Scanning electron microscopy and X-ray microanalysis of foreign bodies associated with silastic implants in humans

CONTRACEPTION SCANNING

ELECTRON_MICROSCOPY

MICROANALYSIS

OF FOREIGN

SILASTIC

AND X-RAY

BODIES

IMPLANTS

ASSOCIATED

IN

WITH

HUMANS

Arthur H. Tatum, M.D., Ph.D.’ John D. Shelburne, Peter

M.D., Ph.D.’

Ingram, Ph.D.*

Dale N. Robertson, Horatio

8. Croxatto,

S.

‘Department

of Pathology,

Ph.D.3

Diaz,

M.D.4

M.D.4

Duke University

and V.A.

Medical Centers,

Durham, North Carolina *Research

Triangle

3Population

Institute,

Council,

4Consultario

Research Triangle

Park, North Carolina

New York, New York

de Planification

Familiar,

Santiago,

Chile

Abstract Polydimethylsiloxane been

implanted

traception. reaction giant

(Silastic)

in

Histological around these

cells.

steroids,

seemed unlikely Analysis

scanning electron

microscopy,

gloves

was talc. during

fragmentation

the could

The talc

containing

revealed

authors since

the

megestrol

as a method

of

crystals

tissue

foreign

had been

processed

and X-ray microanalysis

demonstrated

as a contaminant

Further

analysis

not have produced the material

showed that since

Silastic

as with

microscopy,

was probably

implantation.

body

these crytals

by polarization

introduced

have con-

in multinucleated

had interpreted

of these crystals

acetate

long-term

a granulomatous

with birefrinqent

several

solvents.

material

tissue

studies

capsules

Although

this

organic

capsules

subcutaneous

that the from

capsule particles

could not be detected. Submitted for publication Accepted

for publication

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January 25, 1984 February 3, 1984

1983 VOL. 28 NO. 6

543

CONTRACEPTION

Introduction Polydimethylisiloxane that steroid This

(Silastic)@*

hormones diffuse

characteristic

has

implanting

subcutaneous

megestrol

acetate.

used

capsules

giant

reaction

had not

foreign

material

cells

been

microscopy

crystals

were steroid,

were not removed ethanol

and

was studied

this

et at.

by

agents

as

characterized

was seen.

Silastic

involves

the and

was that the the crystals

treatment

seemed unlikely, by scanning

by

Since this

implants,

since

However,

interpretation

such

was studied

autoradiography,

(which

(I).

with

and similar

electron

microscopy

implants

containing

and X-ray microanalysis.

megestrol

acetate

prepared

dehydrated

tissue

and deparaffinized after

slides

light

6. Croxatto,

microscopy

Sections

Tissue

for light

electron

analyzer

microscope with

microscopy

sectioned

for SEMwere lifted

as described

and consisted

that had been fixed

embedded in Paraplast,

with xylene.

X-ray

Silastic

from Dr. Horatio in IX 0,04.

alcohols,

examined in an ETEC scanning dispersive

around

and unembedded tissue

and post-fixed

in serial

and Methods

from

was obtained

glass

glutaraldehyde

energy

rates

Their conclusion

metabolites.

in our laboratory

Human subcutaneous

slides

(2).

embedding

Material

of

with

property

contraception capsules

reaction

crystals

observed

or steroid

xylene),

body

these

by histochemistry,

by Ermini

by paraffin

material

predictable

progestational

surrounding

foreign

previously

the useful

experimental

and birefringent

was studied

electron

for

containing

tissue

granulomatous

multinucleated

(SEM)

through them at slow,

been

When the

histologicslly,a

membranes possess

by Pickett equipped

off

at

in 4X was 8 u,

the glass

--et al. (3) and with a Kevex 5100

a 30 mm2 silicon-lithium

detector

(4,5). Results As a control,

megestrol

acetate

* Silastic is the registered polydimethylsiloxane.

544

crystals

were implanted

in autopsy-obtained

trademark for Dow-Corning Corporation’s

DECEMBER

brand of

1983 VOL 28 NO. 6

CONTRACEPTION

subcutaneous

tissue,

technique.

