Used for medical diagnosis. Can visualize internalizing organs for diagnostic ultrasound without causing any harm to the patient. However, we cannot use it to image bones or air-filled structures like the lungs. Bones (in a fetus or infant) and the lungs and lining around the lungs (when they are full or partially full of fluid) can be imaged by ultrasound. Ultrasound has various applications outside of pregnancy monitoring, including imaging the heart, blood arteries, eyes, thyroid, brain, breast, abdominal organs, skin, and muscles, to name a few. Two-dimensional (2D), three-dimensional (3D), and four-dimensional (4D) displays are all used for ultrasound scans (which are 3D in motion).

Diagnostic ultrasound’s practical applications

Functional ultrasound applications such as Doppler and color Doppler ultrasound allow us to easily visualize blood flow within vessels throughout the body or heart, providing visual aids of this movement of blood in vessels throughout. We can even use Doppler ultrasound to assess cerebral blood flow to see if carotid artery plaque obstruction exists and measure cerebral blood flow using Doppler.

Elastography, a specialized ultrasound technique used to evaluate tissue stiffness, can assist in pinpointing cancerous growths while limiting damage to surrounding tissues. Colour-coded or high-contrast maps overlaid onto anatomical images may effectively represent this data. Elastography also effectively detects liver fibrosis, the inflammation-induced formation of abnormal scar tissue in the liver.

Ultrasound plays an integral part of medical diagnostics. Ultrasound-assisted needle biopsy allows doctors to visualize the precise placement of a needle within a target area, such as breast masses or tumours. Monitoring the location and movement of catheters during artery insertion procedures and providing real-time imaging during minimally invasive surgeries also provides surgeons with real-time imaging of the surgical site.

Ultrasound can serve both therapeutic and interventional functions within medicine.

Therapeutic ultrasound is an invaluable tool for treating tissue conditions, from heating or ablation to breaking apart tissue. High-Intensity Focused Ultrasound (HIFU) utilizes focused sound waves with high peak intensities to easily target specific locations. This non-invasive procedure has shown great potential in modifying or eliminating unhealthy tissues without harming surrounding areas. By employing ultrasound or magnetic resonance imaging (MRI), doctors can precisely locate and monitor treatment areas in real time, making necessary adjustments and ensuring their success. Recent FDA approval granted HIFU approval for prostate tissue ablation, expanding upon its previously used applications of treating uterine fibroids and relieving pain from bone metastases. Beyond cancer therapy, ongoing research also investigates its potential in wound sealing, stopping bleeding, dislodging blood clots from vessels, temporarily accessing the blood-brain barrier for drug delivery, and more.