Rhinology Flashcards
How often does the alternating cyclic engorgement of nasal turbinates occur?
Every 2-4 hours
Increased obstruction when lying down or on dependent side with lateral recumbent position
What type of mucosa is in the paranasal sinuses?
Pseudostratified ciliated columnar epithelium
Limen nasi
Mucosal ridge between the nasal cavity proper and the nasal vestibule
Inborn disorders of mucociliary transport can occur because of what two defects?
- Ciliary dysfunction as in primary ciliary dyskinesia
- Increased viscosity of respiratory secretions as in cystic fibrosis
What can impair mucociliary transport?
Inflammation, infection, exposure to ciliotoxic agents
Describe the double layered mucus blanket
It consists of 2 layers: (1) an inner serous layer (ie, sol phase) in which cilia recover from their active beat and (2) an outer, more viscous layer (ie, gel phase), which is transported by the ciliary beat. Proper balance between the inner sol phase and outer gel phase is of critical importance for normal mucociliary clearance.
Ethmoturbinals
First - ascending portion is the agger nasi and the descending portion is the uncinate process
Second - middle turbinate
Third - superior turbinate
Fourth/Fifth- usually degenerate but can form supreme turbinate
Five anterior to posterior bony lamina encountered in endoscopic sinus surgery
- Uncinate process
- Ethmoid bulla
- Vertical portion of basal lamella of middle turbinate
- Vertical portion of lamella of superior turbinate
- Anterior wall of sphenoid sinus
Structures within the ostiomeatal complex
- Uncinate process: sickle shaped bone running anteriosuperior to posterioinferior with attachments along the lateral nasal wall. First structure encountered with MT medialized
- Ethmoid bulla
- Hiatus semilunaris; two dimensional slit that lies between the free edge of the uncinate process and the ethmoid bulla; connects the middle meauts into the infundibulum laterally
- Infundibulum: funnel shaped three dimensional space between the uncinate process medially and the lamina papyracea laterally
- Middle turbinate
- Maxillary sinus ostium
Variable sites of superior attachment of the unicinate process
- Laterally to lamina papyracea: most commonly resulting in a recessus terminalis; frontal recess drains medially to the uncinate and directly into the middle meatus
- Superiorly onto the skull base: frontal recess drains laterally into the infundibulum
- Medially to the middle turbinate: frontal recess drains laterally into the infundibulum
Parts of the middle turbinate
Anterior part: oriented in the sagittal place (vertical) and attaches to the agger nasi region anteriorly and the cribiform plate superiorly
Middle: oriented in the coronal plane obliquely and attached to the lamina papyracea
Posterior: oriented in the axial plane (horizontal) and attached to the lateral nasal wall at the lamina papyracea, maxilla and perpendicular process of the palatine bone.
The middle oblique part is the only part that can be sacrificed without compromising the integrity of the turbinate, Injury to the vertical or horizontal part will lateralize it and obstruct the middle meatus and posterior ethmoid complex
Where do the anterior and posterior ethmoid air cells drain into?
