Superficial Temporal Artery Biopsy Incision Optimization: An Anatomical Study

Purpose: To describe the course of the superficial temporal artery (STA) and identify the optimal location for temporal artery biopsy when a pulse cannot be reliably palpated. Methods: In this anatomical study, the arterial systems of 12 fresh adult cadaver heads were filled with red neoprene latex to highlight the STA. Coronal incisions starting at the root of the auricular helix and extended 80 mm superiorly were made bilaterally. The primary outcome was the probability of the STA being encountered at each location on a standardized, superimposed 50 × 50 mm grid. Secondary outcomes included degree of declination from the incision line, distance at which the vessel crossed the incision, presence of frontal/parietal bifurcation, presence of branches, visibility of the temporal branch of the facial nerve, and vessel caliber. Means, standard deviations, and ranges were used to describe the data. Results: In all specimens analyzed, the STA crossed the coronal incision line within 45 mm of the helix root. The STA was found within the same 5 × 5 mm location, 10 to 15 mm cranial to the root of the helix, and 5 to 10 mm anterior to the incision in 68.4% of specimens. In the remaining specimens, a portion of the STA was found within 7 mm of this location. Conclusion: Especially in cases where the STA is nonpalpable, care must be taken to avoid iatrogenic injury to the facial nerve during temporal artery biopsy. Surgeons should recognize that the STA can be reliably encountered with an incision beginning 5 mm anterior and 5 mm cranial to the helix root, carried 40 mm in the posterior and cranial direction, 30 degrees declined from the coronal plane.