Design and Rationale for the Use of Magnetic Resonance Imaging Biomarkers to Predict Diabetes After Acute Pancreatitis in the Diabetes RElated to Acute Pancreatitis and Its Mechanisms Study: From the Type 1 Diabetes in Acute Pancreatitis Consortium.

ABSTRACT: This core component of the Diabetes RElated to Acute pancreatitis and its Mechanisms (DREAM) study will examine the hypothesis that advanced magnetic resonance imaging (MRI) techniques can reflect underlying pathophysiologic changes and provide imaging biomarkers that predict diabetes mellitus (DM) after acute pancreatitis (AP). A subset of participants in the DREAM study will enroll and undergo serial MRI examinations using a specific research protocol. The aim of the study is to differentiate at-risk individuals from those who remain euglycemic by identifying parenchymal features after AP. Performing longitudinal MRI will enable us to observe and understand the natural history of post-AP DM. We will compare MRI parameters obtained by interrogating tissue properties in euglycemic, prediabetic, and incident diabetes subjects and correlate them with metabolic, genetic, and immunological phenotypes. Differentiating imaging parameters will be combined to develop a quantitative composite risk score. This composite risk score will potentially have the ability to monitor the risk of DM in clinical practice or trials. We will use artificial intelligence, specifically deep learning, algorithms to optimize the predictive ability of MRI. In addition to the research MRI, the DREAM study will also correlate clinical computed tomography and MRI scans with DM development.

Introducing the American College of Radiology Appropriateness Criteria to Medical Students to Increase Appropriate Imaging Selection.

INTRODUCTION: Inappropriate radiological imaging contributes significantly to excessive healthcare expenditure and increased radiation exposure. The American College of Radiology (ACR) Appropriateness Criteria (AC) serves as an evidence-based resource to guide appropriate imaging utilization. However, knowledge and utilization of these guidelines is lacking in medical education. We introduce a short curriculum to teach medical students correct imaging selection and familiarize them with the ACR AC. METHODS: Medical students attended a two-part lecture series to learn appropriate imaging selection in common clinical scenarios and the ACR AC. Participants completed a pre- and post-test questionnaire, each consisting of a 10-item test assessing student familiarity with the ACR AC, comfortability in answering, and satisfaction with the curriculum. Improvement in student knowledge and confidence was assessed by statistical analysis using t-tests. RESULTS: Prior to the lecture series, 20.3% of students had no familiarity with the ACR AC, and 41.8% only had slight familiarity. Students demonstrated a statistically significant improvement in the knowledge assessment and in their level of comfort in choosing appropriate imaging modalities. After the lecture series, 97.2% of students responded they would use the ACR AC in the future, with 98.6% of them satisfied with the curriculum. DISCUSSION: This short curriculum is effective at (1) increasing student knowledge of appropriate radiological studies to order in common clinical encounters and (2) increasing student familiarity of the ACR AC. Further studies will be conducted to assess this curriculum's efficacy in the earlier years of medical school and for first-year residents.

Predicting the aggressiveness of peripheral zone prostate cancer using a fractional order calculus diffusion model.

PURPOSE: To evaluate the performance of parameters D, ß, µ from the Fractional Order Calculus (FROC) model at differentiating peripheral zone (PZ) prostate cancer (PCa) MATERIAL AND METHODS: 75 patients who underwent targeted MRI-guided TRUS prostate biopsy within 6 months of MRI were reviewed retrospectively. Regions of interest (ROI) were placed on suspicious lesions on MRI scans. ROIs were then correlated to pathological results based on core biopsy location. The final tumor count is a total: 23 of GS 6 (3 + 3), 36 of GS 7 (3 + 4), 18 of GS 7 (4 + 3), and 19 of GS ≥ 8. Diffusion-weighted imaging (DWI) scans were fitted into the FROC and monoexponential model to calculate ADC and FROC parameters: anomalous diffusion coefficient D, intravoxel diffusion heterogeneity ß, and spatial parameter µ. The performance of FROC parameters and ADC at differentiating PCa grade was evaluated with receiver operating characteristic (ROC) analysis. RESULTS: In differentiating low (GS 6) vs. intermediate (GS 7) risk PZ PCa, combination of (D, ß) provides the best performance with AUC of 0.829 with significance of p = 0.018 when compared to ADC (AUC of 0.655). In differentiating clinically significant (GS 6) vs. clinically significant (GS ≥ 7) PCa, combination of (D, ß, µ) provides highest AUC of 0.802 when compared to ADC (AUC of 0.671) with significance of p = 0.038. Stratification of intermediate (GS 7) and high (GS ≥ 8) risk PCa with FROC did not reach a significant difference when compared to ADC. CONCLUSION: Combination of FROC parameters shows greater performance than ADC at differentiating low vs. intermediate risk and clinically insignificant vs. significant prostate cancers in peripheral zone lesions. The FROC diffusion model holds promise as a quantitative imaging technique for non-invasive evaluation of PZ PCa.

