Role of lasers and cryosurgery in ENT

1. Dr Manpreet Singh Nanda
Associate Professor ENT
MMMC&H Solan

2.  LASER – Light Amplification by Stimulated
Emission of Radiation
 Laser system – compact tube in which
medium of laser can be filled. Foot control
to use for appropriate period
 Principle
 Vaporizes the tissue
 Cuts (make incision)
 Coagulates blood vessels
 Break stones – lithotripsy, destroys cancer
cells

3.  Types of lasers
 Solid – Nd:Yag, KTP
 Gas – CO2, argon, helium-neon
 Depending on wavelength
 Visible – 380-760 nm
 Argon 488-514 nm blue colour, KTP 512nm
blue green colour
 Invisible
 UV zone – 1-380nm
 Infrared - > 760 nm - Nd:Yag 1064 nm, C02 –
10600 nm

4.  Argon laser
 Can be delivered by optic fibres
 Vascular lesions - haemangioma,
telengectasia
 Ear – stapedotomy, lysis of middle ear
adhesions, tympanoplasty graft
 Diode laser
 600-1000 nm
 Cheaper
 Turbinate reduction, DCR, tonsillar ablation
 Can be delivered through optic fibres

5.  KTP 532 laser – Potassium-Titanyl-Phosphate
 Use in endoscopic surgery through hand held
probe, delivered through optic fibres
 Ear – stapedotomy
 Nose – FESS, epistaxis, turbinate reduction,
telengectasis
 Oral cavity – leukoplakia, erythroplakia, T1
lesions, advanced tumours for debulking, SMF for
treating trismus, UPPP
 Larynx – MLS, T1 ca, laryngocele, stenosis
 Bronchoscopy – to temove tracheobronchial
secretions

6.  Nd:Yag laser
 Neodymium:Ytrium-Aluminium-Garnet
 Colourless, can pass through optic fibres
 Coagulative, but poor precision – can cause
damage to surrounding tissue
 Can be used along with CO2 laser
 Obstructive malignancy trachea, bronchi,
oesophagus
 Vascular lesions like telengectasia
 Lymphangioma
 Turbinate hypertrophy

7.  CO2 laser
 Carbon dioxide
 Medium used – mixture of co2, nitrogen and
helium neon gases
 Colour – red light of helium neon
 MC in ENT
 Good precision
 Cant pass through flexible endoscopes so need
articulating arm
 Can be attached to microscope making hand free
 Vaporizes tissue

8.  Ear – stapedotomy, acoustic neuroma
 Nose – telengectasia, rhinophyma, choanal
atresia, turbinate hypertrophy
 Oral cavity – leukoplakia, erythroplakia,
small sup cancers, debulking of large
tumours
 Oropharynx- recurrent tonsillitis, T1 tumours
 Larynx – papillomas, webs, stenosis,
leukoplakia of cord, arytenoidectomy, T1 ca
 Trachea and bronchi – debulking of malignant
tumours

9.  Advantages of lasers
 Easy and rapid ablation of tissue
 Excellent haemostasis
 Little surrounding tissue damage
 Minimal post op pain and oedema due to
action on peripheral nerves
 Faster post op recovery
 Blocks lymphatics so prevent metastasis

10.  Disadvantages of lasers
 High cost of purchase and maintenance
 Need special training
 Biopsy cant be taken
 Hazards – ET tube fire, electric shock, eye
injury, skin injury
 Chemical hazards, plumes (vaporized cell
contents)
 Damage to vocal cords
 Tracheal perforation

11.  Safety precautions
 Education and training of staff including
surgeons, anaesthesists, nursing, technicians
 Protection of eyes
 Eye glasses with side protection and different
colours (Nd:Yag – blue, co2- plain) worn by those
working in OT. Parient eye covered with double
layer of saline soaked eye pads/bands
 Protection of patient skin by saline soaked
towels, pads, sponges which are moistened
periodically
 Evacuation of smoke produced by laser
vaporization of tissue by using 2 suctions – 1 for
blood and mucus other for smoke and steam

