Comparison of positive allergy skin tests among asthmatic children from rural and urban areas living within small geographic area.

BACKGROUND: Evidence of increased asthma and allergic response among urban versus rural residents has been reported. OBJECTIVE: To evaluate the prevalence of allergic response among asthmatic children from urban and rural areas living within close proximity. METHODS: In all, 448 asthmatic children from urban (363) and rural (85) areas were studied. The study group consisted of 234 9-year-olds and 214 12-year-olds. A health questionnaire was completed on each child who subsequently underwent allergic skin prick tests (SPTs). RESULTS: There was significantly more positive SPT response to house-dust mite, mold, cat, and cypress among asthmatic children from urban areas compared with children living in rural areas: 58.3% versus 37.6%, 46.1% versus 31.8%, 17.45 versus 5.9%, and 26.2% versus 15.3%, respectively. Positive SPT for indoor allergens were significantly greater among asthmatic urban residents than asthmatic rural residents: 63.3% versus 45.5%, respectively (P < 0.02). Positive SPT response to all the allergens checked was higher among the 12-year-old age group when compared with the 9-year-olds, 34.6% versus 22.7%, respectively (P = 0.05). CONCLUSIONS: Allergic response measured by SPT is significantly more common among asthmatic children from urban areas as opposed to rural, even though both areas are within small distance of one another. Further, asthmatic children living in urban areas demonstrated more allergic response to both indoor and outdoor allergens. The allergic response tends to increase with increased age in both urban and rural asthmatic children.     

Digital recording, display, and storage of echocardiograms

Digital acquisition, display, and storage are new options available for handling echocardiographic images. These types of image management offer many practical advantages and are excellent supplements to standard videotape recordings. For routine M-mode and Doppler studies this digital approach, when combined with videotape, can virtually eliminate the necessity for strip chart recordings. Probably the principal advantage of digital storage techniques is for two-dimensional echocardiography. The continuous loop display is extremely convenient for rapid review, quantitation, and serial studies. When considering the implementation of these techniques, there are many limitations and practical considerations that must be kept in mind. Recording two-dimensional echocardiograms in a continuous loop mode requires that the same number of frames or cells must be used if one wants to display more than one image simultaneously. When creating a continuous loop of a single cardiac cycle, the number of cells and the interval between cells are greatly influenced by the heart rate. One must be able to display simultaneous images with varying heart rates. Last, the number of cells, the resolution, and the gray scale determine the amount of digital information that has to be stored, retrieved, or transmitted. The cost and size of the medium and the speed with which the images can be retrieved or transmitted become factors in how one elects to digitally acquire this information. One approach that has been used, which seems to work quite well in most cases, is to use an eight-cell sequence for two-dimensional echocardiograms. When primarily interested in looking at ventricular function, especially regional wall motion, a 50 msec interval between frames is most appropriate.(ABSTRACT TRUNCATED AT 250 WORDS)     

Digital echocardiography in myocardial infarction

Probably the most under-utilised application of echocardiography is in patients with coronary artery disease (CAD). This under-utilisation is striking since echocardiography can be very valuable in evaluating the natural history and therapy of CAD. One reason why echocardiography is not being utilised to its fullest is because of the reliance on videotape to record and display echocardiograms. This medium is time consuming and inconvenient for clinicians to review studies, it is not ideal for detecting subtle wall motion abnormalities, and videotape is impractical for comparing serial studies. Recording and storing echocardiograms on a digital medium overcomes these difficulties. Digital cine loops of single cardiac cycles provide great versatility. Multiple views or studies can be displayed simultaneously, subtle changes in wall motion are more easily detected and different views, or serial studies, can be readily compared. Such images can be displayed on computers on the ward or in the coronary care unit (CCU) and be available 24 hours a day, seven days a week at the convenience of the clinician. One does not need to find a recording on a two hour videotape, which may be in the ultrasound instrument, and one can view the exam in 30 sec instead of 5 to 10 min. Regional and global left ventricular function is one of the most important manifestations of CAD. With new therapeutic efforts at restoring myocardial function and limiting infant expansion, assessing LV function is more important than ever. Digital echocardiography is an extremely practical and convenient way for clinicians to obtain this information.