耳鼻喉科Otolaryngology topic fourteen: Larynx & pharynx

Larynx & pharynx

1. Anatomy

Larynx

-- laryngeal cartilage: x 9

-- cricoid cartilage: the only cartilage 360° surrounding the trachea 

-- arytenoid: 4 intrinsic laryngeal muscles attached

Pharynx

-- narrowest at cricopharyngeal m. (upper esophageal sphincter)

2. Microstructure for phonation

-- cover: epithelium

-- transition: lamina propria

-- body: thyroiarytenoid

--> mucosa wave

3. Innervation

-- superior laryngeal n. external branch: CT muscle

-- recurrent laryngeal n. : all the other intrinsic muscles

4. Swallowing: 5 steps

-- soft palate closure

-- larynx elevation/ anterior movement

-- epiglottis 

-- constrictor muscle

-- crycopharyngeal m. relaxation

*** Right side bronchus: more straight, beware of choking with foreign body

5. Congenital abnormalies

-- laryngomalacia: cartilage/soft tissue collapsing inward during inhalation 

-- vocal cord paralysis: children--> bilateral, combined with other CNS defects 

6. Acquired diseases

-- acute laryngitis: virus infection

-- acute epiglottitis: Hemophilus influenza, airway obstruction, 2~6 y/o children/immunocompromised

-- laryngopharyngeal reflux(LPR): foreign body sensation, granuloma(LPR induced), need 24 hr pH monitor

-- Reinke's edema(polypoid vocal cord): @superficial lamina propria, smokers

-- laryngotracheal trauma: external, iatrogenic(bilateral)

-- laryngotracheal stenosis

-- foreign body ingestion (2/3)/aspiration(1/3):@ cricopharygeal m., 2~4 y/o

               --> pins

               --> peas

               --> coins

               --> meat, bones 

7. Head and neck cancers

-- male >> female : most obvious difference in esophageal cancer

-- 10~20% distal metastasis, mostly to lungs

-- treatment: anterior parts, ex: oral cavity--> surgery; naso/oropharynx: CCRT

 

耳鼻喉科Otolaryngology topic thirteen: Maxillofacial injury

Maxillofacial injury

1. Types and presentations

-- sport injury: from frontal bone to mandible  ↓

-- traffic injury:  from the lower part of a head to the upper  ↑

2. Top priority: airway

Beware of

-- fallen teeth

-- tongue

-- blood clot

3. Circulation

-- rarely cause shock

4. Secondary survey

-- medical record, drug history, allergy, CBC, CXR, urine routine...

5. Intervention

-- surgery: 5~8 days afterwards

-- suture: DO NOT create dead space

-- DO NOT offer morphine as they depress cough reflex and constrict pupils

-- Avoid treatment if no significant displacement of zygoma is present.

-- intervention when orbital floor damage>50%

-- can use iliac crest for reconstruction

6. Trauma

-- 70% lower extremity 

-- 50% ↑upper extremity, chest

7. PE/CT check key spots

-- eminence(-) --> check zygoma 

-- vertical buttress

-- mandible 

-- orbit 

-- soft tissue if complex injury ( eyes, facial n., dental occlusion...)

***Forced duction test: check orbit floor fracture

***Medial canthal ligament

8. Le Fort classification of maxilla fracture

From: RosarioVanTulpe
Red: type 1
Blue: type 2
Green: type 3, craniofacial

-- type 1: floating palate

-- type 2: infraorbital nerve, 35~55% (highest!)

-- type 3: worst-->raccoon eyes, panda face, CNS leakage, olfactory n. damage; least common

9. Zygoma fracture

-- lateral canthal ligament: causing diplopia 

10. Sinus fracture & CSF rhinorrhea

-- caution: anterior cranial fossa, cribriform plate, ethmoid sinus (maxillary sinus-->less likely)

-- 25% CSF leakage

-- CSF rhinorrhea after 1 wk, unilateral, wet handkerchief test, beta-2 transformin

-- treatment: absolute bed rest 7~10 days, avoid weight-lifting, acetazolamide, surgery

*** Antibiotics are NOT needed.

-- localization of CSF rhinorrhea: lumber puncture + contrast media/radioactive agents

11. Children

-- anatomy: cranium to face ratio↑

-- earlier treatment

耳鼻喉科Otolaryngology topic twelve: Outer and middle ear diseases

Outer and middle ear diseases

1. Auricle

Blood supply (external carotid a.)

-- occipital a.

-- posterior auricular a. 

-- superficial temporal a. 

Nerve

-- CN5 

-- CN7, 9, 10

-- greater auricular n.

