Aim The purpose of the present research was to assess various factors which affect temporal hollowing after pterional craniotomy procedure. Methodology A retrospective study of patients who underwent pterional craniotomy was conducted. Inclusion criteria included older than 18 years, having undergone unilateral pterional craniotomy, and with no craniofacial anomaly or temporal defect. Volumes of bone, temporalis muscle, and extratemporalis layer were calculated. Results A total of 51 patients were included. Bone volumes of surgical and nonsurgical sites were 219.12 + 23.02 cm3, and 228.39 + 22.76 cm3, respectively (p = 0.04). Difference of bony volume was 9.10 cm3 (3.99%). Volumes of temporalis muscle in surgical and nonsurgical sites were 12.86 + 3.95 cm3, and 18.10 + 6.08 cm3, respectively (p < 0.005). Difference of muscle volume was 5.08 cm3 (28.32%). Volume of extratemporalis soft tissue in surgical and nonsurgical sites were 11.99 + 5.70 cm3, and 17.31 + 7.76 cm3, respectively (p < 0.005). Difference of soft tissue volume was 5.56 cm3 (31.68%). Conclusion Hollowing after pterional craniotomy is an unavoidable result. Bone, temporalis muscle, and soft tissues are combined etiologies. Volume of temporal area reduction was 19.74 cm3. Immediate reconstruction is recommended and volume of reconstruction is calculated from preoperative imaging.

pterional craniotomy, temporal hollowing, aetiology, bone volume