Quartile histogram assessment of glioma malignancy using high b-value diffusion MRI with a continuous-time random-walk model.

The purpose of this study is to investigate the feasibility of using a continuous-time random-walk (CTRW) diffusion model, together with a quartile histogram analysis, for assessing glioma malignancy by probing tissue heterogeneity as well as cellularity. In this prospective study, 91 patients (40 females, 51 males) with histopathologically proven gliomas underwent MRI at 3 T. The cohort included 42 grade II (GrII), 19 grade III (GrIII) and 29 grade IV (GrIV) gliomas. Echo-planar diffusion-weighted imaging was conducted using 17 b-values (0-4000 s/mm2 ). Three CTRW model parameters, including an anomalous diffusion coefficient Dm , and two parameters related to temporal and spatial diffusion heterogeneity α and ß, respectively, were obtained. The mean parameter values within the tumor regions of interest (ROIs) were computed by utilizing the first quartile of the histograms as well as the full ROI for comparison. A Bonferroni-Holm-corrected Mann-Whitney U-test was used for the group comparisons. Individual and combinations of the CTRW parameters were evaluated for the characterization of gliomas with a receiver operating characteristic analysis. All first-quartile mean CTRW parameters yielded significant differences (p-values < 0.05) between pair-wise comparisons of GrII (Dm : 1.14 ± 0.37 µm2 /ms; α: 0.904 ± 0.03, ß: 0.913 ± 0.06), GrIII (Dm : 0.88 ± 0.21 µm2 /ms; α: 0.888 ± 0.01, ß: 0.857 ± 0.06) and GrIV gliomas (Dm : 0.73 ± 0.22 µm2 /ms; α: 0.878 ± 0.01; ß: 0.791 ± 0.07). The highest sensitivity, specificity, accuracy and area-under-the-curve of using the combinations of the first-quartile parameters were 84.2%, 78.5%, 75.4% and 0.76 for GrII and GrIII classification; 86.2%, 89.4%, 75% and 0.76 for GrIII and GrIV classification; and 86.2%, 85.7%, 84.5% and 0.90 for GrII and GrIV classification, respectively. Quartile-based analysis produced higher accuracy and area-under-the-curve than the full ROI-based analysis in all classifications. The CTRW diffusion model, together with a quartile-based histogram analysis, offers a new way for probing tumor structural heterogeneity at a subvoxel level, and has potential for in vivo assessment of glioma malignancy to complement histopathology.

Rare primary hepatic malignancies: A case-based review.

The two most common primary liver malignancies that radiologists encounter in clinical practice are hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). However, there are other less common primary hepatic malignancies that radiologists should be aware of. The correct radiographic and pathologic diagnosis of these entities have important treatment and prognostic implications. In this paper, we review a series of five cases that we have encountered in clinical practice at our institution that were initially thought to be HCC or ICC, but turned out to be a rarer primary hepatic malignancy. We will review the radiographic and pathologic characteristics of each of these rare primary hepatic malignancies as well as discuss the prognosis and treatment for each.

Uterine Carcinosarcoma: A Case Report and Literature Review.

