Objectives: To investigate the impact of compressed sensing - sensitivity encoding (CS-SENSE) acceleration factor on the diagnostic performance of magnetic resonance imaging (MRI) within standard female pelvis protocol in patients with endometrial cancer. Methods: T2-weighted turbo spin echo (TSE) sequence from standard female pelvic MRI protocol was chosen due to its long acquisition time and essential role in the evaluation of morphological characteristics of the female pelvic anatomical structures. Fully sampled reference scans and multiple prospectively 2x to 5x under-sampled CS-SENSE scans were acquired. Retrospectively, under-sampled scans were compared to fully sampled scans and visually assessed for image quality and diagnostic quality by two independent radiologists dedicated to urogenital imaging with different experience levels. Results: Images obtained with CS-SENSE accelerated acquisition were of diagnostically acceptable quality at up to 3x acceleration for T2 TSE in both axial and sagittal planes (with an acquisition time reduction of 64 %). Among all evaluated uterine structures, the junctional zone proved to be most sensitive to the influence of the acceleration factor. Statistical analysis showed statistically significant differences between image interpretation qualities between two radiologists of different experience levels (p < 0.05). Conclusion: CS-SENSE accelerated T2 TSE sequence of the female pelvis shows image quality similar to that of conventional acquisitions with reduced acquisition time. CS-SENSE can moderately reduce scan time, providing many benefits without losing the image quality.
IntroductionMagnetic resonance imaging (MRI) with its innovative techniques, such as diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC), increases the diagnostic accuracy in distinguishing between malignant and benign lesions of the endometrium. The aim of the study was MRI differentiation between malignant and benign endometrial lesions and correlation with histopathological findings with a special emphasis on quantitative analysis. An additional aim was to correlate the ADC values and histological tumor grades.MethodsThe prospective study included 119 female patients with or without vaginal bleeding and pathological values of endometrial thickness, who underwent MRI examinations. According to MRI reports the patients were divided into 45 suspicious malignant and 74 suspicious benign endometrial lesions. The radiological diagnosis was compared to the histopathological evaluation, which confirmed 37 malignant lesions while the rest were benign.ResultsThe mean ADC value for malignant lesions was 0.761 ± 0.13×10−3 mm2/s and for benign lesions was 1.318 ± 0.20×10−3 mm2/s. The ADC values for malignant lesions were expectedly lower than those of benign lesions (p<0.001). The ADC cut-off value was 1.007×10−3 mm2/s with a sensitivity of 100%, specificity of 92.7%, a positive predictive value of 60.3%, and a negative predictive value of 100%. In comparison with the histopathological findings, the sensitivity of MRI was 100%, specificity 90.2%, positive predictive value was 82.2%, and negative predictive value was 100%. Observing the histological grades 1, 2, and 3 of endometrial carcinoma, no statistically significant differences of mean ADC values were found. The mean ADC values for histological tumor grades 1,2 and 3 were 0.803 ± 0.13×10−3 mm2/s, 0.754 ± 0.12×10−3 mm2/s and 0.728 ± 0.13×10−3 mm2/s, respectively.ConclusionDWI and ADC values represent clinically useful tools for the differentiation between malignant and benign endometrial lesions with high sensitivity and good specificity, but the results failed to demonstrate their usefulness in differentiating histological grades of endometrial cancer.
PURPOSE:To investigate the impact of compressed sensing - sensitivity encoding (CS-SENSE) acceleration factor on the diagnostic quality of magnetic resonance images within standard brain protocol. METHODS:Three routine clinical neuroimaging sequences were chosen for this study due to their long acquisition time: T2-weighted turbo spin echo (TSE), fluid - attenuated inversion recovery (FLAIR), and 3D time of flight (TOF). Fully sampled reference scans and multiple prospectively 2x to 5x undersampled CS scans were acquired. Retrospectively, undersampled scans were compared to fully sampled scans and visually assessed for image quality and diagnostic quality by three independent radiologists. RESULTS:Images obtained with CS-SENSE accelerated acquisition were of diagnostically acceptable quality at up to 3x acceleration for T2 TSE (average qualitative score 3.53 on a 4-point scale, with the acquisition time reduction of 64%), up to 2x for FLAIR (average qualitative score 3.27, with the acquisition time reduction of 43%) and 4x acceleration for 3D TOF sequence (average qualitative score 3.13, with the acquisition time reduction of 73%). There were no substantial differences between the readers' diagnostic quality scores (p > 0.05). CONCLUSIONS:CS-SENSE accelerated T2 TSE, FLAIR, and 3D TOF sequences of the brain show image quality similar to that of conventional acquisitions with reduced acquisition time. CS-SENSE can moderately reduce scan time, providing many benefits without losing the image quality.
ObjectiveInvestigation of functional magnetic resonance (MR) imaging role in early diagnosis of diabetic nephropathy (DN) in patients with diabetes mellitus (DM) type 2, by quantification of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values.Material and methods10 healthy volunteers and 91 DM type 2 patients were scanned using diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) sequences. Patients were divided into four groups based on the estimated glomerular filtration value (eGFR). ADC and FA values, calculated in six regions of interest in each kidney (cortex and medulla), were compared to eGFR and laboratory parameters of renal function.ResultsADC values of DM patients were higher in the cortex than in the medulla (p<0.01), while FA values were higher in the medulla (p=0.284). Creatinine, cystatin C negatively correlated with ADC (cortex, medulla, parenchyma). Medullary FA were lower in DM patients and positively correlated with the eGFR (p=0.049). Tractography showed disturbed structure in patients with impaired renal function.DiscussionMedullary FA value is a more sensitive parameter than parenchymal ADC in the early detection of renal damage in DM patients. ADC and FA values are significant in the diagnosis of DN; further research is needed for the update and refinement of the established recommendations.