Creating the freedom to thrive: Honoring the legacy of RSNA gold medalist, Deborah Levine, MD.

Awarded the Radiological Society of North America (RSNA) Gold Medal in 2018, Dr. Deborah Levine's research, journalism, and mentorship have left an indelible mark on the radiology field. Her work in ultrasound led to its use as the standard for monitoring benign adnexal cysts. She helped popularize obstetric magnetic resonance imaging (MRI) through her research on its use in placental accreta and fetal abnormalities, which led to the development of the 'Compendium of Fetal MRI' website. This work in research led naturally to a career in journalism, where she eventually became Senior Deputy Editor of Radiology and founded Radiology Select. Concurrently with her personal achievements, Dr. Levine has dedicated herself to the mentorship of her female trainees. She sought various leadership positions to learn more about and advocate for the promotion and support of female leadership in radiology departments. In many ways, Dr. Levine's career and work have transformed radiology as we know it today for both patients and physicians.

Magnetic resonance elastography: evaluation of new inversion algorithm and quantitative analysis method.

PURPOSE: To assess mean shear hepatic stiffness calculations using various region of interest (ROI) techniques, a new inversion algorithm, and a confidence threshold mask. METHODS: Seventy-three patients (49 with abnormal liver function tests/known chronic liver disease and 24 healthy liver transplant donors) underwent liver biopsy and magnetic resonance elastography (MRE). MRE data processed with the current inversion algorithm [multiscale direct inversion (MSDI)] was assessed using 2 ROI methods (single vs. triple). The data were then reprocessed using the new inversion algorithm (multimodel direct inversion [MMDI]) Hepatic stiffness calculations were performed using a single (70%) ROI method, with/without a 95% confidence threshold mask, and compared with MSDI. RESULTS: For MSDI, average stiffness difference between single and triple ROI methods was not statistically significant by the 2-sample t test [0.15 kilopascals (kPa); P = .77]. For the 2 algorithms, there was little difference in average stiffness measurements of MSDI and MMDI (mean, 0.32 kPa; 9%) using a confidence mask with good agreement [intraclass correlation coefficient (ICC), 0.986 (95% CI 0.975-0.994)]. Use of the confidence mask showed excellent consistency and less variance [ICC, 0.995 (95% CI 0.993-0.998)] compared to either the inter-observer or intra-observer freehand technique. CONCLUSION: MRE analysis showed no significant difference between the 2 freehand ROI techniques. With a 9% average kPa variance, stiffness measurements for MSDI and MMDI were also not significantly different. The use of the confidence mask reduces calculated stiffness variability, which impacts the use of MRE for assessing therapy response and initial/longitudinal assessment of chronic liver disease.

Magnetic resonance elastography can discriminate normal vs. abnormal liver biopsy in candidates for live liver donation.

PURPOSE: The aim of this study was to define liver shear stiffness by magnetic resonance elastography (MRE) that distinguishes normal from abnormal liver biopsy, especially when steatosis ≥20%, among potential live liver donors. METHODS: Baseline clinical, laboratory, imaging, MRE, and liver biopsy results were recorded. Using MRE, hepatic shear stiffness in kilopascals (kPa) was measured and compared to liver biopsy. Comparison between groups was done using χ(2) or Fisher's exact test for categorical variables and Wilcoxon test for continuous variables. Receiver operating characteristic (ROC) curve was calculated to assess diagnostic accuracy. Statistical significance was set at p < 0.05. RESULTS: 38 healthy adults were included. Liver biopsy was normal in 27 and abnormal in 11. ROC curve for MRE defined optimal cutoff at 2.6 kPa (sensitivity 0.72, specificity 0.85, AUC 0.81) to distinguish these 2 groups. Hepatic steatosis ≥20% on biopsy is a contraindication for liver donation in our center. We evaluated the ability of MRE to distinguish this degree of steatosis: 8 persons had steatosis ≥20% and were excluded from donation. ROC curve for MRE defined optimal cutoff at 2.82 kPa (sensitivity 0.88, specificity 1, AUC 0.98) to identify this group. CONCLUSIONS: Liver stiffness measured by MRE, even in the absence of liver fibrosis, can be useful in differentiating normal from abnormal liver histology, and most importantly in patients under evaluation for live liver donation, can very accurately distinguish those with complicated hepatic steatosis ≥20%, our cutoff for donation. In the future, MRE might provide supplementary information to make liver biopsy unnecessary in the donor evaluation process.

