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排序方式: 共有138条查询结果,搜索用时 31 毫秒
1.
Results of the Ross operation in a pediatric population   总被引:1,自引:0,他引:1  
Objective: To analyse the results of the mid-term clinical and echocardiographic follow-up of the pediatric Ross operation. Methods: Echo-Doppler follow-up of 53 consecutive pediatric Ross procedures performed between 1994 and 2003. Median age was 9.7 years at time of operation (2 weeks–17.7 years). Six patients were younger than 3 months. Median age at follow-up was 15.6 years. Aortic valve/left ventricular outflow tract (LVOT) anomalies were congenital in 49 (92%). Seventy percent had previous surgery or balloon valvuloplasty. Root replacement was used in all. Thirteen patients (25%) had LVOT enlargement. Mean cross-clamp time was 113 (69–189) minutes. Results: Early mortality occurred in 3 patients after emergency surgery following balloon failure (n=1) and extended Ross following interrupted arch/VSD repair (n=2). Late mortality was due to LV fibroelastosis in 2 patients and complicated pulmonary artery stenting in another. RVOT reoperations were required because of late homograft obstruction in 2 patients and because of pulmonary artery stenosis in another. Five patients (9.4%) were reoperated for pulmonary autograft dilatation (n=3) and for leaflet fibrosis or perforation (n=2). Autografts were repaired in two patients, while a mechanical valve was inserted in 3 cases. At 9 years the actuarial survival and event free survival were 89 and 74%, respectively. At last follow-up 90% of autograft diameters indexed to body surface area was above the 90th percentile of normal aortic root diameters. LVOT and RVOT gradients were low and autograft insufficiency was trivial to mild in 84% and mild to moderate in 16%. Autograft stenosis was not noticed. Conclusions: The pediatric Ross procedure remains an important tool but autograft dilatation also occurs in the pediatric population. The significance of this finding has yet to be determined.  相似文献   
2.
Objective To describe the different imaging modalities used for the diagnosis and classification of hydrocephalus, their role in defining the optimal treatment of hydrocephalus and to define the optimal preoperative diagnostics for endoscopic third ventriculocisternostomy (ETV). Methods An overview on available imaging modalities for hydrocephalus will be given and their pros and cons discussed. In addition, different aspects of the treatment of hydrocephalus by shunts and by ETV will be highlighted. Discussion The role of the technical aspects of performing an ETV, the role of the surgeon’s philosophy, the role of the urgency of the procedure, and the role of informed consent on the requirements for the imaging of the hydrocephalus will be discussed. Conclusion The authors conclude that MRI is a conditio sine qua non for ETV in elective surgical cases.  相似文献   
3.
Introduction and objectivesThe goals of transurethral resection of a bladder tumor (TUR) are to completely resect the lesions and to make a correct diagnosis in order to adequately stage the patient. It is well known that the presence of detrusor muscle in the specimen is a prerequisite to minimize the risk of under staging.Persistent disease after resection of bladder tumors is not uncommon and is the reason why the European Guidelines recommended a re-TUR for all T1 tumors. It was recently published that when there is muscle in the specimen, re-TUR does not influence progression or cancer specific survival.We present here the patient and tumor factors that may influence the presence of residual disease at re-TUR.Material and methodsIn our retrospective cohort of 2451 primary T1G3 patients initially treated with BCG, pathology results for 934 patients (38.1%) who underwent re-TUR are available. 74% had multifocal tumors, 20% of tumors were more than 3 cm in diameter and 26% had concomitant CIS.In this subgroup of patients who underwent re-TUR, there was no residual disease in 267 patients (29%) and residual disease in 667 patients (71%): Ta in 378 (40%) and T1 in 289 (31%) patients. Age, gender, tumor status (primary/recurrent), previous intravesical therapy, tumor size, tumor multi-focality, presence of concomitant CIS, and muscle in the specimen were analyzed in order to evaluate risk factors of residual disease at re-TUR, both in univariate analyses and multivariate logistic regressions.ResultsThe following were not risk factors for residual disease: age, gender, tumor status and previous intravesical chemotherapy. The following were univariate risk factors for presence of residual disease: no muscle in TUR, multiple tumors, tumors > 3 cm, and presence of concomitant CIS. Due to the correlation between tumor multi-focality and tumor size, the multivariate model retained either the number of tumors or the tumor diameter (but not both), p < 0.001. The presence of muscle in the specimen was no longer significant, while the presence of CIS only remained significant in the model with tumor size, p < 0.001.ConclusionsThe most significant factors for a higher risk of residual disease at re-TUR in T1G3 patients are multifocal tumors and tumors more than 3 cm. Patients with concomitant CIS and those without muscle in the specimen also have a higher risk of residual disease.  相似文献   
4.
