Volume Imaging and Focused Ultrasound: The Only Non-Invasive Method to Treat Tumors

The report released by the American Cancer Society is worth noticing. Approximately 2 million people are projected to get diagnosed with cancer in 2023 and about one-third of them are estimated to die of the disease. It is thus critical to find effective ways to fight against the dreaded disease. The effectiveness of radiation therapy is still limited and often takes a heavy toll on the patient. Even the diagnosis of tumors is reliant upon biopsy - a highly painful procedure. Medical and scientific researchers are thus constantly looking for a non-invasive technique to diagnose abnormal tissue growth inside the body's internal structures. The development of volume imaging has emerged as a ray of hope in detecting tissue abnormalities. It has the potential to transform the way these abnormalities are detected and treated.

What is volume imaging? 

Volume imaging is a new kind of ultrasound imaging technique. It is used for analyzing tissue volume by collecting a large amount of volumetric data and processing it for a 3D display. This new imaging technique helps in understanding the structural properties of tissues and its surrounding environment in great detail. It is a considerable improvement upon the conventional 2D images, produced by regular ultrasound machines. It holds immense potential in radiology, like the accurate detection of malignant tumors and focused ultrasound therapies.

The characteristic features of this imaging technique are described below.

●     High channel count: Ultrasound machines with a higher channel count have the ability to produce more detailed images with less noise. Channel count means the number of independent channels used to transmit and receive ultrasound waves. So far we’ve seen 256 or 512-channel count solutions, however, there are manufacturers who’ve developed even 1024 and 2048-channel solutions.

●     Rapid data acquisition: Since there are multiple channels operating in the ultrasound machine, you can acquire data from several sources simultaneously. The data from a 512 or 1024-channel solution can be acquired in a fraction of the time when compared to machines with lower channel counts. Faster data acquisition ultimately helps in improving the signal-to-noise ratio as well as the frame rate of the image.

●     Multi-directional focus on structural properties: With the volume imaging technique, you can get a multi-directional focus on structural properties of tissues and blood vessels. This is done by a process called beamforming. During the beamforming process, multiple beams of ultrasound waves are focused at a single point from different directions. It inevitably improves the image quality of the object under focus.

●     3D image display: With this imaging technique, researchers get a three-dimensional image of the internal structure. It is created by putting together a series of 2D images from different angles into a single 3D image. A more realistic and detailed picture of the object thus emerges out of this exercise. Image-guided procedures like ablations become much easier with a 3D image.

●     Blood flow characterization: It is also used to measure the velocity of blood flow. This is valuable when you're diagnosing conditions like stenosis and occlusion (blockage of blood vessels). The measurement of blood flow is crucial to detect underlying cardiovascular diseases.

●     Reference for focused ultrasound therapies: This imaging technique has made focused ultrasound therapies for the ablation of tumors safer. The 3D image produced serves as a reference point to focus high frequency ultrasound beams at the precise location within the organ system. The target tissue can be monitored well during the process, reducing the chances of side effects to a large extent.

What is focused ultrasound?

Focused ultrasound (FUS) is a non-invasive therapeutic technology that uses high-intensity ultrasound waves to target and ablate (destroy) diseased tissue without harming surrounding healthy tissue. FUS works by focusing a beam of ultrasound energy on a specific location in the body. The ultrasound energy heats up the tissue at the target location, causing it to die.

FUS is also known as high-intensity focused ultrasound (HIFU), is a medical technology with various applications:

1. Tumor Ablation: Focused ultrasound is used to destroy cancerous tumors without the need for surgery. It precisely targets and heats the tumor tissue, causing coagulative necrosis.

2. Pain Management: It can be employed to alleviate chronic pain conditions such as trigeminal neuralgia and back pain by disrupting pain-transmitting nerves.

3. Uterine Fibroids: Focused ultrasound is used non-invasively to shrink uterine fibroids, reducing symptoms like heavy menstrual bleeding and pelvic pain.

4. Prostate Cancer: HIFU is employed for prostate cancer treatment, often as an alternative to surgery or radiation therapy, with fewer side effects.

5. Bone Metastases: It can help relieve pain caused by bone metastases in cancer patients by destroying tumor tissue in the bone.

6. Blood-Brain Barrier Opening: Researchers are exploring the use of focused ultrasound to temporarily open the blood-brain barrier, allowing for targeted drug delivery to treat brain diseases.

Key Takeaway

New ultrasound diagnosis techniques like volume imaging have brought us one step closer to non-invasive cancer treatment. The high channel count system of these ultrasound machines gives a multi-directional approach to studying the underlying tissues and internal structures. The rapid data acquisition along with the high-resolution 3D image researchers get with this technique is immensely helpful in providing quick and targeted healing solutions.