Table 2. Overall Sensitivities and Comparison of the Sensitivities of CTP and 4-Point Scoring Systems of CTA in Patients with and without Open Skull Defect.

		Overall Sensitivity	Open Skull Defect (-)	Open Skull Defect (+)	P
CTA (%)
	ICV-SPV	89.5	100	80.4	0.003
	A20-V60	82.6	95.0	71.7	0.005
	A60-V60	67.4	77.5	58.7	0.063
CTP (%)		93.3	100	86.5	0.019

P values refer to statistically significant difference between the sensitivities of CTA and CTP of the open skull defect absence (−) and presence (+) group. A20-V60 = 4-point scoring system that evaluate vessel opacification on arterial phase for arteries and venous phase for veins, A60-V60 = 4-point scoring system that evaluate vessel opacification on venous phase for both arteries and veins, CTA = computed tomography angiography, CTP = computed tomography perfusion, ICV-SPV = 4-point scoring system that evaluate vessel opacification on venous phase for internal cerebral vein and superior petrosal vein