High specificity of the Pediatric Vision Scanner in a private pediatric primary care setting.

PURPOSE: To determine the specificity of the Pediatric Vision Scanner, a binocular retinal birefringence scanner, in its intended setting, a pediatric primary care office. METHODS: A total of 102 preschool children (age 2-6 years) were screened during a well-child pediatric visit using the Pediatric Vision Scanner and the SureSight Autorefractor and completed a masked comprehensive pediatric ophthalmic examination (gold standard examination). RESULTS: Based on the gold standard examination, one child had anisometropic amblyopia, and the remaining 101 had no amblyopia or strabismus. Specificity of the Pediatric Vision Scanner was 90% (95% CI, 82%-95%) while specificity of the SureSight was 87% (95%CI, 79-93%). Combining these results with the sensitivity of the devices determined in our previous study conducted in a pediatric ophthalmology office setting, the positive likelihood ratio for the Pediatric Vision Scanner was 10.2; for the SureSight, 5.0. The negative likelihood ratio for the Pediatric Vision Scanner was 0.03; for the SureSight, 0.42, a significant difference. CONCLUSIONS: The Pediatric Vision Scanner had high specificity (90%) in screening for amblyopia and strabismus as part of a pediatric well-child visit. Likelihood ratio analysis suggests that affected children have a high probability of being correctly identified by the Pediatric Vision Scanner. The high level of confidence conferred by Pediatric Vision Scanner screening may remove an important barrier to vision screening in pediatric primary care.

A consistent but non-coincident visual pattern facilitates the learning of spatial relations among locations.

Human participants searched in a dynamic three-dimensional computer-generated virtual-environment open-field search task for four hidden goal locations arranged in a diamond configuration located in a 5 × 5 matrix of raised bins. Participants were randomly assigned to one of two groups: visual pattern or visual random. All participants experienced 30 trials in which four goal locations maintained the same spatial relations to each other (i.e., a diamond pattern), but this diamond pattern moved to random locations within the 5 × 5 matrix from trial to trial. For participants in the visual pattern group, four locations were marked in a distinct color and arranged in a diamond pattern that moved to a random location independent of the hidden spatial pattern from trial to trial throughout the experimental session. For participants in the visual random group, four random locations were marked with a distinct color and moved to random locations independent from the hidden spatial pattern from trial to trial throughout the experimental session. As a result, the visual cues for the visual pattern group were consistent but not coincident with the hidden spatial pattern, whereas the visual cues for the visual random group were neither consistent nor coincident with the hidden spatial pattern. Results indicated that participants in both groups learned the spatial configuration of goal locations and that the presence of consistent but noncoincident visual cues facilitated the learning of spatial relations among locations.

Hypersalinity toxicity thresholds for nine California ocean plan toxicity test protocols.

Currently, several desalination facilities have been proposed to operate or are actually operating in California. These facilities' use of reverse osmosis (RO) may discharge hypersaline reject brine into the marine environment. The risks, if any, this brine would pose to coastal receiving waters are unknown. To test the toxicity of hypersaline brine in the absence of any additional toxic constituents, we prepared brine and tested it with the seven toxicity test organisms listed in the 2009 California Ocean Plan. The most sensitive protocols were the marine larval development tests, whereas the most tolerant to increased salinities were the euryhaline topsmelt, mysid shrimp, and giant kelp tests. Reject brines from the Monterey Bay Aquarium's RO desalination facility were also tested with three species. The effects of the aquarium's brine effluent on topsmelt, mussels, and giant kelp were consistent with those observed in the salinity tolerance experiments. This information will be used by regulators to establish receiving water limitations for hypersaline discharges.

Delivering pneumococcal vaccine to a high risk population: the Navajo experience.

