Sir,

Many thanks to Ozkan et al. [1] for their comments on our article “Acoustic radiation force impulse elastography for detection of renal damage in children” [2]. Their criticisms regarding the limitations caused by the image acquisition technique have been reported previously [3–5].

We attempted to design the study protocol so as to reduce these known limitations of elastography. We obtained 15 measurements in total, 5 measurements from each of the 3 segments, from each kidney. Furthermore, we performed evaluations both subjectively and quantitatively.

Although we did not compare measured values among different segments, these comparisons can be done in the normal kidneys of the control group. Because kidney damage may be global or segmental, we performed elastographic measurements both globally‒subjectively, and quantitatively by segment.

To decrease inaccuracy related to anisotropy and to compression exerted via the transducer, we performed a large number of measurements. We also calculated inter- and intra-observer variability. Elastography is similar to ultrasound in that it is both patient- and operator-dependent, an issue we discussed in our paper. We made efforts to decrease these constraints.

We agree that further studies are needed, in particular to determine optimum cut-off values for diagnostic categories.