Competent sonography is thought to include a unique combination of skills not yet fully defined. This presents challenges when recruiting the correct people for training. Skills are thought to include visuospatial perception and psychomotor skills, but little is known about the relationship between these aptitudes and scanning ability. This feasibility study explored such relationships, to identify evaluation techniques which may improve selection and recruitment.
A sample of 30 experienced ultrasound practitioners and 30 trainees at commencement and on completion of training were administered eight tests.
No significant relationships between experienced practitioners’ or trainees’ visuospatial abilities or psychomotor abilities and scanning abilities were found. Results demonstrated that two of the visuospatial perception tests were not influenced by training and therefore, may be measuring the innate skills of ultrasound practitioners. As ultrasound practitioners had not performed any of the tests previously, ranges of scores for each of the eight tests were established for this group. This included measures for psychomotor skills which added to the current body of knowledge for sonography.
Although no significant correlations were found between participants’ visuospatial perception or psychomotor abilities and scanning ability, performance on the Obstetric Structured Assessment Test (combining all the skills required) pre-training gave the best indication of post-training scanning performance. The Obstetric Structured Assessment Test may prove a useful tool for initial assessment of potential trainees but abilities will require further investigation.
The aim of the study was to assess the accuracy of ultrasound shear wave elastography in the diagnosis of adenomyosis.
One hundred and fifty three patients were examined. Ninety-seven patients were with suspected adenomyosis and 56 patients were with unremarkable myometrium. Adenomyosis was confirmed in 39 cases (A subgroup) and excluded in 14 cases (B subgroup) in the main group based on morphological examination. All patients underwent ultrasound examination using an Aixplorer (Supersonic Imagine, France) scanner with application of shear wave elastography during transvaginal scanning. Retrospective analysis of the elastography criteria against the findings from morphological/histological examination was performed.
The following values of Young’s modulus were found in subgroup A (adenomyosis): Emean – 72.7 (22.6–274.2) kPa (median, 5–95th percentiles), Emax – 94.8 (29.3–300.0) kPa, SD – 9.9 (2.6–26.3) kPa; in subgroup B (non adenomyosis) – 28.3 (12.7–59.5) kPa, 33.6 (16.0–80.8) kPa, 3.0 (1.4–15.6) kPa; in the control group – 24.4 (17.9–32.4) kPa, 29.8 (21.6–40.8) kPa, 2.3 (1.3–6.1) kPa, respectively (P < 0.05 for all comparison with subgroup V and the control group). The Emean cut-off value for adenomyosis diagnosis was 34.6 kPa. The sensitivity, specificity, positive predictive value, negative predictive value and area under curve (AUC) were 89.7%, 92.9%, 97.2%, 76.5% and 0.908. The Emax cut-off value was 45.4 kPa (89.7%, 92.9%, 97.2%, 76.5% and 0.907, respectively).
This study showed a significant increase of the myometrial stiffness estimated with shear wave elastography use in patients with adenomyosis.
The objective of this review was to assess the effectiveness of intrapartum ultrasonography in measuring cervical dilatation, head station and position. Electronic literature searches were carried out of MEDLINE, CINAHL, and Web of Knowledge, plus manual reference list checks of all relevant articles. All published prospective studies comparing intrapartum ultrasonography with digital VE in the determination of cervical dilatation, head station and position were then evaluated for the success rate and level of agreement between ultrasonography and digital VE. Ultrasonography had higher success rate than digital VE in the determination of fetal head position, with a statistically significant difference in the first stage of labour. Second, although the successful determination of cervical dilatation was in favour of digital VE, the difference was not statistically significant. In addition, there was high agreement between ultrasound and digital VE findings on cervical dilatation. Lastly, a significant but moderate correlation between digital VE and ultrasound methods was found in the assessment of fetal head station. However, no meta-analysis could be done for the fetal head station due to the methodological differences between ultrasound anatomical landmarks and that of digital VE. The findings suggest that ultrasonography is superior to digital VE in the assessment of fetal head position, but has moderate correlation with digital VE in the assessment of head station. It also showed high agreement with digital VE in the assessment of cervical dilatation with no statistically significant difference in terms of success rate.
