Effect of endoscopic ultrasonography on the management of 100 consecutive patients with oesophageal and junctional carcinoma

BACKGROUND

Endoscopic ultrasonography (EUS) offers very accurate tumour and node staging information for oesophagogastric cancer. The aim was to determine whether the addition of EUS directly influenced the definitive management plan for individual patients.

METHODS

Personal and staging information from 100 consecutive patients with carcinoma of the oesophagus or oesophagogastric junction were summarized and blinded. Three consultant oesophagogastric surgeons independently made a management decision for each patient, in the presence and absence of the EUS data. All scored their perceived value of the EUS staging data for each patient.

RESULTS

EUS was deemed useful in 63-87 per cent of patients and its addition resulted in an increased number of concordant management plans (from 53 to 62 per cent), and increased agreement between surgeons. The greatest change in concordant management was an increased referral of patients for non-surgical palliation.

CONCLUSION

The addition of EUS to the staging of patients with oesophageal and oesophagogastric junction cancer significantly altered the management strategy for some of these patients.

Comparison of diagnostic quality of motion picture experts group-2 digital video with super VHS videotape for echocardiographic imaging

BACKGROUND

Motion Picture Experts Group-2 (MPEG2) is a broadcast industry standard that allows high-level compression of echocardiographic data. Validation of MPEG2 digital images compared with super VHS videotape has not been previously reported.

METHODS

Simultaneous super VHS videotape and MPEG2 digital images were acquired. In all, 4 experienced echocardiographers completed detailed reporting forms evaluating chamber size, ventricular function, regional wall-motion abnormalities, and measures of valvular regurgitation and stenosis in a blinded fashion. Comparisons between the 2 interpretations were then performed and intraobserver concordance was calculated for the various categories.

RESULTS

A total of 80 paired comparisons were made. The overall concordance rate was 93.6% with most of the discrepancies being minor (4.1%). Concordance was 92.4% for left ventricle, 93.2% for right ventricle, 95.2% for regional wall-motion abnormalities, and 97.8% for valve stenosis. The mean grade of valvular regurgitation was similar for the 2 techniques.

CONCLUSIONS

MPEG2 digital imaging offers excellent concordance compared with super VHS videotape.

Successful percutaneous closure of patent foramen ovale seven years after surgical closure

Through advancements in transcatheter technology, a patent foramen ovale (PFO) can now be closed by either a percutaneous or surgical procedure. This report presents a patient who suffered an embolic stroke secondary to a PFO. The PFO was successfully closed surgically, but 7 years later the foramen ovale was found to be widely patent. The patient underwent successful percutaneous PFO closure and the foramen ovale remains closed. This case demonstrates that percutaneous PFO closure may be viable in patients in whom surgical closure has not provided long-term closure.

The prospective role of transesophageal echocardiography in the diagnosis and management of patients with suspected infective endocarditis

STUDY OBJECTIVES

Transesophageal echocardiography (TEE) has a high sensitivity for the diagnosis of infective endocarditis (IE), but the prospective role of TEE when added to a careful clinical examination has not been well-studied.

DESIGN

We compared the results of TEE to a clinical evaluation by an infectious disease specialist in 43 consecutive patients in whom TEE was ordered to rule out IE. Prior to TEE, the patients were classified on clinical grounds as to their likelihood of IE using a modification of the von Reyn criteria. Changes in management occurring as a result of TEE also were evaluated.

MEASUREMENTS AND RESULTS

TEE was positive in 11 patients, negative in 29, and indeterminate in 3. TEE was positive in 6 (46%) of 13 high probability patients, 2 (67%) of medium probability patients, and 3 (11%) of 27 low probability patients. A change in management based on TEE occurred in 4 (31%) patients with high probability, in no patients with medium probability, and in 1 (4%) patient with low probability.

CONCLUSIONS

TEE confirms IE in patients with high probability of IE and often leads to a management change. However, TEE is unlikely to establish the diagnosis or change management in patients with low probability.

