Multiparametric MRI Scoring System of the Pancreas for the Diagnosis of Chronic Pancreatitis.

BACKGROUND: Ductal features alone may not offer high diagnostic sensitivity or most accurate disease severity of chronic pancreatitis (CP). PURPOSE: Diagnose CP based on multiparametric MRI and MRCP features. STUDY TYPE: Prospective. POPULATION: Between February 2019 and May 2021, 46 control (23 males, 49.3 ± 14.1 years), 45 suspected (20 males, 48.7 ± 12.5 years), and 46 definite (20 males, 53.7 ± 14.6 years) CP patients were enrolled at seven hospitals enrolled in the MINIMAP study. CP classification was based on imaging findings and clinical presentation. FIELD STRENGTH AND SEQUENCES: 1.5 T. T1-weighted (T1W) spoiled gradient echo, T1 map with variable flip angle, dual-echo Dixon, secretin-enhanced MRCP before and after secretin infusion. ASSESSMENT: Dual-echo fat fraction (FF), T1 relaxation time, extracellular volume (ECV), T1 signal intensity ratio of the pancreas to the spleen (T1 score), arterial-to-venous enhancement ratio (AVR), pancreatic tail diameter (PTD), pancreas volume, late gadolinium enhancement, pancreatic ductal elasticity (PDE), and duodenal filling grade of secretin-enhanced MRCP were measured. STATISTICAL TESTS: Logistic regression analysis generated CP-MRI and secretin-enhanced CP-SMRI scores. Receiver operating characteristics analysis was used to differentiate definite CP from control. Interobserver agreement was assessed using Lin's concordance correlation coefficient. RESULTS: Compared to control, definite CP cohort showed significantly higher dual-echo FF (7% vs. 11%), lower AVR (1.35 vs. 0.85), smaller PTD (2.5 cm vs. 1.95 cm), higher ECV (28% vs. 38%), and higher incidence of PDE loss (6.5% vs. 50%). With the cut-off of >2.5 CP-MRI score (dual-echo FF, AVR, and PTD) and CP-SMRI score (dual-echo FF, AVR, PTD, and PDE) had cross-validated area under the curves of 0.84 (sensitivity 87%, specificity 68%) and 0.86 (sensitivity 89%, specificity 67%), respectively. Interobserver agreement for both CP-MRI and CP-SMRI scores was 0.74. CONCLUSION: The CP-MRI and CP-SMRI scores yielded acceptable performance and interobserver agreement for the diagnosis of CP. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.

Role of genetic introgression in introducing mutant alleles in Bos indicus cattle and prevalence of lethal genetic disorders in Bos taurus × Bos indicus and Bos indicus cattle in India.

Fertility is an important trait associated with reproductive performance and animal welfare concern. Lethal alleles affect fertility through early embryonic death, abortions, and stillbirth depending on the genetic expression of the allele. Holstein Friesian and Jersey are two major Bos taurus breeds used widely for increasing milk yield along with purebreds of Bos indicus breeds like Gir, Kankrej, Sahiwal, and Tharparkar. In the present study, prevalence of lethal mutants in crossbred Holstein Friesian (CBHF, n = 2435), crossbred Jersey (CBJY, n = 2874), Gir (n = 3288), Kankrej (n = 593), Sahiwal (n = 965), and Tharparkar (n = 18) were studied. Heterozygous carrier animals were identified for bovine leukocyte adhesion deficiency (BLAD), Citrullinemia, complex vertebral malformation (CVM), Brachyspina, Holstein Haplotype 1 (HH1), Holstein Haplotype 3 (HH3),Holstein Haplotype 4 (HH4) and Jersey Haplotype 1 (JH1). Breed purity analysis confirmed inheritance of Bos taurus genes contributing to the presence of lethal mutant alleles like BLAD, Citrullinemia, HH1, and JH1 in apparently phenotypic Bos indicus animals. Screening and elimination of heterozygous carrier bulls/cows is essential to control fertility loss associated with lethal alleles.

Contrast-Enhanced Ultrasound Versus Doppler Ultrasound for Detection of Early Vascular Complications of Pancreas Grafts.

