Search for lepton flavour violation in the eμ continuum with the ATLAS detector in [Formula: see text]pp collisions at the LHC

This paper presents a search for the t-channel exchange of an R-parity violating scalar top quark ([Formula: see text]) in the e±μ∓ continuum using 2.1 fb-1 of data collected by the ATLAS detector in [Formula: see text]pp collisions at the Large Hadron Collider. Data are found to be consistent with the expectation from the Standard Model backgrounds. Limits on R-parity-violating couplings at 95 % C.L. are calculated as a function of the scalar top mass ([Formula: see text]). The upper limits on the production cross section for pp→eμX, through the t-channel exchange of a scalar top quark, ranges from 170 fb for [Formula: see text] to 30 fb for [Formula: see text].

Measurement of the ZZ production cross section and limits on anomalous neutral triple gauge couplings in proton-proton collisions at sqrt[s] = 7 TeV with the ATLAS detector

A measurement of the ZZ production cross section in proton-proton collisions at sqrt[s] = 7 TeV using data corresponding to an integrated luminosity of 1.02 fb(-1) recorded by the ATLAS experiment at the LHC is presented. Twelve events containing two Z boson candidates decaying to electrons and/or muons are observed, with an expected background of 0.3 ± 0.3(stat)(-0.3)(+0.4)(syst) events. The cross section measured in a phase-space region with good detector acceptance and for dilepton masses within the range 66 to 116 GeV is σ(ZZ → ℓ+ ℓ- ℓ+ ℓ-)(fid) = 19.4(-5.2)(+6.3)(stat)(-0.7)(+0.9)(syst) ± 0.7(lumi) fb. The resulting total cross section for on-shell ZZ production, σ(ZZ)(tot) = 8.5(-2.3)(+2.7)(stat)(-0.3)(+0.4)(syst) ± 0.3(lumi) pb, is consistent with the standard model expectation of 6.5(-0.2)(+0.3) pb calculated at the next-to-leading order in QCD. Limits on anomalous neutral triple gauge boson couplings are derived.

Intraoperative stereotactic navigation for reconstruction in zygomatic-orbital trauma

Reconstruction of the maxillofacial skeleton after traumatic injury is not always straightforward because of its three dimensional complex anatomy and aesthetic signifi cance. In case of zygomaticorbital injury induced by trauma resulting in enophthalmos, the patient is affected on both function and cosmesis. To prevent diplopia or conspicuous asymmetry, exact correction of the orbital symmetry is required. The aim of this case report is to demonstrate the use of an intraoperative image guided navigation system for identifi cation of adequate reconstruction of the orbital fl oor and orbital symmetry in zygomatic-orbital fracture. Navigation-guided open reduction of a zygomatic-orbital complex fractures with orbital fl oor reconstruction can be regarded as a valuable treatment option for this potentially complicated procedure. This case demonstrated the use of the non-ionizing, noncontact, navigation system in intraoperative procedure and clinical monitoring to identify the correct position and symmetry in complex orbital fl oor reconstruction. Keywords: intraoperative navigations, orbital reconstruction, zygomatico-orbital fracture.

Intraoperative stereotactic navigation for reconstruction in zygomatic-orbital trauma

Reconstruction of the maxillofacial skeleton after traumatic injury is not always straightforward because of its three dimensional complex anatomy and aesthetic significance. In case of zygomatic-orbital injury induced by trauma resulting in enophthalmos, the patient is affected on both function and cosmesis. To prevent diplopia or conspicuous asymmetry, exact correction of the orbital symmetry is required. The aim of this case report is to demonstrate the use of an intraoperative image guided navigation system for identification of adequate reconstruction of the orbital floor and orbital symmetry in zygomatic-orbital fracture. Navigation-guided open reduction of a zygomatic-orbital complex fractures with orbital floor reconstruction can be regarded as a valuable treatment option for this potentially complicated procedure. This case demonstrated the use of the non-ionizing, noncontact, navigation system in intraoperative procedure and clinical monitoring to identify the correct position and symmetry in complex orbital floor reconstruction.

