T1 signal intensity ratio of the pancreas as an imaging biomarker for the staging of chronic pancreatitis.

PURPOSE: Our purpose was to validate the T1 SIR (T1 score) as an imaging biomarker for the staging of CP in a large, multi-institutional, prospective study. METHODS: The prospective study population included 820 participants enrolled in the PROCEED study from nine clinical centers between June 2017 and December 2021. A radiologist at each institution used a standardized method to measure the T1 signal intensity of the pancreas and the reference organs (spleen, paraspinal muscle, liver), which was used to derive respective T1 scores. Participants were stratified according to the seven mechanistic stages of chronic pancreatitis (MSCP 0-6) based on their clinical history, MRCP, and CT findings. RESULTS: The mean pancreas-to-spleen T1 score was 1.30 in participants with chronic abdominal pain, 1.22 in those with acute or recurrent acute pancreatitis, and 1.03 in definite CP. After adjusting for covariates, we observed a linear, progressive decline in the pancreas-to-spleen T1 score with increasing MSCP from 0 to 6. The mean pancreas-to-spleen T1 scores were 1.34 (MSCP 0), 1.27 (MSCP 1), 1.21 (MSCP 2), 1.16 (MSCP 3), 1.18 (MSCP 4), 1.12 (MSCP 5), and 1.05 (MSCP 6) (p < 0.0001). The pancreas-to-liver and pancreas-to-muscle T1 scores showed less linear trends and wider confidence intervals. CONCLUSION: The T1 score calculated by SIR of the pancreas-to-spleen shows a negative linear correlation with the progression of chronic pancreatitis. It holds promise as a practical imaging biomarker in evaluating disease severity in clinical research and practice.

Inter-observer variability of radiologists for Cambridge classification of chronic pancreatitis using CT and MRCP: results from a large multi-center study.

PURPOSE: Determine inter-observer variability among radiologists in assigning Cambridge Classification (CC) of chronic pancreatitis (CP) based on magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP) and contrast-enhanced CT (CECT). METHODS: Among 422 eligible subjects enrolled into the PROCEED study between 6/2017 and 8/2018, 39 were selected randomly for this study (chronic abdominal pain (n = 8; CC of 0), suspected CP (n = 22; CC of 0, 1 or 2) or definite CP (n = 9; CC of 3 or 4). Each imaging was scored by the local radiologist (LRs) and three of five central radiologists (CRs) at other consortium sites. The CRs were blinded to clinical data and site information of the participants. We compared the CC score assigned by the LR with the consensus CC score assigned by the CRs. The weighted kappa statistic (K) was used to estimate the inter-observer agreement. RESULTS: For the majority of subjects (34/39), the group assignment by LR agreed with the consensus composite CT/MRCP score by the CRs (concordance ranging from 75 to 89% depending on cohort group). There was moderate agreement (63% and 67% agreed, respectively) between CRs and LRs in both the CT score (weighted Kappa [95% CI] = 0.56 [0.34, 0.78]; p-value = 0.57) and the MR score (weighted Kappa [95% CI] = 0.68 [0.49, 0.86]; p-value = 0.72). The composite CT/MR score showed moderate agreement (weighted Kappa [95% CI] = 0.62 [0.43, 0.81]; p-value = 0.80). CONCLUSION: There is a high degree of concordance among radiologists for assignment of CC using MRI and CT.

Urethrographic Evaluation of Anatomic Findings and Complications after Perineal Masculinization and Phalloplasty in Transgender Patients.

Transgender patients seeking gender-affirming surgery are a growing population with unique health care needs. The radiologist must understand the challenges these patients face to facilitate a positive patient-physician interaction during the series of postoperative fluoroscopic evaluations. The authors present a standard two-stage surgical approach and common postoperative fluoroscopic findings after perineal masculinization and phalloplasty procedures. Perineal masculinization including urethral lengthening is performed first, followed by skin-flap-based phalloplasty. Patients undergo voiding cystourethrography (VCUG) after intravesical administration of contrast media by way of an indwelling suprapubic catheter after each stage. Retrograde urethrography plays a complementary role to supplement the limitations of VCUG after the second stage. The article reviews the expected postoperative anatomy and explains standardized terminology developed at the authors' institution. Imaging features of common and rare complications are discussed, including contained leak, stenosis, occlusion, and fistula. The successful postoperative imaging study in a transmasculine patient relies on open communication among the interdisciplinary team of specialized surgeons, radiologists, and medical providers, as well as special modifications to existing imaging techniques. ©RSNA, 2020.

