Head And Neck

Front 1

1. What are the benign causes of lymph node enlargement in the head and neck?
2. What are the malignant causes of lymph node enlargement in the head and neck?
3. Lymphoid hyperplasia is most commonly seen at which sites?

Back 1

1.
- Chronic inflammation and irritation (smokers)
- HIV positivity
- Mononucleosis (chronic Epstein-Barr virus [EBV] infection)
- Youth (<20 to 30 years old)
2.
- Lymphoma
- Mets
3. The findings of lymphoid hyperplasia are most commonly seen in the adenoids, nodes, palatine tonsils, and lingual tonsils (in descending order).

Front 2

What are the different types of Le Fort fractures?

Back 2

- All forms are associated with facial dissociation 2/2 bilateral fxs.
- ALL Le Fort fractures involve fractures of the PTERYGOID PLATES.
1. Le Fort I fracture:
- involves the lower maxilla below the orbital floor.
- +\-extension into maxillary sinuses.
- inferior portion of the maxilla below the fracture line is dissociated from the remainder of the facial bones.
2. Le Fort II fractures:
- fracture is pyramidal in shape, involving bilateral maxilla, and converging superiorly and medially through the inferior and medial orbital walls and nasal bridge.
- nasal bridge and maxilla below the fracture are disassociated from the remainder of the facial bones.
3. Le Fort III fractures:
- result in complete craniofacial disassociation.
- fractures of bilateral zygomaticofrontal sutures, nasofrontal sutures, and lateral, medial, and inferior orbital walls.

Front 3

Branchial cleft cysts:

Back 3

1ST BRANCHIAL CLEFT CYST:
- 2nd MC type of branchial cleft cyst.
- May occur anywhere from the external auditory canal to the angle of the mandible, including within the parotid.
- May become infected following an external ear infection.

2ND BRANCHIAL CLEFT CYST:
- Tract arises from the palatine tonsils.
- Anterior to SCM, impinges upon posterior aspect of submandibular gland, and lateral to the carotid sheath.

3RD BRANCHIAL CLEFT CYST:
- very rare
- Tract is connected to the lateral aspect of the upper pyriform sinus.
- Presents below the level of the 2nd branchial cleft cyst.

4TH BRANCHIAL CLEFT CYST:
- very rare
- presents like a thyroid abscess.

NOTE: Do not confuse branchial cleft cysts with cystic mets (papillary thyroid CA and SCC nodes can be entirely cystic).

Front 4

Thyroglossal duct cyst:

Back 4

- Midline cystic mass that is closely associated with the hyoid bone. (PEARL: any cystic structure closely associated with the hyoid bone (may even by lateral) is TGD until proven otherwise).

- If there is any enhancing nodularity within the cystic mass, raise the question of papillary thyroid cancer.
- Below the level of the hyoid bone, the thryoglossal duct becomes lateral and resides within the strap muscles.
- If a cyst of the TGD develops immediately below the hyoid bone, it bulges the thyrohyoid membrane posteriorly. In this location it can mimic a pre-epiglottic cyst.
- Sistrung procedure is done which involves removing body of the hyoid bone.

Front 5

Lingual thyroid

Back 5

- Located at the level of the foramen cecum in the midline of the tongue.
- Ectopic thyroid tissue will occur in the course of the thyroglossal duct cyst.

PEARL: Always look at the thyroid bed in pts w/ lingual tonsil as 80% of pts w/ lingual tonsil will not have any thyroid tissue in the thyroid bed.

Front 6

Goiter

Back 6

- Thyroid goiter can extend in a substernal, mediastinal, or in the retropharyngeal space.
- Good report about thyroid gotier: There is a multinodular goiter with right sided tracheal deviation. starting 1.5 cm below the level of the cricoid and extending 2 cm inferiorly. There is a 40% cross sectional narrowing of the airway lumen.

Front 7

Dermoid/Epdidermoid cysts

Back 7

- Common locations: Orbit (centered adjacent to sutures), bridge of nose (associated with dermal sinus tract), floor of mouth.
- Look for low attenuation (fat) within the lesion. Epidermoid cysts have reduced diffusion.
- May have a "bag of marble" appearance on T1WIs due to globlets of fat.

Front 8

Orbital floor blowout fracture

Back 8

- 2/2 direct blow to the globe.
- Increased orbital pressure is trasmitted to the thin orbital floor resulting in fx
- Fracture fragment may protrude inferiorly into the maxillary sinus with a trapdoor appearance.
- Intraorbital fat is displaced inferiorly into the maxillary sinus producing the "TEAR DROP SIGN"
- Air-fluid level within the sinus due to hemorrhage.
- Inferior rectus muscle may be displaced inferiorly resulting in muscle entrapment.

