Faculty Bibliography

Ultrasound-guided hookwire localization was initially introduced to facilitate the excision of nonpalpable breast lesions by guiding surgical exploration, thereby reducing operative time and morbidity. The same technique has since found utility in a range of other applications outside breast and can be useful within the musculoskeletal system. Despite this, there remains limited literature with respect to its technical aspects and practical utility. We describe our technique and a series of preoperative ultrasound-guided wire localizations in the musculoskeletal system to assist surgical excision of 4 soft tissue masses.

Adult T cell leukemia/lymphoma (ATLL) is a mature T cell neoplasm caused by the human oncogenic retrovirus human T lymphotropic virus type-1 (HTLV-1). While several musculoskeletal manifestations have been described in ATLL, skeletal muscle involvement is unusual, with only four cases reported in the English-language literature. We present a rare case of ATLL manifesting as an intra-muscular calf mass in a 58-year-old man who immigrated to the USA from West Africa. While skeletal muscle involvement by lymphoma is uncommon, it remains important to consider within the differential diagnosis when there are suggestive imaging findings because it entails important technical biopsy considerations as well as treatment implications. This case report also raises awareness of ATLL presenting outside of typical HTLV-1 endemic areas, related to current population migration patterns. ATLL should therefore be considered in patients with appropriate risk factors.

OBJECTIVE:The purpose of this study was to determine whether SWE can detect biomechanical changes in the supraspinatus muscle that occur with increasing supraspinatus tendon abnormality prior to morphologic gray-scale changes. MATERIALS AND METHODS/METHODS:An IRB approved, HIPAA compliant retrospective study of shoulder ultrasounds from 2013-2018 was performed. The cohort consisted of 88 patients (mean age 55 ± 15 years old) with 110 ultrasounds. Images were acquired in longitudinal orientation to the supraspinatus muscle with shear wave velocity (SWV) point quantification. The tendon and muscle were graded in order of increasing tendinosis/tear (1-4 scale) and increasing fatty infiltration (0-3 scale). Mixed model analysis of variance, analysis of covariance, and Spearman rank correlation were used for statistical analysis. RESULTS:There was no statistically significant age or sex dependence for supraspinatus muscle SWV (p = 0.314, 0.118, respectively). There was no significant correlation between muscle SWV and muscle or tendon grade (p = 0.317, 0.691, respectively). In patients with morphologically normal muscle on gray-scale ultrasound, there were significant differences in muscle SWV when comparing tendon grade 3 with grades 1, 2, and 4 (p = 0.018, 0.025, 0.014, respectively), even when adjusting for gender and age (p = 0.044, 0.028, 0.018, respectively). Pairwise comparison of tendon grades other than those mentioned did not achieve statistical significance (p > 0.05). CONCLUSION/CONCLUSIONS:SWE can detect biomechanical differences within the supraspinatus muscle that are not morphologically evident on gray-scale ultrasound. Specifically, supraspinatus tendon partial tears with moderate to severe tendinosis may correspond to biomechanically distinct muscle properties compared to both lower grades of tendon abnormality and full-thickness tears.

RATIONALE AND OBJECTIVES/OBJECTIVE:The medial plantar proper digital nerve, also called Joplin's nerve, arises from the medial plantar nerve, courses along the medial hallux metatarsophalangeal joint, and can be a source of neuropathic pain due to various etiologies, following acute injury including bunion surgery and repetitive microtrauma. We describe our clinical experience with diagnostic ultrasound assessment of Joplin's neuropathy and technique for ultrasound-guided therapeutic intervention including both injection and cryoablation over a 6-year period. MATERIALS AND METHODS/METHODS:Retrospective review of all diagnostic studies performed for Joplin's neuropathy and therapeutic Joplin's nerve ultrasound-guided injections and cryoablations between 2012 and 2018 was performed. Indications for therapeutic injection and cryoablation, were recorded. Studies were assessed for sonographic abnormalities related to the nerve and perineural soft tissues. Post-treatment outcomes including immediate pain scores, clinical follow-up, and periprocedural complications were documented. RESULTS:Twenty-four ultrasound-guided procedures were performed, including 15 perineural injections and nine cryoablations. With respect to sonographic abnormalities, nerve thickening (33%) and perineural hypoechoic scar tissue (27%) were the most common findings. The mean pain severity score prior to the therapeutic injection was 6.4/10 (range 4-10) and 0.25/10 (range 0-2) following the procedure; mean follow-up was 26.2 months (range 3-63 months). All of the cryoablation patients experienced sustained pain relief with a mean length follow-up of 3.75 months (range 0.2-10 months). CONCLUSION/CONCLUSIONS:Therapeutic injection of Joplin's nerve is a safe and easily performed procedure under ultrasound guidance, with high rates of immediate symptom improvement. For those experiencing a relapse or recurrent symptoms, cryoablation offers an effective secondary potential treatment option.

