3D ultrasounds are a specialty service requested by doctors for specific medical concerns.
While standard 2D ultrasounds provide flat, two-dimensional images of a patient's organs and tissue, a 3D ultrasound is compiled using sound waves returning at different angles.
This allows us to capture three-dimensional images that represent your internal organs more realistically, which makes the images easier to evaluate and understand.
3D ultrasounds are ordered by OB-GYNs and or other specialists when there is a specific medical concern that they need to explore in more depth. They can be used for a wide range of applications, including fetal development issues, cardiology, breast imaging and vascular imaging.
A 3D ultrasound is performed similar to any other ultrasound – gel is rubbed on your belly or area to be examined, then the technologist will move a transducer across the area. Sound waves bounce off organs and tissue, producing a sharp image of your baby, soft tissues, or organs.
The difference here is that multiple 2D images are taken at various angles and pieced together to make a three-dimensional rendering.
Here is what you can expect during each phase of the process, in addition to details on what to bring with you to your appointment at our clinic.
In the days leading up to your 3D ultrasound appointment, drink plenty of water as this can increase the quality and clarity of your amniotic fluid (which acts as a "window" through which we can view the baby). This can impact the quality of images captured.
You will not need a full bladder for these scans, but you should have a light meal before your appointment (salad or sandwich) and a glass of fruit juice approximately 45 minutes to 1 hour prior to your appointment if you are coming in for a fetal ultrasound - this will encourage baby to be more active.
Anyone coming in for an ultrasound should wear loose, comfortable clothing around the area to be examined. You may also be asked to wear a gown.
Similar to other ultrasound tests, a technologist will move a transducer back and forth over the part of your body to be examined.
Sound waves will be transmitted through the transducer and bounce off internal tissues, then be fed back through the transducer to the computer, which creates images and displays them on a monitor.
Though most patients do not usually experience discomfort due to the pressure from the transducer, you may feel minor pressure or pain if the area being examined is tender.
If the 3D ultrasound is being performed on a young child, he or she may need to be sedated so good quality images can be captured. Parents should ask about this before the appointment and prepare as requested.
The ultrasound will take about 15 to 30 minutes and most tests are fast, painless and easily tolerable.
After the exam has been completed, the ultrasound gel will be wiped off of your skin, though some may be left behind. However, it will usually dry quickly, without staining or discolouring your clothing.
When the test is complete, you may be asked to get dressed and wait as the radiologist studies the images. You should be able to return to your normal activities immediately after your appointment.
The radiologist will send a signed report to the doctor who requested the test. If follow-up exams are needed, your doctor will discuss this with you.
Read the answers to our most frequently asked questions about 3D ultrasounds at Premier Imaging in Orléans, Ottawa.
3D ultrasounds are often used when a specific problem is suspected or to capture highly detailed images of a baby in its mother's womb.
For example, these may be used to capture detailed images of a fetus (internally and externally) and find out if there may be congenital defects such as issues with the heart or skeletal abnormalities that may not appear on a standard ultrasound. Fetal heart rate can also be checked in real-time.
3D ultrasounds are often used to capture "keepsake" sonogram images of a baby in the womb (the surface of the face can be seen instead of just the profile, making it appear more like a regular photo). This would be an elective procedure.
Parents should discuss whether this purpose is appropriate for their specific circumstances as prolonged fetal exposure to ultrasound energy with 3D/4D scanning may be hazardous.
Beyond obstetrics, 3D ultrasounds are also used for other applications such as cardiology to accurately visualize an individual's cardiac state and capture a real-time image of the heart's structures (3D echocardiography).
We can now track characteristics such as blood flow, chamber volume during the cardiac cycle and how fast the heart is contracting and expanding. This can help us detect diseases in the artery and assess defects in the heart.
In gynecology, we can use 3D ultrasounds to identify uterine adhesions, examine IUD (intrauterine device) placement, and locate endometrial polyps and fibroid tumors.
When it comes to breast imaging, 3D ultrasounds can be used to capture images of the entire breast, targeting specific areas from a variety of angles. This is especially beneficial for women who have dense breast tissue.
Vascular imaging is another application as we can monitor the dynamic movement of arteries, veins and blood cells (which can be difficult to track in real-time due to their distribution).
3D ultrasound refers to the volume rendering of ultrasound data and is similar to a 4D ultrasound (3 spatial dimensions plus 1-time dimension). The 4D ultrasound is similar to a live-motion video showing motion of a 3D object.
The data generated from a 3D ultrasound can be collected in four different ways:
Freehand: Involves tilting the probe to produce a series of ultrasound images and recording the orientation of the transducer for each slice.
Mechanical: A motor inside the probe handles the internal linear probe tilt.
Using an endoprobe: A probe is inserted and the transducer is removed in a controlled fashion.
Matrix array transducer: Points are sampled with beam steering throughout a pyramid-shaped volume.
With 3D ultrasound, our ability to make accurate diagnoses significantly improves as we are able to capture extremely detailed, real-time images at angles that may not be possible with other imaging technologies.
The risks of other ultrasound imaging techniques also apply to 3D ultrasound. Essentially, ultrasound is considered to be safe as it sends high-frequency sound waves into the body (these are inaudible to humans) and listens for the echo.
Ultrasound does not use ionizing radiation or radioactive dye, unlike other diagnostic imaging tools.
The best time for a 3D ultrasound is around the 26 to 32-week mark of pregnancy.
While 3D ultrasounds offer a more aesthetically pleasing way to examine images, the data rendered in them still originates from two-dimensional images.
If there are fetal movements of any kind, this may impact the quality of volume data and affect later planes of viewing.
The three-dimensional image is still, and information we may be able to analyze courtesy of a series of moving images (such as detection and understanding of artifacts of an image) may not be available.
We'll collaborate with your healthcare team to create a streamlined imaging and diagnostics process. Find out how we can help.