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Inflammatory arthritis
S2
Ultrasound in Medicine & Biology
Another common scenario is ultrasound of the adult hip for ‘trochanteric bursitis’. Multiple bursa compartments are present between and adjacent to the tendons and muscles near the greater trochanter, and thin slips of fluid in these spaces are common. Pathologically proven trochanteric bursitis is uncommon, and usually associated with pathology of the gluteal tendons. Pain at the greater trochanter is very common, especially in elderly people. ‘Trochanteric bursitis’ is best thought of as a regional pain syndrome with various causes. The dominant role for ultrasound in this context is guidance of injection of steroid and local anaesthetic. Ultrasound of soft tissue masses is common, and usually straightforward in well characterised lesions like ganglia and lipomas. Sometimes however, ultrasound is unable to provide a specific diagnosis. This should not be the end of things. Based on their ultrasound features, unknown lesions should be sorted into either ‘probably benign’ or ‘indeterminate/ possibly malignant’, and further follow up recommended, such as MRI or specialist assessment. Rotator cuff repair is an increasingly common procedure. It may be performed with an open or arthroscopic technique, which consists of reattachment of the torn tendon to the humeral head with suture anchors. Patients may present with residual or recurrent pain or dysfunction for which imaging is required. A repaired cuff tendon will probably never look completely normal on ultrasound. Heterogeneity, thinning, and small residual defects are common post repair, as are bursal fluid and bone surface irregularity. In general terms, if fibres can be followed to the suture anchors, then the repair is probably intact. Correlation of surgical technique and direct consultation with the surgeon may be required in difficult cases. Inflammatory arthritis Fred Joshua President, Australian Society for Ultrasound in Medicine (ASUM), Kogarah, NSW, Australia Inflammatory arthritis is a common problem that is often under recognised. This presentation will discuss the causes of inflammatory arthritis and what key features ultrasound imaging helps to identify that aids in diagnosis and management.
SESSION 1C: VASCULAR Angle-Independent Blood Volume Flow Jonathan M. Rubin University of Michigan Department of Radiology, University of Michigan Hospital, Ann Arbor, MI, USA Standard ultrasound Doppler can estimate volume flow. However, the estimate depends on major assumptions, which include flow that has to be perfectly symmetric around the centerline of the vessel, a perfectly round vessel cross-section, and the Doppler measurements must be angle corrected. These restrictions make volume flow estimates problematic especially in environments where these assumptions do not hold, such as transjugular intrahepatic portosystemic shunts (TIPS) and umbilical cords. With the advent of 3D/4D ultrasound imaging, all of the limitations of ultrasound volume flow measurements can be overcome, potentially producing volume flow estimates that are as easy to obtain as standard color flow Doppler images, i.e. in real time. The method depends on the something called Gauss’s theorem. This law states that volume flow is equal to the sum of all of the normal velocity vectors passing through any surface. Simply put, this sum, also known as the total flux, is just the sum of the local products of the velocity of the blood going perpendicularly through every individual element of a surface that cuts across a blood vessel This can be any continuous surface (often known as a C-surface or C-plane), it does not have to be a plane, and the
Volume 45, Number S1, 2019 method contains none of the assumptions required for standard volume flow measurement. Thus, this method is angle independent, flow profile independent, and vessel geometry independent. Hence, non-laminar flow profiles produced by the irregular TIPS stent walls or highly tortuous umbilical arteries and veins do not affect this method. We have tested this technique in simulations, phantoms, in in-vivo animal models, and human subjects. The method has proven to work well in all of these settings. In humans, linear regression of data from revised TIPS cases showed an inverse correlation between mean-normalized change in pre- and post-revision shunt volume flow and mean-normalized change in pre- and post-revision portosystemic pressure gradient (r2 = 0.71, Pvalue = 0.0044). Depth-corrected and weight normalized umbilical vein volume flow measurements in normal and pre-eclampsia subjects showed a statistically significant difference between groups (P = 0.035). Further, these measurements were highly