Anorectal malformations caused by defects in sonic hedgehog signaling

Anorectal malformations are a common clinical problem affecting the development of the distal hindgut in infants. The spectrum of anorectal malformations ranges from the mildly stenotic anus to imperforate anus with a fistula between the urinary and intestinal tracts to the most severe form, persistent cloaca. The etiology, embryology, and pathogenesis of anorectal malformations are poorly understood and controversial. Sonic hedgehog (Shh) is an endoderm-derived signaling molecule that induces mesodermal gene expression in the chick hindgut. However, the role of Shh signaling in mammalian hindgut development is unknown. Here, we show that mutant mice with various defects in the Shh signaling pathway exhibit a spectrum of distal hindgut defects mimicking human anorectal malformations. Shh null-mutant mice display persistent cloaca. Mutant mice lacking Gli2 or Gli3, two zinc finger transcription factors involved in Shh signaling, respectively, exhibit imperforate anus with recto-urethral fistula and anal stenosis. Furthermore, persistent cloaca is also observed in Gli2(-/-);Gli3(+/-), Gli2(+/-);Gli3(-/-), and Gli2(-/-);Gli3(-/-) mice demonstrating a gene dose-dependent effect. Therefore, Shh signaling is essential for normal development of the distal hindgut in mice and mutations affecting Shh signaling produce a spectrum of anorectal malformations that may reveal new insights into their human disease equivalents.

Video-assisted thoracoscopic thymectomy in juvenile myasthenia gravis

As video-assisted thoracoscopic surgery for thymectomy has been reported to be as effective as traditional open surgical approaches in predominantly adult patients with myasthenia gravis, we applied this procedure to juvenile patients with this condition. Six patients underwent total thymectomy using the video-assisted technique (1997-98). Six patients in whom a median transsternal approach was used (1989-95) formed the comparison group. The two patient groups were similar in terms of age at thymectomy and preoperative clinical severity. There were no serious perioperative complications in either group. Minimum post-thymectomy duration of follow-up in the video-assisted thoracoscopic surgery patients was 2.3 years (mean 2.7 years), with all patients clinically improved over their baseline status. Preliminary results suggest that video-assisted thymectomies are comparably effective to transsternal procedures in treating generalized juvenile myasthenia gravis and can be safely performed in children as young as 20 months of age. In addition, video-assisted surgeries are less invasive than transsternal approaches, significantly shorten the postoperative hospital stay, and have superior cosmetic results.

Directed blood donation in pediatric general surgery: Is it worth it?

PURPOSE

To date, there are no data to support the safety, efficacy, and cost-benefit ratio of donor-directed blood donation (DD). The objectives were to determine whether a DD program in pediatric general surgery practice is justified.

METHODS

A retrospective analysis was conducted of the transfusion practice and all DD requests received by transfusion services in a full calendar year (1997) at a tertiary care pediatric hospital. The authors examined the donations, utilization, and possible benefits for the recipients.

RESULTS

A total of 22,527 units of blood were transfused in 1997. General surgery used 471 (2%) of the total and 471 of 4,825 (10%) of all surgical transfusions. Total DD requests were 219 with only 11 of 219 (5%) originating from the general surgery department. After all the exclusions, 133 of 219 (61%) requests had DD blood available. DD blood had a higher true-positive rate for transmissible disease (1.1% v 0.10%), high-risk activity (2.5% v 1.2%), and malaria risk (3.1% v 0.31%). Total utilization of DD blood was 132 of 236 units (55.9%) and general surgery utilized 4 of 11 (36.4%) of their directed donations. Thirty-seven patients (27.8%) benefited from decreased donor exposure. No general surgery patient received more than 1 blood component to benefit from decreased donor exposure.

