Ultrasound scanning
has been used to diagnose many diseases in small animals since the early 1980's.
It is now considered to be an essential service in all veterinary
teaching hospitals and large referral centers and many small
animal practices such as Orchid Springs Animal Hospital. The reason for this is simple: Ultrasound offers a
non-invasive, non-painful method for the diagnosis and staging of many
diseases. Ultrasound is the
best modality to evaluate fluid filled and soft tissue organs. Our ultrasound machine helps us diagnose difficult cases that may not be solved with convetional tools such as bloodwork or radiographs (x-rays).
Why
Ultrasound?
Ultrasound allows us to visualize the internal architecture
of many organs. Radiographically inapparent internal abnormalities such as
nodules, masses, cysts and abscesses cannot only be seen, but can also
be counted and measured. Although
the ultrasound examination alone is in many cases non-specific for a
particular disease, in conjunction with the animal's age, sex, breed,
history, physical exam, radiographic findings and labwork, as well as
ultrasound guided fine needle aspirates or true-cut biopsies, the
specificity for disease can be high.
Many organs that are difficult to see on plain film x-rays
(prostate) can be easily seen with ultrasound.
Real-time echocardiography (ultrasound examination of the heart)
also allows us to see the heart in motion.
From these images, measurements of cardiac contractility, areas
of abnormal wall motion, chamber dilatation and wall thickening are made
and compared to normal values. The
typical ultrasound examination requires no tranquilization or anesthesia
and is easily performed on awake animals.
Prior fasting or water withholding is NOT required.
The only patient preparation necessary is clipping of the hair
overlying the area to be scanned (the ultrasound will not penetrate
through hair) and placing coupling gel on the skin surface just prior to
the exam process. The
entire scanning takes 30-40 minutes.
Images are acquired on the monitor of our ultrasound machine as
well as on a compact disc for later viewing and as an archive in your patient record.
What Can
I See With Ultrasound?
Ultrasound is best at diagnosing abnormalities that
are discrete. An example of
this type of lesion would include a mass (tumor) in the liver.
Once found, the mass can be accurately measured for later
comparison. If the mass is
found in an organ that is not required (such as the spleen), careful
examination of the other organs (such as the liver) for the presence of
metastatic disease (tumor spread) is needed prior to surgical removal of
the "expendable" organ. Ultrasound
is used to diagnose a variety of both benign and malignant diseases such
as the presence of stones within the urinary bladder, kidneys or gall
bladder, infection of the gall bladder, urinary bladder, prostate or
kidneys, the presence of enlarged lymph nodes, abnormal blood vessels,
or free fluid within the abdomen.
It is especially good in diagnosing disease of the pancreas (pancreatitis),
adrenal abnormalities, urinary bladder wall tumors, uterine infections (pyometra)
and masses that are located behind the eyeball (retrobulbar masses).
Ultrasound can often differentiate benign prostatic enlargement
from prostatic cancer. In
animals with a history of vomiting, ultrasound can be used to evaluate
if the problem is within the liver, gall bladder or pancreas.
It can often diagnose problems that are associated with the
stomach or small intestinal wall, or see an intestinal foreign body,
thus preventing a labor intensive and costly upper GI barium study.
The diagnosis of pregnancy and fetal viability (heartbeats) are
commonly seen by 21 days post-conception with ultrasound, which is much
earlier than can be done with x-rays (42 days).
In the heart, ultrasound is at it's best, as the heart is a fluid
filled organ. Abnormalities
such as a diseased heart muscle (hypertrophic and dilatory
cardiomyopathy), fluid around the heart (pericardial effusion), and
congenital abnormalities can be diagnosed and the severity can be
assessed. Heartbase tumors,
which are rarely seen on radiographs, are easily visualized with
ultrasonography. Ultrasound
can easily differentiate fluid within the cranial mediastinum from a
mass. Recently, ultrasound
has been used to evaluate tendon abnormalities of the shoulder and knee
(stifle). Using ultrasound, we can often
diagnose problems earlier than would otherwise be possible.
This dramatically increases our opportunities for successful treatments.