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S W Beasley

Publications and source records attributed to S W Beasley.

At least 55 records · Page 3Linked to original sources
PubMed1998

Colo-colic intussusception in Henoch-Schönlein purpura.

Intussusception is the commonest surgical complication of Henoch-Sch onlein purpura (HSP), occurring in 1.3%-13.6% of affected children. Colo-colic intussusception is a rare occurrence in HSP, with only three other reported cases. Intussusception in HSP almost always originates in the ileum (90%) or jejunum (7%), and more than one-half of cases (58.4%) are confined to the small bowel. This is in contrast to idiopathic intussusception, where the majority (80%-90%) are ileo-colic and can be diagnosed and reduced by contrast enema.

Child↗
PubMed1998

Preliminary evidence that cell death may contribute to separation of the trachea from the primitive foregut in the rat embryo.

BACKGROUND/PURPOSE: The embryogenesis of many congenital tracheoesophageal abnormalities has been elucidated poorly, mainly because of an incomplete understanding of the normal mechanism of separation of the primitive foregut into the trachea and esophagus. There has been controversy about the existence and significance of the so-called tracheoesophageal septum. This study investigates the normal mechanism of tracheoesophageal separation in the rat. METHODS: Timed-pregnant Sprague-Dawley rats were killed on gestational days 11 to 16, respectively (the day on which the vaginal smear showed sperm was considered day 0 of gestation). Thirty-six embryos (six embryos from each age group) were fixed in 10% formalin. Fixed embryos from gestational day 13, 12, and 11 were sandwiched in melted agar to facilitate proper orientation before being processed. Half of the fetuses from each age group were sectioned serially in a transverse plane and the other half in a sagittal plane. The histological sections were stained with H&E. RESULTS: On gestational day 11, the foregut appears as a ventrodorsal slit in transverse section. Below the primitive pharynx, the epithelial cells on the ventral part of the foregut are actively proliferating, producing two lateral epithelial bulges (primitive bronchial buds). The epithelial cells of the dorsal aspect of the foregut show no sign of active growth. On day 12, the proximal trachea still shares a common lumen with the foregut. The distal trachea, the tracheal bifurcation, and both primary bronchi are recognized easily. At the point of tracheoesophageal separation, there is obvious debris of dead epithelial cells and condensed nuclei. These appearances were specifically located around the so-called tracheoesophageal septum and nearby grooves, resulting in enfolding cristae. There was no cell proliferation or inflammatory response in this region. On gestational day 13, the separation of the trachea and esophagus was almost complete. CONCLUSION: The present study demonstrates that a specific and consistent pattern of cell death in the region of the "tracheoesophageal septum" produced enfolding cristae that may be part of the mechanism of separation of the trachea and esophagus.

Animals↗
PubMed1998

Understanding tracheomalacia.

Tracheomalacia is an abnormality of the trachea that probably is present to some degree in all infants and children with oesophageal atresia. It causes the trachea to collapse during breathing, leading to obstruction of the upper airway. Our knowledge of the structural abnormalities underlying tracheomalacia is limited, mainly because patients with oesophageal atresia usually survive. Recently, the Adriamycin-induced rat model of oesophageal atresia and tracheomalacia has clarified some aspects of its pathology and the factors which may influence its development. The rat model suggests that the same detrimental factors that cause oesophageal atresia might also affect the development of the trachea, and that anomalous great vessels may exacerbate the severity of tracheomalacia locally.

Airway Obstruction↗
PubMed1998

Intra-abdominal manifestations of Henoch-Schönlein purpura.

Gastrointestinal involvement occurs in approximately two thirds of children with Henoch-Schönlein Purpura (HSP) and usually is manifested by abdominal pain. Abdominal symptoms precede the typical purpuric rash of HSP in 14-36%; the symptoms may mimic an acute surgical abdomen and result in unnecessary laparotomy. Major complications of abdominal involvement develop in 4.6% (range 1.3-13.6%), of which intussusception is by far the most common. The intussusceptum is confined to the small bowel in 58%; its frequent inaccessibility to demonstration by contrast enema means that ultrasonography is the investigation of choice. Ultrasonography complements serial clinical assessment, clarifies the nature of the gastrointestinal involvement and reduces the likelihood of unnecessary surgery. Bowel ischaemia and infarction, intestinal perforation, fistula formation, late ileal stricture, acute appendicitis, massive upper gastrointestinal haemorrhage, pancreatitis, hydrops of the gallbladder and pseudomembranous colitis are seen infrequently. Earlier diagnosis and prompt treatment of intra-abdominal complications has reduced the mortality from 40% to almost zero.

