Redefining the concept of residual renal function with kidney sodium MRI: a pilot study.

RATIONALE & OBJECTIVE: The concept of residual kidney function (RKF) is exclusively based upon urine volume and small solute clearance, making RKF challenging to assess in clinical practice. The aim of this study was to test the technical feasibility of obtaining useable 23Na-MRI kidney images in hemodialysis (HD) participants. STUDY DESIGN: We conducted an exploratory prospective study to quantify the cortico-medullary sodium gradient in healthy and HD participants. Participants fasted for eight hours prior to their study visit. Urine samples were collected to measure urinary osmolarity, before MRI. Proton and sodium pictures were merged; ROIs were delineated for the medulla and cortex when feasible. In cases where cortex could not be identified, we considered the cortico to medulla gradient (CMG) to be no longer present, resulting in a medulla-to-cortex ratio of 1. SETTING & PARTICIPANTS: 17 healthy volunteers and 21 HD participants. FINDINGS: Median (IQR) fasting medulla to cortex ratio was significantly higher 1.56 [1.5-1.61] in healthy volunteers compared to HD patients 1.22 [1.13-1.3], p < 0.0001. Medulla to cortex ratio and median urinary osmolarity were correlated (r = 0.87, p < 0.0001) in the whole population. We found a significant association between HD vintage and medulla to cortex ratio whereas we did not find any association with urine volume. Sodium signal intensity distribution within healthy kidney describes two different peaks- relating to well defined cortex and medulla; whereas HD participants displays only a single peak indicative of the markedly lower sodium concentration. LIMITATIONS: This study is only an exploratory study with a modest number of patients. CONCLUSIONS: the application of kidney sodium MRI to the study of RKF in patients receiving maintenance HD is practical and provides a previously unavailable ability to interrogate the function of remnant tubular function.

Thoracic Imaging in Pediatric Trauma: Are CTs Necessary?

OBJECTIVES: Imaging algorithms for assessment of thoracic trauma in pediatric patients remain controversial, attempting to balance radiation dose and its associated risk with the need for thorough assessment of patients' injuries. This study reviewed the value of chest radiography in detecting traumatic injuries, and the impact that computed tomography (CT) had on clinical management. METHODS: A retrospective review of pediatric trauma patients undergoing chest radiography and thoracic CT over a 2-year period at a level 1 trauma center was performed. The incidence of various traumatic injuries was documented, with measures of sensitivity and specificity on radiography. Clinical notes were reviewed to identify any changes in care based on CT findings. RESULTS: Eighty-one pediatric trauma patients underwent thoracic CT over a 2-year period, with 60 patients meeting the inclusion criteria. Radiographs identified 47 traumatic injuries out of 117 seen on the subsequent CT examinations for a sensitivity of 41% and specificity of 91%. Radiographs were most sensitive in detecting osseous injuries with a sensitivity of 54%. Additional CT findings changed management in 2 of 60 cases, or 3.3% of the time. CONCLUSIONS: Use of thoracic CT in pediatric trauma patients identifies a significantly greater number of injuries compared with than radiography but significantly increases radiation dose while changing management in only a very small proportion of cases. Despite the relatively small sample size, the findings reflect 2 years of experience at a level 1 trauma center, and this study suggests that it may be reasonable to decrease the frequency of cross-sectional imaging.

Recommendations for the Management of Incidental Musculoskeletal Findings on MRI and CT.

The Canadian Association of Radiologists (CAR) Incidental Findings Working Group consists of both academic subspeciality and general radiologists tasked with either adapting American College of Radiology (ACR) guidelines to meet the needs of Canadian radiologists or authoring new guidelines where appropriate. In this case, entirely new guidelines to deal with incidental musculoskeletal findings that may be encountered on thoracoabdominal computed tomography or magnetic resonance imaging were drafted, focussing on which findings should prompt recommendations for further workup. These recommendations discuss how to deal with incidental marrow changes, focal bone lesions, abnormalities of the pubic symphysis and sacroiliac joints, fatty soft tissue masses, manifestations of renal osteodystrophy and finally discuss opportunistic osteoporosis evaluation.

Recommendations for the Management of Incidental Pancreatic Findings in Adults by the Canadian Association of Radiologists Incidental Findings Working Group.

The Canadian Association of Radiologists Incidental Findings Working Group consists of both academic subspecialty and general radiologists and is tasked with adapting and expanding upon the American College of Radiology incidental findings white papers to more closely apply to Canadian practice patterns, particularly more comprehensively dealing with the role of ultrasound and pursuing more cost-effective approaches to the workup of incidental findings without compromising patient care. Presented here are the 2021 Canadian guidelines for the management of pancreatic incidental findings. Topics covered include anatomic variants, fatty atrophy, pancreatic calcifications, ductal ectasia, and management of incidental pancreatic cysts.

