Application of subtraction technique in 64-slice spiral CT angiography for cervical and cranial artery

Objective:To study the ability and advantages of subtraction technique in 64-slice spiral CT angiography for cervical and cranial artery.Methods:Twenty-five patients suspicious of intra-and extra-cranial artery disease were obtained by 64-slice spiral CT angiography.A special head holder was used during the scanning.All the data obtained in scan was transferred to workstation and processed with subtraction technique to get the artery images.Fifteen cases was processed with routine CTA and 8 cases undertook DSA examination.Subtraction CTA and routine CTA were compared in speed,image quality,and then both were compared with the DSA images.Results:The common carotid arteries,inter-carotid arteries,vertebral arteries and their primary branches were displayed in all 25 cases.Arteries were displayed well in 17 cases because vertebra and skulls were all subtracted;8 cases the arteries were displayed worse because light shift of head or swallow.Subtraction CTA took 4.3 minutes in obtaining images while routine CTA took 24.3 minutes.There is no obvious difference in image quality for cervical artery while subtraction CTA was better than routine CTA in displaying intracranial arterial trunk and their branches,which had the same result obtained in DSA.Conclusion:Subtraction technique in 64-slice spiral CT angiography for cervical and cranial artery is deserved to be popularized since its time-and labor-saving,its convenience and its good image quality.