Localization Of Cerebral Sulci And Gyri On The Cross Section

To provide the section anatomic data for imaging study of brain functions and MRI localization of cerebral local lesions, 30 cadaver heads were used. The heads were scanned by 4.0 mm thickness using Philips 1.5 Tesla MR scanner and taking out the brain from the scanned head, the important cerebral gyri were painted by different colors. The preparation of the brain slice in correspondence with MR scan took the perpendicular to midpoint line of AC-PC as base line. The brain slice was correspondent to the MR imaging by 4.0 mm thickness. The localization of cerebral sulci and gyri on the cross sections were studied by the comparison of the MR images with serial cross sections of the brains.1. (1)On the sections in front of corpus callousm, the appearing rate of 丁-shaped sulci was 73% on the left side and 60% on the right side. It could be useful to identify the central sulcus. (2)On the sections before the -shaped sulci and L-shaped lateral sulci appeared, three parallel sulci were constructed the precentral sulcus, the central sulcus and the postcentral sulcus, and the precentral gyrus was thicker than postcentral gyrus, or the characters of the medullary branch of postcentral gyrus were obvious. It could be useful to identify the central sulcus. (3)On the section appearing insular lobe with L-shaped lateral sulcus, the postcentral gyrus or central sulcus was corresponded the short gyri of insula. The appearing rate was 85% on the left side and 93% on the right side. 2. On the section appearing body of caudate nucleus for the first time, the appearing rate of the posterior ascending rami of lateral sulcus was 17% on the left side and 40% on the right side. On the section appearing head of caudate nucleus and internal capsule for thefirst time, the appearing rate of the posterior ascending rami of lateral sulcus was 100% and the rate of the dorsal thalamus was 10%. On the section appearing posterior ascending ramus of lateral sulcus for the first time, the appearing rate of the head of caudate nucleus was 87% on the left side and 60% on the right side, and the appearing rate of the dorsal thalamus was 13% on the left side and 3% on the right side. The body of caudate nucleus only appeared on the 1 or 2 sections. It means that the posterior ascending ramus of lateral sulcus appearing for the first time could be identified on the 2-3 sections from with body of caudate nucleus to with head of caudate nucleus and internal capsule without dorsal thalamus.3. (1)On the section appearing parietooccipital sulcus for the first time, the appearing rate of the hook-shaped occipital lobe was 77% on the left side and 80% on the right side, and the rate of trunk of corpus callousm was 70% on the left side and 63% on the right side. Basal nuclei didn't appear in the most of sections. On the section appearing corpus callousm for the first time, the appearing rate of the parietooccipital sulcus was 90%. On the section appearing the head of caudate nucleus for the first time, the appearing rate of parietoociipital sulcus was 100%. It means the parietooccipital sulcus was appeared 1-2 slices before the head and body of caudate nucleus. (2)On the section appearing hippocampuss for the first time and its upper sections, the disappearing rate of the parietooccipital sulcus was 90% on the left side and 80% on the right side. It means the parietooccipital sulcus disappered as soon as the hippocampuss appeared. (3)The appearing rate of the Y-shaped or V-shaped parietooccipital sulcus was 66% on the left side and 78% on the right side, the others was strait shaped.