CONCLUSIONS

DD deferral rates are higher than for volunteer donors for infectious disease markers, malaria, and high-risk activities. There is no evidence that DD is safer than volunteer donation. DD blood wastage of 63.6% is much higher than in volunteer donation (7%). Thirty-seven patients (28%) received multiple units from one donor suggesting a benefit from decreased donor exposure. Given the low frequency of transfusion and the poor utilization of DD in general surgical practice, a DD program is not justified.

Acute chest syndrome after abdominal surgery in children with sickle cell disease: Is a laparoscopic approach better?

BACKGROUND/PURPOSE

Acute chest syndrome (ACS) is the leading cause of hospitalization and death among patients with sickle cell disease (SCD). Surgery is a risk factor for the development of ACS. It has been suggested that laparoscopic surgery could diminish the risk of sickle-related complications; therefore, more procedures may be encouraged in asymptomatic patients. The goal of the authors was to determine the incidence of postoperative ACS and assess for predisposing factors in all sickle cell patients undergoing abdominal surgery.

METHODS

A retrospective analysis of all sickle cell patients receiving abdominal surgery (open and laparoscopic) between 1994 and 1998 was conducted. Data pertaining to demographics, perioperative clinical status, postoperative care, and outcome were collected and analyzed using Student's t test or chi(2) where appropriate.

RESULTS

Fifty-four children underwent 62 procedures (35 abdominal and 27 extracavitary). All abdominal cases were either cholecystectomy or splenectomy (22 laparoscopic and 13 open). ACS occurred in 7 of 62 (11.3%) overall, and all were in abdominal cases 7 of 35 (20%). ACS occurred in 5 of 22 (22.7%) laparoscopic cases and 2 of 13 (15.4%) open cases. Operating time was significantly longer in the laparoscopic group compared with open cases (P <.05). A higher percentage of patients who had ACS had at least 1 previous episode (71.4% v 39.3%; P value not significant) and a smaller percentage of ACS patients received a preoperative blood transfusion (14.3% v 32.1%; P value not significant). Postoperative hospitalization was prolonged if ACS occurred (9 +/- 2 v 3 +/- 2 days; P <.05).

CONCLUSIONS

Abdominal surgery carries a significantly high risk (20%) of ACS. Laparoscopy does not decrease the incidence of ACS compared with open approach. Predisposing factors were not significant in predicting postoperative ACS. There is considerable morbidity and potential cost implications in patients with ACS.

Long-term outcome after nonoperative management of complete traumatic pancreatic transection in children

PURPOSE

The treatment of complete pancreatic transection (CPT) from blunt trauma remains controversial. To determine the natural history and long-term outcome of nonoperative management of CPT, we analyzed all such patients over the last 10 years at a level I trauma center.

METHODS

Retrospective analysis between 1990 and 1999 was performed on 10 consecutive patients. Complete records were available for 9 patients. Data pertaining to their trauma admission, plus long-term radiologic and clinical outcome were analyzed.

RESULTS

There were 6 boys and 3 girls with a median age of 8 years (range, 4 to 16 years) and a median injury severity score (ISS) of 25. All patients displayed CPT on admission computed tomography (CT) scan. Four patients (44%) had associated intraabdominal injuries, but only 2 were significant. All patients were treated nonoperatively. Four patients (44%) had pseudocysts, and 3 required percutaneous drainage. Other complications included a single drainage of subphrenic collection, 1 inadvertent removal of drainage catheter, and 2 cases of line sepsis. The duration of percutaneous drainage was 14 to 60 days. The median length of hospitalization was 24 days (range, 6 to 52 days). After median follow up of 47 months, no patients showed exocrine or endocrine insufficiency. One patient had abdominal pain not related to the pancreatic injury. Follow-up abdominal CT scans in 8 of 9 patients showed complete atrophy of the body and tail in 6 patients and 2 completely normal glands.

CONCLUSIONS

Pancreatic transection is rare and commonly is found in isolation of other major abdominal injuries. No patients required surgery for their pancreatic transection. Pseudocysts can be managed effectively with percutaneous drainage. After a median follow-up of 47 months, no patients had endocrine or exocrine dysfunction. Anatomically, the distal body and tail usually atrophies; however, occasionally, the gland can heal and appear to recanalize. To the authors' knowledge, this is the first report to show the effectiveness of nonoperative management after complete pancreatic transection.

