11. Peds H+N Masses

Question 1

When to use imaging for neck masses: CT vs US vs MRI

Answer 1

US: most common, fastest, cheap, cyst v. mass, localized, can see calcification, no radiation/sedation

CT: fast, more expensive, cyst vs. mass, GOOD BONE DETAIL, good localization, RADIATION, may require sedation

MRI: SLOW, most EXPENSIVE, helps cyst v mass, GOOD SOFT TISSUE DETAIL, localization, MOST OFTEN REQUIRES SEDATION

Question 2

DDx of Midline Masses in Peds (4)

Answer 2

1. Thyroglossal Duct Cyst
2. Dermoid Cyst
3. Lymph Node
4. Ectopic Thyroid Gland

Question 3

Thyroglossal duct (epidemiology, embryology, clinical course, tests, tx)

Answer 3

MOST COMMON congenital anomaly as neck mass (7% population)
Embryology: duct follows path of thyroid gland during descent from back of tongue - duct persists instead of obliterating
Course: tract assoc with HYOID BONE, usually asx, propensity for infection! (Need for ABx +/- I+D), rarely assoc with malignancy
Test: US - cyst; thyroid tests - rule out hypothyroidism (ectopic thyroid)
Tx: SISTRUNK PROCEDURE - remove cyst with portion of hyoid bone - reduce recurrence rate to 2-6%

Question 4

Dermoid Cyst (epidemiology, embryology, presentation, test, tx)

Answer 4

20% of all H+N dermoids
Embryo: trapped epithelial elements (ectoderm/endoderm) along embryonic lines of fusion
Present: Midline/paramedian neck mass (can occur on scalp, nasal dorsum, lateral brow), NO relationship to hyoid, possible hx of infection, but benign, nontender lump
Text: US - thick fluid-filled cyst
Tx: cyst excision (because only SubQ - less risk of airway injury than sistrunk), well encapsulated, characteristic yellowish appearance

Question 5

Give an example of a lateral neck mass in peds

Answer 5

Branchial cleft anomalies (congenital) - cyst, sinus, fistula

Question 6

What organs do you also check if you suspect a branchial anomaly?

Answer 6

Ears and Kidneys

Due to branchio-oto-renal syndrome

Question 7

Branchial Cleft Anomaly (epidemiology, embryology, types, tx)

Answer 7

2nd most common congenital lesion as neck mass (after TGDC)
Embryo: failure of branchial clefts/pouches to obliterate

Cyst: retained epidermal-lined space w/o communication to skin
Sinus: epidermal lined DUCT with internal OR external communication
Fistula: epidermal lined TRACT communicating pharynx TO skin

Tx: Acute - ABx for infection; Definitive - complete surgical excision

Question 8

How are anomalies further classified? Which branch is most common? What does this branch’s arch, pouch, and cleft differentiate to? How do anomalies in this branch present?

Answer 8

Classified by what branch they come from

Second branch anomaly = MOST COMMON (70-90%)

Arch = superior hyoid, stylohyoid ligament, styloid process, stapes, SFM (CN 7 muscles)
Pouch = palatine tonsils
Cleft = cervical sinus = should obliterate

Presentation = pit anterior to SCM, cysts may be recurrent