Helical (spiral) CT in neuroradiologic diagnosis.

The use of helical (spiral) CT in the evaluation of the head and neck is discussed in this article. Neuroradiologic applications of this modality include evaluation of the carotid bifurcation, intracranial aneurysms, arteriovenous malformations, craniofacial imaging, and laryngeal anatomy. Comparison of helical (spiral) CT with conventional CT, MR angiography, and conventional angiography is provided where applicable. Advantages and disadvantages of this versatile and rapidly evolving technique also are discussed.