Assessment of Low Versus Standard kVp Settings in Cerebral CT Angiography for the Optimization of Contrast Medium
Recent advances in Computed Tomography (CT) have greatly increased the clinical applications of CT, especially since the advent of Multi-Detectors Row CT (MDCT) technology. CT Angiography (CTA) has been advocated for pre-operative evaluation of cerebral blood vessels pathologies and their relationship with the main branches. Moreover, it is crucial to detect other vascular morbidities, such as arterial occlusive diseases. CTA allows the proper visualization of main vascular structures and has several advantages: minimal invasiveness, with a lower complication rate than that of angiography; generation of high spatial resolution images; availability of multi planar reconstructions and 3D reconstructions; and short examination time, allowing extended scan ranges. Consequently, potential benefits of lower-kV scanning at contrastenhanced CT include reduced radiation dose with similar contrast-tonoise ratio and reduced effective dose. Recently, lower-kV imaging has been shown to result in improved conspicuity of cerebral blood vessels lesions and dominancy in different patients. In addition to the radiation dose savings, lower-kV scanning may be beneficial, for diagnostic purposes in patients with poor i.e., access or renal impairment in whom a smaller contrast dose or slower infusion rate may be necessary or in patients in whom subtle attenuation differences may be diagnostically important. Low-tube-voltage-setting protocol combined with low contrast agent volume, by using new MDCT scanners represents a feasible diagnostic tool to significantly reduce the radiation dose delivered to patients and to preserve renal function, while also maintaining adequate diagnostic quality images. Since the introduction of MDCT, CTA has become a standard imaging tool for the evaluation of diseases affecting the carotid arteries and their branches. Result of the present study was as follow: There was a higher significant difference in all study cases group when compared with the control group (2). The dose of contrast medium and radiation given to the patient to perform a MDCT scan on the cerebral vascular system by using the low kilovolt technology was reduced by 38% and 40%, respectively, while also maintaining adequate diagnostic quality images.