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Radiology
The Radiology
Department provides a wide variety of imaging modalities, both
inpatient and outpatient, including diagnostic, CT, nuclear
medicine, ultrasound, interventional, non-invasive, vascular
ultrasound, and MRI, performed by highly skilled certified
technologists.
The
Radiologists who interpret these procedures are all
board-certified by the American College of Radiology.
MRI
(magnetic
resonance imaging)
Magnetic
resonance imaging (MRI) uses radiofrequency waves and a strong
magnetic field rather than x-rays to provide remarkably clear
and detailed pictures of internal organs and tissues. The
technique has proven very valuable for the diagnosis of a broad
range of
pathologic conditions
in all parts of the body including cancer, heart and
vascular disease,
stroke, and joint and
musculoskeletal
disorders. MRI requires specialized equipment and expertise and
allows evaluation of some body structures that may not be as
visible with other imaging methods.
How is the
MRI performed?
The patient is placed on
a sliding table and positioned comfortably for the
MRI
examination. Then the
radiologist
and
technologist
leave the room and the individual MRI sequences are performed.
The patient is able to communicate with the radiologist or
technologist at any time using an intercom. Depending on how
many images are needed, the exam will generally take 15 to 45
minutes, although a very detailed study may take longer. You
will be asked not to move during the actual imaging process, but
between sequences some movement is allowed. Patients are
generally required to remain still for only a few seconds to a
few minutes at a time.
Depending on the part of
the body being examined, a
contrast material
(usually gadolinium) may be used to enhance the visibility of
certain tissues or blood vessels. A small needle connected to an
intravenous line is placed in an arm or hand vein. A saline
solution will drip through the intravenous line to prevent
clotting until the contrast material is injected about
two-thirds of the way through the exam.
When the exam is over the
patient is asked to wait until the images are examined to
determine if more images are needed. A radiologist experienced
in MRI will analyze the images and send a report with his or her
interpretation to the patient's personal physician. This should
take only a few days or less.
What will I experience
during the MRI procedure?
MRI
causes no pain but some patients can find it uncomfortable to
remain still during the examination. Others experience a sense
of being "closed in," though the newer MRI systems have done
much to reduce that reaction. Stereo headphones are provided to
calm patients and reduce anxiety. You may notice a warm feeling
in the area under examination; this is normal but if it bothers
you the
radiologist
or
technologist
should be notified.
If a contrast injection is
needed, you may have a cool sensation at the site during the
injection. Most bothersome to many patients are the loud tapping
or knocking noises heard at certain phases of imaging. Patients
are provided ear plugs to reduce the noise level.
Ultrasound
Ultrasound imaging, also
called ultrasound scanning or sonography, is a method of
obtaining images from inside the human body through the use of
high-frequency sound waves. The reflected sound wave echoes are
recorded and displayed as a real-time visual image. No
ionizing radiation
(x-ray) is involved in ultrasound imaging. Obstetric ultrasound
refers to the specialized use of sound waves to visualize and
thus determine the condition of a pregnant woman and her embryo
or fetus.
Ultrasound is a useful
way of examining many of the body's internal organs, including
but not limited to the heart,
liver,
gallbladder,
spleen,
pancreas,
kidneys
and bladder. Because ultrasound images are captured in real
time, they can show movement of internal tissues and organs and
enable physicians to see blood flow and heart valve functions.
This can help to diagnose a variety of heart conditions and to
assess damage after a heart attack or other illness.
How is the ultrasound
performed?
The patient is usually
positioned on an examination table. A clear gel is applied to
the patient's body in the area to be examined to help the
transducer
make secure contact with the skin. The sound waves produced by
the transducer cannot penetrate air so the gel helps eliminate
air pockets between the transducer and the skin. The
technologist
or
radiologist
presses the transducer firmly against the skin and sweeps it
back and forth to image the area of interest.
When the examination is
complete the patient may be asked to dress and wait while the
ultrasound images are reviewed either on film or on a TV
monitor. Often though, the technologist or radiologist is able
to review the ultrasound images in real time as they are
acquired and the patient can be released immediately.
