Sagittal Plane

The sagittal plane is one of the three principal anatomical planes used to examine the brain and nervous system. It is a vertical plane extending in an anterior-posterior direction and divides the brain or body into right and left portions.

Sagittal neuroimaging is especially important because a section through the midline reveals structures that are difficult to appreciate completely on axial or coronal images. These include the corpus callosum, third ventricle, cerebral aqueduct, fourth ventricle, brainstem, cerebellar vermis, pituitary region, and upper cervical spinal cord.

Sections positioned lateral to the midline demonstrate the cerebral hemispheres, lateral ventricles, deep white matter, basal ganglia, medial temporal structures, and other anatomy. Reviewing sequential sagittal sections therefore provides a side-to-side representation of the nervous system.

Definition of the Sagittal Plane

A sagittal plane is a vertical plane running from anterior to posterior. It separates structures on the right side of the body from those on the left.

A sagittal section passing exactly through the midline is called a midsagittal or median section. Sagittal sections located away from the midline are described as parasagittal sections.

Major Neuroimaging Planes

Plane	Division	General View
Axial	Superior and inferior	Horizontal cross-section
Coronal	Anterior and posterior	Front-facing cross-section
Sagittal	Right and left	Side-facing section

Midsagittal Plane

The midsagittal plane passes through the midline of the head and brain. It is particularly useful because numerous important neuroanatomical structures either lie directly in the midline or cross it.

A midsagittal MRI provides one of the clearest overall views of the relationship between the cerebrum, diencephalon, brainstem, cerebellum, ventricular system, and spinal cord.

Parasagittal Plane

A parasagittal plane is any sagittal section positioned lateral to the exact midline. Moving progressively laterally reveals different parts of the cerebral hemispheres and deep structures.

Parasagittal images are important for tracing the lateral ventricles, cortical gyri, white matter pathways, medial cerebral surfaces, and lesions extending away from the midline.

Sagittal Image Orientation

On a conventional sagittal image, the superior direction is displayed at the top and the inferior direction at the bottom. Anterior and posterior depend on how the image is displayed, but orientation markers should always be checked.

In many standard sagittal brain images, anterior structures such as the frontal lobe and face are displayed toward the left side of the image, while posterior structures such as the occipital lobe and cerebellum are toward the right. Display conventions can vary, so anatomical markers remain essential.

Sagittal Orientation Guide

Relationship	Meaning
Superior	Toward the cerebral convexity
Inferior	Toward the skull base
Anterior	Toward the frontal lobes and face
Posterior	Toward the occipital lobe and posterior fossa
Medial	Toward the midsagittal plane
Lateral	Away from the midsagittal plane

Structures Visible on Midsagittal Imaging

A high-quality midsagittal MRI may demonstrate:

• Corpus callosum
• Cingulate gyrus
• Septal region
• Fornix
• Third ventricle
• Hypothalamic region
• Pituitary gland and stalk
• Optic chiasm
• Pineal region
• Cerebral aqueduct
• Midbrain
• Pons
• Medulla oblongata
• Fourth ventricle
• Cerebellar vermis
• Upper cervical spinal cord

Corpus Callosum

The corpus callosum is one of the most conspicuous structures on midsagittal MRI. It is the largest commissural fiber bundle connecting corresponding and related regions of the two cerebral hemispheres.

Its curved profile provides an important landmark for identifying surrounding midline anatomy.

Parts of the Corpus Callosum

Part	Location
Rostrum	Thin inferior anterior portion
Genu	Curved anterior portion
Body	Long central portion
Splenium	Thickened posterior portion

Rostrum of the Corpus Callosum

The rostrum is the thin inferior extension of the anterior corpus callosum. It curves posteriorly from the genu and contributes fibers connecting inferior frontal regions.

Its small size means that it is generally most easily identified on a true midsagittal high-resolution image.

Genu of the Corpus Callosum

The genu forms the rounded anterior bend of the corpus callosum. It lies anterior to the frontal horns of the lateral ventricular system.

