Pedi Neck Masses and Vascular Anomalies

Question 1

What is the differential diagnosis for a congenital

neck mass?

Answer 1

Lateral neck masses:
● Branchial anomaly
● Laryngocele
● Thymic cyst
● Pseudotumor of infancy
Midline neck masses:
● Thyroglossal duct cyst (most common midline congenital
neck mass)
● Dermoid cyst
● Plunging ranula
● Teratoma
Entire neck:
● Hemangioma
● Lymphatic malformation

Question 2

What congenital neck mass is most commonly
seen in the first 5 years of life as a 1- to 4-cm
midline cystic mass that moves cranially with
tongue protrusion or swallowing and arises from
the foramen cecum?

Answer 2

Thyroglossal duct cyst

Question 3

Where in the neck are thyroglossal duct cysts

found?

Answer 3

About 60% are located adjacent to the hyoid bone, 24% are
between the hyoid bone and base of the tongue, 13% are
between the hyoid and pyramidal lobe of the thyroid gland,
and the remaining 3% are intralingual. Up to 20% of cysts
are slightly off the midline, with a predilection for the left.

Question 4

What is the cause of thyroglossal duct cysts?

Answer 4

Thyroglossal duct cysts form as a persistent epithelial tract
during the descent of the thyroid from the foramen cecum
in the base of the tongue to its final position in the anterior
neck. They rarely undergo neoplastic transformation (1%).

Question 5

Discuss the evaluation of a child in whom a

thyroglossal duct cyst is suspected.

Answer 5

Evaluate for the presence of thyroid tissue in the cyst (45%)
and whether there is functional tissue elsewhere:
● Ultrasound: Median ectopic thyroid tissue would appear
solid on ultrasound.
● Thyroid function tests: Patients with median ectopic
thyroid tissue are frequently hypothyroid, with elevated
thyroid-stimulating hormone (TSH) levels and resultant
hypertrophy of the ectopic thyroid tissue.
● Thyroid scintiscan: This test is performed if the preceding
tests indicate the presence of a median ectopic thyroid to
determine whether there is functional thyroid tissue in
the cyst and elsewhere.

Question 6

What is the procedure for removal of a

thyroglossal duct cyst?

Answer 6

Sistrunk procedure: Stresses removal of the central portion
of the hyoid bone associated with the thyroglossal duct
tract to decrease the risk of recurrence and removal of the
tract to the level of the base of tongue.

Question 7

What is the clinical presentation of a cervical

thymic cyst?

Answer 7

Most occur in the first decade of life as a lateral neck mass,
anterior to the SCM, most commonly to the left; 80 to 90%
are asymptomatic. However, they may enlarge because of
hemorrhage or infection and cause dysphagia, pain,
dysphonia, and dyspnea. They are also known to expand
with the Valsalva maneuver.

Question 8

What are the possible causes of a cervical thymic

cyst?

Answer 8

● Incomplete descent of the thymus into the chest
● Sequestration of thymic tissue foci along the descent
path into the chest
● Failure of the thymopharyngeal duct to involute

Question 9

What is the difference between congenital and

acquired thymic cysts?

Answer 9

● Congenital: These cysts are usually unilobular and

originate from persistent rudiments of the thymopha-
ryngeal duct. They may have epithelium derived from the

thyroid and parathyroid glands because of their close
association during development.
● Acquired: Cysts are multilobular and develop from
degenerated Hassall corpuscles (degenerated epithelial
cells); they are associated with Sjogren syndrome,
apalastic anemia, and acquired immunodeficiency
syndrome (AIDS).

Question 10

What congenital neck mass is a germ cell tumor
made up of ectodermal and mesodermal
elements but has no endodermal elements?

Answer 10

A dermoid cyst, which can contain hair follicles, smooth

muscle, fibroadipose tissue, and sebaceous glands

Question 11

Where do dermoid cysts form?

Answer 11

Along the lines of embryonic fusion

Question 12

How are head and neck dermoid cysts

categorized?

Answer 12

They are categorized by location:
● Periorbital region: Most common in the head and neck;
develop along the naso-optic groove between the
maxillary and mandibular processes

● Nasal dorsum: Develop during ossification of the fronto-
nasal plate

● Submentum/floor of mouth: Region of fusion of the first
and second branchial arches in the midline, most
common location in the neck
● Suprasternal, thyroidal, and suboccipital regions

Question 13

On clinical examination, how can dermoid cysts

be differentiated from thyroglossal duct cysts?

