Faculty Bibliography

Purpose: Ultrasound is increasingly utilized as the first-line diagnostic evaluation of superficial soft tissue masses. With growing health care costs, there is increasing pressure to develop cost-effective methods to triage patients with palpable masses. Deep convolutional neural networks (CNNs) have demonstrated the ability to classify images with good accuracy. We hypothesize that using a limited dataset, a CNN can be trained to classify benign versus malignant soft tissue masses seen on ultrasound.
Material(s) and Method(s): Ultrasound exams from 227 patients were selected with up to two pairs of gray scale and Doppler images extracted per patient. Pairs of gray scale and Doppler images were concatenated to create a single image for a total of 344 combined images. Images from 49 patients (96 images) were withheld for a pathology enriched test set (56 benign and 40 malignant). The remaining 248 images were used to train a CNN using an 80/20 training-validation split with five-fold crossvalidation. The model was trained on Keras using a pretrained VGG-16 architecture on a Nvidia GTX 1070 GPU. The withheld test set was used for a reader study which consists of two experienced musculoskeletal radiologists to assess the performance of the model.
Result(s): The CNN achieved an average accuracy of 0.87+/-0.07 on fivefold cross validation. The best performing model in the five folds was selected for comparison against two musculoskeletal radiologists on the pathology enriched test data set. The model achieved an accuracy 0.73 on the test data set and an AUC of 0.78 which was comparable to the performance of the two musculoskeletal radiologists (0.76 and 0.65 accuracy).
Conclusion(s): Using a relatively small data set, a CNN can be trained to differentiate between benign and malignant soft tissue masses seen on ultrasound with its performance approaching that of two experienced musculoskeletal radiologists

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.

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.

Lower extremity superficial venous aneurysms are occasionally encountered by clinicians and are almost always located above the knee. Very few cases of aneurysm of the medial marginal vein in the most distal part, near the origin of the great saphenous vein, have been reported. We present a case of partially thrombosed aneurysm of the medial marginal vein, and briefly review the imaging characteristics and treatment options of this entity. Being aware of the existence of superficial venous aneurysms may help clinicians in their differential diagnosis of foot masses and choice of appropriate treatment.

Scapulothoracic pain is a common ailment, but the underlying cause can be difficult to diagnose in a timely manner, and treatment options are limited. We retrospectively review our experience using ultrasound-guided therapeutic scapulothoracic interval steroid injections to treat scapulothoracic pain and review correlative magnetic resonance imaging findings over a 5-year period. Although a variety of structural causes are known to cause scapulothoracic pain, in our experience, most cases lack correlative imaging findings. Ultrasound-guided scapulothoracic interval injections provide a safe, easily performed diagnostic and therapeutic tool for treating patients with periscapular pain, providing at least short-term symptom relief.

Piriformis syndrome is a common cause of lumbar, gluteal, and thigh pain, frequently associated with sciatic nerve symptoms. Potential etiologies include muscle injury or chronic muscle stretching associated with gait disturbances. There is a common pathological end pathway involving hypertrophy, spasm, contracture, inflammation, and scarring of the piriformis muscle, leading to impingement of the sciatic nerve. Ultrasound-guided piriformis injections are frequently used in the treatment of these pain syndromes, with most of the published literature describing injection of the muscle. We describe a safe, effective ultrasound-guided injection technique for the treatment of piriformis syndrome using targeted sciatic perineural hydrodissection followed by therapeutic corticosteroid injection.

Purpose: To better understand alterations in repaired supraspinatus tendons using a multimodality approach including MRI, assessment of tendon vascularity by power Doppler (PD), and tendon mechanical properties using shear wave elastography (SWE). To investigate whether SWE and PD can provide quantitative assessment of tendon healing following rotator cuff repair.
Material(s) and Method(s): This HIPAA compliant prospective study was approved by the institutional review board with informed consent. Between 9/2013 and 6/2016, twelve patients (7 males, 5 females; mean age 61 years) with unilateral full-thickness supraspinatus tendon tears underwent MRI and ultrasound pre-operatively, 3-months and 6-months post-surgery. The supraspinatus tendon MRI signal intensity, PD and SWE properties were measured. Repaired and asymptomatic shoulders were compared over time within and between modalities.
Result(s): No significant association was seen between mean SWE and MRI signal intensity (non-insertional portion -0.25, p=0.467, insertional portion -0.18, p=0.593), or between PD and MRI signal intensity (non-insertional portion -0.19, p=0.599, insertional portion 0.22, p=0.533) within the supraspinatus tendon. MRI signal intensity and PD within the supraspinatus tendon, both increased and then decreased postoperatively. Shear wave velocities increased throughout the postoperative period in the tendon footprint, while increasing and then decreasing in the distal tendon.
Conclusion(s): MRI and ultrasound parameters did not achieve statistically significant correlation; however, their respective trend behavior suggests that a temporal relationship exists between modali ties. We postul a te that a more detai l ed multiparametric imaging approach and/or comparison with a more selective MR measure, such as T2* values, may be required to evaluate rotator cuff repair

OBJECTIVE:The purpose of this study was to describe clinical experience with ultrasound-guided therapeutic procedures and associated pathologic conditions involving the peripheral nerves of the upper extremity over 5 years at a large academic institution. MATERIALS AND METHODS/METHODS:A retrospective database search of procedure codes was performed for all ultrasound-guided upper extremity peripheral nerve procedures between 2012 and 2017. Retrospective review of the electronic medical record for patient demographics, indications, interval follow-up pain relief, and complications was undertaken. Retrospective review of ultrasound and other correlative imaging findings was performed to assess for neural and perineural abnormalities. RESULTS:In total, 242 procedures performed on a cohort of 183 patients (53% women, 47% men; mean age, 53 years; range, 15-97 years) were reviewed. Nine patients underwent multifocal injections in a single encounter, and 39 underwent repeat injections of previously documented symptom generators. Perineural injections included ulnar (n = 109), median (n = 81), posterior interosseous-deep radial (n = 39), sensory branch of the radial (n = 7), anterior interosseous (n = 2), axillary (n = 2), suprascapular (n = 1), and digital (n = 1) nerves. Structural or dynamic abnormality seen either during the procedure or at preprocedural imaging included loss of normal morphologic features (n = 148), nerve subluxation (n = 8), ganglion cyst (n = 4), and neuroma (n = 7). Forty-four patients reported immediate pain relief after the procedure. Of the 89 patients with documented clinical follow-up, 52 reported a period of symptom relief (mean, 125 days), and six reported complete resolution of symptoms. Subsequent surgical procedures were performed on 32 patients, a combination of those who did (n = 12) and did not (n = 20) experience a period of symptom relief from the perineural injection. There were no complications with regard to the site or distribution of perineural injections. Three episodes of vasovagal reaction were reported. CONCLUSION/CONCLUSIONS:Ultrasound-guided percutaneous interventions for upper extremity neural abnormalities can be safely performed for a variety of indications. Real-time ultra-sound evaluation during the procedure allows assessment for neural and perineural abnormalities and tailoring of the procedure to potentially symptomatic structural abnormalities.