ICC to test an algorithm


I work with MRI data, we have collected two sets of T1 data of 1 subject. One data set is the subject was scanned 10 times repeatedly in a stationary head position. The other data set, is the patient with 12 positions, looking up/down/left forward, diagonal etc.

The goal is to evaluate the consistency or reliability of the software algorithm to calculate brain volumes, but I do not know what test(s) to use, perhaps ANOVA or ICC measurements?The issue is, there are no raters, it's the same algorithm applied across the data sets. Also, the stationary data set has less variance than the rotations one, so could I use the mean volumes from stationary data as a reference point? and plot percentage differences between each rotated scan with that reference mean?

Thank you for your time!