The steroid

from implant crystals

dissolve.

sections

glass

and,

2 show the same crystal, note

the

adipose

similarity

cells.

plate-like

Figure

2 also

crystal Figures

magnesium, respectively, in all

visualized silicon

with

observed

the laminsr

X-ray

7 is

increase the

large

particle

which

shows that

a light

(lower the

the

crystal

of

0.27.

of multinucleated it

micrograph

did

not

taken

of

stacked

by the backscatter

same crystal

that the

that silicon

is

for silicon

and shape that was

X-ray spectrum

composed

Other giant

stopped down to

microscopy

numlerous small

Figure

contain

several

magnesium,

increased

density

as compared to background,

silicon

map.

A large

and a typical

dispersive

as a Ka

When the foci

of

but with much less X-ray

spectrum

a

distributed

presented

silicon. showed

Figure

demonstrating

number of the small cytoplasmic

energy

1983 VOL. 28 NO. 6

areas

cell.

particles

9 is the same field

the

birefringence.

electron

and

was

and, although

strong

cell

by scanning

the

material

in the giant

left)

of

of magnesium and

foreign

cells,

exhibit

and

and magnesium are

with the condenser

than the

DECEMBER

composed

material

cytoplasm.

was mapped for

spot-probed,

1 and

and then by SEM;

of the refractile

X-ray Si map showing that the particles area

off

Figures

of the surrounding

with the same size

the

ratio

refractile,

same giant

throughout

by polarization

and demonstrates

Figure 6 is an energy dispersive

the contrast

8 is

is

structure

which demonstrates

a peak height

was quite

crystal

maps of

of the crystal

in the cytoplasm

material Figure

portions

by SEM.

same crystal

the

were

dense.

4 and 5 are Ko

present

shows

con-

were lifted

microscopy,

and orientation

Figure 3 shows the same crystal

which accentuates is electron

shape,

hot

crystals

microscopy.

by polarization

but the

was not changed.

material

electron

sections

with

acetate

were photographed

by scanning

first

Tissue

materials

birefringent

of the size,

structures.

technique

patients

embedding

end xylene,

were treated

megestrol

the foreign

containing

and studied

treatment.

sections

experiment,

paraffin

with ethanol

although

from implant

slide

standard

treated

Other

acid,

and sections

by

wss removed by this were also

in a control

microscopy the

not

sulfuric

destroyed Tissue

patients

did

centrated

processed

and

same

slightly intensity

bodies is

were

shown in

545

CONTRACEPTION

Figure 1. Birefringent crystal by polarization microscopy. 350X

Figure 2. Scanning electron micrograph of the same crystal as Figure 1 (serial section). Note

the

similar

distribution

of

the

adipocytes, and laminar structure (arrow). 450x

546

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1983 VOL. 28 NO. 6

CONTRACEF’TION

Figure

3.

crystal

from

Figure

DECEMBER

4.

Backscatter

(Figure

silicon

within

2) the

28 NO. 6

image

2.

K c1 X-ray

crystal

1983 VOL

Figure

of

identical

450X

silicon

showing crystal.

map for

the

the distribution

same of

325X

547

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Figure 5. Ka crystal

X-ray magnesium map for the same

(Figure 2) showing

distribution

of

magnesium

the ident ical but

decreased

intensity. 325X

Figure 6. Energy dispersive X-ray spectrum of the same crystal (Figure 2) with a peak height ratio of Mg/Si=Cl.27.

548

DECEMBEK

1983 VOL 28 NO. 6

CONTRACEPTION

Figure

7.

Light

body

foreign refractile

giant

lower

left

Figure

8.

Scanning

large

cell cleaved

granules.

of

cell

granular

Note large

(arrow).

body

in the

480X

electron

(Figure body

a multinucleated

containing

material.

cell

identical

DECEMBER

micrograph

7). (arrow)

micrograph Note

the

and other

of

the

single smaller

1200X

1983 VOL. 28 NO. 6

549

CONTRACEPTION

Figure 9. Ka

X-ray silicon map of identical

cell as Figures 7 and 8 showing the same distribution of particles. 1200X

Figure 10. Energy dispersive X-ray spectrum of a particle in a giant cell with a peak height ratio of Mg/Si=0.04.