Murine models of VACTERL syndrome: Role of sonic hedgehog signaling pathway

BACKGROUND/PURPOSE

VACTERL syndrome is a common surgical condition affecting the development of many midaxial organs. The etiology, embryology, and pathogenesis of the VACTERL syndrome are not known. The authors report here new mouse models of VACTERL syndrome involving the Sonic hedgehog (Shh) signaling pathway.

METHODS

Mutant mice involving Shh signaling, the Shh transcription factors Gli2-/- and Gli3-/-, Gli2-/-;Gli3+/- double heterozygotes, and Shh-/- were analyzed.

RESULTS

In addition to reported vertebral, anal, tracheoesophageal, and limb anomalies, mutant mice display cardiac, renal, and associated anomalies, namely congenital diaphragmatic hernia and omphalocele, known to be associated in VACTERL syndrome. The Shh transcription factors Gli2 and Gli3 have specific and overlapping roles in the induction of VACTERL phenotypes in a gene-dose dependent manner in these mutants.

CONCLUSION

To the authors' knowledge, these mutant mice represent the first animal model that mimics the human VACTERL syndrome, and suggests that aberrations in Shh signaling might be involved in the VACTERL syndrome.

The management of nonpigmented gallstones in children

BACKGROUND/PURPOSE

An increasing number of children are diagnosed with gallstones today. The best management of nonpigmented gallstones in children without hematologic disorders is not known.

METHODS

The authors prospectively studied 74 children with cholelithiasis diagnosed with ultrasonography. Clinical presentation, natural history, complications, and indications for cholecystectomy were examined. The follow-up (mean, 21 months) consisted of routine clinic visits, chart reviews, and telephone questionnaires with the children or their parents.

RESULTS

Of the 74 children, 33 required cholecystectomies, and 41 were followed. The average age was similar in the 2 groups (11.7 v 11.0 years). Children with risk factors for cholelithiasis required earlier surgical treatment (P < .001). In the operative group, 8 presented acutely and 25 electively. There were 2 complications, a wound infection and a retained common duct stone. In the group that underwent follow-up, 34 of 41 children remained asymptomatic or had symptoms improve with dietary manipulation. No complications developed during the follow-up period.

CONCLUSIONS

Children with gallstones and typical symptoms of right upper quadrant or epigastric pain with food intolerance should undergo cholecystectomy. Eighty-two percent of children with cholelithiasis and atypical symptoms had improvement with dietary manipulation. Pediatric patients with gallstones that are asymptomatic or associated with atypical symptoms can be safely followed without complications.

The late nonfunctioning duodenal atresia repair--a second look

BACKGROUND/PURPOSE

In 1986, the authors reported on 3 newborns who had repair of their duodenal atresia, and between 6 and 18 months postoperatively an anastomotic obstruction developed in each suddenly. After prolonged medical and surgical treatments it became apparent that the duodenal atresia repair was functionally obstructed and plication of the dilated atonic proximal duodenum was curative. Since then, 2 more patients became so obstructed at 5 and 24 years postoperatively. The aim of this study was to report the very late occurrence of a functional obstruction of a newborn duodenal atresia repair.

METHODS

The 2 additional histories and surgical repairs were reviewed.

RESULTS

The 5-year old boy was cured immediately with plication only of his dilated proximal duodenum. The 24-year-old nurse had a very stormy 2-year course with several bypass operations, which did not relieve her abdominal pain and bile vomiting until they were taken down and her dilated proximal duodenum was plicated, after which she made a good recovery. Both remain well.

CONCLUSION

An uncommon, very late, sudden, apparently anastomotic, postoperative, newborn, duodenal atresia repair obstruction caused by proximal, dilated, duodenal atony, and dysfunction can occur many years later and responds to duodenal plication alone.

