IS Case 238: Extracapsular rupture of silicone implant - mammogram/ultrasound correlation

Nate Johnson, MD

Imaging Sciences URMC 2008
Publication Date: 2009-05-26

History

Patient is a 54-year-old female status post-bilateral silicone breast implant presenting with complaint of palpable lump in right breast.

Diagnosis

Extracapsular rupture of silicone implant - mammogram/ultrasound correlation

Discussion

In patients status post-breast implantation, rupture is a common complication. Rupture is subdivided into the intracapsular and extracapsular types based on whether the silicone has escaped the fibrous capsule surrounding the implant.

Extracapsular silicone can appear as a mass on mammography with the same density as the implant. Or, as in our patient, a focal bulge which does not appear as a discrete mass outside the implant.

Ultrasound of intracapsular rupture may demonstrate a collapsed shell which manifests itself as a "stepladder" appearance. This is due to visualization of multiple layers of the collapsed shell. Abnormal echoes may also be identified within the lumen of the implant and shell discontinuity may be visualized. The MRI equivalent to this is the "linguine sign."

In cases of extracapsular rupture the silicone has escaped the fibrous shell that has developed around the breast implant. Free silicone may then be present within the soft tissues of the breast which causes scattering of the ultrasound beam in the region. This is classically described as a "snowstorm" appearance and is seen in our patient. MRI may demonstrate extracapsular silicone in cases of extracapsular rupture.

References

  1. Forsberg F, Conant EF, Piccoli CW, Rawool NM, Moore JH Jr. Intra-operative and three-dimensional ultrasound guided explantation of silicone breast implants. IEEE Ultrasonics Symposium 1994, 3:1673-1676.
  2. Marques A, Brenda E, Amarante MTJ, Dominguez Pereira M, Castro M, Haddad A. Findings in the removal of silicone gel breast implants: a correlation between time of implantation and rupture. Eur J Plast Surg (1997) 20(1):15-18.
  3. Berg WA, Birdwell RL, Gombos E, et al. Diagnostic Imaging: Breast. Amirsys, 2006.

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