Dm. Ikeda et al., Silicone breast implant rupture: Pitfalls of magnetic resonance imaging and relative efficacies of magnetic resonance, mammography, and ultrasound, PLAS R SURG, 104(7), 1999, pp. 2054-2062
The objective of this study was to evaluate the relative efficacies of magn
etic resonance (MR) imaging, ultrasonography, and mammography in implant ru
pture detection and to illustrate pitfalls in MR image interpretation. Thir
ty patients referred by plastic surgeons with suspected breast implant rupt
ure were prospectively evaluated using MR ultrasonography, and mammography.
Imaging examinations were interpreted independently and blindly for implan
t rupture and correlated to operative findings. Surgical correlation in 16
patients (53 percent) with 31 implants showed 13 (42 percent) were intact,
5 (16 percent) had severe gel bleed, and 13 (42 percent) were ruptured. MR
sensitivity was 100 percent and specificity was 63 percent. Accuracy for ru
pture was 81 percent with MR, higher than with ultrasonography and mammogra
phy (77 and 59 percent, respectively). We describe a specific pitfall in MR
interpretation, the "rat-tail" sign, composed of a medial linear extension
of silicone along the chest wall. Seen in eight cases (four intact, three
ruptures, one gel bleed), the rat-tail sign may lead to misdiagnosis of imp
lant rupture if seen in isolation. Magnetic resonance imaging is more accur
ate and sensitive than ultrasonography and mammography in detecting breast
implant rupture. We describe a new sign (rat-tail sign) composed of medial
compression of the implant simulating silicone extrusion as a potential fal
se-positive MR finding for rupture. This article presents clinical experien
ce with magnetic resonance, mammography, and ultrasound in the diagnosis of
implant rupture and defines and illustrates potential pitfalls of MR inter
pretation, including the new rat-tail sign.