Near-total intestinal aganglionosis: long-term follow-up of a morbid condition

PURPOSE

The aim of this study was to understand the long-term outcome of near-total intestinal aganglionosis (NTIA).

METHODS

The study was an institutional review of all patients with NTIA between 1974 and 1999, inc!usive. Seven full-term babies were identified (4 boys, 3 girls). Mean birth weight was 3.2 kg (range, 2.7 to 4.1). Patients included 1 pair of siblings and 1 Down's syndrome baby. All 7 had obstruction within 5 days of life. One patient experienced bowel perforation. All 7 had NTIA diagnosed within the first 2 months of life. In 2 of 7, aganglionosis began 10 cm distal to the ligament of Treitz (LOT). The longest segment of normal small bowel was 130 cm from the LOT. Five of 7 babies underwent a stoma between day of life (DOL) 1 and 15.

RESULTS

Two of three "long-term" survivors (>2 years) had corrective surgery by 13 months. The first received extended jejuno-ileal myotomy and myectomy with multiple postoperative problems. She died at 8 years of age of complications of total parenteral nutrition (TPN). The second underwent myotomy, resection and patch graft to jejunum, and several jejunostomy revisions. All of the involved bowel eventually was resected. The 3 of 7 who lived more than 1 year all took some nutrition orally. Three died, between 3 months and 8 years of age, of complications of TPN. There are 2 survivors at 3 and 7 years of age. Survival has not correlated with the length of aganglionic bowel.

CONCLUSIONS

Aganglionosis involving most of the bowel has a high morbidity and mortality rate. Since 1990 a more aggressive surgical approach has resulted in improved survival rates but with significant morbidity. For children surviving beyond 3 months of age, outcome was less dismal. Some patients may benefit from extended jejunal myotomy or myectomy. However, postoperative complications are the rule, not the exception.

Thoracoscopic thymectomy in juvenile myasthenia gravis

BACKGROUND

Although transsternal thymectomy is an effective method in the treatment of juvenile myasthenia gravis (JMG) it is traumatic in pediatric patients. Thoracoscopic thymectomy offers an effective and less traumatic approach with respect to cosmesis and postoperative recovery.

METHODS

A retrospective analysis of 6 consecutive patients treated with thoracoscopic thymectomy was performed. Perioperative parameters and cost analysis were compared with those of 6 consecutive open procedures performed before the study.

RESULTS

Thoracoscopic thymectomy can be performed in patients as young as 1.6 years. There was no conversion to open procedure and no perioperative morbidity and mortality. The length of operating time and the surgical cost of thoracoscopic procedure were not significantly different from those of open procedure. The length of hospitalization, however, was significantly shorter with thoracoscopic procedure, and hence the overall cost was significantly reduced (P < .05). An intermediate follow-up shows that outcome after thoracoscopic procedure is equally as effective as open procedure.

CONCLUSIONS

Thoracoscopic thymectomy offers an equally effective but cosmetically more acceptable approach than sternotomy. It has a quicker recovery period and appears to be a less costly alternative to transsternal thymectomy.

Murine xenogeneic immune responses to the human testis: a presumed immune-privileged tissue

INTRODUCTION

Immune privilege provides a natural paradigm for potentially down-regulating allogeneic and xenogeneic inflammatory immune responses. Fas ligand has been suggested as a general underlying mechanism of immune privilege; the human Fas ligand has been shown to ligate murine Fas in vitro.

METHODS

In this study, we examined whether the human testicular xenograft, a presumed immune-privileged tissue would have prolonged survival in mice. In addition, in vitro and in vivo murine xenogeneic immune responses to the human testicular xenografts were characterized using MHC class I, MHC class II, CD4, CD8, CD4/8 knockout mice.

