RESUMEN
OBJECTIVE: An abnormal relative position of the superior mesenteric vein and artery can be present in patients with intestinal malrotation. We undertook this retrospective study to see how often we could determine the relative position of these vessels on abdominal sonograms in infants and how often abnormal position of the vessels was associated with malrotation. MATERIALS AND METHODS: We reviewed the radiology files and medical records of 337 infants with vomiting who were referred for sonography because of possible pyloric stenosis. We used sonograms and written reports to determine the position of the superior mesenteric vessels. The position was considered normal when the superior mesenteric vein was to the right of the superior mesenteric artery on transverse sonograms. The position was considered abnormal when the vein was directly ventral to the artery or when the vein was to the left of the artery. Sonographic findings were compared with results of upper gastrointestinal series when possible and with clinical outcome. RESULTS: The relative positions of the superior mesenteric vein and artery were evident in 249 (74%) of the 337 patients. Abnormal orientation of the mesenteric vessels was detected in nine patients. In five patients, the superior mesenteric vein was located to the left of the artery, and all five had intestinal malrotation. In four patients, the superior mesenteric vein was directly ventral to the artery, and one of these had malrotation. CONCLUSION: Sonographic assessment of the relative positions of the mesenteric artery and vein is an important adjunct in the examination of infants with suspected pyloric stenosis. Patients in whom sonograms show an abnormal position of the vessels should have further examination to detect malrotation.
Asunto(s)
Intestinos/anomalías , Arterias Mesentéricas/diagnóstico por imagen , Venas Mesentéricas/diagnóstico por imagen , Anomalías Congénitas/epidemiología , Femenino , Humanos , Lactante , Intestinos/diagnóstico por imagen , Masculino , Arterias Mesentéricas/anomalías , Venas Mesentéricas/anomalías , Estenosis Pilórica/diagnóstico por imagen , Estudios Retrospectivos , UltrasonografíaRESUMEN
In many pediatric centers, sonography has become the primary imaging method for the diagnosis of hypertrophic pyloric stenosis, but investigators have disagreed about which dimension of the gastric outlet is most useful and accurate. We analyzed 326 consecutive sonograms in 319 infants who presented with vomiting in order to further evaluate the sonographic criteria for the diagnosis of hypertrophic pyloric stenosis. Four observers retrospectively measured three parameters: (1) the thickness of the muscle in the wall of the gastric outlet, (2) the length of that muscle, and (3) the length of the pyloric channel. In the patients with hypertrophic pyloric stenosis, muscle thickness was 4.8 +/- 0.6 mm, muscle length was 2.1 +/- 0.3 cm, and channel length was 1.8 +/- 0.3 cm. In the patients without hypertrophic pyloric stenosis, muscle thickness was 1.8 +/- 0.4 mm, muscle length was 1.3 +/- 0.3 cm, and channel length was 1.1 +/- 0.3 cm. The mean measurement for each parameter was significantly larger in patients who had hypertrophic pyloric stenosis than in those who did not (p less than .01). However, histograms of the three parameters show significant overlap in the measurements of muscle length and channel length between the patients with and those without hypertrophic pyloric stenosis. The thickness of the muscle is the most discriminating and accurate criterion for hypertrophic pyloric stenosis.