Brain Anatomy.pptx

brain

1. ANATOMY OF BRAIN SULCUS AND GYRUS

2. Sulcus : A sulcus is depression or fissure in the surface of the brain. ( valleys ) Gyrus : A gyrus is a ridge on the cerebral cortex. It is generally surrounded by one or more sulci ( hills )

3. TYPICAL CONTINOUS FISSURE Interhemispheric fissure Sylvian fissure ( lateral sulcus ) Parieto -occipital fissure Collateral sulcus Central sulcus Calcarine Sulcus

4. INTERHEMISPHERIC FISSURE Deep sulcus up to corpus callosum Divides brain into two hemisphere

5. Deep, mostly horizontal Insula is buried within it Separates temporal lobe from parietal and frontal lobes SYLVIAN FISSURE

6. PARIETO - OCCIPITAL FISSURE Very deep Often y-shaped from sagittal view X-shaped in horizontal and coronal views

7. COLLATERAL SULCUS Divides lingual and parahippocampal gyri from fusiform gyrus.

8. CENTRAL SULCUS Usually freestanding (no intersections) Separates frontal and parietal lobe.

9. CALCARINE SULCUS

10. LOBES OF BRAIN Frontal lobe. Parietal lobe. Temporal lobe. Occipital lobe. Limbic lobe. Insular lobe.

11. FRONTAL LOBE: Anterior region of hemisphere; anterior to central sulcus, superior to sylvian fissure. PARIETAL LOBE: Posterior region of hemisphere; posterior to central sulcus, anterior to parietooccipital sulcus. OCCIPITAL LOBE: Posterior to parietooccipital sulcus. TEMPORAL LOBE : Inferior to sylvian fissure, anterior to angular gyrus

12. LATERAL SURFACE OF BRAIN

13. MEDIAL SURFACE OF BRAIN

14. BASAL SURFACE OF BRAIN

15. FRONTAL LOBE The frontal lobe constitutes the entire region in front of the central sulcus. Immediately in front of the central sulcus lies the precentral gyrus, which is the primary motor region of the cerebral cortex. In front of the precentral gyrus, the rest of the frontal lobe is divided into superior, middle and inferior frontal gyri .

16. FRONTAL LOBE SULCI: Superior frontal sulcus. Inferior frontal sulcus. Precentral sulcus. GYRI: Superior frontal gyrus. Middle frontal gyrus. Inferior frontal gyrus. Precentral gyrus

17. FRONTAL LOBE GYRUS Lateral Surface Precentral Gyrus --- primary motor area Superior Frontal Gyrus Middle Frontal Gyrus Inferior Frontal Gyrus Pars Opercularis Pars Triangularis Pars Orbitalis Medial Surface Medial Frontal Gyrus Paracentral Lobule Basal Surface Rectus Gyrus Orbital Gyrus ( superior, medial ,lateral ,inferior )

18. PARIETAL LOBE Behind the central sulcus, and above the lateral fissure, lies the parietal lobe. Its most anterior part is the postcentral gyrus, which is the site of the primary somatosensory cortex. Behind the postcentral gyrus, on the lateral surface of the hemisphere, the intraparietal sulcus divides the rest of the parietal lobe into superior and inferior parietal lobules.

19. PARIETAL LOBE SULCI: Post-central sulcus. Intraparietal sulcus. GYRI: Post-central gyrus. Superior parietal gyrus. Inferior parietal gyrus.