RESULTS

Unlike in rodent testis, Fas ligand mRNA is not expressed and Fas is highly expressed in human testis. Human testicular xenografts are immunogenic, and do not induce any preferential pattern of recipient systemic Th1 or Th2 cytokine bias. Interestingly, an indefinite survival of the human testicular xenografts is observed in murine MHC class II knockout mice, whereas the human skin xenografts were rejected without a delay. In vivo murine immune responses to human testicular xenografts require a recipient MHC class II-dependent CD4 T cell-mediated process that appears to depend on B7-1/B7-2 costimulatory signals.

CONCLUSIONS

Our results demonstrate that the concept of immune privilege, as defined by the expression of Fas ligand and prolonged survival after transplantation, cannot be extended to human testis. The stringent restriction of murine xenogeneic immune responses to discordant human testicular xenografts to the indirect MHC class II-dependent CD4 T cell-mediated pathway suggests a potential venue for immune modulation to induce tolerance across a discordant species barrier.

New mouse models of congenital anorectal malformations

BACKGROUND/PURPOSE

The genetic, embryological, and pathogenetic aspects of hindgut development remain poorly understood. Recently, the morphogenetic pathway involving the Sonic hedgehog (Shh) gene has been shown essential to the normal development of many midaxial organs, including the foregut. This study reports genetically based murine models of congenital anorectal malformations (CAM) involving the Shh-responsive transcription factors, Gli2 and Gli3. Its purpose is to show the necessity of these 2 factors to normal hindgut development.

METHODS

Gli2-/- mutants were generated by a targeted deletion. Gli3-/- mutants are spontaneous mutants involving the Gli3 gene. Gli2-/- Gli3+/- mutants were generated by intercrossing double heterozygotes. Whole-mount midsagittal sections of the embryos were analyzed on embryonic days (E) 11.5 and E13.5.

RESULTS

Gli3-/- mutants had anal stenosis and ectopic anus, and Gli2-/- mutants showed imperforate anus and rectourethral fistula. Gli2-/- Gli3+/- mutants had a cloacal abnormality.

CONCLUSIONS

The phenotypic abnormalities observed in these mutant mice are identical to the spectrum of human CAM. The severity of the phenotype appears to reflect the gene dose. Gli2 and Gli3 play an important role in the normal development of murine hindgut. The results of this study provide, for the first time, a molecular basis for CAM.

T cells are necessary and critical for xenograft rejection in new concordant cardiac xenotransplant model

BACKGROUND

A new vascularized concordant xenotransplant model using the Chinese hamster as donor and mouse as recipient species is reported. This model takes advantage of the wealth of informative immune reagents and knockout and transgenic backgrounds available for the mouse.

METHODS

Heterotopic auxillary cardiac transplantation was performed. The mean survival time was assessed by daily palpation. Xenoreactive antibody production was measured by flow cytometry, and cardiac xenografts were examined by light microscopy.

RESULTS

The tempo of xenograft rejection in this model is consistent with concordant species combination. IgM and IgG3 responses were not critical for the concordant xenograft rejection. Long-term survival (>100 days) of the concordant cardiac xenografts was observed without any immunosuppression in nude mice. Reconstitution of nude mice with CD3+ T cells induced the xenograft rejection in 5.7 days (P<0.01).

CONCLUSION

This new concordant cardiac xenotransplant model demonstrates that T-dependent xenogeneic immune response is necessary and critical for the xenograft rejection.

Long-term morbidity in total colonic aganglionosis

BACKGROUND/PURPOSE

No surgical treatment for total colonic aganglionosis (TCA) clearly has been proven superior. To identify clinical criteria associated with long-term functional outcome, a 28-year retrospective institutional review of this entity from 1969 through 1996 inclusive was undertaken.

METHODS

Total colonic aganglionosis (TCA), defined here as aganglionosis extending from the anus to at least the ileocecal valve but no further than 50 cm proximal to the ileocecal valve, was identified in 29 infants and children. Appropriate leveling ileostomy was performed in 28 of 29 patients, and definitive surgical reconstruction was performed in 26 of 29. Three groups were identified based on the definitive surgical repair performed: group 1, construction lacking or incorporating a short ganglionic-aganglionic common channel (modified Soave or modified Duhamel, n = 8); group II, construction of an extended common channel (Martin-Duhamel, Martin-Soave; n = 6); and group III, all others including an intermediate-length common channel (n = 13).

