| middle frontal sulcus | A relatively shallow sagittal fissure of the brain dividing the middle frontal convolution into an upper and lower part; this sulcus is found only in humans and anthropoid apes; at its anterior extremity it bifurcates, the two branches spreading out laterally and constituting the frontomarginal sulcus. Synonym: median frontal sulcus, sulcus frontalis medius. (05 Mar 2000) |
|---|---|
| middle temporal sulcus | The sulcus between the middle temporal gyrus and inferior temporal gyrus. Synonym: sulcus temporalis medius. (05 Mar 2000) |
| collateral sulcus | A long, deep sagittal fissure on the undersurface of the temporal lobe, marking the border between the fusiform gyrus laterally and the hippocampal and lingual gyri medially; the great depth of the collateral sulcus results in a bulging of the floor of the occipital and temporal horn of the lateral ventricle, the collateral eminence. Synonym: sulcus collateralis, sulcus occipitotemporalis, collateral fissure, fissura collateralis, occipitotemporal sulcus. (05 Mar 2000) |
| Monro's sulcus | A groove in the lateral wall of the third ventricle on either side leading from the interventricular foramen to the aditus ad aqueductum cerebri; the sulcus-demarcated boundary between dorsal thalamus and hypothalamus. Synonym: sulcus hypothalamicus, Monro's sulcus. (05 Mar 2000) |
| coronary sulcus | A groove on the outer surface of the heart marking the division between the atria and the ventricles. Synonym: sulcus coronarius, atrioventricular groove, atrioventricular sulcus, auriculoventricular groove, coronary sulcus. (05 Mar 2000) |
| costophrenic sulcus | The recess between the ribs and the lateral-most portion of the diaphragm, partially occupied by the most caudal part of the lung; seen on radiographs as the costophrenic angle. (05 Mar 2000) |
| postcentral sulcus | The sulcus that demarcates the postcentral gyrus from the superior and inferior parietal lobules. Synonym: sulcus postcentralis. (05 Mar 2000) |
| posterior branch of lateral cerebral sulcus | The long, posteriorly-directed continuation of the lateral cerebral sulcus which extends between the temporal lobe inferiorly and the parietal lobe superiorly, its termination surrounded by the supramarginal gyrus. Synonym: ramus posterior sulci lateralis cerebri. (05 Mar 2000) |
| habenular sulcus | A small groove located between the habenular trigone and the adjacent dorsal thalamus. (05 Mar 2000) |
| posterior intermediate sulcus | A longitudinal furrow between the posterior median and the posterolateral sulci of the spinal cord in the cervical region, marking the gracile fasciculus from the cuneate fasciculus. Synonym: sulcus intermedius posterior, posterior intermediate groove. (05 Mar 2000) |
| posterior median sulcus of medulla oblongata | The longitudinal groove marking the posterior midline of the medulla oblongata; continuous below with the posterior median sulcus of the spinal cord. Synonym: sulcus medianus posterior medullae oblongatae, posterior median fissure of the medulla oblongata. (05 Mar 2000) |
| posterior median sulcus of spinal cord | A shallow furrow in the median line of the posterior surface of the spinal cord. Synonym: sulcus medianus posterior medullae spinalis, posterior median fissure of spinal cord. (05 Mar 2000) |
| posterior parolfactory sulcus | A shallow groove on the medial surface of the hemisphere demarcating the subcallosal gyrus or precommissural septum from the parolfactory area. Synonym: sulcus parolfactorius posterior. (05 Mar 2000) |
| posterolateral sulcus | A longitudinal furrow on either side of the posterior median sulcus of the spinal cord marking the line of entrance of the posterior nerve roots. Synonym: sulcus lateralis posterior, posterolateral groove. (05 Mar 2000) |
| preauricular sulcus | A groove on the pelvic surface of the ilium just lateral to the auricular surface; it is more pronounced in the female. Synonym: paraglenoid groove, paraglenoid sulcus, preauricular sulcus, sulcus paraglenoidalis. (05 Mar 2000) |