High rates of preventable diseases such as pneumococcal disease occur among the Navajo despite their universal health insurance through the Indian Health Service. The objective of this study was to determine the proportion of Navajo adults vaccinated with pneumococcal polysaccharide vaccine and to examine key features of vaccination programs of the Navajo Indian Health Service. For this cross-sectional study, medical charts of Navajo patients with vaccine indications were randomly selected and reviewed to determine who had been vaccinated as of January 1, 1999. Among 480 Navajo>or=65 years old, 73% were vaccinated (95% confidence interval [CI]: 69%-77%). Among 111 Navajo 18-64 years old with vaccine indications, 54% were vaccinated (95% CI: 45% -63%). Vaccination programs utilized extensive public health nursing, home visits, standing orders, and "express lane" clinics. In spite of excellent delivery systems and universal healthcare, the proportion of Navajo persons vaccinated was still below the goals for Healthy People 2010 of having 90% of persons>or=65 years old vaccinated and 60% of high-risk persons 18-64 years old vaccinated.

Nasopharyngeal versus oropharyngeal sampling for detection of pneumococcal carriage in adults.

Several studies have shown that nasopharyngeal sampling is more sensitive than oropharyngeal sampling for the detection of pneumococcal carriage in children. The data for adults are limited and conflicting. This study was part of a larger study of pneumococcal carriage on the Navajo and White Mountain Apache Reservation following a clinical trial of a seven-valent pneumococcal conjugate vaccine. Persons aged 18 years and older living in households with children enrolled in the vaccine trial were eligible. We collected both nasopharyngeal and oropharyngeal specimens by passing a flexible calcium alginate wire swab either nasally to the posterior nasopharynx or orally to the posterior oropharynx. Swabs were placed in skim milk-tryptone-glucose-glycerin medium and frozen at -70 degrees C. Pneumococcal isolation was performed by standard techniques. Analyses were based on specimens collected from 1,994 adults living in 1,054 households. Nasopharyngeal specimens (11.1%; 95% confidence interval [CI], 9.8 and 12.6%) were significantly more likely to grow pneumococci than were oropharyngeal specimens (5.8%; 95% CI, 4.8 to 6.9%) (P < 0.0001). Few persons had pneumococcal growth from both specimens (1.7%). Therefore, both tests together were more likely to identify pneumococcal carriage (15.2%; 95% CI, 13.7 to 16.9%) than either test alone. Although we found that nasopharyngeal sampling was more sensitive than oropharyngeal sampling, nasopharyngeal sampling alone would have underestimated the prevalence of pneumococcal carriage in this adult population. Sampling both sites may give more accurate results than sampling either site alone in studies of pneumococcal carriage in adults.

Effectiveness of the 23-valent polysaccharide vaccine against invasive pneumococcal disease in Navajo adults.

Invasive pneumococcal disease occurs 2-3-fold more often among Navajo adults than among adults in the general United States population. The objective of this observational study was to determine the effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPV23) among Navajo adults. Active surveillance identified cases of invasive pneumococcal disease during 1996-1997. Three control patients per case patient were matched according to underlying medical conditions, sex, age, and location of medical care. Effectiveness was calculated by regression analysis of case-control sets and by indirect cohort methodology. Diabetes and alcoholism occurred in 41% and 43% of 108 case patients, respectively; 62% of case patients and 64% of control patients were immunized. Overall vaccine effectiveness was 26% (95% confidence interval [CI], -29% to 58%); 15% (95% CI, -116% to 67%) for patients with diabetes and -5% (95% CI, -141% to 54%) for patients with alcoholism. Overall vaccine effectiveness, as determined by use of the indirect cohort methodology, was 35% (95% CI, -33% to 69%). PPV23 was not significantly effective among Navajo adults and may be inadequate to prevent serious pneumococcal disease in this population.

Venous thrombosis associated with peripherally inserted central catheters: a retrospective analysis of the Cleveland Clinic experience.

Peripherally inserted central catheters (PICCs) have become popular for long courses of intravenously administration of antibiotics. Although these devices are generally regarded as safe, thrombotic complications have been associated with their use. In a retrospective review, 51 (2.47%) of 2063 patients who had a PICC placed during 1994-1996 were found to have developed a total of 52 PICC-associated venous thromboses (VTs). Two patients received the diagnosis of pulmonary embolism that was a complication of VT. Risk factors for VT identified by multiple logistic regression analysis were younger age, history of VT, discharge to a skilled-nursing facility, and therapy with amphotericin B. VT is a significant complication of PICC placement. It may occur more frequently than previously recognized and may be complicated by pulmonary embolism. Clinicians should maintain a high index of suspicion, especially for high-risk patients.