RESULTS

Functional outcome at extended follow-up (mean, 6.6 +/- 5.6 years; range, 0.7 to 23) was determined based on survival, long-term ostomy requirements, growth, major complications, continence, and enterocolitis and bowel movement frequency. Although long-term functional outcome was deemed satisfactory in six of seven patients in group I, function was satisfactory in none of six group II patients. Group III results were intermediate (satisfactory in 6 of 13).

CONCLUSIONS

Acceptable long-term outcome was most frequent in TCA patients whose definitive repair did not incorporate an extended ganglionic-aganglionic common channel. The use of extensive lengths of aganglionic bowel to maximize fluid absorption is frequently met with substantial morbidity.

Molecular evolution of P transposable elements in the genus Drosophila. III. The melanogaster species group

Phylogenetic relationships were determined for 76 partial P-element sequences from 14 species of the melanogaster species group within the Drosophila subgenus Sophophora. These results are examined in the context of the phylogeny of the species from which the sequences were isolated. Sequences from the P-element family fall into distinct subfamilies, or clades, which are often characteristic for particular species subgroups. When examined locally among closely related species, the evolution of P elements is characterized by vertical transmission, whereby the P-element phylogeny traces the species phylogeny. On a broader scale, however, the P-element phylogeny is not congruent with the species phylogeny. One feature of P-element evolution in the melanogaster group is the presence of more than one P-element subfamily, differing by as much as 36%, in the genomes of some species. Thus, P elements from several individual species are not monophyletic, and a likely explanation for the incongruence between P-element and species phylogenies is provided by the comparison of paralogous sequences. In certain instances, horizontal transfer seems to be a valid alternative explanation for lack of congruence between species and P-element phylogenies. The canonical P-element subfamily, which represents the active, autonomous transposable element, is restricted to D. melanogaster. Thus, its origin clearly lies outside of the melanogaster species group, consistent with the earlier conclusion of recent horizontal transfer.

Management of gastroschisis with concomitant jejuno-ileal atresia

BACKGROUND

The incidence of jejuno-ileal atresia in neonates concomitantly found to possess gastroschisis has been reported to be 5% to 25%. Initial treatment for this condition has not been well established.

METHODS

Thirteen newborns with gastroschisis and coexisting jejuno-ileal atresia, were identified and treated at our institution over the past 16 years (1978 through 1996). Patient characteristics at presentation, surgical therapy, and complications at extended follow-up were reviewed.

RESULTS

All neonates were preterm (mean gestational age, 35.2 +/- 2.0 weeks) and of low birth weight (2.1 +/- 0.4 kg). Atresia types II, IIIa, IIIb, and IV were identified at the initial surgical procedure in one, eight, one, and three patients respectively; however, one synchronous small bowel atresia went unrecognized. A primary anastomosis was fashioned in 8 of 13 newborns, the creation of which did not influence length of hospitalization, length of total parenteral nutrition (TPN) requirement, complication rate, or survival; however, reoperation was required in two of eight patients to mediate anastomotic complications. Atresia associated with intestinal gangrene or perforation was treated by primary anastomosis in three of six patients and the remaining three by enterostomy. Primary abdominal wall closure was possible in 10 of 13 patients; a Silon pouch was required in three. All nine survivors (69%) displayed protracted small bowel dysfunction requiring TPN (mean TPN duration of 3.6 +/- 3.0 months; range, 1 to 11). Mortality in four patients was a consequence of severe prematurity, Silon pouch wound sepsis, or TPN-induced cirrhosis.

CONCLUSIONS

When technically feasible, restoration of intestinal continuity by primary anastomosis is a reasonable treatment option in patients with coexisting gastroschisis and jejuno-ileal atresia. Favorable outcome is as much a function of supportive care and parenteral nutrition as the type of surgical repair performed for either the intestinal or the abdominal wall defect.