In response to an ultrasound imaging issue with transoesophageal echocardiography probes, a testing protocol was developed to check features pertinent to the operation of these probes. The imaging problem was detected in multiple probes of the same make and model.
Over a two-year period, a series of 26 probes of this model were tested at acceptance, then three to six months later before being replaced due to a defect. A range of visual, mechanical and electrical tests were performed. Image tests comprised low-contrast penetration measurements and a comparison of phantom images at regular intervals to highlight artefacts in both B-mode and colour Doppler imaging.
Of the 26 defective probes replaced, 7 suffered mechanical/electrical problems, 5 of which prevented imaging results being obtained. Low-contrast penetration reduction of greater than 5% occurred in 14 probes. B-mode artefacts were observed on 12 probes and Doppler noise artefacts on 6 probes. No faults were found on five probes. The manufacturer addressed the imaging problem identified and of the seven subsequent probes supplied, only one suffered an imaging fault.
The implementation of a quality assurance protocol for transoesophageal echocardiography probes resulted in cost savings on replacements/repairs. When provided with the evidence gathered, the manufacturer supplied 23 probes under warranty or as loan equipment. The regular testing of the probes substantially reduced the impact of downtime and poor diagnosis from this equipment on the clinical service.
The implementation of quality assurance for ultrasound scanners in the United Kingdom is patchy, but government appointed bodies require quality assurance and there are regulatory requirements for maintenance and inspection of equipment. Previous studies have shown high fault rates in ultrasound probes; some of these studies used electronic probe testers, but there is good evidence that over 90% of faults may be detected using simple methods. We aimed to conduct a multicentre survey of the condition of probes, using visual inspection and assessing the in-air reverberation.
Visitors to the stand run by Multi-Medix Ltd at the BMUS Annual Scientific Meeting in 2014 were invited to participate in the study. One or both of the authors visited participants, performing a visual inspection of probes for evidence of damage or wear and inspecting the in-air reverberation pattern for uniformity. Probes were classified using a risk-based traffic light system: green—no fault found; amber—fault found; further action required but the probe need not be removed from use; red—the probe should be removed from use due to physical or clinical diagnostic risks.
Twelve sites and 219 probes were included in the survey. Sixty-three percent of probes were classified as green; 25% as amber and 13% as red.
More than one in three probes were faulty. Simple tests, at minimal cost, have the potential to demonstrate over 90% of probe faults, making it possible for employers to comply with their duties defined by regulations, national standards and professional guidelines.
Real-time ultrasound imaging is an established objective outcome measurement with proven reliability. However, it is still largely biased by user-ability. Published research in the area of real-time ultrasound imaging reliability in the cervical region and in particular the deep cervical flexors is quite sparse. The purpose of this investigation was to examine if a novice ultrasound user could agree favourably with an experienced ultrasound sonographer in measuring the cross-sectional area of the longus colli.
Ultrasound images were captured from 22 healthy subjects on two different occasions, one week apart, by a novice ultrasound user. They were acquired using a GE Healthcare LOGIQe ultrasound machine, at a depth of 3–4 cm with the transducer frequency set to 8 MHz, in line with previous research guidelines. Cross-sectional area was then measured on-screen by both a novice and experienced ultrasound user to determine inter-rater reliability. Intra-rater reliability was also analysed using cross-sectional area figures from days one and two.
Intra-rater reliability for real-time ultrasound imaging for the cross-sectional area of the longus colli was "excellent" (intra-class correlation 0.90, 95% CI 0.82–0.95). Inter-rater reliability was "moderate" but in keeping with previous published research (intra-class correlation 0.61, 95% CI 0.37–0.77).