Abdominal Pain↗
PubMed1997

Timing and embryology of esophageal atresia and tracheo-esophageal fistula.

BACKGROUND: The embryology of tracheo-esophageal anomalies is controversial. The development of an adriamycin-treated animal model has enabled improved understanding of the embryogenesis of these anomalies. Using this model, we aimed to describe the events leading to esophageal atresia and tracheo-esophageal fistula. METHODS: Timed-pregnant Sprague-Dawley rats were injected daily with adriamycin intraperitoneally at a dose of 2 mg/Kg on days 6-9 of gestation. Histological sections were prepared from 96 experimental and 34 control rat embryos at 11-14 days gestation (plug day = day 0). RESULTS: The tracheal bud failed to develop normally from the foregut, leaving the foregut to give origin to both bronchi and differentiate into the respiratory system, and then continue as a fistula to the lower esophageal segment. Dorsal pouching of the proximal foregut, which is seen clearly on day 13, is responsible for the development of the upper esophageal segment. CONCLUSIONS: We conclude that failure of the tracheal bud to develop normally from the primitive foregut is the main event which leads to the tracheo-esophageal anomalies. As the proximal part of the primitive foregut develops primarily into a trachea rather than an esophagus, the anomaly of the esophagus could be described as agenesis instead of atresia.

Animals↗
PubMed1997

Rare pulmonary manifestations of tuberous sclerosis in children.

Tuberous sclerosis is one of the rare neurocutaneous syndromes and may involve organs other than skin and brain. Pulmonary involvement is uncommon and predominantly affects women of childbearing age. Those affected present with dyspnea or spontaneous pneumothorax from cystic or fibrous degeneration of the lung. Males are affected very rarely. This paper describes another manifestation of pulmonary involvement in tuberous sclerosis, namely, recurrent intrapleural cysts in a young boy.

Child↗
PubMed1997

The effects of Down syndrome and other chromosomal abnormalities on survival and management in oesophageal atresia.

Recognisable chromosomal abnormalities occur in over 5% of patients with oesophageal atresia (OA). In a review of 670 patients with OA chromosomal abnormalities were identified in 35 (5.2%), of whom 16 had trisomy 18 and 12 had trisomy 21. In patients with trisomy 18, the diagnosis should be suspected on clinical grounds and confirmed on analysis of chromosomes; no active treatment of the OA is justified because of the extremely poor prognosis. In Down syndrome (DS) 50% will have pure OA with no tracheo-oesophageal fistula. In addition, many of these infants will have associated anomalies typical of those normally seen in DS, eg., Hirschsprung's disease, duodenal atresia, and congenital heart disease. Despite treatment, OA with DS has a high mortality.

Abnormalities, Multiple↗
PubMed1997

Cardiovascular malformations in rat fetuses with oesophageal atresia and tracheo-oesophageal fistula induced by adriamycin.

Associated congenital anomalies have emerged as the most significant prognostic factor in babies born with oesophageal atresia and/or tracheo-oesophageal fistula (OA-TOF). The most frequently encountered groups of anomalies are cardiovascular (CV) and gastrointestinal, the former being more significant from a prognostic point of view. Some, such as a right-sided aortic arch (RAA), vascular ring, or major heart defects, may alter the timing and surgical approach for the repair of OA-TOF or adversely affect the prognosis. The rat fetal OA model induced by adriamycin (Adr) has been described previously. In the present experiments, information was sought regarding the incidence and type of CV abnormalities in fetal rats obtained from Adr-treated dams. OA-TOF was induced in 24 of 36 fetal rats from Adr-treated dams. DV abnormalities were found in 18 (75%) OA-TOF fetuses and 10 (83%) Adr-treated fetuses without OA-TOF. The difference was not significant (P >0.05). The most frequently found anomalies were ventricular and atrial septal defects. A RAA was present in 8/36 fetuses and a double aortic arch in 2/36. A patent ductus arteriosus was present in all treated fetuses compared with two-thirds of controls. The findings in the present study emphasise the importance of CV anomalies in association with OA, and reinforce the value of the Adr-induced rat fetal OA model by adding to our knowledge of the basic embryogenesis of both OA and CV anomalies.