The Clinical Impact of Resident-attending Discrepancies in On-call Radiology Reporting: A Retrospective Assessment.

RATIONALE AND OBJECTIVES: The purpose of this study is to quantify the clinical impact of resident-attending discrepancies at a tertiary referral academic radiology residency program by assessing rates of intervention, discrepancy confirmation, recall rate, and management change rate; furthermore, a discrepancy categorization system will be assessed. MATERIALS AND METHODS: Retrospective review of the records was performed for n = 1482 discrepancies that occurred in the 17-month study period to assess the clinical impact of discrepancies. Discrepancies were grouped according to a previously published classification system. Management changes were recorded and grouped by severity. The recall rate was estimated for discharged patients. Any confirmatory testing was reviewed to evaluate the accuracy of the discrepant report. Categorical variables were compared to the chi-square test. RESULTS: The 1482 discrepancies led to management change in 661 cases (44.6%). The most common management change was follow-up imaging. Procedural interventions including surgery occurred in 50 cases (3.3%). The recall rate was 2.6%. Management changes were more severe with computed tomography examinations, inpatients, and when the discrepancy was in the chest and abdomen subspecialty. Also, management changes correlated with the discrepancy category assigned by the attending at the time of review. CONCLUSIONS: Resident-attending discrepancies do cause management changes in 44.6% of discrepancies (0.62% overall); the most frequent change is follow-up imaging. The discrepancy categorization assigned by the attending correlated with the severity of management change.

Ki-67 predicts disease recurrence and poor prognosis in pancreatic neuroendocrine neoplasms.

BACKGROUND: Pancreatic neuroendocrine neoplasms are rare malignancies for which the ideal staging method remains controversial. Ki-67 is a cell proliferation marker that has been shown to have some utility in predicting prognosis in neuroendocrine neoplasms. We sought to test the predictive ability of Ki-67 staining for disease recurrence and overall survival (OS) in pancreatic neuroendocrine neoplasms. METHODS: The medical records of patients who underwent pancreatic resection for pancreatic neuroendocrine neoplasms at a tertiary referral hospital from 1994 to 2009 were reviewed. The pathologic specimens of all were stained for Ki-67 and recorded as percentage of cells staining positive per high-powered field. The 10-year disease-free and OSs were analyzed. RESULTS: We identified 140 patients. Gender and age were not associated with increased risk of disease recurrence. Patients with tumors >4 cm or with Ki-67 staining >9% were more likely to have disease recurrence (P = .0454 and .047) and have decreased OS (P < .0001 and .0007). CONCLUSION: Increasing tumor size and increasing Ki-67 staining both correlate with increased risk of disease recurrence and decreased OS. Designing a staging system that incorporates both of these clinical variables will enable better identification of patients at risk for recurrent pancreatic neuroendocrine neoplasms.

Absence of long-wavelength photic potentiation of murine intrinsically photosensitive retinal ganglion cell firing in vitro.

Melanopsin is an opsin-family photopigment required for photosensitivity of the intrinsically photosensitive retinal ganglion cells (ipRGCs), which subserve photic entrainment of circadian rhythms in mammals. The melanopsin photocycle is presently unknown but is independent of the enzymatic photocycle employed by rhodopsin and cone opsins. Recent experiments have demonstrated that red-light exposure potentiates circadian phase-shifting responses to blue-light stimuli, consistent with the hypothesis that melanopsin functions as a bistable photopigment. To further test this hypothesis, we analyzed ipRGC firing activity in response to 480-nm blue light with or without intervening long-wavelength 620-nm red-light stimulation, using in vitro multielectrode array recording of postnatal day 8 to 10 murine retina. Cell-firing responses to 480-nm light were highly reproducible. No significant potentiating or bleaching effect of intervening subthreshold 620-nm light on ipRGC firing to 480-nm light could be discerned. Further physiologic and biochemical analysis of the ipRGC photoreception is required to reconcile the presence of long-wavelength potentiation at the level of the SCN with its absence in light-induced ipRGC firing.