Patients with moderate to severe and normal to mild lung involvement, respectively. The lung opacities in all of the 5 lobes were evaluated on chest CT images using a CT severity scoring system. The history of influenza vaccination during the fall of 2019-2020 was determined by a phone call. Statistical analysis was done using the chi-square test, student's t-test, and logistic regression. The significance level was p<0.05. Results: The mean age of patients was 54.67±15.05years. Most patients had pulmonary manifestations including ground-glass opacity (57%), consolidation (80%) and pleural effusion (3.2%). Adjusting for age, gender, and history of underlying disease, vaccination is an effective factor in the severity of pulmonary involvement (AOR=0.39; 95%CI: (0.21, 0.73); P=0.003). Furthermore, the chance of ICU admission decreased via influenza vaccination (OR=0.21, P=0.001). Conclusion: The results showed that the severity of COVID-19 pulmonary involvement and outcome as ICU admission, and severe symptoms in patients with history of influenza vaccination were significantly lower than those without history of vaccination. This strategy can be used to prevent and reduce the complications of COVID-19.

Diagnostic performance of ACR-TIRADS, Korean TIRADS, and American Thyroid Association guidelines for risk stratification of thyroid nodules: a prospective study.

BACKGROUND: In the present study, the first aim was to compare the accuracy of three guidelines in the diagnosis of thyroid nodule malignancy. The second purpose was to find sonographic features potentially associated with the risk of malignancy. METHODS: In this cross-sectional study, we prospectively recruited patients referred with a diagnosis of thyroid nodule (≥ 1 cm) for fine-needle aspiration (FNA). Sonographic features were recorded and scored according to the American Thyroid Association (ATA-2015), the American College of Radiology-Thyroid Imaging Reporting and Data System (ACR-TIRADS), and the Korean TIRADS (K-TIRADS). FNA was conducted and cytological findings were reported. RESULTS: A total of 984 thyroid nodules were ultimately included, of which 144 (14.6%) were malignant and 840 (85.4%) were benign. The accuracy of ACR-TIRADS categories TR5 and TR4/5 was 88.3% and 69.3%, respectively. This rate for ATA-2015 classes High suspicion and Intermediate suspicion/High suspicion was 87.9% and 80.4%, respectively. For K-TIRADS classes 5 and 4/5, the diagnostic accuracy was 88.0% and 80.6%, respectively. The rate of unnecessary FNA was highest with ATA-2015 and K-TIRADS guidelines (53.9% and 53.7%, respectively), followed by ACR-TIRADS (32.0%). Significant direct associations were observed between malignancy and hypoechogenicity (odds ratio [OR] 5.78), fine calcification (OR = 6.7), rim calcification (OR = 2.56), ill-defined margin (OR = 3.31), and irregular margin (OR = 6.95). CONCLUSIONS: There are different strengths of ACR-TIRADS, K-TIRADS, and ATA-2015 guidelines in the prediction of malignant thyroid nodules, and clinicians and radiologists should consider these differences in the management of thyroid nodules.

Role of scaling combination of risk factors in clinical and imaging findings during pregnancy in predicting placenta accreta spectrum.

BACKGROUND: Placenta accreta is one of the known causes of maternal mortality and morbidity. If diagnosed before delivery, appropriate actions can be taken. The aim of this study was to investigate the role of scaling combination of risk factors in predicting placenta accreta spectrum (PAS). METHODS: In this cross-sectional study, 120 pregnant women with two criteria and more of placenta previa in their ultrasound, underwent MRI. Clinical scores (history of surgery, cesarean section, previa, etc.) and paraclinical scores (ultrasound and MRI) were recorded and combined. In cases of hysterectomy, pathological examination was performed. The results were compared and analyzed using SPSS Version 22. The significance level was less than 0.05. RESULTS: Of the120 studied patients, 90 (75%) women were diagnosed with placenta previa in which, 32(36%) patients had placenta accreta and 12 patients had placenta accreta without placenta previa. The mean ultrasound score in women without and with placenta accreta were 0.05±0.32 and 2.43±1.83 (p<0.001). The mean MRI score in women without and with placenta accreta were 0.05±0.27 and 2.07±2.02, respectively. The cut-off point, sensitivity and specificity were 0.50, 100% and 93.4%, respectively. The mean clinical score without and with placenta accreta were 1.97±1.32 and 4.89±3.21, respectively. The cut-off point, sensitivity and specificity were 2.50, 70% and 80%, respectively. The cut-off point of combination score, sensitivity and specificity were 3.50, 89%, 83%. CONCLUSION: The results of the present study showed that the most specific test to confirm the definitive diagnosis of placenta accreta is paraclinical score, alone.