Anterior: middle meatus
Posterior: superior meatus
Describe the nasal fontanelles
Two areas along the lateral nasal wall where bone is absent. Anterior fontanelle is anterior to the uncinate bone and posterior fontanelle is posterior to uncinate
Describe where to find the sphenoid os
- Halfway to two thirds up the anterior wall of the sinus
- Medial to the posterior end of the superior turbinate in the majority of cases
- On average 7cm from the nasal spine at an angle of 30 degrees from the floor
Boundaries of the frontal recess
Medial: middle turbinate
Lateral: lamina papyracea
Anterior: posterior wall of agger nasi
Posterior: ethmoid bulla
Types of frontal cells
Type I: a single cell superior to the agger nasi
Type II: a tier of two or more cells above the agger nasi
Type III: a single cell extends from the agger nasi into the frontal sinus, above the floor of the frontal sinus but <50% of the frontal sinus height
Type IV: an isolated cell within the frontal sinus (Kuhn) or a single cell that extends into the fronal sinus for >50% of the frontal sinus height (Wormald)
All frontal cells lie anterior to the frontal recess
Supraorbital ethmoid cell
Cells posterior to the frontal sinus, pneumatizing superiorly to the orbital roof
Interfrontal sinus cell
Pneumatized intersinus septum and drains into frontal sinus, medially to the frontal osteum
Suprabullar cell
Cell superior to the ethmoid bulla
Frontal bulla cell
Cell superior to the ethmoid bull pneumatizing into the posterior frontal table (anterior skull base)
Suprabullar recess
Air cell space left between the ethmoid bulla and the fovea ethmoidalis when the bulla does not extend up to the fovea
Sinus lateralis/retrobulla recess
Air cell space found between the posterior surface of the ethmoid bulla and the vertical portion of the basal lamella
Sinus terminalis
Uncinate process terminates in the lamina papyracea; frontal recess drains medially to the uncinate process; this sinus is essentially a superior ending of the infundibulum
Keros classification of lateral lamella of cribiform height
Type I: cribiform plate 1-3mm below the fovea ethmoidalis
Type 2: cribiform plate 4-7mm below the fovea
Type 3: cribiform plate 8-16mm below the fovea (highest risk of skull base penetration)
Churg Strauss Syndrome
- Asthma, eosinophilia (>10%), allergic rhinosinusitis, pulmonary infiltrates, small to medium vessel vasculitis, mononeuritis multiplex or polyneuropathy
- P- ANCA antibodies often present
- Treat with oral steroids, cyclophosphamide and management of sinonasal symptoms
- Doesn’t usually present with epistaxis
- Clinical history follows 3 phases: 1) myalgias, arthralgias, malaise, fever, weight loss, asthma refractory to conventional tx 2) eosinophilia 3) vasculitis
Rhinoscleroma
- Infectious cause of rhinitis due to klebsiella resulting in a chronic granulomatous disease. Treat with ciprofloxacin or tetracycline.
- Histolopathology shows Mikulicz cells and Russel bodies
Rhinosporidiosis
- Painless, friable “strawberry” lesion caused by rhinosporidium seeberi from contaminated water (endemic in Africa and India)
- Histopathology shows pseudoepitheliomatous hyperplasia on histopathology
- Treat with excision, antifungals and dapsone
Rhinitis Sicca Anterior
- Dry, raw, nasal mucosa caused by changes in temperature/humidity, nose picking and dust
- Symptoms include dryness, crusting and epistaxis
- Treat with saline irrigation, topical antibiotics and oil based nasal ointments
What arteries supply Kisselbach’s plexus?
Anterior ethmoid, sphenopalatine, greater palatine, superior labial artery
Curacao criteria for HHT
- Epistaxis
- Mucosal telangectasias (oral or sinonasal)
- Visceral lesions (pulmonary arteriovenous malformation, cerebral AVM, hepatic AVM, spinal AVM)
- family history (first degree relative) ; disease is autosomal dominant
Definite diagnoses if 3; suspected if 2; unlikely if <2
Airflow through the nasal cavity
Middle meatus - 50%
Inferior meatus - 35%
Olfactory cleft - 15%
Types of olfactory disorders
- Transport or conductive (nasal inflammation, polyps, neoplasm, mass effect, septal deviation or nasal obstruction)
- Sensory (damage to neuroepithelium caused by drugs, neoplasms, radiation, toxic chemical exposure, viral URI)
- Neural olfactory loss (alcohol, tobacco, HIV, age, neurologic disorders like Parkinson’s, Kallman syndrome, Korsakoff psychosis, metabolic disorders like diabetes or malnutrition, trauma)
Causes of CSF rhinorrhea
- Traumatic (accidental or iatrogenic)
- Spontaneous ( may be related in increased intracranial pressure)
- Neoplasm
- Congenital
- Infection
Acute rhinosinusitis (ARS)
Any inflammation of the nose and sinus mucosa lasting 4 weeks or less with complete resolution
Recurrent ARS
Four or more annual episodes of rhinosinusitis without persistent symptoms in between
Chronic rhinosinusitis
Rhinosinusitis lasting longer than 12 weeks
Hallmark symptoms of acute rhinosinusitis
- Purulent rhinorrhea
- Nasal obstruction
- Facial pain and or pressure
Diagnosis of acute bacterial rhinosinusitis
Can be differentiated from viral sinusitis when hallmark symptoms persist without evidence of improvement for 10 days or symptoms worsen within 10 days after an initial period of improvement.
