Associations Between Post-tonsillectomy Hemorrhage and Anatomical Subsites of the Tonsillar Fossa

ObjectiveThis study presents a novel classification of the anatomical subsites of the tonsillar fossa and discusses their associations with post-tonsillectomy hemorrhage (PTH) after extracapsular tonsillectomy.Materials and MethodsCoblation tonsillectomy was performed on three adult cadavers and the anatomical subsites of the tonsillar fossa based on the distribution of the tonsillar feeding artery: the upper pole (subsite A), most of the tonsil body (subsite B), the inferior tonsil body (subsite C), and components of the lower pole (subsites D and E). Extracapsular tonsillectomy was prospectively performed using various surgical techniques and PTH was evaluated.ResultsA cadaveric study revealed that the intra- and extra-capsular vessel topographies were essentially identical. Although the demarcation lines varied either up or down by a few millimeters, the arterial vascular network was particularly dense at subsites D and E, and the vessel diameter at these subsites was significantly greater than at subsite C and also (especially) at subsite E. Of 680 patients who underwent tonsillectomy, PTH developed early in 13 (31.7%) and late in 28 (68.3%). Surgical interventions were required by 29/41 patients (70.7%). Subsites D and E were the most common subsites of late PTH and PTH that required intervention. Such intervention was rarely necessary when PTH developed at subsite A or B.ConclusionsThe new classification of the anatomical subsites of the tonsillar fossa aids inexperienced surgeons and provides an anatomical rationale for variation in surgical technique that minimizes vascular injury, thus improving safety.