Evaluation of the rupture of silicone breast implants by mammography, ultrasonography and magnetic resonance imaging in asymptomatic patients: correlation with surgical findings.

CONTEXT: Different imaging methods can identify the integrity of breast implants and also the extent of possible silicone leakage. Mammography, ultrasonography and magnetic resonance imaging are often used to evaluate the integrity of breast implants, usually in patients that are symptomatic for rupture. A group of clinically asymptomatic patients was taken as a sample. These patients wanted to remove or change their breast implants for psychological or cosmetic reasons.

OBJECTIVE: The purpose of this study was to compare the efficacy of mammography, sonography and magnetic resonance imaging in the detection of breast implant rupture in an asymptomatic population.

TYPE OF STUDY: Prospective study.

SETTING: Department of Diagnostic Imaging, Universidade de São Paulo, São Paulo, Brazil.

METHODS: The participants were 44 asymptomatic patients who subsequently had implants surgically removed. Eighty-three implants were evaluated by both film-screen mammography and high-resolution sonography and 77 implants were evaluated by magnetic resonance imaging. The sensitivity and specificity of mammography, ultrasonography and magnetic resonance imaging were assessed using predetermined diagnostic criteria for implant rupture. All radiological signs were discussed and false positives and false negatives were retrospectively evaluated to identify the pitfalls in the investigations.

RESULTS: The respective sensitivity and specificity of mammography were 20% and 89%; sonography, 30% and 81%; and magnetic resonance imaging, 64% and 77%. The differences between patients with breast implants for cosmetic and oncological reasons were discussed.

CONCLUSIONS: Our experience suggests that magnetic resonance imaging seems to be the best imaging method on its own for the evaluation of rupturing among asymptomatic patients.