Can late survival of patients with moderate ischemic mitral regurgitation be impacted by intervention on the valve?

BACKGROUND

Ischemic mitral regurgitation is known to be associated with poor long-term outcome after coronary artery bypass grafting; however, our ability to alter that outcome with intervention on the valve is unclear. The decision to address the valve is most challenging for patients with only moderate mitral regurgitation, particularly with the popularization of off-pump surgery. We therefore reviewed early and late outcomes of patients undergoing revascularization with or without mitral valve surgery.

METHODS

Patients with moderate mitral regurgitation undergoing revascularization with and without mitral surgery between January 1991 and September 1996 were identified retrospectively. Operative notes were reviewed and patients with structural valve disease excluded. Perioperative events and late outcomes as determined by telephone contact and search of the social security death index (survival data 97% complete) were compared.

RESULTS

One hundred seventy-six patients with moderate mitral regurgitation underwent revascularization alone (n = 142) or with mitral repair or replacement (n = 34). Those undergoing revascularization alone had a higher serum creatinine, somewhat less mitral regurgitation, and lower New York Heart Association functional class preoperatively. Operative mortality was greater with valve surgery (21% vs 9%, p = 0.047). Actuarial survival of both groups at 5 years was similar (52% vs 58%, p = NS); however, when stratified by preoperative functional class, those with more advanced heart failure preoperatively had superior late survival if their mitral valve was intervened upon.

CONCLUSIONS

The late survival of patients with ischemic mitral regurgitation undergoing coronary revascularization remains poor; however, intervention on the mitral valve appears to benefit those with symptomatic heart failure.

The initial United States experience with the ATS mechanical cardiac valve prosthesis

From January 1, 1997 through June 30, 2000, 224 patients underwent valve replacement with the ATS Medical cardiac valve prosthesis under a USFDA-approved investigational device exemption study. Aortic valve replacement (AVR) was conducted in 152 patients (39 with coronary bypass) and mitral replacement (MVR) in 72 patients (18 with coronary bypass). Overall operative mortality was 1.8% (AVR = 2.8%, MVR = 0%), with only one valve-related death. In 372 patient-years of follow-up, there were an additional four patient deaths, two of which were valve related following a stroke. Valve-related complications included: thromboembolism (linearized rate = 3.8% per patient year), of which 3/11 had chronic deficits (0.8% per patient year); thrombosis (1 MVR = 0.8% per patient year); paravalvular leak (1 AVR = 0.4% per patient year); anticoagulant-related hemorrhage (1 AVR and 5 MVR = 1.6% per patient year) with no patient mortality; prosthetic valve endocarditis (1 MVR = 0.8% per patient year); and valve dysfunction (0%). Echocardiographic gradients were proportional to valve size and did not significantly change over the follow-up period. This study documented the ATS Medical prosthesis to be a valuable addition to the surgeon's armamentarium in the treatment of cardiac valvular disease.

A systematic review of the staging performance of endoscopic ultrasound in gastro-oesophageal carcinoma

BACKGROUND

Endoscopic ultrasound (EUS) may be used for preoperative staging of gastro-oesophageal carcinoma but performance values given in the literature differ.

AIMS

To identify and synthesise findings from all articles on the performance of EUS in tumour, node, metastasis (TNM) staging of gastro-oesophageal carcinoma.

SOURCE

Published and unpublished English language literature, 1981-1996.

METHODS

Data on the staging performance of EUS were retrieved and evaluated. Summary receiver operator characteristic methodology was used for synthesis, and a summary estimate of performance, Q*, obtained. Multiple regression analysis was used to assess study validity and investigate reasons for differences in performance.

