Head and Neck 4 Flashcards

Question

Where does the frontal sinus drain to?

Answer 1

* frontal sinus * frontal-ethmoidal recess * middle meatus * (joins flow from ipsilateral maxillary sinus)

Answer 2

* **_Follicular thyroid adenoma_** * **commonly found benign neoplasm of the thyroid** consisting of differentiated follicular cells. * It cannot be differentiated from follicular carcinoma on cytologic, sonographic or clinical features alone. * Epidemiology * Follicular thyroid adenoma is more commonly found in **women**, * increases in incidence with * increasing **age** * in regions in which the **diet is iodine deficient**. * **5 times more frequent than follicular carcinomas.** * Pathology * Macroscopically * **round to oval,** * **fibrous capsule that is usually regular and thin**. * between 1 and 3 cm, * cystic degeneration, * haemorrhage, ossification, * calcification and * fibrosis * Cytology * Functioning follicular adenomas occur as a result of a monoclonal expansion of thyroid follicular cells with a high prevalence of activating mutations in the gene for the TSH receptor 1. * Genetics * N-RAS and K-RAS mutations may be present in patients with follicular adenoma and have been implicated in the evolution of follicular adenoma to follicular carcinoma 4. * Subtypes * macrofollicular thyroid adenoma * microfollicular thyroid adenoma * Radiographic features * Ultrasound * Ultrasound features of follicular adenomas share many features with follicular carcinomas. In general follicular thyroid adenomas: * thin peripheral halo * predominantly cystic or mixed cystic and solid lesions * isoechoic or predominantly anechoic * can be homogenous or heterogeneous * absence of internal flow or predominantly peripheral flow indicates is associated with reduced probability of thyroid follicular malignancy

Answer 3

Laryngeal amyloidosis Intraoperative photo demonstrating left well-defined submucosal lesion arising from the left laryngeal ventricle, clear of vocal fold and anterior commissure. Case Discussion The patient underwent cold steel and shaver excision of the laryngeal lesion under general anaesthesia. Histology: numerous deposits of homogenous eosinophilic material which stained salmon pink on congo red and showed apple-green birefringence, confirming amyloidosis. Case discussion Amyloidosis is very rare and represents a heterogeneous group of disorders marked by abnormal protein formation and deposition which can cause organ failure and death. Up to 20% involve the head and neck, the larynx being the most common site of disease, representing 0.2-1.2% of all benign laryngeal tumours. Symptoms depend on the size and specific location of the deposit and may include dysphonia, dysphagia or exertional dyspnoea.

Answer 4

* distribution and impact of nodal spread from NPC is different from other mucosal head and neck cancers and therefore a different N classificaiton is used. * American Joint Committee on Cancer system applies for epithelial cancers (usually **SCC**) of most regions of the head and neck, including: * those of the skin, * maxillary sinus, * nasal cavity and * ethmoid sinus, * oral cavity, * oropharynx, * major salivary glands, * hypopharynx, * larynx, and * unknown primary. * **Notable exclusions of head and neck cancer**s: * are **HPV-related oropharynx** cancer, * **nasopharynx** cancer, * mucosal melanoma, and * thyroid cancers * differentiated, * medullary, or * anaplastic * **_NASOPHARYNGEAL CANCER (NPC)_** * N1: * unilateral nodal mets * above supraclav fossa \<6cm * +/- unilateral or bilateral retropharyngeal nodes \<6cm * N2: * bilateral nodal mets above supraclav fossa \<6cm * N3a * nodal mets \>6cm * N3b * nodal mets extension to supraclav fossa * OTHER SITES (Oral cancer, oropharynx, hypopharynx, larynx): * N1: * met in a single ipsilateral LN \<3cm * N2 * met in a single ipsilat LN \>3 but \<6cm * or in multiple ipsilateral LNs \<6cm * or in bilateral or contralateral LNs \<6 * N2a * mets in a single ipsi LN \>3 but \<6cm * N2b * mets in multiple ipsi LNS \<6 * N2c * Mets in bila or contrala LN \<6 * N3 * mets in a LN \>6cm * N0: no regional LN mets * Nx: LN status cannot be assessed. * Node size in classificaiton refers to greastest dimension.

Answer 5

* Features favoring benign nodules: * **Purely cystic or spongiform nodules** * have a very low risk for malignancy * **Increased echogenicity** * of solid component relative to thyroid parenchyma favors benign nodules * **Smooth** * ****uninterrupted, well-defined, and curvilinear edge * **Halo** * dark rim around nodule periphery * A uniform complete halo has been suggested to favor a benign nodule, but a complete or incomplete halo may nonetheless be seen in 10%–24% of thyroid CAs. * **Comet-tail artifacts** * are seen in **colloid cysts.** * **Macrocalcifications** * (large enough to result in posterior acoustic shadowing) * Depending on pattern may favor benign but can also have an association with malignancy * “Eggshell” calcification favors benign nodule

Answer 6

* Antrochoanal Polyp * Most common type of solitary sinonasal polyp * polypoid mass extending from maxillary sinus to nasal cavity via an enlarged maxillary ostium or accessory ostium * Epid * Most commonly seen in teenagers and young adults * Radiographic Features * Well-defined **dumbbell**-shaped mass extending from maxillary sinus into nasal cavity * Usually low/mucoid central density (may have higher density depending on inspissated component and fungal colonization) * Bone remodeling rather than destroyed * Peripheral enhancement of surrounding mucosa, no central enhancement (unlike inverted papilloma and tumors) * Case courtesy of Dr Roberto Schubert, Radiopaedia.org, rID: 15098

Answer 7

* Can be challenging bc of variable ossificaiton * nonossified parts can have attenuation similar to tumour making interpretation challenging * most reliable criteria used for eval of TC invasion on CT is * erosion * lysis * extralaryngeal spread (tumour on both sides) * Sclerosis is a reactive phenomenon and does not necessarily indicate acutal cartilage invasion by tumour * MRI * can be used to supplement CT. * better at distinguishing nonossified cartilage from tumour * however there is propensity for false positives due to reative edema * invaded cartilage should follow tumour signal on all sequences. * Helps distinguish ture invasion from edema * Dual energy CT may imporve evaluation of TC invasion