Objective: To describe the role of vascularity in assessing bone tendon healing and describe the application of ultrasound contrast agents in quantitative and visual assessment of the vascular following repair with attention to the rotator cuff. Rotator cuff tears are common, having been described in up to 20.7% of the general population and accounting for approximately 75,000 operations in the United States per year. The reported prevalence of failure of rotator cuff repairs has varied in the literature, ranging from 19-94%. Various factors are thought to account for poor healing of the repair, including intrinsic tendon degeneration, fatty infiltration of the muscle and tendon, muscle atrophy, poor bone quality, and weak tendon-to-bone fixation. Experimental studies have shown that bone-tendon healing begins with the formation of fibrovascular scar tissue between the tendon and bone, followed by gradual bone ingrowth into this fibrous interface extending into the native tendon. Tendon repair therefore involves multiple phases: an inflammatory phase, reparative phase and finally remodeling phase. These phases are linked to a variety of growth factors that appear most active in a temporal sequence. Consequently, an area of active investigation is to determine methods to augment bone-tendon and tendon-tendon healing using endogenous growth factors, such as those derived from platelet rich aggregates to promote bone tendon healing. The role of imaging in this scenario is to provide a non-invasive means to potentially determine various phases of healing and to assess the outcomes of either primary repair or interventions meant to augment healing. In the current talk, we briefly describe the sequence of events associated with tendon degeneration, tearing and subsequent bone-tendon healing, following repair. In particular we review the role of contrast enhanced ultrasound in depicting the temporal changes in vascularity following rotator cuff repair.
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Objective: At the conclusion of this activity, participants will understand the basic principles of MR-US fusion and potential applications to the musculoskeletal system. Development of a simple phantom for training will be described. Examples of injections performed to date will be shown to illustrate potential applications and challenges in obtaining adequate registration. Ultrasound guided injections have become increasing utilized over the past several years. In many instances, these derive from direct referrals following MR or CT. Correspondence of abnormalities seen on cross-sectional imaging, however, may not always be readily evident on ultrasound, Examples would include deep seated abnormalities which are not amenable to high frequency transducers or low contrast lesions on gray-scaleultrasound that are highly conspicuous on MR. MR-US co-registration provides a method to visualize the relevant soft tissue anatomy with greater confidence, while allowing for differences in the image acquisition plane. MR-US fusion has largely been applied to abdominal applications, with relatively few musculoskeletal applications reported to date. The basic requirements of registration include having a representative high-resolution MR (or CT) data set, a method to track the transducer orientation in space (usually through a "Flock of Birds technique"), and the selection of internal fiduciary points common to both data sets (minimally 3 points at different locations). Based on phantom data, accuracies of approximately 5mm or less can be achieved. A brief survey of the technical aspects of co-registration will be discussed, followed by the typical sequence employed to achieve registration with musculoskeletal applications in mind. A series of clinical examples will be presented from therapeutic injections, aspirations or biopsies in the musculoskeletlal system performed at our institution. Use of a relatively simply constructed gelatin phantom will also be described to serve as a potential learning tool to improve individual throughput in the early phase of performing these procedures. The challenges, limitations and potential benefits of using real-time co-registration techniques will be discussed.
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Objective: To describe our experience performing cryoablative procedures for patients with painful peripheral nerve lesions, excluding patients with chronic regional pain syndrome. The real-time nature of ultrasound makes it ideally suited to provide guidance for a variety of musculoskeletal interventional procedures involving peripheral nerves. Continuous observation of the needle ensures proper placement and allows continuous monitoring when performing localized ablative therapy and therefore, more accurate positioning of a cryoprobe, use of smaller needles, as well as access to small structures. In the current talk, we describe our experience performing cryoablative procedures for a variety of painful peripheral nerve lesions. In our experience, patients undergoing cryoneurolysis have reported varying degrees of long-term pain relief and improvement in function; no serious complications have yet been identified. Ultrasound guided cryoneurolysis can provide a useful, safe alternative to other ablative techniques to achieve long-term analgesia. In as much as there is only limited patient outcome data available to date, we present descriptive information as to our current technique with limited patient follow-up. For purposes of the current discussion, we will not include examples of patients with chronic regional pain syndrome as they form a complex group of patients not easily addressed through simple targeted ablative techniques.
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Objectives: To describe our experience applying shear wave elastography to the musculoskeletal system, as well as some potential sources of artifact when applying this new technology. Disease states in the musculoskeletal system often manifest as altered tissue morphology evident on conventional gray-scale ultrasound imaging. These states also display other changes, such as altered tissue vascularity and mechanical properties. An example would be the tendon softening associated with tendinosis. US elastography provides a measure of local soft-tissue stiffness by means of mechanical stimulation. Presently, the two most common forms of US elastography measure tissue stiffness and strain by recording (a) how tissues respond to external compression obtained by applying manual pressure (Quasi-static or compression based on response to acoustic radiation force generated by the ultrasound transducer, the latter referred to as Shear-Wave Elastography (SWE). SWE employs a focused acoustic beam generated by the US transducer to compress the underlying tissue, thereby inducing a local shear wave. The speed of that wave, also known as the shear- wave velocity (SWV), is then measured as it propagates through the tissue and displayed as a parametric image or through selective region-of-interest (ROI) analysis, measured in meters per second. SWV provides a quantitative metric of tissue stiffness because it directly relates to the local shear elastic modulus, such that the stiffer the tissue, the greater the SWV. Consequently, some vendors directly display shear wave data as elastic modulus in kilopascals (KPS). In the current discussion, we briefly review some basic principles of shear wave imaging, review some of the common musculoskeletal applications, to date, and describe our experience using SWE in the musculoskeletal system with attention to skeletal muscle and tendons. We review some potential artifacts that the sonographer should be aware of in applying this new technology to tendon and muscle imaging.
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Our aim was to test the effectiveness of ultrasound-guided intra-articular (IA) injection into the knee joint of rodents by an inexperienced operator compared with standard landmark-guided IA injections by a trained injector. Fifty landmark-guided and 46 ultrasound-guided IA injections in 49 rats were analyzed. Animal positioning and injection protocol were designed for use with the ultrasound system. Injection delivery was verified with a secondary imaging modality. We compared the success of IA injections by method (landmark and ultrasound-guided), adjusting for all other confounding factors (age, weight, experience, laterality and presence of surgery). Ultrasound-guided injections had higher success rates overall (89% vs. 58%) and helped to reduce the number of failed attempts per injection. None of the cofounding factors influenced the success of injection. In conclusion, we found higher accuracy for ultrasound-guided IA injection delivery than the traditional landmark-based injection method and also the technical feasibility for untrained personnel.