Tobogganing injuries in children

AIM

To undertake a retrospective review of tobogganing-related injuries in children requiring admission to the Hospital for Sick Children, Toronto.

MATERIALS AND METHODS

Twenty-two children with tobogganing-related injuries were admitted between December 1991 and December 1993. There were 13 boys and 9 girls (median age, 10 years; range, 3 to 17 years). Their charts were reviewed using a structured proforma.

RESULTS

Nine patients (41%) sustained injuries by striking a tree, 8 struck other objects, and 5 fell from the toboggan. Only 1 was wearing protective headgear. The initial site of impact was the head in 13 patients (59%), the trunk in 5, and the extremities in 4. Major injuries were sustained in all body systems. Thirteen patients (59%) required surgical treatment and two patients died, one of cerebral edema and the other of acute renal failure and subsequent multiorgan failure.

CONCLUSION

Tobogganing-related injuries represent a small fraction of all injuries in children who require hospitalization. However, such injuries can be serious and can cause significant morbidity and mortality. Better public awareness of the risks of tobogganing is required and simple safety guidelines should be developed to reduce the risks of this popular winter pastime.

Colonic atresia combined with Hirschsprung's disease: a diagnostic and therapeutic challenge

Three new cases of patients with co-occurrence of colonic atresia and Hirschsprung's disease and a review of the literature (n = 5) are presented in this report. All patients (n = 8) except one were full-term infants who had no other significant anomalies. The preterm infant had associated tetralogy of Fallot in addition to Hirschsprung's disease and colonic atresia. Six patients had atresia of the ascending colon, and two had atresia of the colon to splenic flexure. All colonic atresias were diagnosed neonatally; however, there was mean delay of 15.4 months (range, 1 mo to 5 years) in diagnosing associated Hirschsprung's disease. There were two deaths. A careful examination of the resected specimen to rule out Hirschsprung's disease is recommended. Performing a rectal biopsy must be considered for patients who initially were treated for colonic atresia and who have a slow return of normal gut function.

Laparoscopic cholecystectomy versus open cholecystectomy in children: which is better?

Twenty-nine consecutive laparoscopic cholecystectomies (LC) performed between April 1992 and December 1993 were compared with 23 consecutive open cholecystectomies (OC) performed between January 1991 and March 1992 with regard to clinical, surgical, and economic factors. Most patients were Caucasian (> 70%), and symptomatic nonhemolytic cholelithiasis was the most common indication for cholecystectomy. The introduction of LC did not significantly increase the number of cholecystectomies performed per annum. There is a learning curve to LC: the average length of operative time required during the first year was significantly longer than that of OC and the average time for LC during the second year (P < .01). By the second year, the average operative time of LC was not significantly different from OC. There was no conversion from LC to OC, and the complication rate was minor in both groups. The postoperative parenteral analgesic requirement for LC was significantly less than OC (P < .01). The mean length of hospitalization of LC was about three times shorter than that of OC (P < .01). Although the average operating cost per case of LC was significantly more expensive than OC, LC was significantly cheaper because the period of hospitalization was significantly shortened (P < .01). In conclusion, LC is the procedure of choice in the treatment of symptomatic cholelithiasis in children.

Unusual isolated common bile duct injury after blunt trauma

Isolated injury to the extrahepatic biliary tree after blunt trauma is rare. The authors describe the case of a 17-year-old boy who suffered such an injury after falling over the handlebar of his motorcycle. Ultrasonography, computed tomography and abdominal paracentesis were used to make the diagnosis. At laparotomy there was a partial tear of the common bile duct at its junction with the cystic duct. A cholecystectomy was performed and a T tube inserted. The patient recovered without complication. The authors emphasize that only awareness of the condition and diagnostic confirmation by computed tomography and abdominal paracentesis can expedite the diagnosis and treatment. The choice of surgical repair must be individualized according to the clinical findings and the nature of the injury.