Fibers from the genu curve anteriorly into the frontal lobes.

Body of the Corpus Callosum

The body extends posteriorly from the genu and forms a major part of the roof of the lateral ventricular region.

Its relationship with the cingulate gyrus superiorly and ventricular structures inferiorly is particularly clear on sagittal MRI.

Splenium of the Corpus Callosum

The splenium is the enlarged posterior portion of the corpus callosum. It contains commissural fibers connecting posterior cerebral regions.

On midsagittal imaging, its rounded posterior contour provides an important landmark above the posterior diencephalic and midbrain regions.

Cingulate Gyrus

The cingulate gyrus curves around the superior surface of the corpus callosum on the medial aspect of the cerebral hemisphere.

It is part of the limbic cortex and can be followed from anterior regions around the callosal body toward posterior medial cerebral structures.

Cingulate Sulcus

The cingulate sulcus lies superior to the cingulate gyrus and helps separate it from adjacent medial frontal and parietal cortex.

Its course is an important landmark when studying the medial surface of the cerebral hemisphere.

Fornix

The fornix is a major white matter pathway associated with the hippocampal formation. Portions of the fornix can be seen inferior to the corpus callosum on midsagittal and near-midline images.

It arches through the cerebral interior and connects hippocampal structures with diencephalic and basal forebrain regions.

Septum Pellucidum

The septum pellucidum is a thin membrane positioned between portions of the corpus callosum and fornix. It separates the frontal horns and portions of the bodies of the lateral ventricles.

Its relationship to the corpus callosum and fornix is particularly easy to understand when sagittal and coronal images are reviewed together.

Ventricular System in the Sagittal Plane

The sagittal plane provides an excellent view of the continuity of the central CSF pathways. A midsagittal image can demonstrate the third ventricle, cerebral aqueduct, and fourth ventricle in a nearly continuous sequence.

Near-midline parasagittal images also demonstrate portions of the lateral ventricles.

Third Ventricle

The third ventricle is a narrow midline cavity within the diencephalon. On sagittal imaging it lies inferior to portions of the fornix and corpus callosum and superior to hypothalamic structures.

Posteriorly, it communicates with the cerebral aqueduct.

Cerebral Aqueduct

The cerebral aqueduct is a narrow CSF channel passing through the midbrain and connecting the third ventricle to the fourth ventricle.

Its full anterior-posterior course is particularly well demonstrated on midsagittal MRI.

Fourth Ventricle

The fourth ventricle is located between the brainstem anteriorly and cerebellum posteriorly. On midsagittal images it appears as a CSF-containing cavity posterior to the pons and upper medulla.

Its superior portion is continuous with the cerebral aqueduct, while its inferior region approaches the central canal and outlets to the subarachnoid space.

CSF Pathway on Sagittal Imaging

Sagittal imaging allows the central CSF pathway to be conceptualized as a continuous system:

1. Lateral ventricles
2. Interventricular foramina
3. Third ventricle
4. Cerebral aqueduct
5. Fourth ventricle
6. Subarachnoid space and central canal pathways

Diencephalon

The diencephalon lies between the cerebral hemispheres and brainstem and includes the thalamic, hypothalamic, epithalamic, and related regions.

Midsagittal and near-midline images provide important views of the third ventricular region and the structures forming its boundaries.

Thalamic Region

The paired thalami are predominantly located lateral to the true midsagittal plane, so their full extent is better appreciated on parasagittal, axial, and coronal images.

Near-midline sagittal images demonstrate their relationship to the third ventricle and midbrain.

Hypothalamus

The hypothalamus lies inferior to the thalamic region and contributes to the walls and floor of the third ventricle.

Sagittal imaging demonstrates its relationship to the optic chiasm, pituitary stalk, mammillary region, and midbrain.

Pituitary Gland

The pituitary gland lies within the sella turcica at the skull base. Sagittal MRI provides an excellent view of the gland's anterior-posterior and superior-inferior dimensions.

