Is there a reliable correlation between the radiologic and manometric findings for diagnosing diffuse esophageal spasm ?
M. Levesque, O. Arcangioli, E De Broucker, R Legmann (Paris)
The disease of diffuse esophageal spasm (DES), one of the motor disorders of the esophagus, is characterized clinically by the imprecise nature of its symptoms, which consist of substernal pain and/or dysphagia and whose occurrence is transient or intermittent.
The most specific manometric sign of this disorder consists of normal primary peristalsis alternating with simultaneous contractions (more than 10 %), which appear as high-amplitude, non-propagated waves lasting more than 7 seconds. The lower esophageal sphincter (LES) is usually normal, but in about 30 p. cent of cases incomplete relaxation or abnormally high tonus has been observed [3, 8].
Radiologically, esophageal transit may be normal or may display the following nonspecific features : disorganization of primary peristalsis; tertiary activity; normal activity of the LES, but possibly incomplete relaxation; and parietal thickening of the esophagus, which, though reported in several relatively old publications, is not demonstrated by modern echo-endoscopic techniques .
It is not clear whether there is any correlation between the manometric and radiologic features of motor disorders of the esophagus, nor has the role of radio-diagnosis itself in the evaluation of these disorders been clearly established. Earlier studies have shown that it is possible to detect such disorders by radiologic examination, but only in a proportion of cases. Thus, while 95 p. cent of cases of achalasia can be accurately diagnosed by radiologic examination, only 54-71 p. cent of cases of DES and 46 p. cent of nonspecific motor disorders can be so diagnosed [6, 7].
The principal defects of radiologic examination are as follows :
- the criteria for diagnosing motor disorders are imprecise because they cannot be correlated with the manometric data;
- images gathered at different times, such as those obtained manometrically, are variable;
- the investigator may not be sufficiently informed about the motor pathology of the esophagus;
- deglutition is not consistently studied by the proper technique, which involves radiologic recording of the dynamics of swallowing several mouthfuls of barium.
The first of these studies  was carried out in 17 patients suffering from DES and examined at different times by radiography and manometry. In 13 patients (76 %) radiologic anomalies of primary peristalsis (interruption or intermittent disorganization) were found, while manometry showed that fewer than one swallow in two was followed by a normal peristaltic sequence in the 17 patients studied. In the four patients with normal peristalsis observed radiologically, slightly more than one mouthful in two excited a normal contraction wave. Nevertheless, 4 of the 13 patients who did not display primary peristalsis at radiologic examination had an incidence of normal contractions of between 20 and 70 p. cent when examined manometrically.
In 12 patients, tertiary waves were observed, resulting in two-thirds of the cases in occlusion of the upper esophageal lumen exceeding 50 p. cent. In general, tertiary activity did not seem to be linked to the frequency of primary peristalsis as recorded by manometry. In a third of the cases, at least some of this tertiary activity did not correspond to the manometric data.
What emerges from this study, in which the radiologic and manometric investigations were not conducted simultaneously, is that the majority of patients with DES have abnormal transit when examined radiologically, but that the radiologic features of the disorder are not specific and the manometric data must also be taken into consideration.
In the second study, carried out by the same authors , simultaneous radio-manometric recordings were made for each of 20 subjects (4 normals, 13 with DES and 3 with other motor problems).
Of a total of 181 deglutitions studied, the concordance between the two methods was 97 p. cent and the diagnostic correlation 90 p. cent. Comparison of the speed of contraction and transit showed that, of the cases in which the interval between two contractions was less than 0.8 sec between two points separated by 5 cm, 98 p. cent were found to have abnormal esophageal transit. Only 36 p. cent of the contractions were simultaneous.
Nonsegmental tertiary activity, which may precede or accompany the primary wave, makes it impossible to anticipate the transit of the bolus. Tertiary activity does not appear in a specific fashion at manometry and is independent of the amplitude and duration of the contraction at the recording site. Conversely, segmental tertiary activity is always associated with high-amplitude contractions separated by intervals of less than 0.8 sec. These anomalies are not always specific to DES.
The suspicious radiologic signs in disorders of esophageal peristalsis are of four types: segmental tertiary contraction ; generalized esophageal contraction ; absence of motor activity; to and fro movements. Complete clearance of the esophagus is observed only in the first two situations.
It is only in the case of DES that segmental tertiary activity, associated with complete barium clearance, is observed before problems of primary peristalsis arise.
Radiology and manometry are both excellent methods for identifying DES. There is certainly a correlation between the data obtained by these two methods, provided the radiologic examination is performed correctly (study of the swallowing of several mouthfuls of barium, evaluation of the type and degree of tertiary motor activity, study of the dynamics by tape-recording or cineradiography, expertise of the radiologist). This poses the problem of the cost of the examination and the need for manometric equipment. Manometry is more specific for the evaluation of motor disorders of the esophagus, but in difficult cases the two methods are complementary, since radiologic investigation is used to assess the movement of barium in the esophagus while manometry provides quantitative information on the intraluminal pressure. Manometry has the additional advantage of providing better evaluation of LES function.