Difficulties in identifying the borders of the longus colli muscle due to its deep anatomical location and surrounding structures make it difficult for assessors to agree favourably on cross-sectional area measurements, leading to "moderate" levels of inter-rater reliability and poor agreement. Intra-rater reliability is excellent, and in this instance indicates that a novice user can be just as reliable as a more experienced ultrasound user.
The aim of the study was to evaluate whether the twinkle artefact is a valuable feature in the sonographic diagnosis of superficial epidermoid cysts.
A retrospective search was undertaken of our institution’s Radiology Information System and pathology database to identify cases of superficial masses showing the twinkle artefact that proceeded to surgical excision.
Eighteen superficial masses demonstrating the twinkle artefact were identified that were submitted for pathological analysis. Of these, 17 were confirmed to represent epidermoid cysts and only 1 case had an alternative diagnosis (proliferating trichilemmal cyst).
The presence of the twinkle artefact appears to be a specific and valuable ancillary sonographic feature for the diagnosis of superficial epidermoid cysts.
Tendon and synovial sheath disease is common. A method of monitoring the status of tendons and sheaths is important for both diagnosis of pathology and evaluation of the efficacy of treatments. For this study, an ultrasound scoring tool was developed and its reliability tested between raters. The tool is novel in that it scores tendons and sheaths separately, an important consideration since disorders of these structures are not necessarily concurrent.
Thirty diseased tendons and sheaths were included in this pilot cross-sectional study. Tendon and sheath measurements were taken and the semi-quantitative five-grade score was applied to assess tendon greyscale, tendon Doppler activity and sheath Doppler activity. Inter-rater and intra-rater agreement exercises were undertaken to test the reliability of the scoring tool.
The Intra-class Correlation Coefficient values for both the inter-rater and intra-rater reliability tests showed excellent agreement for the tendon and sheath measurements. Unweighted kappa estimations for inter-rater scores showed excellent agreement for tendon Doppler; good agreement was shown for scoring sheath Doppler, while poor agreement was shown for tendon grey-scale scoring. The intra-rater reliability scores demonstrated similar results.
Overall, the study strongly supports the use of this scoring tool for the diagnosis and follow-up of tendon and sheath disorders. The results may be used as a starting point from which to base further work in this important area. Future studies should address the limitations found in this research with a strong focus on improving tendon grey-scale measurement accuracy and agreement.
Obstetric ultrasound scans may fail to provide all the information that is needed because of poor visualisation. Two main causes of poor visualisation are addressed. These are poor foetal position and poor quality imaging due to beam distortion by overlying fatty tissue.
To improve communication with patients attending obstetric scans, a poster and leaflet were designed to explain these causes of inadequate scans. A questionnaire was used to assess the value of the poster.
57/66 (86%) questionnaires were completed. 52 (91%) found the information on the poster was helpful and well explained. For 8 (14%) the information changed their thoughts about the scan.
Clear communication aids the expectant mothers understanding of why scans may be suboptimal. The way this is recorded in the scan results is discussed.
Using ultrasound for detecting soft tissue foreign bodies seems to be the preferred choice with minimum invasion and easy availability at the bedside in emergency departments. In this study, a workshop (1 hour of lecture presentation and 3 hours of interactive hands-on) was designed to evaluate the efficacy of a short course of simple interactive training to improve the ability of emergency medicine residents to detect foreign bodies with ultrasound. Eight pieces of fresh full thickness (10 x 10 x 10 cm) lamb leg muscle were used in this study. Five different types of foreign bodies, including: a piece of glass (5 x 5 x 4 mm), wood (5 x 5 x 4 mm), gravel (5 mm diameter), plastic (5 x 5 x 2 mm) and a nail (25 mm in length) were placed deep inside each lamb leg. An ultrasound machine with a 7.5 MHz linear probe was used in this study. 35 emergency medicine residents (12 PGY1, 11 PGY2 and 12 PGY3) were enrolled in this study. Pretest and post-test results were compared and analyzed. Among all 35 participants in the training session, foreign body detection was significantly improved after the workshop (p < 0.001). Overall sensitivity and specificity for differentiating the presence and absence of a foreign body with 95% confidence were 60% (75% for PGY3) and 85.7% (91.7% for PGY3), respectively. The overall accuracy increased from 20.2% to 72.8% due to this session. This study supported the possibility of using ultrasound to detect foreign bodies by emergency physicians with a very short training course. This is highly beneficial for overcrowded emergency departments.
