Figure 1. Endoscopic views of the lesions lacking detectable vasculatures
Top left and right images demonstrate a left sided vocal fold granuloma in spectra B (S-B) and spectra A (S-A) modes, respectively (patient #38 in the survey). The surface of the lesion is covered with a blanket of fibrin-like material, showing no identifiable vascularization. Bottom images show S-B and S-A view of a keratotic leukoplakia with low-grade dysplasia on the left vocal cord (patient #39), vascular patterns are obscured by the umbrella effect of the plaque.
Figure 2. Longitudinal vascular pattern
Side by side view of W and S-B images of the vocal cords in the patient #22. Note the meandering tortuous vessels on a polyp on the left vocal cord (asterisk), and a small polyp with ectatic vessels running parallel to the right vocal cord (arrows). These changes are classified as longitudinal.
Figure 3. Perpendicular vascular pattern
Side by side view of W and S-A images of the vocal cords in the patient #35. The right cord is thick, with an irregular surface, and associated with subglottic edema; diagnosed as high-grade dysplasia. S-A image shows perpendicular vessel loops (arrows) as yellow-greyish spots, indicating the presence of a malignant pathology. On the W image, the vascular pattern is unclear.