ENT JC098: Dysphonia: Laryngitis, Voice Abuse, Tumour And Laryngeal Cancer Flashcards
Dysphonia, Aphonia, Hoarseness
Dysphonia:
- Any impairment of voice
Aphonia:
- Total loss of voice
Hoarseness:
- Rough / Noisy quality of noise
***Voice disorder (Dysphonia) =/= Speech disorder (Fluency disorder (e.g. stuttering) / Dysarthria (articulation problem))
Physiology of Speech
5 steps:
1. Airflow generator (Breath support)
- Lungs
- Intercostal muscles
- Diaphragm
- Voice production (Vibrator) —> Problem: Voice disorder (Dysphonia)
- True vocal cords - Resonance (Upper airway) —> Problem: Dysarthria
- Nasal cavity, sinuses
- Pharynx
- Oral cavity - Articulation —> Problem: Dysarthria
- Tongue
- Teeth
- Jaw movement - Speech
Conversion of airflow into sound waves
Vocal cord (5 layers):
1. Epithelium
- ***Superficial lamina propria / Reinke’s space (transparent gel-like, pliability of VF)
- provide soft floating layer to support epithelium
- sound wave can generate on epithelium - Intermediate lamina propria
- progressive ↑ in consistency
- elastic rubber band texture - Deep lamina propria
- collagen layer - Vocalis muscle
Glottic cycle (transform kinetic energy of airflow into sound waves):
Cyclical closure of vocal cord
—> Build up of subglottic pressure
—> Cyclical puffs of air
—> Bernoulli’s effect of exhaled airstream (air pressure between cords ↓ suddenly due to high air velocity)
—> Suck vocal cords together
—> Sound waves
***Causes of Dysphonia
- Organic (e.g. anatomical change in vocal cord)
- Poor breathing support
- Neurological
- Local vocal cord pathologies - Functional (e.g. muscle tension dysphonia)
- Psychogenic (e.g. conversion disorder)
- Organic causes of Dysphonia
- Poor breathing support
- Poor respiratory condition (e.g. asthma, COPD)
- Poor coordination (between voice and breath) - Neurological
- Central (e.g. Parkinsonism)
- Peripheral (e.g. RLN palsy (***Vocal cord palsy), SLN palsy) - Local vocal cord pathologies
- Benign
—> Acute laryngitis
—> **Vocal cord nodules
—> **Vocal cord polyp
—> **Reinke’s edema
—> **Recurrent respiratory papillomatosis
- Malignant (Cancer of larynx)
—> ***SCC
***Causes of Speech disorders
Organic
- Upper airway problem (Resonance)
1. Oropharynx (e.g. Tonsillar hypertrophy: “hot potato” voice)
2. Hyponasality (inadequate airflow through nose during speech)
3. Hypernasality (excessive airflow through nose during speech e.g. cleft palate)
Vocal cord palsy
Causes:
1. Idiopathic (e.g. infection of RLN)
- Brainstem lesion (RLN is from CN10 which is from brainstem)
- Pathology along ***RLN
- e.g. CA thyroid, esophagus, lung, Ortner’s syndrome (big left atrium —> compress on RLN) - Pathology involving ***Arytenocricoid joint
- e.g. dislocation after intubation, RA (∵ AC joint a synovial joint), cancer infiltration from larynx / hypopharynx - Iatrogenic (most common)
- nerve damaged during surgery (HN, thyroid, esophageal, cardiac, thoracic surgery)
Treatment:
1. Unilateral VC palsy
- Voice therapy (strengthen normal VC to push against paralysed VC)
- **Injection laryngoplasty (make paralysed VC more bulky, usually temporary, for VC that have potential to recover later)
- **Medialisation thyroplasty (permanent, place a piece of synthetic material to push paralysed VC to midline)
- Bilateral VC palsy
- ***Tracheostomy as airway protection
Vocal cord nodule***s
Always come in **pairs (∵ VC hitting each other too much e.g. overuse of voice ~ callus in hand)
- Bilateral + Symmetrical
- Junction of **Anterior + Middle 1/3 of vocal folds (only anterior / middle 1/3 is membranous (soft + vibrating + hitting each other), posterior 1/3 is Arytenoid cartilage)
Cause:
