MR Imaging of Breast Implants
MR Imaging of Breast Implants
Similarly, there are several indications of definitive implant rupture:
The most specific MRI finding for intracapsular silicone implant rupture is the "linguine sign" and was first described by Gorczyca, et al, in 1992. In a study by Vestito, et al, the "linguine sign" was the single most frequently identified finding with intracapsular rupture. They reported a sensitivity of 96%, specificity of 77% and diagnostic accuracy of 90%. They also reported that neither the "noose sign" nor the "droplet sign" were statistically significant findings for rupture, unless combined with other signs indicative of rupture. The "subcapsular line sign" is a similar finding that likely represents an earlier variant of the "linguine sign."
The most common reason for having a false-positive MRI indicating implant rupture occurs when a single sign of implant rupture is used to make the diagnosis, including the most specific finding, "linguine sign."
(Enlarge Image)
Figure 2.
Depictions of definitive implant rupture. (A) A 61-year-old woman with palpable left breast mass and 20 year-old silicone implants. She underwent MRI after equivocal findings for rupture on mammogram and sonogram. Axial silicone selective sequence demonstrates a radial fold in the medial aspect of the left breast implant but increased signal intensity (orange arrow) is present between the two leaves of the elastomer shell, consistent with extraluminal silicone, an intracapsular rupture. Additionally, there is increased signal intensity in the extracapsular anterolateral aspect of the left breast (green arrow), adjacent to the implant, which corresponded with her palpable complaint and is consistent with extracapsular rupture. A subcapsular line sign is noted at the posteromedial right breast implant (red arrow). (B) A 50-year-old woman with 13-year-old silicone implants being evaluated for possible rupture. Silicone sensitive sequence demonstrates multiple findings indicative of intracapsular rupture: Linguine sign – right breast (orange arrow), water droplet sign – dark round spots in the right breast implant (blue arrow), subcapsular line sign – anterior left breast implant (red arrow), keyhole/noose sign – medial and lateral left breast implant (green arrow). (C,D). Increased signal intensity within the right breast implant on the axial STIR sequence and axial T2 is consistent with water droplets (blue arrows) within the right breast implant. (E) A 54-year-old woman with MRI for implant rupture evaluation. Silicone-selective sequence demonstrates intracapsular and extracapsular rupture with extracapsular silicone (red arrow) and "salad oil" sign (orange arrow) with high-signal intensity silicone mixing with low-signal intensity body fluids in the medial aspect of the left breast implant. (F) A 62-year-old woman with contour abnormalities of breast implants on screening mammogram. The left breast axial STIR images demonstrate intracapsular and extracapsular rupture with hypointensity of the calcified fibrous capsule (orange arrow) and increased signal intensity from silicone within the capsule (green arrow) and the extracapsular soft tissues (red arrows) of the medial and lateral breast, confirmed on PASTA-SI sequence. The left breast implant also demonstrates subcapsular line sign, consistent with intracapsular rupture.
Signs of Definitive Implant Rupture (Figures 2A-E)
Similarly, there are several indications of definitive implant rupture:
Subcapsular lines. These are distinct hypointense lines (bordered by silicone signal intensity on both sides) running parallel to the fibrous capsule but are otherwise contiguous with the implant shell and represent intracapsular rupture.
Free silicone. This indicates violation or loss of integrity of the capsular shell with extravasation of silicone into the adjacent tissues.
Linguine sign. Multiple low signal intensity curvilinear lines are present floating within the silicone gel and represent collapse of the silicone elastomer implant shell. As the name implies, these have an appearance similar to linguine noodles.
Railroad track sign. Paired parallel subcapsular lines in the silicone gel.
The most specific MRI finding for intracapsular silicone implant rupture is the "linguine sign" and was first described by Gorczyca, et al, in 1992. In a study by Vestito, et al, the "linguine sign" was the single most frequently identified finding with intracapsular rupture. They reported a sensitivity of 96%, specificity of 77% and diagnostic accuracy of 90%. They also reported that neither the "noose sign" nor the "droplet sign" were statistically significant findings for rupture, unless combined with other signs indicative of rupture. The "subcapsular line sign" is a similar finding that likely represents an earlier variant of the "linguine sign."
The most common reason for having a false-positive MRI indicating implant rupture occurs when a single sign of implant rupture is used to make the diagnosis, including the most specific finding, "linguine sign."
(Enlarge Image)
Figure 2.
Depictions of definitive implant rupture. (A) A 61-year-old woman with palpable left breast mass and 20 year-old silicone implants. She underwent MRI after equivocal findings for rupture on mammogram and sonogram. Axial silicone selective sequence demonstrates a radial fold in the medial aspect of the left breast implant but increased signal intensity (orange arrow) is present between the two leaves of the elastomer shell, consistent with extraluminal silicone, an intracapsular rupture. Additionally, there is increased signal intensity in the extracapsular anterolateral aspect of the left breast (green arrow), adjacent to the implant, which corresponded with her palpable complaint and is consistent with extracapsular rupture. A subcapsular line sign is noted at the posteromedial right breast implant (red arrow). (B) A 50-year-old woman with 13-year-old silicone implants being evaluated for possible rupture. Silicone sensitive sequence demonstrates multiple findings indicative of intracapsular rupture: Linguine sign – right breast (orange arrow), water droplet sign – dark round spots in the right breast implant (blue arrow), subcapsular line sign – anterior left breast implant (red arrow), keyhole/noose sign – medial and lateral left breast implant (green arrow). (C,D). Increased signal intensity within the right breast implant on the axial STIR sequence and axial T2 is consistent with water droplets (blue arrows) within the right breast implant. (E) A 54-year-old woman with MRI for implant rupture evaluation. Silicone-selective sequence demonstrates intracapsular and extracapsular rupture with extracapsular silicone (red arrow) and "salad oil" sign (orange arrow) with high-signal intensity silicone mixing with low-signal intensity body fluids in the medial aspect of the left breast implant. (F) A 62-year-old woman with contour abnormalities of breast implants on screening mammogram. The left breast axial STIR images demonstrate intracapsular and extracapsular rupture with hypointensity of the calcified fibrous capsule (orange arrow) and increased signal intensity from silicone within the capsule (green arrow) and the extracapsular soft tissues (red arrows) of the medial and lateral breast, confirmed on PASTA-SI sequence. The left breast implant also demonstrates subcapsular line sign, consistent with intracapsular rupture.