Answer 8

* Locations: * Upper glands: * posterior to upper-mid pole of thyroid, * occasionally extend posterior to pharynx or esophagus * (CT useful for evaluation of deep locations) * Lower glands: * posterior and/or lateral to lower pole of thyroid * Ectopic locations: * from angle of mandible * to lower anterior mediastinum; * near hyoid, * arotid sheath, * intrathyroid, prevascular space in mediastinum * the inferior glands follow the descent of the thymus

Answer 9

1. HypoPT * low calcium * high phosphate * low parathyroid hormone * **surgical removal most common** 2. Pseudohypoparathyroidism * low calcium * high phosphate * high parathyroid hormone * **End-organ resistance to PTH (hereditary)** 3. Pseudo-pseudohypoparathyroidism * Only skeletal abnormalities (Albright hereditary osteodystrophy) * normal bloods * skeltal manifesations of Pseudohypoparathyroidism FIG. 1. Typical features of Albright hereditary osteodystrophy. (A) A young woman with characteristic features of AHO; note the short stature, disproportionate shortening of the limbs, obesity, and round face. (B) Radiograph of the AHO patient showing marked shortening of fourth and fifth metacarpals. (C) Archibald sign, the replacement of “knuckles” with “dimples” due to the marked shortening of the metacarpal bones. (D) Brachydactyly of the hand; note thumb sign (Murderer's thumb or potter's thumb) and shortening of the fourth and fifth digits.

Answer 10

* Tracheobronchopathia osteochondroplastica * very rare idiopathic non-neoplastic tracheobronchial abnormality. * Epidemiology * The estimated prevalence on routine bronchoscopy can be up to 0.7%. * It typically affects those in the 5th to 6th decades * male predilection 4. * Clinical presentation * Most patients are asymptomatic. * Those who have symptoms may present with cough, shortness of breath on exertion, wheezing or recurrent respiratory infection. * Haemoptysis can occasionally result from an ulceration of a nodule or an acute infection. * Pathology * There is development of osseous or cartilaginous 1-8 mm 2,3 nodules or both in the submucosa of the trachea and bronchial walls. * They may be either focal or diffuse. * There is characteristic sparing of the posterior membranous portion of the trachea 6. * There are two possible theories of pathogenesis * ecchondrosis and exostosis from cartilage rings * cartilaginous and osseous metaplasia of the elastic tissue in the internal elastic fibrous membrane * Differential diagnosis * tracheobronchial amyloidosis * unlike TO, classically circumferential involvement * may appear as focal or diffuse narrowing * relapsing polychondritis * like TO, spares posterior membranous tracheal wall * more likely smooth, hyperdense mural thickening 10 * patients usually have other clinical findings of cartilaginous inflammation 10

Answer 11

* Type 1: * anterior to SCM * deep to platusma * Type 2 * most common * anterior to SCM * posterior to SMG * Lateral to the carotid sheath * Type 3: * extends between ICA and ECA * may extend to lateral pharyngeal wall * or superior to skull base * Type 4 * adjacent to lateral pharyngeal wall

Answer 12

**Laryngeal Chondrosarcoma** Clinical/Path * Hyaline cartilage origin, not elastic, path grades I-III * 0.5% of laryngeal malignancies, mean 64, M\>F 3.6:1 * Airway compromise * Most low grade, but prognosis good despite grade (except for rare myxoid) * Surgical resection of chondroid lesion usually curative whether benign or malignant

Answer 13

* not true tumour * sequela of inflammatory rhinosinusitis * expansion of fluids in the deeper lamina propria of the SCHNEIDERIAN mucosa in the nasal cavity and paranasal sinuses. * They are the most common expansile lesion in the sinonasal cavity. * Fibrosis and neovascularisation of nasal polyps may occur and can result in a a vascularised polyp that mimics an angiofribroma on pathology

Answer 14

* Hashimoto thyroiditis: * Findings vary depending on stage of disease and extent of involvement (diffuse vs. focal) * Acute: * Focal nodules against normal or altered background of thyroid parenchyma * Diffuse hypoechoic and heterogeneous micronodular pattern involving entire gland * Variable vascularity * this appearance may be described as pseudonodular or a **giraffe pattern.** * Chronic: * Enlarged hypoechoic micronodular gland * Hypervascular if patient is hypothyroid (hypertrophic action of thyroid-stimulating hormone [TSH]); following treatment and normalization of TSH hypervascularity decreases * Atrophic/end-stage: * Small hypoechoic gland with heterogeneous echo pattern * Hypovascular

Answer 15

Laryngeal chondrometaplasia Symptomatic laryngeal chondrometaplasia is a rare entity. Metaplasia is the transformation of one differentiated tissue into another as a response to injury, but the exact etiology of the laryngeal chondrometaplasia is still unknown. The symptomatic laryngeal lesion is usually first discovered by fiber-optic laryngoscopy and subsequently diagnosed by biopsy. Cross-sectional imaging has been increasingly used to assess the exact origin and extent of the lesion.

Answer 16

Hypoparathyroidism * Primary * Idiopathic * autoimmune * absence of parathyroid glands * Rare; associated with * cataracts, * mental retardation, * dental hypoplasia, * obesity, * dwarfism * Secondary * Surgical removal (most common) * radiation * Rarely other causes such as autoimmune disease or other

Answer 17

The maxillary sinus (or antrum of Highmore) is a paired pyramid-shaped paranasal sinus within the maxillary bone. It drains via the maxillary ostium -\> infundibulum -\> hiatus semilunaris -\> middle meatus. It is the largest of the paranasal sinuses.

Answer 18

previous Thyroplasty Pittfall/mimic of vocal cord paralysis/malignancy Teflon. A, Axial CT demonstrates hyperattenuating material in the bilateral vocal folds (arrows) consistent with Teflon injection. B, Axial CT in a different patient status post Teflon injection into the right vocal fold demonstrates a slightly nodular contour (arrowheads) consistent with granuloma formation, a common complication of Teflon.

