Ultrasound learning curve in gout: a disease-oriented training program

Ultrasound assessment of Achilles enthesitis: a dedicated training program

OBJECTIVE

To describe an intensive and multimodal ultrasound (US) training program focused on Achilles enthesitis and to illustrate the learning curve of trainees without experience.

METHODS

Three medical students (trainees) and two rheumatologists experienced in musculoskeletal US (trainers) were involved in the training program, which encompassed one preliminary theoretical-practical meeting and five scanning sessions (two patients per session). The students and one expert performed the US examination of the Achilles enthesis bilaterally. The trainees acquired representative images and assessed the presence of Outcome Measures in Rheumatology (OMERACT) US abnormalities of enthesitis. The experts provided feedback addressing trainees' misinterpretations, and the quality of the acquired images was evaluated. A dedicated questionnaire was used to evaluate the students' confidence. After each session, five sets of static images (total=100 images of most commonly scanned entheses) were provided and scored by the students according to OMERACT US definitions. Total agreement and prevalence and bias adjusted kappa (PABAK) were used to evaluate the concordance between the trainees and the expert sonographer.

RESULTS

The total agreement and PABAK significantly improved between the first and fifth scanning sessions (76.2% versus 92.9%, p<0.01, and 0.5 versus 0.79, p<0.01) and between the first and fifth static image sets (64.5% versus 81.9%, p<0.01, and 0.29 versus 0.74, p<0.01). Image quality did not significantly improve (p=0.34). A significant increase in trainees' confidence was registered (p<0.01).

CONCLUSIONS

The described training program rapidly improved the students' performance in the US assessment of Achilles enthesitis, appearing to be an effective starting model for the future development of pathology-oriented teaching programs for the US in rheumatology.

Solid validity evidence for two tools assessing competences in musculoskeletal ultrasound: a validity study

OBJECTIVES

Musculoskeletal ultrasound (MSUS) is increasingly used by rheumatologists in daily clinical practice. However, MSUS is only valuable in trained hands, and assessment of trainee competences is therefore essential before independent practice. Thus, this study aimed to establish validity evidence for the EULAR and the Objective Structured Assessment of Ultrasound Skills (OSAUS) tools used for assessing MSUS competences.

METHODS

Thirty physicians with different levels of MSUS experience (novices, intermediates, and experienced) performed four MSUS examinations of different joint areas on the same rheumatoid arthritis patient. All examinations were video recorded (n = 120), anonymized, and subsequently assessed in random order by two blinded raters using first the OSAUS assessment tool followed by the EULAR tool 1 month after.

RESULTS

The inter-rater reliability between the two raters was high for both the OSAUS and EULAR tools, with a Pearson correlation coefficient (PCC) of 0.807 and 0.848, respectively. Both tools demonstrated excellent inter-case reliability, with a Cronbach's alpha of 0.970 for OSAUS and 0.964 for EULAR. Furthermore, there was a strong linear correlation between the OSAUS and the EULAR performance scores and the participants' experience levels (R2 = 0.897 and R2 = 0.868, respectively) and a significant discrimination between different MSUS experience levels (P < 0.001 for both).

CONCLUSIONS

MSUS operator competences can be assessed reliably and valid using either the OSAUS or the EULAR assessment tool, thereby allowing a uniform competency-based MSUS education in the future. Although both tools demonstrated high inter-rater reliability, the EULAR tool was superior to OSAUS.

TRIAL REGISTRATION

ClinicalTrials.gov, http://clinicaltrials.gov, NCT05256355.

Reliability of point-of-care ultrasound for measuring quadriceps femoris muscle thickness

BACKGROUND

Point-of-care ultrasound can be used to assess muscle thickness. However, its reliability has not been fully evaluated.

AIM

This study aimed to assess the intrarater and inter-rater reliability of point-of-care ultrasound for the estimation of quadriceps and rectus femoris thickness in patients from a rehabilitation setting.

DESIGN

This is a cross-sectional study.

SETTING

This study was conducted at the Department of Physical Medicine and Rehabilitation of a tertiary care hospital.

POPULATION

Twenty-nine inpatients consecutively selected after admission.

METHODS

Four observers, two trained and two untrained, used point-of-care ultrasound to measure quadriceps femoris and rectus femoris thickness. Each observer performed two measurements followed by a second set of two measurements three hours later. Intraclass correlation coefficients (ICC) were then calculated.