Answer 13

Both most commonly present as painless midline neck
masses. Because of their superficial location and lack of
mesodermal attachments, dermoid cysts do not move with
tongue protrusion or swallowing. Infection of dermoid cysts
is also rare because they have no communication with the
oropharynx.

Question 14

What is the treatment for dermoid cysts?

Answer 14

Surgical excision. If cervical and cannot exclude the
presence of a thyroglossal duct cyst, consider a Sistrunk
procedure.

Question 15

What congenital anomaly arises from embryonic
germinal epithelium of all three types: ectoderm,
mesoderm, and endoderm?

Answer 15

Teratoma

Question 16

What prenatal findings may indicate a cervical

teratoma?

Answer 16

Maternal polyhydramnios: Often diagnosed during the

prenatal or early neonatal period

Question 17

Where do teratomas occur within the head

and neck?

Answer 17

Neck (most common), nasopharynx, oropharynx, and oral

cavity

Question 18

What is the EXIT procedure?

Answer 18

The ex utero intrapartum treatment (EXIT) procedure is a
technique used to establish an airway in neonates with
airway compression from congenital anomalies diagnosed
prenatally. It involves establishing an airway while the
fetoplacental circulation is preserved. The fetus is partially
delivered via a cesarean section, and the airway is then
secured while the fetus remains attached by its umbilical
cord to the placenta.

Question 19

What abnormal dilation or herniation of the
saccule of the larynx can result in an air- (most
often), mucus-, or pus-filled congenital neck
mass, respectively?

Answer 19

Laryngocele, laryngomucocele, laryngopyocele, respectively

Question 20

What is the difference between an internal and

external laryngocele?

Answer 20

● Internal: Dilation lies within the limits of the thyroid
cartilage and is seen as cystic swelling of the aryepiglottic
fold.
● External: Dilation extends beyond the thyroid cartilage in
a cephalad direction to protrude through the thyrohyoid
membrane.
● Combination: These can have internal and external
components.

Question 21

What benign congenital neck mass presents as
a firm, round, nontender mass seen at the
junction of the upper and middle third of the
SCM that typically presents 2 to 3 weeks
after birth?

Answer 21

Pseudotumor of infancy. Also called sternocleidomastoid
tumor of infancy, fibromatosis coli, or congenital muscular
torticollis.

Question 22

What is the natural history of a pseudotumor of

infancy?

Answer 22

It is present 2 to 3 weeks after birth, slowly increases in size
for 2 to 3 months, and then slowly regresses for 4–8
months; 80 to 100% completely resolve by 12 months.
Some benefit is derived from physical therapy.

Question 23

What salivary gland is most commonly associated

with a plunging ranula?

Answer 23

Sublingual gland

Question 24

How do plunging ranulae most often manifest?

Answer 24

Intraoral component appears as a blue dome-shaped lesion
in the floor of mouth, usually on either side of the midline.
The extraoral portion is seen as a submental mass
extending along the inferior border of one side of the
mandible. It is not a true cyst.

Question 25

What are the treatment options for plunging

ranulae?

Answer 25

● Intraoral incision and marsupialization of cyst
● Intraoral excision with removal of sublingual gland
(preferred)
● External cervical approach to identify the cyst, with

dissection through the mylohyoid muscle. In combina-
tion, excision of the sublingual gland can be performed

via an intraoral approach.
● OK-432 intralesional sclerotherapy

Question 26

How do vascular malformations differ clinically

from hemangiomas?

Answer 26

Hemangiomas are typically absent at birth, appear during
infancy, undergo rapid growth within the first year of life,
and then undergo a variable period of involution. Most
vascular malformations are present at birth, demonstrate
growth parallel to the child’s development, and do not
involute over time.

Question 27

How are vascular malformations classified?

Answer 27

Based on the rate of blood flow:

● Low-flow lesions: Capillary malformations, venous mal-
formations, lymphatic malformations, and a combined

type that has a mixture of either two or three of the low-
flow lesions

● High-flow lesions: Arterial malformations and arterio-
venous malformations

Question 28

What type of malformation is located in the
cutaneous superficial vascular plexus, is made
up of capillary and postcapillary venules, and
grows with the individual, typically becoming

darker, nodular, and occasionally leading to hyper-
trophy of the underlying soft and hard tissues

(which can lead to disfigurement)?