OBJECTIVE. The purpose of this study is to compare conventional duplex ultrasound and contrast-enhanced ultrasound (CEUS) for identifying vascular abnormalities in pancreas allografts in the immediate posttransplant setting. Identification of pancreas allografts at risk of failure may impact patient care because early intervention for vascular insufficiency can lead to graft salvage. MATERIALS AND METHODS. Two radiologists who were blinded to patient outcomes performed a retrospective analysis of the postoperative Doppler ultrasound and CEUS images of 34 pancreas grafts from transplants performed between 2017 and 2019. A total of 28 patients who did not require surgical reexploration were considered the control group. Six patients had surgically proven arterial or venous abnormalities on surgical reexploration. Each radiologist scored grafts as having normal or abnormal vascularity on the basis of image sets obtained using Doppler ultrasound only and CEUS only. Comparisons of both the diagnostic performance of each modality and interobserver agreement were performed. RESULTS. Both readers showed that CEUS had increased sensitivity for detecting vascular abnormalities (83.3% for both readers) compared with Doppler ultrasound (66.7% and 50.0%). For both readers, the specificity of CEUS was similar to that of Doppler imaging (81.6% and 78.9% for reader 1 and reader 2 versus 76.3% and 84.2% for reader 1 and reader 2). For both readers, the negative predictive value of CEUS was higher than that of Doppler ultrasound (96.9% and 96.8% for reader 1 and reader 2 versus 93.5% and 91.4% for reader 1 and reader 2). Interobserver agreement was higher for CEUS than for Doppler ultrasound (κ = 0.54 vs κ = 0.28). CONCLUSION. CEUS may provide radiologists and surgeons with a means of timely and effective evaluation of pancreas graft perfusion after surgery, and it may help identify grafts that could benefit from surgical salvage.

Acinarization (parenchymal blush) observed during secretin-enhanced MRCP: clinical implications.

OBJECTIVE: T2 hyperintensity of pancreatic acini during secretin-enhanced MRCP is called "acinarization." We sought to determine the clinical significance of this finding. MATERIALS AND METHODS: Patients were selected if the radiology report included the phrases "acin*" (where * represented a wild card search) or "blush" using the institution's customized lexicon-search software. Sixty-seven consecutive patients without acinarization on secretin-enhanced MRCP who also underwent ERCP were enrolled as the control group. The intensity of acinarization was classified into three groups: grade 0, no visible acinarization; grade 1, barely visible parenchymal hyperintensity; or grade 2, easily visible parenchymal hyperintensity. ERCP findings of ductal abnormalities and basal pancreatic sphincter manometry were recorded. RESULTS: There were higher frequencies of divisum (p = 0.001) and of a clinical history of recurrent acute pancreatitis (p < 0.001) and higher basal pancreatic sphincter of Oddi manometric pressure measurements (p = 0.008) in the acinarization group. There was no difference in the frequency of ERCP-defined chronic pancreatitis (p = 0.10) between the groups. In patients with acinarization, a higher mean sphincter pressure was seen in patients with more intense acinarization than in those with faint acinarization, but this difference was not significant (p = 0.22). Ampullary tumors were found in four patients with acinarization. CONCLUSION: Acinarization probably occurs in patients with a propensity for increased pancreatic ductal pressure (i.e., patients with divisum, elevated basal pancreatic sphincter pressure, ampullary tumor) and adequate exocrine function (absence of severe chronic pancreatitis).

Patellar clunk syndrome in a current high flexion total knee design.

This retrospective study of 208 (204 patients) total knee arthroplasties evaluated the incidence of patellar clunk syndrome for two high-flex posterior stabilized knee prostheses; a high-flex fixed bearing prosthesis and a high-flex mobile bearing prosthesis. Patients were followed for up to two years and were evaluated for patellar clunk and component position. Knees receiving the mobile bearing had a significantly higher (p < 0.001) incidence of patellar clunk (15%) than knees receiving the fixed bearing (0%). There was a significantly higher incidence of patellar clunk in males (34.1%; p < 0.01) compared to females (8.6%). Fibrous nodules were treated surgically in 11 of the knees with patellar clunk. The design of this particular mobile bearing knee seems to contribute to patellar clunk syndrome.