Uterine carcinosarcomas are rare and extremely aggressive undifferentiated carcinomas which include both carcinomatous and sarcomatous elements. A 52-year-old female presented with heavy irregular menstrual bleeding for several years and new right elbow pain and swelling. Ultrasound and computed tomography showed a large uterine mass with regional and distant metastatic lymphadenopathy and suspicious findings of osseous metastasis to the right elbow. A biopsy confirmed uterine carcinosarcoma, and the patient underwent chemotherapy and then surgical resection of the uterine mass with palliative radiotherapy of the right elbow. The postoperative imaging showed new metastasis, and the patient was scheduled to start on immunotherapy. Considering the highly invasive nature of uterine carcinosarcomas, timely detection of this cancer using characteristic imaging and pathology findings is of extreme importance to improve the patient's survival.

A Concise Review and Required Precautions for COVID-19 Outbreak in Diagnostic and Interventional Radiology.

A global outbreak of a novel coronavirus (COVID-19) pneumonia began in December 2019 in Wuhan, China. The World Health Organization (WHO) announced a pandemic on March 11, 2020. The rapid rise in the case numbers and mortality led to the saturation of hospitals in many countries. COVID-19 patients usually present with fever, fatigue, dry cough, and dyspnea. Given the shortage of diagnostic kits in many countries and very high sensitivity of computed tomography (CT) for diagnosis of COVID-19 in clinically suspicious patients, the chest CT has been implemented among the primary initial methods of diagnosis before the confirmatory laboratory tests. This puts radiologists and radiology staff on the front line of this alarming pandemic. This report summarizes chest CT findings of COVID-19 patients to facilitate diagnosis and reviews a list of necessary precautions and safety measures for diagnostic and interventional radiology personnel. These precautionary plans are extremely important to avoid contamination of the health-care providers, as well as cross-contamination between patients.

Adult-onset ganglioneuroblastoma of the posterior mediastinum with osseous metastasis.

Ganglioneuroblastomas are a member of the neuroblastic family of tumors most commonly seen in children but they may also occur in adults. Ganglioneuroblastomas have metastatic potential and, like other neuroblastic tumors, osseous metastasis is possible. Imaging features of ganglioneuroblastomas tend to be variable. We describe a case of an adult female who developed a ganglioneuroblastoma of the posterior mediastinum that metastasized to the thoracolumbar spine, highlighting rarely documented osseous metastasis.

SMARCA4-deficient uterine sarcoma: A case report and a concise review.

BACKGROUND: SMARCA4-deficient uterine sarcoma (SDUS) is a newly discovered undifferentiated uterine mesenchymal malignancy which has loss of expression of SMARCA4. CASE: A 46-year-old woman presented with heavy irregular vaginal bleeding over the previous 5 months. Computed tomography and magnetic resonance imaging showed a large pelvic mass centered within the uterus, suspicious of malignancy with regional metastatic lymphadenopathy. Biopsy confirmed SDUS and patient underwent chemotherapy. Her symptoms improved 3 months after treatment. CONCLUSION: An extremely rare case of this newly described entity is reported. Recognizing the characteristic imaging and pathology findings of SDUS is essential for an accurate diagnosis, which may affect patient survival.

Adrenal angiosarcoma with metastasis: Imaging and histopathology of a rare adrenal cancer.

Adrenal angiosarcoma is an extremely rare malignancy with few reported cases in the literature. Patients may be asymptomatic or have nonspecific complaints at presentation. There are no pathognomonic imaging findings, while histopathology can be confounding due to overlap with other disease processes. We present a case of a 38-year-old woman with a long history of cocaine abuse who had metastatic adrenal angiosarcoma at the time of presentation. The adrenal tumor was an incidental finding on imaging. CT demonstrated a heterogeneous mass in the right adrenal gland with central calcification, and MRI identified central necrosis in the mass. Histopathology demonstrated sheets of epithelioid cells, dilated anastomotic vascular spaces, and abundant necrosis, and immunohistochemistry was positive for various vascular markers. The findings were consistent with adrenal angiosarcoma. The patient underwent adrenalectomy and is now receiving adjuvant chemotherapy. Due to the aggressive nature of adrenal angiosarcoma, timely diagnosis and treatment is critical. This case adds to the sparse literature surrounding this disease by highlighting crucial imaging and histopathologic findings that will aid in more efficient diagnosis. Although rare, the disease should be considered in the context of suspicious adrenal lesions. In the future, structured review of all reported cases of adrenal angiosarcoma can help inform diagnosis and therapy for this rare disease.