BackgroundReference values for cardiac magnetic resonance imaging (cMRI) in children and young adults are scarce. This leads to risk stratification of patients with congenital heart diseases being based on volumes indexed to body surface area (BSA). We aimed to produce cMRI Z score equations for ventricular volumes in children and young adults and to test whether indexing to BSA resulted in an incorrect assessment of ventricular dilation according to sex, body composition, and growth.MethodsWe retrospectively included 372 subjects aged < 26 years with either normal hearts or conditions with no impact on ventricular volumes (reference group), and 205 subjects with repaired tetralogy of Fallot (TOF) aged < 26 years. We generated Z score equations by means of multivariable regression modelling. Right ventricular dilation was assessed with the use of Z scores and compared with indexing to BSA in TOF subjects.ResultsVentricular volume Z scores were independent from age, sex, and anthropometric measurements, although volumes indexed to BSA showed significant residual association with sex and body size. In TOF subjects, indexing overestimated dilation in growing children and underestimated dilation in female compared with male subjects, and in overweight compared with lean subjects.ConclusionsIndexed ventricular volumes measured with cMRI did not completely adjust for body size and resulted in a differential error in the assessment of ventricular dilation according to sex and body size. Our proposed Z score equations solved this problem. Future studies should evaluate if ventricular volumes expressed as Z scores have a better prognostic value than volumes indexed to BSA.  相似文献   
5.
Sixty-one patients with SAH due to rupture of a cerebral aneurysm, classified in Grades I to IV according to Hunt and Hess, received a constant venous infusion of Nimodipine in a dose of 2mg/h for at least 14 days, followed by an oral administration of 60 mg/6 h for at least 4 days. Patients admitted after the 6th day of SAH, patients with SAH but without aneurysm on the angiogram and patients in Grade V were excluded. Mortality in 30 patients of Grades I-II was 3.3%, in 31 patients of Grades III-IV 42%. In the latter group 1 patient died due to cerebral vasospasm. Transient vasospasm occurred in 2 patients of Grades I-II. Recovery was complete in both cases. Thus, incidence of cerebral vasospasm was 4.9%, the incidence of poor-outcome-vasospasm even only 1.6%. The syndrome of cerebral vasospasm seems to be more than only constriction of cerebral vessels. The deleterious effects of Ca2+ shift into vascular cells and into neural cells which causes irreversible damage are discussed. Early administration of a specific 'cerebral' calcium antagonist like Nimodipine after SAH will prevent the intracellular Ca2+ overloading, thus protecting the neural cells and preventing Ca2+-induced smooth-muscle contraction of cerebral vessels, which encourages ischaemic deficits after SAH. The preventive use of Nimodipine has markedly reduced the incidence of symptomatic vasospasm in our clinic.  相似文献   
6.
BACKGROUND: Dehydroepiandrosterone (DHEA) has been suggested as an immunostimulating steroid hormone, of which the effects on the development of dendritic cells (DC) are unknown. The effects of DHEA often oppose those of the other adrenal glucocorticoid, cortisol. Glucocorticoids (GC) are known to suppress the immune response at different levels and have recently been shown to modulate the development of DC, thereby influencing the initiation of the immune response. Variations in the duration of exposure to, and doses of, GC (particularly dexamethasone (DEX)) however, have resulted in conflicting effects on DC development. AIM: In this study, we describe the effects of a continuous high level of exposure to the adrenal steroid DHEA (10 M) on the generation of immature DC from monocytes, as well as the effects of the opposing steroid DEX on this development. RESULTS: The continuous presence of DHEA (10 M) in GM-CSF/IL-4-induced monocyte-derived DC cultures resulted in immature DC with a morphology and functional capabilities similar to those of typical immature DC (T cell stimulation, IL-12/IL-10 production), but with a slightly altered phenotype of increased CD80 and decreased CD43 expression (markers of maturity). The continuous presence of DEX at a concentration of 10 M in the monocyte/DC cultures resulted in the generation of plastic-adherent macrophage-like cells in place of typical immature DC, with increased CD14 expression, but decreased expression of the typical DC markers CD1a, CD40 and CD80. These cells were strongly reactive to acid phosphatase, but equally capable of stimulating T cell proliferation as immature DC. The production of IL-12 by these macrophage-like cells was virtually shut down, whereas the production of IL-10 was significantly higher than that of control immature DC. CONCLUSION: The continuous presence of a high level of GC during the generation of immature DC from monocytes can modulate this development away from DC towards a macrophage-like cell. The combination of a low CD80 expression and a shutdown of IL-12 production suggests the possibility of DEX-generated cells initiating a Th2-biased response. These effects by DEX on DC development contrast with those by DHEA, which resulted in a more typical DC although possessing a phenotype possibly indicating a more mature state of the cell.  相似文献   
7.
Stability of fibrin sealant in cerebrospinal fluid: an in vitro study   总被引:2,自引:0,他引:2  
Menovsky T  de Vries J  van den Bergh Weerman M  Grotenhuis JA 《Neurosurgery》2002,51(6):1453-5; discussion 1455-6