Treatment of acute bacterial rhinosinusitis
- Observation
- First line antibiotic: Augmentin
- If penicillin allergic then fluroquinolone (levofloxacin or moxifloxacin) or doxycycline
- Symptomatic treatment with nasal saline irrigation, nasal steroids and short term decongestants
Chandler classification of orbital complications during ARS
- Preseptal cellulitis
- Orbital cellulitis
- Subperiosteal abscess
- Orbital abscess
- Cavernous sinus thrombosis
Pathophysiologic contributors to chronic rhinosinusitis
- Predominance of T helper 2 cytokines
- Predominance of esoinophils
- Staphlococcal super antigen
- Deficiency in innate immunity
- Impaired mucociliary clearance
- Alterations in microbiome
Symptoms of CRS
- Nasal obstruction/congestion
- Hyposmia/anosmia
- Nasal discharge/postnasal drip
- Facial pressure
- Cough
- Wheeze (asthma)
Diagnosis of rhinosinusitis - major and minor symptoms
Diagnosis requires two major or one major and two minor symptoms
Major symptoms: facial pain/pressure; facial congestion/fullness; nasal obstruction/blockage; nasal discharge/purulence; hyposmia/anosmia; purulence on nasal exam; fever (acute rhinosinusitis only)
Minor symptoms: headache, fever (non acute), halitosis, fatigue, dental pain, cough, ear pain/pressure/fullness
Bent Kuhn criteria for allergic fungal sinusitis
Major criteria: type 1 hypersensitivity, nasal polyposis, characteristic CT findings (expansion of sinuses, asymmetry, heterogenously dense material in sinuses), positive fungal smear, eosinophilic mucin without tissue invasion
Minor criteria: asthma, unilateral predominance, serum eosinophilia, radiographic bone erosion, fungal culture, Charcot-Leyden crystals
Aspirin exacerbated respiratory disease
- Presence of polyps, asthma and asthma exacerbated by Cox-1 inhibitors (aspirin and NSAIDS)
- Caused by abnormality of arachidonic acid cascade that leads to increased production of proinflammatory leukotrienes
- Cox-1 inhibitors lead to increased production of leukotrienes, leading to severe worsening of asthma symptoms and or allergy like symptoms
Pathophysiology of Cystic Fibrosis
- Autosomal recessive defect in chloride ion channel
- Multiple different mutation in CF conductance transmembrane conductance regulator (CFTR)
- F508 deletion is most common
Granulomatosis with Polyangiitis
- Small medium vessel vasculitis
- C ANCA antibodies often present
- Can present with severe chronic inflammation, granulation tissue, chronic mucosal crusting, septal perforation and erosion of sinonasal structures, saddle nose deformity
Sarcoidosis
- Noncaseating granulomatous disease
- Systemic manifestations: bihilary lymphadenopathy on chest xray, fatigue, night seats, weight loss, erythema nodosum, uveiitis, peripheral lymphadenopathy, Heerford syndrome (facial nerve palsy, uveitis, fever, enlarged parotid glands)
- Sinus symptoms: polyps, chornic inflammation, mucosal nodules or cobblestoning of mucosa, mucosal crusting
Three phases of Churg Strauss
- Prodromal - asthma and upper respiratory involvement
- Peripheral eosinophilia (pulmonary or GI involvement)
- Disseminated/vasculitic phase (lung, CNS, kidney, GI, skin)
Ddx of Benign Sinonasal Neoplasms
- Osteoma
- Fibrous dysplasia
- Ossifying fibroma
- Chordoma
- Cementoma
- Hemangioma
- Inverted papilloma
- JNA
- Pleomorphic adenoma
- Schwannoma
- Neurofibroma
Ddx of Malignant Sinonasal Neoplasms
- Esthesioneuroblastoma
- Lymphoma
- Ewing sarcoma
- Chondrosarcoma
- Rhabdomyosarcoma
- Nasopharyngeal carcinoma