The pituitary stalk extends superiorly toward the hypothalamus.

Pituitary Stalk

The infundibulum or pituitary stalk connects the pituitary gland with the hypothalamic region. It can often be followed on sagittal imaging from the superior surface of the gland toward the floor of the third ventricular region.

Coronal images provide complementary information about its right-left position.

Optic Chiasm

The optic chiasm lies superior to the pituitary gland and anterior to the pituitary stalk and hypothalamic region.

Sagittal imaging is particularly useful for demonstrating the vertical relationship between the pituitary gland and optic chiasm.

Sellar and Suprasellar Region

The sagittal plane is important for evaluating the sellar and suprasellar regions. It demonstrates the pituitary gland, sella turcica, pituitary stalk, optic chiasm, hypothalamic region, and adjacent cisterns in profile.

Coronal images are usually reviewed alongside sagittal images to assess lateral relationships.

Pineal Region

The pineal gland lies in the posterior diencephalic region near the roof of the third ventricle and superior to the tectal plate of the midbrain.

Its midline position makes sagittal imaging particularly useful for understanding its anatomical relationships.

Brainstem on Sagittal Imaging

The sagittal plane provides a continuous side view of the midbrain, pons, and medulla oblongata. This makes it one of the most useful planes for understanding the overall organization of the brainstem.

The brainstem can be followed inferiorly into the cervical spinal cord and superiorly into the diencephalic region.

Midbrain

The midbrain is the superior portion of the brainstem. On midsagittal imaging it lies inferior to the diencephalon, anterior to the cerebral aqueduct and tectal region, and superior to the pons.

The cerebral aqueduct provides an important landmark for identifying the midbrain.

Tectum

The tectum forms the dorsal portion of the midbrain posterior to the cerebral aqueduct. It includes the superior and inferior colliculi.

The paired colliculi are most completely evaluated on images slightly lateral to the exact midline, but their region is readily recognized sagittally.

Superior Colliculus

The superior colliculus forms part of the dorsal midbrain and participates in visual orienting and related reflex pathways.

It lies superior to the inferior colliculus on the posterior surface of the midbrain.

Inferior Colliculus

The inferior colliculus lies inferior to the superior colliculus and is an important relay structure within auditory pathways.

Its position on the dorsal midbrain can be appreciated on sagittal and parasagittal MRI.

Pons

The pons forms the prominent middle portion of the brainstem. On sagittal imaging its convex ventral surface is easily recognized anterior to the fourth ventricle.

Posteriorly, the pons contributes to the floor of the fourth ventricle.

Medulla Oblongata

The medulla oblongata lies inferior to the pons and becomes continuous with the spinal cord at the lower brainstem.

Sagittal imaging clearly demonstrates this transition and the relationship of the medulla to the fourth ventricle and cerebellum.

Brainstem and Spinal Cord Continuity

One of the major advantages of the sagittal plane is its ability to demonstrate the continuous longitudinal relationship between the brainstem and spinal cord.

The medulla passes inferiorly through the foramen magnum and becomes continuous with the cervical spinal cord.

Cerebellum

The cerebellum lies posterior to the brainstem and inferior to the occipital lobes. Midsagittal imaging provides an excellent view of the cerebellar vermis and the relationship of the cerebellum to the fourth ventricle.

More lateral sagittal images progressively demonstrate the cerebellar hemispheres.

Cerebellar Vermis

The vermis is the midline portion of the cerebellum connecting the two cerebellar hemispheres. It is particularly well demonstrated on midsagittal MRI.

The characteristic branching pattern of cerebellar white matter is visible within the vermian region on suitable sequences.

Arbor Vitae

The arbor vitae refers to the branching arrangement of cerebellar white matter seen in section. Its tree-like configuration is particularly recognizable on sagittal images.

The surrounding cerebellar cortex forms thin folds called folia.

