Fig. 2
From: Pre- and post-operative imaging of cochlear implants: a pictorial review
Evaluation of cochlear duct length (CDL) using the formula CDL = 4.16A–2.7 and a 3D segmentation (dashed line). HRCT paracoronal image on the left shows distance A (arrow) from the center of the round window to the far most extension of the basal turn, which measures 9.2 mm. According to the formula the cochlea duct has a length of 35.6 mm. The dashed line in the HRCT paracoronal image and the HRCT paraaxial image on the right shows the 3D segmented cochlear duct which measures 35.9 mm