General Information on Radiological Evaluation of Prostheses:

Radiographic studies can diagnose prosthetic problems, predict implant-related breast diseases and determine the condition of prostheses in situ. Specialized study techniques can be employed to obtain specific information on the prosthetic system but good quality mammograms intended for routine cancer screening are still valuable resources for studies targeting the implants. Mammographic anomalies in the tissues surrounding implants generally precede symptomatic failures. Most patients undergo mammographic studies during their 30s and 40s. Such records are retained by most centers and are often available for review. It is important to extract all possible diagnostic information from such existing mammographic studies before submitting users to new ones in order to minimize radiation exposure. This also reduces the cost of supplemental radiographic studies that may become necessary for prosthetic failure follow-up.

Limitations:

1. Radiological facilities do not generally provide medical diagnostic information on tissue pathologies or on implant failure. Most of their activities center on cancer detection.

2. The presence of gel-filled prostheses modifies the radiographic presentation of breasts but does not exclude successful cancer screening by manual or radiographic techniques.

3. Implants can obscure tumors. Dominant or clinically suspicious breast masses should be investigated without delay through biopsy or other recognized cancer diagnostic methods to establish their risk.

4. Diffuse or amorphous (non-calcific) densities in tissue surrounding prostheses are commonplace and may be related to ingress of prosthetic materials and their degradation products into the breast. These phenomena further confuse the diagnostic of failure.

5. Significant amounts of impure silicone oils from the filling gel can leak out of superficially intact prostheses. Quantities accumulated and the rate of leakage are device-type and time dependent. Such leakage may mimic gross gel spillage and/or shell rupture on some radiograms.

6. Techniques used for evaluating the integrity and the residual lifetime of implanted prostheses are still in the investigative stage. Their reliability depends on the type, number, quality, projection angles and the time elapsed between successive radiographic studies.

7. In the light of present knowledge, the radiographic detection of an anomaly suggesting loss of integrity of the shell in a gel-filled prosthesis or a multi-lumen prosthesis is not subject to false positives. In such cases, the patient should seek prompt medical and surgical attention, in particular if the implants are older than 7-8 years.

8. However, the apparent absence of prosthetic damage or radiographically evident tissue anomalies are subject to false negatives. Such observations do not exclude the possibility of small perforations, tissue damage, implant-related breast diseases or adverse reactions due to long term diffusion of low radiodensity prosthetic debris into breast tissues.

9. Patients with complex medical histories involving prior prosthetic misadventures may exhibit a progressive increase in periprosthetic tissue density that can mimic extravasation of their current prostheses. Earlier ruptures with gel residuals always complicate the interpretation. For this reason, it is important to know the patient’s prior history.

10. Periprosthetic radiolucent zones, well defined radiodense entities in the intracapsular space and persistent symptoms coinciding with long term prosthesis usage or silicone oil injections generally introduce major complicating factors which reduce the accuracy of the failure diagnostic.

11. Fiber optics visualization of the intracapsular space with implants in situ using invasive percutaneous techniques is strongly contraindicated. The attendant risks to such procedures increase rapidly with the age of the device.

12. Prostheses disturbed by tissue sampling procedures performed incidentally to open capsulotomy or devices removed for any reason cannot be returned to the surgical site or reused without risking early rupture and/or serious infective complications. Such products cannot be safely sterilized by any known method.

13. Tissue capsules surrounding prostheses cannot be salvaged for reconstruction using tissue translocation techniques. This is because of their elevated level of contamination and the risk of forming closed pockets, seromas or hematomas. Ablative capsulectomies are indicated for all removals and when tissue cover of the surgical site is not compromised.

14. Compressive manipulation of the breast for mammography, for manual appraisal of tumors or for cosmetic capsule release (closed capsulotomy), entails significant risks of shell and capsule rupture with possible intracapsular bleeding. These risks increase with the age of the device. Such procedures cannot be safely performed on most devices after 2 years in situ or on any patient exhibiting radiographically visible periprosthetic breast calcification.

15. Radiographically evident calcification, in particular organized calcific structures with diffraction effects constitute definitive indication for prostheses removal. They habitually indicate a perforated prosthesis. Such crystalline entities have the capacity to excoriate and puncture shell walls.

16. Xeromammographic techniques are a superior option for prosthetic evaluation and surrounding breast tissue studies. When available, such techniques should be used first in order to minimize medical cost of prosthetic evaluation. Alternate screen film techniques require optimization of exposure and angle in order to produce comparable results.

17. Advanced evaluation techniques such as CAT, MRI, PET, Ultrasonnography, Diaphanography, Doppler (blood flow) measurements, Imaging Thermography and other techniques involving Gamma Camera (radio-isotope) studies may provide additional diagnostic information. However, costs are greater and the interpretation is correspondingly more difficult and laborious.