reproducible in the mean estimate with an intra-subject relative standard error (RSE) of 12.1 § 5.9 % and an intra-measurement RSE of 5.6 § 1.9 %. This method is easy to perform, accurate, and reproducible. Using 2D ultrasound arrays, it can be in real-time. It could have a major impact on future flow analysis. Quantification of Blood Flow in 3D Ultrasound Vascular Applications J. Brian Fowlkes Departments of Radiology and Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA Vascular ultrasound has an increasing role to play in the evaluation of numerous conditions such as peripheral vascular disease (PVD). Ultrasound imaging (b-mode and elastography) has been used for evaluation of vascular walls such as for deep venous thrombus (DVT) but there is also a need for flow assessment. With the increasing incidence of PVD, particularly related to diabetes, objective measures of flow in the extremities is important in medical management of such conditions. Doppler ultrasound can provide measurements of flow but generally in the major vessels and often relying on relative metrics such as pulsatility index, resistive index, etc. Subjective assessments are made in combination with selective limb compression or other conditions that would affect flow such as a Valsalva maneuver. Methods are being developed for more quantitative flow such as microvascular flow, ultrasound-based particle image velocimetry, Doppler vector flow, and contrast enhanced ultrasound (CEUS) as well as global flow metrics such as volumetric flow. This presentation will review some of the technology advances being made in the quantification of blood flow as these relate to vascular ultrasound. Can sonographers Reliably Scan Perforator Veins? Rob McGregor,1 Rod J. McGregor,2 Angie Fearon,2 Rob Davidson2 1 USVASC Pty Ltd, Farrer, ACT, Australia, 2 University of Canberra, Faculty of Health, Canberra, ACT, Australia Introduction: Diagnostic Ultrasound (DU) plays an integral role in the assessment and mapping of Chronic Venous Insufficiency (CVI) (Neglen & Raju, 1992; Zygmunt, 2014) and in particular the assessment and documentation of perforator veins.(Eidson Iii & Bush, 2010). Also evident is a paucity of research around the reliability and validity of sonographer measurement, in particular for vascular ultrasound. The overall research aim is to develop a tool to measure reliability and validity between sonographers in the assessment of perforator veins. The outcome will be then to implement that tool within a group of experienced vascular sonographers.
Ultrasound in Medicine & Biology
Another common scenario is ultrasound of the adult hip for ‘trochanteric bursitis’. Multiple bursa compartments are present between and adjacent to the tendons and muscles near the greater trochanter, and thin slips of fluid in these spaces are common. Pathologically proven trochanteric bursitis is uncommon, and usually associated with pathology of the gluteal tendons. Pain at the greater trochanter is very common, especially in elderly people. ‘Trochanteric bursitis’ is best thought of as a regional pain syndrome with various causes. The dominant role for ultrasound in this context is guidance of injection of steroid and local anaesthetic. Ultrasound of soft tissue masses is common, and usually straightforward in well characterised lesions like ganglia and lipomas. Sometimes however, ultrasound is unable to provide a specific diagnosis. This should not be the end of things. Based on their ultrasound features, unknown lesions should be sorted into either ‘probably benign’ or ‘indeterminate/ possibly malignant’, and further follow up recommended, such as MRI or specialist assessment. Rotator cuff repair is an increasingly common procedure. It may be performed with an open or arthroscopic technique, which consists of reattachment of the torn tendon to the humeral head with suture anchors. Patients may present with residual or recurrent pain or dysfunction for which imaging is required. A repaired cuff tendon will probably never look completely normal on ultrasound. Heterogeneity, thinning, and small residual defects are common post repair, as are bursal fluid and bone surface irregularity. In general terms, if fibres can be followed to the suture anchors, then the repair is probably intact. Correlation of surgical technique and direct consultation with the surgeon may be required in difficult cases. Inflammatory arthritis Fred Joshua President, Australian Society for Ultrasound in Medicine (ASUM), Kogarah, NSW, Australia Inflammatory arthritis is a common problem that is often under recognised. This presentation will discuss the causes of inflammatory arthritis and what key features ultrasound imaging helps to identify that aids in diagnosis and management.