Abnormalities, Multiple↗
PubMed1997

Congenital caecal cystic duplication presenting with caecal volvulus in an elderly woman.

Congenital caecal cystic duplication of the gastrointestinal tract usually present during infancy or young childhood. We have identified a patient who presented at 91 years of life with a caecal volvulus caused by a large communicating caecal cystic duplication. Review of the literature shows that caecal cystic duplications become symptomatic early when they cause complications, but until this report, volvulus was not a recognised presentation of caecal cystic duplication.

Aged↗
PubMed1997

Tracheomalacia with esophageal atresia and tracheoesophageal fistula in fetal rats.

BACKGROUND: Many patients who have esophageal atresia and tracheoesophageal fistula (EA-TEF) have associated tracheomalacia, which is thought to be one of the reasons for respiratory complications after surgical correction of the abnormality. METHODS: In this study, tracheas from Adriamycin-induced EA-TEF fetal rats were examined histologically and relevant cross-sectional parameters of the tracheas were measured. RESULTS: The tracheal lumen in tracheomalacia was small and irregular, losing its normal "D" shape. In most rats, the cartilaginous ring was broken into two to four segments, making the trachea lose its rigid support. The submucosa was thickened with prominent bulging of its membranous part into the tracheal lumen. The ratio of the inner luminal cross-sectional area to the outer tracheal cross-sectional area in EA-TEF rats was 15.7%, compared with a control ratio of 47.2%. In EA-TEF rats, the length of the cartilaginous ring was significantly shortened (P < .001), but not the length of membranous trachea, thus resulting in a cartilaginous/membranous (C/M) ratio of 1.55:1, markedly lower than that of normal rats (4.34:1, P < .001). The reduction of anterior-posterior diameter of the tracheal lumen was more marked than that of the transverse diameter. CONCLUSIONS: These observations suggest that the trachea in EA-TEF rats has a smaller lumen and is more flaccid than normal, making it prone to airway obstruction. The fact that tracheomalacia developed only in fetuses who had EA-TEF indicates that the factors that result in EA-TEF also cause tracheomalacia.

Airway Obstruction↗
PubMed1997

The vagus and recurrent laryngeal nerves in the rodent experimental model of esophageal atresia.

BACKGROUND: After surgical correction of their esophageal atresia and tracheoesophageal fistula (EA-TEF), many patients exhibit evidence of esophageal dysmotility. Controversy exists as to whether the esophageal motility disorders result from denervation caused by surgery or from an inherent abnormal innervation of the esophagus. METHODS: The present study used an Adriamycin-induced EA-TEF fetal rat model to trace the course and branching of both the vagus and recurrent laryngeal nerves. Abnormalities observed in EA-TEF rat fetuses include: (1) fewer branches from both recurrent laryngeal nerves; (2) deviation of the left vagus from its normal course below the aorta, passing behind the fistula to approach and join with the right vagus to form a single nerve trunk on the right side of the esophagus; (3) relatively few branches from the single vagal nerve trunk (composed of fibers of the left and the right vagus) on the surface of the lower esophagus. CONCLUSIONS: Fetuses affected by EA-TEF have inherent abnormalities in the course and branching pattern of the vagus nerves as they descend through the thorax, culminating in a deficient extrinsic nerve fiber plexus in the lower esophagus. These observations may account for the esophageal motility disorders seen in patients who have EA-TEF even before surgical intervention.

Animals↗
PubMed1997

The cost benefit of changing protocols in the management of intussusception.

