Overview

Ultrasound is a non-invasive imaging test that reveals structures and organs located internally using high-intensity sound waves. It is also referred to as sonography or ultrasonography. A sonogram is an ultrasound picture. The sonographer is the specialist who conducts an ultrasound scan.

The high-frequency sound waves used in ultrasound create real-time pictures and videoas of internal organs and other soft tissues.

 

 Types

What are the various types of ultrasounds?

Ultrasound imaging has been categorized into three major groups. These are:

1. Prenatal ultrasound.
2. Diagnostic ultrasound.
3. Ultrasound guidance for medical procedures.

 

Prenatal ultrasound

• It is also referred to as pregnancy or obstetric ultrasound.
• Its purposes include;

1.  Confirming presence of a pregnancy.
2.  Checking if a woman is pregnant with more than 1 fetus in her womb.
3.  Estimation of the gestational age of the fetus.
4.  To determine how long a person has been pregnant.
5.  Looking at the fetal movements and determine the fetal heart rate.
6.  Checking for the quantity of amniotic fluid.
7.  Determining the biological sex of the fetus.

 

Diagnostic ultrasound

• Diagnostic ultrasounds include:

1.  Renal ultrasound.
2.  Abdominal ultrasound.
3.  Breast ultrasound.
4.  Doppler ultrasound.
5.  Transrectal ultrasound.
6.  Transvaginal ultrasound.
7.  Thyroid ultrsound.

• Diagnostic ultrasounds are used for viewing internal body parts
• The transducer is placed on the skin. Sometimes, it is inserted into the body part such as birth canal.
• The kind of diagnostic ultrasound to be conducted is guided by the case being studied.

 

Ultrasound guidance for medical procedures

• Healthcare specialists can also use ultrsound to ensure they carry out medical procedures precisely.
• A common example can be using ultrasound to direct placement of a needle when fluid or tissue needs to be sampled from:

1. Cysts.
2. Organs like the liver and prostate.
3. Transplant organs such as kidney.
4. Joints, muscles and tendons.

• Apart from the above case, other medical procedures that need ultrasound guidance are:

1.  Nerve blocks.
2.  Confirming location of an intrauterine device after has been inserted.
3.  Embryo transfer for in-vitro fertilization.

 

 Experts

• A sonographer is a specialist who carries out the process of ultrasound scan.
• Images can be interpreted by other specialists such as radiologists, cardiologists, etc.

 

 Tests Details

A gel is smeared on the skin over the region that is to be examined. The purpose of the gel is to prevent formation of air pockets as this can block sound waves. The gel should be water-based and easily removable from the skin.

An ultrasound examination can take 30 to 60 minutes.

External utrasounds

A sonographer holds a transducer, presses it against the body region and moves it as required. This device sends sound waves into the body then the ones which bounce back are collected. Images appear on the monitor of a computer.

Internal ultrasounds

The transducer attached onto a probe is inserted into a body opening.

Examples are:

1. Transrectal ultrasound.
2.  Transvaginal ultrasound.
3. Transesophageal echocardiogram.

 

 Results & Follow-up

Results are obtained and interpreted by a specialist such as a radiologist. After analysis, the specialist shares the report with the doctor.

Ultrasound does not affect performance of normal daily activities. After the examination is done, one is able to return to work or normal life right away.

 

Risks &  Demerits

• Ultrasound is a relatively safe procedure. It utilizes low-power sound waves and therefore no risks have been identified.
• Demerits include:

1. It cannot be used for viewing body parts that contain gas in them or are covered by bone. For example, the lung and the head.
2. It cannot be used to view deep in the body.
3.  It may fail to be effective in obese or overweight individuals.