Ultrasound is widely used as a screening tool in obstetrics with the aim of reducing maternal and foetal morbidity. However, to be effective it is recommended that scanning services follow standard protocols based on national guidelines and that scanning practice is audited to ensure consistency. Bradford has a multi-ethnic population with one of the highest rates of birth defects in the UK and it requires an effective foetal anomaly screening service. We implemented a rolling programme of audits of dating scans, foetal anomaly scans and growth scans carried out by sonographers in Bradford. All three categories of scan were audited using measurable parameters based on national guidelines. Following feedback and re-training to address issues identified, re-audits of dating and foetal anomaly scans were carried out. In both cases, sonographers being re-audited had a marked improvement in their practice. Analysis of foetal abnormality detection rates showed that as a department, we were reaching the nationally agreed detection rates for the Fetal Anomaly Screening Programme auditable conditions. Audit has been shown to be a useful and essential process in achieving consistent scanning practices and high quality images and measurements.
The aims of the study were to evaluate whether three-dimensional transvaginal ultrasound (3D TV US) is superior to two-dimensional transvaginal ultrasound (2D TV US) at visualising intrauterine devices and determining their position. This prospective study included 52 participants with an intrauterine device fitted, who underwent 2D TV US and 3D TV US. 2D TV US and 3D-reconstructed coronal images were reviewed by two gynaecological radiologists to assess ease of visualisation and position of the intrauterine devices. Statistical analysis was performed using Wilcoxon signed-rank, McNemar and Chi-squared tests. The inter-observer agreement was measured using Cohen’s Kappa. Intrauterine device visualisation scores were significantly higher with 2D TV US compared with 3D TV US (Radiologist 1 p = <0.001, Radiologist 2 p = 0.007). A significant number of T-arms appeared to perforate into the adjacent myometrium on the 3D-reconstructed coronal image, but were normal on the 2D images (Radiologist 1 p = <0.001, Radiologist 2 p = 0.008). Radiologist 1 found 19 perforated T-arms on 3D TV US compared with four on 2D TV US. Radiologist 2 found 13 perforated T-arms on 3D TV US compared with five on 2D TV US. Both radiologists agreed on the positions of the intrauterine devices substantially with 3D TV US (Kappa = 0.69) and moderately with 2D TV US (Kappa = 0.55). The 3D TV US did not visualise an intrauterine device better than 2D TV US. The 3D-reconstructed coronal image of the uterus can reliably display cases of T-arm perforation into the adjacent myometrium, which could be missed on 2D TV US images. The 3D TV US should be used in addition to 2D TV US in all cases where an intrauterine device is under evaluation.
Ultrasound equipment is known to act as a reservoir for potentially pathogenic organisms. The aims of these studies were to establish current cleaning practices, to review the extent of bacterial contamination of ultrasound equipment in our hospital, to establish an effective cleaning regimen and to ensure that cleaning does not cause damage. A questionnaire was sent to all acute NHS hospitals in England to establish current cleaning practices. A review of our current practice was performed to establish the extent of bacterial contamination of ultrasound equipment currently in use. Laboratory studies compared cleaning the probes with soap and water with decontaminating with a chlorhexidine 2% and alcohol 70% wipe, including quantifying the residual effect. Accelerated aging was performed on the probe and staff surveyed to establish potential problems with using the wipes on the probe. The survey revealed that a variety of cleaning methods were used to decontaminate ultrasound probes; 57% of our ultrasound machines were contaminated with bacteria. The laboratory studies showed superiority of the chlorhexidine and alcohol wipes over soap and water due to a residual effect, both immediately after cleaning and after 24 hours. The staff survey demonstrated no apparent change in function of the probe after cleaning with the chlorhexidine wipes. Cleaning ultrasound probes with chlorhexidine and alcohol wipes is effective and provides additional protection against bacterial contamination due to its residual effect, and appears in the short term to have no detrimental effect on the probe.
