Latest techniques in head and neck CT angiography

Abstract

Continuous evolution of multi row CT is increasingly making CT angiography a viable imaging modality for assessment of the supraaortic and intracranial vessels as an anatomically and functionally coherent vascular system. Extended non-invasive examinations with reduced contrast volume have become feasible with the availability of 16 and 64 row MDCT scanners. Prerequisites to obtain high resolution CT angiographies of the head and neck vessels with superior detail include the administration of low contrast volume, high contrast density (400 mg I/ml) contrast media, adequate timing and data acquisition, optimal flow rate (4 ml/s) and saline flushing. Non-invasiveness, delineation of vessel calcification, virtual independence from hemodynamic conditions, and the ability to provide quantification without needing to correct for magnification are all attributes that favour CT angiography over digital subtraction angiography and to some extent even magnetic resonance angiography as an alternative non-invasive technique. CT angiography is established as a modality of choice for the assessment of patients with acute stroke and chronic steno-occlusive disease. CT angiography may indicate the presence of extra-or intracranial

Carotid and vertebral artery dissections: clinical aspects, imaging features and endovascular treatment

“…Axial source images provide excellent visualisation of the craniocervical arteries as a consequence of the contrast difference between the enhanced arterial lumen and the surrounding structures. Postprocessing of the source data as MIPs or curved multiplanar reformats MPR produces images that closely resemble those obtained with intraarterial angiography, and voxel-rendering techniques allow a 3D display of the vessels and surrounding soft tissues [78]. CTA of ICA dissections has shown excellent agreement with arterial angiography [79].…”

A Comparison of Radiation Exposure between Diagnostic CTA and DSA Examinations of Cerebral and Cervicocerebral Vessels

“…[1][2][3] Multidetector CTA also permits rapid scanning with a narrow section thickness and isotropic voxel data with superior resolution in the z-axis to evaluate cerebral and cervical vascular pathologies. 1,4 An important principle guiding the diagnostic use of radiation is to keep the radiation exposure as low as reasonably achievable. Because DSA and CTA have very different irradiation geometries and the radiation exposure is reported in different quantities, the effective dose is a useful means of comparing the stochastic risks, such as cancer induction, malignant disease or heritable effects caused by an exposure to ionization radiation.…”

Application of CT for the Study of Pathology of the Jaws

“…Multi-detector CT scanning could improve the performance of CT angiograms and dynamic contrast and maneuver imaging. 4,5 Multi-detector CT angiography is used to delineate the blood vessels ( Fig. 1) and to provide information about the exact location of neoplasms, lymphadenopathy, and their vascular infiltration or spread.…”