Accuracy of mammography and ultrasonography and their BI-RADS in detection of breast malignancy.

BACKGROUND: We aimed to compare the diagnostic accuracy of mammography and ultrasonography and their breast imaging-reporting and data system (BI-RADS) classification versus breast core needle biopsy (CNB) findings in distinguishing the breast masses. METHODS: This cross-sectional study was conducted during 2016-2018 on female patients who were referred to a radiology center in Babol, northern Iran, for routine screening and/or for CNB. Patients underwent sonography and mammography by a senior radiologist. The breast lesions were also evaluated according to BI-RADS classification. CNB was performed on the breast masses by the same radiologist and pathological procedures were performed by an expert pathologist. Descriptive statistics were used to analyze the data. RESULTS: In total, 213 breast masses were finally assessed, of which 107 (50.2 %) masses were benign and 106 (49.8 %) masses were malignant. The sensitivity for mammography and ultrasound alone was 72.6% and 68.9%, respectively. This rate for combined mammography and ultrasound was 84.9%. About BI-RADS classification, 28 masses were classified as BI-RADS 3, 99 as BI-RADS 4A, 4 as BI-RADS 4B, 18 as BI-RADS 4C, and 64 as BI-RADS 5. BI-RADS 4A had the highest sensitivity (70.1%) among BI-RADS categories. The highest specificity pertained to BI-RADS 3 and 5 (100%) among BI-RADS categories. Also, the highest accuracy was related to BI-RADS 5 (80.3%). CONCLUSION: The results of the present study showed that combined mammography and ultrasound had a higher rate of accuracy than mammography or ultrasound alone. Furthermore, the imaging methods BI-RADS classification had an acceptable positive predictive value.

Different sonographic features of peripheral thyroid nodule calcification and risk of malignancy: a prospective observational study.

PURPOSE: To investigate the association of peripheral calcification, as well as its sonographic features, with thyroid nodule malignancy. MATERIAL AND METHODS: This study was prospectively conducted during 2015-2020 on patients diagnosed with thyroid nodule undergoing ultrasound-guided fine-needle aspiration in Shahid Beheshti teaching hospital or private offices in Babol, northern Iran. The ultrasonographic characteristics of the nodules, as well as the cytological findings, were recorded. Regression analysis was used to assess the relationship between sonographic results and malignancy. We also used receiver operator characteristics (ROC) analysis to estimate the ability of ultrasound to predict the characteristic features of malignancy, as estimated by the area under the curve (AUC). RESULTS: A total of 1857 thyroid nodules were finally included, of which 84 were peripherally calcified nodules. There was a significant positive association between the nodule malignancy and peripheral calcification (OR = 2.23, 95% CI: 1.13-4.35). In the nodules with peripheral calcification, significant positive associations were seen between malignancy and lobulated margin (OR = 3.85, 95% CI: 1.02-14.54) and solid composition (OR = 4.05, 95% CI: 0.99-16.53). The ROC analysis indicated that AUC for lobulated margin and solid composition was 63.8% and 66.5%, respectively, in predicting malignant thyroid nodules. CONCLUSION: The findings showed that peripheral calcification on sonography can be a potential indicator of malignant thyroid nodules. Also, the presence of lobulated margin and/or solid composition, besides peripheral calcification, can be helpful in better distinguishing malignant from benign nodules.

Delayed phases of contrast MRI, can it be valuable in multiple sclerosis active phase diagnosis?