Flaps, slings, and other things: CT after reconstructive surgery--expected changes and detection of complications.

OBJECTIVE: This article will discuss the typical CT appearance of myocutaneous surgically placed flaps as well as some frequently encountered complications of this surgery. We will discuss the appearance of relatively new, but increasingly encountered, nonnative materials used in reconstructive surgery, such as spacers, bulking agents, hemostatic agents, and other reconstructive materials. CONCLUSION: Oncologic surgery often requires reconstruction using myocutaneous flaps. Therefore, an understanding of the type of reconstruction performed is important for the accuracy of postoperative radiologic interpretation to recognize presence of a flap to avoid misdiagnosis of tumor recurrence.

Peritoneal and retroperitoneal anatomy and its relevance for cross-sectional imaging.

It is difficult to identify normal peritoneal folds and ligaments at imaging. However, infectious, inflammatory, neoplastic, and traumatic processes frequently involve the peritoneal cavity and its reflections; thus, it is important to identify the affected peritoneal ligaments and spaces. Knowledge of these structures is important for accurate reporting and helps elucidate the sites of involvement to the surgeon. The potential peritoneal spaces; the peritoneal reflections that form the peritoneal ligaments, mesenteries, and omenta; and the natural flow of peritoneal fluid determine the route of spread of intraperitoneal fluid and disease processes within the abdominal cavity. The peritoneal ligaments, mesenteries, and omenta also serve as boundaries for disease processes and as conduits for the spread of disease.

Histopathologic correlation of pancreatic fibrosis with pancreatic magnetic resonance imaging quantitative metrics and Cambridge classification.

PURPOSE: To determine the correlation of the T1-weighted signal intensity ratio (T1 SIR, or T1 Score) and arterial-to-delayed venous enhancement ratio (ADV ratio) of the pancreas with pancreatic fibrosis on histopathology. METHODS: Sixty consecutive adult CP patients who had an MRI/MRCP study prior to pancreatic surgery were analyzed. Three blinded observers measured T1 SIR of pancreas to spleen (T1 SIR p/s), pancreas-to-paraspinal muscle (T1 SIR p/m), ADV ratio, and Cambridge grade. Histopathologic grades were given by a gastrointestinal pathologist using Ammann's fibrosis score. Statistical analysis included Spearman's correlation coefficient of the T1 SIR, ADV ratio, Cambridge grade with the fibrosis score, and weighted kappa for interobserver agreement. RESULTS: The study population included 31 female and 29 male patients, with an average age of 52.1 (26-78 years). Correlations between fibrosis score and T1 SIR p/s, T1 SIR p/m, and ADV ratio were ρ = - 0.54 (p = 0.0001), ρ = - 0.19 (p = 0.19), and ρ = - 0.39 (p = 0.003), respectively. The correlation of Cambridge grade with fibrosis score was ρ = 0.26 (p = 0.07). There was substantial interobserver agreement (weighted kappa) for T1 SIR p/s (0.78), T1 SIR p/m (0.71), and ADV ratio (0.64). T1 SIR p/s of ≤ 1.20 provided a sensitivity of 74% and specificity of 50% (AUC: 0.74), while ADV ratio of ≤ 1.10 provided a sensitivity of 75% and specificity of 55% (AUC: 0.68) to detect a fibrosis score of ≥ 6. CONCLUSION: There is a moderate negative correlation between the T1 Score (SIR p/s) and ADV ratio with pancreatic fibrosis and a substantial interobserver agreement. These parenchymal metrics show a higher correlation than the Cambridge grade.

Characterization of adrenal masses with diffusion-weighted imaging.