Point-of-care ultrasonography for the diagnosis of testicular torsion: a practical resident curriculum.

Background: Prompt Doppler ultrasonography to aid in diagnosis is often key to managing testicular torsion, but there may be delays in access; a faster, more widely available alternative is point-of-care ultrasonography (POCUS). The purpose of this study was to develop and evaluate a scrotal POCUS curriculum for urology and emergency medicine residents. Methods: Content experts in urology, emergency medicine and diagnostic imaging collaborated in a modified Delphi method to design a practical didactic curriculum for scrotal POCUS for the identification of testicular torsion. Training included 3 online video teaching modules and a 1-hour hands-on teaching session with standardized adult patients. We evaluated participants' competency in scrotal POCUS using a validated scale. We assessed participants' knowledge, comfort and confidence in performing scrotal POCUS before and after the intervention and at 3 months. Results: Twenty-four urology (n = 12) and emergency medicine (n = 12) residents participated in the curriculum. After hands-on practice, 23 participants (96%) were deemed competent at scrotal POCUS. Pre-post testing showed significant improvement in knowledge (mean score 63% v. 80%, p < 0.001), comfort (mean Likert score 0.6 v. 3.6, p < 0.001) and confidence (mean Likert score 1.0 v. 2.1, p < 0.001) after the intervention. These effects were maintained at the 3-month assessment. Conclusion: The scrotal POCUS curriculum was effective and acceptable to both urology and emergency medicine residents. The findings suggest that scrotal POCUS can be learned effectively through a short hands-on session and didactic instruction.

Contexte: Le diagnostic rapide d'une torsion testiculaire à l'aide d'une échographie Doppler est souvent crucial à la prise en charge de ce trouble. Or, comme l'accès à cet examen peut être limité, l'échographie portable constitue une solution de rechange rapide et largement accessible. La présente étude visait la mise au point et l'évaluation d'un programme de formation sur l'échographie portable scrotale destiné aux résidents en urologie et en médecine d'urgence. Méthodes: Des experts en urologie, en médecine d'urgence et en imagerie diagnostique se sont servis d'une méthode Delphi modifiée pour concevoir un programme de formation sur l'échographie portable visant à faciliter le diagnostic de la torsion testiculaire. Ce programme comprenait 3 modules d'apprentissage vidéo en ligne, ainsi qu'une séance pratique d'une heure auprès de patients adultes normalisés. Nous avons évalué les compétences des participants en matière d'échographie portable scrotale au moyen d'une échelle validée. Nous avons également évalué les connaissances, l'aisance et le niveau de confiance des participants à l'égard de cet examen avant et immédiatement après la formation, puis 3 mois plus tard. Résultats: Au total, 24 résidents en urologie (n = 12) et en médecine d'urgence (n = 12) ont suivi le programme de formation. Après la séance pratique, 23 participants (96 %) avaient les compétences nécessaires à la réalisation d'une échographie portable scrotale. La comparaison des résultats obtenus avant et immédiatement après la formation a montré une augmentation significative des connaissances (note moyenne : 63 % c. 80 %; p < 0,001), de l'aisance (moyenne à l'échelle de Likert : 0,6 c. 3,6; p < 0,001) et du niveau de confiance (moyenne à l'échelle de Likert : 1,0 c. 2,1; p < 0,001) des participants. Les effets de la formation étaient toujours présents 3 mois plus tard. Conclusion: Le programme de formation sur l'échographie portable scrotale s'est avéré efficace et acceptable pour les résidents en urologie et en médecine d'urgence. Les résultats obtenus laissent croire qu'une formation pédagogique et une courte séance d'apprentissage pratique permettent l'enseignement efficace de l'échographie portable scrotale.

Recommendations for the Management of Incidental Hepatobiliary Findings in Adults: Endorsement and Adaptation of the 2017 and 2013 ACR Incidental Findings Committee White Papers by the Canadian Association of Radiologists Incidental Findings Working Group.

The Canadian Association of Radiologists Incidental Findings Working Group consists of both academic subspecialty and general radiologists and is tasked with adapting and expanding upon the American College of Radiology incidental findings white papers to more closely apply to Canadian practice patterns, particularly more comprehensively dealing with the role of ultrasound and pursuing more cost-effective approaches to the workup of incidental findings without compromising patient care. Presented here are the 2020 Canadian guidelines for the management of hepatobiliary incidental findings. Topics covered include initial assessment of hepatic steatosis and cirrhosis, the workup of incidental liver masses identified on ultrasound and computed tomography (with algorithms presented), incidental gallbladder findings (wall thickening, calcification, and polyps), and management of incidental biliary dilatation.

Ultrasound-guided wire localisation: a GPS for hidden head and neck tumours? A case series.

