Friday, July 30, 2010

E book of the week : Role of Debriders in Otolaryngology

E book of the week:


"Role of Microdebriders in Otolaryngological surgery"


This freely downloadable e book discusses the current role of
Microdebriders in Otolaryngology.


 

Sunday, July 25, 2010

Friday, July 23, 2010

A rare case of tuberculosis tonsil

Introduction:

Tuberculosis involving the tonsil is very rare. These days it is still rare because of better milk processing techniques like pasteurization which eradicates the bovine strain of tuberculosis. Even though tonsils are situated in an exposed area where infected material like sputum and food stuffs come into contact this lesion is rare because of the following features:

1. Antiseptic and cleansing action of saliva (first and foremost)

2. Presence of saprophytic organisms in the oral cavity which prevents growth of tubercle bacilli

3. The stratified squamous epithelial lining of the tonsil also offers some degree of protection

Tuberculosis of tonsils may be:

Primary - Due to ingestion of infected milk (Bovine strain)

Secondary - Due to pulmonary infection. The coughed out infected sputum finds its way to the throat to involve the tonsils.

Diagnosis of tuberculosis of tonsil is not straight forward. It needs high degree of suspicion.

Pointers for the diagnosis of tuberculosis tonsil:

1. Asymmetric enlargement of tonsil

2. Tonsillar enlargement without exudate

3. Obliteration of crypts

4. Painful deglutition

5. Presence of enlarged mobile jugulodigastric nodes

















Clinical photograph of a patient with Tuberculosis tonsil


View the full case details from here.

Monday, July 19, 2010

Vocal cord paralysis

Definition: Vocal cord paralysis is caused by paralysis of intrinsic muscles of larynx. This is a symptom of an underlying disorder and not a disease by itself. The intrinsic muscles of the vocal cord are supplied by the vagus nerve. The term vagus means "wanderer" which is the apt term to describe this nerve becuase of its long anatomical course.

Unilateral vocal fold paralysis occurs due to dysfunction of recurrent laryngeal or vagus nerve causes a breathy voice. The breathiness of voice is caused by glottic chink which allows air to escape when the patient attempts to speak. Normal voice production is dependent on proper glottal closure resulting from bilateral adduction of the vocal cords. This adduction of vocal folds combined with subglottic air pressure causes the vocal folds to vibrate causing phonation.

you can read the full e book from here.

Thursday, July 08, 2010

Surgical management of puberphonia recent concepts

Introduction:


Mutational falsetto is also commonly known as Puberphonia. This condition is caused due to the failure of the voice to drop in its pitch from the higher levels after puberty. These patients hence suffer from lack of resonance in voice, breathiness of voice and lack of pitch variations. These patients have easy fatigability of voice and are unable to raise their voice in noisy environments.

This condition is caused due psychological problems in the patient which prevents lowering of the pitch of the voice of an adolesecent to that of a adult range. Puberphonia is more common in adolescent males and may also occur rarely in females.


The following are the probable psychological factors that could lead to the developement of puberphonia:


1. Over identification of the affected boy with his mother
2. Failure of the boy to accept his adult male role
3. Social immaturity
4. Anxiety to maintain a Soprano voice
5. Incordination of muscles of vocalization

Surgical management of Puberphonia:


When all the above conservative methods fail then surgery will have to be resorted to. Isshiki type III relaxation thyroplasty has shown promise in managing these patients. This surgical procedure lowered the pitch of voice in these patients by shortening the length of the vocal folds. In the classic Isshiki type III thyroplasty 2 – 3 mm of vertical strips of cartilage were excised on each side of midline of thyroid cartilage. This procedure caused retrusion of the middle portion of the thyroid cartilage causing a reduction in the length of the vocal folds.

Various modifications of Type III Ishikki thyroplasty have been proposed.


View the full article from here.

Anatomical changes that occur in ethmoid sinuses following FESS

Introduction:


The bony walls of paranasal sinuses demonstrate excellent degree of plasticity. This feature allows alterations in the size and dimensions of paranasal sinuses during growth phase. The process of pneumatization of paranasal sinuses begins in utero and continues through teenage years.

Causes of pathological expansile alterations of paranasal sinuses include:


1. Allergic fungal sinusitis
2. Extensive sinonasal polyposis
3. Mucocele formation
4 Benign tumors


While performing endoscopic sinus surgery it should be borne in mind that it is being performed in a setting of bony changes, with an intention to halt the expansile / contractile changes that are likely to take place.


View the full article from here.

Tuesday, July 06, 2010

Dysontogenic cysts of floor of mouth


Introduction:

Dysontogenic cysts are otherwise known as dermoid cysts. These cysts develop due to defective embryonic development. This cyst includes any cyst which are filled with sebum like material with evidence of presence of specialized skin derivatives.

Meyer's classification of Dysontogenic cysts of floor of mouth:

Meyer classified dysontogenic cysts of floor of mouth into 3 types, namely

Epidermoid

Dermoid

Teratoid

Epidermoid cyst: is usually lined with stratified squamous epithelium without adnexal structures.

Dermoid cyst: is lined with stratified squamous epithelium with the presence of adnexal structures. These adnexal structures include sebaceous cysts, hair follicles and sweat glands.

Teratoid cyst: Features of teratoid cysts include the presence of lining squamous epithelium, respiratory epithelium, dermal appendages and distinct mesodermal components.

Eventhough dysontogenic cysts can occur anywhere in the body, about 10% of them occur in the floor of the oral cavity. Congenital cysts occuring in the infancy have also been reported.


Clinical features:

These include:

  1. Dysphagia
  2. Dysphonia
  3. Stridor


Pathophysiology:

These cysts can be congenital / acquired in nature.

Congenital cysts are derived from ectodermal differentiation of multipotential cells that could have been pinched off during the closure of the anterior neuropore. Commonly accepted theory explaining congenital cysts is that it is caused due to entrapment of midline ectodermal tissue during fusion of first and second branchial arches during the third week of gestation. Lateral dysontogenic cysts are said to arise from the first pharyngeal pouch or first branchial cleft.

Acquired dysontogenic cysts can be explaine by Baker's theory. According to Baker trauma is the commonest cause of acquired dysontogenic cysts. Trauma causes implantation of epithelial cells into deep tissues. These implanted tissues results in formation of cystic cavities filled with keratin.


Differential diagnosis:

These cysts should be differentiated from:

  1. Ranula
  2. Obstructed wharton's duct
  3. Thyroglossal tract cyst
  4. Branchial cleft cyst
  5. Lymphatic malformation
  6. Pleomorphic adenoma
  7. Enlarged submental glands
  8. Prominent submental fat mass

Investigations:

Ultrasound examination will help in differentiating cystic from solid lesions. It ofcourse has the advantage of being easily available, cost effective and rapidly performed investigation.

MRI: Provides excellent soft tissue detail. It helps in differentiating mass from surrounding soft tissues. T2 weighted images of dysontogenic cysts shows hyperintense areas due to high proteinaceous content.

Treatment:

Complete excision of the mass is the ideal treatment modality. Almost all dysontogenic cysts of floor of the mouth can be approached through intraoral approach. All submental cysts should be approached through the neck. A cyst that has breached the floor of mouth musculature should ideally be approached through the neck.