Front 9

Tripod fracture

Back 9

- 2/2 direct blow to the zygomatic bone
- Fractures involving the zygomatic arch, inferior orbital wall, and lateral orbital wall.
- Results in dissociation of anterior zygoma from the remainder of the facial bones.

Front 10

Pharyngeal mucosal space mass:

Back 10

SQUAMOUS CELL CARCINOMA:
- MC primary malignancy of H/N.
- commonly originates in the nasopharynx and oropharynx.
- arises from the FOSSA OF ROSENMUELLER.
- may present with NASAL OBSTRUCTION or HEARING LOSS due to **obstruction of eustachian tube and subsequent accumulation of fluid in the middle ear cavity and mastoid air cells**.
- Ill-defined heterogeneous enhancing mass.
- look for necrotic cervical lymph nodes
LYMPHOMA:
- may involve pharyngeal mucosa and appear similar to SCC.
- constitutional sxs and global LAD if lymphoma is systemic.
- If not systemic, look for multiple enlarged cervical lymph nodes without necrosis.
MINOR SALIVARY GLAND TUMOR:
- may be benign (pleomorphic adenoma) or malignant (mucoepidermoid).
- mimic SCC or lymphoma in their appearance.
- METS and associated LAD is UNCOMMON.
INFECTION/ABSCESS:
- fever + sore throat
- 2/2 adenoidal/tonsillar infections.
- Tonsillitis = striated enhancement in a "tigroid" pattern without focal fluid collection.
- Tonsillitis will progress to abscess formation with rim enhancement.
- prompt treatment to prevent retropharyngeal spread, which may spread to mediastinum.
THORNWALDT CYST:
- notochordal remnant within nasopharynx.
- cystic, midline structure situated b/w the longus colli muscles.
- variable amt of protein content determines imaging appearance.

Front 11

Masticator space mass

Back 11

INFECTION/ABSCESS:
- most infections evolve from dental disease.
- starts as cellulitis --> abscess
- osteomyelitis
- look for bone erosion, abnormal marrow SI on MRI, drainable abscesses.
SARCOMA:
- may arise from bone (chondro-, osteo-, Ewing sarcoma) or muscle (rhabdomyosarcoma). NOTE: rhabdomyosarcoma is more common in chidren.
VENOLYMPHATIC MALFORMATION:
- hemangioma or lymphangioma
- can be multicompartmental as they are developmental lesions
- Capillary hemangiomas (pneumonic: capillaries are small and thus capillary hemangiomas occur in infants). Common in infancy, naturally regress.
- Cavernous hemangiomas and lymphangiomas enlarge with age and can cause compressive sxs.
- Look for *phleboliths in hemangiomas.
NERVE SHEATH TUMOR:
- involve the mandibular division of the trigeminal nerve.
- schwannomas are more heterogeneous with cystic and solid components; whereas, neurofibromas are more homogeneous.

Front 12

Carotid space mass

Back 12

PARAGANGLIOMA:
- arise from neural crest cells
- rule of 10s: 10% bilateral, 10% malignant
- Carotid body tumor: located at the level of the CCA bifurcation results in splaying of the internal and external carotid artery.
- Glomus vagale tumor: located superior to CCA bifurcation. Displaces the ICA anteriorly.
- Highly vascular tumors with calcifications and flow voids resulting in SALT AND PEPPER appearance.
- associated with MEN syndromes.
NERVE SHEATH TUMOR:
- typically arise from the vagus nerve; however when more superior in the neck, it may arise from other CNs.
VASCULAR ABNORMALITY:
- Aneurysms/ Pseudoaneurysms
- Thrombosis of IJV from previous line placement.
LYMPHADENOPATHY:

Front 13

Clival mass

Back 13

- Mets (breast, lung, prostate)
- Myeloma
- Chordoma (look for an involved pituitary gland)
- Chondrosarcoma (look for calcifications in rings and arcs; off-midline, MC location = petro-occipital synchondroses)
- Invasive pituitary macroadenoma
- SCC of sphenoid sinus
- Meningioma

Front 14

Vascular injury to the neck

Back 14

- Dissection: 2/2 intimal injury. Can be complicated by pseudoaneurysm formation, thromboembolic disease, or occlusion. TX = anticoagulation.
- Pseudoaneurysm
- AVF: direct communication between the artery and vein typically due to penetrating injury.