Objectives: Ultrasound-guided wire (USGW) localisation for small non-palpable tumours before a revision head and neck surgery is an attractive pre-operative option to facilitate tumour identification and decrease potential complications. We describe five cases of pre-operative USGW localisation of non-palpable head and neck lesions to facilitate surgical localisation and resection. Methods: All patients undergoing pre-operative USGW localisation for non-palpable tumours of the head and neck region at London Health and Sciences Center, London, Ontario, Canada, were included. All the USGW localisations were performed by the same interventional radiologist, and the surgeries were performed by fellowship trained head and neck surgeons. Results: Five patients were included. All patients were undergoing revision surgery for recurrent or persistent disease. All successfully underwent a pre-operative USGW localisation of the non-palpable lesion before revision surgery. All lesions were localised intra-operatively with no peri-operative complications. Conclusions: USGW localisation is a safe and effective pre-operative technique for the identification of small non-palpable head and neck tumours.

Reliability of the Endoscopic Ultrasound Ulcerative Colitis (EUS-UC) score for assessment of inflammation in patients with ulcerative colitis.

Background and study aims Endoscopic ultrasound (EUS) may be a useful modality for disease assessment and risk stratification in ulcerative colitis. We assessed the reliability of a newly developed EUS index of inflammation called the EUS-Ulcerative Colitis (EUS-UC) score. Patients and methods The EUS-UC score components include total wall thickness, hyperemia, and depth of inflammation (DOI). Three blinded expert endosonographers assessed EUS videos of 58 patients with UC in triplicate. Intra- and inter-rater reliability of the hyperemia and DOI component scores were estimated using intra-class correlation coefficients (ICCs). Total wall thickness reliability estimates could not be assessed in this study. The ICCs were compared to the original indices from which they were derived. Results For hyperemia, the inter-class ICC was "moderate" at 0.556 (95 % CI = 0.434-0.651) and the intra class ICC was "almost perfect" at 0.884 (95 % CI = 0.835-0.920). The newly defined hyperemia score performed better than the original index from which is was derived. The DOI inter-class ICC was "fair" at 0.335 (95 % CI = 0.201-0.464), and the intra-class ICC was "substantial" at 0.732 (95 % CI = 0.642-0.802). The DOI reliability estimates were similar to the original index from which it was derived. Conclusions The hyperemia component of the EUS-UC score performed significantly better than the original index from which it was derived, but the reliability of the DOI component was suboptimal. Intra-class correlation was excellent for both components. The EUS-UC score is a promising instrument for assessment of UC and further validation is required.

Can Split Renal Volume Assessment by Computed Tomography Replace Nuclear Split Renal Function in Living Kidney Donor Evaluations? A Systematic Review and Meta-Analysis.

BACKGROUND: As part of their living kidney donor assessment, all living donor candidates complete a computed tomography (CT) angiogram, but some also receive a nuclear renogram for split renal function (SRF%). OBJECTIVE: We considered whether split renal volume (SRV%) assessed by CT can predict SRF%. DESIGN: Systematic review and meta-analysis. SETTING: Living donor candidates undergoing evaluation as potential living kidney donors. PATIENTS: Living donor candidates who received both a nuclear renogram for split function and CT for SRV as part of their living donor work-up. MEASUREMENTS: Split renal volume from CT scans and SRF from nuclear renography. METHODS: We performed a systematic review and meta-analysis of the literature, abstracting data and digitizing plots where possible. We searched Medline, EMBASE, and the Cochrane Library. We added data from donor candidates assessed in London, Ontario from 2013 to 2016. We used fixed and random-effects models to pool Fisher's z-transformed Pearson's correlation coefficient (r). We conducted random-effects meta-regression on digitized and aggregate data. Studies were restricted to living kidney donors or living donor candidates. RESULTS: After pooling 19 studies (n = 1479), we obtained a pooled correlation of r = 0.74 (95% confidence interval [CI] = 0.61-0.82). By linear regression using individual-level data, we observed a 0.76% (95% CI = 0.71-0.81) increase in SRF% for every 1% increase in SRV%. Split renal volume had a specificity of 88% for discriminating SRF at a threshold that could influence the decision of which kidney is to be removed (between-kidney difference ≥10%). Predonation SRV and SRF both moderately predicted kidney function 6 to 12 months after donation: r = 0.75 for SRV and r = 0.73 for SRF; Δr = 0.05 (-0.02, 0.13). LIMITATIONS: Most studies were retrospective and measured SRV and SRF only on selected living donor candidates. Efficiency gains in removing the SRF from the evaluation will depend on the transplant program. CONCLUSION: Split renal volume has the potential to replace SRF for some candidates. However, it is uncertain whether it can do so reliably and routinely across different transplant centers. The impact on clinical decision-making needs to be assessed in well-designed prospective studies. TRIAL REGISTRATION: The digitized data are registered with Mendeley Data (doi10.17632/dyn2bfgxxj.2).