2. External auditory canal

-- external 1/3: cartilage, sebaceous gland, follicle, ceruminous gland

-- internal 2/3: more fragile

-- junction: isthmus, narrowest

3. Auricle diseases

Preauricular sinus

-- Brachial arches fail to fuse.

-- can be bilateral or unilateral

-- treatment: total resection, but  recurrence↑

Microtia

-- male

-- unilateral atresia, right side

-- grade 2: lower part normal; grade 4: combined with other brachial arch problems

-- treatment: early amplification by hearing aid if bilateral (bone transmission)

Perichondritis/chondritis

-- DM, trauma, post-OP

Relapsing polychonditis

-- autoimmune related, idiopathic

-- All cartilages may be affected.

-- earlobe unaffected
-- treatment: steroid

Herpes zoster oticus

-- VZV

-- pain, vesicles after 3~7 days

-- Ramsay-Hunt syndrome: CN7--> facial palsy, open eyes; CN8--> tinnitus, headache, hearing loss; CN9,10

-- treatment: acyclovir/valcyclovir, steroid, ZnO, corneal protection

Malignancy

-- squamous

-- basal cell

-- melanoma

4. External ear canal diseases

Cerumen impaction and foreign body 

Acute otitis externa (swimmer's ear)

-- pain while pulling/pressing auricle

-- microbiology: Pseudomonas, S. aureus (second infection)

-- treatment: topical antibiotics except DM/ immunosupression

Otomycosis

-- NOT related to immune status

-- microbiology: Apergillus, Candida

Necrotizing external otitis

-- extremely painful, seeing granuloma, invading peripheral soft tissues (even skull base!)

-- microbiology: Pseudomonas, MRSA

-- progress quickly

-- exam. tools: Tc99m/CT for bones, Gallium scan for F/U, MRI

-- treatment: antibiotics, surgery

5. Reflexes of the middle ear/ nerve passing
-- CN5-->tensor tympani at neck of malleus-->tighten eardrum
-- CN7--> stapedius m.-->pulling away stapes-->acoustic reflex
-- chorda tympani n.(taste of anterior 2/3 of tongue)->between malleus and incus

6. Middle ear diseases


Eardrum(=tympanic membrane) perforation
-- traumatic: wedge shape
-- central perforation: less likely to develop into cholesteatoma
-- Otic drops: choose quinolones among antibiotics

Atelectatic and adhesive otitis media
-- middle ear negative pressure-->erosion of ossicles

Cholesteatoma
-- epithelium in abnormal middle ear region-->erosion of ossicles
-- congenital or acquired
-- DDx: chronic myringitis, atrophic scar(lacking fibrous tissue)

Acute otitis media

-- children, after URI

-- acute: <3 wks

-- diagnosis triad: acute, middle ear effusion(pus), symptoms

-- cannot rule out polyp, cyst, tumor
-- microbiology: Streptococcus pneumonia, Hemophilus influenza, Moraxella catarrhalis, RSV, inflenza, parainflenza, rhinovirus
-- treatment: amoxicillin, augmentin

Chronic otitis media
-- chronic: >3 months
-- structural change
-- microbiology: Pseudomonas aeruginosa, Staphylococcus aureus, anaerobics

Otitis media with effusion (OME)
-- NO pus, asymtomatic, plugged sensation
-- 6 months~4 y/o , recover in 3 months automatically 
-- chronic if bil. >3 months, uni. > 6 months; recurrent if >4 times in a year, >3 times in 6 months
-- diagnosis tool: pneumatic otoscope
-- DO NOT perform adenoidectomy if first episode
-- DDx: NPC if unilateral in adults

Otosclerosis
-- female > male, whites
-- osseous dyscrasia limited to the temporal bone (affecting otic capsule)
-- 70% bilateral, progressive hearing loss
-- Schwartze’s sign

Temporal bone trauma
-- 30%~75% head injuries, related to motor vehicle accidents
-- longitudinal: 70~90%  
-- transverse: 50% facial nerve injury, more likely to cause hearing loss
-- may lead to BPPV, perilymph fistula

7. Middle ear surgery

Tympanoplasty (Wullstein, 1953)
-- type 1:  connect to malleus
-- type 2:  connect to incus
-- type 3:  classic-->connect to stapes; modified-->place bone strut, stapes(+)
-- type 4:  classic-->connect to foot plate of stapes; modified-->place TORP, stapes(-)
-- type 5a: footplate(-)
-- type 5b: footplate(-), horizontal semicircular canal
-- modified type 3 & modified type 4--> ossiculoplasty, made from Polycel, titanium

耳鼻喉科Otolaryngology topic eleven: Otoneurology & vestibular system

Otoneurology & vestibular system

1. Central pathways

-- vestibulo-ocular reflex (VOR) : CN3,4,6

-- vestibulo-spinal reflex (VSR): lateral tract for extremities, medial tract for central muscles

-- vestibulo-vegetative reflex (VVR) : GI related

2. Dizziness and DDx

Duration is the key!

