Coexistence of a Meckel's diverticulum and a urachal remnant.

Meckel's diverticulum, which is a remnant of the omphalomesenteric or vitelline duct, is the most common congenital abnormality of the gastrointestinal system. Urachal abnormalities, resulting from anomalous urogenital development, are not observed frequently and case reports are mainly represented in literature. The presence of these two congenital anomalies together is a very rare pathology. Complications arising from a Meckel's diverticulum or urachal remnant may clinically mimic acute appendicitis and other surgical pathologies. We report on a patient who underwent surgery for acute appendicitis when it was discovered that the symptoms were produced by a perforated Meckel's diverticulitis. In the course of the surgery, a urachal remnant was found to coexist with the diverticulum.

A study of the anatomic features of the duct of the urachus.

The urachus is an embryonic remnant resulting from involution of the allantoic duct and the ventral cloaca. Attaching the bladder dome to the umbilicus, this duct becomes progressively obliterated during fetal life. It may subsequently persist as different variants after birth, some regarded as normal, others as pathologic, due to incomplete closure. Six pediatric cases are reported here, and the literature on the embryology and anatomic basis of the duct is discussed. The urachus is present in nearly 100% of children at birth, with several possible shapes: tubular, fusiform or funnel. It gradually regresses and is found in only a third of adults. Its length varies from 1 to 15 cm. In our series 6 patients showed defective closure of the duct, including 3 with complete patency, 1 cyst, 1 diverticulum and 1 external sinus. Although rare, congenital pathology of the urachus requires a sound knowledge of the anatomy and embryology to distinguish normal forms from those subject to complications. It should be suspected with any lesion in the umbilical region and the appropriate treatment instituted.

Urachal remnants: sonographic demonstration in children.

On 62 of 100 pediatric bladder sonograms a small, elliptical, hypoechoic structure was observed on the middle of the anterosuperior surface of the urinary bladder. One of the these structures was removed surgically, and pathologic examination disclosed a normal urachal remnant. Since it is a common sonographic finding in children, it should not be mistaken for a pathologic process unless it is accompanied by signs and symptoms of infection or bladder obstruction.

Ultrasonography of umbilical structures in clinically normal foals.

The umbilical arteries, urachus, and umbilical vein were scanned ultrasonographically in 13 clinically normal foals that ranged in age from 6 hours to 4 weeks. Sonograms were obtained using a 7.5-MHz sector scanner transducer placed across the midline of the ventral portion of the foal's abdominal wall. The umbilical vein was scanned from the umbilical stalk to its entrance into the hepatic parenchyma. The mean (+/- SD) diameter of the umbilical vein was 0.61 +/- 0.20 cm immediately cranial to the umbilical stalk, 0.52 +/- 0.19 cm midway between the umbilicus and liver, and 0.6 +/- 0.19 cm at the liver. The urachus and umbilical arteries were scanned from the umbilical stalk to the apex of the urinary bladder and had a mean total diameter of 1.75 +/- 0.37 cm at the bladder apex. The umbilical arteries also were scanned along either side of the bladder and had a mean diameter of 0.85 +/- 0.21 cm. These measurements and the ultrasonographic appearance of the internal umbilical structures from clinically normal foals can be used as references to diagnose abnormalities of the umbilical structures in neonatal foals.

Urinary ascites: complication of umbilical artery catheterization.

In the newborn, intraperitoneal extravasation of urine from a urachal laceration may follow an attempt at umbilical artery catheterization. Clinical results of this injury are neonatal ascites, anuria, and azotemia. Herein, we describe a case of iatrogenic bladder injury with successful management following late detection. The anatomy of the urachus and bladder in the newborn are reviewed as well as clues to the diagnosis of neonatal urinary ascites.

Etiopathogenesis and biological behavior of feline vesicourachal diverticula. Don't just do something--stand there.

Asymptomatic microscopic urachal remnants located at the vertex of the urinary bladder are common in cats. Because they reduce the tensile strength of the bladder wall at this location, they represent risk factors for development of acquired macroscopic diverticula in cats with lower urinary tract disorders. Elimination of the underlying cause of lower urinary tract disease is frequently associated with resolution of acquired macroscopic vesicourachal diverticula.

Malignant urachal lesions.

Urachal cancers are uncommon malignancies with a location that often permits considerable local extension before they are discovered. The most common histological type is adenocarcinoma, which may produce mucus that is a valuable aid in diagnosis. The presence of stippled calcification in a midline abdominal wall mass is almost pathognomonic for urachal carcinoma. More commonly, however, the symptoms are less specific, such as hematuria and an abdominal mass. Many lesions are visible endoscopically and, thus, the diagnosis can be made preoperatively from a biopsy. Most treatment failures occur because the tumor is not controlled locally by the initial operation and, therefore, we recommend en bloc cystectomy with umbilectomy and pelvic lymphadenectomy unless the tumor is known to be a sarcoma or early stage (I) carcinoma. If these patients are undertreated and there is a local recurrence then the patient usually is not salvageable. Because of the difficulty in identifying the origin of a bladder adenocarcinoma, any tumor on the dome or anterior wall should be approached initially as if it were a urachal tumor.

[Relationship between the dynamics of urachal microvessels and its reduction]. / Dinamika mikrososudov urakhusa v sviazi s ego reduktsiei.

Three stages of the urachus morphogenesis, its stabilization, functional activity and involution find their reflection in all morphological characteristics mentioned. The stage of ductal stabilization is characterized by its tubular structure with lack of any definite anatomical criteria to subdivide it into certain parts. In the urachus wall, five constituents of the microcirculatory bed are differentiated, two microvessel network develop for its nutrition, external and internal. The stage of functional activity coincides with the 5th month of the intrauterine life. At that stage, the tubular structure of the urachus is fully developed and the main elements of its wall are formed. The vessel of the microcirculatory bed are definitely differentiated and the vascular diameter reaches its maximum. The stage of the urachus involution from the view-point of its anatomy is characterized by a possibility to distinguish three dynamically changing parts: obliterated, obliterating and open. During this period, a gradual but quite definite change of its histostructure occurs and gradually the differentiated functioning duct becomes a rudimentary connective tissue cord. Under such reduction in the wall layers of the duct, the diameter and number of microvessels reduce downward. This process is proved morphometrically.

Morphological studies on the fetal membranes of the normal singleton foal at term.

Of 211 consecutive thoroughbred foalings, 145 satisfied a set of criteria for normal parturition and foal viability. The fetal membranes from these and from 10 pony foalings have been systematically examined morphologically and quantitatively and the findings compared to those of other authors. Five sites on the allantochorion were consistently devoid of villi. Expulsion usually occurred with the non-villous side outermost. In 24 per cent of allantochorions the non-pregant horn was of equal length or longer than the pregnant horn. These placentae tended to be shed with the villous side outermost. All membranes contained a hippomane in the allantoic cavity. Remnants of the yolk sac placenta and extra-embryonic coelom were always present. Large vestigeal yolk sacs have previously been confused with anomalous twins. In most cases the endometrial cup sites were site recognisable, usually arranged around the umbilical cord attachment. This attachment was found on the dorsal aspect of the uterine cavity either at the junction of the horns or within the pregnant hor; rarely, it was in the non-pregnant horn. A degree of twistng of the umbilical cord is normal. In 6.2 per cent of cords small urachal dilatations were noted, resulting from flight stenosis of the urachal luman at the site of a twist. Ninety-five per cent of cords measured between 36 and 83 cm.