Clinical Trials

The purpose of this study is to observe newly-graduated CRNAs and their skills level in placing arterial lines using palpation vs. ultrasound guidance method.

The purpose of this study is to address a knowledge gap. Early diagnosis of nerve root avulsion injuries following brachial plexus trauma remain a barrier to the early treatment of these complex injuries.  Traditionally, an observation period of 6 months following brachial plexus injuries has been utilized to allow for reinnervation.  Reinnervation is not possible in the setting of nerve root avulsion from the spinal cord and waiting for reinnervation in this setting unnecessarily delays treatment and potentially compromises outcome.  Having the ability to provide a real time evaluation of nerve root integrity would obviate the need of other more expensive and complex advanced imaging such as CT/myelography, currently considered the good standard.

Aim 1 of this project will be entirely cadaveric and, thus, classified as not-human-subjects research by the Mayo Clinic IRB. Eight fresh-frozen cadaveric lower extremities (no history of knee trauma; < 50 years of age) will be acquired from a vendor that has provided >50 specimens with similar criteria in the past three years.5 Specimens will be thawed 24 hours prior to testing. 3D musculoskeletal (MSK) US images of the ACL in the intact knee will be acquired with an Aixplorer Mach 30 (SuperSonic Imagine, Bothell, WA). Literature described imaging techniques from both the anterior and posterior aspect of the knee will be used. SWE stiffness of the ACL will be calculated from the obtained images for cross-correlation against mechanical failure properties. Once images have been collected, each specimen will be resected such that the bone-ACL-bone complex remains intact. These complexes will be individually secured into custom mechanical fixtures and placed into a uniaxial hydraulic tensioner (MTS Systems, Eden Prairie, MN). Each structure will be exposed to 50 stress/relaxation cycles that vary ligament tension from 0-3% to remove viscoelastic effects. Specimens will then be tensioned at 20%/sec until failure is achieved. During tensioning, the hydraulic tensioner will measure displacement and a uniaxial load cell mounted to the tensioner will record linear force enacted on the tissue. ACL strain will be calculated as the linear displacement divided by the neutral ligament length (longest distance between ACL origin and insertion where the load cell registers 0 N force). Linear regression models will determine the significance of association between failure properties (ultimate strain, stress, and tensile strength) and US stiffness.

            For Aim 2, 40 total lower extremities will be recruited for 3D US imaging of the ACL at their pre-surgical clinical visit. This will include the injured limb from 20 pre-surgical patients with an MRI-confirmed ACL rupture and 20 healthy control limbs with no documented history of injury or scheduled surgery. Subjects recruited for the injured limb cohort may be dual-recruited as controls so long as their contralateral limb satisfies the inclusion criteria. US images will be acquired from both the anterior and posterior aspect of each knee. Injured versus control status will be documented by the collecting research team member. These images will be assessed and descriptively categorized by a separate, blinded, experienced rater for tear presence, location, severity, and type. For injured limbs, the clinical MRI for each subject will be acquired and similarly categorized. For healthy limbs, a research MRI will be scheduled and similarly categorized. Chi-Square test of independence will be used to assess statistical correlation between the US and MRI image classification. Receiver operator curves will be used to assess sensitivity and specificity of US and MRI diagnoses of ACL injuries against known clinical conditions.

The purpose of this is observational study of lung ultrasound in adults (> 18 years) with congenital heart disease (N=25) undergoing cardiopulmonary exercise testing (CPET) or stress echocardiogram (SE) designed for the purpose of describing the technical feasibility of lung ultrasound for classifying heart failure in ACHD patients.

The purpose of this study is to utilize direct visualization of proximal arterial occlusion via point-of-care ultrasonography (POCUS), with an eventual goal of developing a simple, inexpensive model for both assessment and instruction of hemorrhage control.

The purpose of this study is to determine if lung ultrasound surface wave elastography (LUSWE) can accurately detect changes in lung elasticity (compliance) caused by the presence of extravascular lung water  (pulmonary edema).

The purpose of this study is to evaluate and compare the effectiveness of active screening for SHD in asymptomatic outpatients referred for an ECG, using a combination of AI-ECG and FOCUS. Invites will be sent and participants enrolled electronically.

The purpose of this study is the evaluation of ultrasound imaging to detect a neurovascular pedicle crossing the sciatic nerve in the posterior thigh of healthy adults and patients with spastic hamstring muscles undergoing neurectomy. Determine the feasibility of ultrasound detection of the neurovascular pedicle in the hamstring region by measuring the proportion of subjects (healthy adults and preoperative patients) in whom the pedicle is visualized on ultrasound (present/absent) compared to intraoperative.

The purpose of this study is to prospectively validate a new Artificial Intelligence (AI)-based model developed by our team to analyze TVUS images for early EC detection.  

The purpose of this study is to quantify medial meniscal extrusion with and without a medial knee unloader brace using ultrasonography in patients with isolated medial knee pain.