Answer 19

Clinically Important Anatomic Landmarks and Reporting * Anatomy * Divide parotid into deep and superficial lobes * Deep lobe of the parotid gland extends between the mandibular ramus and styloid process (stylomandibular tunnel) into the prestyloid PPS. * Look at the PPS * absence or presence of a fat plane between normal parotid tissue and the mass may be helpful in distinguishing masses originating in the deep lobe of the parotid from those originating in PPS (or extending there from elsewhere). * In masses arising in the deep lobe of the parotid (majority pleomorphic adenomas), one expects absence of fat tissue plane on some or all slices. * Other features favoring origin in the deep parotid lobe include normal parotid tissue partially wrapped around the mass or extension of mass laterally into stylomandibular tunnel. * Look for the facial nerve * The relationship to the facial nerve is essential for surgical planning. * The expected plane of the facial nerve projects from the stylomastoid foramen anteriorly and inferiorly to the lateral aspect of retromandibular vein (and further anterior over the surface of masseter muscle). * A line drawn in this plane is used to estimate and divide the parotid into superficial and deep lobes. * The relation of tumor to this plane needs to be clearly indicated in the radiologic report.

Answer 20

4th branchial cleft cyst

Answer 21

* posterior ethmoid complex and sphenoid sinus * drain into the sphenoethmoidal recess * superior metaus * nasopharynx

Answer 22

Central giant cell lesions (granuloma) * AKA * Central giant cell lesions (granulomas) * giant cell reparative cysts/granulomas * location * occurs almost exclusively in the mandible, although cases in the skull and maxilla have been reported. * Epidemiology * It is most frequently seen in **young women** (F:M 2:1) and typically presents in the * 2nd and 3rd decades. * Pathology * The lesion consists of non-neoplastic vascular tissue, with giant cells and haemosiderin. * It is thought to occur as a local reparative inflammatory process likely relating to trauma. * Location * Usually located in the anterior part of the jaw. * Radiographic features * Imaging features are generally nonspecific on both CT and MRI * It begins as a small lucent region, and gradually as it enlarges thin trabeculae of bone become apparent, giving it a honeycomb multilocular appearance. * The lesion may demonstrate expansion, root resorption, and erosion through or remodelling of the overlying cortex. * Some authors believe that cherubism (usually considered a form of fibrous dysplasia) is actually a special form of giant cell reparative granulomas 3. * History and etymology * It was first described by Jaffe in 1953 4,5. * Treatment and prognosis * Primary resected surgically. Recurrence rates of up to 15% have been reported. * Differential diagnosis * brown tumour (osteitis fibrosa cystica) * its appearance both radiologically and histologically is very similar to brown tumours of hyperparathyroidism, however patient demographics (and parathyroid function) make the distinction usually simple * ameloblastoma 5 * aneurysmal bone cyst 5 * intracranial tumour 7

Answer 23

Laryngocele * dilatation of the laryngeal saccule * thin walled air or fluid filled cystic lesion * communicating with laryngeal ventricle * if fluid filled, some prefer the term saccular cyst or laryngeal mucocele. * most commonly aquired * glass blowers * wind instruments * COPD * obtruction from tumour * Types of Laryngocele * Internal/simple laryngocele * air or simple fluid filled lesion in the paraglottic space * mixed laryngocele * extralarynfeal extension from paraflottic space through thyrohyoid membrane into low submandibular space * pyolaryngocele * superinfected laryngocele containing pus * secondary laryngocele * glottic or inferior supra glottic lesion obstrucitg the laruyngeal ventricle

Answer 24

* US features that suggesting increased risk of malignant nodules include: * **Predominately solid** * (soft tissue component occupying ≥50% of volume of the nodule) * **Hypoechoic** * relative to surrounding thyroid tissue * **Very hypoechoic** * decreased echogenicity relative to adjacent neck musculature (low sensitivity but high likelihood of malignancy) * **Ill-defined**, **irregular**, or **lobulated** margins * **Taller than wide** shape * (ratio of \>1 AP/transverse diameter) * **Size**: * correlation between nodule size and risk of malignancy controversial: * Increased cancer risk in nodules \>2 cm * Some guidelines (Thyroid Image Reporting and Data System [TIRADS]) do not include size in the scoring system * Others suggest biopsy of nodule \>1–1.5 cm * Increasing trend not to biopsy nodules \<1 cm * **Punctate echogenic** foci or “microcalcifications” * NB: some refer to all punctate echogenic foci in thyroid nodules as microcalcifications, but this is a misnomer, may arise from the back walls of tiny unresolved cysts * **Hypervascular** on Doppler * **Extension** beyond thyroid and invasion of adjacent structures

Answer 25

Parathyroid Adenoma Adenomas may consist of pure or mixed cell types, with the most common variant composed principally of chief cells. seen with MEN 1 syndrome (rare). 80% single, 20% multiple.

Answer 26

sincipital cephalocele Sincipital encephaloceles are congenital herniations of cerebral parenchyma through a cranial defect. There are three main types 1,2: 1. **frontonasal encephalocele (picture)** * ****(~50%) * more common in Asia and Latin America 4 * anterior midline between the nasal and frontal bones, through unobliterated fonticulus frontalis 2. **nasoethmoidal encephalocele** * (30%): * more common in North America 4 * anterior and superomedial nasal cavity in region of/through foramen cecum 3. nasoorbital (nasolateral) encephalocele * inferomedial orbit, * through defect in lacrimal/frontal process of maxillary bone * Meninges, CSF, and/or brain tissue trapped in a mesodermal defect in anterior skull base during embryologic development with intracranial communication, most common in Southeast Asia (occipital cephaloceles more common in North America). * Connects to the intracranial brain. * Complications * Prone to CSF leaks and infections * Other associated congenital abnormalities: * Callosal hypogenesis and interhemispheric lipomas * Neuronal migration abnormalities * Microcephaly * Aqueductal stenosis and hydrocephalus * Colloid or arachnoid cysts * Midline craniofaci Differential diagnosis Consider other midline nasal region lesions, **in particular nasal glioma.**

