Thursday, February 21, 2019

RECENT ADVANCES IN OTORHINOLARYNGOLOGY

INTRODUCTION
Otolaryngology has advanced in a dramatic and rapid manner in the last decade. The advent of the operating microscope has facilitated the refinement of microsurgical techniques.

A new era was started by functional endoscopic sinus surgery, skull base surgery, and phonological surgery. The surgical advances proceeded hand in hand along with diagnostic audio vestibular and radiological investigations.
 
DIAGNOSTIC ADVANCES
Laryngeal photography : Photographic documentation has become more and more important in the upper respiratory tract. Documentation is necessary for recording 
Natural history of the illness.
Effect of treatment on the disease.
Medicolegal purposes.

The modern method of photography is done with a 35 mm single frame, single lens reflex camera with Hopkins telescopes fibreglass light conducting cable provides continuous light for visualisation.1,2

Otoscopic photography : This is required to record the status of the eardrum and the middle ear contents, binocular microscope makes it easier for a clinical photograph.
 
Techniques for visualisation of the vocal cords
Stroboscopy : It enables us to see slowed sequence of the vocal cord movements. Modern stroboscope is an extremely essential part of the voice clinic. Xenon light source is usually preferred. The most important advantage of the stroboscope is that it shows mucosal as well as ground movements of the vocal cords.9
Fibre optic laryngoscopy : It is often used in the out patient department. The larynx can be visualised under good magnification. The cord movements can be recorded and local anaesthesia is used.8
 
Advances in Imaging Techniques
Contrast enhancement CT Scan : This procedure is useful in imaging metastatic nodal disease and high resonance scanning of the temporal bone. Gadolinium enhancement is very useful for temporal bone lesions such as tumours like neuromas, paragangliomas, carcinomas and inflammatory lesions and carcinomas.
Magnetic resonance imaging : This is the investigation of choice for retrocochlear pathology. Gadolinium enhancement helps to distinguish between tumours of the sinuses. Soft tissue masses are better seen on MRI. The efficacy of magnetic resonance angiography is fast increasing and is fast replacing the conventional catheter angiography.

Newer advances in MRI like fast spin-echo very well demonstrate the normal anatomy in Otolaryngology.5
 
SURGICAL ADVANCES
Reconstructive prosthesis in the ear
There have been great advances in the surgical techniques of tympanoplasty, mastoidectomy and stapedectomy. Various implants have been used after these surgeries to give the patient a good hearing.

Metallic : These implants are bio-inert and have One of the major problems in this surgery is the cost. A multi-channel implant does cost several lakhs. Thus a reduction in cost in India will surely make a light visible at the end of the tunnel and enable more people to have access to this surgery.18
 
Lasers in ENT
The introduction of laser into routine ear, nose and throat surgery has gradually given way to a more balanced and realistic attitude to its uses and limitations. The major advantage of laser is its precise incision, haemostasis achieved and reduced post operative fibrosis and scarring.

The Carbon dioxide and Neodymium - YAG laser offer the Otolaryngologist a new perspective in the management of difficult tracheal and oesophageal problems.

The CO2 laser is used extensively in most ENT lesions. The spot size has been reduced to less than 1 mm diameter, which greatly reduces any damage to the surrounding areas. The Neodymium - YAG laser offers a vehicle for the treatment of endotracheal lesions including tracheal stenosis. This laser is of vital importance for the management of urgent respirator obstruction. The laser emission can be targeted even by a flexible endoscope. The Argon laser has shown to be extremely useful in making the footplate opening in stapedotomy. It is especially useful in revision cases, which require safe removal of scar tissue over the oval window.

Laser surgery for the oral cavity and the larynx has an extremely good precision because of the facility for the attachment of the laser beam to the microscope in ENT disease.
 
