Learn about the many types of ultrasound probes and their salient features.

When it comes to ultrasound, there are different types of ultrasound probes that help in testing and making up the ultrasound system. And in order to ensure that the test is carried out thoroughly well and thus provides accurate results, it is essential to be mindful of the type of ultrasound probe being used. But before getting into the details of the different types of probes in ultrasound, it is important to understand what an ultrasound probe is. 

What is an ultrasound probe?

The ultrasound probe which is also called a transducer is known to be a part of the ultrasound system that comes in contact with the patient’s body. It controls the crystals that send and receive sonic pulses. A transducer is a device that converts energy from one form to another such as a lightbulb or tv antennae. Likewise, the probe transforms electricity into sound and the other way around, and then the data is sent to the ultrasound device so that it can be processed and displayed. 

Types of ultrasound probes 

The different types of ultrasound probes are simply ascertained by seeing the shape of the probe. Every probe has a distinct peculiarity, but few of them can be used for innumerable tests. The shape and the makeup of the internal crystal help to distinguish the manner in which they portray images and the frequencies they function on. Some of the well-known types of ultrasonic probes are explained in detail below: 

1. Linear probe 

Linear probes have a flat range and appearance. The piezoelectric crystals of the linear probe are organized in a linear composition to generate a straight sound wave. Linear probes can be adapted to an extensive range of uses like vascular, breast, thyroid, tendon examinations, and more. These probes conventionally depict a rectangular beam together with close-field resolution and travel at a high frequency to initiate a better and clearer image resolution. 

2. Convex probes 

Convex probes also known as curved linear probes have a curved array that permits a broader field of view. The constitution of the piezoelectric crystals in the convex array probe is organized in a curvilinear trend. These types of ultrasound probes are complicated and can consist of over 500 components in their crystal constitution. Normally these are considered significant for more comprehensive examinations. These transducers cater to a number of purposes and are effective for vascular, abdominal, OB/GYN, nerve, and musculoskeletal diagnoses. Due to their shape, convex probes are essentially used for abdominal scans because of their outspread and extensive view. 

3. Endocavitary probe 

Endocavitary probes have an elongated probe handle and a “U” shaped lens and array. In order to scan the internal part of the body, these types of probes are used. Due to their shape, endocavitary probes do not possess a vast range of depth, but they grant a broader field as compared to convex probes. 

4. Phased probe 

Phased arrays or cardiac probes consist of a small handle with a square-shaped lens and array. Generally, they examine the pictures of the heart. Phased array probes consist of substantial depth in order to reach the heart and generate an image. The phased probe is recognized by the phased array crystal presentation. Phased array transducers have lesser crystals in them, which indicates that the crystals fire in stages to initiate the image visible on the screen. 

5. Transesophageal (TEE) probe 

TEE probes are cardiac probes that offer a blocked image of the heart by placing the probe into the esophagus and in the patient’s stomach. These probes travel in four different directions and the movement is regulated by the handle commands. 

6. 3D/4D probes 

3D probes operate similarly to 2D probes barring a moving array. Slices of images are captured from various angles by the probe’s internal array, which maneuvers sweepingly around the space. All the captured slices are assembled together to create a 3D still image or a 4D image live. 

These are some of the types of probes used in ultrasound testing which serve the requirement as well as help in providing effective results. 

How to use an ultrasound probe? 

A gel will be applied to the skin by the technician during the ultrasonic examination. As a result, air pockets that could prevent ultrasonic waves from reaching the body from forming between the transducer and the skin are prevented.

Types of probes used in ultrasonic testing 

1. Contact type probe – Ultrasonic probes known as contact probes come into direct touch with the surface of the object being studied. To prevent the piezoelectric material from wearing out, contact probes need wear plates. For the best sound transmission, a small layer of couplant is typically needed between the worn plate and transducer.

2. Normal probe- Straight Beam Single element – This kind of probe sends longitudinal waves into the material that are parallel to the surface. The ultrasound is transmitted and received using a single piezoelectric crystal. This probe is preferred for the examination of thick material and is used to inspect flaws or the back wall that is parallel to the scanning surface. Due to the significant dead zone, the standard probe is inadequate for testing near-surface fault identification.

3. Angle beam probe- Weld inspection uses an angle beam probe. Combining weld shape, fault orientation, and the presence of the weld crown necessitate an inspection of the weld from the side using an angled beam. Angle beam testing is undeniably the most frequently used method in the process of ultrasonic flaw detection. A non-normal to the material surface angle beam transfers ultrasound into the substance. In other words, the probes send the ultrasound into the substance at an angle. They are typically employed to introduce shear waves into the material. However, these probes have the ability to generate longitudinal waves within the materials in specific applications.

How many types of ultrasound are used in pregnancy? 

There are actually many different types of ultrasounds that one may come across during pregnancy, all of which have marginally different purposes. There are two main types of ultrasound used during pregnancy—transvaginal and transabdominal.

Transvaginal Ultrasound- For this kind of ultrasound, a wand-shaped transducer is placed inside the vagina. Transvaginal ultrasounds are usually used in the early stages of pregnancy in order to check pregnancy, examine the baby’s heart rate and posture, check out for signs of ectopic pregnancy and diagnose the number of fetuses present. If abdominal ultrasounds do not provide sufficient information, then they can be used later on in the pregnancy. 

Transabdominal ultrasound-  transabdominal ultrasounds make use of a transducer that is placed on the abdomen to see the baby and verify the pregnancy. Transabdominal ultrasounds are commonly performed between weeks 18 and 22 of pregnancy, however, they can also be utilized later on if a problem arises that has to be looked into or monitored.

Hence, the usage of different types of ultrasound probes helps doctors to gain a clearer understanding of certain illnesses or health issues one might be faced with, which is a fundamental aspect of the ultrasound testing process. 

Semwal Diagnostic Centre also offers other radiology tests at an affordable price. We assure you of the quality service.