Answer 27

Juvenile Angiofibroma * Benign but locally invasive nonencapsulated vascular tumor of mesenchymal origin. * Epid * Occurs almost exclusively in young males (age: 10–25 years). * Clinical * Suspect in adolescent male presenting with * nasal obstruction * epistaxis. * Location: * Mass originating/centered in posterior nasal cavity in region of sphenopalatine foramen * Can extend more anteriorly in nasal cavity, into nasopharynx, PPF, or infratemporal fossa; may also extend into sphenoid (60%), maxillary, or ethmoid sinuses * Early invasion of PPF (90%) * Less common sites of extension: inferior orbital fissure, middle cranial fossa via vidian canal or foramen rotundum * * Imaging characteristics: * Lobulated lesion, may have well-circumscribed or infiltrating (larger lesions) margins * May have associated obstructive and inflammatory changes (nonenhancing) * Associated bone remodeling ± destruction * Highly vascular with intense enhancement on CT and MRI * Ipsilateral external carotid and internal maxillary arteries may be enlarged * T2W MRI: intermediate to high signal with flow voids * Angiography: tumor blush * * Pearls * Feeding vessels: * * Internal maxillary and ascending pharyngeal arteries from ECA (most common) * * May have ICA supply as well (esp. if skull base or cavernous sinus extension) * May have supply from contralateral ECA branches * Embolization before resection * Biopsy has high risk of massive hemorrhage, may not be necessary (particularly avoid in outpatient setting) * Recurrence if incompletely resected

Answer 28

Pleomorphic Adenoma (Benign Mixed Tumor) * Most common (70%–80%) benign salivary neoplasm. * Unifocal mass, slow-growing, well demarcated. * Radiographic Features * Well-circumscribed, encapsulated mass * Lobulated or “bosselated” contour * Superficial posterior glandular location, 80% * Lesions are hypoechoic by US * Moderate enhancement on CT and MRI * Can enhance homogenously (typically smaller lesions) or heterogeneously with areas of cystic degeneration and necrosis * T1W MRI: * Low signal, larger lesions can be heterogeneous * May have areas of high signal if hemorrhagic * T2W MRI: * Intermediate to high signal, may be homogenous or heterogeneous (larger lesions) * May have peripheral low signal intensity capsule * **If very high signal (brighter than CSF): highly suggestive of pleomorphic adenoma** * **Calcification may be present, unusual in other parotid tumors****** * **Malignant transformation, 5%** * **Imaging characteristics that suggest malignancy include:** * **Irregular margins** * **Rapid growth** * **Low signal on T2W images** * **Adjacent soft tissue or bone invasion** * **Facial perineural spread** Case Report: The is a 24 x 21 x 38 mm multilobulated, well-circumscribed mass lesion within the left parotid tail, demonstrating heterogeneous signal and contrast enhancement. The medial margin of the lesion contacts the left mandibular angle, however, there is no extent into the deep lobe of parotid demonstrated. There is no abnormal mandibular marrow signal and no abnormal perineural enhancement involving the left facial or V3 nerves. The contralateral parotid gland appears unremarkable. Prominent cervical chain and submandibular lymph nodes demonstrated bilaterally, likely inflammatory. There is an encapsulated cystic lesion associated with an unerupted right maxillary tooth with T1 high signal content that demonstrates restricted diffusion - likely representing inspissated dentigerous cysts. No regions of high-grade cervical canal stenosis. No abnormal cervical marrow infiltration. Conclusion: The imaging morphology of the well-defined parotid lesion is in keeping with a pleomorphic adenoma involving the left parotid tail without the involvement of the deep lobe of parotid. The right parotid gland appears normal. An inspissated, likely dentigerous cyst is noted in the right maxillary sinus associated with an unerupted tooth. * Case courtesy of H&N spaces, Radiopaedia.org, rID: 28386' * May have areas of high signal if hemorrhagic * T2W MRI: * Intermediate to high signal, may be homogenous or heterogeneous (larger lesions) * May have peripheral low signal intensity capsule * If very high signal (brighter than CSF): highly suggestive of pleomorphic adenoma * Calcification may be present, unusual in other parotid tumors * Malignant transformation, 5% * Imaging characteristics that suggest malignancy include: Case courtesy of H&N spaces, Radiopaedia.org, rID: 28386

Answer 29

The extraadrenal neuroendocrine system comprises an integrated and complex system of dispersed tissue throughout the body that possesses unique regulatory functions. A single collection of this tissue is called a **paraganglion** (coined by Kohn in 1903), and the entire **chain of tissue constitutes the paraganglia** (,1). Paraganglia are frequently **located near nerves and vessels,** belying their special **chemoreceptor** function (,2). They arise from **neural crest progenitor cells** and are therefore of **neuroectodermal origin**. Paraganglia in the head and neck migrate along a **branchiomeric (of the branchial mesoderm) distribution.** Whereas those in the chest, abdomen, and pelvis follow the path of **parasympathetic nerve fibers along the perivertebral-periaortic axis.** Paragangliomas, the tumors of the paraganglia, arise from this specialized tissue at any site along these specific locations within the body. Accordingly, the distribution of these lesions is widespread. Within the head and neck, the four most common sites are the: 1. **carotid body** at the common carotid artery (CCA) bifurcation, 2. the **jugular foramen,** 3. along the **vagus nerve**, and 4. within the **middle ear**.

Answer 30

Scintigraphy: Technetium (Tc)-99m sestamibi washes out more rapidly from thyroid with retention in parathyroids Look for focal increased sestamibi uptake on early and delayed images. Case courtesy of Dr Abdallah Al Khateeb, Radiopaedia.org, rID: 43376

Answer 31

Cocaine Septum **A not-very-useful mnemonic for the causes of nasal septum perforation is:** **Say Water Coke Syrup Sugar Lemonade or say Nothing** **Mnemonic** * **S: sarcoidosis** * **W: Wegener granulomatosis (now known as granulomatosis with polyangiitis)** * **C: cocaine** * **S: syphilis** * **S: surgery** * **L: leprosy** * **N: non-Hodgkin T-cell lymphoma (NHL)** CT through the nasal passage and paranasal sinuses demonstrates a large anterior nasal septum perforation due to protracted cocaine use. A nasal septal perforation refers to a defect in nasal septum resulting in a communication between the two nasal cavities. It may affect either the bony, or cartilaginous septum. Most commonly it affects the anterior septal cartilaginous area although with syphilis it characteristically affects the bony septum. DDx * trauma * surgical * repeated cautery * digital trauma (nose picking) * malignant diseasemalignant tumours * non-Hodgkin lymphoma 5 * malignant granuloma * chronic inflammatory conditions * granulomatosis with polyangiitis 5 * syphilis * tuberculosis * sarcoidosis * poisons * industrial * chronic (\> 3 months) cocaine use 4 * topical corticosteroids * topical decongestants * idiopathic * Case courtesy of Assoc Prof Frank Gaillard, Radiopaedia.org, rID: 6833