BACKGROUND: At a time when pressure is being applied to healthcare systems to reduce costs and improve efficiency, both the medical and financial implications of changing practices need to be documented. METHODS: A review was undertaken of 703 patients with intussusception, treated during a 10-year period from 1983. RESULTS: This review showed that changes to the protocol for the management of intussusception have not only benefited the patient by reducing the morbidity and the operative rate, but also have led to a reduction in the length of hospital stay, providing significant cost savings to the health system. The reduction in the operative rate accounts for an estimated annual saving at the Royal Children's Hospital of $139,000. CONCLUSIONS: Improvements in the management of intussusception have resulted in significant reductions in the costs of treatments. The recent diagnosis-related group casemix funding arrangements mean, however, that the Royal Children's Hospital benefits more financially from inappropriate operative management of intussusception, than from non-operative management. Funding arrangements should not discourage optimal treatment.

Barium Sulfate↗
PubMed1997

Handlebar injuries in children: patterns and prevention.

BACKGROUND: Bicycle handlebar injuries in children are a significant cause of abdominal trauma. The present study documents 32 children with handlebar injuries who were managed at the Royal Children's Hospital over a 5-year period, and suggests a design change to bicycle handlebars which may reduce the severity of injury. METHODS: A retrospective review of all the children admitted to the Royal Children's Hospital with handlebar injuries between January 1990 and January 1995 was undertaken. The age, sex, nature of injury, length of hospital stay and management were recorded. RESULTS: Thirty-two children with blunt abdominal trauma or lacerations resulting from handlebar injuries were identified. Injuries included: splenic trauma (9); liver trauma (4); traumatic pancreatitis (3); transection of the pancreas (2); renal contusions (2); duodenal haematoma (1); and bowel perforation (3). In addition, there were three urethral injuries and five lacerations involving the abdominal wall and inguino-scrotal region. The presence of external bruising was a poor indicator of underlying brgan damage. Thirteen operations were performed and the mean hospital stay for the series was 9 days. CONCLUSIONS: Handlebar injuries are a significant cause of both blunt abdominal trauma and lacerations to the contact area. The infrequent finding of external bruising in the presence of major organ damage suggests that, although the velocity at impact may be relatively low, the small cross-sectional area of the end of the handlebar is a major factor contributing to organ damage. Moreover, we suspect that the high proportion of lacerations observed in this type of trauma result from the sharp metallic end of the handlebar cutting through the soft rubber handle. Manufacturers of bicycles should be made aware of these findings and should adjust the design of the handlebars accordingly.

Abdominal Injuries↗
PubMed1997

Rare pancreatic tumours in children (other than nesidioblastosis).

BACKGROUND: The rarity of pancreatic tumours other than nesidioblastosis in children is such that the experience of any one surgeon or institution is small. As a consequence, there is limited information on the appropriate management and outcome of these tumours. For this reason a review was conducted of the experience of a large paediatric surgical institution. METHODS: During a 23-year period, six patients with pancreatic tumours other than nesidioblastosis were treated at the Royal Children's Hospital, Melbourne. RESULTS: Despite the varied modes of presentation and surgery undertaken, all six patients with surgery alone, with follow-up from 1 to 18 years. Two of the tumours were malignant; the remaining four being islet cell adenomata. No form of adjuvant treatment (chemotherapy or radiotherapy) was used. CONCLUSION: These rare paediatric tumours appear to have a good prognosis, even when malignant, and respond well to radical surgical ablation. Adjuvant therapy appears to be unnecessary.

Adenoma, Islet Cell↗
PubMed1997

Bezoar formation and malabsorption secondary to persistent dilatation and dysmotility of the duodenum after repair of proximal jejunal atresia.

Bezoar formation is a rare but well-recognised complication of previous gastric surgery and persimmon ingestion. We present a case of bezoar formation in the duodenum of a child with a grossly dilated, dysmotile duodenum following surgery for jejunal atresia. The presenting symptoms were vomiting, diarrhoea, and growth failure, with evidence of malabsorption secondary to bacterial overgrowth in the bezoar. Plication of the duodenum to reduce its size and improve its motility may reduce the likelihood of future bezoar formation.

Bezoars↗
PubMed1996

A rare tumor masquerading as an empyema: pleuropulmonary blastoma.

Pleuropulmonary blastoma, although rare, should be considered in the differential diagnosis of children who present with a pleural effusion and symptoms of respiratory tract infection when the empyema fails to respond to medical management. A case of a 2-year-old boy with this rapidly growing tumor is reported. The treatment and outcome of pleuropulmonary blastoma in children is reviewed.

Antineoplastic Combined Chemotherapy Protocols↗