Magnetic resonance elastography (MRE) in assessing hepatic fibrosis: performance in a cohort of patients with histological data.

PURPOSE: The purpose of this study was to compare fibrosis seen on liver biopsy to MR elastography (MRE) stiffness measurements in normal controls and patients with abnormal transaminases and chronic liver disease. METHODS: The control group consisted of 22 healthy liver transplant donors who by definition had normal transaminases. The patient group (32 patients) was recruited from the Mayo Clinic Arizona hepatobiliary clinic over a 3-year span. All subjects underwent a liver biopsy as part of their evaluation and agreed to MRE within 35 days of biopsy. Non-parametric tests were used to compare the MRE-predicted liver fibrosis to the fibrosis noted on liver biopsy. RESULTS: Analysis included 54 subjects (32 patients with chronic liver disease and 22 healthy liver donor candidates). MRE median liver stiffness measurements increased per histologic liver fibrosis stage (one-way ANOVA p = 0.001), with significant correlation between increasing fibrosis stage and stiffness values. Median MRE for control group (2.13 kPa; mean = 2.3 ± 0.6 kPa) was significantly lower than for patient group (3.7 kPa; mean = 4.1 ± 2.1 kPa) (p = 0.003). Significantly, lower median stiffness was seen in zero-to-moderate (F0-2, n = 22) vs. severe fibrosis stages (F3-4, n = 10) 2.80 vs. 5.9 kPa, respectively (p < 0.05). Using a 3.7-kPa cut-off value, the predicted sensitivity and specificity for detecting F0-2 from F3-4 were 91% and 80%, respectively. CONCLUSIONS: Our analysis supports previous findings that MRE is a non-invasive and effective method for detection and assessment of liver fibrosis, particularly for discrimination between F0-2 stages and F3-4 stages. MRE may represent a valuable tool to finely discern hepatic fibrosis non-invasively.

Early Outcome of Prostate Intensity Modulated Radiation Therapy (IMRT) Incorporating a Simultaneous Intra-Prostatic MRI Directed Boost.

This study assessed the feasibility and outcomes of treating prostate cancer with intensity modulated radiotherapy (IMRT) incorporating a Magnetic Resonance Imaging (MRI) directed boost. Seventy-eight men received IMRT for localized prostate cancer. The entire prostate received 77.4Gy in 43 fractions and simultaneous intra-prostatic boosts (SIB) of 83Gy were administered to increase the dose to the MRI identified malignancy. In 16 (21%) patients, the MRI didn't detect a neoplasm and these patients received an SIB of 81Gy to the posterior prostate. Androgen Deprivation Therapy (ADT) was also administered to 32 (41%) patients. The 3-year rates of biochemical control, local control, distant control, and survival were 92%, 98%, 95%, and 95% respectively. While grade 1-2 toxicities were common, there were only 2 patients who suffered grade 3 toxicity. These patients developed strictures which were dilated resulting in improvement in symptoms such that both had grade 1-2 toxicity at last follow up examination. The results of this program of IMRT incorporating a MRI directed intra-prostatic boost suggest this technique is feasible and well tolerated. This technique appears to shift the therapeutic index favorably by boosting the malignancy to the highest dose without increasing the doses administered to the bladder and rectum.

Reducing radiation dose in CT enterography.

Computed tomographic (CT) enterography is a diagnostic examination that is increasingly being used to evaluate disorders of the small bowel. An undesirable consequence of CT, however, is patient exposure to ionizing radiation. This is of particular concern with CT enterography because patients tend to be young and require numerous follow-up examinations. There are multiple strategies to reduce radiation dose at CT enterography, including adjusting acquisition parameters, reducing scan length, and reducing tube voltage or tube current. The drawback to dose reduction strategies is degradation of image quality due to increased image noise. However, image noise can be reduced with commercial iterative reconstruction and denoising techniques. With a combination of low-dose techniques and noise-control strategies, one can markedly reduce radiation dose at CT enterography while maintaining diagnostic accuracy.