Answer 32

Radiography * Widened prevertebral distance, rarely gas * In children: * must perform during inspiration and with neck extension; * if flexed, there may be pseudothickening of prevertebral soft tissues * Different measurements, rules for normal versus abnormal on radiography * See Fig. 7.30 * C2: ≤7 mm at any age * C6: ≤14 mm if \<15 years, ≤22 mm in adults CT appearance * Fluid/edema appear hypodense with enhancing wall * Thick enhancing wall suggests mature abscess * Stranding of fat * May have associated prevertebral muscles edema * Gas rarely present

Answer 33

Esthesioneuroblastoma * Intro * arises from olfactory epithelial cells * superior recess of the nasal cavity * commonly extends through cribriform plate * involve anterior and middle ethmoid air-cells on one side * extending through the cribriform plate into the anterior cranial fossa. * Contrast enhancement is often marked in both CT and MRI studies. * AKA * olfactory neuroblastoma * Other tests * MIBG would help distinguish from other differentials * Epidemiology * bimodal age distribution * one peak in (~2nd decade) * 5th to 6th decades. * There is no recognised gender predilection. * Clinical presentation * Clinical presentation is usually secondary to nasal stuffiness and rhinorrhoea or epistaxis. * Presentation is often delayed and symptoms may have been present for many months. * Patients often present late with larger tumours which can extend into the intracranial compartment (25-30% at diagnosis) and usually result in **anosmia** 2,3,7. * Pathology * Olfactory neuroblastomas are of **neural crest cell origin** 1. * Macroscopically, they are multilobulated pink-grey tumours. * Histology demonstrates variable differentiation, from well-formed neural tissue to undifferentiated neuroblasts with **pseudorosette** formation 2. * It has been suggested that olfactory neuroblastoma is actually part of the Ewing sarcoma group of tumours, rather than being related to neuroblastoma 5. * Radiographic features * The tumours are slow-growing and the choice of imaging will depend on the tumour's size. * **They begin as masses in the superior olfactory recess and initially involve the anterior and middle ethmoid air-cells unilaterally** * As they grow, they tend to destroy surrounding bone and can extend in any direction. * Often they are said to form a **"dumbbell-shaped"** mass with a **"waist**" as it passes through the **cribriform plate**. * This invasion may be superiorly into the anterior cranial fossa, laterally into the orbits and across the midline into the contralateral nasal cavity. They can also obstruct the ostia of paranasal sinuses, resulting in opacification of the sinus with secretions 2. * **cervical and retropharyngeal nodal metastases**, which are present in 10-44% of cases at diagnosis 6. * CT * CT is particularly useful in assessing bony destruction, although it cannot distinguish olfactory neuroblastomas from other tumours that arise in the same region 2. The mass is of soft tissue attenuation, with relatively homogeneous enhancement 3. Focal calcifications are occasionally present 3. * **These tumours are relatively slow-growing and thus, bony margins are often remodelled and resorbed**, rather than being aggressively destroyed 3. * MRI * Signal characteristics include: * T1: heterogeneous intermediate signal * T2: heterogeneous intermediate signal * T1 C+ (Gd): variable enhancement (usually moderate to intense) 3,7 * When an intracranial extension is present, peritumoural cysts between it and the overlying brain are often present. This may be helpful in distinguishing it from other entities (see below) 3,7. The margins of these cysts sometimes enhance 7. * Angiography/DSA * Angiography demonstrates a prominent tumour blush with arteriovenous shunting and persistent opacification. * **Nuclear medicine** * **As with other neuroblastomas, olfactory neuroblastomas are MIBG-avid. This potentially helps to differentiate them from other tumours that arise in region 1.** * Treatment and prognosis * Treatment usually involves combined chemotherapy and/or radiotherapy with surgical excision. Prognosis is significantly affected by the presence of distant metastases (see olfactory neuroblastoma staging). * no distant metastases: 60% 5-year survival 6 * distant metastases: 0% 5-year survival * Small localised tumours have a high cure rate, up to 85-90% 7. * Differential diagnosis * Unfortunately, imaging alone often struggles to distinguish between olfactory neuroblastomas and other aggressive malignancies in the region. The differential includes 1,2: * olfactory neuroepithelioma * rare and indistinguishable on imaging 4 * olfactory groove meningioma/haemangiopericytoma * especially if superior extension * sinonasal carcinoma (including SCC, minor salivary gland adenocarcinoma) * may appear identical * usually older patients * lack peritumoural cysts 3,7 * rhabdomyosarcoma * melanoma metastases * lymphoma * may appear identical * lack peritumoural cysts 3,7 * nasopharyngeal carcinoma * epicentre more posteriorly located * usually older patients * chordoma * epicentre more posteriorly located * high T2 signal * pituitary macroadenoma * epicentre more posteriorly located * juvenile nasopharyngeal angiofibroma * epicentre more posteroinferiorly located * almost exclusively in males * often somewhat younger Case courtesy of Assoc Prof Frank Gaillard, Radiopaedia.org, rID: 8861

Answer 34

the nasolacrimal duct

Answer 35

US findings: Well-defined **hypoechoic** mass May be hypervascular on Doppler There is a well-defined, homogeneous lesion posterior-inferior to the right lobe of the thyroid gland. It is hypoechoic in comparison to the thyroid gland. There is no calcification/ cystic space in it. The lesion elevates the echogenic posterior capsule of the thyroid gland. Few flow signals are present in the lesion. Case Discussion A female presented with generalised bone pain. Laboratory investigation showed an elevated serum parathyroid hormone. The ultrasound shows a well-defined, solid, vascular lesion posterior to the thyroid gland. The lesion is very likely to be a parathyroid adenoma in view of the clinical background. Surgical excision was done and histopathology confirmed the lesion being a parathyroid adenoma.

