The vallecular line: an objective measure in evaluating the base of the tongue and vallecular cancers for transoral robotic surgery.
OBJECTIVE
We hypothesized that the degree of the exophytic nature of the base of the tongue and vallecular cancers (BOTs) impacts the feasibility of transoral resection. The growth pattern of these cancers can be measured by the vallecular line (VL), which is the distance between the hyoid bone and the vallecular tip.


MATERIALS AND METHODS
The normal VL was measured by 3 radiologists on 50 magnetic resonance imaging scans. The VL was then measured on magnetic resonance imaging scans of patients with BOT cancers.


RESULTS
The mean VL was 8.2 mm (6.4-10 mm) in the healthy patients. The mean VL of the patients with predominantly exophytic BOT cancer was 22.7 mm (20.6-24.8 mm). Postoperative images of these patients demonstrate minimal loss of the native tongue after transoral resection.


CONCLUSIONS
The VL is a valuable objective measurement of the exophytic nature of BOT cancers. Predominantly exophytic BOT cancers are deemed more amenable for successful and functional transoral surgical resection.