Diagnostic accuracy of film-based, TIFF, and wavelet compressed digital temporomandibular joint images

The purpose of this research was to determine if digitization and the application of various compression routines to digital images of temporomandibular joint (TMJ) radiographs would diminish observer accuracy in the detection of specific osseous characteristics associated with TMJ degenerative joint disease (DJD). Nine observers viewed 6 cropped hard-copy radiographic films each of 34 TMJs (17 radiographic series). Regions of interest measuring 2 in x 2 in were digitized using an 8-bit scanner with transparency adapter at 300 dpi. The images were placed into a montage of 6 images and stored as tagged image file format (TIFF), compressed at 4 levels (25:1, 50:1, 75:1, and 100:1) using a wavelet algorithm, and displayed to the observers on a computer monitor. Their observations regarding condylar faceting, sclerosis, osteophyte formation, erosion, and abnormal shape were analyzed using ROC. Kappa values were determined for relative condylar size and condylar position within the glenoid fossa. Indices were compared using ANOVA at a significance level of P < .05. Although significant and substantial observer variability was demonstrated, there were no statistically significant differences between image modalities, except for condylar position, in which TIFF and wavelet (at all compression ratios) performed better than the original image. For faceting, wavelet 100:1 performed better than radiographic film images. Little actual image file reduction was achieved at compression ratios above 25:1.     

Desarrollo de estándares para la educación y formación en medicina familiar y comunitaria – contribuciones de la WONCA IberoAmérica (CIMF)

The WONCA Education Working Party (WEP) is developing a set of standards for medical student education, postgraduate training in family medicine / general practice and continuing professional development for family doctors. At this point the contributions by WONCA world regions are very important, and for this reason the main objective of this report is to present the standards developed by the Iberoamerican WONCA Region (CIMF). To be comprehensive and effective, standards should reflect regional realities and so the contributions from CIMF may reinforce and strengthen the key initiative of WEP and the implementation of the standards throughout the world.     

Three-Dimensional Computerized Tomographic Scanning of Craniofacial Anomalies

Three-dimensional images were reconstructed from conventional CT scans with the use of special software. These reconstructed images did not exhibit magnification nor superimpositioning of structures. Quantitative measurements of three-dimensional craniofacial structures were very precise, and their form and continuity could be evaluated. The application of this technique will be demonstrated in three cases involved with craniofacial anomalies.     

Cardiomyopathy induced by artificial cardiac pacing: myth or reality sustained by evidence?

Implantable cardiac pacing systems are a safe and effective treatment for symptomatic irreversible bradycardia. Under the proper indications, cardiac pacing might bring significant clinical benefit. Evidences from literature state that the action of the artificial pacing system, mainly when the ventricular lead is located at the apex of the right ventricle, produces negative effects to cardiac structure (remodeling, dilatation) and function (dissinchrony). Patients with previously compromised left ventricular function would benefit the least with conventional right ventricle apical pacing, and are exposed to the risk of developing higher incidence of morbidity and mortality for heart failure. However, after almost 6 decades of cardiac pacing, just a reduced portion of patients in general would develop these alterations. In this context, there are not completely clear some issues related to cardiac pacing and the development of this cardiomyopathy. Causality relationships among QRS widening with a left bundle branch block morphology, contractility alterations within the left ventricle, and certain substrates or clinical (previous systolic dysfunction, structural heart disease, time from implant) or electrical conditions (QRS duration, percentage of ventricular stimulation) are still subjecte of debate. This review analyses contemporary data regarding this new entity, and discusses alternatives of how to use cardiac pacing in this context, emphasizing cardiac resynchronization therapy.     

Impact of beta1-adrenergic receptor polymorphisms on susceptibility to heart failure, arrhythmogenesis, prognosis, and response to beta-blocker therapy

Beta1-adrenergic receptor polymorphisms have been implicated with inconsistent results in the pathogenesis, clinical presentation, and prognosis of patients with heart failure (HF). The impact of 2 functional polymorphisms (beta1-Arg389Gly and beta1-Ser49Gly) on HF susceptibility, arrhythmogenesis, and prognosis was evaluated in Brazilian outpatients. Genotyping at codons 389 and 49 was performed using polymerase chain reaction with restriction fragment length polymorphism analysis in 201 outpatients with systolic HF and 141 apparently healthy controls. Enrolled patients were followed up at the HF clinic, and vital status was evaluated using electronic hospital records, telephone contact, and a local death certificate database. Allele frequencies were similar between patients with HF and controls, with neither polymorphism related to HF susceptibility. The beta1-389Gly homozygotes had significantly less nonsustained ventricular tachycardia on Holter monitoring (17% vs 48% for Arg/Arg patients; p = 0.015) and improved HF-related survival, with no events after a median follow-up of 40 months (log-rank statistics = 0.025). The negative impact of beta1-389Arg allele on HF-related survival was substantially reduced using high-dose beta-blocker therapy (80% survival for high-dose vs 42% for low-dose beta blockers or nonusers; log-rank statistics = 0.0003). The beta1-Ser49Gly polymorphism was not associated with nonsustained ventricular tachycardia or HF prognosis. In conclusion, beta1-Arg389Gly and beta1-Ser49Gly polymorphisms had no influence on HF susceptibility. However, the Gly389 allele was associated with a lower prevalence of ventricular arrhythmias and better HF-related survival. A pharmacogenetic interaction is suggested because beta blockers were more effective in beta1-389Arg allele carriers.     

Accuracy of Dedicated Risk Scores in Patients Undergoing Primary Percutaneous Coronary Intervention in Daily Clinical Practice

Background

Comparisons between dedicated risk scores in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI) in real-world clinical practice are scarce. The aim of this study was to assess the diagnostic performance of the Global Registry of Acute Coronary Events (GRACE), Primary Angioplasty in Myocardial Infarction (PAMI), Thrombolysis in Myocardial Infarction (TIMI), and Zwolle scores in STEMI patients undergoing pPCI in contemporary clinical practice.

Methods

This was a prospective cohort study of consecutive patients with STEMI undergoing pPCI between December 2009 and November 2010 in a high-volume tertiary referral centre. The outcomes assessed were major cardiovascular events (MACEs) and death within 30 days. The diagnostic accuracy of the scores was assessed using receiver operating characteristic curves, and scores were compared using the DeLong method.

Results

During the study period, 501 patients were included. Within 30 days, 62 patients (12.4%) presented a MACE and 39 individuals (7.8%) died. All scores were statistically associated with death and MACE within 30 days (P < 0.01). The c-statistic and 95% confidence intervals for 30-day mortality were: GRACE, 0.84 (0.78-0.90); TIMI, 0.81 (0.74-0.87); Zwolle, 0.80 (0.73-0.87); and PAMI, 0.75 (0.68-0.82) (P < 0.01). There was no statistically significant difference regarding the accuracy of the TIMI, GRACE, and Zwolle scores for 30-day mortality, but the GRACE score was superior to the PAMI score (P < 0.01).

Conclusions

The TIMI, GRACE, and Zwolle scores performed equally well as predictors of mortality in patients who underwent pPCI in current practice. These results suggest that these scores are suitable options for risk assessment in a real-world setting.     

A comparison of video prompting with and without voice-over narration on the clerical skills of adolescents with Autism

The purpose of this study was to compare the effects of video prompting with and without voice-over narration on the acquisition of clerical skills among five secondary students with Autism Spectrum Disorder. We used an adapted alternating treatments design consisting of baseline, comparison, and best treatment conditions. Results showed there were negligible differences between video prompting with or without voice-over narration. However, participants indicated differing preferences for one method over the other.