CONTEXTE: Dans le cadre de leur évaluation comme donneur, tous les candidats au don de rein vivant passent une angiographie par tomodensitométrie (CT), mais certains sont également soumis à un rénogramme nucléaire qui mesure la fonction rénale séparée (% de la FRS). OBJECTIF: Nous souhaitions vérifier si le volume rénal séparé (% du VRS) évalué par tomodensitométrie pouvait prédire le pourcentage de la FRS. TYPE D'ÉTUDE: Une revue systématique et une méta-analyse. CADRE: Évaluation des candidats au don d'un rein de leur vivant. SUJETS: Les candidats au don d'organes vivants qui, dans le cadre de leur évaluation, ont été soumis à un rénogramme nucléaire (mesure de la FRS) et à une tomodensitométrie (mesure du VRS). MESURES: Le volume rénal séparé mesuré par tomodensitométrie et la fonction rénale séparée mesurée par rénogramme nucléaire. MÉTHODOLOGIE: Nous avons effectué une revue systématique et une méta-analyse de la littérature sur Medline, EMBASE et Cochrane Library dont nous avons extrait les données et, dans la mesure du possible, numérisé les schémas. Les données des candidats donateurs évalués à London, en Ontario, entre 2013 et 2016 ont été ajoutées. Nous avons utilisé des modèles à effets fixes et aléatoires pour regrouper la transformation de Fisher du coefficient de corrélation de Pearson (r). Nous avons procédé à une méta-régression des données numérisées et agrégées. Les études ont été limitées aux donneurs vivants d'un rein ou aux candidats au don d'organes vivants. RÉSULTATS: Après la mise en commun de 19 études (n = 1 479 sujets), nous avons obtenu une corrélation combinée (r) de 0,74 (IC à 95 %: 0,61-0,82). Par régression linéaire, en utilisant les données individuelles, nous avons observé une augmentation de 0,76 % (IC à 95 %, 0,71-0,81) du pourcentage de la FRS pour chaque augmentation de 1 % du VRS. Ce dernier présentait une spécificité de 88 % pour la discrimination de la FRS à un seuil qui pourrait influencer la décision dans le choix du rein à retirer (différence entre les reins ≥ 10 %). Le VRS et la FRS pré-don se sont tous deux avérés modérément sensibles pour prédire la fonction rénale six à douze mois après le don: r = 0,75 pour le VRS et r = 0,73 pour la FRS; Δr = 0,05 [-0,02 à 0,13]. LIMITES: La plupart des études retenues étaient rétrospectives et ne mesuraient le VRS et la FRS que pour certains candidats. Les gains d'efficacité obtenus en supprimant la mesure de la FRS de l'évaluation dépendront du programme de transplantation. CONCLUSION: La mesure du VRS pourrait remplacer la mesure de la FRS chez certains candidats. On ignore toutefois s'il est possible de le faire de manière fiable et systématique dans différents centres de transplantation. L'impact de ce remplacement sur la prise de décision clinique doit être évalué dans le cadre d'études prospectives bien conçues.

Full left ventricle quantification via deep multitask relationships learning.

Cardiac left ventricle (LV) quantification is among the most clinically important tasks for identification and diagnosis of cardiac disease. However, it is still a task of great challenge due to the high variability of cardiac structure across subjects and the complexity of temporal dynamics of cardiac sequences. Full quantification, i.e., to simultaneously quantify all LV indices including two areas (cavity and myocardium), six regional wall thicknesses (RWT), three LV dimensions, and one phase (Diastole or Systole), is even more challenging since the ambiguous correlations existing among these indices may impinge upon the convergence and generalization of the learning procedure. In this paper, we propose a deep multitask relationship learning network (DMTRL) for full LV quantification. The proposed DMTRL first obtains expressive and robust cardiac representations with a deep convolution neural network (CNN); then models the temporal dynamics of cardiac sequences effectively with two parallel recurrent neural network (RNN) modules. After that, it estimates the three types of LV indices under a Bayesian framework that is capable of learning multitask relationships automatically, and estimates the cardiac phase with a softmax classifier. The CNN representation, RNN temporal modeling, Bayesian multitask relationship learning, and softmax classifier establish an effective and integrated network which can be learned in an end-to-end manner. The obtained task covariance matrix captures the correlations existing among these indices, therefore leads to accurate estimation of LV indices and cardiac phase. Experiments on MR sequences of 145 subjects show that DMTRL achieves high accurate prediction, with average mean absolute error of 180 mm2, 1.39 mm, 2.51 mm for areas, RWT, dimensions and error rate of 8.2% for the phase classification. This endows our method a great potential in comprehensive clinical assessment of global, regional and dynamic cardiac function.