dr. rima pathak. gross anatomy main sulci & gyri

Dr. Rima Pathak

Gross Anatomy

Main Sulci & Gyri

Cingulate

Central

Parieto Occipital

Postcentral gyrus

Cingulate

Thalamus

Caudate

Mid brain

4th ventricle

Pons

Inf Cerebellum

medulla

Spinal cord

Sella

Infundibular stalk

Precentral gyrus

Premotor area 6

Superior frontal gyrus

Pineal gland

Cingulate

Sylvian

Sup & middle Temporal

Median longitudinal fissure

Sup. Frontal

Inf. Frontal

Cingulate gyrus

Corpus callosum

Septum pellucidum

3rd Ventricle

Sup temporal gyrus

hippocampus

Internal Carotid A

Middle Frontal Gyrus

Inf Frontal Gyrus

Insular cortex

Inf Temporal Gyrus

Transverse Sinus

Formation of Basilar artery

Inf. Temporal gyrus

Internal carotid artery

Nasopharynx

Ethmoid air cells

lens

Eye ball

Optic nerve

Temporal horn of lat ventricle

Inf pons

Vermis

Parieto occipital sulcus

# Frontal LobeFalx cerebri

Caudate

Putamen

Choroid plexus

Splenium of corpus callosum

4th Ventricle

Thalamus & 3rd Ventricle

The Cerebral HemispheresCentral sulcus (of Rolando)Lateral sulcus (of Sylvius); Parietooccipital sulcus; Calcarine sulcus. Preoccipital notch

divide each

cerebral hemisphere

Frontal Lobe Anterior tip of the

brain (the frontal pole) to the central sulcus.

Inferiorly lateral sulcus/ Sylvian Fissure.

Medially extends anterior to an imaginary line from the top of the central sulcus to the corpus callosum.

AttentionBehavior, Abstract thinking,Problem solving, Creative thought, Emotion, Intellect, Initiative, Judgment, Coordinated movements, Muscle movements, smell, Physical reactions, and Personality.

Broca's Area opercular and triangular sections of the inferior frontal gyrus. Expressive language, speech. Damage .Sparse Relevant Speech/Low word output.

Parietal Lobe Anteriorly Central sulcus to an imaginary line

connecting the top of the parietooccipital sulcus and the preoccipital notch.

Inferiorly it is bounded by the lateral sulcus and the imaginary continuation of this sulcus to the posterior boundary of the parietal lobe.

Medially surface, it is bounded posteriorly by the corpus callosum and calcarine sulcus, anteriorly by the frontal lobe

Posterior by the parietooccipital sulcus.

four anatomical boundaries:the central sulcusthe parieto-occipital sulcusthe lateral sulcus (sylvian fissure)the medial longitudinal fissure the two hemispheres.

Sensory cortex is located in the front part of the parietal lobe. Receives information from the spinal cord about the sense of touch, pressure, pain, and the perception of the position of body parts and their movements.

Fissure of Rolando (central sulcus) to the parieto-occipital fissure behind. Below, it is limited anteriorly by the fissure of Sylvius, while its posterior portion merges into the temporosphenoidal lobe.

Temporal lobeSuperiorly: to the lateral sulcus and the line

forming the inferior boundary of the parietal lobePosteriorly: it extends to the line connecting the top

of the parietooccipital sulcus and the preoccipital notch.

Medial surface: its posterior boundary is an imaginary line from the preoccipital notch to the splenium of the corpus callosum.

Functions include comprehension, naming, verbal memory and other language functions. Sound processing is controlled by the temporal lobes- in the Broca’s area and Wernicke’s area.

The underside (ventral) part high-level visual processing of complex stimuli such as faces (fusiform gyrus) and scenes (parahippocampal gyrus) object perception and recognition.

The medial temporal lobes (near the Sagittal plane that divides left and right cerebral hemispheres) are thought to be involved in episodic/declarative memory.

The hippocampi seem to be particularly important for memory function - particularly transference from short to long term memory and control of spatial memory and behavior.

Auditory & Visual memories, language, hearing & speech, language, behavior

Wernicke's Area surrounds auditory cortex:understanding & formulating speech. Damage

Verbegeration/ Word salad.

Occipital lobeControls visionhomonomous vision loss

from similarly positioned "field cuts" in each eye.

visual hallucinations. parietal-temporal-occipital

lesions color agnosia, movement agnosia, and agraphia.

BrainstemCerebrum Spinal cord Motor and Sensory pathwaysCardiac and RespiratoryReflexesOriginating in the brainstem 10 of the 12 cranial nerves

Midbriancenter for ocular motionThe tectum (L. roof) of the midbrain consists of

paired lumps, the superior and inferior colliculi (L. small hills).

