How to select the right probe for you.

We recommend the MC4-2R20S-3 20mm radius, 2-4Mhz probe for adults and children older than 6 years. This probe has a good curvature to make full contact under the chin and sits comfortably between jaw and neck. 2MHz gives good penetration through the muscle fibres providing a bright surface contour, even when the tongue makes contact with the palate. The higher 4MHz frequency can be set for smaller participants where the distance from probe surface to palate is less. The higher frequency produces a less grainy subjective image. Graininess does not affect the accuracy of the tongue contour estimation. This is our recommended default probe.

Younger children or children with craniofacial disorders may not have enough space between the jaw and neck to fit the 20mm radius probe. In such cases the MC10-5R10S-3 microconvex 10mm radius 5-10MHz probe may be more appropriate.  The higher minimum frequency of 5MHz results in shorter penetration depth making it unsuitable for imaging adult tongue contours. The microconvex also has a very tight (10mm) curvature. If it is not pressed into the chin with plenty of gel then loss of probe contact at the periphery of the field of view is likely and contour estimation will be poor as a result.

Other probe options include the C5-2R60S-3, a 60mm radius 2-5MHz probe. This is too large for speech research, as it will extend beyond the chin and the ultrasound beams are relatively vertical compared to the previously discussed probes, resulting in tongue blade being concealed by the mandible shadow. It does however provide a clear view of the hyoid and mandible.

There is also the MC8-4R20S-3 probe. A 20mm radius with slightly smaller field of view than the MC4-2R20S-3 probe and higher frequency range of 4-8MHz.  We do not recommend this probe.

Linear probes are available but currently AAA cannot record data from them. We plan to revise AAA soon to permit recording and synchronisation of linear probes with speech audio and to display the image.