RESULTS

Twenty seven primary articles were assessed in detail. Thirteen supplied results for staging oesophageal cancer, 13 for gastric cancer, and four for cancers at the gastro-oesophageal junction. For gastric T staging, Q*=0.93 (95% confidence interval (CI) 0.91-0.95) and for oesophageal T staging, Q*=0.89 (95% CI 0.88-0.92). For gastro-oesophageal T staging, including cancers at the gastro-oesophageal junction, Q*=0.91 (95% CI 0.89-0.93). Inclusion of cases with non-traversable stenosis was found to slightly reduce staging performance. For N staging, Q*=0.79 (95% CI 0.75-0.83). In articles that compared EUS directly with incremental computed tomography, EUS performed better. None of the variables assessed in the regression analysis was significant using a Bonferroni correction. Three variables (anatomical location, traversability, and blinding) showed strong relationships for future research and validation.

CONCLUSIONS

EUS is highly effective for discrimination of stages T1 and T2 from stages T3 and T4 for primary gastro-oesophageal carcinomas. The failure rate of EUS from non-traversability of a stenotic cancer may be a limitation in some patient groups.

Three-dimensional comparison of ultrastructural characteristics at depressing and facilitating synapses onto cerebellar Purkinje cells

Cerebellar Purkinje cells receive two distinctive types of excitatory inputs. Climbing fiber (CF) synapses have a high probability of release and show paired-pulse depression (PPD), whereas parallel fiber (PF) synapses facilitate and have a low probability of release. We examined both types of synapses using serial electron microscopic reconstructions in 15-d-old rats to look for anatomical correlates of these differences. PF and CF synapses were distinguishable by their overall ultrastructural organization. There were differences between PF and CF synapses in how many release sites were within 1 microm of a mitochondrion (67 vs 84%) and in the degree of astrocytic ensheathment (67 vs 94%). However, the postsynaptic density sizes for both types of synapses were similar (0.13-0.14 microm(2)). For both types of synapses, we counted the number of docked vesicles per release site to test whether this number determines the probability of release and synaptic plasticity. PF and CF synapses had the same number of anatomically docked vesicles (7-8). The number of docked vesicles at the CF does not support a simple model of PPD in which release of a single vesicle during the first pulse depletes the anatomically docked vesicle pool at a synapse. Alternatively, only a fraction of anatomically docked vesicles may be release ready, or PPD could result from multivesicular release at each site. Similarities in the number of docked vesicles for PF and CF synapses indicate that differences in probability of release are unrelated to the number of anatomically docked vesicles at these synapses.

Sibling, peer, neighbor, and schoolmate correlations as indicators of the importance of context for adolescent development

We use nationally representative data to calculate correlations in achievement and delinquency between genetically differentiated siblings within a family, between peers as defined by adolescents' "best friend" nominations, between schoolmates living in the same neighborhood, and between grademates within a school. We find the largest correlations between siblings, especially identical twins. Grademate and neighbor correlations are small. Peer-based correlations are considerably larger than grademate and neighbor correlations but not larger than most sibling correlations. The data suggest that family-based factors are several times more powerful than neighborhood and school contexts in affecting adolescents' achievement and behavior.

Cylindrical diameters method for calibrating section thickness in serial electron microscopy

An estimate of section thickness is required for measuring structures in serial section microscopy. Mean section thickness is estimated reliably by averaging the ratios of the diameters of cylindrical objects, such as mitochondria, to the number of sections they span. This cylindrical diameters method improves the accuracy of section thickness as inferred from the colour of sections floating in water. The cylindrical diameters method gives the same answer as that obtained by the minimal folds

METHOD

It is preferable because it can be done in a series that has no folds that can distort and obscure the objects that are being measured.

