| What
is a biopsy?
A
biopsy is the removal of a sample of tissue from the body
for examination. The tissue will be examined under a microscope
to assist in diagnosis. Therefore, only very small samples
are needed.
Sometimes,
it is enough just to scrape over an area. This is the
case with cell examinations of the cervix (neck of the
womb).
During
examination of the large intestine, a biopsy can be taken
with forceps through a tube known as an endoscope.
In
other cases, for instance, a liver or kidney biopsy, the
biopsy is taken using a large hypodermic needle.
Liver biopsy
A
liver biopsy can be used to confirm diagnoses such as
hepatitis, cirrhosis of the liver or tumours.
The
biopsy is usually performed with the patient lying on
their left side with their right shoulder extended and
their right hand under their head. It is important to
remain in this position and to keep as still as possible.
A local anesthetic will be given to numb the skin.
A
needle is then guided between two ribs towards the surface
of the liver, and the biopsy taken very quickly.
Endometrial biopsy
this
biopsy is taken in order to examine the lining of the
womb.
If
a woman is suffering from irregular periods or abnormal
vaginal bleeding, it may reveal a hormone imbalance in
the body, polyp formation or, less commonly, the development
of a tumour.
An
endometrial biopsy can be performed in a number of different
ways.
Dilatation and curettage (D&C)
(D&C)
is a common gynecological procedure but is being replaced
by the more modern practice of hysteroscopy.
A
D&C is performed under a short general anesthetic.
The cervix is opened gradually by introducing a series
of rounded sticks or dilators. These are initially very
small but increase in size until the cervix is dilated
sufficiently to accept a curette - a small instrument
shaped like a rectangular spoon. The curette is used to
obtain a sample from the lining of the womb.
Hysteroscopy
A
fibre-optic tube with a bright light at the end is inserted
through the cervix to obtain a direct view of the lining
of the womb. Passing forceps through the inside of the
tube into the womb can make biopsy under direct vision.
This is usually performed under a local anaesthetic but
some women may be advised to have a general anaesthetic.
Other
methods have been developed to allow a small sample of
tissue to be removed from the womb lining without anaesthetic
in an outpatient clinic.
The
most common is a flexible, straw-like device with a plunger.
This allows the gynaecologist to apply gentle suction
to the lining of the womb and obtain a sample or biopsy
of tissue.
Prostate biopsy
A
prostate biopsy may be performed if abnormality is found
by the doctor or nurse while performing a digital rectum
examination (DRE).
A
trans-rectal ultrasound scan (TRUSS) of the prostate gland
may be requested to assess any abnormality felt on DRE,
or if a blood test shows an elevated PSA (prostate specific
antigen) blood test.
The
procedure takes place in hospital and is performed without
anaesthetic.
The
radiologist or urologist performing the procedure will
have requested any patients taking blood thinning agents,
eg aspirin or warfarin, to have discontinued them for
up to one week beforehand because of the risk of bleeding.
Antibiotics will be given to the patient beforehand to
cover the risk of infection.
Throughout
the biopsy, the patient lies on his side with his knees
bent and his legs pulled up to his chest.
If
any abnormality is seen on the ultrasound scan, a biopsy
is taken quickly. The patient feels a short, sharp shock
as a number of small needles move in and out of the prostate.
The
procedure can also be done without ultrasound guidance.
To do this the doctor uses a finger to guide a single
needle to the abnormal area and takes a series of biopsies,
one after the other.
After
the procedure the patient may experience some discomfort
for a short period of time and possibly notice some blood
in their urine intermittently for a few days.
Skin biopsy
When
there are changes in the skin that require further examination,
a skin biopsy may be useful. First, a local anaesthetic
is given, and then a small piece of skin is cut off with
a scalpel. Then the skin is sewn together again with a
couple of stitches. This leaves a very small, almost invisible,
scar.
Bone
marrow biopsy
A
bone marrow biopsy may be necessary for many different
diseases of the bone marrow, the blood and the lymphatic
system. The biopsy will normally be taken from the upper
part of the hip (a point called the iliac crest), but
it can also be taken from the breastbone.
First,
a local anaesthetic is given. Then a strong needle is
led through the skin and the outer part of the bone until
it reaches the softer, central part of the bone (bone
marrow). A syringe is put on the loose end of the needle
and some bone marrow is sucked out. This sample is examined
under a microscope.
Breast biopsy
This
kind of biopsy is used if a clinical examination, ultrasound
scans or a mammography reveals the possibility of a lump
or tumour in the breast. The biopsy determines whether
the lump is benign or malignant.
One
method called fine-needle aspiration or FNA uses a hypodermic
needle to pierce the skin and suck out the sample. This
may sometimes be done under ultrasound or X-ray guidance.
Another
option is a surgical biopsy, where the whole lump is removed.
Small intestine biopsy
It
is not always possible to examine the central part of
the small intestine (jejunum) with an endoscopes. In such
cases, a biopsy capsule is used to take samples from the
area.
The
patient swallows the capsule, which is connected to a
thin tube. Then, an X-ray is taken to make sure that the
capsule is in the jejunum. When the capsule is in the
right place, a partial pressure is created in the tube
by pulling back a syringe connected to the other end of
the tube. In this way, a small piece of the mucous membrane
of the small intestine is sucked into the capsule. The
membrane sample is cut off in the capsule, and the capsule
is pulled back so that the biopsy can be examined. This
is most useful in the investigation of the bowel condition
called coeliac disease.
|
Artificial Limbs