Ivalon breast prostheses: evaluation 19 years after implantation

Area of Science:

• Biomaterials Science
• Medical Device Analysis
• Histopathology

Background:

• Ivalon sponge is a polyvinyl alcohol (PVA) foam used in medical prostheses.
• Long-term implantation effects on Ivalon sponge properties require further investigation.
• Previous studies suggested significant fibrous infiltration and mineral deposition in Ivalon implants.

Observation:

• Ivalon sponge prostheses explanted after 19 years were analyzed using mechanical testing, light microscopy, scanning electron microscopy, and X-ray microanalysis.
• The explanted prostheses were encased in a 4-5 mm thick fibrous capsule.
• Internal fibrous tissue ingrowth was limited to 2-3 mm into the sponge matrix.

Findings:

• The mechanical compression properties of the explanted Ivalon sponge were identical to fresh, unused material once the external capsule was removed.
• The porous structure of the Ivalon sponge was preserved after 19 years of implantation.
• Significant calcium and phosphate deposition, observed in previous animal studies, was notably absent in this human implant.

Implications:

• The long-term mechanical integrity of Ivalon sponge prostheses is maintained by an external capsule, not intrinsic material degradation or extensive infiltration.
• These findings challenge previous assumptions about Ivalon sponge behavior in vivo, particularly regarding fibrous infiltration and calcification.
• The study suggests Ivalon sponge may be a stable long-term implant material with minimal adverse biological reactions in humans.