Cerebellar Tonsils

The cerebellar tonsils are paired inferior portions of the cerebellar hemispheres located near the foramen magnum.

Sagittal MRI is commonly used to assess their position relative to the foramen magnum and craniocervical junction.

Foramen Magnum

The foramen magnum is the large opening at the base of the skull through which the medulla becomes continuous with the spinal cord.

Sagittal imaging clearly demonstrates the relationship between the foramen magnum, lower brainstem, upper cervical cord, cerebellar tonsils, and surrounding CSF spaces.

Craniocervical Junction

The craniocervical junction includes the anatomical transition between the skull base and upper cervical spine. Important neural structures include the lower medulla, upper cervical spinal cord, and adjacent CSF spaces.

Sagittal MRI provides a particularly useful overview of this region.

Medial Surface of the Cerebral Hemisphere

The sagittal plane exposes the medial surface of the cerebral hemisphere, allowing several cortical regions and sulci to be identified.

Important structures include the cingulate gyrus, paracentral lobule, precuneus, cuneus, and medial occipital cortex.

Paracentral Lobule

The paracentral lobule lies on the medial surface of the cerebral hemisphere around the continuation of the central sulcus.

It contains medial portions of the primary motor and somatosensory cortices associated predominantly with the contralateral lower limb.

Precuneus

The precuneus is located on the medial surface of the parietal lobe. It lies posterior to the paracentral lobule and anterior to the parieto-occipital sulcus.

Its boundaries are particularly useful when learning medial cerebral surface anatomy.

Parieto-Occipital Sulcus

The parieto-occipital sulcus is a prominent sulcus on the medial cerebral surface separating portions of the parietal and occipital lobes.

It is an important landmark on sagittal anatomical and MRI sections.

Calcarine Sulcus

The calcarine sulcus lies on the medial surface of the occipital lobe. Primary visual cortex is located along its banks.

The sagittal plane provides an excellent view of the course of this sulcus and its relationship to surrounding occipital cortex.

Cuneus

The cuneus is a wedge-shaped region of medial occipital cortex located between the parieto-occipital sulcus and calcarine sulcus.

It is readily identified when these two major sulci are visible on sagittal imaging.

Lingual Gyrus

The lingual gyrus lies inferior to the calcarine sulcus on the medial occipital and posterior temporal surface.

It forms part of the visual association cortex and can be identified on appropriate medial sagittal sections.

Lateral Ventricles on Parasagittal Images

The lateral ventricles lie lateral to the exact midsagittal plane and are therefore better demonstrated on parasagittal sections.

Moving laterally from the midline reveals different portions of the ventricular system, including the frontal horn, body, atrium, occipital horn, and temporal horn.

Basal Ganglia on Sagittal Imaging

The basal ganglia are predominantly lateral structures and are not fully represented on a true midsagittal image. Parasagittal sections can demonstrate portions of the caudate nucleus, lentiform nucleus, and adjacent internal capsule.

Axial and coronal planes are generally more intuitive for studying the relationships among these deep nuclei.

Internal Capsule on Sagittal Imaging

Parasagittal MRI can demonstrate the superior-inferior course of fibers associated with the internal capsule and corona radiata.

However, the distinction between the anterior limb, genu, and posterior limb is usually more clearly appreciated on axial sections.

Temporal Lobe on Sagittal Imaging

Lateral sagittal sections demonstrate the temporal lobe in profile. The superior, middle, and inferior temporal gyri can be appreciated on sufficiently lateral images.

More medial sections demonstrate structures related to the parahippocampal region and hippocampal formation.

Hippocampus on Sagittal Imaging

The hippocampus extends along the medial temporal lobe in an anterior-posterior direction. Parasagittal MRI can demonstrate portions of its longitudinal course.

Coronal images oriented perpendicular to the hippocampal long axis are generally preferred for detailed assessment of its cross-sectional morphology.

Gray Matter and White Matter

Sagittal CT and MRI demonstrate the relationship between cortical gray matter, cerebral white matter, deep structures, and ventricular CSF.

