Background: The middle cerebral artery (MCA) has an individually varied anatomical type and course. Age and sex variability of MCA have not been completely defined. The aim was to define the range of normal values of widths and lengths of particular MCA segments, define age and sex variability, and compare the compatibility of MCA measurements of digital subtraction angiography (DSA) and MR angiography (MRA).
Material and Methods: The study was a retrospective evaluation of 114 examinations of cerebral vessels (88 DSA, 26 MRA). It included patients in whom the angiographic examinations did not show any pathological lesions. DSA was carried out using a routine protocol applied to examinations of cerebral arteries; MRA was performed with a 1.5 T scanner and the time of flight (TOF) method using the fast gradient echo sequence with RF spoiler- multivolume RF-FAST. The diameter measurements of the internal carotid arteries (ICA) and segments of the MCA were based on DSA and MRA; the study also included the lengths of MCA segments from the origin to the first first ramification and from the origin to the bifurcation.
Results: The width and length ranges of particular MCA segments in a group of healthy patients were defined by DSA and MRA. The diameters of ICA and MCA and its upper branch are age and sex dependent, being wider in men than in women and increasing with age.
Conclusions: MR angiography is a fully reliable method allowing assessment of middle artery morphology, but precise evaluation of the widths of the artery and arterial branches with MRA should include the source images of the vascular sequence.

Keywords: Adolescent, Angiography, Digital Subtraction, Magnetic Resonance Angiography, Middle Cerebral Artery - physiology, Reference Values, Regional Blood Flow, Sex Factors