RESULTS

Both intrarater and inter-rater ICC were higher than 0.888 for both quadriceps and rectus femoris measurements. Reliability was highest when ICC were calculated based on the average of two measurements, with the intrarater ICC being of 0.956 (95% CI: 0.937-0.970) for rectus femoris and of 0.966 (95% CI: 0.951-0.976) for quadriceps femoris; and with the inter-rater ICC being of 0.919 (95% CI: 0.863-0.957) for rectus femoris and 0.945 (95% CI: 0.907- 0.971) for quadriceps femoris. Trained and untrained observers did not have significantly different ICC values.

CONCLUSIONS

These results suggest that point-of-care ultrasound is a reliable option to measure muscle thickness of knee extensors by the same or different observers.

CLINICAL REHABILITATION IMPACT

Measuring knee extensors thickness may aid to adequately modulate treatment choices in patients with disability. This study suggests that quadriceps and rectus femoris muscle thickness measured after a short training course, by either an experienced or inexperienced clinician, presents high reliability. Reliability can be increased if the average of two measurements is used. Besides being inexpensive and portable, point-of-care ultrasound is a reliable tool for measuring knee extensors' thickness, rendering it potentially adequate to be used in clinical practice.

Training and assessment of musculoskeletal ultrasound and injection skills-a systematic review

OBJECTIVES

To examine how residents are trained and assessed in musculoskeletal ultrasound (MSUS), MSUS-guided and landmark-guided joint aspiration and injection. Additionally, to present the available assessment tools and examine their supporting validity evidence.

METHODS

A systematic search of PubMed, Cochrane Library, and Embase was conducted in accordance with the PRISMA guidelines and studies published from January 1, 2000 to May 31, 2021 were included. Two independent reviewers performed the search and data extraction. The studies were evaluated using the Medical Education Research Quality Instrument (MERSQI).

RESULTS

9,884 articles were screened, and 43 were included; 3 were randomized studies, 21 pre- and post-test studies, 16 descriptive studies, and 3 studies developing assessment tools. The studies used various theoretical training modalities e.g. lectures, anatomical quizzes and e-learning. The practical training models varied from mannequins and cadavers to healthy volunteers and patients. The majority of studies used subjective "comfort level" as assessment, others used practical examination and/or theoretical examination. All training programs increased trainees' self-confidence, theoretical knowledge, and/or practical performance, however few used validated assessment tools to measure the effect. Only one study met the MERSQI high methodical quality cut-off score of 14.

CONCLUSION

The included studies were heterogeneous, and most were of poor methodological quality and not based on contemporary educational theories. This review highlights the need for educational studies using validated theoretical and practical assessment tools to ensure optimal MSUS training and assessment in rheumatology.

Sonographic estimation of monosodium urate burden predicts the fulfillment of the 2016 remission criteria for gout: a 12-month study

Objective

To investigate whether baseline monosodium urate (MSU) burden estimated by ultrasound (US) predicts the achievement of the 2016 remission criteria for gout after 12 months.

Methods

In this 12-month prospective, observational and single-center study, patients with gout fulfilling all the domains of the 2016 preliminary remission criteria for gout at baseline and on urate-lowering therapy (ULT) for at least the preceding 6 months were consecutively enrolled.

The US findings indicative of MSU deposits [aggregates, double contour (DC) sign, and/or tophi] were identified according to the Outcome Measure in Rheumatology US Working Group definitions.

The US MSU burden was estimated by evaluating elbows, wrists, 2nd metacarpophalangeal joints, knees, ankles, and 1st metatarsophalangeal joints.

Results

Remission criteria were fulfilled in 21 (42.0%) out of 50 patients at 12 months. The baseline US MSU burden was significantly lower in patients who achieved remission than in those who did not fulfill the remission criteria at 12 months (1.9±1.8 vs 5.1±3.1, p<0.01).

US scores and ongoing flare prophylaxis were the only significant predictors of remission with an odds ratio of 10.83 [(95%CI=1.14–102.59), p=0.04] for the absence of MSU deposits, 5.53 [(95%CI=1.34–22.76), p<0.01] for the absence of aggregates, 7.33 [(95%CI=1.71–31.44), p<0.01] for the absence of DC sign, 3.88 [(95%CI=1.08–13.92), p=0.04] for the absence of tophi, and 0.23 [(95%CI=0.07–0.75), p=0.02] for ongoing flare prophylaxis.

Conclusion

In gout, baseline US estimation of MSU burden is an independent predictor of the achievement of the remission criteria at 12 months.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02568-x.

