outline relevant anatomy cases epiglottitis retropharyngeal abscess bacterial tracheitis croup fb...

Lateral Neck X-Ray

Soft Tissues

Mark Bromley PGY4November 19, 2009

Outline

Relevant Anatomy

Cases Epiglottitis Retropharyngeal Abscess Bacterial Tracheitis Croup FB

Test Characteristics

Case 1

4 year old male

Inspiratory stridor

Unwell for past 24 hours

Mom found him in his room with increased work of breathing

When to order films…

Sub-acute presentation

Diagnosis is unclear

Impending airway embarrassment something else

Epiglottitis

Enlarged epiglottis

Loss of valecular airspace

Thickened aryepiglotic folds

Distended hypopharynx

Straightening of the cervical spine

Sensitivity (38-88%) Specificity (78%)

Croup and epiglottitis: a radiologic study. AU Stankiewicz JA; Bowes AK SO Laryngoscope 1985 Oct;95(10):1159-60.

Epiglottitis and croup. AU Sobol SE; Zapata S SO Otolaryngol Clin North Am. 2008 Jun;41(3):551-66, ix.

Adult epiglottitis: the Toronto Hospital experience. AU Solomon P; Weisbrod M; Irish JC; Gullane PJ SO J Otolaryngol. 1998 Dec;27(6):332-6.

Case 1

4 year old male

Inspiratory stridor

Unwell for past 24 hours

Mom found him in his room with increased work of breathing

Retropharyngeal Infection

Widened retropharyngeal space C2 – 7mm or C6 – 14mm (kids) C6 – 22mm (adults)

Reversal of normal cervical lordosis

Foreign body

Air-fluid level

Gas

False Pre-vertebral Swelling

Oblique lateral

Neck flexion

Crying

Case 1

4 year old male

Inspiratory stridor

Unwell for past 24 hours

Mom found him in his room with increased work of breathing

Case 1

3 year old male

Inspiratory stridor

Unwell for past 24 hours

Mom found him in his room with increased work of breathing

Case 1

4 year old male

Inspiratory stridor

Unwell for past 24 hours

Mom found him in his room with increased work of breathing

Foreign Body

Visualization of radiopaque FB

Widened pre-vertebral shadow

Loss of lordosis

Location Esophagus – coronal plane Trachea – sagittal plane (best seen on lateral)

Test Characteristics

Sensitivity Specificity

Epiglottitis 33-88% 78%

Retropharyngeal abscess 80% 100%

Croup

Foreign Body 84%

Questions?

Thank You!

Triple blinded prospective study

100 elective surgery patients

Lateral neck x-ray compared with Mallampati

Anesthesiologist gold standard (grade III or IV)

Results Mallampati sens: 26% spec: 100% Lateral neck film: sens: 100% spec:100%

Adult EpiglottitisRadiographic Criteria

Epiglottic height-to-width ratio >0.6

Epiglottic to C4 vertebral body width ratio >0.33

Aryepiglottic fold to C3 vertebral body width ratio >0.35

Prevertebral soft-tissue to C4 vertebral body width ratio >0.25

Hypopharyngeal airway to C4 vertebral body width ratio >1.5