Validity of a three-dimensional public-domain system for contemporary endodontic research

The purpose of this study was to evaluate the limits and benefits of a visualization system based on public-domain software for contemporary three-dimensional (3-D) endodontic research purposes. Three-dimensional bio-models of six human teeth and of one bone-implant specimen were generated using cross-sectional imaging. To evaluate the overall performance in processing large data sets and in reproducing accurate 3-D morphology, slices with a thickness varying from 100 microm to 10 microm were cut. Auto-outlining and segmenting techniques were tested. The 3-D bio-models represented in accurate detail the different morphological aspects of the specimen. Voxel volumes of 0.116 x 10(-5) mm3 could be realized and were only restricted by the computer hardware limitations. The system is not limited to dental hard tissues. Hypomineralized material and soft tissues as well as bone- and allogeneic-implant material could be visualized. The method presented is valid and meets current requirements applying to endodontic research. The broad-based use of high-quality, public-domain software and the resulting exchange of experience help to manage resources and may contribute to enhancing the in-process quality of research.     

Arterial switch operation with a single coronary artery

OBJECTIVE: Our purpose was to evaluate the impact of coronary pattern on survival and reintervention in patients who underwent the arterial switch operation with a single coronary artery. METHODS: We conducted a retrospective analysis of 53 patients with a single coronary artery who underwent the arterial switch operation between 1983 and 2000 at Children's Hospital Boston. Recent follow-up information was obtained for 40 of the 46 long-term survivors (mean follow-up 7.3 +/- 4.5 years). RESULTS: Thirty-five patients had a single right coronary artery, with the left coronary artery posterior to the pulmonary artery in 27. Eighteen patients had a single left coronary artery (16 with the right coronary artery anterior to the aorta). Six of 7 total patients who died had a single right coronary artery; all died before 1992. There were 5 early deaths, all with a single right coronary artery, with 4 deaths due to coronary malperfusion. Survivals for all patients were 91% at 6 months and 87% at 1, 5, and 10 years after the arterial switch operation. Survival figures were lower for patients having a single right ostium with the left main coronary artery posterior to the pulmonary artery compared with all other subtypes (P =.02, log-rank test). Seven patients had reintervention, 4 because of right ventricular outflow tract obstruction, 1 for heart transplantation, 1 for mitral valve repair and 1 for pacemaker implantation. Freedom from reintervention for all patients was 96% at 6 months, 92% at 1 year, 86% at 5 years, and 82% at 10 years after the arterial switch operation, with lower rates for patients having a single left ostium with the right coronary artery anterior to the aorta (P =.0003, log-rank test). CONCLUSIONS: In the current era, the arterial switch operation with a single coronary artery can be performed safely irrespective of the coronary anatomy. Risk of reintervention is higher in patients having a single left ostium with the right coronary artery anterior to the aorta.     

Improving results of the modified Fontan operation in patients with heterotaxy syndrome

BACKGROUND: Historically the Fontan operation in patients with single ventricle heterotaxy syndrome and atrial isomerism has been associated with high mortality. We studied whether recent modifications of the surgical technique have improved outcome. METHODS: A retrospective review of 135 patients with heterotaxy syndrome who underwent a Fontan operation between 1981 and 2000 was performed. RESULTS: There were 93 patients with right isomerism and 42 with left isomerism. Anomalies of venous return included 25 patients with extracardiac pulmonary venous connection (19%) and 37 patients with an interrupted inferior vena cava (27%). Thirty-six patients (27%) had at least moderate atrioventricular valve regurgitation. The type of Fontan procedure included 17 patients with an atriopulmonary Fontan connection, 67 with a lateral tunnel modification, 19 with an intraatrial tube graft, 25 with an extracardiac tubegraft, and 7 with an intra-extra atrial tube graft. A fenestration was placed in 93 patients (78%). Early mortality was 19% before 1991, 3% since 1991, and no patient has died early since 1993. Ten-year survivals were 70% for Fontan operations before 1990 and 93% for Fontan operations after 1990. Thirty-two patients (23%) had prolonged pleural effusions. Risk factors for death included anomalous pulmonary venous connection (p = 0.02) and higher preoperative pulmonary vascular resistance (p = 0.002). Sixty-two patients (47%) had some form of early postoperative arrhythmia. At 10 years, freedom from late bradyarrhythmia and late tachyarrhythmia were 78% and 70%, respectively. Preoperative arrhythmias, older age at operation, and anatomic features were each independent predictors of late arrhythmia. CONCLUSIONS: The Fontan operation can now be performed in patients with heterotaxy syndrome with excellent survival. However, morbidity in terms of postoperative arrhythmias and prolonged pleural effusions remains significant. Fontan staging, appropriate choice of Fontan modification, aggressive treatment of concomitant malformations, and use of a baffle fenestration contribute to improved outcome.     

移植肾功能延迟恢复的护理体会

1临床资料我院1997-11/2004-11共行肾移植562(男386,女176)例,期中87例患者出现移植肾功能延迟恢复(DGF),男性58例,女性29例,年龄16～62(平均38.5)岁.术后常规服免疫抑制剂:环孢素,强的松,骁悉.发生DGF最早术后第4日,最晚20 d,均采用综合治疗措施,纠正水、电解质紊乱,控制血压,预防感染等,同时对不同原因引起的DGF采用相应的治疗、护理.85例患者均在术后3wk左右肾功能恢复,2例因并发症死亡.     

