The Relationship between the Frontal Branch of the Superficial Temporal Artery and the Temporal Hairline in Bicoronal Incisions: Cadaveric and Clinical Study.

[INTRODUCTION] Classic bicoronal skin incisions for bifrontal craniotomy are usually performed near the course of the superficial temporal artery (STA). This frequently results in injuries to the frontal branch (fSTA) or even the STA's main trunk. We investigate the usual course of the fSTA and evaluate a previously proposed modification to bicoronal scalp incisions for its rate of STA preservation.

[MATERIALS AND METHODS] Sixteen sides of cadaveric heads were dissected. We investigated the location of the fSTA in relation to the temporal peak of the hairline. We also performed a retrospective study of 19 patients with cerebral aneurysms who underwent microsurgery using the modified bicoronal incision. The patients were treated at our facility between June 2017 and Jan 2022. Patients' data were retrospectively reviewed and evaluated for postoperative STA preservation.

[RESULTS] The majority of fSTAs (68.75%) passed through and just anterior to the temporal peak. The average distances between the fSTA and the temporal peak from the anterior and posterior aspects were 0.44 (0.2-0.7) cm and 0.52 (0.3-0.8) cm. The mean distance between the STA bifurcation and the zygomatic root was 3 cm. Using the modified bicoronal scalp incision, the right fSTA of 14/19 (73.7%) patients and the left fSTA of 16/19 (84.2%) patients were preserved in the scalp flap.

[CONCLUSION] The most anterior part of the fSTA was located very close to the temporal peak of the hairline. The modified bicoronal skin incision for bifrontal craniotomy and modified transbasal craniotomy was an effective means of STA preservation.