20. PARIETAL LOBE GYRUS Lateral Surface Postcentral Gyrus ---- primary somatic area Superior Parietal Lobule Inferior Parietal Lobule ---- Wernicke’s area Supramarginal Gyrus Angular Gyrus Medial Surface Paracentral Lobule Precuneus

21. The temporal lobe lies beneath the lateral fissure. On its lateral surface the temporal lobe is divided into three principal gyri that run roughly parallel to the lateral fissure: the superior, middle and inferior temporal gyri . The superior temporal gyrus includes the primary auditory cortex. TEMPORAL LOBE

22. Sulci : Superior temporal sulcus (parallel sulcus). Inferior temporal sulcus. Gyri : Superior temporal gyrus. Middle temporal gyrus. Inferior temporal gyrus. TEMPORAL LOBE

23. Lateral Surface Superior Temporal Gyrus Middle Temporal Gyrus Inferior Temporal Gyrus Basal Surface Occipitotemporal Gyrus Medial Occipitotemporal Gyrus Lateral Occipitotemporal Gyrus TEMPORAL LOBE GYRUS

24. OCCIPITAL LOBE The boundary between the parietal lobe and occipital lobe is not coincident with a single sulcus on the lateral surface of the hemisphere; however, it is clearly marked by the deep parieto-occipital sulcus on the medial surface. The occipital lobe does not bear any important landmarks on its lateral surface but on the medial surface, the prominent calcarine sulcus indicates the location of the primary visual cortex.

25. OCCIPITAL LOBE Sulci : Superior occipital sulcus (extension of intraparietal sulcus). Inferior occipital sulcus (extension of inferior temporal sulcus). Gyri : Superior occipital gyrus. Middle occipital gyrus. Inferior occipital gyrus

26. Lateral Surface Lateral Occipital Gyrus Superior Occipital Gyrus Inferior Occipital Gyrus Medial Surface Cuneus Lingual Gyrus Basal Surface Lateral occipito -temporal gyrus ( fusiform gyrus). Medial occipito -temporal gyrus (lingual gyrus). OCCIPITAL LOBE GYRUS

27. LIMBIC LOBE On the medial surface of the hemisphere, certain portions of the frontal, parietal and temporal lobes also constitute components of the limbic system. Curving around the corpus callosum, and running parallel to it, lies the cingulate gyrus , separated from the rest of the hemisphere by the cingulate sulcus. The cingulate gyrus passes posteriorly and inferiorly round the posterior portion of the corpus callosum to become continuous with the parahippocampal gyrus of the temporal lobe. Deep to the parahippocampal gyrus, within the temporal lobe lies the hippocampus. The cingulate gyrus, parahippocampal gyrus and hippocampus are referred to as the limbic lobe.

28. LIMBIC LOBE GYRUS Outer Ring Cingulate Gyrus Isthmus of Cingulate Gyrus Parahippocampal Gyrus Uncus , Uncinate Gyrus Inner Ring Hippocampal Formation Hippocampus, Ammon's Horn Dentate Gyrus Fasciolar Gyrus Supracallosal Gyrus Subcallosal Area ( Parolfactory Area)

29. Lies deep in floor of sylvian fissure, overlapped by frontal, temporal and parietal. The insular lobe is thought to be involved in sensory and motor visceral functions as well as taste perception. INSULAR LOBE

30. INSULAR LOBE Sulci : Central sulcus. Short insular sulcus. Precentral sulcus. Gyri : Anterior insular lobule. Posterior insular lobule.

31. Anterior insular lobule (short insular gyri ): Anterior short insular gyrus. Middle short insular gyrus. Posterior short insular gyrus. Posterior insular lobule (long insular gyri ): Anterior long insular gyrus. Posterior long insular gyrus. INSULAR LOBE

32. SULCUS AND GYRUS   Coronal Axial Sagittal

33. SIGNS TO IDENTIFY SULCUS IN MRI The midline sulcus sign : The longest sulcus running horizontally and entering the interhemispheric fissure is the central sulcus .   The M sign : The typical upper case M shape of the inferior frontal gyrus is formed by its parts ( orbitalis , triangularis , and opercularis ).