The relative appearance of gray and white matter varies according to imaging modality and MRI sequence.

Sagittal T1-Weighted MRI

On conventional T1-weighted MRI, cerebral white matter generally appears brighter than gray matter, while cerebrospinal fluid is dark.

T1-weighted sagittal images provide excellent anatomical definition and are frequently used for structural assessment of the corpus callosum, brainstem, cerebellum, pituitary region, and ventricular system.

Sagittal T2-Weighted MRI

On conventional T2-weighted MRI, cerebrospinal fluid appears bright and white matter is relatively darker than on T1-weighted imaging.

T2-weighted sagittal images provide useful information about the spinal cord, brainstem, CSF spaces, and many pathological processes.

Sagittal FLAIR MRI

FLAIR suppresses the signal of normal CSF while preserving sensitivity to many abnormalities that are hyperintense on T2-weighted imaging.

Sagittal FLAIR can be useful for assessing lesions involving the corpus callosum, periventricular white matter, brainstem, and cerebral hemispheres.

CT in the Sagittal Plane

Routine head CT data can often be reconstructed into sagittal images from thin-section volumetric acquisitions. These reconstructions provide additional information about the vertical and anterior-posterior extent of abnormalities.

Sagittal CT is particularly useful for evaluating skull anatomy, fractures, ventricular relationships, mass effect, and the craniocervical region.

MRI in the Sagittal Plane

MRI provides high soft-tissue contrast and is especially suited to sagittal neuroanatomy. A sagittal sequence is commonly included in brain MRI protocols because it provides rapid assessment of midline structures and overall brain morphology.

It also serves as an important reference for planning axial and coronal sequences.

Sagittal Plane in Hydrocephalus

The sagittal plane demonstrates the relationship between the third ventricle, cerebral aqueduct, fourth ventricle, and surrounding brain structures.

This makes it useful for identifying the anatomical level of obstruction in certain forms of hydrocephalus when combined with axial and coronal imaging.

Aqueductal Obstruction

Narrowing or obstruction of the cerebral aqueduct can interfere with CSF flow between the third and fourth ventricles.

Sagittal imaging is particularly valuable because the aqueduct can be viewed along much of its course between these ventricular compartments.

Sagittal Plane in Posterior Fossa Evaluation

The posterior fossa contains the brainstem, cerebellum, fourth ventricle, and associated CSF spaces. Sagittal imaging clearly demonstrates their anterior-posterior and superior-inferior relationships.

It is particularly useful for assessing the cerebellar vermis, fourth ventricle, brainstem contour, and craniocervical junction.

Sagittal Plane in Pituitary Imaging

Sagittal MRI is commonly used for detailed evaluation of the pituitary gland and suprasellar region. It demonstrates the height and contour of the gland and its relationship to the sphenoid sinus, pituitary stalk, optic chiasm, and hypothalamic structures.

Coronal imaging complements this by showing lateral relationships with the cavernous sinuses and internal carotid arteries.

Sagittal Plane in Corpus Callosum Evaluation

The corpus callosum is best appreciated as a complete structure on midsagittal imaging. Its rostrum, genu, body, and splenium can be examined for continuity, thickness, morphology, and signal characteristics.

Because the corpus callosum lies near the midline, abnormalities affecting it may be particularly conspicuous on sagittal MRI.

Sagittal Plane in Brainstem Lesions

Sagittal imaging helps determine the superior-inferior and anterior-posterior extent of lesions involving the midbrain, pons, and medulla.

Axial images remain important for determining whether a brainstem lesion is medial or lateral, so the two planes are complementary.

Sagittal Plane in Cerebellar Lesions

Midsagittal imaging provides detailed assessment of the cerebellar vermis, while parasagittal images progressively demonstrate the cerebellar hemispheres.

The relationship of a lesion to the fourth ventricle, brainstem, tentorial region, and foramen magnum can be evaluated using sagittal images.