-- seconds: benign paroxysmal positional vertigo, superior semicircular canal dehiscence(SSCD, induced by noise, DDx by CT), perilymphatic fistula 
-- minutes: vertebrobasilar insufficiency ; migraine-related vertigo

-- hours: meniere’s disease
-- days: vestibular neuritis, labyrinthitis

3. Nystagmus
-- slow phase: speed, pathologic direction
-- fast phase: descriptive direction
-- transverse: inner ear problems
-- vertical: CNS problem
-- spontaneous
-- gaze (Brun's nystagmus: ─, cerebellopontine; down-beat nystagmus: ↓, Arnold-Chiari malformation = narrow foramen magnum)
             > uni-directional: inner ear, 
             > multi-directional: brain, variable intensity
-- normal ones: optokinetic nystagmus, caloric-test induced(COWS)

*** Closing the eyes, darkness, Frenzel glass, ENG would help the observation of nystagmus.

4. Coordination tests

Equilibratory
-- Romberg: eye close-->proprioception
-- Romberg on foam: eye close--> vestibule
-- tandem Romberg: similar to Romberg on foam

Non-equilibratory (cerebellum function)
-- circle drawing: dyssynergia
-- some for dysmetria
-- some for dysdiadochokinesia
-- smooth persuit
-- saccades

5. ENG and caloric test
(│right side wave angles-left side wave angels│/ sum of both-side wave angles ) x 100%
normal: <20. the side with smaller angle-->weaker function

6. Other tests
-- cervical vestibular myogenic potential
-- ocular vestibular myogenic potential
-- posturography
-- rotational chair test

耳鼻喉科Otolaryngology topic ten: Speech and voice

Speech and voice

1. Anatomy

-- ventricular folds

-- ventricle

-- true vocal folds

2. Histology

Three layers forming vocal fold

-- epithelium

-- lamina propria

    -->superficial layer = Reinke's space: loose, containing fluid, between mucosa and vocal ligament, determining timbre

    -->intermediate layer

    -->deep layer

-- muscle layer (posterior cricoarytenoid muscle--> abduction; stimulated by recurrent laryngeal nerve)

3. Sound production

-- vibrating frequency: men-->100, women-->200 per second
-- superior laryngeal nerve, recurrent laryngeal nerve

4. Tools for examination/ evaluation

-- laryngeal mirror

-- laryngeal telescope: not elastic, clearer than fiberscope

-- nasopharyngo-laryngo-fiberscope: more elastic, inserted from nose

-- videolaryngo-strobo-scopy: use flash light to record vocal cord movement

-- perceptual evaluation of sound: 0--> best; 3--> worst

-- aerodynamic test- maximum phonation time(MPT): normally >10 secs

-- aerodynamic test- mean flow rate(MFR): MPT↓-->MFR↑

-- acoustic analysis- fundamental frequency

-- acoustic analysis-perturbation measures(jitter: frequency change, % ; shimmer: loudness change, dB)

-- phonetogram(vocal profile): Falsetto with less contact surface, vocal fry with more contact surface 

-- laryngeal electromyography

5. Functional voice disorders

Muscular tension dysphonia

-- overuse of vocal cords

-- hyperfunctional 

Chronic chorditis

-- overuse of vocal cords, heavy smokers

Vocal nodules

-- overuse of vocal cords, wrong speaking habit

-- bilateral, hourglass shape vocal cords

-- DDx: polyp

Vocal polyp

-- phonotrauma 

-- unilateral, bleeding 

Cordal cyst

-- hard to distinguish from polyp, may need patho proof

-- less effect on sound comparing to polyp

Contact ulcer (granuloma)

-- post trachea tube insertion

-- posterior 1/3

Ventricular dysphonia 

-- using ventricular fold when speaking

Conversion (hysterical) dysphonia

-- long term or sudden onset emotional stress

-- recover when the patient cannot hear himself/herself

Mutational falsetto

-- resist voice change during puberty

6. Organic voice disorders

-- senile atrophy, androphonia, hypothyroidism

-- inflammation: Reinke's edema(heavy smokers), infection, irritant exposure, granuloma

-- congenital: sulcus vocalis, glottic web

-- neuromuscular: paralysis(unilateral), spasmodic(treat with botulism) 

-- neoplastic: need to DDx via scope and patho, leukoplakia, papilloma, carcinoma

