CTS Ultrasound measurements
16 May 2015 - 6:46am
Hi,
I have just did an ultrasound of my hand/wrist and the Median nerve area is 0.107 cm2. Could it be Carpal tunnel ? I was reading on websites that anything above 0.09 cm2 is highly predictable of CTS ...!!! I have to wait until next week to see my doctor, I was wondering if anybody had any clue.
Thanks a lot
It depends on the scanner, transducer, how they measured it, and who was doing it. The upper limit of normal in different studies varies from 9 to 13 mmsq (0.09 to 0.13 cm2) so you are dependent on whoever did the scan to tell you whether that measurement is above their local limit for normality. The greater the margin by which your measurement exceeds the local normal range the more likely it is to be CTS but there are other conditions which can cause nerve enlargement. It's helpful if the nerve at the wrist is compared with a little further up the arm, where it should be normal in CTS. Some units do this formally and give you a ratio measurment of forearm to wrist cross sectional area. The normal values are probably also influenced somewhat by age and height.
All test results are pretty irrelevant unless you have symptoms and signs consistent with the diagnosis in question. Running through the questionnaire on the website here will give you an indication of whether you have symptoms consistent with CTS. JB