Answer 36

Rheumatoid larynx Involvement of the larynx in rheumatoid arthritis was first described by Sir Morell MacKenzie in 1880 (5). The incidence of rheumatoid arthritis of the larynx is higher in female (65%) than in male (20%) patients with rheumatoid arthritis (6). On laryngoscopy, the prevalence of rheumatoid arthritis of the larynx has varied between 32–75% (7–8). The prevalence varies between 54% and 72% on CT scans (7, 8). Although involvement of the larynx is frequent, only 26% of patients with rheumatoid arthritis have laryngeal symptoms; hoarseness and foreign body sensation are the most common symptoms (9). Other symptoms include dyspnea, odynophagia, coughing, sore throat, stridor, and acute airway obstruction causing inspiratory difficulties (6, 7, 10–12). Most patients with rheumatoid arthritis of the larynx have minor symptoms or are asymptomatic.

Answer 37

* search ectopic locations in the * parapharyngeal space including * carotid sheath, * retropharyngeal/retrooesophageal space, * thyrothymic ligament continuing into the anterior mediastinum, and * tracheoesophageal groove continuing into the * posterior mediastinum * 3% of superior parathyroid glands are retropharyngeal/retrooesophageal * 28% of inferior parathyroid glands are located along the thyrothymic ligament and anterior mediastinum * evaluate the thyroid gland for intrathyroid parathyroid glands or thyroid nodules, which may appear similar on CT although the latter are much more common

Answer 38

Sialoadenitis * Inflammation of the salivary glands. * can be acute or chronic * Acute Sialoadenitis * Bacterial and viral * (mumps most common viral infection) most common causes (parotid), * stones major predisposing factor for submandibular sialoadenitis * May be complicated by abscess * Chronic, Recurrent Sialoadenitis * Recurrent bacterial or nonbacterial infections * recurrent infection because of poor oral hygiene * Obstructive disorders of salivary glands * stone * tumor * Irradiation * autoimmune disease * idiopathic * Other conditions related to sialadenitis include: * Sjogren syndrom (2nd pricture) * chronic sialadenitis 2 * Mikulicz syndrome * chronic sialadenitis 2 * post-radiatio * post-irradiative sialadenitis 4 * iodine-131 administration 3 * HIV-associated sialadenitis or immune reconstitution inflammatory syndrome (IRIS), often presenting with bilateral parotid swelling 11. * Differential diagnos * sialadenosis * sarcoidosis * Sjogren syndrome * Case courtesy of Dr Mohammad Taghi Niknejad, Radiopaedia.org, rID: 20583 * Case courtesy of Dr Andrew Lawson, Radiopaedia.org, rID: 26270

Answer 39

Sjögren Syndrome * Case disccusion * Both parotid glands are enlarged with innumerable cystic lesions disseminated in both parotid glands, of low signal onT1, hight signal on T2, giving a honeycomb appearance. * On moderate heterogeneous enhancement is noted on postcontrast sequences. * Both submandibular glands show a similar but much less prominent involvement as compared to the parotid glands. * Ultrasound and MRI features are characteristic of Sjögren syndrome. * **Follow-up is mandatory i**n such case due to the high risk of developing a **malignant lymphoma** * Intro * Autoimmune disease causing inflammation of secretory glands (e.g., lacrimal, parotid, submandibular, tracheobronchial tree) * Types * Primary Sjögren syndrome * occurs in absence of other autoimmune disease * Secondary Sjögren syndrome * occurs in association with other autoimmune disease * rheumatoid arthritis [RA] * systemic sclerosis * primary biliary cirrhosis * Epid * Male-female ratio = 1 : 9 * (most common in menopausal women) * Clinical Findings * Sicca complex: * dry eyes and irritation (keratoconjunctivitis sicca), * dry mouth (xerostomia) * Salivary gland swelling * Radiographic Features (Neck) * Parotid gland enlargement (lymphoepithelial proliferation), imaging appearance depends on presence or absence of lymphocyte aggregates * **Intermediate stage**: numerous small cysts diffuse throughout parotids * **Late stage:** bilateral enlarged parotids, multiple cystic and solid intraparotid lesions * **Chronic stage:** diffuse atrophy and fatty replacement * May have punctate calcifications diffusely, with or without intraparotid cystic or solid nodules * Dominant parotid mass, progressive on imaging and/or clinical examination: may represent lymphomatous transformation * Sialography: alternating areas of ductal stenosis and dilatation (“string of beads”) * Markers * anti-Ro (SSA) antibody * anti-La (SSB) antibody * Case courtesy of Dr Ammar Haouimi, Radiopaedia.org, rID: 67792

Answer 40

* MESEC * Margin * Smooth 0 * ill-defined 0 * **lobulated/irregular 2** * **extrathyroidal extension 3** * Echogenicity * anechoic 0 * **hyper/iso 1** * **hypo 2** * **very hypo 3** * Shape * wider than tall 0 * **Taller than wide 3** * Echogenic foci * none 0 * large tail commet artifacts 0 * **Macro Calc 1** * **peripheral rim calc 2** * **Punctate echogenic foci 3** * Composition * cystic/almost completely cystic 0 * spongiform 0 * **mixed cystic/solid 1** * **solid/almost completely solid 2**

Answer 41

Clinical Findings * Osteoporosis * Gastrointestinal (GI) complaints * Renal calculi * Cardiovascular and other complications

Answer 42

* ethmoid bulla * infundibul

Answer 43

* The cause of Graves disease is unknown but is associated with: * human leukocyte antigen (HLA)-B8, * DR3 (white patients), and * HLA-Bw35, Bw46 (Asian patients). * Pathogenetically it is an autoimmune disease * T lymphocytes become sensitized to antigens within the thyroid gland * this stimulates B lymphocytes to synthesize antibodies: * thyroid-stimulating immunoglobulin (TSI). * These antibodies lead to stimulation of the thyroid-stimulating hormone (TSH) receptor, with resultant production and release of T3 and T4 * This leads to hyperthyroidism