-- vascular

7. Articulate disorders

-- mental

-- CNS

-- hearing

-- functional, structural

耳鼻喉科Otolaryngology topic nine: Audiology

Audiology

1. Treatment plan:
-- sensory↓: surgical  treatment
-- conduction↓: medical treatment

2. Cochlear
-- scala vestibuli, scala media(Organ of Corti), scala tympani
-- apex-->low pitch; base-->high pitch

3. Audiogram (test average hearing threshold)
-- frequency: 500, 1000, 2000, 4000 Hz
-- amplitude: start from loud sounds
-- unit: dB SPL or dB HL over Hz
-- new machine in Taiwan:  S1-S10, from good to bad function, start from the level of S5

4. Hearing aids
-- BTE
-- ITE
-- ITC
-- CIC

5. Tuning fork tests
-- 512 Hz
-- Weber test: midline, test sound transmission through bones
-- Rinne test: compare air conduction and bone conduction

6. Tympanogram: external ear canal pressure change--> check tympanic membrane's movement

7. Acoustic reflex
-- CN8--bilateral superior olive-->CN7-->stapes m.

8. Auditory brainstem response (ABR)
-- can test threshold and delay(schwannoma)

9. Otoacoustic emission (OAE)

10. Speech reception threshold (SRE)

11.  Conductive hearing loss
-- air-bone gap > 60dB

耳鼻喉科Otolaryngology topic eight: Inner ear diseases

Inner ear diseases

1. Neurologic pathway:

-- spiral ganglion--> cochlear nucleus-->bilateral superior olive (pons) -->inferior colliculus (midbrain) -->medial geniculate body (thalamus) -->auditory cortex

2. Detect rotation

-- angular: semicircular canal--> crista angularis 

-- linear: vestibule--> utricle ─ /saccule │, -> macula , contain otoliths

3. BPPV

-- most common vestibule disease

-- caused by otoliths floating to posterior semicircular canal, may automatically return

-- diagnosis: Dix-Hallpike test (45°, quickly lay down pt.)

-- symptoms: latency 1~5 secs, duration <30 secs, fatigability(+), nystagmus toward the ground (geotropic), clockwise when left BPPV

-- treatment: Epley maneuver

4. Vestibular neuritis

-- DO NOT affect hearing, otherwise consider labyinthitis

-- sudden onset vertigo

-- last days to weeks, full recover in 3~6 months

-- mostly non-recurrent

-- check electronystagmographic testing(ENG) with head thrust, caloric stimulation...

-- treatment: vestibular depressant, hydration, antiemetics, corticosteroids, vestibular nerve resection, rehabilitation 
-- DDx:  Ménière’s disease, vestibular schwannoma, cerebellar infarction

5. Ménière’s disease

Triad
-- sudden onset dizziness, lasting for hours
-- tinnitus
-- fluctuating hearing loss and dysacusis

-- 20~40 y/o female
-- endolymphatic cochlear hydrops (overproduction, re-aborption↓, obstruction) 
-- diagnosis: definite, possible or certain case
-- tools: otoscopy, auditory brainstem response(ABR),  electrocochleography(ECochG), vestibular findings

Blausen.com staff. "Blausen gallery 2014". Wikiversity Journal of Medicine. DOI:10.15347/wjm/2014.010. ISSN 20018762

-- treatment: similar, antihistamine(Betahistine)/ BZD, restrict salt/caffeine/nicotine/alcohol, Ca2+↓(clinnarizine), destruction(surgery or Gentamycin)

6. Audiogram
-- normal: 125- 8000Hz, at least 25dB
-- hearing loss: conduction, sensorineural, mixed
-- acute symptoms of hearing injury: pain, muffled, tinnitus 
-- audiometric hallmark: early stage--> drop in  3-6 kHz(4kHz), high pitch

7. Tinnitus
-- subjective
-- objective (hemangioma, muscle cramping)
-- mind drug use:  aspirin, diuretics, quinidine, NSAID

8. Ototoxicity
-- usually bilateral
-- aminoglycosides (streptomycin), cisplatin...

9. Sudden sensorineural hearing loss

333 rule
-- loss 30 db↑
-- 3 continuous frequency
-- progress within 3 days

-- no specific etiology, may be related to virus, vessel contraction induced ischemia, membrane rupture, autoimmune

-- treatment: vasodilators (no for BP), corticosteroids

10. Cerebellopontine angle tumors (CPA tumor); benign
-- vestibular schwannomas (78%)
-- unilateral hearing / vestibular problem
-- most sensitive/ specific test: auditory brainstem response (ABR)
-- must-do image: MRI
-- surgery if >3cm, or nerve compression (CN7, 8)