Procedures - Neck

Question 1

What type of scan acquisition is used for soft tissue neck scans?

Answer 1

Helical axial plane

Question 2

What is the anatomical scan range for a CT soft tissue neck?

Answer 2

Superior orbital rim through the lung apex

Question 3

From the superior orbital rim to the hard palate, what should the gantry angle be parallel to?

Answer 3

Hard palate

Question 4

What should the gantry angle be parallel to from hard palate through the lung apex?

Answer 4

Mandibular body

Question 5

The two scans (superior orbital rim to hard palate and hard palate to the lung apex) should overlap to include what?

Answer 5

Posterior skull base and neck

Question 6

When the patient lies supine with the arms relaxed caudally for a CT soft tissue neck, what is reduced in the scan?

Answer 6

Artifact from broadened shoulders

Question 7

What scan setting increases the mAs through the lower neck and thoracic inlet as patient dimension increases towards the shoulders?

Answer 7

Automated tube current modulation

Question 8

What is the average slice thickness range for a ct soft tissue neck?

Answer 8

3-5mm

Question 9

What size sections are acquired for exams of the larynx or CTA of neck vasculature?

Answer 9

Thinner (0.5-2mm)

Question 10

What size SFOV is required to accommodate the variation in part size as the scan progresses from the skull base through the thoracic inlet?

Answer 10

Medium to large

Question 11

What size DFOV is needed for a CT soft tissue scan?

Answer 11

18-25cm

Question 12

What is the WW and WL for soft tissue algorithm on a CT soft

Tissue scan?

Answer 12

WL 50 and WW 400

Question 13

What is the WW and WL for a bone algorithm used in ct soft tissue?

Answer 13

WL 300 and WW 2,000

Question 14

What breathing and swallowing instruction are given to the patient for a ct soft tissue scan to reduce artifact from motion?

Answer 14

Breathe quietly and suspend swallowing

Question 15

What are clinical indications of a ct soft tissue neck?

Answer 15

Inflamed or swollen glands
Infection of abscess
Malignant neoplasms like- carcinoma, sarcoma, and parotid gland tumor
Benign masses like cysts and lipomas
Lymphadenopathy
Trauma
Endocrine pathology involving thyroid and parathyroid glands

Question 16

How is the patient positioned for a ct soft tissue of the larynx exam?

Answer 16

Supine with head extended back

Question 17

Why should the patient’s head be extended backwards for a ct of the larynx?

Answer 17

To place the long axis of the larynx perpendicular to the CT axial plane.

Question 18

When the ct axial plane is perpendicular to the larynx, the axial plane is also parallel to what anatomical structure?

Answer 18

True vocal cords

Question 19

What is the scan range for helical acquisition for ct or the larynx?

Answer 19

Above the hyoid bone through the cricoid cartilage

Question 20

What size slice thickness is needed for CT of the larynx?

Answer 20

Thin (0.5-2.0mm)

Question 21

What technique is used to better visualize the true vocal cords during a ct of the larynx?

Answer 21

Suspended respiration / breath hold

Question 22

What technique may be used to demonstrate abnormal mobility of the vocal cords and involves making an EEE sound during the entire scan length?

Answer 22

Phonation

Question 23

What type of window setting is used for a ct larynx and what’s the WW and WL?

Answer 23

Wide;

WL -300 and WW 1,000

Question 24

What type of exam of the nasopharyngeal and larynx may also be performed for evaluation of inflammatory processes and vocal cord lesions?

Answer 24

Virtual endoscopic CT exams