Ultrasound are sound waves with frequencies that are higher than what humans can hear. They are used for several purposes including in diagnostic imaging. With the use of ultrasound, internal body structures like bones, muscles, joints, and other internal organs are seen. They are also used for assessing pregnant women to create visual images of the developing embryo or fetus.
It was decades ago when ultrasound was first used for medical purposes. The first doctor to have used it for the human body is Dr. George Ludwig of the Naval Medical Research Institute. Another early user of ultrasound is John Wild, an English physicist. He was the first one to use ultrasound to assess the thickness of bowel tissue.
The use of ultrasound has changed the way some things are done in medicine.For instance, in anesthesiology, ultrasound is used to guide anesthesiologists in administering anesthetics especially if these drugs are administered near the nerves. In gastroenterology, ultrasound is used to identify inflammation as well as for determining fecal incontinence. Other areas of medicine where ultrasound has practical purpose include cardiology, emergency medicine, head and neck surgery, neonatology, neurology, obstetrics, ophthalmology, pulmonology, and urology.
Unlike other types of diagnostic machine, ultrasound machines are capable of producing images without emitting harmful radiation like those of x-ray machines. Hence, they are very safe to use even for pregnant women.
Many of the doctor’s offices and clinics these days are equipped with ultrasound machines which makes it easier for them to examine patient’s internal organs without having to send them to medical imaging centers. These machines are portable and inexpensive to use compared to using magnetic resonance imaging (MRI) and computed tomography (CT). Ultrasound machines are cost-effective solutions for medical imaging needs.
The basic parts of an ultrasound machine are the display, the transducer probe, the central processing unit (CPU), the keyboard, hard drive storage, printer and video recorder.
Of all the parts of an ultrasound machine, it’s the display that’s considered to be the most recognizable part of the unit. It is where the information coming from the CPU is translated and displayed. The clarity of the images displayed on the monitor depends on the model and resolution of the display.
One of the most important parts of an ultrasound machine is the transducer probe. Without it, there will be no data to pass on to the CPU and to be displayed on the monitor. The transducer probe acts as the mouth and ears of the machine. It emits sound waves to the patient and receives the vibrations. The information collected by the probe is then passed on to the CPU.
If the transducer probe is considered to be the mouth and ears of the machine, then the CPU is the brain. It’s a computer that makes use of a special kind of software that translates the data passed by the probe into visual images that doctors can use to view specific organs.
Just like computers, an ultrasound machine also has a keyboard that a technician can use to enter patient information or procedure findings.
The ultrasound machine also has a hard drive storage where data can be stored for later retrieval. Information can also be stored in a DVD or digitally for easy access.
The purpose of the printer is simply for printing out images from the procedure done for later study or to be taken home especially by expecting mothers.
In some models of ultrasound machines, a video of the procedure can be taken for later viewing.
The transducer probe is one of the main components of the machine. Without it, the ultrasound machine won’t be able to do what it is supposed to do.
It’s the transducer probe that makes the sound waves and receive the echoes. It is through the principle called piezoelectric effect that it is able to emit and receive sound waves.
Transducer probes come in a variety of shapes and sizes. Its shape determines its field of view while its frequency of emitting sound waves determine the depth of the penetration of the sound waves as well as the resolution of the image.
There are multiple-element probes or transducer probes containing more than one crystal elements. In this type of probes, each crystal has its own circuit and has an advantage over single-element probes as the beam can be ‘steered.’ This is highly useful for cardiac ultrasound.
Probes are also designed differently depending on their use. Some probes are designed to be inserted into different openings of the body including the esophagus, vagina, and rectum. These probes are specifically created to get them closer to the body organ being examined. The closer they are to the organ being examined, the more detailed the resulting image is.
Choosing for ultrasound transducer depends on the following factors:
The frequency of the transducer can affect the clarity of the image. Higher frequency transducers provide more detailed image. The higher is the frequency, the deeper is the penetration to the body organ to be examined.
The footprint pertains to the area of the transducer that comes in contact with the patient. Annular array transducer provides the smallest footprint while linear and convex arrays provide a wide footprint which can be quite challenging to completely come in contact with the patient’s skin.
This refers to the frequency an image is updated. This is an important factor to consider when assessing moving interfaces. For instance, you cannot use mechanical transducers for cardiac ultrasound as their frame rates are too slow; you will need a transducer with faster frame rate for this.
Some transducers come with added function like the ability to hold biopsy guides or can be used for intracavity assessment. So you need to know exactly your purpose for buying a transducer and the added feature that you’d like to have before making a purchase.
Whether it’s for your first purchase or for replacement, you should opt for a reputable medical equipment vendor when buying ultrasound probes and transducers.Absolute Medical provides a wide selection of internal and external ultrasound probes and transducers. They carry products from trusted brands like GE, HP, Siemens, and Philips.Check out their site for a full list of ultrasound probes and transducers here.