Common indications for laser in ENT

1
Oral leucoplakia : Leucoplakia is strikingly responsive to the CO2 laser. Recurrence of new patches of leucoplakia after laser treatment are also less likely. The operating microscope enables one to see much more of the targeted field. The reduced ground tissue reaction adds to the advantage of laser.
2
Oral Verrucous carcinoma : Lesions, which are 2 cms or less, are amenable to laser treatment. The results of treating small-circumscribed oral verrucous carcinomas are excellent, especially if adjacent epithelial dysplasia is limited.
3
Oral carcinomas : Removal of intra-oral carcinomas by CO2 laser is much preferred these days due to the more rapid and less painful process. Some surgeons do advocate leaving the wound open to facilitate better healing and reduced pain.
Other conditions where laser has been advocated in diseases of the Oral cavity are.
Oral and Oropharyngeal haemangiomas.
Pleomorphic adenomas.
Tonsillectomy
Uvulo-palato-pharyngoplasty.

Nasal indications : Listed are some of the commonly encountered indications in the nose which can be dealt very effectively with laser.

Nasopharyngeal Angiofibromas : These are extremely aggressive and vascular tumours of the nose and paranasal sinuses. The CO2 laser attains markedly reduced blood loss and precise incision.

Familial haemorrhagic telangiectasia : This disease has lesions which cause bleeding in the nose due to capillary dilatations. Ablation of the mucosa by laser is extremely useful to control the bleeding. However, there have been some cases of recurrence after laser.

Choanal atresia : The major advantage of the CO2 laser in these conditions in infants is the minimal tissue trauma and the bleeding. The laser beam is directed along the axis close to the floor of the nose using the inferior turbinate as a landmark. The bleeding is usually minimal and an indwelling elastic or polyvinylchloride tube can be used to prevent contraction of the new orifice.The surgery may need to be repeated at times.12

Nasal polyposis : Polyps in the nose are usually avascular and have a restricted area of the disease. Ethmoidal polyps have a high recurrence rate and laser surgery is very useful to reduce it.10
 
Common Laryngeal indications for laser
Juvenile laryngeal papillomatosis : The major advantage of laser in these conditions is a very low recurrence rate and an acceptable voice after surgery. If the papillomas are beyond the larynx, then a bronchoscopic coupler is used to deflect the laser beam.

Laryngeal polyps and granulomas : Polyps or granulomas of the vocal cords can be excised by laser or can even be vapourised. The precise incision and good post-operative voice are the main reasons why laser is mostly used in these conditions.

Congenital subglottic haemangioma : Formerly, excision of the subglottic haemangioma had a high operative mortality and likelihood of recurrence. Laser surgery has brought a totally new perspective to treatment of this condition. It provides a simple endoscopic one stage removal, minimal bleeding and may avert a tracheostomy. The absence of post-surgical laryngeal oedema facilitates early extubation.

Carcinoma in situ of the vocal cords : Laser is a satisfactory method of local control of carcinoma with a good post-operative voice and provides a quick treatment to the patient.

Invasive carcinoma of the vocal cords : The technique of CO2 laser helps in excision of the lesion for frozen section. The results of this method are comparable to radiation therapy. However, a proper case selection is required.11

Bilateral Abductor cord palsy : The surgery of cordectomy achieved a big milestone after the introduction of laser. One can do a simple cordectomy (partial or total) or an arytenoidectomy depending on the airway available between the two vocal cords. The procedure is extremely precise and with relatively minimal blood loss
.
Other laryngeal indications of laser are:

Reinke’s Oedema.

Congenital subglottic stenosis.

Laryngeal stenosis.
 
Bronchoscopic applications of CO2 laser
Lesions further down the trachea require the use of a bronchoscope. Special bronchoscopic couplers have been designed for projecting the laser beam. The coupler contains mirrors for altering the angle of the beam from the laser arm. Ventilation is maintained via the sidearm of the bronchoscope and trachea viewed through the eyepiece coupler. The newer neodymium - YAG laser is excellent especially for bronchial granulomas, papilomas, web-stenosis, and for palliative purposes in endotracheal neoplasm.13
 
Lasers in ear surgery
Laser in ear surgery was tried in 1979. Escuderol was first to describe the use of laser in seven cases of tympanoplasty. In 1980, Perkias performed laser surgery in 11 cases of otosclerosis. Laser surgery especially for otosclerosis provides pinpoint accuracy and instantaneous cauterisation minimising tissue trauma.14

The Argon laser has been more commonly used in stapedectomy as compared to the other lasers as it
1.Has a visible wavelength.
2.Accuracy of the argon laser helps to prevent inner ear damage and also causes photocoagulation.
3.A large stapedial artery transversing the oval window can be encountered with an argon laser.

