The Pyloric Sphincteric Cylinder in Health and Disease

Go to chapter: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39
Chapter 20 (page 92)

Ultrasonic Features

Direct viewing of the pyloric musculature is achieved by means of ultrasonic examination (Chap. 10). Blumhagen and Coombs (l98l) showed that a persistent contraction of the circular musculature of the "distal antrum and pylorus", creating a cylindrical muscle mass resembling IHPS, might be seen during ultrasonic examinations in infants. According to these authors, contraction of the "distal antrum" and pylorus (and not of the pyloric ring) constituted pylorospasm.

Blumhagen and Noble (l983) found that spasm of the "distal antrum and pylorus" could be differentiated ultrasonically from IHPS by measuring the single wall muscle thickness. Normally the muscle thickness in infants varies between 1.5 and 3.0 mm; in IHPS it varies between 3.0 and 6.0 mm. Whenever the single wall muscle thickness is 4.0 mm or more, it can be regarded as IHPS.

Wilson and Vanhoutte (l984) determined the true length of the pyloric muscle by means of ultrasonography in l7 normal infants; the range varied from 12.0 to 15.0 mm. Similar results were obtained by Graif et al. (l984), who found the mean length of the pylorus (pyloric musculature) to be 12.0 mm with a standard deviation of 3.7 mm. It is clear that this is the anatomical region which may contract during pylorospasm, i.e. a relatively long area which includes the pyloric ring, as opposed to an isolated contraction of the ring only. This was confirmed by Stunden et al. (l986), who measured the length of the pyloric canal in normal infants "with the pylorus in its most contracted state". The mean length of the canal was 8.3 ± 2.5mm, and on occasion it was up to 14.0 mm in length.

With longitudinal ultrasonic views of the pylorus Haller and Cohen (l986) found the length of the pyloric musculature in normal infants to be up to l8.0 mm. Ultrasonically the contraction of this muscular cylinder in pylorospasm could simulate IHPS. However, with spasm the contracted region was not quite as rigid as in IHPS, and the appearance changed on subsequent examinations.

Operative and Experimental Features

Larson et al (l967) described 10 adult cases in whom radiographs showed clear evidence of adult hypertrophic pyloric stenosis (AHPS), i.e. a cylindrical pyloric narrowing (Chap. 24). At operation the stomach was found to be normal in 5, showing that the narrowing was of a temporary, spastic nature, in other words due to pylorospasm.

During operations on 5 suspected cases of AHPS, Bateson et al. (l969) noted that on touching the pylorus with a gloved finger, the pyloric and adjacent "antral" muscle contracted, becoming hard and pale; the affected region was approximately 2.5 cm in length and resembled AHPS, but the contraction was temporary and of a spastic nature.

Keet and Heydenrych (l97l) found that electrical and mechanical stimulation of the vagus trunks in the oesophageal hiatus of the diaphragm in canines, caused a 3.0 cm long cylindrical area of contraction in the pyloric region. It corresponded exactly to the anatomical pyloric sphincteric cylinder as described by Cunningham (l906), Forssell (l913) and Torgersen (l942), lasted as long as the stimulus was applied, and was clearly of a spastic nature.

Case Reports

The following are some of the cases of pylorospasm which we have encountered:

Case 20.2. R.G., 10 day old male infant was admitted for persistent vomiting. Upper gastrointestinal barium study showed a constant, string-like narrowing 2.0 cm in length in the pyloric region, clearly limited to the sphincteric cylinder (Fig. 20.2). It was associated with a concave indentation of the base of the duodenal bulb, the appearance resembling infantile hypertrophic pyloric stenosis. At laparotomy no pyloric tumor was found. There was some kinking of the duodenum, which was corrected, and in view of the radiologic findings a pyloromyotomy was done. A naso-jejunal tube was inserted and recovery was uneventful. The final diagnosis of the pyloric narrowing was spasm of the pyloric sphincteric cylinder.

Fig. 20.2. Case R.G. Constant spasm of pyloric sphincteric cylinder, simulating infantile hypertrophic pyloric stenosis. At operation no muscular hypertrophy was found

Case 20.3. B.F., 7 day old female infant presented with persistent, bile-stained vomiting since birth. Radiological study showed a tubular narrowing 2.0 cm in length in the pyloric region (Fig. 20.3). It conformed to partial contraction of the pyloric sphincteric cylinder with a prominent impression of the pyloric muscle knot on the lesser curvature side. There was total absence of cyclical contraction and relaxation of the cylinder, the pyloric aperture being fixed in the open or patent position. The duodenal cap was normal but there appeared to be some narrowing of the remainder of the first part of the duodenum. Infantile hypertrophic pyloric stenosis could not be excluded. Laparotomy revealed partial obstruction at the duodeno-jejunal junction due to ectopic pancreatic tissue in the intestinal wall and adhesions. The pylorus showed no organic lesion. After biopsy, severance of adhesions and pyloromyotomy, recovery was complete. The pyloric narrowing was diagnosed as spasm of the sphincteric cylinder.

Fig. 20.3 A-D. Case B.F. Constant contraction of sphincteric cylinder. At operation no pyloric lesion was found

Previous Page | Table of Contents | Next Page
© Copyright PLiG 1998