105 Diagnostic imaging of the larynx Flashcards
The airway at the level of the TVF?
Rima glottidis
Produces a 3D view of the tracheal airway lumen by reconstructing 2D data, used for non-invasive visualisation of the airways
MDCT (Multi-row detector CT) / Virtual laryngoscopy
Gold standard in detection and localization of primary subsites of laryngeal carcinomas
Direct laryngoscopy
Causative agent of epiglottitis/supraglottitis
H. influenza
Plain film radiographic presentation of epiglottitis
Thumb’s sign
Percent of children with subglottic narrowing associated with epiglottitis
25%
Radiographic view to request to assess epiglottitis?
Lateral view
Possible complication of excessive manipulation of patients with epiglottitis?
Glottic spasm
Other factors that may cause enlargement of the epiglottis? give atleast 2.
Foreign body irritation, burns, cysts, neoplasms (lymphoma), granulomatous diseases (sarcoidosis, tuberculosis, Wegener granulomatosis), angioneurotic edema
Inflammation of the subglottic larynx usually caused by parainfluenza virus type 1?
Croup
Causative agent for croup?
parainfluenza virus type 1
Radiographic view to assess croup?
Frontal view
Radiographic finding in croup?
subglottic airway narrowing or “pencilling’ of the airway
Variant of croup that is characterised by diffuse inflammation of the larynx, trachea, and bronchi with adherent exudate and mucus on the surface of the upper tracheal mucosa
Membranous croup
Radiographic finding for membranous croup?
subglottic narrowing and multiple tracheal soft tissue excrescences
The deep neck space that lies posterior to the larynx between the middle and deep layers of the deep cervical fascia?
Retropharyngeal space
Extent of the retropharyngeal space
Skull base to mediastinum
Possible causes of retropharyngeal abscess?
Infection of the retropharyngeal LN sec to URTI, perforation of the pharynx or upper esophagus by a foreign body
Radiographic findings in retropharyngeal abscess?
Fixed thickening of the retropharyngeal soft tissues, anterior displacement of the airway, reversal of normal cervical lordosis, and occasionally gas bubbles within the abscess
The retropharyngeal space should not exceed ___mm at the most anterior aspect of C2 to the posterior pharyngeal wall
7
At C6, the thickness of the retropharyngeal tissues should not be greater than __ mm in children and __mm in adults
14, 22
Diagnostic modality used to detect retropharyngeal abscess
CT or MRI
Presentation of retropharyngeal abscess in CT and MRI
CT - Hypodense
T1 weighted MRI - hypointense
T2 weighted MRI - hypertintense
Also known as congenital flaccid larynx
Laryngomalacia
Imaging findings consistent with laryngomalacia?
Hypopharyngeal overdistention with associated collapse of the aryepiglottic folds and epiglottis on inspiration.
Cause of vocal fold paralysis
any process that involves the vagus nerve or its recurrent laryngeal branch between the jugular foramen and its entrance into the larynx
Percentage of unilateral vocal fold paralysis?
75%
Percentage of peripheral cause of VF paralysis?
90%
Where does the left recurrent laryngeal nerve loop under?
aortic arch
Where does the right recurrent laryngeal nerve loop under?
right subclavian artery
Diagnosis of abnormal vocal fold motion?
Laryngoscopy