550

DECEMBER

1983 VOL. 28 NO. 6

CONTRACEPTION Figure 10.

The magnesium

to silicon ratio is about 0.04, but every

particle probed contained detectable magnesium in addition to the prominent silicon peak.

Discussion The

foreign material associated with Silastic capsules and granulomatous

inflammation contained magnesium and silicon and had a stacked laminar structure by SEM and backscatter. These data establish the identity of the material as talc, a magnesiwn silicate. The talc was probably introduced with the capsule as a contaminant from the physician's gloves. Although talc is no longer used on gloves in the United States, because of the granulomatous

reaction it induces, it was still in common use In South

America when these capsules were implanted. The large crystals (30~ much more magnesium cells.

) had

than the smaller bodies within the cytoplasm of giant

This probably represents leaching of magnesium

from the silicate

network by the acidic conditions inside lysosomal vesicles and/or chelation by organic triphosphate. Special care was taken to spot-probe many small crystals with low magnesium content to rule out the possibility that they could represent fragments of Silastic capsules which would only contain silicon.

No silicon-only particles were found. Another possibility was

that fragmented Silastic absorbed magnesium from tissue fluids.

This was

excluded by studying slices of capsules that had been implanted in humans. No magnesium was detected near the surface of the capsules or deep wlthln them.

Similar material around Silastic capsules was studied by Erminietg. by histochemistry

(2)

and autoradiography using 14C-megestrol acetate. Since

some of the crystals stained positively by the Shultz and dlgltonin reactions and were positive by autoradiography, they concluded that the crystals

were megestrol

photographs

acetate

or a metabolite.

Their published

show that although foci of positive staining are evident, the

positive areas are predominantly

at the periphery of the crystals with

negative staining centers. This pattern is exactly what would be predlcted if steroid diffused out of the capsule and was adsorbed on the surface of talc particles. Steroids are frequently chromatographed using silicates as the stationary phase, and it is reasonable that adsorbed steroid would

DECEMBER

1983 VOL. 28 NO. 6

551

CONTRACEPTION remain

in tissue

the crystals

sections

were just

anisotropy

demonstrated

around

insertion

procedure.

that the particles

Silastic

implants

found

It

tissue. fibrosis

is

is

We have ruled

of the polydimethylsiloxane and we have

treatment

with organic

it would be quite

difficult

solvents.

If

to explain

the

by autoradiography.

In summary, we conclude reaction

even after

steroid,

likely

steroid

the

granulomatous

from contamination

resulted

of

that

may be eliminated

talc

in the

out the possibility

capsule

no evidence

observed

that

during the

fragmentation

in the granulomatous crystals

granulomatous

in the reaction

by measures taken to prevent

reaction,

subcutaneous and excessive

talc

contamination.

Council

(I.C.C.R.),

Acknowledgement This

investigation

Rockefeller

was funded

University,

by the

Population

New York, New York References

1.

Kincl

FA,

Eengiano G, Angee I:

preparations.

I. Diffusion

membranes. Steroids 2.

of various

11:673-680,

contraceptive

effects

Pickett

JP, Ingra

particulates

steroids

with subcutaneous 73~360-373,

copy and X-ray microprobe

hormonal through polymer

G:

Studies

on sustained

polydimethysiloxane

implants.

1973

P, Shelburne

in a single

release

1968

Ermini M, Carpino F, Fusso M, Benagiano, Acta Endocrinologica

3.

Sustained

JD:

histologic

Identification section

analysis.

of inorganic

using both

light

J of Histotechnology

micros-

3:155-158,

1980. 4.

Shelburne JD, Ingram P, Hawkins HK: inclusions.

Scanning Electron

Research Institute, 5.

Masters SK, Bell

Chicago,

microanalysis. Editor.

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SEM Inc.,

Microscopy/l976 Ill.,

SW, Ingram P:

and freeze-sectioning

(Part

III),

1.1-T.

pp. 485-492 Preparative

macrophages

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1983 VOL. 28 NO. 6