Overview on the structure, composition, function, development, and plasticity of hippocampal dendritic spines

There has been an explosion of new information on the neurobiology of dendritic spines in synaptic signaling, integration, and plasticity. Novel imaging and analytical techniques have provided important new insights into dendritic spine structure and function. Results are accumulating across many disciplines, and a step toward consolidating some of this work has resulted in Dendritic Spines of the Hippocampus. Leaders in the field provide a discussion at the level of advanced under-graduates, with sufficient detail to be a contemporary resource for research scientists. Critical reviews are presented on topics ranging from spine structure, formation, and maintenance, to molecular composition, plasticity, and the role of spines in learning and memory. Dendritic Spines of the Hippocampus provides a timely discussion of our current understanding of form and function at these excitatory synapses. We asked authors to include areas of controversy in their papers so as to distinguish results that are generally agreed upon from those where multiple interpretations are possible. We thank the contributors for their insights and thoughtful discussions. In this paper we provide background on the structure, composition, function, development, plasticity, and pathology of hippocampal dendritic spines. In addition, we highlight where each of these subjects will be elaborated upon in subsequent papers of this special issue of Hippocampus.

Extending unbiased stereology of brain ultrastructure to three-dimensional volumes

OBJECTIVE

Analysis of brain ultrastructure is needed to reveal how neurons communicate with one another via synapses and how disease processes alter this communication. In the past, such analyses have usually been based on single or paired sections obtained by electron microscopy. Reconstruction from multiple serial sections provides a much needed, richer representation of the three-dimensional organization of the brain. This paper introduces a new reconstruction system and new methods for analyzing in three dimensions the location and ultrastructure of neuronal components, such as synapses, which are distributed non-randomly throughout the brain.

DESIGN AND MEASUREMENTS

Volumes are reconstructed by defining transformations that align the entire area of adjacent sections. Whole-field alignment requires rotation, translation, skew, scaling, and second-order nonlinear deformations. Such transformations are implemented by a linear combination of bivariate polynomials. Computer software for generating transformations based on user input is described. Stereological techniques for assessing structural distributions in reconstructed volumes are the unbiased bricking, disector, unbiased ratio, and per-length counting techniques. A new general method, the fractional counter, is also described. This unbiased technique relies on the counting of fractions of objects contained in a test volume. A volume of brain tissue from stratum radiatum of hippocampal area CA1 is reconstructed and analyzed for synaptic density to demonstrate and compare the techniques.

RESULTS AND CONCLUSIONS

Reconstruction makes practicable volume-oriented analysis of ultrastructure using such techniques as the unbiased bricking and fractional counter methods. These analysis methods are less sensitive to the section-to-section variations in counts and section thickness, factors that contribute to the inaccuracy of other stereological methods. In addition, volume reconstruction facilitates visualization and modeling of structures and analysis of three-dimensional relationships such as synaptic connectivity.

The mechanisms mediating the effects of poverty on children's intellectual development

Although adverse consequences of poverty for children are documented widely, little is understood about the mechanisms through which the effects of poverty disadvantage young children. In this analysis we investigate multiple mechanisms through which poverty affects a child's intellectual development. Using data from the NLSY and structural equation models, we have constructed five latent factors (cognitive stimulation, parenting style, physical environment, child's ill health at birth, and ill health in childhood) and have allowed these factors, along with child care, to mediate the effects of poverty and other exogenous variables. We produce two main findings. First, the influence of family poverty on children's intellectual development is mediated completely by the intervening mechanisms measured by our latent factors. Second, our analysis points to cognitive stimulation in the home, and (to a lesser extent) to parenting style, physical environment of the home, and poor child health at birth, as mediating factors that are affected by lack of income and that influence children's intellectual development.

Identifying studies for systematic reviews. An example from medical imaging

OBJECTIVES

To determine if published figures on the proportion of articles included in systematic reviews and identified in electronic databases are applicable to an example from medical imaging.

METHODS

A systematic review was performed. Additionally, sensitivity and precision of a MEDLINE search were compared with values from three published searches, each customized for a specific field.

RESULTS

All articles included in the systematic review were in electronic databases. The MEDLINE search had low precision compared with searches in other fields.

