Ch 7 Neck Masses + Lymph Nodes Flashcards
List 3 developmental neck cysts?
-Thyroglossal duct cyst
-Branchial cleft cyst
-Cystic hygroma
What is the m/c congenital neck cyst?
Thyroglossal duct cyst (at the infrahyoid level)
Where are thyroglossal duct cysts?
-They develop within the remnant of the thyroglossal duct
-Typically located midline, anywhere from the base of the tongue to the thyroid isthmus
-M/c location is at the infrahyoid level
Thyroglossal duct cysts occur m/c in older or younger pt’s?
Pediatric pt’s (0-10yrs)
What is the clinical presentation of thyroglossal duct cysts?
-Palpable/visible mass on neck
-Dysphagia (difficulty swallowing)
-Pain
Treatment for thyroglossal duct cysts?
Surgery
SF of thyroglossal duct cysts?
-M/c a midline cystic structure (medial to strap muscles)
-Anechoic, internal echoes or complex (often due to infection)
-Typically <3cm
What is the embryonic development of branchial clefts?
-Neck forms from a tube with 4 arches
-Arches develop into head + neck structures
-Pouches are located on the medial (pharynx) side + form the middle ear, tonsils, thymus + parathyroid glands
-Clefts are located b/w arches on the lateral side
(focus on clefts, not pouches)
What do the 4 branchial clefts develop into?
1st: develops into the external auditory canal
2nd-4th: merges to form the cervical sinus, which then obliterates + disappears
List 3 branchial cleft anomalies?
Cysts (m/c): no internal or external communication
Fistula: communicates internally + externally
(b/w pharynx + skin, pt may have fluid leaking from skin on the lateral side of neck)
Sinus: incomplete tract
(similar to a fistula, but is closed on 1 end)
Why do people get branchial cleft anomalies?
B/c there is incomplete obliteration of the cervical sinus
What causes branchial cleft cysts?
-Incomplete obliteration of clefts
-Congenital
Where are the 4 branchial cleft cysts located?
1st: identified on CT either in the auditory canal (type 1) or submandibular area (type 2)
2nd (m/c): along the anterior border of the upper third part of the SCM muscle or adjacent to it
3rd: rare + deep to SCM
4th: rare + variable location
What are branchial cleft cysts?
Lateral neck masses
Clinical presentation of branchial cleft cysts?
-Palpable neck mass
-Tender with infection
Treatment of branchial cleft cysts?
-Antibiotics (to treat infection)
-Surgery
What is a differential diagnosis for branchial cleft cysts?
Other benign cystic lateral neck masses, such as abscesses + necrotic adenopathy/lymph nodes
SF of branchial cleft cysts?
Is variable:
-m/c anechoic
-homogeneous + hypoechoic with internal debris
-heterogeneous
-pseudosolid (l/c)
What are cystic hygromas due to?
-Congenial
-Due to damage or an error in development of the cervical lymphatic system
-Associated with chromosomal abnormalities (such as turner syndrome, trisomy 21 + 18)
M/c location of a cystic hygroma?
Occipital region
(back of neck or on lateral sides of neck)
SF of cystic hygromas?
Multi-loculated, septated, cystic mass at the posterior + lateral side of neck
List other neck pathology?
-Deep neck space infections
-Hematomas
-Cervical lymphadenopathy
What are deep neck spaces referring to?
The compartments created by facial layers in the neck
(it does not mean deep in the body)
What can deep neck space infections progress into?
-Inflammation/phlegmon or an abscess
-They are uncommon but serious as they have high morbidity + mortality risks
(phlegmon = a localized area of acute inflammation in the soft tissues, can progress into an abscess if not treated)
What causes deep neck space infections in adults + children?
Adults: from dental work (odontogenic)
Children: tonsillitis
Other: infection, drugs, post-procedure, trauma, unknown, etc.
What are the 3 m/c spaces for deep neck space infection abscesses to occur?
-Submandibular space
-Retropharyngeal space
-Parapharyngeal space
Clinical presentation of deep neck space infections?
-History of recent dental procedure, recent other infection (such as upper respiratory tract infection) + neck/mouth trauma (surgery or biopsy)
-Pain
-Difficulty swallowing
What is the gold standard for diagnosing deep neck space infections?
CT
What is ultrasound + MRIs role in diagnosing deep neck space infections?
U/s:
-distinguishes phlegmon from an abscess
-evaluates relation to other anatomy
-m/c 1st step before moving to other imaging modalities (b/c is cheaper + has no radiation)
MRI:
-high resolution for assessing the extent (but is more costly + timely)
SF of deep neck space infections?
Is variable
-Abscess appears fluid filled, thick walled + may have air within the collection (due to gas forming bacteria)
-Enlarged + reactive lymph nodes in the adjacent areas
Treatment for deep neck space infections?
Differs for abscess vs phlegmon
-Typically antibiotics
-Sometimes surgery
When would a hematoma occur?
Following trauma or surgery
SF of a hematoma?
-Similar to an abscess, so we must obtain a clinical history
-Depends on the degree of coagulation as it may be cystic, solid or mixed structures
Where are normal lymph nodes located?
-Throughout the cervical chain
-Easily seen in the submandibular, parotid, upper cervical + posterior triangle regions
(level 2a, 2b, 3, 5a + 5b)
Are lymph nodes harder to see in younger or older pt’s?
Older
What is a common site for metastases, lymphoma, lymphadenitis, TB + reactive hyperplasia?
Lymph nodes
Discuss how u/s, CT + MRI are at imaging lymph nodes?
U/s (gold standard):
-Highly sensitive for small nodes (as small as 2mm) + intranodal calcifications
-Is preferred for identifying metastatic nodes from thyroid cancers
CT:
-Less sensitive than u/s for small nodes
MRI:
-Less sensitive for detecting calcifications within nodes
SF of normal lymph nodes?
-Oval (can be round depending on location)
-Hypoechoic cortex (compared to adjacent soft tissue)
-Echogenic fatty hilum
-Hilar vascularity (hard to appreciate in small nodes <5mm)
-Size (m/c 10mm in short axis (AP), but varies with protocols)
Is lymph node size reliable as a sole criteria for lymphadenopathy?
No! It can be helpful in serial studies tho
What is lymphadenopathy?
Swelling of lymph nodes
3 common causes of lymphadenopathy?
-Infection
-Autoimmune
-Neoplastic
SF of lymphadenopathy?
-Round/bulging
-Hypoechoic
-Absent fatty hilum
-Cystic necrosis within
-Enlarged (on serial exams + with mets)
-Mixed/chaotic vascularity
-Mets from PTC (papillary thyroid cancer), calcifications in the nodes is common + lymph nodes will appear hyperechoic
