Ultrasound markers for prediction of complex gastroschisis and adverse outcome: longitudinal prospective nationwide cohort study.

OBJECTIVES: To identify antenatal ultrasound markers that can differentiate between simple and complex gastroschisis and assess their predictive value. METHODS: This was a prospective nationwide study of pregnancies with isolated fetal gastroschisis that underwent serial longitudinal ultrasound examination at regular specified intervals between 20 and 37 weeks' gestation. The primary outcome was simple or complex (i.e. involving bowel atresia, volvulus, perforation or necrosis) gastroschisis at birth. Fetal biometry (abdominal circumference and estimated fetal weight), the occurrence of polyhydramnios, intra- and extra-abdominal bowel diameters and the pulsatility index (PI) of the superior mesenteric artery (SMA) were assessed. Linear mixed modeling was used to compare the individual trajectories of cases with simple and those with complex gastroschisis, and logistic regression analysis was used to estimate the strength of association between the ultrasound parameters and outcome. RESULTS: Of 104 pregnancies with isolated fetal gastroschisis included, four ended in intrauterine death. Eighty-one (81%) liveborn infants with simple and 19 (19%) with complex gastroschisis were included in the analysis. We found no relationship between fetal biometric variables and complex gastroschisis. The SMA-PI was significantly lower in fetuses with gastroschisis than in healthy controls, but did not differentiate between simple and complex gastroschisis. Both intra- and extra-abdominal bowel diameters were larger in cases with complex, compared to those with simple, gastroschisis (P < 0.001 and P < 0.005, respectively). The presence of intra-abdominal bowel diameter ≥ 97.7th percentile on at least three occasions, not necessarily on successive examinations, was associated with an increased risk of the fetus having complex gastroschisis (relative risk, 1.56 (95% CI, 1.02-2.10); P = 0.006; positive predictive value, 50.0%; negative predictive value, 81.4%). CONCLUSIONS: This large prospective longitudinal study found that intra-abdominal bowel dilatation when present repeatedly during fetal development can differentiate between simple and complex gastroschisis; however, the positive predictive value is low, and therefore the clinical usefulness of this marker is limited. © 2019 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Anatomical variations in the origins of the celiac axis and the superior mesenteric artery: MDCT angiographic findings and their probable embryological mechanisms.

OBJECTIVES: To identify the spectrum and prevalence of anatomical variations in the origin of the celiac axis (CA), the superior mesenteric artery (SMA) and their major branches by using multidetector computed tomographic (MDCT) angiography. METHODS: A retrospective evaluation was carried out on 1,500 abdominal MDCT angiography images. The aortic origins of the CA, the SMA and their major branch patterns were investigated. RESULTS: Normal aortic origins of CA and SMA were noted in 1,347 (89.8%) patients. Seven types of CA and SMA origin variants were identified in 153 (10.2%) patients. The three most common variations were hepatomesenteric trunk (67 patients, 4.47%), celiomesenteric trunk (CMT) (51 patients, 3.4%) and splenomesenteric trunk (18 patients, 1.2%). An evaluation of CMT was classified as long (34 patients, 66.7%) or short (17 patients, 33.3%) subtypes, compared with the length of the common trunk. Further CMT classification was based on the origin of the left gastric artery: subtype I, 26 patients (53.1%); subtype II, 5 patients (10.2%); subtype III, 15 patients (30.6%); subtype IV, 3 patients (6.1%). CONCLUSIONS: Dislocation interruption, incomplete interruption and persistence of the longitudinal anastomosis could be the embryological mechanisms of the variant origins of the CA, the SMA and their major branches. KEY POINTS: • Aortic origins of CA, SMA and their major branches were investigated. • Celiomesenteric trunk includes several different subtypes and configurations. • Probable embryological mechanisms of origin variants in these observed arteries were discussed. • Origin variants in these observed arteries have wide-ranging health implications.

Superior mesenteric artery syndrome and its associated gastrointestinal implications.

The superior mesenteric artery (SMA) syndrome is a rare but potentially life-threatening gastrointestinal condition. Over the years, it has been referenced by several names, the most common of which is Wilkie's syndrome. These numerous terminologies have made it difficult to estimate its true frequency in the general population. Common symptoms associated with this syndrome include intermittent postprandial abdominal pain, nausea, and bilious vomiting. Our review revealed that although it is currently well-defined in the literature, the diagnosis of SMA syndrome remains challenging as other disorders can mimic its presentation. However, CT angiography is currently favored in the literature for diagnosis as it can not only show the narrowed aorto-mesenteric angle and distance, but also the extent of duodenal obstruction. In addition, we found no consensus on the preferred mode of therapy once SMA syndrome is diagnosed. The agreement among authors is that the treatment options should be based on severity of the disease, using conservative measures as the first line of therapy in mild SMA syndrome. Duodenojejunostomy is the preferred surgical approach when conservative management fails, or in severe cases.

Right paraduodenal hernia leading to bowel strangulation.

