The document discusses various laser and cryosurgery techniques used in ENT. It describes how lasers like CO2, KTP, and Nd:YAG use light amplification to cut, coagulate, and ablate tissue. Cryosurgery uses rapid freezing to below -30°C followed by slow thawing to destroy tissues. Both techniques are used to treat lesions, tumors, and other ENT conditions. Safety precautions are important as these techniques can damage surrounding normal tissues if not properly administered.

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