Dynamic ultrasound of the subacromial-subdeltoid bursa in patients with shoulder impingement: a comparison with normal volunteers.

OBJECTIVE: The purpose of the study was to determine if the thickness of the subacromial-subdeltoid (SASD) bursa during dynamic ultrasound and on static views differs between patients with shoulder impingement syndrome and healthy volunteers. MATERIALS AND METHODS: Twenty-two patients with a clinical diagnosis of shoulder impingement syndrome and 23 healthy volunteers were recruited. A subset of patients showing an immediate symptom response following intrabursal injection was identified as "injection responders". Ultrasound of the shoulder was performed on all participants using three standard static views and two dynamic views (before and after arm abduction). The thickness of both the intrabursal fluid and the superficial peribursal fat was measured on all views. The bursal thickness measurements in the two groups were compared using a t test for significance. RESULTS: The mean increase in SASD bursal fluid thickness following arm abduction was not statistically different among all patients (0.39 ± 0.41 mm) and controls (0.35 ± 0.32 mm), p = 0.72. The same was true comparing injection responders (0.46 ± 0.49 mm) with controls, p = 0.41. On static views, greater bursal fluid thickness was found in patients (1.01 ± 0.48 mm) compared with controls (0.67 ± 0.32 mm) when using the short axis view of the supraspinatus, p = 0.006. No statistically significant difference was found between injection responders and controls when measuring peribursal fat thickness on any view. CONCLUSIONS: Gathering of the SASD bursa demonstrated during dynamic ultrasound does not necessarily indicate painful impingement of the bursa as it is found to a similar degree in patients with a clinical diagnosis of impingement and healthy volunteers.

Indeterminate soft-tissue tumors of the hand and wrist: a review based on a clinical series of 39 cases.

Soft-tissue masses located at the hand and wrist are a frequent clinical presentation. The majority of these are ganglia, which have characteristic imaging features. Other common masses in which a diagnosis is suggested by imaging include hemangiomas, lipomas, and focal synovitis. The remainder are rare although a diagnosis may be attempted by considering the patients' age and the location. We reviewed 39 soft-tissue masses at the hand and wrist referred to our institution between September 1998 and January 2006 that had indeterminate imaging features. The majority were benign neoplastic lesions with the most common being a giant cell tumor of the tendon sheath, followed by angioleiomyoma, peripheral nerve sheath tumor, fibromatosis, fibroma of tendon sheath, and solitary fibrous tumor. These lesions tend to occur in young adults at the metacarpal level. However, there are no imaging features that can reliably differentiate between benign and malignant tumors.

Imaging in covert ectopic ACTH secretion: a CT pictorial review.

The syndrome of ectopic adrenocorticotrophin secretion (EAS) is rare and is due to excess adrenocorticotrophin (ACTH) production from a nonpituitary tumour. These tumours can be covert, where the tumours are not readily apparent, and very small making them challenging to image. It is clinically and biochemically difficult to distinguish between covert EAS and Cushing's disease. The first-line investigation in locating the source of ACTH production is computed tomography (CT). The aim of this pictorial review is to illustrate the likely covert sites and related imaging findings. We review the CT appearances of tumours resulting in covert EAS and the associated literature. The most common tumours were bronchial carcinoid tumours, which appear as small, well-defined, round or ovoid pulmonary lesions. Rarer causes included thymic carcinoids, gastrointestinal carcinoids and pancreatic neuroendocrine tumours. Awareness of the imaging characteristics will aid identification of the source of ACTH production and allow potentially curative surgical resection.

Accessory muscles: anatomy, symptoms, and radiologic evaluation.

A wide array of supernumerary and accessory musculature has been described in the anatomic, surgical, and radiology literature. In the vast majority of cases, accessory muscles are asymptomatic and represent incidental findings at surgery or imaging. In some cases, however, accessory muscles may produce clinical symptoms. These symptoms may be related to a palpable swelling or may be the result of mass effect on neurovascular structures, typically in fibro-osseous tunnels. In cases in which an obvious cause for such symptoms is not evident, recognition and careful evaluation of accessory muscles may aid in diagnosis and treatment.