34. The bifid post cg sign : Toward the interhemispheric fissure, the postcentral gyrus is medially fissured, enclosing the pars marginalis of the cingulated sulcus with both legs and thereby forming the characteristic bifid post cg sign.   The thin post cg sign : On the surface, the precentral gyrus has a thicker anteroposterior diameter compared with the postcentral gyrus, which is thinner. SIGNS

35. SIGNS The handknob : Defined the " handknob " as 1 single -shaped dorsally convex bulge of the precentral gyrus.   The upper T sign : The intersection of the well-identifiable superior frontal sulcus with the precentral sulcus has the shape of an upper case T . The pre cg can be found immediately posterior to this T shape.

36. The L sign: The sfg terminates in the pre cg, which runs laterally from the posterior end of the sfg , therefore together forming an upper case L .   The lower T sign : The inferior frontal sulcus posteriorly terminates in the pre sc, also in the shape of an upper case T that is dorsally bordered by the pre cg. SIGNS

37. Inverted omega sign : The central sulcus more likely to have the shape of inverted omega.   The bracket sign : The bihemispheric symmetric pars marginalis of the cingulate sulcus forms an anteriorly opened bracket. SIGNS

38. SAGITTAL

39. Superior frontal gyrus Cingulate gyrus Cingulate sulcus Paracentral lobule Marginal ramus of Cingulate sulcus Superior parietal lobule Parietooccipital sulcus Cuneus Calcarine sulcus Lingual gyrus Fastigium , fourth ventricle Subcallosal gyrus Gyrus rectus

40. Cingulate sulcus Superior frontal gyrus Cingulate gyrus Precentral gyrus Central sulcus Marginal ramus of Cingulate sulcus Superior parietal lobule Precuneus Parietooccipital sulcus Cuneus Calcarine sulcus Lingual gyrus Caudothallamic groove Gyrus rectus Frontomarginal Gyrus

41. Superior frontal gyrus Corona radiata Precentral sulcus Central sulcus Marginal ramus of Cingulate sulcus Superior parietal lobule Precuneus Calcarine sulcus Parietooccipital sulcus Inferior occipital gyrus Lingual gyrus

42. Frontopolar gyrus Frontomarginal gyrus Medial orbital gyrus Posterior orbital gyrus Inferior temporal gyrus Temporal horn, Lateral ventricle Lingual gyrus Inferior occipital gyrus Middle occipital gyrus Superior occipital gyrus Parietooccipital sulcus Superior parietal lobule Central sulcus

43. Central sulcus Inferior temporal gyrus Superior temporal gyrus Middle Temporal gyrus

44. Central sulcus Superior parietal gyrus Superior occipital gyrus Middle occipital gyrus Inferior occipital gyrus Lingual gyrus Inferior temporal gyrus Middle Temporal gyrus Superior temporal gyrus Posterior orbital gyrus Anterior orbital gyrus Frontomarginal gyrus Inferior frontal gyrus

45. Inferior frontal gyrus , pars triangularis Inferior frontal gyrus, pars orbitalis Superior Temporal gyrus Superior Temporal sulcus Middle Temporal gyrus Inferior Temporal gyrus Inferior occipital gyrus Anterior occipital sulcus Middle occipital gyrus Angular gyrus Lateral fissure, posterior segment Postcentral sulcus Central sulcus Precentral sulcus Superior frontal sulcus

46. AXIAL

47. Fusiform gyrus Inferior Temporal gyrus Middle Temporal gyrus Superior Temporal gyrus

48. Hippocampal gyrus Parahippocampal gyrus Superior Temporal gyrus Middle Temporal gyrus Inferior Temporal gyrus

49. Amygdala Hippocampus Superior Temporal gyrus Middle Temporal gyrus Inferior Temporal gyrus Lingual gyrus Gyrus descendens Inferior occipital gyrus Temporo -occipital fissure

50. Hippocampus Amygdala Subcallosal gyrus Olfactory sulcus Gyrus rectus Medial orbital gyrus Posterior orbital gyrus Superior Temporal gyrus Middle Temporal gyrus Inferior Temporal gyrus Temporo -occipital fissure Middle occipital gyrus Gyrus descendens Lingual gyrus