Front 15

Floor of the mouth mass

Back 15

SQUAMOUS CELL CA:
- MC neoplasm of the floor of the mouth
- highly associated with tobacco usage
- common locations include base of tongue and palate
- NOTE: mylohyoid divides the floor of the mouth into sublingual space and submandibular space.
- look for ill-defined enhancing mass associated with necrotic lymphadenopathy.
INFECTION/ABSCESS
- mc due to dental procedures or infections.
- Lugwig angina = severe, life threatening infection with abscess formation involving both the sublingual and submandibular spaces.
- Sublingual space abscess = If unilateral, the fluid collection is superomedial to mylohyoid muscle; if bilateral, horseshoe-shaped fluid collection with anterior "isthmus".
- Submandibular space abscess: Fluid collection inferolateral to mylohyoid muscle
- Root of tongue abscess: Midline fluid collection between genioglossus muscles (mimics midline dermoid/epidermoid).
RANULA:
- mucus retention cyst of the salivary glands in the floor of the mouth
- If confined to sublingual space = simple ranula
- If extends below the mylohyoid muscle into submandibular space = diving ranula.
- follow fluid attenuation and signal intensity. Peripheral enhancement suggests infection.
CONGENITAL THYROID LESION:
- Lingual thyroid: failure of the thyroid to descend. In most cases, this is the only fxnl thyroid tissue
- Thyroglossal cyst: majority are midline and infrahyoid.
VENOLYMPHATIC MALFORMATION:
- Hemangiomas and lymphangiomas may occur in the floor of the mouth and involve the tongue.
DERMOID/EPIDERMOID CYST:
- typically cystic, circumscribed, fat containing lesions.
- may mimic ranula if no fat is present.
- **Epidermoid cyst will demonstrate restricted diffusion.

Front 16

Cystic neck mass

Back 16

CONGENITAL CYST
- MC = thyroglossal duct cyst = medial neck
- Branchial cleft cyst = lateral neck
ABSCESS
- can occur anywhere but typically occur within peritonsillar or retropharyngeal regions.
CYSTIC LYMPH NODE:
- may be 2/2 local spread of infection or malignant process (SCC and papillary thyroid cancer)
LYMPHATIC MALFORMATION:
- MC = cystic hygroma
- multiseptated cystic lesion with fluid-fluid levels from hemorrhage
- associated with Down, Turner, and fetal alcohol syndrome.
CYSTIC NERVE SHEATH TUMOR:
- Schwannomas within the carotid sheath when cystic can mimic an infected brachial cleft cyst.
LARYNGOCELE:
- internal, external, or mixed

Front 17

Jugular foramen mass

Back 17

MENINGIOMA
- look for hyperostosis of surrounding bones
- hyperdense mass on CT with calcifications and avid enhancement
SCHWANNOMA
- MC arise from glassopharyngeal nerve
- may compress the ipsilateral jugular vein or sigmoid sinus.
PARAGANGLIOMA
- AKA glomus juguare.
- highly vascular with flow voids
- associated with jugular vein invasion and intraluminal growth.
METS/MYELOMA
DEHISCENT JUGULAR BULB:
- If jugular bulb is above the inferior margin of the round window, it is considered high riding.

Front 18

Jaw Lesions

Back 18

AMELOBLASTOMA:
- Expansile multiloculated or multilobulated mixed cystic & solid mass in posterior mandible
- associated with unerupted molar.
ODONTOGENIC KERATOCYST:
- Mandible > maxilla
- If multiple, consider basal cell nevus syndrome
- Can be uni- or multilocular cystic lesion
- may be associated with an unerupted molar, but not crown.
DENTIGEROUS CYST:
- more common in mandible > maxilla
- well-defined expansile unilocular cyst
- incorporating CROWN of unerupted tooth.
PERIAPICAL LUCENCY:
- associated with carious tooth.
ANEURYSMAL BONE CYST:

Front 19

1. What are the different kinds of glomus tumors (paragangliomas) that occur in the head and neck?
2. What is the appearance of glomus tumors?

Back 19

- Carotid body tumor: carotid space mass at the level of the CCA bifurcation.
- Glomus vagale: carotid space mass near the nodosa ganglion of the vagal nerve. Above the level of the carotid body tumor but below the level of the jugular foramen.
- Glomus jugulare: jugular foramen mass that presents with pulsatile tinnitus.
- Glomus tympanicum: cochlear promontory

2. Intense enhancement with salt and pepper appearance on MRI due to flow voids.

Front 20

Glomus tympanicum

Back 20

- Arises from the cochlear promontory in the middle ear
- Seldom erode bone, hypervascular