In vivo localization of brain sulci by arteriography: a stereotactic anatomoradiological study

The authors studied the course of the cortical arteries using the Talairach stereotactic system (orthogonal 4.8 m teleradiography, with rigid fixation of the skull in the stereotactic frame) in both anatomical specimens and normal bilateral carotid angiographies of epileptic patients. Anatomoradiological correlations between arterial patterns and underlying brain surface were identified by detailed 3-dimensional analysis of brain-skull preparations, where gyri and injected arteries were dissected progressively with stereotactic X-ray and photographic pictures taken at each step. The vascular landmarks so identified were studied in stereoscopic arteriographies that give a direct visualization of the spatial relationships of the arterial tree moulding the cortical surface thus allowing the recognition of the localization of the principal gyri and sulci. The latter were drawn on stereotactic diagrams. The basic sulcal pattern as shown by the arteries is strikingly symmetrical in both hemispheres of the same individual, in spite of variability in branching of the arterial tree. The disposition of the vascular landmarks in the retroinsular region reflects the left-right asymmetry of the planum temporale that can be recognized in vivo. This can give a clue to the study of anatomofunctional correlations with regard to speech dominance. A limited first series studied in this respect strongly suggests a close relationship between anatomical and functional asymmetry of the human cerebral hemispheres. Generally speaking, the authors feel that 3- dimensional, anatomical interpretation of angiography permits a direct localization of brain structures including the cortex, that can be used instead of indirect localization landmarks in stereotactic explorations, and further, that the wealth of anatomical information that can be drawn from angiography with their method may be helpful in diagnosis or for planning surgery.