Artificial Intelligence for Ultrasound Informative Image Selection of Metacarpal Head Cartilage. A Pilot Study

Objectives: This study aims to develop an automatic deep-learning algorithm, which is based on Convolutional Neural Networks (CNNs), for ultrasound informative-image selection of hyaline cartilage at metacarpal head level. The algorithm performance and that of three beginner sonographers were compared with an expert assessment, which was considered the gold standard.

Methods: The study was divided into two steps. In the first one, an automatic deep-learning algorithm for image selection was developed using 1,600 ultrasound (US) images of the metacarpal head cartilage (MHC) acquired in 40 healthy subjects using a very high-frequency probe (up to 22 MHz). The algorithm task was to identify US images defined informative as they show enough information to fulfill the Outcome Measure in Rheumatology US definition of healthy hyaline cartilage. The algorithm relied on VGG16 CNN, which was fine-tuned to classify US images in informative and non-informative ones. A repeated leave-four-subject out cross-validation was performed using the expert sonographer assessment as gold-standard. In the second step, the expert assessed the algorithm and the beginner sonographers' ability to obtain US informative images of the MHC.

Results: The VGG16 CNN showed excellent performance in the first step, with a mean area (AUC) under the receiver operating characteristic curve, computed among the 10 models obtained from cross-validation, of 0.99 ± 0.01. The model that reached the best AUC on the testing set, which we named “MHC identifier 1,” was then evaluated by the expert sonographer. The agreement between the algorithm, and the expert sonographer was almost perfect [Cohen's kappa: 0.84 (95% confidence interval: 0.71–0.98)], whereas the agreement between the expert and the beginner sonographers using conventional assessment was moderate [Cohen's kappa: 0.63 (95% confidence interval: 0.49–0.76)]. The conventional obtainment of US images by beginner sonographers required 6.0 ± 1.0 min, whereas US videoclip acquisition by a beginner sonographer lasted only 2.0 ± 0.8 min.

Conclusion: This study paves the way for the automatic identification of informative US images for assessing MHC. This may redefine the US reliability in the evaluation of MHC integrity, especially in terms of intrareader reliability and may support beginner sonographers during US training.

Sonographic assessment of calcium pyrophosphate deposition disease at wrist. A focus on the dorsal scapho-lunate ligament

OBJECTIVES

To investigate the diagnostic accuracy of ultrasound and conventional radiography in the evaluation of calcium pyrophosphate crystal deposits at wrist level.

METHODS

Consecutive patients with a "definite" diagnosis of calcium pyrophosphate deposition disease and disease-controls were prospectively included in this cross-sectional single-centre study. Scapho-lunate ligament, triangular fibrocartilage complex, and volar recess of the radio-lunate joint were explored using ultrasound, conventional radiography and computed tomography.

RESULTS

Sixty one patients and 39 disease controls were enrolled. Two-hundred wrists were evaluated using both conventional radiography and ultrasound and 26 using computed tomography. Ultrasound findings indicative of crystal deposits were found in at least one wrist in 95.1% of patients and in 15.4% of controls (P<0.001). Scapho-lunate ligament calcifications were reported in 83.6% of patients and in 5.1% of controls (P<0.001). On conventional radiography, calcifications were found in at least one wrist in 72.1% of patients and in 0% of controls (P<0.001). Using the Ryan-McCarty criteria as a gold standard, sensitivity, specificity and diagnostic accuracy were 0.72 (0.59-0.83), 1.0 (0.91-1.0) and 0.83 (0.74-0.90) for conventional radiography and 0.95 (0.86-0.99), 0.85 (0.69-0.94) and 0.91 (0.84-0.96) for ultrasound. The agreement between ultrasound and computed tomography was substantial when assessing triangular fibrocartilage complex (kappa=0.70; 0.43-0.97) and scapho-lunate ligament (kappa=0.69; 0.41-0.97), and moderate for radio-lunate joint (kappa=0.46; 0.12-0.80).

CONCLUSIONS

This study supports the diagnostic accuracy of ultrasound in evaluating wrist involvement in calcium pyrophosphate deposition disease. The inclusion of the scapho-lunate ligament in a disease-oriented scanning protocol could improve the diagnostic performance of ultrasound.