12.  Anaesthesia gases and equipments –
prevention of ET tube fires
 Use only non inflammable gases like
halothane (safest) or ether
 Use red rubber or silicone tube wrapped with
reflective metallic (aluminium) foil,
protected with saline soaked cotton
 Cuff of tube inflated with saline water
coloured by methylene blue – warns during
leakage of cuff
 Use jet ventilation with no cuff

13.  ET tube fire
 Immediately stop ventilation, pour saline
with syringe and remove tube.
 Restore airway with new tube.
 Give IV steroids
 Perform repeated bronchoscopies to
ascertain damage
 A bowl filled with saline and a syringe should
be kept in table while using lasers
 Laser OT should be labelled and isolated
with no entry or exit allowed except ot
staff

14.  Principle
 Injection of photosensitizing agent – DHE
(dihematoporphyrin ether) IV into malignant site
and exposing the site to lasers (argon laser) ->
activates the agent leading to destruction of
cancer cells and sparing of normal tissue
 Indications
 Treatment of ca larynx, nasopharynx,
aerodigestive tract and endobronchial region
 Recurrent ca after CT/RT/surgery
 S/E – photosensitivity so wear sun protective
clothing on exposure to sunlight

15.  Principle
 Use of electromagnetic waves of high frequency
through a hand held probe which is inserted into
tissues -> cuts and coagulates tissues with
minimal normal tissue damage and scarring
 OPD procedures with fewer complications
 Indications
 Inferior turbinoplasty
 Surgery on soft palate for sleep apnoea and
snoring
 Surgery on base of tongue for snoring, lingual
thyroid

16.  Tonsillotomy
 MLS
 Myringotomy
 Treatment of rhinophyma

17.  Intermittent inhalation of 100% oxygen in
chamber with pressure above 1 ATA
(atmospheric absolute)
 Indications
 Adjunct treatment of sudden SNHL – patients
with ssnhl > 41 db within 14 days of onset of
symptoms – 100% oxygen at 2-2.5 ATA for 90
minutes daily for 10-20 sittings (6 sittings/
week) – increases amount of oxygen in
tissues by diffusion

18.  Tinnitus
 Noise induced hearing loss/ acoustic trauma
 Malignant otitis externa
 Non healing wounds
 Compromised skin grafts and flaps
 Crush injury
 CO poisoning
 Decompression sickness

19.  Rapid cooling or freezing of tissues at v low
temperature at -30 degree celsius followed
by slow thawing leads to destruction of
tissues
 Types
 Open system
 Direct application of refrigerating chemicals
like liquid nitrogen sparay, co2 snow
 Closed system
 Using cryoprobe ( available in various sizes
and designs and produces tip temperature of
-70 degree celsius)

20.  Based on Joule Thomson principle – rapid
expansion of compressed gas through a small
hole produces healing
 Gas used are – liquid nitrogen, nitrous oxide, co2
 Indications
 Head and neck tumours
 Benign vascular lesions
 Premalignant lesions
 Reduction of turbinates, allergic rhinitis
 Tonsillitis

21.  Herpetic, apthous ulcers in oral cavity
 Meniere’s disease
 Rhinosporodiasis
 Nasal polyp
 Epistaxis
 Pathology
 Tissue destruction by intracellular dehydration,
denaturation of lipoproteins, thermal shock, vascular
stasis of arterial and venous blood and
cryoimmunisation (formation of antibodies against
tissues)

22.  Procedure
 Anaesthesia – LA/ sedation/ no anaesthesia as
tissue freezing causes numbness
 Cryoprobe applied for 2-8 minutes leading to
rapid freezing
 Freezed tissue allowed to thaw slowly
 Procedure repeated once or twice
 Healing by secondary intention with necrotic
stump fall in 3-6 weeks

23.  Advantages
 Safe procedure
 No need for GA
 OPD procedure
 No excision needed
 Low cost
 Minimal side effects
 Can be tolerated by elderly
 Manage patients with bleeding disorders
 No haemorrhage

24.  Disadvantages
 Excision biopsy not possible
 Cant assess margins of tumour
 Need multiple sittings
 Depth of freezing unpredictable
 Causes skin pigmentation and loss of hair –
due to destruction of hair follicles
 With lasers decline in use