- Small cell carcinoma
- Squamous cell carcinoma
- Sinonasal undifferentiated carcinoma (SNUC)
- Adenocarcinoma
- Adenocystic carcinoma
- Mucoepidermoid carcinoma
- Hemangiopericytoma (both benign and malignant types)
- Peripheral nerve sheath tumor
Ddx of Congenital Sinonasal Neoplasms
- Dermoid
- Teratoma
- Glioma
- Encephalocele
Ddx of Inflammatory Sinonasal Neoplasms
- Polyp
- Antrochoanal polyp
- Inverting papilloma
Ddx for Sinonasal “Blue Cell” Tumors
- Rhabdomyosarcoma
- Esthesioneuroblastoma
- Lymphoma
- Melanoma
- SNUC
- Hemangiopericytoma
- Immature teratoma
- Carcinoid
- Peripheral nerve sheath tumor
Radkowski staging for JNA
Stage IA: limited to nose or nasopharynx
Stage IB: extension into at least one paranasal sinus
Stage IIA: Minimal extension through sphenopalatine formaen, includes minimal part of medial pterygomaxillary fossa
Stage IIB: full occupation of pterygomaxillary fossa with bowing of posterior wall of maxillary sinus on CT (Holman-Miller sign); lateral or anterior displacement of maxillary artery branches; may have superior extension with orbital bone erosion
Stage IIC: extension through pterygomaxillary fossa into cheek, temporal fossa or posterior to pterygoids
Stage IIIA: skull base erosion with minimal intracranial extension
Stage IIIB: skull base erosion with extensive intracranial +/- cavernous sinus
Krouse staging system for Inverted Papilloma
T1 - limited to one area of nasal cavity
T2 - involvement of medial wall of maxillary or ethmoid sinuses and or the osteomeatal complex
T3- involvement of superior, inferior, posterior, anterior or lateral walls of maxillary sinus
T4- Tumors with extrasinonasal spread or malignancy
Kadish staging of Esthesioneuroblastoma
Stage A: tumor limited to nasal cavity
Stage B: extension to paranasal sinuses
Stage C: extension beyond nasal cavity/sinuses
Stage D: cervical nodes or metastatic disease
Frontal Sinus Draf procedures
Draf I: Complete ethmoidectomy with removal of bulla and suprabullar cells
Draf IIa: enlargement of frontal sinus outflow tract with removal of all occupying cells (frontal sinusotomy)
Draf IIb (unilateral frontal sinus drill out): removal of floor of frontal sinus from lamina papyracea to the septum, to produce the largest possible unilateral outflow tract
Draf III (modified Lothrup): complete drill out of floor of the frontal sinus, frontal beak and intersinus septum and adjacent part of nasal septum
What cells contribute to formation of the nose during 4th week of embryogenesis?
Neural crest cells
Before closure during embryogenesis what are the following spaces called?
Between frontal and nasal bones
Between frontal and ethmoid bones
Between nasal bones and nasal capsule
Fronticulus nasofrontalis, foramen cecum, prenasal space
Into what structures do the medial and lateral processes of the nasal pits and the maxillary process of the maxilla develop?
Medial nasal pit: nasal septum, philtrum, premaxilla
Lateral nasal pit: Nasal alae
Maxillary process: lateral nasal side wall
What embryologic membrane separates the nasal and oral cavities and normally degenerates to allow open passages as the choanae are formed by deepening olfactory pits?
Nasobuccal membrane
Nasal bones attach to what structures in the facial skeleton
Frontal bone, nasal process of maxilla, upper lateral cartilages, contralateral nasal bone, perpendicular plate of ethmoid, cartilagenous septum
What structure does the frontal process of the maxilla, nasal floor and lateral fibrofatty tissue form?