Answer 44

Yes. Nodules with large cystic components are usually benign; **however, 20% of papillary cancers are cystic.** http://www.ajnr.org/content/31/10/1961 **C, Suspicious for malignancy in a 28-year-old woman. A longitudinal sonogram of a papillary thyroid carcinoma in the left lobe shows an eccentric configuration with an acute angle between the solid component and the wall (arrows), a microlobulation, and isoechogenicity. D, Malignant features in a 45-year-old woman. A longitudinal sonogram of a papillary thyroid carcinoma in the left lobe shows an eccentric configuration with an acute angle (arrows), macrolobulation, microcalcifications, and hypoechogenicity.**

Answer 45

* infraorbital ethnoid cell * ethmoid cell invading the medial floor of the orbit * bordering the infundibulum laterally

Answer 46

paradoxical middle turbinate

Answer 47

longus coli tendintis * prevertebral fluid secondary to Calcium hydroxyapatite deposition in the superior oblique fibres of the longus colli muscles. * Clinical * low grade fever * neck pain and stiffness * odynophagia * mild leukocytosis * Ddx for prevertebral fluid * retropharyngeal abscess * jugular vein thrombosis * thrombophelbitis

Answer 48

* Unilateral polypoid sinonasal lesion * consists of hyperplastic squamous epithelium * endophytic growth pattern * 10% co-exists with SCC * **Rad features** * Usually located along lateral nasal wall in region of the middle meatus +/- extension in the antrum * may have an **'emtrapped bone'** or internal calcifications * **focal hyperostosi**s of adjacent bone may indicate point of tumour attachemnt * A/w secondary sinsu inflammatory changes depending on exact site and extent of drainage pathway obstruction. * Variable internal enhancement * may be better seen on MRI * distinguishes from sinus polyps, secretions and inflammatory changes. * May have a **convoluted or cerebriform appearance** * **DDx** * antrochoanal polyp * sinonasal juvenile angiofibroma * myecetoma * mucocele * scc * Adenocarcinoma * Esthesioneuroblastoma

Answer 49

* paramedian position of the affected true vocal cord * widening of the ipsilateral laryngeal ventricle * sail sign * Expansion of the ipsilateral pyriform sinus * medial rotation and tickening of the aryepiglottic fold * Anteriormedial rotation of the arytenoid cartilage * cricoarytenoid muscle muscle atrophy A and B, Two consecutive axial CT scans in a patient with a right-sided glomus vagale show atrophy of the right PCA muscle and right cricothyroid muscle relative to the normal left side (arrowhead indicates normal left PCA muscle; arrow, normal left cricothyroid muscle)

Answer 50

* opacified expanded sinus * may occur in pneumatised anatomic variant air cells * smooth remodeling of sinus walls * low or intermediate (soft tissue) density on CT * MR signal * low T1 High T2 = water content * high t1 high t2 = high protein content * Dark T1, dark T2: very high protein/viscous content * no enhancement unless infected * mucopyocele * if there is an associated nodule of enhancementrr * considder tumour obstruction of sinus with secondary mucocele * COMPLICAIOTNS * breakthrough into orbit or anterior cranial fossa

Answer 51

SCC, 80% * Most in sinuses (70%), approximately 30% primarily in nasal cavity * Most commonly affected sinus is maxillary sinus 80% \> ethmoids 15% \> frontal, sphenoid * Imaging Characteristics * Solid, enhancing mass with irregular margins * Aggressive features, bone destruction * Decreased T2 signal in highly cellular tumors * CT good for bone detail but MRI typically superior for determination of overall extent, distinction from obstructive and inflammatory changes, perineural tumor spread, and intracranial extent * Specific histologic types may appear similar on imaging, require biopsy for definitive histopathology

Answer 52

* 60% of laryngeal SCC * Tumour arises from the true vocal cords * typically anterior vocal cord * anterior commisure * Change in voice or hoarseness is an early clinical finding * many are small at presentation (ie low T stage) * GLottis is vascular but with poor lymphatics * thus metastatic nodes uncommon * rarely can present clinically with abnormal central compartment * Delphian node * Evaluate extension to other parts of larynx or adjacent spaces, thyroid cartilage * extralyarungeal spread may occur anteriorly through criocothyroid ligament * Samll T1 tumours may be treated with laxer or XRT

Answer 53

* Subacute granulomatous * post viral in genetically predisposed pts * Thyroiditis (deQuervian) * HLA-B35 * fever chills * ESR raised * Thyrotoxic -\> eu -\> Hypo -\> recovery/pernament hypo * Subacute lymphocytic * autoimmune * painless * Post partum * Hashimotos * AI * early disease hyperthyroid 5%

Answer 54

Signs of Sialolithiasis * Evaluate for secondary signs: * Ductal dilatation * Inflammatory adenopathy (acute) * Acute gland inflammation (hyperenhancement, enlargement, adjacent stranding) * Chronically obstructed glands may be atrophic. * Mimick * Do not mistake calcification in the stylohyoid ligament for a calculus (follow the course of the duct). * Note that accessory parotid tissue can be affected by the same disease processes affecting the main gland, including calculi. * Complications of large stones: * Infection * Obstruction * Strictures * Gland atrophy

Answer 55

* Third Branchial Cleft Cyst * Rare * upper posterior cervical space or * low anterior neck * along anterior border of SCM

Answer 56

Rhinolith * **Differential diagnosis** * **paranasal osteoma** * **nasal tooth** * AKA * nasal calculi * Intro * uncommon lesions that result from a chronic inflammatory response to complete or partial mineralised encrustation of intranasal foreign bodies. * They are most commonly seen in children and cognitively impaired adults who insert foreign bodies into their nose. * Less frequently, trauma, surgery and dental work, nasal packing material, and plugs of ointment may also promote the development of a rhinolith. * Clinical presentation * Most rhinoliths ultimately produce clinical symptoms including unilateral purulent nasal dischargeand nasal obstruction. * There may be a marked lag between the initial insertion of the foreign body and the symptoms (as long as decades). * Radiographic features * Rhinoliths are usually unilateral and solitary, and most commonly between the inferior meatus and the nasal septum. * These lesions appear as a densely calcified mass in the nasal cavity, with displacement and expansion or destruction of the adjacent bony landmarks. * Some of the remote complications include perforation of the hard palate, bony destruction, erosion of the stone into the maxillary sinus, facial spasms, or septal perforation. * History and etymology * The first published report of a calcified foreign body in the nose appeared in 1654, in whichBartholini described a stone-hard foreign body that had grown around a cherry stone. The term rhinolith was first coined in 1845 to describe a partially or completely encrusted foreign body in the nose. * Case courtesy of Dr Sagar Shetty, Radiopaedia.org, rID: 49708

Answer 57

Second branchial cleft cyst The described CT features are of a right neck cystic lesion consistent with infected second branchial cleft cyst type II which is the most common type of this congenital anomaly. Classically, it is located at the anteromedial border of the sternocleidomastoid muscle, lateral to the carotid space, and at the posterior margin of the submandibular gland, related to the angle of the mandible. The location can be anywhere from the pharyngeal wall to the skin along the course of the second branchial apparatus.