What will I experience
during the ultrasound?
Most ultrasound
examinations are painless, fast and easy. You will lie on your
back on an examining table. The
technologist
or doctor will spread some warm gel on your skin and then press
the
transducer
firmly against your body, moving it until the desired images are
captured. There may be varying degrees of discomfort from
pressure as the technologist guides the transducer over your
abdomen, especially if you are required to have a full bladder.
The examination usually takes less than 30 minutes.
CT
(Computed
Tomography)
Computed tomography (CT) scan,
sometimes called a CAT scan, uses special x-ray equipment to
obtain image data from different angles around the body and then
uses computer processing of the information to show a
cross-section of body tissues and organs.
CT imaging is
particularly useful because it can show several types of tissue—lung,
bone, soft tissue and blood vessels—with great clarity. Using
specialized equipment and expertise to create and interpret CT
scans of the body,
radiologists
can more easily diagnose problems such as cancers,
cardiovascular disease, infectious disease, trauma and
musculoskeletal
disorders.
How is the CT scan
performed?
The
technologist
begins by positioning the patient on the CT table. The patient's
body may be supported by pillows to help hold it still and in
the proper position during the scan. As the study proceeds, the
table will move slowly into the CT scanner. Depending on the
area of the body being examined, the increments of movement may
be so small that they are almost undetectable or large enough
that the patient feels the sensation of motion.
A CT examination often
requires the use of different
contrast materials
to enhance the visibility of certain tissues or blood vessels.
The contrast material may be swallowed, injected through an IV
directly into the blood stream or administered by
enema,
depending on the type of examination. Before administering the
contrast material, the
radiologist
or technologist will ask whether the patient has any allergies,
especially to medications or iodine, and whether the patient has
a history of
diabetes,
asthma, a heart condition,
kidney
problems or
thyroid
conditions. These conditions may indicate a higher risk of
reaction to the contrast material or potential problems
eliminating the material from the patient's system after the
exam.
A CT examination usually takes
five minutes to half an hour. When the exam is over the patient
may be asked to wait until the images are examined to determine
if more images are needed.
What will I experience
during the CT scan?
CT
scanning causes no pain, and with spiral CT the need to lie
still for any length of time is reduced. For different parts of
the body the patient preparation will be different. You may be
asked to swallow either water or a positive
contrast material,
a liquid that allows the
radiologist
to better see the stomach, small bowel and colon. Some patients
find the taste of the contrast material mildly unpleasant but
most can easily tolerate it. Your exam may require the
administration of the material by
enema
if the colon is the focus of the study. You will experience a
sense of abdominal fullness and may feel an increasing need to
expel the liquid. Be patient; the mild discomfort will not last
long.
A contrast material is
commonly injected into a vein to better define the blood vessels
and
kidneys
and to accentuate the appearance between normal and abnormal
tissue in organs like the
liver
and
spleen.
Some people report feeling a flush of heat and sometimes a
metallic taste in the back of the mouth. These sensations
usually disappear within a minute or two. Some people experience
a mild itching sensation. If it persists or is accompanied by
hives
(small bumps on the skin), the itch can be treated easily with
medication. In very rare cases, a patient may become short of
breath or experience swelling in the throat or other parts of
the body. These can be indications of a more serious reaction to
the contrast material that should be treated promptly, so tell
the
technologist
immediately if you experience these symptoms. Fortunately, with
the safety of the newest contrast materials, these adverse
effects are very rare.
You will be alone in the
room during the scan; however, the technologist can see, hear
and speak with you at all times. For pediatric patients, a
parent may be allowed in the room with the patient to alleviate
fear but will be required to wear a lead apron to prevent
radiation
exposure.
Mammography
Mammography is a specific type
of imaging that uses a low-dose x-ray system for the examination
of breasts. A mammography exam, called a mammogram, is used as a
screening tool to detect early breast cancer in women
experiencing no symptoms and to detect and diagnose breast
disease in women experiencing symptoms such as a lump, pain or
nipple discharge.
