Residual Capsule and intercapsular debris

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RESIDUAL CAPSULE AND INTERCAPSULAR DEBRIS

AS LONG-TERM RISK FACTORS

By: Dr. Pierre Blais, PhD

Contamination of the space between the capsule and the implants by

micro- organisms, silicone oils, degradation products and gel impurities

constitutes a major problem which potentates the risk of implants. Such

problems include inflammation, infection, deposition of mineral debris, as

well as certain autoimmune phenomena. These problems can be present when

implants are in situ (in the body) and are often attributable to the

implant.

The logical expectation is that, upon removal of the implants, adverse

effects will cease. This is an unjustifiably optimistic view. It is well

documented from case histories that removal and or replacement of implants

without exhaustive debridement of the prosthetic site leads to failure and

post surgical complications.

Plastic surgery procedure lead to favor speed and immediate cosmetic

results. For these reasons, leaving or " reusing " tissue from an existing

capsule may seem more " gratifying " . However, adverse effects resulting

from

the practice are widespread but have not been well documented. Typically,

patients who require removal of faulty implants and undergo immediate re-

implantation in the same prosthetic site habitually relapse with the same

problem which motivated the previous surgery; the most common example is

exchange of implants and/or sectorizing or bisecting the capsule without

removing it completely.

Such patients rarely achieve a significant capsular correction and

habitually return for more similar surgery. A more illustrative

situation is

that where patients do not receive replacement implants. They form the

basis

of knowledge for evaluating the risks that arise from remaining

capsules. An

example is described in a paper published in 1993 (Copeland, M.,

Kessel, A.,

Spiera, H., Hermann, G., Bleiweiss, I. J.; Systemic Inflammatory Disorder

Related To Fibrous Breast Capsules After Silicone Implant Removal; Plastic

and Reconstructive Surgery: 92 (6), 1179-1181, 1993): reported problems

derived primarily from immune phenomena and inflammatory syndromes

with pain,

swelling, serologic abnormalities and alarming radiologic presentation.

Numerous similar cases have been noted amongst implant patients but

have not been the object of publications. Some are cited in FDA Reaction

Reports. Others appear in the US Pharmacopoeia Reporting Programs.

A residual capsule is not a stable entity. It may collapse upon

completion of surgery and remain asymptomatic for some time, however,

it will

fill with extracellular fluid and remain as a fluid-filled space with

added

blood and prosthetic debris. As the wall matures and the breast

remodels to

accommodate the loss of the prostheses, the capsular tissue shrinks.

Water as

well as electrolytes are expelled gradually from the pocket or else the

mixture is concentrated from leakage of water from the semi-permeable

capsular

membrane wall.

In most cases, calcium salts precipitate during that stage and may

render the

capsule visible as a radiodense and speckled zone in radiographic

projections.

Prosthetic debris is also radiodense and may be imaged to further

complicate

the presentation. The average size of the residual capsules after 6-12

months

is in the 2-7 cm range: most are compact, comparatively small and dense.

Surgical removal should present no difficulty for most patients if

adequate

radiographic information is available.

Later stages of maturation include the thickening of the capsule wall,

sometimes reaching 0.5-1cm. Compression of the debris into a cluster of

nodules which actually become calcifies follows for some patients. A few

mimic malignancies. Others appear as small " prostheses " during

mammographic

studies. They are alarming to oncologists and are habitually signaled for

further studies or biopsies by oncologic radiologists.

In light of the present knowledge and considering the probable content

of the residual closed capsules, an open or needle biopsy is not

advisable.

The risks of releasing significant amounts of hazardous contamination and

possibly spreading infective entities outweighs the advantage of the

diagnostic. At any rate, such a capsule requires removal for mitigation of

symptoms and a more direct surgical approach appears more economical

and less

risky.

In summary, a capsule with a dense fibro-collagenous wall behaves as a

bioreactor. Worse yet, it is fitted with a semi-permeable wall that may

periodically open to release its content to the breast. The probability of

finding the space colonized with atypical microorganisms is elevated

and the

control of infective processes by classic pharmacologic approaches is

difficult if not impossible.

Such closed capsular spaces may be comparable to " artificial organs "

of unpredictable functions. Their behavior will depend on the content

and the

age of the structure, its maturity and the history of the patient.

There is a

high probability that these capsules will continue to evolve for many

years,

adding more layers of fibro-collagenous tissue and possibly granulomatous

material. If bacterial entities are present within the capsule space, they

can culminate in large breast abscesses with

will resist conservative treatments.

Even with less active capsules containing mostly oily and calcitic

debris, the thickening of the wall leads eventually to solid " tumor-like

structures " and are, by themselves, alarming on auscultation and self

examination. At best, such structures are unique environments for protein

denaturation and aberrant biochemical reactions with unknown long term

consequences.

Pierre Blais, PhD

Innoval,

496 Westminster Ave.,

Ottawa, Ontario, Canada K2A 2V1

613.728-8688,

Fax: 613.728-0687

Pierre Blais, PhD received his undergraduate and graduate degrees in

physical-

organic polymer chemistry from McGill University in Montreal, Canada,

and a

Postdoctorate Fellowship in biomaterials engineering at Case Western

University in Cleveland, Ohio. In 1976 he became one of the first

scientists

to join the medical devices and radiological health program of the

Department

of Health and Welfare in Canada. He left the department in 1989 as Senior

Scientific Advisor and formed Innoval Consultants, a firm engaged in the

design, testing and failure analysis of high risk medical systems. He has

authored over 250 publications on medical materials and their interactions

with living tissues.