SECTIONAL ANATOMY AND PATHOLOGY · LESSON 47

Brain, head, and neck anatomy.

Build a reliable map from the top of the brain through the skull base and neck. Learn the major landmarks first, then use symmetry, compartments, and neighboring structures to stay oriented.

About 19 minutesS.I.D.E.S. method5 anatomy checks
01BRAINLobes and deep structures
+
02SKULL BASEOrbits, sella, posterior fossa
+
03NECKAirway, glands, vessels

SCROLL THE STACK · FOLLOW THE LANDMARKS

01EXPLAIN

LEARN RELATIONSHIPS, NOT ISOLATED NAMES

Anatomy becomes easier when every structure has an address.

Start with the plane and image labels. Find the midline, the outer contour, and a dependable landmark. Then ask what sits anterior, posterior, medial, lateral, superior, and inferior to it. This turns a crowded image into an organized map.

MRI appearance changes with T1, T2, FLAIR, diffusion, susceptibility, fat suppression, and contrast. Cerebrospinal fluid can be bright on one sequence and dark on another. Gray and white matter contrast can reverse. Identify a structure by its location, shape, and connections, not by brightness alone.

IN PLAIN LANGUAGELocation tells you what a structure could be. Shape and neighboring anatomy help confirm it. Signal depends on the sequence.
ANATOMY STUDY IS NOT IMAGE INTERPRETATION

Recognizing landmarks supports image quality and planning.

Diagnosing pathology belongs to the qualified interpreting clinician. The technologist uses anatomy to plan coverage, position slices, evaluate technical quality, and recognize when additional clinical review may be needed under policy.

02BRAIN

TAKE AN AXIAL SLICE WALK

Move from the vertex toward the skull base.

1High convexity

Near the top of the head, identify the two cerebral hemispheres, cortical gray matter, underlying white matter, interhemispheric fissure, falx, and superior sagittal sinus region.

2Centrum semiovale and ventricles

As you move lower, the deep cerebral white matter becomes more prominent. The bodies of the lateral ventricles appear near the midline, with the corpus callosum arching around the ventricular system.

3Deep gray structures

At the basal ganglia level, find the caudate, putamen, and globus pallidus. The internal capsule runs between the deep gray structures. The paired thalami sit near the third ventricle.

4Temporal lobes and midbrain

Continue through the temporal lobes, basal cisterns, midbrain, cerebral peduncles, and aqueduct region. The hippocampi sit within the medial temporal lobes and are best followed across more than one plane.

5Posterior fossa

Lower slices show the pons, medulla, fourth ventricle, cerebellar hemispheres, vermis, cerebellopontine angles, and internal auditory canal regions.

CEREBRAL LOBESUse position to separate them

Frontal is anterior, occipital is posterior, temporal is inferolateral, and parietal is superior and posterior to the frontal lobe. Boundaries are easier to follow across multiple planes.

VENTRICLESFollow the CSF pathway

Lateral ventricles connect to the third ventricle, then the cerebral aqueduct, fourth ventricle, and subarachnoid spaces.

BRAINSTEMThree connected levels

The midbrain is superior, the pons is central and rounded, and the medulla continues inferiorly toward the cervical spinal cord.

CEREBELLUMPosterior to the brainstem

The cerebellar hemispheres lie on either side of the midline vermis. The fourth ventricle sits between the brainstem and cerebellum.

03HEAD AND NECK

MOVE THROUGH COMPARTMENTS

The skull base connects the brain to the face and neck.

SELLA AND PARASELLAR REGIONStart with the pituitary

The pituitary gland sits in the sella. The cavernous sinuses and internal carotid artery segments lie to either side. The optic pathways are superior and anterior to the sellar region.

ORBITSFollow the globe to the optic nerve

Identify the globes, lenses, optic nerves, extraocular muscles, orbital fat, and orbital apices. Compare the two sides while checking the image labels.

SINUSES AND NASAL CAVITYAir spaces create strong boundaries

Find the frontal, ethmoid, sphenoid, and maxillary sinuses, then the nasal septum and turbinates. Air and cortical bone usually have very low signal on routine MRI.

ORAL CAVITY AND PHARYNXUse the airway as a central landmark

Follow the tongue, floor of mouth, soft palate, nasopharynx, oropharynx, hypopharynx, and surrounding deep spaces.

SALIVARY AND THYROID GLANDSKnow their expected locations

The parotid glands sit lateral and posterior to the mandibular rami. The submandibular glands lie beneath the mandible. The thyroid lobes sit beside the upper trachea.

VESSELS, MUSCLES, AND NODESTrace them instead of naming one slice

Follow the carotid arteries and jugular veins through the neck. Use the sternocleidomastoid muscles, vertebrae, airway, and salivary glands to organize nodal and deep neck regions.

COMPARE SIDES, THEN KEEP SCROLLING

Many head and neck structures are paired, so symmetry is a helpful starting point. It is not proof that everything is normal. Normal asymmetry, patient rotation, swallowing, dental artifact, flow, and partial volume can change the appearance. Confirm findings across neighboring slices and planes.

04REMEMBER

USE S.I.D.E.S.

Orient first, then build the map.

SStart with the sequence

Know whether you are viewing T1, T2, FLAIR, diffusion, susceptibility, or a postcontrast series.

IIdentify plane and labels

Confirm the imaging plane and the patient's right, left, anterior, and posterior.

DDivide at the midline

Use the falx, ventricles, brainstem, airway, vertebral column, or another central structure.

EEstablish compartments

Separate cerebrum, posterior fossa, skull base, orbits, face, airway, glands, vessels, and neck spaces.

SScroll and compare sides

Follow structures through the stack and compare corresponding regions without assuming perfect symmetry.

SEQUENCELABELSMIDLINECOMPARTMENTSCROLL

Remember: Use both S.I.D.E.S. before deciding what is in the middle.

05APPLY

CHECK YOUR ANATOMY MAP

Choose the best landmark or relationship.

Which structure sits between the brainstem and the cerebellum?

The fourth ventricle. It is a useful posterior fossa landmark and part of the cerebrospinal fluid pathway.

Why can you not identify anatomy by brightness alone?

Signal changes with the sequence and tissue properties. Use location, shape, connections, neighboring structures, and multiple planes along with signal behavior.

You see the pituitary gland in the sella. Which important region lies to either side?

The cavernous sinuses and internal carotid artery segments lie lateral to the sella. The exact relationships should be followed across thin slices and multiple planes.

Which landmarks help organize the lower neck?

The airway, thyroid gland, carotid arteries, jugular veins, sternocleidomastoid muscles, vertebrae, spinal canal, and paired soft tissues provide a useful framework.

Why should a learner compare both sides but avoid assuming they must be identical?

Comparison can reveal a difference, but normal asymmetry, positioning, motion, flow, partial volume, and artifact can also change appearance. Keep scrolling and use the complete study.

LESSON 47 COMPLETE

You can move from the cerebrum through the skull base and neck using major landmarks, compartments, and anatomical relationships.

Educational references

This lesson is an anatomy overview for education. It does not replace a complete anatomy reference, facility protocol, radiologist interpretation, or clinical diagnosis. Anatomy and signal appearance should be evaluated across the complete study.