Quantifying epithelial migration in vivo

I am an academic ear specialist and a basic user of Image J. I’m seeking advice on how to analyze endoscopic images of the eardrum and ear canal (or surgically created cavities after a procedure called a mastoidectomy), to try to quantify fine epithelial ridges that form as a consequence of the known epithelial migration pattern. Epithelial migration occurs more or less in a radial direction, originating near the center of the eardrum and extending out into the ear canal, where it continues towards the meatus, where exfoliation occurs as ear wax.
When the epithelium is dry or partly obstructed, fine ridges form and are well demonstrated in a surgical cavity of the left mastoid bone (Figure 1). To highlight these ridges and to start the process of quantification, I used the convolve filter, which seemed to work the best out of the options given in the basic downloaded version of Image J (Figure 2).
My questions are: 1) how do I best select out the ridges (which in this case are primarily vertical in orientation) and separate them from the background artifact of light reflection and blood vessels or other anatomic features and then quantify them in terms of number and length? 2) Based on their orientation, how can I draw a superimposed line, perpendicular to the orientation of the ridges, to estimate the direction of the epithelial migration? I realize I am making an assumption there, but it is well founded.
Thank you in advance for any recommendations!
Bob Jyung