Technological developments are impacting on many aspects of life, including education. One particular area of technology where there is growing interest within higher education institutions (HEIs) offering healthcare training is the use of simulators. The literature shows diverging views on the role of simulated learning in healthcare and further evaluation is needed to explore the quality of learning opportunities that are offered, and their effectiveness in the preparation of students for clinical practice. A qualitative study was undertaken, using interviews to explore the experiences of a group of sonography students after interacting with an ultrasound simulator. Simulation was positively evaluated by students in this study. The findings confirm that simulated learning enables students to be interactive learners rather than being passive recipients of knowledge. Simulated learning provides learning opportunities in a risk free environment, which reduces stress for the student and potential harm to patients. Confidence levels were increased, thereby improving future clinical scanning experiences for both the student and their patients. Suggestions were made for the more effective integration of simulated learning into the curriculum. Continued research into simulation, teaching and learning practices needs to occur if we are to ensure maximum advantage of the simulation experience.
Postoperative complications associated with endovascular aneurysm repair (EVAR) mandate the need for lifelong surveillance. The aim of this audit was to compare the detection rates of endoleaks during the first 10 months of a combined sonographer-led colour Doppler ultrasound (CDUS) and radiologist-led contrast-enhanced computed tomography (CECT), postoperative EVAR surveillance programme, within a single National Health Service Hospital.
A prospective audit was carried out of all patients with EVAR, who had same-day CECT and CDUS surveillance examinations between March 2010 and January 2011. CECT examinations were reported by three consultant vascular radiologists. Of 66 CDUS examinations, 64 (97%) were performed and reported by four certified vascular sonographers. The reports of dual-modality, same-day scans were compared, to establish agreement on the presence and classification of the type, or absence of endoleaks. CECT was used as the gold standard, against which the sensitivity and specificity of CDUS in endoleak detection was determined.
Sixty-six paired same-day CECT and CDUS reports were compared. Ten endoleaks were identified by CECT (15% incidence) and eight (80%) of 10 were type II. The number of observed agreements was 58 (88%) of 66; CDUS missed six endoleaks (five type II) and suggested two false-positives. CDUS had a sensitivity of 40% and a specificity of 96%.
In our study, CDUS demonstrated an excellent specificity but had a low sensitivity for endoleak detection. We agree CDUS cannot effectively replace CECT as the sole imaging modality. Research to determine an international consensus for an effective and efficient postoperative EVAR surveillance patient pathway is required.
Inguinal hernia is the most common surgical repair performed in England with more than 73,000 cases in 2007. The majority of inguinal hernias are diagnosed clinically, but ultrasound is fast becoming the imaging modality of choice for diagnosing occult hernia, due to its non-invasive nature and lack of radiation. At the Norfolk and Norwich University Hospitals NHS Foundation Trust, ultrasound of the groin was performed only by radiologists, but recently sonographers have also begun examining patients for inguinal hernia. This study investigates the accuracy of ultrasound diagnosis of hernia and compares the performances of radiologists and sonographers over a nine-month period involving 124 patients. Our results indicate that both professional groups have a high detection rate and that there is no significant difference in accuracy. An incidental finding was that many general practitioner referrals diagnosed with an inguinal hernia did not proceed to surgery. Since many ultrasound departments are experiencing demand versus capacity issues, it may be that further investigation into the value of diagnosis when surgery is unlikely is warranted.