WILL TONSILLECTOMY BECOME OBSOLETE?
Sr. ENT Surgeon, Bombay Hospital, Mumbai 400 020.
There is general impression amongst the medical faculty and the public that tonsillectomy operation is likely to remove the defence mechanism of the body to develop immunity and protect the aero-digestive tract exposed to the airborne and alimentary antigens and hence they are averse to the idea of their removal.
The ‘Intra-tonsillar cleft’ in the palatine tonsil is a familiar clinical landmark for all ENT surgeons. The purpose of this paper is to suggest a new concept of understanding its role in the aetio-pathogenesis of different diseases of the tonsil and why TAR operation is justified in a few cases even in modern times.
According to Mr. Romanis Mitchner, late Professor of Anatomy, University College of London, it is not possible to distinguish between the cleft and the crypt in a cadaver as the tissues are shrivelled. The term ‘supra-tonsillar’ cleft mentioned in some old textbooks is a misnomer. The ITC is the remnant of the second branchial cleft between the second and third branchial arches. The anterior pillar of the soft palate and the antero-superior smaller portion of the tonsil are developed from the second branchial arch; the posterior pillar and bigger postero-inferior part of the tonsil, is developed from the third branchial arch (Fig. 1). There are 12-14 shallow crypts in the tonsil, which do not reach the capsule. The ‘ITC’ is a potential space lined by stratified squamous epithelium separating the two lymphoid tissues having their own separate capsules (Fig. 2).
The cleft is hardly visible in children due to hypertrophy of lymphoid tissue but it is not uncommon to see a bi-lobed tonsil. The cleft widens as age advances due to atrophy of the surrounding lymphoid tissue (Fig. 3). In middle aged patients accumulation of debris in the patulous cleft results in ‘cleft stasis’. The patients complain of halitosis and referred pain to the ear and neck on the affected side, They get symptomatic relief by evacuation of the sago like debris by pressure applied from below upwards on the anterior pillar. In old textbooks one finds mention of Tilly’s suction cup for the same purpose. The ‘cul de sac’ is re sponsible for a carrier state of recurrent diphtheria, fungus and virus infections. Benign papillomas in children and tonsiloliths in older patients are commonly seen at the cleft. The aetiology of a peritonsillar abscess seems to be due to the blockage of the cleft and not the crypt. The infection spreads by continuity into the peritonsillar space; the infection from the shallow crypt is unlikely to reach the same. It is not uncommon to see a peritonsillar abscess sometimes draining spontaneously through the cleft and getting cured (Fig. 4). The ENT surgeon is familiar to see gushing of normal saline from the cleft when injected in the peritonsilar tissue to facilitate dissection during tonsillectomy.
Grasping through the cleft to ensure its complete removal facilitates the dissection of the upper pole of the tonsil. Recurrent attacks of infection in the tonsillar stumps left inadvertently at either upper or lower pole are probably due to dissection in the wrong plane with the old guillotine technique. The most common site for tying a bleeder during tonsillectomy is at the junction of the upper third and lower two thirds in the tonsillar fossa. It seems to be the main blood supply. Unfortunately too much stress is put on the rich blood supply of the tonsil by five arteries during medical teaching; but in practice one hardly sees them at operation!
A mild crepitus felt occasionally below the angle of the lower jaw after a tonsillectomy in some adult patients seems to be due to the air entry into the lateral pharyngeal space during swallowing; the site of entry for air into the fascial space is due to the breech in the fibres of the superior constrictor where the cleft was adherent.
Unilateral enlargement of the tonsil is due to cancer starting in the cleft and then spreading centrifugal in the deep substance. The diagnosis of malignancy is confirmed by excision biopsy as repeated surface biopsies may be negative.
In Papangellou’s pharyngoplasty operation to correct rhinolalia aperta for improving speech, the lower pole of tonsil is dissected from below upwards to the level of the soft palate and transposed medially on a new raw area created on the posterior pharyngeal wall at the level of the soft palate Care is taken to preserve the blood supply from facial artery supplying the second branchial arch.
In recent times an otolaryngologist is doing far less surgeries for chronic tonsils and adenoids than before; but it still accounts for 20% of all operations. Recurrent attack tonsillitis is the most controversial indication for surgery. Removal of a known septic focus has been found to benefit patients suffering from wryneck, lumbago, skin and eye disorders. Rheumatic heart disease with valvular defects and glomerulo-nephritis has been the most common complications of recurrent upper respiratory infection. The use of a prolonged course of antibiotics for many years as prophylaxis to prevent recurrent infections is debatable. The development of drug resistance is well known. In developing countries like India the source of deep neck infection is either a septic tonsil or molar tooth. These deep infections are only amenable to bold surgery as they fail to respond even to the new generations of antibiotics. The few absolute indications for removal are perforative otitis media, obstructive sleep apnoea, a complete branchial fistula and local malignancy.
The intra-tonsillar cleft in the palatine tonsil is in fact inter-tonsillar between two portions of lymphoid tissue. The new concept based on development of palatine tonsil and its immunological function is helpful for a better understanding and advising its removal in the few cases when indicated. More over three would be far fewer diseases to study for a medical student if there were no inter-tonsillar cleft!
1. Apte NK. Intra-tonsillar cleft - a clinical landmark, The Journal of Laryngology and Otology. London. April 1963; LXXVII : 4.