Piriform aperture
Boundaries of external nasal valve
Caudal septum, lower lateral cartilages (caudal edge of lateral crus junction with upper lateral cartilage), piriform aperture
Components of nasal septum
Perpendicular plate of ethmoid bone, quadrangular cartilage, vomer, maxillary crest, palatine bone
Blood supply of nasal septum
- Anterior and posterior ethmoid arteries (superior septum)
- Sphenopalatine artery branches/posterior septal branch (posterior/inferior septum)
- Greater palatine artery (posteriorly)
- Superior labial artery (anteriorly)
The uncinate process is an extension of what bone
Ethmoid
What is the opening to the space between the uncinate and the ethmoid bulla?
Semilunar hiatus
The uncinate process covers the medial aspect of which space that provides a common drainage pathway for some of the anterior sinuses?
Infundibulum
Attachment sites of uncinate
Ethmoid crest of maxilla, lacrimal bone, ethmoidal process of inferior turbinate bone, palatine bone via the lamina perpendicularis
The lamina paprycea is formed by which bone
Ethmoid
Nasolacrimal duct empties under which structure?
Inferior turbinate (via Hasner valve)
What structure separates the anterior and posterior ethmoid sinuses?
Basal lamella
What is the horizontal plate of the ethmoid bone that forms the roof of the ethmoid sinus and separates the ethmoid air cells form the anterior cranial fossa?
Fovea ethmoidalis
What are the three infundibular cells that are anterior ethmoid air cells?
Agger nasi, Terminal cell (recessus terminalis), suprainfundibular cell
Which cell is the most anterior of the ethmoid cells and forms near the attachment of the middle turbinate to the lateral nasal wall?
Agger nasi
What arterial structure usually runs through the roof of the ethmoid bulla?
Anterior ethmoid artery
An infraorbital ethmoid cell that pneumatizes into the maxillary sinus and can narrow the maxillary sinus ostium
Haller cell
Where do the posterior ethmoidal cells drain
Superior meatus
Air cells that pneumatize lateral or posterior to the anterior wall of the sphenoid sinus
Onodi cells
First sinus to develop embryologically?
Maxillary
Where is the most common location for the maxillary ostium within the infundibulum?
Inferior third (65%)
What structure runs through the roof of the maxillary sinus?
Infraorbital nerve
A series of three or four frontal furrows arise out of the ventral middle meatus and give rise to what?
First frontal furrow = agger nasi
Second frontal furrow = frontal sinus
Third/fourth frontal furrow = anterior ethmoid cells
What is the last sinus to fully develop and at what age has it typically reached full size?
Frontal sinus, late teens
The spread of frontal sinus infections intracranially is commonly thought to pass through what structures?
Foramina of Breschet (small venules that drain the frontal sinus mucosa to the dural veins)
When is sphenoid sinus finish developing
Around age 9-12
Surgical landmarks to identify sphenoid sinus
- 6.2-8.0cm from anterior nasal spine
- 30-40 degrees from nasal floor
- Medial to posterior end of superior turbinate
- Halway up anterior sphenoid wall
In what % of patients is carotid artery dehiscent in sphenoid sinus?
~15%
What nerve is most medial in cavernous sinus?
VI
- This explains why abducens palys may be preferentially affected in sphenoid disease
The intersinus septum of the sphenoid sinus can be attached to what critical structure?
Internal carotid artery
What is the space between the internal carotid artery and the optic nerve within the sphenoid sinus called?
Opticocarotid recess
What neurovascular structures are set within the parasellar cavernous sinus?
- Internal carotid artery
- Cranial nerves III, IV, VI, V1, V2
What structures pass through the optic canal?
Optic nerve, ophthalmic artery and vein
The vidian nerve is formed by whcih two nerves before it runs through the vidian canal and exits into the pterygopalatine fossa?
- Greater superficial petrosal nerve from the geniculate ganglion of facial nerve (parasympathetic fibers from superior salivary nucleus)
- Deep petrosal nerve from the sympathetic plexus of internal carotid artery
Sternberg canal
Lateral craniopharyngeal canal that may persist in the adult patient and lead to encephalocele formation and CSF leak and most commonly is noted in patients with significant lateral pneumatization of sphenoid sinus.