BACKGROUND: Observing the enhancing plaques in magnetic resonance imaging (MRI) is one of the most valuable diagnostic modalities in confirming the diagnosis of multiple sclerosis (MS), its recurrence and for better detection of active disease. Since active lesions discovery can improve designating diffusion in time diagnosis of MS and controlling disease activity, and there is not any definite time for delay image acquisition, therefore, the aim of the current study was to evaluate the enhancement of MS plaques in different delayed phases. METHODS: In this interventional study, after receiving written consent, 40 MS patients with at least one enhancing plaque in a previous MRI were evaluated in Babol Ayatollah Rouhani Hospital. Gadolinium was injected to all patients at the dose of 0.1 mg/kg, and MRI was taken at 5 and 15 minutes. The results were analyzed using SPSS 23. A p<0.05 was considered as significant level. RESULTS: The mean of plaque signal intensity was 1190.20 and 1349.60 at 5 and 15 min, respectively, and this difference was significant (p<0.001). Moreover, the mean of plaque total size was 5.16 cm and 7.04 cm at 5 and 15 min with significant difference, respectively (p<0.001). The mean of plaque number was 1.92 and 2.58 at 5 and 15 min, respectively, which was significantly different (P<0.001). CONCLUSION: The results indicated improvement in detection of MS plaques in images taken in the delayed phase compared to those in the early phase. The plaque intensity, size and number were significantly higher in the delayed phase (15 min), than early phase (5 min).

The comparison of accuracy of ultrasonographic features versus ultrasound-guided fine-needle aspiration cytology in diagnosis of malignant thyroid nodules.

PURPOSE: To compare the diagnostic accuracy of sonographic features with ultrasound-guided fine-needle aspiration (FNA) cytology in the detection of malignant thyroid nodules. METHODS: This analytical cross-sectional study was conducted on patients with the diagnosis of thyroid nodule, who underwent ultrasound-guided FNA in Shahid Beheshti teaching hospital, Babol, northern Iran, between 2015 and 2017. The characteristics of the nodules obtained from ultrasonography were recorded. Regression analysis was used to assess the relation between sonographic findings and malignancy. We also used a receiver operator characteristics analysis to estimate the ability of ultrasound to predict the characteristic features of malignancy, as estimated by the area under the curve. RESULTS: In total, 898 thyroid nodules were included in the study, of which 55 (6.1%) were malignant and 843 (93.9%) were benign. There were significant positive associations between malignancy and hypoechogenicity [odds ratio (OR) 3.577, 95% confidence interval (CI) 2.045-6.256], fine calcification (OR 5.849, 95% CI 2.642-12.949), irregular margin (OR 4.366, 95% CI 2.284-8.345) and taller-than-wide shape (OR 5.199, 95% CI 2.125-12.721). The overall accuracies of hypoechogenicity, irregular margin, taller-than-wide shape and fine calcification were 0.804, 0.729, 0.705 and 0.575, respectively. CONCLUSION: According to the present study, the use of ultrasonography (along with ultrasound-guided FNA) is very effective in the diagnosis, follow-up, and indication for surgery of a thyroid nodule.

Risk factors associated with aortic calcification in hemodialysis patients.

BACKGROUND: There are some uncertainties among the risk factors of vascular calcification in the hemodialysis patients. This study was planned to examine the association between abdominal aortic calcification and concerned biochemical parameters in hemodialysis patients. METHODS: In this cross- sectional study, 84 stable hemodialysis patients admitted on hemodialysis section of Shahid Beheshti Hospital in 2013 were enrolled after obtaining informed consent. Pre-dialysis venous blood samples were taken from patients to determine the amount of intact parathyroid hormone (iPTH), alkaline phosphatase (Alk.P), C - reactive protein (CRP), calcium (Ca) and phosphorus (P). Patients underwent abdominal CT scanning and ACI (ACI) was calculated. Statistical analysis was performed using SPSS Version 20. Chi-square, Kruskal Wallis and One Way ANOVA tests were used. P-values < 0.05 were considered significant. RESULTS: The average age of participants was 50.15±17.03 years (18-83 y/o).A statistically significant correlation was observed between ACI and ALK-P serum levels (p=0.01). It was found that ACI had a significant relationship with phosphorus in women (p=0.01). ALK-P serum levels in men also had a significant relationship with ACI (p=0.02). In addition, there was a significant correlation between ACI and history of cerebro-cardiovascular disease and also duration of dialysis (p=0.004 and 0.0001, respectively). CONCLUSIONS: In patients with longer duration of dialysis, and patients with a history of cardiovascular and cerebrovascular events, ACI levels were significantly higher. ALK-P and phosphorus were correlated with aortic calcification in males and females respectively. No significant correlation was found between iPTH serum levels and aortic calcification.

