Table 4. Ethnic variation in the pterion position with respect to external and internal landmarks as reported by diverse authors.

Study	Ethnicity	Distance of the center of the pterion (mm)
			Zygomatic arch	Frontozygomatic suture	Optic canal	Sphenoid ridge
Oguz et al. (2004) [18]	Turkish	Right	40.5±3.9	33.0±4	43.9±4	14±3.3
		Left	38.5±2.5	34.4±3.9	43.6±4	14.8±3.2
Apinhasmit et al. (2011) [13]	Thailand		38.48±4.38	31.12±4.89	38.94±3.76	11.70±4.83
Present study	India
	Male	Right	38.25±4.11	29.90±4.39	43.1±2.58	10.7±2.7
		Left	36.78±3.53	27.81±4.57	43.3±3.57	10.8±3.15
	Female	Right	36.33±2.74	26.94±2.71	41.8±4.34	10.1±2.39
		Left	35.94±3.32	27.11±5.02	41.5±4.41	10.4±1.93
Ilknur et al. (2009) [20]	Anatolia	Right	38±4	35±5	-	-
		Left	39±4	35±5	-	-
Mwachaka et al. (2008) [11]	Kenyan	Right	38.88±3.49	30.34±4.30	-	-
		Left	38.24±3.47	30.35±3.40	-	-
Adejuwon et al. (2013) [12]	Nigerian	Right	39.1±0.58	31.52±0.67	-	-
		Left	38.77±0.63	30.82±0.80	-	-
		Male	39.74±0.50	31.87±0.64	-	-
		Female	37.95±0.65	30.35±0.83	-	-

Values are presented as mean±SD.