This is dorsal to the cerebral aqueduct

Ponscoordinating eye and facial movements, facial

sensation, hearing and balance.This consists of: A protruding basal portion, which is oval in the

sagittal section; And the overlying pontine tegmentum, which forms

part of the floor of the 4th ventricle.

Medullabreathing, blood pressure, heart rhythms and

swallowingreticular activating system is found in the midbrain,

pons, medulla and part of the thalamus. It controls levels of wakefulness, enables people to pay attention to their environments, and is involved in sleep patterns

The point of attachment of most cranial nerves

Optic PathwayOptic Chiasm is

located beneath the hypothalamus and is where the optic nerve crosses over to the opposite side of the brain

Cingulate GyrusThis is immediately superior to the corpus callosum. it continues as the parahippocampal gyrus of the

temporal lobe. These 2 gyri give the appearance of encircling the

diencephalon. They, together with the olfactory bulb and tract, and

certain other small cortical areas, are often referred to separately as the limbic lobe (L. limbus, border).

Pituitary Hypothalamus ComplexHypothalamus is a region of the brain in partnership with

the pituitary gland that controls the hormonal processes of the body as well as temperature, mood, hunger, and thirst.

This is inferior to the thalamus. It is separated from it by the hypothalamic sulcus in the wall of the 3rd

ventricle. It also forms the floor of the ventricle. Its inferior surface includes the infundibular stalk and the mammillary

bodies. The hypothalamus is the major visceral control centre of the brain. It is involved in the limbic system as well.

Basal Ganglia

CaudateThe round body bulging into the lateral ventricle and

forming its floor is the caudate nucleus

Thalamuslocated near the center

of the brain and controls input and output to and from the brain

sensation of pain and attention.

borders on the 3rd ventricle. major importance in both sensory and motor systems. The line of attachment of the roof of this ventricle is marked

by a horizontally oriented ridge, the stria medullaris thalami. medial surface of the 2 thalami fuse in many brains called

the interthalamic adhesion or massa intermedia. Posteriorly, the thalamus protrudes over the most rostral

part of the brainstem. Anteriorly, it abuts the interventricular foramen. No sensory information (except olfactory information)

reaches the cerebral cortex without prior processing in the thalami.

anatomical loops characteristic of motor systems, typically involve the thalami .

Putamen & Globus Pallidus

Insular cortexburied in the depths of the lateral

sulcus. It is concealed from view by

portions of the frontal, parietal, and temporal lobes.

The portion of a given lobe overlying the insula is called an operculum (L. lid).

There are frontal, parietal, and temporal opercula.

Pineal Regionon top of the midbrain behind the thalamusPineal Gland controls the response to light and

dark. Its principal hormone melatonin, a derivative of

amino acid tryptophan. stimulated by darkness and inhibited by light.

Follows circadian cycle with peak levels morning.

Hippocampus & Amygdala

Short term memory to long term memory.

The Papez Circuit.Amygdala controls

emotions, social inhibitions, aggression

Cerebellumlower back of the head and is connected to the brain

stem. It is the second largest structure of the brain and is

made up of two hemispheres. The cerebellum controls complex motor functions

such as walking, balance, posture, and general motor coordination

Ventricular SystemFour Ventricles of

the brain are connected cavities within the brain, where cerebrospinal fluid is produced

cavity shown in the septum pellucidum is the so-called fifth ve.ntricle

Lateral VentriclesTwo ventricles enclosed in the cerebral hemispheres

are called the lateral ventricles (first and second). They each communicate with the third ventricle through a separate opening called the Foramen of Munro

Third VentricleThe third ventricle is in the center of the brain, and

its walls are made up of the thalamus and hypothalamus.

The third ventricle connects with the fourth ventricle through a long tube called the Aqueduct of Sylvius.

Fourth VentricleCSF flowing through the

fourth ventricle flows around the brain and spinal cord by passing through another series of openings

Medial Mono MagendieBilateral Lushka

Lateral film

Anterior Film

THANK YOU

Hippocampal atrophy is a highly sensitive indicator of incipient AD. It's evaluation by MRI volumetry provides entirely additional data to support the diagnosis. In contrast, simpler measurements or T2 relaxometry provided only little diagnostic aid. The volume of the hippocampus correlated significantly with clinical severity assessed by MMSE, and with tests assessing delayed recall, which is considered to be affected early in dementia and may reflect hippocampal dysfunction.

2. The volume of the hippocampus is not significantly affected by normal aging.

AAMI can be differentiated from dementia by hippocampal volumetry

Three-Dimensional Fast Spoiled Gradient-Recalled (3D-SPGR) magnetic resonance imaging (MRI)

Standard 1.5 Tesla MRIModified T1 Post ContrastContiguous Sections2mm – 1mm thickness256 x 256 grid