What is the role of the pharyngeal constrictors in pharyngo-esophageal dysfunction ?
P. Gehanno (Paris)
If swallowing is to proceed harmoniously, there must be the conjunction of a propulsive phenomenon associated with contraction of the pharyngeal constrictors dispatching the alimentary bolus towards the esophagus and the permissive phenomenon of opportune opening of the upper esophageal sphincter, represented by the cricopharyngeus muscle.
From time to time, both structures are affected by the same disease, and here the term «pathology of the pharyngo-esophageal junction» is justified. The prototype is represented by myopathies such as Steiner's disease, where histologic studies show a common and specific involvement of the cricopharyngeus and the constrictors of the pharynx.
At other times, however, the dysfunction involves only one of the two components of this mechanism, either hypopharyngeal propulsion or opening of the upper esophageal sphincter.
For lack or proper clinical investigation and manometric study, and also — it must be admitted — because surgical treatment can only be directed to myotomy of the cricopharyngeus, there is a more or less conscious failure to appreciate the role played by the pharyngeal constrictors.
True, in some cases, as has been widely discussed, there are asynchronisms of the upper esophageal sphincter or incomplete relaxations which may account for a high dysphagia, though without the etiopathogenic mechanism of this pathology of the sphincter being well understood, but often it is the constrictors that are responsible.
An isolated paralysis of the pharyngeal constrictors with normal functioning of the upper esophageal sphincter may be noted in bulbar softenings, as in Wallenberg's syndrome, bulbar poliomyelitis, compression by a tumor at the posterior lacerate foramen, or accompanying unilateral section of the 9th and 10th cranial nerves. This constrictor paralysis, which may be responsible for absolutely total aphagia, even for saliva, should be recognized clinically by the demonstration of immobility of the posterior pharyngeal wall, and manometrically by the absence of pharyngeal pressure waves during deglutition. If this is isolated, the patient must not be promised a cure of his dysphagia by undergoing a superior sphincterotomy.
However, the literature presents contradictory results in these cases, where good results from myotomy of the upper esophageal sphincter were numerous nevertheless, but no analysis of the failures is possible in the absence of regularly recorded manometric findings. A very large review of the published series [1] clearly illustrates this difficulty in assessing the efficacy of sphincterotomy, in so far as there is not always a precise knowledge of the anatomic and functional structures involved in the disorders of function.
In a series of 10 cases (table I), where manometry had shown only paralysis of the pharyngeal constrictors without dysfunction of the upper esophageal sphincter, we found 6 failures and 4 only moderate results, even though the sphincterotomy had been verified by electromanometry postoperatively. Hence, in these high dysphagias, it is always essential to perform manometry and, if it appears during manometry that there is a paralysis of the upper esophageal sphincter, either not to perform sphincterotomy, because it will be of little use, or to warn the patient carefully that this procedure will probably not be curative.
Table 1.
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N° of cases |
Results |
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Amyotrophic lateral sclerosis |
2 |
Failure |
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Bulbar poliomyelitis |
1 |
Moderate |
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Wallenberg syndrome |
3 |
2 failures |
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I moderate |
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Unilateral surgical section of the nerve (X, XI) |
2 |
I failure |
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1 moderate |
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Compression by a tumor (X, XI) |
1 |
1 moderate |
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Unknown |
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1 |
Failure |
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10 patients |
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10 myotomies : |
5 failures |
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4 moderate |
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Reference