CONCLUSIONS

In a specific area of medical imaging, electronic databases, including MEDLINE, are reliable sources of articles.

Congenital myasthenic syndrome with sleep hypoventilation

We report the case of a 13-year-old boy with acetylcholinesterase deficiency, a congenital myasthenic syndrome, who developed sleep hypoventilation syndrome during a period of rapid growth. His symptoms were insidious and life-threatening despite changes in strength or lung volume measurements that were not marked. He responded well to noninvasive nocturnal ventilation, with reversal of symptoms and normalization of blood gases. His lung volumes, but not motor function, improved after treatment.

Magnitude of left ventricular hypertrophy and risk of sudden death in hypertrophic cardiomyopathy

BACKGROUND

Sudden death is known to be a possible consequence of hypertrophic cardiomyopathy. Quantification of the risk of sudden death, however, remains imprecise for most patients with this disease.

METHODS

We assessed the relation between the magnitude of left ventricular hypertrophy and mortality in 480 consecutive patients with hypertrophic cardiomyopathy. The patients were categorized into five subgroups according to maximal wall thickness: 15 mm or less, 16 to 19 mm, 20 to 24 mm, 25 to 29 mm, and 30 mm or more. Their ages ranged from 1 to 89 years (median, 47).

RESULTS

Over a mean follow-up period of 6.5 years, 65 of the 480 patients (14 percent) died: 23 suddenly, 15 of heart failure, and 27 of noncardiac causes or stroke. The risk of sudden death increased progressively and in direct relation to wall thickness (P=0.001), ranging from 0 per 1000 person-years (95 percent confidence interval, 0 to 14.4) for a wall thickness of 15 mm or less to 18.2 per 1000 person-years (95 percent confidence interval, 7.3 to 37.6) for a wall thickness of 30 mm or more and almost doubling from each wall-thickness subgroup to the next. The cumulative risk 20 years after the initial evaluation was close to zero for patients with a wall thickness of 19 mm or less but almost 40 percent for wall thicknesses of 30 mm or more. As compared with the other subgroups, patients with extreme hypertrophy were the youngest (mean age, 31 years), and most (41 of 43) had mild symptoms or no symptoms; of the 12 patients who were less than 18 years old at the initial evaluation, 5 died suddenly.

CONCLUSIONS

In hypertrophic cardiomyopathy, the magnitude of hypertrophy is directly related to the risk of sudden death and is a strong and independent predictor of prognosis. Young patients with extreme hypertrophy, even those with few or no symptoms, appear to be at substantial long-term risk and deserve consideration for interventions to prevent sudden death. The majority of patients with mild hypertrophy are at low risk and can be reassured regarding their prognosis.

A case of confirmed nonbacterial thrombotic endocarditis with correlative transesophageal echocardiographic findings

The diagnosis of nonbacterial thrombotic endocarditis is rarely made during life. We describe a patient with non-Hodgkin's lymphoma with evidence of systemic embolism in which transesophageal echocardiography was useful in establishing the diagnosis. The clinical and echocardiographic features of nonbacterial thrombotic endocarditis should be remembered when a valvular mass is seen on echocardiography.

Valvular heart disease. Identifying and managing mitral and aortic lesions

Evaluation and treatment of valvular heart disease (table 1) are in evolution. Echocardiography is the principal diagnostic tool. In general, mitral and aortic stenotic lesions warrant surgical treatment when symptoms appear. Such intervention is also indicated in symptomatic patients with a regurgitant mitral or aortic lesion. Some patients with regurgitant lesions require surgical treatment even before the onset of symptoms, such as when left ventricular dysfunction or dilatation supervenes. Surgical treatment of valvular lesions consists of repair or replacement, except in the case of mitral stenosis, where PBMC is a reasonable alternative. In general, medical therapy has a very limited role in the treatment of valvular heart disease. Severe aortic insufficiency is an exception. In such cases, afterload reduction has proved beneficial in the long-term prognosis.