Pathology of the Head and Neck

Larynx and Hypopharynx Chapter 7 207lagenous fibres. Some inconspicuous chronic inflammatoryinfiltrate may be present around blood vessels,without evidence of vasculitis. The covering epithelium,squamous or respiratory, may be reactively hyperplastic.ISS is a chronic lifetime disease that requiresmultiple surgical dilatations for palliation [73]. Evaluationfor laryngopharyngeal reflux disease should beperformed with pharyngeal pH testing in all patients,in an attempt to clarify the aetiology of ISS [229]. Moresevere cases are managed with laryngotracheal resectionand reconstruction [369].7.3.3.8 Angioneurotic OedemaAngioneurotic oedema (ANO) is a rapidly appearing,recurrent, non-pitting oedema of the subcutaneousand/or submucosal tissues causing a life-threateningcondition, affecting the larynx, hypo-and oropharynxand oral cavity [144]. ANO can occur as a result of hereditaryand acquired deficiencies in the immune andnon-immune responses [81]. Several forms of ANO arerecognised:1. IgE-dependent, caused by pollens, foods, drugs, fungi,cold, sun and exercise;2. Complement-mediated, hereditary and acquired withdeficiency of the C1 esterase inhibitor of the complementcascade;3. Non-immunologic, direct mast cell-releasing agentscaused by different drugs and aspirin, and other nonsteroidalanti-inflammatory drugs that alter the arachidonicacid metabolism;4. Idiopathic [13].Angioneurotic oedema, either acquired or hereditary,is characterised by sudden onset with full developmentwithin a few hours and fades over the courseof 48–72 h. Gastrointestinal mucosa may also be affected,mainly in the hereditary disease, causingsevere abdominal pain, nausea, vomiting and diarrhoea.Various degrees of laryngeal oedema may bepresent, affecting mainly the anterior surface of theepiglottis, aryepiglottic folds, base of the tongue andhypopharynx [238]. Generally, ANO resolves withoutharm, but laryngeal and tracheal oedema may causeasphyxiation and remains a considerable cause ofdeath [90, 362]. The frequency of attacks in hereditaryforms varies considerably from less than 1 to 25per year. Lesions can be solitary or multiple, and primarilyinvolve the extremities, larynx, face and bowelwall [90]. Emergency treatment is required if the processleads to respiratory distress because of laryngealinvolvement.7.4 Degenerative Lesions7.4.1 OculopharyngealMuscular DystrophyOculopharyngeal muscular dystrophy (OPMD) is a lateonset,dominantly inherited, slowly progressing disease,carried by a limited expansion of the triplet of GCGnucleotides in the PABP2 gene on chromosome 14q11[43]. Although OPMD has a world-wide distribution,its prevalence is highest in patients of French-Canadianorigin [129, 155]. The onset of disease occurs in middlelife, most often presenting with ptosis and a slight degreeof ophthalmoplegia, followed later by dysphagia andoften proximal limb weakness. The disease progressesslowly, but the dysphagia may be severe and has beenreported to be a cause of death by starvation in severalcases [316]. Muscle biopsy reveals various changes inmuscle fibres, such as atrophy and regeneration with anincreased number of myocyte nuclei and their centripetalorientation. Some findings, such as intracytoplasmicrimmed vacuoles, found by light microscopy, andintranuclear filament inclusions, seen by electron microscopy,are its pathological hallmarks [316]. Hill andco-workers provided confirmation that the detection ofexpanded GCG-repeated lengths in the PABP2 gene is areliable diagnostic test for OPMD in the English population[155]. However, their results were not in accordancewith other molecular studies [43]. Simple proceduressuch as blepharoplasty and cricopharyngeal myotomyconsiderably improve the quality of life of these patients[129].7.5 Pseudotumours7.5.1 Exudative Lesionsof Reinke’s SpaceThe special anatomic framework of Reinke’s space isconsidered essential for the development of a group ofso-called exudative benign lesions of the vocal cords,including Reinke’s oedema (RO), vocal cord polyps(VCPs) and nodules (VCNs) [177, 179, 181, 238, 308].Each of three entities has its own clinical and morphologicalspecificities [85], but most of them overlap. Thecommon basic pathogenetic mechanism is blood vesselinjuries with accumulation of oedematous fluid in Reinke’sspace [85, 308].