Up to half of all internal hernias are caused by paraduodenal hernia, a rare congenital midgut malrotation that accounts for less than 1% of all intestinal obstructions. The diagnosis may arise from an incidental finding on abdominal imaging or the patient may present with abdominal pain, vomiting, and obstipation. Early recognition and management of this disease entity are keys because serious complications such as bowel ischemia and infarction may result from a delay in diagnosis. We present a case involving a 14-year-old boy with gangrenous small bowel secondary to right paraduodenal hernia.

A common celiacomesenteric trunk, and a brief review of the literature.

The authors report a rare variation, a common celiacomesenteric trunk, which was observed during routine dissection of an 89-year-old Japanese female cadaver in the laboratory of the Anatomy Department. The trunk gave rise to left gastric, common hepatic, splenic and superior mesenteric arteries. The developmental significance of this variation is discussed with a brief review of the literature.

Correlations between the colic branches of the mesenteric arteries and the vascular territories of the colon.

The study, done on 100 corpses from the dissection rooms of anatomy laboratory, hinted the morphological variability of the colic arteries and their territories. Morphological variability of the colic branches derived from the mesenteric arteries (superior right colic artery -- 98%; middle right colic artery -- 88%; inferior right colic artery -- 100%; middle colic artery - 36%; superior left colic artery -- 100%; middle left colic artery -- 50%; inferior left colic artery -- 100%) allows us to give out a morphogenetic supposition related their ramification and number. Analyze of the results guide us to a tentative of setting down the vascular territories of the colon. In the beginning were established the territories of the mesenteric arteries (superior and inferior) and after that, were marked the subterritories for each colic artery. Establishing the vascular territories of the colic arteries have not only anatomical importance but also a surgical one, been known the difficult postoperatory colon's revitalization.

Congenital segmental dilatation of the colon with anorectal malformation.

Segmental dilatation of the colon is a rare entity. The authors report unique case of segmental dilatation of the cecum and ascending colon with high anorectal malformation in a newborn, and the possible embryogenesis of this condition is discussed.

Fetal superior mesenteric artery blood flow velocimetry in normal and high-risk pregnancy.

THE AIM: To record blood flow velocimetry in the fetal superior mesenteric artery in normal pregnancy and to evaluate if blood flow recordings in the vessel might predict adverse outcome in high-risk pregnancy. METHODS: The fetal superior mesenteric artery blood velocimetry was recorded in a cross sectional manner in 75 normal pregnancies between 27 and 41 weeks of gestation. Reference curves were performed for pulsatility and resistance indices. The superior mesenteric artery was also located in 48 singleton pregnancies complicated by pregnancy-induced hypertension and/or intra-uterine growth retardation. Middle cerebral artery, umbilical artery and vein and uterine artery velocimetry were also recorded. RESULTS: Superior mesenteric artery PI and RI values expressed an increase in resistance to blood flow with gestational age after 32 weeks of gestation. In all except eight high-risk pregnancies the fetal mesenteric artery PI values were within normal range. Among the pregnancies with absent or reversed blood flow in the umbilical artery, all had abnormal mesenteric artery pulsatility index (PI) (> 97.5th percentiles), one fetus died intrauterine and two others died after delivery due to prematurity, growth retardation and necrotizing enterocolitis. In the remaining fetuses with increased mesenteric artery PI, necrotizing enterocolitis was diagnosed in three cases. CONCLUSIONS: Increased vascular resistance in the mesenteric artery might be a late sign of fetal circulation redistribution and frequently related to necrotizing enterocolitis in the newborn.

Superior mesenteric artery blood flow velocimetry: cross-sectional Doppler sonographic study in normal fetuses.

Our objectives were to describe the flow velocity waveform of the fetal superior mesenteric artery and to establish a nomogram for its pulsatility index. In a cross-sectional study using color Doppler ultrasonography, superior mesenteric artery flow velocimetry was investigated prospectively in 96 healthy fetuses of between 14 and 37 weeks of gestation. In normal fetuses the pulsatility index measurements showed a slight but insignificant increase over the course of gestation (r = 0.26; P > 0.5). The lowest mean +/- standard deviation for pulsatility index in the superior mesenteric artery was 1.86 +/- 0.45 (95% confidence interval 1.67-2.06), recorded between 18 and 21 weeks' gestation. Thereafter the pulsatility index increased to 1.94 +/- 6.4 (95% confidence interval 1.74-2.8) at 22 to 25 weeks, and from weeks 26 to 29 it increased to 2.18 +/- 0.52 (95% confidence interval 1.91-2.46). During the third trimester and at term, the mean pulsatility index of 2.23 +/- 0.32 (95% confidence interval 1.43-3.03) did not change significantly with gestational age. In normal fetuses, except for the early stages, a relatively stable vascular resistance of the intestinal circulation was found. The application of this nomogram in clinical practice may facilitate evaluation of intestinal perfusion in compromised fetuses with blood flow centralization.