OBJECTIVE: The in vitro stability of fibrin sealant in cerebrospinal fluid (CSF) was investigated to verify the efficacy of intracranial application of fibrin sealant. METHODS: Human CSF was collected from 11 patients. Fibrin glue spheres (diameter, 5 mm) were incubated in CSF specimens at 37 degrees C. At 2, 4, 8, 24, and 48 hours, the diameter of the spheres was measured and the ultrastructure was evaluated by transmission electron microscopy. A control group consisted of sealant spheres in physiological saline (n = 2). RESULTS: In all CSF samples, the fibrin sealant did not degrade with time. The size, consistency, color, and shape of the sealant remained unchanged, even 48 hours after placement in the CSF. Transmission electron microscopic analysis of the fibrin sealant revealed an amorphous, fibrinous meshwork. No morphological differences existed between fibrin sealant complex placed in the CSF for different time periods and sealant placed in physiological saline. CONCLUSION: Within the limitations of this in vitro study, human CSF has no adverse effects on fibrin sealant in terms of alteration of structure and morphology. Fibrin sealant is stable in a CSF environment and can be effectively used in the cisternal or subarachnoidal space.  相似文献   
8.
OBJECT: In this study the authors evaluate the safety, efficacy, and indications for endoscopic third ventriculostomy (ETV) in patients with a history of subarachnoid hemorrhage or intraventricular hemorrhage (IVH) and/or cerebrospinal fluid (CSF) infection. METHODS: The charts of 101 patients from seven international medical centers were retrospectively reviewed; 46 patients had a history of hemorrhage, 42 had a history of CSF infection, and 13 had a history of both disorders. All patients experienced third ventricular hydrocephalus before endoscopy. The success rate for treatment in these three groups was 60.9, 64.3, and 23.1%, respectively. The follow-up period in successfully treated patients ranged from 0.6 to 10 years. Relatively minor complications were observed in 15 patients (14.9%), and there were no deaths. A higher rate of treatment failure was associated with three factors: classification in the combined infection/hemorrhage group, premature birth in the posthemorrhage group, and younger age in the postinfection group. A higher success rate was associated with a history of ventriculoperitoneal (VP) shunt placement before ETV in the posthemorrhage group, even among those who had been born prematurely, who were otherwise more prone to treatment failure. The 13 premature infants who had suffered an IVH and who had undergone VP shunt placement before ETV had a 100% success rate. The procedure was also successful in nine of 10 patients with primary aqueductal stenosis. CONCLUSIONS: Patients with obstructive hydrocephalus and a history of either hemorrhage or infection may be good candidates for ETV, with safety and success rates comparable with those in more general series of patients. Patients who have sustained both hemorrhage and infection are poor candidates for ETV, except in selected cases and as a treatment of last resort. In patients who have previously undergone shunt placement posthemorrhage, ETV is highly successful. It is also highly successful in patients with primary aqueductal stenosis, even in those with a history of hemorrhage or CSF infection.  相似文献   
9.
BACKGROUND: Cerebrospinal fluid (CSF) leaks are widely recognized as commonly occurring postoperative complications of neurosurgical procedures. We will focus on the direct costs associated with CSF leaks in a single center across multiple neurosurgical procedures, based on a retrospective analysis. We will also compare the costs of using a synthetic agent to prevent such leaks with these costs from a more recent study. METHODS: The single-center retrospective study was carried out at the Neurosurgical Center Nijmegen (University Medical Center St Radboud and Canisius Wilhelmina Hospital, Nijmegen, Netherlands) from January 01, 1999, until December 31, 1999. Four hundred twelve consecutive, nontrauma, elective procedures were examined. RESULTS: By applying strict criteria for CSF leakage (including those self-limiting subcutaneous minor CSF collection), we found an overall leak rate of 10.7% with a lower number for supratentorial and transsphenoidal procedures and much higher numbers for infratentorial procedures and extensive skull base procedures (6 [12.8%] of 47 and 18 [34.6%] of 52, respectively). The CSF leak in these 44 patients was associated with high additional costs which accounted for 21.7% of the total costs of all 412 procedures or on average 1508 per patient and procedure. If DuraSeal (Confluent Surgical, Inc, Waltham, MA) were to be used prophylactically for every procedure, and assuming a 4% leak rate postprocedure (which was achieved in a more recent study of 46 patients using DuraSeal), there would be a saving of 550 for every procedure (reduction in additional costs of CSF leak minus the cost of the sealant), or a total saving of 226600 in the series of 412 patients. CONCLUSION: Our analysis establishes that CSF leaks occur with high frequency and incur significant costs across all types of surgical procedures. A direct correlation of this complication (and ensuring costs) is observed with more extensive procedures, and reduction of these significant costs can be achieved by using augmentation of the dural closure with DuraSeal.  相似文献   
10.