Uses of laser in Ear surgery are
Perilymphatic gusher.
Revision stapedectomy.
 
Functional Endoscopic Sinus Surgery (FESS)
Functional endoscopic sinus surgery (FESS) is considered one of the most exciting development in Otolaryngology since the introduction of the operating microscope. Nasal endoscopy allows the accurate assessment of diseases and anatomical abnormalities. Endoscopes may be used to perform a wide variety of nasal surgeries like nasal polypectomy, frontoethmoidectomy, orbital decompression, hypophysectomy and surgery of the choanal atresia.
Messerklinger in 1978, was one of the pioneers of this surgery and explained the aim of the surgery as restoring the natural mechanism and maintaining as much normal anatomy as possible.15
In the past decade FESS has been performed with greater accuracy in a minimally invasive fashion, also attempting to restore normal function with very encouraging results.
 
Indications
FESS is indicated in the management of those patients with a circumscribed pathology causing obstruction of the osteomeatal complex. The disease may be in the maxillary, ethmoid, frontal or sphenoid sinuses or any area beyond the sinuses, which can be used as an approach. The common indications are:
1.Nasal polyposis.
2.Chronic sinusitis.
3.Removal of impacted foreign bodies
4.Dacryocystorhinostomy.
5.Closure of CSF leak.
6.Vidian neurectomy.
7.Optic nerve decompression.
8.Biopsy of nasal masses..
9.Cauterization of bleeding points in epistaxis.

The major advantage of the endoscope is the different angulations (30 and 70 degrees) enabling the visualisation of the different parts of the complex nasal anatomy. 0 degree Hopkins rod telescope is used in a majority of the surgery.

Diagnostic endoscopy is increasing popular procedure in the out patient department.16 
 
Soft tissue shavers in endoscopy
Powered instrumentation (soft tissue shavers and microdebrides) represent the newest advances in endoscopic surgery. These instruments offer precision in soft tissue resection.

The advantage exists not only for routine sinus surgery but also removal of nasal polyps, scar tissue, septal spurs, choanal atresia and obstructive adenoids in the nose.
 
Voice conservation techniques in Carcinoma of the larynx
Carcinoma of the larynx is one of the commonest cancers seen in Otolaryngology. Numerous procedures have been described by Oncologists all over the world.

Recent advances towards voice conservation surgeries without compromising on oncological safety are greatly appreciated. A wide range of partial laryngectomy procedures have been introduced depending on the site, extent, and staging of the disease. Partial laryngectomy can be done in glottic, supraglottic and transglottic cancers.

Glottic cancers : These malignancies are resected in a vertical plane across the glottis. The voice conservation procedures for glottic carcinomas include:
1.Laryngo fissure with cordectomy.
2.Vertical partial laryngectomy.
3.Crico-hyoido-epiglottopexy (CHEP).
4.Supracricoid laryngectomy

Supraglottic cancers : They are resected in a horizontal plane above the vocal cords without disturbing the latter part of the valeculae, pyriform fossae or arytenoids are resected depending on the extent of the disease.

Transventricular (Transglottic) cancers : These lesions are more advanced and often extend into supraglottic region or vice-versa. A wide resection is often necessary. The most commonly done procedures are
1.Supra-cricoid laryngectomy with crico-hyoidopexy.
2.Three-fourths laryngectomy.

It must be remembered that prior to any voice conservation procedure, accurate clinical assessment of the disease is most important. A CT scan or an MRI surely helps in the assessment.


BY: Manish Juveker

No comments:

Post a Comment