- Chronic vocal trauma —> **Localised edema (reversible) —> **Fibrosis (irreversible) —> Nodules
S/S:
- ***Breathy voice (nodules preventing complete closure of VC)
Treatment:
- ***Speech therapy +/- Excision (will recur if no speech therapy)
Vocal polyp
***Unilateral protrusion (vs nodules)
Cause:
- **Acute vocal trauma —> Burst of capillaries —> **Haemorrhagic cyst (red in colour) —> Fibrosis —> Polyp (pale in colour)
S/S:
- Breathy voice
Treatment:
- Excision
Reinke’s edema
Fluid collection in Reinke’s space (i.e. Superficial lamina propria) (~2 bags of water)
Causes:
1. ***Smoking (Smokers’ voice)
2. Laryngeal reflux
3. Hypothyroidism
S/S:
- **Effortful (need great exhalation effort to build up subglottic pressure)
- **Low-pitch (∵ VC cannot vibrate very fast)
- Rough
Treatment:
- Correct underlying causes (e.g. stop smoking) + Excision (~ liposuction of arm)
Recurrent respiratory papillomatosis (RRP)
- Cauliflower disease of VC
- ***HPV 6, 11 infection
—> In-utero transfer, Birth tract contact (Children)
—> Oral sex (Adult)
S/S:
- Hoarseness
- **Airway obstruction
- **Malignant transformation (CA larynx)
- Tracheobronchial spread
Treatment:
- Chance of spontaneous regression upon puberty
- Surgical debulking +/- Adjuvant medical therapy (e.g. IFN, Chemotherapy —> not very effective)
—> ***NO complete cure (∵ HPV DNA embedded everywhere in larynx)
Neoplastic lesions of Vocal cord
- Leukoplakia
- whitish plaque (local thickening of epithelium due to water absorption) —> ↑ risk of malignancy (5-15%) - Erythroplakia
- reddish plaque (local thickening + attracting blood vessels to bring in blood supply) —> ***high risk of malignancy
BOTH need ***Biopsy!!!
Cancer of Larynx
Risk factors: Smoking
Commonest pathology: ***SCC
S/S:
- **Hoarseness (VC no longer flat —> cannot close completely + **Bulky / Stiff VC)
- Airway obstruction
- Cervical LN metastasis
Treatment:
Early stage
1. **RT
2. **Surgery: Laser excision, Partial laryngectomy
Advanced stage (Multimodal treatment)
1. Surgery: Total laryngectomy
2. Adjuvant RT + Chemotherapy (to control LN metastasis)
***Approach to Hoarseness
History taking:
1. Smoking
- Onset / Pattern of Hoarseness
- Acute / Chronic
- Episodic / Progressive - Occupation / Vocal demand
- ***Red flag symptoms for CA larynx
- Bleeding (blood-stained sputum / saliva)
- SOB
- Dysphagia - ANY hoarseness ***>2 weeks —> refer ENT for examination!!!
P/E, Investigations:
1. Cervical lymphadenopathy
- Inspection of larynx
- Indirect laryngoscopy (vision through reflected light by dental mirror —> difficult ∵ gag reflex)
- **Flexible laryngoscopy
- **Rigid laryngoscopy with Stroboscopy
(Direct laryngoscopy: not for clinical examination, direct vision without reflection, only for intubation / foreign body removal) - TNM staging
- T: Local tumour stage (Endoscopy, CT / MRI to see infiltration)
- N: Regional LN (USG neck + FNAC to determine whether lymphocyte / carcinoma cells)
- M: Distant metastasis (CXR, Blood test, PET)
Flexible / Rigid laryngoscopy + Stroboscopy
- Trans-nasal flexible endoscope
- advantage: Less gag reflex (∵ no need to go through mouth)
- disadvantage: Inferior quality of vision (∵ limited diameter of scope —> carrying less light) - Trans-oral rigid
- advantage: Allow use of stroboscope, Better quality of image (∵ larger diameter to carry more light)
- disadvantage: Gag reflex issue
Stroboscopy:
- Voice of patient picked up by microphone —> determine **fundamental frequency (i.e. vibrating frequency of vocal cord)
- Light source emitting at / near fundamental frequency of voice (閃閃下)
—> Generate **Illusion of slow motion of VC vibration
—> Detect subtle VC lesions
