Terahertz Pulsed Imaging™, or TPI™, uses a type of pulsed wave that is non-ionizing and less hazardous to use than X-ray. Its power levels are typically lower than background terahertz radiation encountered in everyday life. It has the potential for:
- Earlier detection of epithelial tumors
- Reduced treatment costs
- Lower morbidity rates
The creator of this technology is TeraView, a company that has nearly 20 years’ experience in the pioneering use of terahertz waves for the detection of skin and other surface cancers. Terahertz are a form of magnetic radiation that are both safe to use and non-ionizing. This makes them an ideal tool for the detection of cancer.
Teraview has been working in conjunction with several UK institutions to conduct in vivo trials of skin cancer detection using a terahertz probe. The results have shown the probe has good specificity and selectivity. Further work has also been done on mouth and throat cancers.
The preliminary ex vivo tests were conducted with a unit similar to the TPS Spectra 3000. Beyond this TeraView has developed a hand held probe which links to the same base unit.
TeraView has designed numerous terahertz algorithms that have been shown to be effective at spotting differences between healthy and cancerous tissue. However, as terahertz waves have a limited penetration depth in the human body, such applications are limited to surface cancers or as an intra operative probe.
Non-invasive Molecular Imaging of Epithelial Cancer
The epithelium is the origin point for an estimated >85% of all cancers. The current gold standard for cancer diagnosis is an excision biopsy to extract tissue from the body and examination under a microscope. This method relies on a relatively large amount of tissue, but TPI™ technology could reduce this amount and improve conventional biopsy and associated surgery through greater precision in identifying the areas to be excised.
This would reduce the number of procedures and facilitate earlier and more accurate diagnosis. As the technology matures, TPI™ may become the sole instrument of biopsies, making possible point of care optical biopsy.
A feature unique to TPI™ is the ability to produce 3D images at high resolution through thick tissue using molecular markers, such as water, to output spectral and absorption data that allows differentiation between cancerous and non-cancerous tissues. This is done non-invasively and using non-ionizing radiation.
TeraView is working alongside clinical customers and partners to provide imaging and spectroscopic capabilities from their instrumentation for tissue and disease classification ex vivo on excised tissue. They are also actively engaged with partners to develop in vivo intra-operative probes for tissue conservation surgery and endoscopic applications on patients. There has been extensive work on skin and basal cell carcinoma, and that has recently expanded to clinical work on breast and other types of tissue using these capabilities.
Use of Terahertz as an Intra-Operative Tool during Breast Cancer Surgery
Terahertz waves allow real-time confirmation of the elimination of all cancer tissue, drastically reducing the need for subsequent operations. When a surgeon is removing cancerous tissue, they are making their best estimate of the location of the diseased tissue.
Once removed, the tissue is sent to biopsy, where the margins are checked. This is the verification that the tissue is surrounded only by healthy cells. A check of synaptic nodes is also routine in breast surgery that again requires samples to be taken and sent for biopsy.
The biopsy can take 2-3 weeks and even then in up to 30% of cases women are called back for a second operation. This need for recalls can be avoided, by having equipment that can perform this test in real time.
Histology and Terahertz Image Overlay
Working with Guys hospital in London, TeraView has shown how effective terahertz waves can be as an intra-operative tool during breast cancer surgery. This circumvents the biopsy lab and allows the surgeon to analyze removed tissue, and then carry out further removals if required. Results indicate a specificity of 88-90% and a sensitivity of circa 72%.
Further in-vivo trials have been undertaken, that placed the terahertz probe within the incision to check for any remaining cancer tissue. TeraView has received approval by the Medicines and Healthcare products Regulatory Agency (MHRA) to conduct these trials and use Terahertz Pulsed Imaging (TPI™) for (bio)medical research.
This information has been sourced, reviewed and adapted from materials provided by TeraView Ltd.
For more information on this source, please visit TeraView Ltd.