OBJECTIVE: The purpose of this article is to assess the role of diffusion-weighted MRI in characterizing adrenal masses. MATERIALS AND METHODS: A retrospective review of the MRI database from August 2007 to July 2009 was performed. The MRI examinations of 48 patients, with 49 lesions, were reviewed independently and blindly by two experienced abdominal radiologists who measured the signal intensities on in-phase and opposed-phase T1-weighted imaging and apparent diffusion coefficient (ADC). ADC measurements and quantitative parameters of chemical shift imaging (signal intensity index and adrenal-to-spleen ratio) were assessed separately and in combination. Lesions with indeterminate signal intensity index (< 16.5%) were considered benign if ADC was greater than or equal to 1.0 × 10(-3) mm(2)/s and malignant if ADC was less than 1.0 × 10(-3) mm(2)/s. Stepwise logistic regression analysis and receiver operating characteristic curves analysis were performed. RESULTS: There were 12 malignant and 37 benign lesions. On multivariate analysis, the only significant predictors of lesion status were signal intensity index from reviewer 2 (p = 0.05) and lesion size (p = 0.04); ADC values were not found to be useful. On receiver operating characteristic curve analysis, there was no significant difference in area under the curve for ADC, signal intensity index, adrenal-to-spleen ratio, or the combined signal intensity index and ADC assessment. For lesions that were indeterminate according to signal intensity index, ADC values greater than 1.50 × 10(-3) mm(2)/s were found only in benign lesions, and nine of 11 lesions with ADC less than 1.0 × 10(-3) mm(2)/s were malignant. CONCLUSION: In general, ADC values are not useful in differentiating adrenal lesions. However, when ADC values are applied to lesions that are indeterminate on signal intensity index, they may help in differentiating a subset of benign and malignant lesions.

Single brain death examination is equivalent to dual brain death examinations.

BACKGROUND: Although the new Practice Parameters for brain death support a single examination, there is paucity of data comparing its impact to dual brain death (DBD) examinations. METHODS: We reviewed all brain deaths in our hospital over a 39-month period and compared the optional single brain death (SBD) exam requiring an apnea and a mandatory confirmatory blood flow test to the DBD for organ function at the time of death, rate of donation, and cost. RESULTS: Thirty-six patients had a SBD and 59 DBD exams, without any of them regaining neurological functioning. There was no difference in serum electrolytes (except for higher Na(+) and Cl(-) in the SBD group), blood urea nitrogen, creatinine, blood gases, incidence of diabetes insipidus, apnea completion, consent for donation, and organs recovered and transplanted. During the second BD exam, 35% of patients with DBD were on higher dose of vasopressors, but had lower systolic blood pressure (P = 0.046). For DBD patients, the mean interval between the two exams was 14.4 h, which contributed to a higher cost of $43,707.67 compared to SBD. There was a trend for increased consent rates (adjusted for age, race, and type of exam) when patients were declared by the neurointensivist service following a strict family approach protocol (P = 0.06). CONCLUSION: SBD exam is easier, faster to perform, with no brain function recovery and leads to similar donation rates, equivalent or better organ function status at the time of BD and lower cost than conventional DBD exams.

T1 mapping for the diagnosis of early chronic pancreatitis: correlation with Cambridge classification system.

OBJECTIVE: This study aims to determine if T1 relaxation time of the pancreas can detect parenchymal changes in early chronic pancreatitis (CP). METHODS: This study retrospectively analyzed 42 patients grouped as no CP (Cambridge 0; n = 21), equivocal (Cambridge 1; n = 12) or mild CP (Cambridge 2; n = 9) based on magnetic resonance cholangiopancreatography findings using the Cambridge classification as the reference standard. Unenhanced T1 maps were acquired using a three-dimensional dual flip-angle gradient-echo technique on the same 1.5 T scanner with the same imaging parameters. RESULTS: There was no significant difference between the T1 relaxation times of Cambridge 0 and 1 group (p = 0.58). There was a significant difference (p = 0.0003) in the mean T1 relaxation times of the pancreas between the combined Cambridge 0 and 1 (mean = 639 msec, 95% CI: 617, 660) and Cambridge 2 groups (mean = 726 msec, 95% CI: 692, 759). There was significant difference (p = 0.0009) in the mean T1 relaxation times of the pancreas between the Cambridge 0 (mean = 636 msec, 95% CI: 606, 666) and Cambridge 2 groups (mean = 726 msec, 95% CI: 692,759) as well as between Cambridge 1 (mean = 643 msec, 95% CI: 608, 679) and Cambridge 2 groups (mean = 726 msec, 95% CI: 692,759) (p = 0.0017). Bland-Altman analysis showed measurements of one reader to be marginally higher than the other by 15.7 msec (2.4%, p = 0.04). CONCLUSION: T1 mapping is a practical method capable of quantitatively reflecting morphologic changes even in the early stages of chronic pancreatitis, and demonstrates promise for future implementation in routine clinical imaging protocols. ADVANCES IN KNOWLEDGE: T1 mapping can distinguish subtle parenchymal changes seen in early stage CP, and demonstrates promise for implementation in routine imaging protocols for the diagnosis of CP.