Paraspinal Fat Stranding as an Unexpected Finding on Body Computed Tomography: A Key to Early Detection of Spinal Osteomyelitis.

OBJECTIVE: At present, early detection of spinal osteomyelitis is a challenge. Patients may present with non-specific symptoms and diagnostic imaging studies may be obtained for seemingly unrelated complaints. Paraspinal fat stranding on body computed tomography (CT) as a sign of osteomyelitis is easily overlooked and has not been reported in the literature to our knowledge. The purpose of this study is to review findings on body CT that points to unsuspected spinal osteomyelitis. MATERIAL AND METHODS: A retrospective review of patients with spinal osteomyelitis who also had concomitant chest, abdominal, or pelvic CT scans between August 2013 and February 2017 yielded 10 patients who had confirmed osteomyelitis (ages between 51 and 75, mean age 64.8). Images and medical records were reviewed. RESULTS: The age of the patients ranged from 51 to 75 years (median value, 64). All patients had multiple underlying medical illnesses, and half of them had a known preceding infection such as sepsis or urinary tract infection. At presentation, three patients had a fever and two patients had neurologic deficits. Seven out of eight patients had elevated C-reactive protein and erythrocyte sedimentation rate, five patients had leukocytosis, and four patients had positive blood cultures. Paravertebral fat stranding and endplate erosions were observed in 9 and 6 cases, respectively, on initial body CT for unrelated indications, and subsequent magnetic resonance imaging confirmed osteomyelitis discitis. CONCLUSION: Clinically significant, but initially unsuspected, spinal pathology such as osteomyelitis may present on body CT scans. Earlier diagnosis of spinal osteomyelitis can be made by performing a focused evaluation of the paraspinal soft tissues and including osteomyelitis in the differential diagnosis, particularly in high-risk patients.

Spectrally tunable infrared plasmonic F,Sn:In2O3 nanocrystal cubes.

A synthetic challenge in faceted metal oxide nanocrystals (NCs) is realizing tunable localized surface plasmon resonance (LSPR) near-field response in the infrared (IR). Cube-shaped nanoparticles of noble metals exhibit LSPR spectral tunability limited to visible spectral range. Here, we describe the colloidal synthesis of fluorine, tin codoped indium oxide (F,Sn:In2O3) NC cubes with tunable IR range LSPR for around 10 nm particle sizes. Free carrier concentration is tuned through controlled Sn dopant incorporation, where Sn is an aliovalent n-type dopant in the In2O3 lattice. F shapes the NC morphology into cubes by functioning as a surfactant on the {100} crystallographic facets. Cube shaped F,Sn:In2O3 NCs exhibit narrow, shape-dependent multimodal LSPR due to corner, edge, and face centered modes. Monolayer NC arrays are fabricated through a liquid-air interface assembly, further demonstrating tunable LSPR response as NC film nanocavities that can heighten near-field enhancement (NFE). The tunable F,Sn:In2O3 NC near-field is coupled with PbS quantum dots, via the Purcell effect. The detuning frequency between the nanocavity and exciton is varied, resulting in IR near-field dependent enhanced exciton lifetime decay. LSPR near-field tunability is directly visualized through IR range scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS). STEM-EELS mapping of the spatially confined near-field in the F,Sn:In2O3 NC array interparticle gap demonstrates elevated NFE tunability in the arrays.

Histologically benign metastasizing tenosynovial giant cell tumor mimicking metastatic malignancy: A case report and review of literature.

Diffuse-type tenosynovial giant cell tumor (D-TGCT), otherwise known as pigmented villonodular synovitis, is a locally aggressive tumor which can show multiple recurrences but is rarely associated with metastasis. A handful of studies have elucidated the imaging features and clinical course in metastatic D-TGCT with malignant transformation on histology. However, only 5 cases of metastatic D-TGCT with benign histological features have been reported in the literature, with the clinical course and prognosis reported in only 1 case. Therefore, relatively little is known about the implications of histologically benign metastasis on the role of imaging, management, and clinical outcomes. We report a case of a 51-year-old female with recurrent D-TGCT localized to the knee that metastasized to the lymph nodes and soft tissue 3 years after above-the-knee amputation and 16 years after initial diagnosis of localized D-TGCT, despite benign histologic features on lymph node excision. This case highlights the necessity of timely MRI imaging to prevent delayed diagnosis, the role of histological findings on treatment response, and clinical outcomes associated with metastasized D-TGCT.

