Can live bi-plane sonography reduce work-related musculoskeletal disorders of the wrist?

OBJECTIVES: Work-related musculoskeletal disorders (WMSDs) are a recognized problem affecting up to 81% of sonographers. Live bi-plane imaging is a new technology derived from matrix transducers, which allows the operator to scan in more than one plane simultaneously and can reduce the off-axis movement of the scanning arm when assessing abdominal organs. This study was performed to assess if using a bi-planar technique would reduce stressful movements of the wrist. METHODS: Twelve patients were scanned by three operators (four each) using both a standard scanning abdominal protocol and a live bi-plane abdominal protocol using an iu22 scanner (Philips Healthcare, Bothell, WA) and an X6-1 probe with a bi-axial flexible electrogoniometer measuring the postural stresses on the scanning wrist throughout the study. RESULTS: Significant flexion/extension and radial/ulnar deviations were markedly reduced using the bi-plane scanning protocol compared to the standard B-mode protocol, with an average reduction in significant repetitive wrist movements of 71.6% (p = <0.001). CONCLUSIONS: Bi-planar ultrasound scanning technique may reduce stressful movements on the scanning arm and might reduce the likelihood of WMSD assuming there are no other contributing factors.

Rapid assessment of abdominal aortic aneurysms by 3-dimensional ultrasonography.

OBJECTIVE: The purpose of this study was to assess the application and accuracy of 3-dimensional (3D) volume acquisition ultrasonography in the measurement of abdominal aortic aneurysms (AAAs). METHODS: Thirty consecutive patients undergoing surveillance ultrasonographic examinations of known AAAs were scanned according to a conventional protocol, after which 3D volume data sets were acquired with a commercially available mechanical transducer. Maximum aortic diameters were measured with multiplanar reconstructions from the 3D volume data, and these were compared with those from the conventional technique. RESULTS: Abdominal aortic aneurysm diameters were between 2.9 and 6.75 cm. For both anteroposterior and transverse diameters, a paired t test showed a Pearson correlation coefficient of 0.98 (significant at the P = .01 level) and a coefficient of determination of 0.96. Bland-Altman analysis showed that the mean difference between the two sets of measurements was very close to 0 (P = .05). Thus, there was no significant difference between the conventional and 3D volume measurement methods. The scan acquisition time for the 3D volume data was only 3 seconds for each set (anteroposterior and transverse). CONCLUSIONS: Three-dimensional ultrasonography using volume acquisition offers a new opportunity to acquire fast and reliable AAA measurements. The reduced scan times can be used to allow greater patient throughput and will help cope with the increasing workload of AAA surveillance. By archiving a complete set of data, 3D ultrasonography allows subsequent analysis and comparison of measurements. This study also suggests that the technique could be used for other applications with similar efficiency gains.

Testicular sonography: Is an echogenic ring a sign of a benign lesion?

The differentiation of benign from malignant testicular lesions is important to avoid unnecessary surgical intervention but is often difficult, particularly in the case of focal hypoechoic lesions. We present the description of 3 cases of an echogenic ring that appeared around a hypoechoic testicular mass on sonograms. The ring proved to be a fibrous capsule around a benign lesion. If these observations are confirmed in larger series, the sonographic pattern described here may help reduce the number of orchiectomies performed for benign lesions.

Appraising surgeons learning sonography: measuring measurement variability.

PURPOSE: Sonography is increasingly used by various clinicians in several task-specific situations. We present a method of assessing 1 aspect of a nonspecialist's ability in performing sonography, measurement variability. METHODS: An experienced radiologist and a surgeon who had received 4 weeks of sonography training each made triplicate measurements of gallbladder dimensions in 19 adult patients undergoing abdominal sonography. The observers examined the subjects in immediate succession using the same ultrasound equipment and were blinded to each other's measurements until the end of the study. Intraobserver measurement variability rates were calculated for gallbladder length, height, and width by using analysis of variance techniques and were expressed as a within-subject standard deviation and a repeatability coefficient. RESULTS: In terms of intraobserver measurements, the estimated within-subject standard deviations were comparable for the radiologist and the surgeon (length, 0.22 versus 0.17 cm; height, 0.14 versus 0.14 cm; and width, 0.12 versus 0.14 cm, respectively), as were the repeatability coefficients. The interobserver variability showed good agreement as well; the estimated within-subject standard deviations (and 95% limits of agreement) obtained were length, 0.47 cm (-1.08 to 1.48 cm); height, 0.34 cm (-1.08 to 0.49 cm); and width, 0.28 cm (-0.80 to 0.81 cm). CONCLUSIONS: The ability to measure organ dimensions accurately is an essential sonographic skill that can be readily appraised. The findings from this comparison study illustrate that this 1 small aspect of sonography can be learned by various clinicians and that their ability in this task can be appraised. In a clinical setting, the small degree of variability in measurements made by the experienced radiologist and the sonography-trainee surgeon is likely to be satisfactory.

The role of strain gauge plethysmography in the assessment of patients with suspected deep vein thrombosis.

Suspicion of deep vein thrombosis (DVT) is a common reason for medical referral to hospital. Clinical signs and symptoms are notoriously unreliable, hence there is the need for objective testing. Strain gauge plethysmography (SGP) has been marketed as a technique for excluding lower limb DVT. We therefore set out to evaluate this screening tool. Over a 2 year period, 437 consecutive patients referred with suspected DVT were assessed using both plethysmography and Doppler ultrasound. When the two techniques were compared, plethysmography was found to have a negative predictive value of 90%. We conclude that strain gauge plethysmography has a role in the screening of patients with suspected DVT but should not be used as the sole method in patient assessment.