Affective response to volitional input perturbations in obstacle avoidance and target tracking games.

We present the use of two game-like tasks, Catnip and Dinorun, to explore affective responses to volitional control perturbations. We analyze behavioral and physiological measures with the self-assessment manikin (SAM), pupillometry, and electroencephalography (EEG) responses to provide intratrial emotional state as well as inter-trial correlates with selfreported survey responses. We find that subject gameplay characteristics significantly correlate with valence and dominance scores for both games, and that perturbations to the games produce a measurable decrease in response scores for Dinorun. During perturbation events, pupillometry analysis reveals considerable SAM-agnostic dilation, with stronger responses in more rigid trialized event structures. Furthermore, analyses of neural activity from central and parietal regions demonstrate significant measurable evoked responses to perturbed events across the majority of subjects for both games. By introducing perturbations, this set of experiments and analyses inform and enable further studies of affective responses to the loss of volitional control during engaging, game-like tasks.

Pancreatic cystic neoplasms and post-inflammatory cysts: interobserver agreement and diagnostic performance of MRI with MRCP.

PURPOSE: We aimed to answer several clinically relevant questions; (1) the interobserver agreement, (2) diagnostic performance of MRI with MRCP for (a) branch duct intraductal papillary mucinous neoplasms (BD-IPMN), mucinous cystic neoplasms (MCN) and serous cystic neoplasms (SCN), (b) distinguishing mucinous (BD-IPMN and MCN) from non-mucinous cysts, and (c) distinguishing three pancreatic cystic neoplasms (PCN) from post-inflammatory cysts (PIC). METHODS: A retrospective analysis was performed at a tertiary referral center for pancreatic diseases on 71 patients including 44 PCNs and 27 PICs. All PCNs were confirmed by surgical pathology to be 17 BD-IPMNs, 13 MCNs, and 14 SCNs. Main duct and mixed type IPMNs were excluded. Two experienced abdominal radiologists blindly reviewed all the images. RESULTS: Sensitivity of two radiologists for BD-IPMN, MCN and SCN was 88-94%, 62-69% and 57-64%, specificity of 67-78%, 67-78% and 67-78%, and accuracy of 77-82%, 65-75% and 63-73%, respectively. There was 80% sensitivity, 63-73% specificity, 70-76% accuracy for distinguishing mucinous from non-mucinous neoplasms, and 73-75% sensitivity, 67-78% specificity, 70-76% accuracy for distinguishing all PCNs from PICs. There was moderate-to-substantial interobserver agreement (Cohen's kappa: 0.65). CONCLUSION: Two experienced abdominal radiologists had moderate-to-high sensitivity, specificity, and accuracy for BD-IPMN, MCN, and SCN. The interobserver agreement was moderate-to-substantial. MRI with MRCP can help workup of incidental pancreatic cysts by distinguishing PCNs from PICs, and premalignant mucinous neoplasms from cysts with no malignant potential.

Annular pancreas in adults.

OBJECTIVE: The purpose of this study was to review the CT, MRI, and ERCP findings of annular pancreas in adults. MATERIALS AND METHODS: A search of the radiology and ERCP databases at our institution for cases of annular pancreas in adults yielded the records of 42 patients who underwent 29 ERCP, 22 CT, and 13 MRI examinations. The CT and MR images were reviewed by two readers, and consensus agreement was reached regarding the shape of the pancreas, anatomic configuration of the ducts, and presence of disease. In addition, the degree of encirclement of the second part of the duodenum by the pancreatic head was evaluated in 24 patients with the CT or MRI finding of annular pancreas and in 30 control patients who were found not to have annular pancreas at ERCP. RESULTS: Nine of 24 (37.5%) cases of annular pancreas detected with CT or MRI did not have a radiologically complete ring of pancreatic tissue surrounding the second part of the duodenum. Three of the nine patients (33%) with radiologically incomplete annular pancreas and six of the 15 patients (40%) with complete annular pancreas had gastric outlet obstruction (p = 0.75). The presence of pancreatic tissue posterolateral to the second part of the duodenum had a high sensitivity (92%) and specificity (100%) for the presence of annular pancreas. The rates of pancreas divisum (37%) and chronic pancreatitis (48%) were high in this cohort. CONCLUSION: Annular pancreas can be diagnosed without the finding of a radiologically complete ring of pancreatic tissue. A crocodile jaw configuration of pancreatic tissue is suggestive of the presence of annular pancreas.