Answer 28

Capillary malformation (vascular malformation). Also
known as a port-wine stain, it is commonly associated with
Sturge-Weber syndrome.

Question 29

What syndrome commonly manifests with a triad
of facial dermal capillary malformation, ipsilateral
central nervous system vascular malformation
(leptomeningeal angiomatosis), and vascular
malformation of the choroid in the eye
associated with glaucoma?

Answer 29

Sturge-Weber syndrome

Question 30

How are capillary malformations treated?

Answer 30

The superficial component can be treated with laser
photocoagulation with the pulsed-dye laser (585-nm
wavelength). Surgery ranging from simple excision of
bleeding nodules to wide resection of hypertrophic tissues

with soft tissue reconstruction may be used to treat long-
standing capillary malformations.

Question 31

Describe the manifestation of a capillary

malformation.

Answer 31

Also termed port-wine stain, they are the most common
vascular malformation, are present at birth, and grow in
proportion to body development. They initially appear red
and flat and over time may become more purple. They
rarely involute.

Question 32

What congenital lesion manifests as a bluish
discoloration of the skin or mucosa with a soft
and compressible deep component, which can
swell with Valsalva maneuver or dependent
positioning and has no associated thrill or pulse
on examination?

Answer 32

Venous malformation

Question 33

Where do venous malformations commonly

occur in the head and neck?

Answer 33

Lips and cheeks. Intraosseous venous malformations (“soap
bubble” on radiographs) can occur in the mandible, maxilla,
zygoma, or calvarium.

Question 34

What is the relationship between venous

malformations and coagulopathy?

Answer 34

Venous malformations are commonly associated with
coagulopathy resulting from the tortuous vessels, abnormal
endothelium, and the low-flow characteristics. Tissue
thrombosis can be detected as calcified phleboliths on plain
radiographs or CT scans, as well as elevated D-dimer in the
blood, and often leads to acute and chronic swelling and
pain in the affected area.

Question 35

Discuss the treatment options for venous

malformations.

Answer 35

Surgical resection of well-circumscribed lesions, percuta-
neous sclerotherapy as a primary treatment modality or

adjunct to surgery, and laser therapy, including pulsed-dye
laser, noncontact neodymium-yttrium-aluminum (Nd:YAG)
or potassium titanyl phosphate (KTP) lasers

Question 36

How do lymphatic malformations in the head and

neck manifest?

Answer 36

About 90% are diagnosed before age 2. They often appear
as an intraoral mass or neck mass that is nontender and
may cause functional concerns, such as difficulty with
speech or swallowing or respiratory concerns. They can
rapidly enlarge after infection or trauma caused by bleeding
or swelling and may be diagnosed in utero during routine
prenatal screening.

Question 37

How are lymphatic malformations classified?

Answer 37

Based on the size of the cystic component:
● Macrocystic: Single or multiple cysts at least 2-cm large
● Microcystic: Cysts smaller than 2 cm
● Mixed lesions: At least a 50% macrocystic component

Question 38

How are cervicofacial lymphatic malformations

staged?

Answer 38

● Stage I: Unilateral, infrahyoid
● Stage II: Unilateral, suprahyoid
● Stage III: Unilateral, infrahyoid and suprahyoid
● Stage IV: Bilateral infrahyoid
● Stage V: Bilateral infrahyoid and suprahyoid

Question 39

What is the relationship between the type of
lymphatic malformation and its anatomical
location?

Answer 39

● Facial lymphatic malformations lateral to the lateral
canthal line tend to be macrocystic, whereas medial
midfacial lesions tend to be more mixed.
● Midface involvement is uncommon and usually is
completely microcystic.
● Neck lymphatic malformations are divided into infrahyoid
and suprahyoid.
● Infrahyoid disease is generally macrocystic and suprahyoid
disease is more likely to be microcystic.

Question 40

Discuss the treatment modalities for lymphatic

malformations.

Answer 40

● Surgical resection is most successful in macrocystic
lesions of the posteroinferior neck and parotid regions.
Microcystic and mixed suprahyoid lesions may require
subtotal resection while preserving vital structures.
● Percutaneous sclerotherapy (e.g., doxycycline, OK-432)
may be used as primary control of macrocystic lesions
and as an adjunct to subtotal resection of mixed lesions.
● Carbon dioxide laser resurfacing can be used to control
mucosal microcystic lesions.
● Sclerotherapy with OK-432, a lyophilized, low-virulence
strain of Streptococcus pyogenes, is best for unilateral
macrocystic lesions in the infrahyoid area.
● Observation: Unilocular or nearly unilocular lesions,
especially if they are located in the posteroinferior neck,
may spontaneously resolve.

