Fig 1.
Visualization of the imaging data analysis method.
First, pre-operative CBCT scans are used to trace the lateral wall of the cochlea (A). Then, post-operative CBCT scans are used to trace the electrode array by marking the position of each electrode contact (B). Finally, the two traces are combined to obtain a reconstruction of the implanted cochlea that can be used to derive anatomical and positional parameters (C).
Table 1.
Overview of the demographic data, anatomic measurement data and speech recognition data of the study cohort in groups according to electrode array.
Fig 2.
Histograms of cochlear length measurements with fitted normal distributions: One-turn length (1TL, blue), two-turn length (2-TL, red) and total cochlear duct length (CDL, gray).
Fig 3.
Distributions of cochlear coverage (left), insertion depth (center), and insertion angle (right) across the entire cohort (top row) and across sub-populations with different electrode arrays (bottom panels).
Fig 4.
Scatter plots of FMWT scores (top row), HSM sentence test scores in noise (center row) and ΔFMWT (bottom row) over cochlear coverage (left column) and insertion angle (right column).
Solid lines, r-, and p-values show the results of linear regression modeling. Different symbols correspond to different electrode arrays.
Fig 5.
Box plot of FMWT scores (left) and HSM sentence test scores in noise (right) for groups of subjects based on cochlear coverage quintiles.
Colored areas in the diagram in the bottom right corner correspond to the ranges of cochlear coverage of the five quintiles in an average cochlea. The whiskers indicate the minimum and maximum value in each group. (*: p<0.05; **: p<0.01; ***: p<0.001).
Fig 6.
Box plot of FMWT scores (left) and HSM sentence test scores in noise (right) for groups of subjects based on insertion angle quadrants.
Colored areas in the diagram in the bottom right corner correspond to the ranges of insertion angle of the five groups. The whiskers indicate the minimum and maximum value in each group. (*: p<0.05; **: p<0.01; ***: p<0.001).
Fig 7.
Box plot of ΔFMWT for groups of subjects based on cochlear coverage quintiles (left side) and for groups of subjects based on insertion angle quadrants (right side).
Colored areas in the diagrams correspond to the ranges of cochlear coverage of the five quintiles, and the ranges of insertion angle of the five groups, respectively. The whiskers indicate the minimum and maximum value in each group. (*: p<0.05; **: p<0.01; ***: p<0.001).
Table 2.
Cohort sizes for the different statistical analyses.
Table 3.
Results of the analysis in sub-groups with extracochlear and deactivated electrode contacts.