The cold and gooey substance which is applied before an ultrasound is called the ultrasound gel. It serves various purposes during ultrasound imaging. The following article provides information about different types of the gel along with the uses.
Ultrasound imaging has evolved to be a very useful diagnostic tool in medical sciences. In this technique, sound waves are projected on the body parts, which bounce back and are collected by computer to generate images of the internal organs. Sound waves cannot penetrate bones and thick tissues, hence these structures can be clearly seen in the image generated.
The technique is widely used for fetal monitoring, diagnosis of malignant cell growth, and general study of several other body parts. The images generated by this instrument can also be used for various diagnostic procedures. The gel plays a very important role during ultrasound imaging. The gel mainly contains propylene glycol, glycerin, and phenoxyethanol. These ingredients are effective solvents and moisturizing agents which can be safely applied to the skin. These are absorbent in nature.
In this technique, sound waves are sent to the internal organs through an equipment called the transducer. It emits sound waves of the desired frequency, which pass the patient’s skin and enter the body cavity. After colliding with the solid structures inside the body such as bones, tissues, etc., these waves are reflected back and collected by a computer analyzer.
Images are then generated on the computer screen, which allow the doctor to study the internal organs or the fetus. The gel is also used with a fetal Doppler, which enables the doctors and parents to hear the fetal heartbeat. Sonographers (the professionals who operate the machine) can also study blood circulation to various organs by using this machine.
For the sound waves to travel through the patient’s body and come back, a clear, air-free medium is required, as air impedes the path of the sound waves. The gel is applied to generate an air-free environment. A layer of this gel is applied on the patient’s skin, between the transducer and the part of body to be imaged. The gel prevents the formation of air bubbles, and ensures that the sound waves are transmitted without meeting any obstacle. Beside this, the gel also lubricates the skin so that the transducer glides smoothly on the patient’s skin. Precision is required while positioning the transducer to get perfect images.
Types of Gel
Different types of gels are used by different technicians and the ingredients may also vary as per the brand or manufacturer. These gels are available as clear and transparent gels or green, white, or blue gels. The consistency of these gels also differs to a great extent, starting from very thick to very light gel formulation. However, no matter what the consistency of the gel, it never drips off the skin, and always adheres to the skin. Similarly, the thick consistency of gel never feels uncomfortably sticky to the skin and gets easily wiped off the skin.
The decision regarding which type of gel to use is strictly a technician’s prerogative. The brand, consistency, color, and type of the gel does not interfere with the results of the ultrasound imaging in any way. All the gels are formulated to work in the same manner. The only problem with these gels is that they are very cold, and hence the patients may find it a little uncomfortable. However, some technicians may use special warmers before applying it on person’s exposed body parts.
Ultrasound pads may be used, either as a substitute for the gel or to enhance the transmission while taking the images of the superficially located organs.