Scoring system for predicting ovarian necrosis in adnexal torsion using an ultra-short optimized MRI protocol.

PURPOSE: To evaluate a MRI scoring system predicting haemorrhagic necrosis in adnexal torsion with intraoperative and/or histopathological correlation using an abbreviated and optimized MRI protocol. METHODS: This retrospective observational study includes patients with adnexal torsion who underwent Magnetic Resonance Imaging(MRI) and surgery. T2 sequences were evaluated by three observers of varying experience for following findings: Hypo-intensity of ovarian stroma, around the follicle, cyst wall or ovarian capsule and the twisted pedicle. Hypo-intensities in the above and a thick cyst wall were considered as predictors of necrosis. A scoring system was created based on the number of positive findings. MRI was correlated with intraoperative and histopathological findings. Lesions showing haemorrhagic necrosis were considered true positives. RESULTS: 43 women with torsion were included. 74.4% were secondary to a lead point and 25.4% were without one. Hypointensity score of 2 or more had the highest diagnostic accuracy and inter-reader agreement in predicting necrosis (R1-sensitivity: 92%, specificity: 89%, positive predictive value (PPV): 92% and negative predictive value (NPV): 89%, R2-sensitivity: 92%, specificity: 94%, PPV: 96% and NPV: 90% and R3-sensitivity: 92%, specificity: 83%, PPV: 89% and NPV: 89%). CONCLUSION: In patients with suspected adnexal torsion, optimized MRI using T2 weighted sequences will serve as a rapid and effective single imaging modality for diagnosing adnexal torsion and accurately predicting necrosis thereby triaging the patients for appropriate management.

Comparison of Ultrashort TE Lung MRI and HRCT Lungs for Detection of Pulmonary Nodules in Oncology Patients.

Purpose The purpose of this study is to evaluate the detection rate of pulmonary nodules in ultrashort echo time (UTE) lung magnetic resonance imaging (MRI) and to compare it with computed tomography (CT) in oncology patients. Materials and Methods All individuals undergoing radiotherapy/chemotherapy/regular follow-up or visiting the oncology department and referred to radiology department for nodule detection, during the period of 1 year, were subjected to UTE lung MRI using the sequence Flash 3d_spiralvibe coronal 1.25 mm iso and high-resolution CT lungs and the images were analyzed. Results Among the total number of nodules detected in both lungs of all patients, nodules detected by CT were 241, and nodules detected by MRI were 212. The nodule detection rate by MRI was 87.96%. The detection rate of nodules for size equal to or more than 5 mm was nearly 100%. For nodules less than 5 mm, and equal to or more than 4 mm, MRI showed a comparable detection rate of 75%, while for nodules less than 4 mm, the detection rate was only 25%. Conclusion Our study results indicate that lung MRI had a near-complete detection rate for nodules equal to or more than 5 mm in size. Hence, in oncology patients who are undergoing regular follow-up of the lung nodules, lung MRI using UTE can replace low-dose CT, which in turn reduces the radiation dose to the patient.

The role of third-generation dual-source dual-energy computed tomography in characterizing the composition of renal stones with infrared spectroscopy as the reference standard.

Purpose: The aim of our study was to prospectively evaluate the role of third-generation, dual-source, dual-energy computed tomography (DECT) in the characterization of renal calculi, with ex vivo renal stone evaluation using Fourier transform infrared spectroscopy (IS) as the reference standard. Material and methods: In our study 50 patients with history suggestive of renal calculi were subjected to DECT using 100 kVp and Sn150 kVp. With DECT, renal stone attenuation at low and high kVp was attained, and the attenuation ratios were measured. The result of DECT was compared with IS to identify the chemical composition of the extracted renal stones. IBM SPSS version 22 was used for statistical analysis. Results: In our study, the mean attenuation ratio of the renal stone was 1.57 ± 0.25. Out of 50 patients, the stones of 39 patients were predicted as calcium-containing stones, in 4 patients as cystine stones, and in 7 as uric acid stones on DECT. In IS analysis, 43 patients had calcium-containing stones, and 7 patients had uric acid stones. The accuracy rate of DECT for detecting calcium and uric acid stones in our study were 90% and 100%, respectively. The positive predictive value for the DECT to assess the chemical composition of renal calculi was found to be 92%. Conclusions: Third-generation DECT scan had 100% accuracy in differentiating uric acid stones from non-uric acid stones in our study. Because the treatment is different for different chemical compositions of stones, identification of specific chemical components is very important, and it can be accurately done by DECT.

Does dual-energy abdominal computed tomography increase the radiation dose to patients: a prospective observational study.

PURPOSE: The aim of our study was to compare single-energy (SECT) and dual-energy (DECT) abdominal computed tomography (CT) examinations in matched patient cohorts regarding the differences in effective radiation dose (ERD) and image quality performed in a third-generation dual-source computed tomography (DSCT) scanner. MATERIAL AND METHODS: Our study included 100 patients, who were divided randomly into 2 groups. The patients included in Group A were scanned by SECT, and Group B members were scanned by DECT. Volume CT dose index (CTDIvol), dose length product (DLP), and ERD for venous phase acquisition were recorded in each patient and were normalised for 40 cm. Analyses were performed by using statistical software (SPSS version 20.0 for windows), and Bonferroni correction for multiple comparisons was applied for p-values and confidence intervals. RESULTS: Average ERD based on DLP values normalised for 40 cm acquisition were obtained for both Group A and Group B. The mean ERD for Group A was 11.89 mSv, and for group B it was 6.87 mSv. There was a significant difference in these values between Group A and Group B as shown by a p-value of < 0.001. On subjective and objective analysis, there was no statistically significant difference in image quality between the 2 groups. CONCLUSIONS: The protocols in third-generation DSCT using dual-energy mode resulted in significant reductions in the effective radiation dose (by approximately 58%) compared to SECT in routine abdominal examination in matched cohorts. Therefore, the quantitative imaging potential of DECT can be utilised in needed patients with decreased radiation dose in third-generation DSCT.

Elastography: a surrogate marker of renal allograft fibrosis - quantification by shear-wave technique.

PURPOSE: Renal fibrosis is the most common cause of allograft failure in kidney transplantations. Evaluation of renal abnormalities has progressed considerably over the past years. Currently, the diagnosis of intrarenal fibrosis and quantification of its development with non-invasive assessment tools is possible. This may help in early detection of renal allograft dysfunction. This study sought to assess the efficacy of 2D real-time shear-wave elastography (SWE) in the quantitative measurement of renal allograft dysfunction. METHODS: A total of 172 patients were included in our study. SWE was performed in all these patients just before renal allograft biopsy. The cortical elasticity was assessed and described in terms of Young's modulus (kPa). Banff histopathological grading obtained from transplant kidney tissue biopsy was taken as the reference standard. The potential correlation between SWE scores and Banff classification was performed. RESULTS: There was a significant correlation between the Banff grade and mean SWE score, with a correlation coefficient of 0.665 (p < 0.001). The individual correlation coefficients of interstitial fibrosis and tubular atrophy with mean SWE score stood at 0.667 and 0.649 respectively (p < 0.001). The correlation of resistive indices was insignificant when compared to mean polar SWE score in respective poles and the Banff grading of fibrosis. CONCLUSIONS: Renal stiffness quantified by 2D SWE showed significant correlation with histopathological renal fibrosis. Thus, the study suggests that shear-wave elastography could be used as a surrogate marker for early detection of renal fibrosis.