Using the Middle Turbinate to Protect the Skull Base in Endoscopic Transsphenoidal Surgery: A Cadaver Study

Abstract

Objectives Inadvertent intracranial injury from nasogastric tube (NGT) placement is a described and potentially fatal complication following endoscopic transsphenoidal hypophysectomy (TSH). This cadaver study assessed the role of middle turbinate (MT) preservation and medialization in preventing accidental skull base injury from NGT insertion after TSH. Methods: Standard approach for TSH was performed on 3 human cadavers. MTs were placed into neutral position (MTN), then medialized via suture pexy to the septum (MTP), and subsequently resected (MTR). After each stage, 3 blinded individuals passed a 10 F Dobhoff and a 16 F NGT on each side of each cadaver (5 passes per side). Using endoscopic visualization, each pass was scored by a blinded reviewer based on the first contact point of the tube (0 = nasopharynx, 1 = inferior sphenoid face, 2 = sphenoid sinus), with higher scores suggestive of increased risk of intracranial injury. Results: There were 270 Dobhoff and 270 NGT passes scored. Data was divided into 3 groups based on presence and position of the MT. Significant differences were demonstrated between all three groups [one-way ANOVA: Dobhoff F(2,267) = 6.981, p = 0.001], [NGT F(2,267) = 17.582, p < 0.001]. There were significant differences between means for MTN versus MTP groups [Dobhoff (0.43 vs 0.22, p = 0.007), NGT (0.73 vs 0.28, p < 0.001)] and MTP versus MTR groups [Dobhoff (0.22 vs 0.55, p < 0.001), NGT (0.28 vs 0.81, p < 0.001)], indicating that the presence and position of the MT can significantly affect the accessibility of the sphenoid sinus interior after TSH. There was a trend toward lower means in the MTN group compared to the MTR group. Conclusion: MT preservation and deliberate medialization against the septum may reduce risk of inadvertent intracranial NGT injury in postop TSH patients. This simple maneuver should be considered in all routine TSH procedures.