SESSION 1C: VASCULAR Angle-Independent Blood Volume Flow Jonathan M. Rubin University of Michigan Department of Radiology, University of Michigan Hospital, Ann Arbor, MI, USA Standard ultrasound Doppler can estimate volume flow. However, the estimate depends on major assumptions, which include flow that has to be perfectly symmetric around the centerline of the vessel, a perfectly round vessel cross-section, and the Doppler measurements must be angle corrected. These restrictions make volume flow estimates problematic especially in environments where these assumptions do not hold, such as transjugular intrahepatic portosystemic shunts (TIPS) and umbilical cords. With the advent of 3D/4D ultrasound imaging, all of the limitations of ultrasound volume flow measurements can be overcome, potentially producing volume flow estimates that are as easy to obtain as standard color flow Doppler images, i.e. in real time. The method depends on the something called Gauss’s theorem. This law states that volume flow is equal to the sum of all of the normal velocity vectors passing through any surface. Simply put, this sum, also known as the total flux, is just the sum of the local products of the velocity of the blood going perpendicularly through every individual element of a surface that cuts across a blood vessel This can be any continuous surface (often known as a C-surface or C-plane), it does not have to be a plane, and the
Volume 45, Number S1, 2019 method contains none of the assumptions required for standard volume flow measurement. Thus, this method is angle independent, flow profile independent, and vessel geometry independent. Hence, non-laminar flow profiles produced by the irregular TIPS stent walls or highly tortuous umbilical arteries and veins do not affect this method. We have tested this technique in simulations, phantoms, in in-vivo animal models, and human subjects. The method has proven to work well in all of these settings. In humans, linear regression of data from revised TIPS cases showed an inverse correlation between mean-normalized change in pre- and post-revision shunt volume flow and mean-normalized change in pre- and post-revision portosystemic pressure gradient (r2 = 0.71, Pvalue = 0.0044). Depth-corrected and weight normalized umbilical vein volume flow measurements in normal and pre-eclampsia subjects showed a statistically significant difference between groups (P = 0.035). Further, these measurements were highly reproducible in the mean estimate with an intra-subject relative standard error (RSE) of 12.1 § 5.9 % and an intra-measurement RSE of 5.6 § 1.9 %. This method is easy to perform, accurate, and reproducible. Using 2D ultrasound arrays, it can be in real-time. It could have a major impact on future flow analysis. Quantification of Blood Flow in 3D Ultrasound Vascular Applications J. Brian Fowlkes Departments of Radiology and Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA Vascular ultrasound has an increasing role to play in the evaluation of numerous conditions such as peripheral vascular disease (PVD). Ultrasound imaging (b-mode and elastography) has been used for evaluation of vascular walls such as for deep venous thrombus (DVT) but there is also a need for flow assessment. With the increasing incidence of PVD, particularly related to diabetes, objective measures of flow in the extremities is important in medical management of such conditions. Doppler ultrasound can provide measurements of flow but generally in the major vessels and often relying on relative metrics such as pulsatility index, resistive index, etc. Subjective assessments are made in combination with selective limb compression or other conditions that would affect flow such as a Valsalva maneuver. Methods are being developed for more quantitative flow such as microvascular flow, ultrasound-based particle image velocimetry, Doppler vector flow, and contrast enhanced ultrasound (CEUS) as well as global flow metrics such as volumetric flow. This presentation will review some of the technology advances being made in the quantification of blood flow as these relate to vascular ultrasound. Can sonographers Reliably Scan Perforator Veins? Rob McGregor,1 Rod J. McGregor,2 Angie Fearon,2 Rob Davidson2 1 USVASC Pty Ltd, Farrer, ACT, Australia, 2 University of Canberra, Faculty of Health, Canberra, ACT, Australia Introduction: Diagnostic Ultrasound (DU) plays an integral role in the assessment and mapping of Chronic Venous Insufficiency (CVI) (Neglen & Raju, 1992; Zygmunt, 2014) and in particular the assessment and documentation of perforator veins.(Eidson Iii & Bush, 2010). Also evident is a paucity of research around the reliability and validity of sonographer measurement, in particular for vascular ultrasound. The overall research aim is to develop a tool to measure reliability and validity between sonographers in the assessment of perforator veins. The outcome will be then to implement that tool within a group of experienced vascular sonographers.