Ultrasound elastographic evaluation of the median nerve in pregnant women with carpal tunnel syndrome

OBJECTIVE

To evaluate the median nerve (MN) in pregnant women with carpal tunnel syndrome (CTS) by using ultrasound elastography.

PATIENTS AND METHODS

30 wrists of 20 pregnant women with CTS and 25 wrists of 14 healthy control pregnant women were evaluated by ultrasound and ultrasound elastography (UE). The MN in the patients' wrist was imaged to measure the cross-sectional area and longitudinally to calculate the elasticity value (EV) at four different locations (proximal carpal tunnel (CT) at the level of the pisiform, distal CT at the level of the hamate, middle of the CT and forearm at one centimeter above the CT). Clinical classification was performed according to a historic and objective scale of CTS. In the healthy pregnant women and pregnant women with CTS, MN area and EV were analyzed statistically by comparing with parity and clinical grade.

RESULTS

There was a statistically significant difference for MN area between the patient and control groups (p = 0.001). A positive relationship was found between parity in pregnancy and clinical grade of the CTS (p = 0.035, Pearson's correlation coefficient = 0.386). Although MN elasticity for both groups was nearly the same in the proximal region of the CT, these values were decreased in the middle of the CT. MN elasticity values were smaller in the distal region of CT, and it was statistically significant in pregnant women with CTS (p = 0.02).

CONCLUSIONS

Ultrasound elastography, which is a non-invasive, inexpensive and a favorable diagnosis technique, may be useful in the diagnosis of CTS, especially in conditions in which an invasive procedure would be problem, as in pregnancy.