Sagittal Plane in Craniocervical Junction Imaging

Sagittal MRI is particularly useful for studying the transition between the posterior fossa and cervical spinal canal. The cerebellar tonsils, foramen magnum, medulla, cervical spinal cord, and surrounding CSF spaces can be examined together.

This provides a clear overview of anatomical relationships that may be difficult to appreciate from a single axial section.

Sagittal Plane in Spinal Imaging

The sagittal plane is also fundamental to imaging of the spinal cord and vertebral canal. It allows the spinal cord to be followed longitudinally across multiple vertebral levels.

Axial spinal images are then used to provide detailed cross-sectional localization at specific levels.

Spinal Cord on Sagittal MRI

Sagittal MRI demonstrates the cervical, thoracic, and lumbar spinal canal in longitudinal profile. The spinal cord, surrounding CSF, vertebral bodies, intervertebral discs, and posterior elements can be evaluated over multiple levels.

This orientation is particularly useful for determining the superior-inferior extent of spinal cord lesions.

Sagittal Plane in Mass Lesions

Intracranial masses can be evaluated according to their anterior-posterior and superior-inferior extent on sagittal images. Their relationships to the corpus callosum, ventricular system, brainstem, cerebellum, and skull base may be particularly clear.

Multiplanar imaging remains necessary for complete assessment of right-left extension.

Sagittal Plane in Midline Lesions

Lesions arising near the cerebral midline are particularly suited to sagittal evaluation. These may involve the corpus callosum, third ventricular region, pineal region, pituitary region, brainstem, cerebellar vermis, or ventricular pathways.

The midsagittal plane can demonstrate their relationship to several adjacent structures simultaneously.

Sagittal Plane in Brain Herniation

Sagittal imaging can demonstrate abnormal displacement of cerebral, diencephalic, brainstem, and cerebellar structures caused by intracranial mass effect.

The position of the brainstem, cerebellar tonsils, ventricular system, and basal structures can be evaluated together with axial and coronal findings.

Sagittal Plane in Stroke Imaging

Although acute stroke is commonly recognized and localized on axial diffusion-weighted and CT images, sagittal views can provide complementary information about the superior-inferior and anterior-posterior extent of infarction.

Sagittal reconstructions can also help demonstrate lesions involving the corpus callosum, brainstem, cerebellum, and medial cerebral surfaces.

Sagittal Plane in White Matter Evaluation

Sagittal MRI demonstrates the cerebral white matter in profile and provides particularly useful views of the corpus callosum and periventricular regions.

White matter abnormalities should be correlated with axial and coronal images to determine their full distribution.

Multiplanar Reconstruction

Modern volumetric CT and MRI acquisitions can often be reconstructed into sagittal images without requiring a separate acquisition in that plane.

Thin-section isotropic datasets allow high-quality sagittal, axial, coronal, and oblique reconstructions from the same source data.

Sagittal and Axial Relationship

The sagittal plane emphasizes anterior-posterior and superior-inferior relationships, while the axial plane emphasizes anterior-posterior and right-left relationships.

Combining these planes is especially useful for localizing brainstem, ventricular, cerebral, and posterior fossa structures.

Sagittal and Coronal Relationship

The coronal plane emphasizes superior-inferior and right-left relationships, while the sagittal plane shows the same anatomy from the side.

Structures such as the corpus callosum, pituitary region, hippocampus, ventricles, and brainstem are best understood by correlating both orientations.

Advantages of the Sagittal Plane

• Provides an excellent overview of midline brain anatomy
• Displays the complete profile of the corpus callosum
• Demonstrates the relationship of the third ventricle, aqueduct, and fourth ventricle
• Shows the midbrain, pons, and medulla in continuity
• Provides detailed visualization of the cerebellar vermis
• Clearly demonstrates the sellar and suprasellar regions
• Shows the craniocervical junction and brainstem-spinal cord transition
• Provides longitudinal views of the spinal cord

Limitations of the Sagittal Plane

A true midsagittal image provides limited information about structures located far from the midline. Deep nuclei such as the putamen and many lateral cortical structures require parasagittal sections or other imaging planes for complete assessment.

