Cruse J P, Edwards D A, Smith J F, Wyllie J H
Histopathology. 1979 May;3(3):223-32. doi: 10.1111/j.1365-2559.1979.tb02999.x.
The paper describes the changes in the cricopharyngeal muscle in seven cases of dysphagia resulting from obstruction at this level which was relieved by myotomy. Histological features included degeneration and regeneration in the muscle fibres with interstitial fibrosis which was severe in some of the cases. It is considered that this restrictive fibrosis is the cause of the dysphagia and that it is secondary to muscle fibre damage, the cause of which is at present obscure. Minor degrees of muscle damage and regeneration were seen rarely in controls and fibrosis was never present. There was no evidence of underlying vascular or neurological disease in six cases; the seventh had a previous history of scleroderma but this was not thought to be the cause of the cricopharyngeal lesion. The age incidence ranged from 1 to 5 years at the onset of dysphagia; in six of the seven it was 50 years or more.