Mammography plays a central
part in early detection of breast cancers because it can show
changes in the breast up to two years before a patient or
physician can feel them. Current guidelines from the U.S.
Department of Health and Human Services (HHS), the American
Cancer Society (ACS), the American Medical Association (AMA) and
the American College of Radiology (ACR) recommend screening
mammography every year for women, beginning at age 40. Research
has shown that annual mammograms lead to early detection of
breast cancers, when they are most curable and
breast-conservation therapies are available.
How is the mammogram
performed?
During mammography, a
specially qualified radiologic
technologist
will position your breast in the mammography unit. Your breast
will be placed on a special platform and compressed with a
paddle (often made of clear Plexiglas or other plastic).
Breast compression is necessary
in order to:
-
Even
out the breast thickness so that all of the tissue can be
visualized.
-
Spread
out the tissue so that small abnormalities won't be obscured
by overlying breast tissue.
-
Allow
the use of a lower x-ray dose since a thinner amount of
breast tissue is being imaged.
-
Hold
the breast still in order to eliminate blurring of the image
caused by motion.
-
Reduce
x-ray scatter to increase sharpness of picture.
The technologist will stand
behind a glass shield during the x-ray exposure. You will be
asked to change positions slightly between images. The routine
views are a top-to-bottom view and an oblique side view. The
process will be repeated for the other breast.
The examination process should
take about half an hour. When the mammography is completed you
will be asked to wait until the technologist examines the images
to determine if more are needed.
What will I experience
during the mammogram?
You will feel pressure on
the breast as it is squeezed by the compressor. Some women with
sensitive breasts may experience discomfort. If this is the
case, schedule the procedure when your breasts are least tender.
The
technologist
will gradually compress your breast. Be sure to inform the
technologist if pain occurs as compression is increased. If
discomfort is significant, less compression will be used.
The National Cancer Institute
(NCI) adds that women who have had breast cancer and those who
are at increased risk due to a genetic history of breast cancer
should seek expert medical advice about whether they should
begin screening before age 40 and about the frequency of
screening.
The Mammography Department is
accredited by the American College of Radiology and the Federal
Food and Drug Administration. A certified technologist utilizing
dedicated mammography equipment performs the exams.
Bone Density
Every day, physicians use
radiography, or x-rays, to view and evaluate bone fractures and
other injuries of the musculoskeletal system. However, a plain
x-ray test is not the best way to assess bone
density.
To detect osteoporosis accurately, doctors use an enhanced form
of x-ray technology called dual-energy x-ray absorptiometry (DXA
or DEXA). DEXA bone
density
is today's established standard for
measuring bone mineral density (BMD). DEXA is a quick, painless
procedure for measuring bone loss. Measurement of the lower
spine and hips are most often done. More portable devices that
measure the wrist, fingers or heel are sometimes used for
screening, including some that use ultrasound waves rather than
x-rays.
How is the bone density
performed?
The bone density test takes
from 10 to 30 minutes, depending on the equipment used and the
parts of the body being examined. You may be asked to undress
and put on a hospital gown. Then you'll lie on a padded table
with an x-ray generator below and a detector (an imaging
device). (see photo)
Most often, doctors focus on
bone loss in the spine and hip where most osteoporosis-related
fractures happen. During an examination of the spine, your legs
will be supported on a padded box to flatten your pelvis and
lower (lumbar) spine. To assess your hip, the technologist will
place your foot in a brace that rotates the hip inward. In both
cases the detector is slowly passed over the area, generating
images on a computer monitor.
What will I experience
during the bone density procedure?
DEXA bone
densitometry
is a simple, non-invasive procedure. Once on the table you may
be asked to hold an awkward position for a short time while the
arm of the machine passes over your body taking measurements. It
is important that you stay as still as possible during the
procedure to ensure a clear, useful image. No anesthesia is
required. The procedure is painless and radiation exposure is
minimal.
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