A Wearable Multi-Modal Bio-Sensing System Towards Real-World Applications.

Multi-modal bio-sensing has recently been used as effective research tools in affective computing, autism, clinical disorders, and virtual reality among other areas. However, none of the existing bio-sensing systems support multi-modality in a wearable manner outside well-controlled laboratory environments with research-grade measurements. This paper attempts to bridge this gap by developing a wearable multi-modal bio-sensing system capable of collecting, synchronizing, recording, and transmitting data from multiple bio-sensors: PPG, EEG, eye-gaze headset, body motion capture, GSR, etc., while also providing task modulation features including visual-stimulus tagging. This study describes the development and integration of various components of our system. We evaluate the developed sensors by comparing their measurements to those obtained by a standard research-grade bio-sensors. We first evaluate different sensor modalities of our headset, namely, earlobe-based PPG module with motion-noise canceling for ECG during heart-beat calculation. We also compare the steady-state visually evoked potentials measured by our shielded dry EEG sensors with the potentials obtained by commercially available dry EEG sensors. We also investigate the effect of head movements on the accuracy and precision of our wearable eye-gaze system. Furthermore, we carry out two practical tasks to demonstrate the applications of using multiple sensor modalities for exploring previously unanswerable questions in bio-sensing. Specifically, utilizing bio-sensing, we show which strategy works best for playing "Where is Waldo?" visual-search game, changes in EEG corresponding to true vs. false target fixations in this game, and predicting the loss/draw/win states through bio-sensing modalities while learning their limitations in a "Rock-Paper-Scissors" game.

Mental State Assessment and Validation Using Personalized Physiological Biometrics.

Mental state monitoring is a critical component of current and future human-machine interfaces, including semi-autonomous driving and flying, air traffic control, decision aids, training systems, and will soon be integrated into ubiquitous products like cell phones and laptops. Current mental state assessment approaches supply quantitative measures, but their only frame of reference is generic population-level ranges. What is needed are physiological biometrics that are validated in the context of task performance of individuals. Using curated intake experiments, we are able to generate personalized models of three key biometrics as useful indicators of mental state; namely, mental fatigue, stress, and attention. We demonstrate improvements to existing approaches through the introduction of new features. Furthermore, addressing the current limitations in assessing the efficacy of biometrics for individual subjects, we propose and employ a multi-level validation scheme for the biometric models by means of k-fold cross-validation for discrete classification and regression testing for continuous prediction. The paper not only provides a unified pipeline for extracting a comprehensive mental state evaluation from a parsimonious set of sensors (only EEG and ECG), but also demonstrates the use of validation techniques in the absence of empirical data. Furthermore, as an example of the application of these models to novel situations, we evaluate the significance of correlations of personalized biometrics to the dynamic fluctuations of accuracy and reaction time on an unrelated threat detection task using a permutation test. Our results provide a path toward integrating biometrics into augmented human-machine interfaces in a judicious way that can help to maximize task performance.

Abdominal compartment syndrome.

OBJECTIVE: The purpose of this article is to discuss the pathogenesis, clinical features, radiologic findings, and treatment of abdominal compartment syndrome, which is defined as an acute elevation of the intraabdominal pressure with organ dysfunction. CONCLUSION: Abdominal compartment syndrome is not well reported in the radiology literature. In this review, we discuss a range of CT signs such as elevated diaphragm, collapsed inferior vena cava, bowel wall thickening, bowel mucosal hyperenhancement, hemoperitoneum, and increasing abdominal girth, which, in combination, may allow the radiologist to raise the possibility of abdominal compartment syndrome.