Diagnostic Accuracy of Four Levels of Manual Compression Applied in Supersonic Shear Wave Elastography of the Breast.

PURPOSE: To investigate the diagnostic accuracy of applying four levels of manual pressure in Shear Wave Elastography (SWE) of the breast and to assess inter-rater reliability. MATERIALS AND METHODS: Single-center prospective preliminary study including patients receiving ultrasound examination of breast lesions as part of routine clinical practice. SWE was performed on 60 breast masses (26 benign and 34 malignant) in 54 patients by a breast fellowship trained radiologist. Stiffness values were compared between benign and malignant masses at four levels of manual compression: none, mild, moderate, and marked. Accuracy of SWE was assessed using receiving operating characteristics analysis at each level. In 18 patients, a second radiologist repeated the SWE acquisitions to evaluate reproducibility. Reproducibility was assessed using intraclass correlation coefficient. RESULTS: Without compression, we observed no significant difference in stiffness (p > 0.99) between benign and malignant lesions, and SWE demonstrated low accuracy (area under the curve = 0.64). Stiffness was higher in malignant lesions at all levels of compression (p < 0.001). SWE demonstrated good accuracy at all three levels of compression (from area under the curve = 0.71 to 0.84 across Emax and Emean), with high interobserver agreement. CONCLUSION: This preliminary study suggests that not using compression during SWE for breast lesion characterization offers suboptimal results. On the contrary, application of compression yields high diagnostic performance with good interobserver agreement and, as such, should be included in routine clinical practice.

Pre-surgical CT-assessment of neurogenic myositis ossificans of the hip and risk factors of recurrence: a series of 101 consecutive patients.

BACKGROUND: Neurogenic Myositis Ossificans (NMO) is a rare disabling pathology characterized by peri-articular heterotopic ossifications following severe peripheral or central nervous system injuries. It results in ankylosis and vessels or nerves compressions. Our study aimed to describe the pre-operative findings of patients with NMO of the hip using biphasic computerized tomography (CT). METHODS: Between 2006 and 2012, we retrospectively analyzed 101 consecutive patients with hip NMO. We analyzed all CTs and surgical reports following a standardized grid depicting the osteoma and its relations with joint capsule, vessels and nerves and bone mineralization. We studied surgical complications and recurrence during follow-up. Chi2-test and Fischer's test were performed to compare qualitative values with respectively normal and non-normal distribution. Quantitative values were analyzed with a one factor analysis of variance (ANOVA) test. Agreement between pre-surgical CT and surgical observations was evaluated with Cohen's kappa test. RESULTS: Correlation between pre-operative CT and surgical findings was excellent regarding relationships with vessels (0,82) and was good concerning relationships with sciatic nerves (0.62) and with joint capsule (0.68). Close contact or disruption of joint capsule (p = 0.005), joint space narrowing (p = 0.007) and bone demineralization (p < 0.001) were correlated with NMO recurrence. CONCLUSIONS: Biphasic enhanced-CT allows pre-operative assessment of NMO with good correlation to surgical observations and helps prevent surgical complications.

Sciatic nerve compression by neurogenic heterotopic ossification: use of CT to determine surgical indications.

OBJECTIVE: To describe the characteristics of neurogenic heterotopic ossification (NHO) based on clinical tests, electroneuromyography (ENMG) and CT in a database of patients with lesions of the central nervous system who required sciatic nerve neurolysis along with posterior hip NHO resection, and to determine the respective roles of ENMG and CT in the management of posterior hip NHOs in patients who are unable to communicate or express pain. METHODS: The consistency of the ENMG results with clinical findings, CT results and macroscopic signs of lesions was retrospectively assessed after sciatic nerve neurolysis and ablation of 55 posterior hip NHOs. RESULTS: Sciatic nerve neurolysis was necessary in 55 cases (47.4%; 55 out of 116). CT showed contact of the NHO with the nerve in all cases: 5 in contact with no deflection, 3 in contact with deflection, 21 moulded into a gutter and 26 entrapped in the NHO. There were clinical signs of sciatic nerve lesion in 21.8% of cases (12 out of 55). ENMG showed signs of sciatic nerve lesions in only 55.6% (10 out of 18), only 4 of whom presented with clinical signs of a nerve lesion. No significant relationship was found between clinical symptoms and ENMG findings of sciatic nerve compression (n = 13, p = 0.77). CONCLUSION: Nerve compression by NHO is likely an underdiagnosed condition, particularly in patients who are unable to communicate. Diagnosis of sciatic compression by NHO should be based on regular clinical examinations and CT. ENMG is not sufficiently sensitive to be used alone for surgical decision-making.