Figure 4: Scanning electron microscopy images of rabbit nasal septal cartilage specimens. Images (a), (b), and (c) were taken at 2000 magnification. (a) Control specimens show organized, layered, thick collagen fibers. (b) EMR-treated (6 V, 5 mins) specimens at the positive electrode needle insertion site (anode). (c) EMR-treated specimens (6 V, 5 mins) at the negative electrode needle insertion site (cathode). EMR-treated cartilage obtained from the needle electrodes insertion sites shows irregularly arranged collagen fibers that vary in thickness. The specimens at the negative needle electrode show more loosely connected, damaged, irregular fibers compared with those at the positive needle electrode.