Intraductal papillary mucinous neoplasm complicated by a gastropancreatic fistula.

One of the rare complications of low-grade pancreatic neoplasms is fistulization into nearby structures. This often does not present clinically, but is incidentally identified in patients who have been imaged serially to monitor the progression of the disease. In this report, we present an uncommon complication of an intraductal papillary mucinous neoplasm, which developed a spontaneous gastropancreatic fistula in a patient who was conservatively managed. The clinical course, imaging features, and management of this case are discussed.

Constructing and Pilot Testing a Novel Prostate Magnetic Resonance Imaging/Ultrasound Fusion Biopsy Phantom.

OBJECTIVE: To describe the design and build of a novel phantom for magnetic resonance imaging (MRI)/ultrasound (US) fusion biopsy and present pilot testing results from a multicenter urology resident training session. METHODS: We cast our phantom from polyvinylchloride-plastisol that features 10 mm and 5 mm blue clay tumors, a urethral lumen, and an echogenic capsule. T2-weighted images were acquired with a 3T MR750 scanner (GE Healthcare, Boston, MA). Fusion testing was performed on the bkFusion system (BK ultrasound, Peabody, MA) with MIM Symphony software (MIM, Cleveland, OH) and an 18-gauge Bard Monopty disposable gun (Bard, Murray Hill, NJ). Twenty residents from 6 urology programs in Chicago performed proctored user testing. RESULTS: The per phantom material cost was $12. The phantom was compatible with all necessary equipment to create a MRI/US fusion data set. MRI and US imaging characteristics were excellent with hypointense lesions. Image fusion was achieved through both end and side fire ultrasound probes. The phantom allowed for biopsies to be performed, and target lesion hits were confirmed by visual inspection of core samples. 38% (8/21) of urology resident pilot testing participants had previously performed a fusion biopsy. The mean postsession survey scores were (1-10 [best]): realism 9.0, usefulness 9.4, ease of use 9.1, ease of orientation 8.9, and overall experience 9.3. CONCLUSION: This simple and inexpensive phantom allows for training and accuracy testing of MRI/US fusion biopsy hardware and software platforms.

Pancreaticopleural Fistula: A Review of Imaging Diagnosis and Early Endoscopic Intervention.

A 49-year-old male with history of chronic alcohol-induced pancreatitis presented with one month of worsening left pleuritic chest pain and shortness of breath. Chest radiograph demonstrated bilateral pleural effusions. Thoracentesis revealed increased amylase in the pleural fluid. Computed tomography (CT) and magnetic resonance cholangiopancreatography (MRCP) showed a fistula tract between the left pleural cavity and pancreas which was confirmed on endoscopic retrograde cholangiopancreatography (ERCP). Patient was treated with placement of a pancreatic stent with complete resolution of the fistula tract approximately in 9 weeks. A systematic literature search was performed on reported cases with pancreaticopleural fistula (PPF) who underwent early therapeutic endoscopy within the last 10 years. Imaging modalities, particularly CT and MRCP, play essential role in prompt preprocedural diagnosis of PPF. Early therapeutic ERCP is an effective and relatively safe treatment option for PPF, so invasive surgery may be avoided.

Review of breast augmentation and reconstruction for the radiologist with emphasis on MRI.

It is imperative to continue screening for breast cancer and/or detect tumor recurrence in patients after they have undergone breast augmentation or reconstruction. As there is an increasing role for both screening and diagnostic imaging of the post-operative breast, it is important for the radiologist to be familiar with the commonly performed surgical techniques in breast augmentation and reconstruction. Imaging of the augmented and reconstructed breast, as well as complications, will be reviewed with a focus on Magnetic Resonance Imaging (MRI).