Purpose

To evaluate the oncological impact of postponing radical cystectomy (RC) to allow further conservative therapies prior to progression in a large multicentre retrospective cohort of T1-HG/G3 patients initially treated with BCG.

Methods

According to the time of RC, the population was divided into 3 groups: patients who did not progress to muscle-invasive disease, patients who progressed before radical cystectomy and patients who experienced progression at the time of radical cystectomy. Clinical and pathological outcomes were compared across the three groups.

Results

Of 2451 patients, 509 (20.8%) underwent RC. Patients with tumors?>?3 cm or with CIS had earlier cystectomies (HR?=?1.79, p?=?0.001 and HR?=?1.53, p?=?0.02, respectively). Patients with tumors?>?3 cm, multiple tumors or CIS had earlier T3/T4 or N?+?cystectomies. In patients who progressed, the timing of cystectomy did not affect the risk of T3/T4 or N?+?disease at RC. Patients with T3/T4 or N?+?disease at RC had a shorter disease-specific survival (HR?=?4.38, p?<?0.001), as did patients with CIS at cystectomy (HR?=?2.39, p?<?0.001). Patients who progressed prior to cystectomy had a shorter disease-specific survival than patients for whom progression was only detected at cystectomy (HR?=?0.58, p?=?0.024)

Conclusions

Patients treated with RC before experiencing progression to muscle-invasive disease harbor better oncological and survival outcomes compared to those who progressed before RC and to those upstaged at surgery. Tumor size and concomitant CIS at diagnosis are the main predictors of surgical treatment while tumor size, CIS and tumor multiplicity are associated with extravesical disease at surgery.
  相似文献   
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