Answer 58

Tumor Spread * Direct invasion * Maxillary sinus: * Posterior extension: infratemporal fossa/masticator space, PPF * Anterior extension: subcutaneous tissues of cheek * Inferior: maxillary alveolar ridge, buccal space, hard palate * Superior extension: orbit * Ethmoid or frontal sinus: intracranial extension, frontal lobe * LN metastases: retropharyngeal, level II, level IB * Perineural spread: * Varies based on exact location * PPF → multiple neural pathways, including spread to cavernous sinus via V2/foramen rotundum * Inferior orbital nerve → V2/foramen rotundum → cavernous sinus

Answer 59

* Hyperparathyroidism (HPT) * Usually detected by increased serum calcium during routine biochemical screening. * Incidence: 0.2% of the general population (female \> male). * Types * Primary HPT: * Adenoma, 80% * Hyperplasia, 20% * Parathyroid CA, rare * Secondary HPT: * Renal failure * Ectopic parathormone (PTH) production by hormonally active tumors * Tertiary HPT: * results from autonomous glandular function after long-standing renal failure

Answer 60

* rapidly progressive infection in immunocompromised pts involving bone and adjacent soft tissues VIA VASCULAR SPREAD * Risk factors * diabetes * prolonged Abx * Prolonged steroids * immunocomproimsed pt * Bone desdtruction and rapid extension into adjacent anatomic spaces * Infratemporal fossa * PPF * Orbit * intracranial * infiltration of adjacenet fat and soft tissues * Maxillary sinus: * preimaxillary fat infiltration * anterior * premaxillary * retorantral * Can be present without obvious bone destruction or subgtle focal areas of sinus wall erosion * findings may be subtle * infection spreads along vessles

Answer 61

* Partial laryngectomy * laryngofissure with cordectomoy * for early lesions limited to the VC * vertical hemilaryngectomy (1st picture) * removal of one true VC, laryngeal ventricle, false cord and thyroid lamina +/- vocal process of the arytenoid * Horizontal (supraglottic) hemilaryngectomy (2nd image) * almost all of the larynx above the ventricle is removed * spares the arytenoid cartilages * epiglottis, aryepiglottic folds, false vcs preepiglotic space, superior portiaon of the TC, +/- portion of the hyoid bone * near total layngectomy * removal of half of larynx, anterior part of the contralatreral true VC, hyoid, epiglottis, preepiglottic space, vallecular * Permanent tracheostomy needed for breathing * total laryngectoy * complete resection of larynx with reation of neopharynx * removal of entire larynx and preepiglotic space, hyoid bone, strap muscles, part of the thyroid gland * A neopharynx is created using muscular, mucosal and connective tissue layers and connects oropharynx to oesophagus * trachea no longer communicates with the pharynx. need tracheostomy to breath and prosthesis to speak

Answer 62

* anterior ethmoid complex * drains via the ethmoid bulla and hitus semilunaris * middle meatus *

Answer 63

* severe form of chronic sinusitis with polyposis as a result of immune response to fungal antigens * absence of tissue invasion * involves multiple sinuses * ethmoid\>maxillary\>frontal?shphenoid * Diffuse involvement distinguishing feature from some other forms of sinusisits * opacification and expansion of multiple sinues * inspissated centrally hyperdense and periphaly hypodense contents on CT * Can be very hypointense on T2 may mimic air!

Answer 64

* A mucocele is a true cystic lesion linded by sinus mucosa * occurs as a result of complete obstruction of a primary sinus ostium * inflammation * trauma * tumor * the bony walls of the sinus are remodeled as the pressure of secretions increases * in paediatric patients think * CF * immotile cillia syndrome * Location * frontaln 65% * ethmoidal * maxillary * risk factors * polyps

Answer 65

Laryngotracheal separation

Answer 66

Parotid Tumors * Benign, 80% * Pleomorphic adenoma * or benign mixed tumor * most common) * 70%– 80% * Warthin tumor * papillary cystadenoma lymphomatosum * Second most common benign parotid tumor * approx. 10% * Bilateral: 5%–20% * Male \> female * Rare * myoepithelioma, * oncocytoma, * basal cell adenoma * Malignant, 20% * Mucoepidermoid CA * 5% * CA arising from pleomorphic adenoma * 5% * ACC (cylindroma), * 2% * Adenocarcinoma, * 4% * SCC (extension from nearby skin or ear) * Lymphoma * metastatic lymphadenop

Answer 67

* Intro * Most common cause of proptosis in adults * A/w Graves disease * Bilateral and symmetrical enlargement of the EOM bellies. * IR \> MR \> SR * There is sparing of their tendinous insertions. * Clinical Presentation * Lid retraction * Proptosis, chemosis, corneal dryness, ulceration * Diplopia * Hypoglobus * Pathology * enlargement of the EOM and increase in the orbital fat volume * ABs to THS appear to cross-react with gas in the orbit leading to infiltration by activated T-lymphocytes and release of inflammatory mediators * Chronic cases -\> increased collagen deposition -\> fibrosis. * Involvement of the extraocular muscles in decreasing order of frequency: * levator palpebrae superiors muscle, then: * IM SLOw * IR * MR * SR * LR * Oblique muscles * The increase in orbital fat volume is a result of the venous congestion from the compression of the Superior ophthalmic vein and intrinsic adipose inflammation.

Head and Neck 4 Flashcards

(100 cards)