BACKGROUND/AIMS

To determine a reference data set for stiffness values of normal lacrimal gland using shear wave elastography and to evaluate the interobserver variability of these measurements.

MATERIAL and METHODS

A total of 50 participants (bilaterally 100 glands) comprising 25 females and 25 males, aged between 19 and 58 years, were included in this prospective study. For each participant, we evaluated both lacrimal glands using grayscale and shear wave elastography, and the relationships with sex, age, and body mass index were determined. All lacrimal glands were evaluated by 2 independent observers blinded to each other.

RESULTS

The mean stiffness values of lacrimal glands for the 2 observers were 6.17±2.94 kPa and 6.00±3.10 kPa, respectively. In terms of stiffness values, there were no significant differences between the left and right lacrimal glands and between sexes (p>.05). Age exhibited a weak correlation with stiffness values (r=0.280, p=.005; r=0.284, p=.004). The intraclass correlation coefficient for the interobserver variability of the shear wave elastography measurements was 0.948 (95% confidence interval: 0.924-0.965).

CONCLUSION

The lacrimal gland can be quantitatively evaluated using shear wave elastography. Normal shear wave elastography values for the lacrimal gland in the healthy population included in this study were estimated to be 6.17±2.94 kPa. Operator dependency of this method is low, and interobserver compliance is high. The standard stiffness values of the normal lacrimal gland obtained using shear wave elastography in this study may be used as reference data to distinguish the healthy tissues from the pathological tissues.

Keywords: Lacrimal gland, elastography, interobserver variability, ultrasound imaging