What major branches of internal maxillary artery provide artery blood supply to the nose?
- Sphenopalatine artery
- Descending palatine artery -> greater and lesser palatine arteries
The sphenopalatine foramen is located posterior to attachment of middle turbinate to lateral nasal wall, may have several foramina and almost always is demarcated by what small, raised bony crest just anterior or anteroinferior to the foramen?
Crista ethmoidalis of palatine bone
The SPA can exit the foramen in up to 10 separate branches. What are the most common branches and their distribution?
- Lateral nasal artery: lateral nasal wall including turbinates
- Posterior septal artery: posterior/inferior septum
When ligating the anterior ethmoid artery via an external approach, the vessel can be found running in what suture line?
Frontoethmoid suture
What is the distance between the anterior lacrimal crest of the maxilla’s frontal process to the anterior ethmoidal artery
20-25mm
What is the average distance between the anterior and posterior ethmoidal arteries?
10-19mm
What is the average distance from posterior ethmoid artery to optic nerve?
3-7mm
What intranasal vessels are branches of the internal carotid artery?
Anterior and posterior ethmoid arteries
Woodruff plexus
Arterial plexus formed along posterior lateral nasal wall just under the inferior turbinate by branches from the ascending pharyngeal, posterior ethmoid, SPA and lateral nasal arteries.
True or false the venules within the respiratory mucosa of the nasal and paranasal cavities do not have valves.
true
Where do the sphenopalatine (1), ethmoid (2), angular (3), and anterior facial veins (4) drain?
1 - pterygoid plexus
2- superior ophthalmic vein
3 - opthalmic vein -> cavernous sinus
4 - common facial vein -> internal jugular
Primary blood supply to external nose
Angular artery (facial artery) Superior labial artery (facial artery)
What major nerve branches arise from nasociliary nerve (V1) and what regions of the nose do they supply?
- Infratrochlear nerve -> medial eyelid skin
- Anterior ethmoid nerve -> anterior/superior nasal cavity, lateral nasal wall, and septum, external skin of nasal tip
What runs in foramen rotundum
V2
After exiting the foramen rotundum V2 contributes fibers to the pterygopalatine (sphenopalatine) ganglion, which then supplies innervation to the nose via which branches?
- Infraorbital nerve -> anterior area of inferior meatus, anterior nasal floor, nasal vestibule
- Superior nasal branches -> posterior superior/middle turbinates, posterior ethmoid sinuses, face of sphenoid, nasal vault, posterior septum
- Nasopalatine nerve -> anterior hard palate
- Greater palatine nerve -> middle/inferior meatus, posterior aspect of inferior turbinate
Where do the parasympathetic fibers that provide vasodilation and secretomotor stimulation to nasal mucus glands synapse?
Pterygopalatine (sphenopalatine) ganglion
Superior salivatory nucleus -> nervus intermedius -> geniculate ganglion -> vidian nerve -> pterygopalatine ganglion -> sphenopalatine nerve branches -> vasodilation/secretomotor function
Postganglionic sympathetic fibers that ultimately control vasoconstriction in the nose arise from what ganglion?
Superior cervical ganglion
T1-T3 -> superior cervical ganglion -> internal carotid artery plexus -> join greater superficial petrosal nerve -> vidian nerve -> pterygopalatine ganglion -> sphenopalatine nerve branches -> vasoconstriction
Where do olfactory neruons synapse?
Olfactory bulb
Bones of the orbit
lacrimal, ethmoid, frontal, maxillary, sphenoid, zygomatic, palatine
What extraocular muscle is at highest risk during medial orbital decompression for Graves opthalmopathy?
medial rectus
What epithelium covers the cribiform plate bilaterally, extending to the superior and middle turbinates?
Olfacotry neuroepithelium: pseudostratified columnar epithelium
What part of the nasal cavity is composed of stratified keratinizing squamous epithelium, hair follicles, sebaceous glands and sweat glands?
Nasal vestibule
What is another name for the ciliated pseudostratified columnar epithelium that lines the nasal and paranasal cavities?
Schneiderian membrane (ectodermally derived)