Superior mesenteric artery Doppler velocimetry and ultrasonographic assessment of fetal bowel in gastroschisis: a prospective longitudinal study.

OBJECTIVE: Our purpose was to determine whether Doppler velocimetry of the superior mesenteric artery and its mesenteric branches and ultrasonographic assessment of bowel can predict postnatal outcome in fetuses with gastroschisis. STUDY DESIGN: The normal reference range for the superior mesenteric artery pulsatility index was determined by studying 161 normal fetuses. Over a 24-month period superior mesenteric artery pulsatility index, superior mesenteric artery mesenteric branches systolic/diastolic ratio, bowel diameter, and bowel wall thickness were prospectively and longitudinally obtained from 17 fetuses with gastroschisis. Poor neonatal outcome was defined by bowel resection or staged repair of the defect or a hospital stay > 50 days. RESULTS: Doppler velocimetry of the superior mesenteric artery and its mesenteric branches proved minimally useful in prognosticating neonatal outcome. No difference was found in the superior mesenteric artery pulsatility index between the good and poor neonatal outcome groups (p = 0.99). Longitudinal data analysis on all fetuses with gastroschisis showed an increase in bowel diameter with advancing gestation (p < 0.0001). A greater rate of increase in bowel diameter with advancing gestation was noted in the poor-neonatal-outcome group compared with the good-neonatal-outcome group (p < 0.01). Mean bowel diameter obtained before delivery was significantly greater in the poor-neonatal-outcome group (p = 0.03). Bowel diameter obtained at 28 to 32 weeks was the best predictor of poor neonatal outcome. A cutoff value of bowel diameter > 10 mm at 28 to 32 weeks had a sensitivity of 83%, a specificity of 88%, a positive predictive value of 83%, and a negative predictive value of 88% for poor neonatal outcome. CONCLUSIONS: Doppler velocimetry of the superior mesenteric artery and its branches is not predictive of poor neonatal outcome in fetuses with gastroschisis. A bowel diameter > 10 mm between 28 and 32 weeks appears to be the best predictor of poor neonatal outcome. This newly defined variable warrants further investigation given its significant predictive power.

Blood flow velocity waveforms of the abdominal arteries in appropriate- and small-for-gestational-age fetuses.

The aim of this study was to describe flow velocity waveforms of abdominal arteries in the appropriate- and small-for-gestational-age fetus. Splenic artery, superior mesenteric artery, hepatic artery and renal artery velocity waveforms were obtained from 57 appropriate-for-gestational-age and nine small-for-gestational-age fetuses with color flow Doppler ultrasonography. The pulsatility index was used to quantify the arterial waveforms. Repeated measure analysis of variance indicated significant differences in the pulsatility index values in both the appropriate-for-gestational-age and small-for-gestational-age fetuses. A multiple comparison test revealed a significantly lower value for the pulsatility index in the splenic artery when compared to that of the other vessels for both the appropriate- and small-for-gestational-age fetuses. In the small-for-gestational-age fetuses, a lower pulsatility index value was observed at the superior mesenteric artery level when compared to the renal artery. Because of its lower frequency of successful insonation, the hepatic artery was not considered for the analysis. In the normal fetus, the splenic artery had the lowest pulsatility index when compared to the other arteries we investigated. This difference remained in small-for-gestational-age fetuses, reflecting a lower vascular resistance at the fetal spleen in both normal and small-for-gestational-age fetuses. It appears that in small-for-gestational-age fetuses the renal artery has a higher pulsatility index than the superior mesenteric artery, suggesting a preferential distribution of blood flow to the bowel.

Congenital anomalies of the portal venous system--CT appearances with embryological considerations.

The portal vein is formed by the union of the splenic and superior mesenteric veins behind the neck of the pancreas. This system is derived from the vitelline veins, a component of the extraembryonic venous system. In this paper we report three cases, each of which illustrates a congenital variant of the portal venous system, describe their computed tomography appearances and discuss the embryological processes accounting for these anomalies.

Arterial vascularization of the terminal ileum in human fetuses.

In 67 human fetuses of the crown-rump length from 58 mm to 285 mm (10 to 28 weeks of fetal age) the variability of the arterial vascularization of the terminal ileum was studied using the injection method. Three main angiomorphological types were distinguished on the basis of the frequency of occurrence of the ileocolic artery and the superior mesenteric artery ramifications and their contribution to vascularization of this part of the alimentary canal. Most frequent was found type I [46.3%] in which arterial supply of the terminal ileum stemmed from the recurrent ileal artery only or from the recurrent ileal artery and the superior recurrent artery. The type II [43.3%] was observed less frequently. In this type the terminal ileum was supplied by the recurrent ileal artery and the ileal branch of the ileocolic artery. In the most seldom type III [10.4%] the terminal ileum was vascularized by the stem of the superior mesenteric artery. The results were compared with those reported by other authors who studied the similar problem in adults.