IN COMPUTED TOMOGRAPHY Soft Tissue Neck IN COMPUTED TOMOGRAPHY Frank Cairo R.T. ( R ) ( CT ) ( MR )

Learning Objectives To describe clinical indications for C.T. examinations of the neck soft tissue. To understand and recognize anatomy and landmarks. To show the proper scan protocols and procedures.

TOPICS Gross anatomy Neck anatomy facts Patient prep Indications Scan protocols Soft tissue neck slides

Gross Anatomy

Hyoid Bone A horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage Level with the third cervical vertebra (C3) behind The hyoid is only distantly articulated to other bones by muscles or ligaments

Hyoid Bone

Hyoid Bone

Thyroid Cartliage Know as the Adams apple Largest and most superior in the neck Level with C3-4 protect the vocal cords Does not make a ring around trachea

Thyroid Cartliage

Cricoid Cartliage At the level of C6 Makes a ring around trachea Applies attachments for muscles and ligaments

Cricoid Cartliage

Thyroid Gland Largest gland in the neck Has 2 lobes connected by the isthmus Sometimes had pyramidal lobe  Controls how quickly the body uses energy, makes proteins, and controls how sensitive the body is to other hormones Produces thyroid hormones

Thyroid Gland

Carotid Anatomy

Carotid Artery

Veins of the neck

Veins of the neck

Neck Circulation 1- rt common carotid artery 2- rt internal jugular vein 3- rt.subclavian artery 4- brachiocephalic artery 5- rt and lt brachiocephalic vein 6- SVC 7- lt common carotid artery 8- lt internal jugular vein 9- lt.subclavian artery 10 – arotic arch

Lymph Nodes

Lymph Nodes

Salivary Glands  exocrine glands, glands with ducts, that produce saliva Saliva for chemical digestion 3 main glands and several minor Parotid, Submandibular, and Sublingual

Salivary Glands

Salivary Glands

Airway

General Imaging Methods—Neck Performed supine with neck slightly extended Most often done in helical mode IV contrast is used, unless contraindicated Split-bolus injection technique is used by some institutions The goal is to allow sufficient time after contrast administration for mucosa, lymph nodes, and pathologic tissue to enhance, yet acquire images while the vasculature remains opacified

Neck Anatomy Facts Neck broken into 3 compartments Visceral Vascular Contains organs Vascular Contains arteries and veins Muscular Neck muscles Landmarks Larynx c3-c6 Cricoid cartilage c5-c6 Carina T4-T5 Carotid bifurcation c3-c4 Thyroid cartilage c3-c4

Indications Diagnosis of neoplasms Infections and abscesses Thyroid mass Salivary gland disorders Vocal cord disorders

Patient Preparation If exam is done with I.V. contrast patient must be NPO 4-6 hours Lab work for I.V. contrast exams Follow all routine precautions for contrast

SINUSES COLLIMATION 0.75mm SLICE THICKNESS 3-5MM FOV 14-20 CM PITCH 1.0 WINDOW 450/30 NECK 4000/300 BONE 16X0.75 FEED/ROTATION 12 MM INJECTION 100-120 ml @ 2-3ml/sec delay 25-30 sec

Soft Tissue Neck 1- SVC 2- Brachiocephalic Artery 3- Lt. Common Carotid 4- Lt. Subclavian Artery 2 1 3 4

Soft Tissue Neck 1- Thyroid Gland 2- Common Carotid 3 1- Thyroid Gland 2- Common Carotid 3- Internal Jugular 4- Verterbral 5- Rt Subclavian 5 4

Bifurcation Above Below cc Ec cc Ic

Neck 1- Internal Juglar vein 2- Submandibular Gland 3 4 5 1- Internal Juglar vein 2- Submandibular Gland 3- Carotid Biufcuation 4- Hyoid Bone 5- epiglottis 6- Vertebral Artery 2 6 1

Neck 1- Vertevbral Artery

Salivary Gland 1- Parotid Gland 1

Salivary Gland 1- Submandibular Gland 1

Neck 1- Basilar Artery 2- Internal Carotid

Soft tissue neck