Medical Applications

Millimetre wave radiation interacts with the human body down to a depth of around half a millimetre into the skin at 100 GHz; less than this depth at higher frequencies, with greater penetration at lower frequencies. Interaction is exclusively with the skin, including the first layers of living tissue. It is therefore the ideal probe for the largest organ of the human body.

Spatial resolutions of measurements are down to half a wavelength in the skin, so range from 0.1 mm to 5 mm.

The medical applications of millimetre wave sensing technology are relatively undeveloped, mainly due to the subtlety of signatures and the absence of commercially available systems that generate high quality calibrated data. Likely applications are those associated with the early diagnosis of: skin cancers, skin moles, Raynaud's disease, psoriasis, scleroderma, eczema and diabetic (foot and leg) ulcers.

Moving to lower frequencies around 10 GHz will enable penetration to ~2 mm enabling signatures to be measured associated with circulatory disorders.

Potentially these measurements could be made of the whole of the human body in a period of seconds, enabling a new type of whole-body screening. Periodic measurements may identify precursors of developing disorders, in or just under the skin.

Millimetre wave diagnostics used on human skin could complement existing techniques (ultrasound, CT, MRI, PET) that are used to scan neighbouring regions of the body.

Currently, no effective millimetre wave medical diagnostic systems exist, but a diversity of highly mature devices and subsystems exist from which a diagnostic could be developed.

Visibility through bandages: Assessing the condition of healing wounds through bandages is another potential area of exploitation; bandages are transparent in the millimetre wave band. In many cases (typically for burn victims) the removal of bandages for inspection is painful. This technology offers a potential less disruptive route to a rapid assessment.