Accuracy of densitometry of two cone beam computed tomography equipment in comparison with computed tomography.

BACKGROUND: The use of oral implants has been growing, and cone beam computerized tomography (CBCT) has become the method of choice for oral and maxillofacial radiology. OBJECTIVE: To assess the accuracy of bone densitometry in two different CBCT devices in comparison with MDCT (multi-detector CT). METHODS: Different concentrations of urografin, including 2.5%, 5%, 7.5%, 10%, 12.5%, were prepared, and the Hounsfield unit of these solution was measured by two CBCT devices (SORDEX CRANEX 3D and NEWTOM 5G) and one spiral CT device (SOMATOM SENSATION). Difference of output Hounsfield units in each concentration was compared in three devices. Correlation of devices with increase of urografin dose also was evaluated. Statistical analyses of the data were performed using SPSS18 and Kruskal-Wallis and Mann-Whitney U tests, along with Spearman's correlation coefficient. RESULTS: The range of gray density for NEWTOM 5G CBCT, SORDEX 3D CBCT, and SOMATOM CT imaging systems was from 781 to 2311, 427 to 1464, and 222 to 994, respectively. There was significant difference between devices in the Hounsfield unit in all urografin concentrations (p<0.001). Also there was a significant correlation between three devices with increasing the urografin dose (p<0.05; r>0.95). CONCLUSION: Our findings indicated a high correlation and linear relationship between different studied imaging systems. Although utilizing CBCT in the assessment of bone density is useful according to its lower emitted dose and less cost, clinicians should be aware of the issue that the voxel value in CBCT is not as perfect as CT.

ESTIMATION OF CARDIAC CT ANGIOGRAPHY RADIATION DOSE TOWARD THE ESTABLISHMENT OF NATIONAL DIAGNOSTIC REFERENCE LEVEL FOR CCTA IN IRAN.

In recent years, with the introduction of 64-slice CT and dual-source CT technology, coronary CT angiography (CCTA) has emerged as a useful diagnostic imaging modality as a non-invasive assessment of coronary heart disease. CT produces a larger radiation dose than other imaging tests and cardiac CT involves higher radiation dose with the advances in the spatial and temporal resolution. The aims of this study are patient dose assessment and establishment of national diagnostic reference level for CCTA in Iran. A questionnaire was sent to CCTA centers. Data for patient and CT protocols were obtained. The volumetric CT dose index (CTDIvol), dose length product (DLP) and total DLP were considered in the 32 cm standard body phantom. Calculation of estimated effective dose (ED) was obtained by multiplying the DLP by a conversion factor [k = 0.014 mSv (mGy·cm)-1]. Mean value of CTDIvol and DLP for CCTA was 50 mGy and 825 mGy·cm. The third quartile (75th) of the distribution of mean CTDIvol (66.54 mGy) and DLP (1073 mGy·cm) values was expressed as the diagnostic reference level (DRL) for CCTA in Iran. The median of ED was 10.26 mSv and interquartile range of ED was 7.08-15.03 mSv. A large variety in CTDIvol and DLP among CT scanner and different sites due to variability in CT parameter is noted. It seems that training could help to reduce patient's dose.

A case of rhabdomyosarcoma of kidney mimicking nephroblastoma.

BACKGROUND: Rhabdomyosarcoma (RMS) is one of the common malignant tumors in infants and children, but it is extremely rare in the kidney. In this paper, we present a case of RMS the kidney of a child. CASE PRESENTATION: A 6-month old girl presented with agitation, low fever and abdominal distention which started 5 days ago. On physical examination, the infant had a large and firm soft tissue mass in the palpation of her abdomen. Plain abdominal x-ray, sonography and CT scan showed soft tissue mass and Doppler ultrasound demonstrated regions of vascular flow in mass. The abdominal mass was replaced and on pathological examination and immunohistochemistry the diagnosis was embryonal RMS. CONCLUSION: Rhabdomyosarcoma of the kidney should be considered in the differential diagnosis of children with huge abdominal mass.