51. Superior frontal gyrus Middle frontal gyrus Lateral fissure Inferior frontal gyrus, pars orbitalis Inferior frontal gyrus, pars opercularis Insula Cingulate gyrus Parieto -occipital fissure Calcarine sulcus Cuneus Superior occipital gyrus Intra-occipital sulcus Middle occipital gyrus Middle temporal gyrus Superior temporal sulcus Superior temporal gyrus Lateral fissure Inferior parietal gyrus

52. Middle frontal gyrus Superior frontal gyrus Inferior frontal gyrus Postcentral gyrus Inferior parietal gyrus Lateral fissure Superior temporal sulcus Parieto -occipital sulcus Superior occipital gyrus Intra-occipital sulcus Middle occipital gyrus Superior temporal gyrus Lateral fissure Central sulcus

53. Superior occipital gyrus Cuneus Intra-occipital sulcus Central sulcus Central sulcus Middle occipital gyrus Precentral gyrus Precentral sulcus

54. Superior frontal gyrus Superior frontal sulcus Centrum semiovale Central sulcus Postcentral sulcus Intraparietal sulcus Angular gyrus Superior parietal gyrus Precuneus Parietooccipital sulcus Supramarginal gyrus Postcentral sulcus Central sulcus Inferior frontal gyrus Middle frontal gyrus

55. Superior frontal gyrus Superior frontal sulcus Middle frontal gyrus Central sulcus Central sulcus Postcentral sulcus Intraparietal sulcus Pars marginalis Superior parietal gyrus Intraparietal sulcus Angular gyrus Supramarginal gyrus

56. CORONAL

57. Interhemispheric Fissure Inferior Frontal gyrus Olfactory bulb Superior frontal gyrus Middle frontal gyrus Inferior frontal gyrus Middle orbital gyrus Gyrus rectus

58. Superior frontal gyrus Superior frontal sulcus Middle frontal gyrus Inferior frontal gyrus Forceps minor Lateral orbital sulcus Lateral orbital gyrus medial orbital sulcus Olfactory sulcus Gyrus rectus Anterior Orbital gyrus

59. Circular insular sulcus Cingulate gyrus Superior Frontal gyrus Middle Frontal gyrus Inferior Frontal sulcus Inferior Frontal gyrus pars opercularis Sylvian Fissure Posterior Orbital gyrus medial orbital gyrus Gyrus rectus Olfactory sulcus Superior temporal gyrus Inferior temporal gyrus Middle temporal gyrus short insular gyrus

60. Superior frontal sulcus Superior frontal gyrus Cingulate gyrus Precentral sulcus Precentral gyrus Sylvian Fissure Middle frontal gyrus Superior temporal gyrus Superior temporal sulcus Middle temporal gyrus Amygdala Anterior commissure Inferior temporal gyrus

61. Hippocampus Central sulcus Middle Frontal gyrus Superior Frontal gyrus Superior temporal gyrus Middle temporal gyrus Inferior temporal gyrus Fusiform gyrus CA1, cornuammonis Parahippocampal gyrus

62. Supramarginal gyrus Intraparietal sulcus Cingulate gyrus Paracentral lobule Central Sulcus Postcentral gyrus Intraparietal sulcus Superior temporal gyrus Middle temporal gyrus Inferior temporal gyrus Fusiform gyrus Parahippocampal gyrus Collateral sulcus

63. Paracentral lobule Central Sulcus Superior temporal gyrus Middle temporal gyrus Inferior temporal gyrus Fusiform gyrus

64. Paracentral lobule Central Sulcus Postcentral gyrus Supramarginal gyrus Intraparietal sulcus Middle temporal gyrus Inferior temporal gyrus Cingulate gyrus Calcarine sulcus Lingual gyrus Fusiform gyrus

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