Right-left relationships are also less intuitive on a single sagittal image than on axial or coronal sections.

Common Orientation Errors

Error	Correct Approach
Assuming every sagittal image is midsagittal	Determine whether true midline structures are present
Confusing anterior and posterior	Use the face, frontal lobe, occipital lobe, brainstem, and cerebellum as landmarks
Ignoring laterality	Check whether the image is right or left parasagittal
Identifying structures by shape alone	Use neighboring anatomical relationships
Reviewing only the midsagittal slice	Follow structures through adjacent parasagittal sections
Ignoring other planes	Correlate sagittal anatomy with axial and coronal images

Recognizing a True Midsagittal Image

A true midsagittal image contains several characteristic midline structures. Their simultaneous presence helps confirm that the section is near the median plane.

• Corpus callosum in profile
• Third ventricle region
• Cerebral aqueduct
• Fourth ventricle
• Brainstem in longitudinal profile
• Cerebellar vermis
• Pituitary stalk region
• Upper cervical spinal cord

Practical Sagittal Reading Sequence

1. Determine whether the image is midsagittal or parasagittal.
2. Confirm the anterior, posterior, superior, and inferior directions.
3. Identify the corpus callosum.
4. Locate the ventricular system.
5. Identify the diencephalic and pituitary regions.
6. Follow the midbrain, pons, and medulla.
7. Examine the cerebellum and fourth ventricle.
8. Assess the foramen magnum and craniocervical junction.
9. Identify the medial cerebral cortex and major sulci.
10. Move laterally through adjacent sections to evaluate hemispheric structures.
11. Correlate findings with axial and coronal images.

Key Sagittal Landmarks

Landmark	What It Helps Identify
Corpus callosum	Midline cerebral anatomy and ventricular relationships
Third ventricle	Diencephalic region
Cerebral aqueduct	Midbrain and CSF pathway
Fourth ventricle	Brainstem-cerebellar relationship
Pons	Central brainstem level
Cerebellar vermis	Midline cerebellum
Pituitary gland	Sellar and suprasellar anatomy
Foramen magnum	Craniocervical junction
Calcarine sulcus	Medial visual cortex

Clinical Importance

The sagittal plane is fundamental to neuroimaging because it provides a continuous side view of the nervous system and is especially effective for displaying midline anatomy. The corpus callosum, ventricular pathways, brainstem, cerebellar vermis, pituitary region, and craniocervical junction can all be related to one another within a single orientation.

Sagittal imaging is therefore particularly useful in the evaluation of abnormalities involving the corpus callosum, pituitary and suprasellar region, posterior fossa, brainstem, ventricular system, craniocervical junction, spinal cord, and other midline structures.

Functional Importance

The sagittal plane provides a powerful framework for understanding the longitudinal organization of the nervous system. The cerebral hemispheres lie superior to the diencephalon and brainstem, the brainstem continues inferiorly into the spinal cord, and the cerebellum occupies the posterior fossa behind the brainstem.

At the midline, the corpus callosum provides a major landmark for cerebral anatomy. Inferior to it lie the fornix and ventricular structures. The third ventricle communicates posteriorly with the cerebral aqueduct, which passes through the midbrain to the fourth ventricle between the brainstem and cerebellum.

The plane also exposes the medial surface of the cerebral hemisphere, where structures such as the cingulate gyrus, paracentral lobule, precuneus, parieto-occipital sulcus, cuneus, and calcarine sulcus can be studied in their anatomical relationships.

Mastery of the sagittal plane provides a foundation for understanding brain MRI, midsagittal neuroanatomy, corpus callosum anatomy, ventricular anatomy, brainstem anatomy, cerebellar anatomy, pituitary imaging, craniocervical anatomy, spinal MRI, and multiplanar neuroimaging.