Head and Neck

The Head and Neck


The brain may be divided into three parts: the cerebrum, brainstem, and cerebellum(1).

The cerebrum is in front of the brain. It has two primary parts: the right and left hemispheres. The cerebrum is responsible for body temperature, coordination and initiation of movement, hearing, touch, vision, judgment, problem-solving, reasoning, learning, and emotions(2).

Meanwhile, the brainstem is made up of the midbrain, the medulla, and the pons. Brainstem functions include transmissions of sensory messages, mouth and eye movement, involuntary muscle movements, sneezing, coughing, hunger, respirations, consciousness, cardiac function, body temperature, swallowing, and vomiting(3).

Lastly, the cerebellum or the back of the brain is responsible for coordinating voluntary muscle movements and maintaining balance, posture, and equilibrium(4).

Cranial Nerves

Cranial nerves are nerves connected to the brain. Below is the list of cranial nerves in the body(5):

  • Olfactory (signals sensory information related to smell)
  • Optic (transmits visual sensory impulses)
  • Oculomotor (responsible for eyelid movements)
  • Trochlear (responsible for the movements of the eye muscle trochlea)
  • Trigeminal (transmits signals to support face and motor functions)
  • Abducent (responsible for the movement of the eye muscle lateral rectus)
  • Facial (controls facial expression)
  • Vestibulocochlear (sends sound and equilibrium sensory information)
  • Glossopharyngeal (signals sensory information related to the back of the mouth)
  • Vagus (responsible for signals from the heart, lungs, and digestive tract)
  • Accessory (responsible for motor function)
  • Hypoglossal (responsible for the tongue movement)


Thyroid Glands

The thyroid gland is an organ in the neck covered by a fibrous capsule and a sheath called deep cervical fascia(6).

The gland consists of right and left lobes, each of which has an apex ascending between the neck muscle sternothyroid and the pharynx (the tube behind the mouth)(7).

A group of muscles, called infrahyoid muscles, covers the thyroid gland’s lateral surface in front of the neck(8)

Parathyroid Glands

The parathyroid glands are endocrine organs in the neck outside the thyroid capsule. The glands release hormones called parathyroid hormone or parathormone when the body has low blood calcium levels(9).

Trachea and esophagus

The trachea is located in the neck and partly in the thoracic cavity, which refers to the region between the abdomen and root of the neck(10).

The trachea moistens and warms the air passing through the lungs. The organ also protects the respiratory surface from foreign particle buildup(11).

Meanwhile, the esophagus spans the neck, thorax, and abdomen(12). The organ’s primary function is to deliver food from the pharynx to the stomach(13).

Carotid arteries

The right and left carotid arteries are the main vessels of the head and neck(14).

The external carotid artery supplies blood to external skull structures, the face, and most of the neck. The internal carotid artery distributes blood within the cranial cavity(15).

Radiology of the Head and Neck

Head Magnetic Resonance Imaging

A head MRI (magnetic resonance imaging) is a procedure that uses magnets and radio waves to develop images of the brain and its nerve tissues.

During the procedure, the patient lies down on a narrow slate, which slides into a tube-like scanner.

Some MRI procedures need a special dye, called a contrast agent. The radiologist may recommend the dye to highlight certain areas of the body in the medical images.

A head MRI usually takes 30 to 60 minutes to complete(16).

Head Computed Tomography

A head computed tomography (CT) scan uses X-rays to take medical images of the brain, the skull, sinuses, and eye sockets. 

During the procedure, the patient lies down on a narrow slate that slides into the center of the CT scan machine. 

While inside the scanner, the machine sends out X-rays to take separate images of the body that may be stored, viewed on a computer monitor, or saved to a disc.

A complete head CT scan takes approximately 30 seconds to a few minutes(17).

A physician may suggest a head CT scan to diagnose the following medical conditions(18):

  • Infection in the brain
  • Birth defects
  • Brain tumors
  • Stroke or bleeds in the brain
  • Hydrocephalus (fluid buildup in the skull)
  • Trauma to the head, brain, or face

Skull X-Ray

X-ray is a medical imaging procedure that uses electromagnetic energy beams to produce medical images of the skull. Physicians recommend X-rays for various reasons, including diagnosing infection, tumors, foreign bodies, or bone trauma(19).