Long-term results of the lateral tunnel Fontan operation

OBJECTIVES: Completion of a total cavopulmonary anastomosis with an intra-atrial lateral tunnel is known to yield good early and midterm results. In this study, we sought to determine the long-term outcome (10 years) after a lateral tunnel Fontan procedure. METHODS: Between October 1987 and December 1991, 220 patients (aged 11 months to 32 years) with a wide range of underlying diagnoses underwent a fenestrated or nonfenestrated lateral tunnel Fontan procedure at our institution. Current follow-up information was available for 196 patients (94%, mean follow-up = 10.2 +/- 0.6 years). Risk factor analysis included patient-related and procedure-related variables, with death, failure, and bradyarrhythmia or tachyarrhythmia as outcome parameters. RESULTS: There were 12 early deaths (<30 days or hospital death), 7 late deaths, 4 successful takedown operations, and 4 heart transplantations. Kaplan-Meier estimated survival was 93% at 5 years and 91% at 10 years, and freedom from failure was 90% at 5 years and 87% at 10 years. Freedom from new supraventricular tachyarrhythmia was 96% at 5 years and 91% at 10 years; freedom from new bradyarrhythmia was 88% at 5 years and 79% at 10 years. Three patients had evidence of protein-losing enteropathy. Multivariable risk factors for development of supraventricular tachyarrhythmia included heterotaxy syndrome, atrioventricular valve abnormalities, and preoperative bradyarrhythmia. Risk factors for bradyarrhythmia included systemic venous anomalies. The sole risk factor for late failure was a previous coarctation repair. CONCLUSION: The lateral tunnel Fontan procedure results in excellent long-term outcome even when used in patients with diverse anatomic diagnoses. The incidence of atrial tachyarrhythmia is low and mainly depends on the underlying cardiac morphology and preoperative arrhythmia. The good long-term outcome after an intracardiac lateral tunnel Fontan procedure should serve as a basis for comparison with other surgical alternatives.     

Metabolic effects of growth hormone treatment: an early predictor of growth response?

Fourteen children receiving one year of recombinant human growth hormone (rhGH) treatment underwent measurement of serial changes in body composition (measured by skinfold thickness, bioelectrical impedance, and H2(18)O dilution), resting energy expenditure (REE, estimated by ventilated hood indirect calorimetry), and total free living daily energy expenditure (TEE, measured by the doubly labelled water technique). Mean height velocity increased from 4.9 to 8.6 cm/year after six months of treatment. Fat free mass (FFM) increased more during the first six weeks (24.4 g/day) than from six to 26 weeks of treatment (6.8 g/day); fat mass decreased by 7.2 g/day and 1.1 g/day respectively. The six week increase in REE (kJ/day) was maintained after six months of treatment, though expressed per kilogram FFM (kJ/kgFFM/day), returned to pretreatment values by three months. Height velocity increases at six months correlated with six week changes in fat mass measured by skinfold thickness and REE, though use of this relationship to predict growth response in individuals is limited by the wide 95% prediction intervals. No significant changes in growth, body composition, or energy expenditure were observed between six and 12 months of treatment, in either patients who had initially responded well to treatment or those who were poor initial responders to treatment and who had their dose of rhGH doubled after six months.     

Outcome of cadaver kidney transplantation in small children

Cochat P, Castelo F, Glastre C, Martin X, Stamm D, Long D, Lavocat M-P, Hadj-Aïssa A, Lyonnet D, Floret D. Outcome of cadaver kidney transplantation in small children. Acta Pædiatr 1994;83:78–83. Stockholm. ISSN 0803–5253 Small children have often been reported to have poor outcome after kidney transplantation (KT). Recent reports from North America have shown that the use of living-related donors improves patient and graft survival. We report the experience in one centre of primary cadaveric KT using sequential immunosuppression in nine children aged 8–30 months and weighing 5.4–9.8 kg; donors were 0.7–12.3 years old. Four patients had pre-emptive KT and the other five were on peritoneal dialysis; the mean ± SD waiting time was 2.0 ± 2.4 months. Perioperative care has been published previously. The surgical approach was intraperitoneal if the aorta and vena cava were used (n= 7) and extraperitoneal for common iliac vessels anastomosis (n = 2); the duration of surgery was 3.5 ± 0.9 h and the time for vascular anastomosis was 32 ± 6 min. The recipients received ATG, azathioprine, prednisone and delayed administration of cyclosporin A. The patients were followed for 12–98 (median 41) months and showed good graft function (inulin clearance 63–100 ml/min/1.73 m²); only one child with recurrent haemolytic uraemic syndrome lost his graft three months post-transplantation and died after he had received a second graft. None of the recipients required post-transplant dialysis; arterial hypertension involved four children and was related to graft artery stenosis in two. Growth improved by 0.24 ± 0.48 SD score of height per year. Compared to earlier reports on cadaver transplantation in small children (about 40% graft survival after five years) and to the outcome of chronic peritoneal dialysis, the present results are better and appear to be similar to those obtained with living-related donor transplantation.