Modern Landscapes and Strategies for Learning Ultrasound in Rheumatology

Ultrasound in rheumatology is gaining increasing acceptance in the field, with its use expanding beyond the musculoskeletal system to image rheumatic disease pathology of the vasculature, salivary glands, and lungs. Fellows in training and practicing clinicians are seeking ways to attain training and competency assessment. These standards are evolving, but no uniform mechanism for training exists. Although clinicians in practice find a wide array of resources available for self-directed education in ultrasound in rheumatology, a consensus-based and publicly available training curriculum can further enhance and standardize learning. This article discusses ultrasound in rheumatology education opportunities, competency assessment, and certification pathways.

Evaluation of the Acquisition of Ultrasound Proficiency in Hand Surgery Fellows

OBJECTIVES

To evaluate hand surgery fellow ultrasound (US) evaluations and performance of clinically relevant tasks after brief instruction.

METHODS

Six hand surgery fellows completed an US assessment and a survey on US use before and 1 month after a 30-minute US course.

RESULTS

The time to obtain an adequate image decreased from 4 minutes 42 seconds (4:42; range, 3:57-7:55) to 0:52 (range, 0:30-1:14; P < .001). Participants' performance for structure identification improved from 9.7 (range, 8-13) to 12 (range, 10-13) of 14 structures (P < .05). The average time to completion decreased from 14:6 (range, 12:08-18:30) to 9:34 (range, 4:40-15:54; P < .01). After instruction, all 6 participants identified and measured the cross-sectional area of the median nerve, identified and measured a zone 3 flexor tendon gap, and identified a simulated flexor digitorum profundus avulsion and its level of retraction (P < .05). Five of 6 successfully administered an US-guided injection to the extensor carpi ulnaris subsheath.

CONCLUSIONS

After a 30-minute instructional session, hand surgery fellows can achieve a basic level of US competency.

Use of ultrasound for diagnosis and monitoring of outcomes in crystal arthropathies

PURPOSE OF REVIEW

In the latest recommendations for the diagnosis and management of gout and calcium pyrophosphate dihydrate (CPPD) crystal deposition disease, the diagnostic potential of ultrasound has been recognized. This review highlights the recent advances of research on ultrasound in gout and CPPD crystal deposition disease.

RECENT FINDINGS

Ultrasound allows highly sensitive, noninvasive and quick detection of microcrystal aggregates in multiple anatomic areas. Ultrasound can be used as a safe and reliable guide to aspirate even minimal fluid collections suitable for microscopic analysis, and as a tool for monitoring monosodium urate crystal dissolution induced by urate-lowering therapy. The first metatarsophalangeal joint and the knee should be regarded as the anatomic regions with the highest probability of being respectively positive for monosodium urate and CPPD crystal aggregates.

SUMMARY

The detection of highly evocative signs in patients with equivocal clinical findings may have a deep impact on the clinical decision-making process, narrowing the differential diagnostic spectrum and avoiding time-consuming and expensive diagnostic procedures. Ultrasound differential diagnosis between gout and CPPD crystal deposition disease is based on the characteristics of crystal aggregates and their preferential localization in different anatomical areas.

International Consensus for ultrasound lesions in gout: results of Delphi process and web-reliability exercise

OBJECTIVE

To produce consensus-based definitions of the US elementary lesions in gout and to test their reliability in a web-based exercise.

METHODS

The process consisted of two steps. In the first step a written Delphi questionnaire was developed from a systematic literature review and expert international consensus. This collated information resulted in four statements defining US elementary lesions: double contour (DC), tophus, aggregates and erosion. The Delphi questionnaire was sent to 35 rheumatology experts in US, asking them to rate their level of agreement or disagreement with each statement. The second step tested the reliability by a web-exercise. US images of both normal and gouty elementary lesions were collected by the participants. A facilitator then constructed an electronic database of 110 images. The database was sent to the participants, who evaluated the presence/absence of US elementary lesions. A group of 20 images was displayed twice to evaluate intra-reader reliability.

RESULTS

A total of 32 participants responded to the questionnaires. Good agreement (>80%) was obtained for US definitions on DC, tophus, aggregates and erosion in the Delphi exercise after three rounds. The reliability on images showed inter-reader κ values for DC, tophus, aggregates, erosion findings of 0.98, 0.71, 0.54 and 0.85, respectively. The mean intra-reader κ values were also acceptable: 0.93, 0.78, 0.65 and 0.78, respectively.

CONCLUSION

This, the first consensus-based US definition of elementary lesions in gout, demonstrated good reliability overall. It constitutes an essential step in developing a core outcome measurement that permits a higher degree of homogeneity and comparability between multicentre studies.