The procedure uses external radiation to develop images of the body and its organs in films to diagnose a medical problem. Computers and digital media may also be used instead of films.

Neck Xray

A doctor needs X-rays of the spine to evaluate abnormalities in a patient’s neck, back, and spine.

A physician may order the procedure to diagnose the cause of a patient’s neck pain, broken bones, or other abnormalities(20).

Doctors may recommend other procedures to diagnose neck problems, such as myelography (using a spinal needle to check for problems in the spinal canal), CT scan, bone scan, or MRI scan.

  1. O’Rahilly, R., Müller, M., Carpenter, S., & Swenson, R. (2004) BASIC HUMAN ANATOMY A Regional Study of Human Structure. https://www.dartmouth.edu/~humananatomy/part_3/chapter_17.html
  2. Ibid
  3. Ibid
  4. Ibid
  5. Ibid
  6. Ibid
  7. Ibid
  8. Ibid
  9. National Cancer Institute. Thyroid & Parathyroid Glands. Retrieved from https://training.seer.cancer.gov/anatomy/endocrine/glands/thyroid.html
  10. Kudzinskas, A. & Callahan, A. (2020). Anatomy, Thorax. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK557710/
  11. Encyclopedia Britannica. Trachea. Retrieved from https://www.britannica.com/science/trachea
  12. R, O’Rahilly, et al. Op cit.
  13. Colorado State University. The Esophagus. Retrieved from http://www.vivo.colostate.edu/hbooks/pathphys/digestion/pregastric/esophagus.html
  14. R, O’Rahilly, et al. Op cit.
  15. Ibid
  16. MedlinePlus. Head MRI. Retrieved from https://medlineplus.gov/ency/article/003791.htm
  17. Mount Sinai Health System. Head CT Scan. Retrieved from https://medlineplus.gov/ency/article/003791.htm
  18. Ibid
  19. Johns Hopkins Medicine, based in Baltimore, Maryland. X-rays of the Skull. Retrieved from https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/xrays-of-the-skull
  20. Johns Hopkins Medicine, based in Baltimore, Maryland. X-rays of the Spine, Neck or Back. Retrieved from https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/xrays-of-the-spine-neck-or-back

foramina of the skull base (CT)

This webpage presents the anatomical structures found on skull base CT. Foramina of the Skull Base The foramina of the skull refer to small openings that allow the passage of nerves and blood vessels(1).  The human skull has various foramina in which cranial nerves, veins, arteries, and other essential structures pass(2). Moreover, the frontal, ethmoid, …

foramina of the skull base (CT) Read More »

CT Scan of the Temporal Bone

This gallery of images presents the anatomy of the temporal bone by means of CT-scan (reconstructions). Computed tomography or CT scan of the temporal bone uses X-ray technology and advanced computer software to generate detailed images of the head. The temporal bones are situated at the skull’s base and sides.  CT scan allows the radiologist …

CT Scan of the Temporal Bone Read More »

Panoramic radiography

There are 32 permanent teeth in the adult. Each quadrant has 2 incisors, 1 canine, 2 premolars, 3 molars. The numbering is done with two numbers: the first number indicates the dial, the second tooth itself: • First number: Maxilla: upper right: 1; upper left 2; Mandible: lower right: 4; lower left: 3. • Second …

Panoramic radiography Read More »

CT of the Orbit: anatomy

This webpage presents the anatomical structures found on orbit CT. Computed tomography (CT) is the standard diagnostic test for evaluating cross-sectional, two– or three-dimensional images of the body(1). Healthcare providers often debate whether CT or magnetic resonance imaging (MRI) of the orbit is more effective in identifying orbital pathology symptoms. Some experts state that age, …

CT of the Orbit: anatomy Read More »

Skull CT anatomy

The sagittal suture is the line where the right and left parietal bone are in contact. The coronal suture is the line where the parietal bone frontal bone and are in contact. The lambdoid suture is a line where the parietal bone occipital bone and are in contact. The lambda is the point where joins …

Skull CT anatomy Read More »

Paranasal sinuses CT anatomy

This web page presents the anatomical structures found on paranasal sinuses CT. Paranasal Sinuses Paranasal sinuses refer to a group of air-filled spaces around the nasal cavity (a system of air channels that connect the nose with the back of the throat)(1). They facilitate the circulation of the air breathed in and out of the …

Paranasal sinuses CT anatomy Read More »

Need more?