Question 41

What pathology results from high-flow vascular
malformations that arise from a nidus of blood
vessels that have abnormal precapillary
communication between arteries and veins?

Answer 41

Arteriovenous malformations (AVMs)

Question 42

Describe the presentation of an AVM.

Answer 42

It is present since birth but often expands with trauma or
hormonal changes and is often warm and red or blue with
an audible bruit and palpable thrill.

Question 43

Describe the staging system for AV

malformations (AVMs).

Answer 43

Schobinger staging system
● Stage I (quiescence): Pink-bluish stain, warmth, and AV
shunting on Doppler ultrasound
● Stage II (expansion): Stage I plus enlargement, pulsations,
thrill, bruit, and tortuous/tense veins
● Stage III (destruction): Stage II plus dystrophic skin
changes, ulceration, bleeding, persistent pain, or tissue
necrosis. Bony lytic lesions may occur.
● Stage IV (decompensation): Stage III, plus congestive
heart failure with increased cardiac output and left
ventricle hypertrophy

Question 44

What are the imaging characteristics of AVMs?

Answer 44

● MRI: No enhancement on T2-weighted images and flow
voids on both T1-weighted and T2-weighted images
● Angiography: Dilatation and lengthening of arteries and
early shunting of enlarged veins
● CT: Skeletal involvement

Question 45

Describe the treatment of AVMs.

Answer 45

The best chance at cure is a combination of endovascular

embolization and surgical resection. The target for embo-
lization is the nidus, or the abnormal network of vascular

channels bridging the arterial and venous systems. Embo-
lization can be curative in smaller lesions, palliative in

complicated or unresectable lesions, or preoperative. Coil
embolization is contraindicated.

Question 46

Discuss the causes of hemangiomas of infancy.

Answer 46

Hemangiomas of infancy occur most commonly in the head
and neck and more commonly in girls than in boys (3:1); in
premature infants weighing less than 1200 g, with the risk
increasing by 40% for every 500-g decrease in birth weight;
and in infants born to mothers of advanced maternal age
with a history of chorionic villus sampling.

Question 47

What are the two main types of hemangiomas of

infancy?

Answer 47

● Focal: More common; a tumor-like growth pattern

● Segmental: Less common; diffuse, plaque-like lesion

Question 48

What is the relationship between focal and
segmental hemangiomas of infancy and the
embryologic development of a hemangioma
of the face?

Answer 48

Segmental lesions are thought to occur in embryologic
prominences related to neural crest cells, which influence
vascular patterning.
Focal lesions occur in identifiable patterns associated with
lines of embryonic tissue fusion, such as the central face.

Question 49

What are the phases of hemangiomas of infancy?

Answer 49

● Proliferative phase: Rapid growth from 2 weeks to 1 year

of age
● Involuting phase: Slow regression from 1 to 7 years
● Involuted phase: Complete regression after 8 years of age

Question 50

What vascular tumors reach maximal size at
birth and do not enter into a rapid postnatal
growth phase?

Answer 50

Congenital hemangiomas

Question 51

What are the two types of congenital

hemangiomas?

Answer 51

Two major subgroups exist:
● Rapidly involuting congenital hemangioma (RICH), which
show accelerated regression typically by 1 year of age
● Noninvoluting congenital hemangioma (NICH), which do
not enter an involution stage

Question 52

What diagnostic steps can be taken to
differentiate hemangiomas of infancy from
congenital hemangiomas?

Answer 52

Evaluation of the pattern of proliferation, the pattern of
involution, and, importantly, immunostaining. Infantile
hemangiomas stain positive for glucose transporter 1

(GLUT1) and Lewis Y (LeY), whereas congenital hemangio-
mas (RICH and NICH) do not. Placental microvasculature

also stains positive for these markers.

Question 53

What is PHACE/PHACES syndrome?

Answer 53

PHACE describes the association of facial segmental
hemangiomas of infancy with one or more of the following
anomalies:
P Posterior fossa brain malformations
H Hemangioma, covering > 5 cm of the head/neck
A Arterial anomalies
C Cardiovascular anomalies
E Eye anomalies
PHACES refers to the presence of ventral developmental
defects, specifically sternal defects and/or supraumbilical
raphe.