The “Lake Road Sign”: Another Way to Track the Sulcus Vocalis

Figure. A: Direct laryngoscopy utilizinga chip-on-the-tip ENF-VT videoscope (Olympus, Inc.;Hamburg,Germany)showsa lakeroadsignvessel (whitearrow) on the left vocal fold without the use of NBI technology. B: Probing the pocket with a spatula under direct laryngoscopy demonstrates the presence of a left vocal fold sulcus vocalis. C: Illustration shows the similarity of the endoscopy images to roads skirting lakes. The recent emergence of the chip-onthe-tip flexible endoscope allows careful observation of subepithelial vascularization patterns. Recent literature has focused primarily on early detection of malignant lesions of the vocal folds and their differential diagnosi s with benign laryngeal papillomatosis. This effort is an attempt to guide-s-if not avoid-vocal fold biopsy, creating a paradigm shift from biopsy diagnosis to "photo diagnosis"!" Nevertheless, this trend could also be beneficial for the diagnosis of benign lesions, such as sulcus vocalis. A sulcus vocalis is characterized by the disappearance of the submucosal matri x, leading to an epithelial invagination associated with various degrees of adherence to the different layers of the underlying lamina propria. This "pocketing" of the mucosa forces the afferent vessels, progressing in the matrix , to make a detour. The afferent vessel that is perpendicular to the gap will usually split into two vessels, skirting the gap edges. We called this a "lake road sign:' referring to the same phenomenon that characterizes roads hitting lakes and skirting them (figure). Hypothetically, the lake road sign could be applicable to mucosal bridges, as well, although this has never been seen by the authors. With the new flexible endoscopy image-enhancing technologies that are available, this sign is much easier to notice than it was before. Perhaps narrow-band imaging (NBI) could add accuracy to the detection of lake road signs; however, this is still unknown and should be investigated in the future. Likewise, future studies should compare the specificity and sensitivity for sulcus diagnosis with the lake road sign and compare it to stroboscopy results.