The Horizon Sign and Frontal Bar: Two Topographic Landmarks to Confirm Endoscopic Frontal Sinusotomy. (April 2019)

• Record Type: Journal Article
• Authors: Walgama, Evan S.; Thamboo, Andrew; Tangbumrungtham, Navarat; Ayoub, Noel; Patel, Zara M.; Nayak, Jayakar V.
• Is Part Of: Otolaryngology--head and neck surgery. Volume 160:Number 4(2019)
• Page Start: 740
• Page End: 743
• Publication Date: 2019-04
• Subjects: frontal sinus -- frontal sinusotomy -- endoscopic sinus surgery -- ESS -- horizon sign -- frontal bar -- posterior table -- Draf -- landmark; Head -- Surgery -- Periodicals; Neck -- Surgery -- Periodicals; Otolaryngology -- Periodicals; 617.51
• DOI: 10.1177/0194599818825472
• Languages: English
• ISSNs: 0194-5998

Abstract

Confirming a thorough dissection of the frontal sinus during endoscopic sinus surgery can be challenging, and some surgeons would benefit from reliable topographic landmark identification to ensure completion of this sinus dissection. We defined (1) the "horizon sign" as the curvilinear shadow of the posterior table cast superiorly upon the anterior table of the frontal sinus at the acute angle of their meeting point and (2) the "frontal bar" as a sagittal septation at the union of the anterior/posterior tables. A cadaveric study, followed by an intraoperative consecutive case series, was performed to evaluate these 2 landmarks as indicators of complete dissection. The horizon sign was extremely reliable, identified in 100% of cadaveric frontal sinuses and intraoperative frontal sinuses. The frontal bar was present in only 67% of frontal sinuses by computed tomography. In live patients, the sensitivity and specificity of the frontal bar were 62% and 95%, respectively.