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Objectives: To describe the UK Food Surveillance System (FSS UK) currently in operation in Scotland and Northern Ireland, and being introduced UK-wide, particularly in relation to the development, scope and roll-out of the system. Study design: Pilot questionnaire, followed by pilot information technology (IT)-based study and subsequent roll-out. Methods: A paper-based trial of data collection was introduced, followed by an IT-based pilot and the subsequent development of an IT-based system and an Internet-based resource. A project working group and specific user groups were formed to assist the dedicated project team to progress the project. The groups' compositions reflect the interests of the various partner organizations, including the involvement of the Food Standards Agency. Results: Following the successful pilot study, Health Protection Scotland was commissioned by the Food Standards Agency to develop and roll-out FSS UK to councils and their partner laboratories throughout the UK within a 3-year period. Conclusion: The development of FSS UK provides the opportunity to compare and contrast national food sample data, highlight emerging food-related trends and provide an early warning system for food-related issues. [ABSTRACT FROM AUTHOR]

Serious errors can occur with many medical devices (e.g., infusion pumps, ventilators, anesthesia machines), and even highly trained professionals can make critical errors. The FDA now requires that manufacturers consider the user when designing medical equipment and has issued a guidance document describing human factor (HF) problems and the HF design process. The Association for Advancement of Medical Instrumentation has also published guidelines, and the American Medical Association's National Patient Safety Foundation has selected reduction of medical errors as their mission. It is important that the medical community reinforce the patient-safety initiative by evaluating user-interface design and instructional manuals when purchasing such equipment. The payoff will be fewer incidents and less time required in device training. The FDA actively solicits help in identifying and reporting adverse events associated with medical devices. Health care practitioners employed by facilities subject to the FDA's user-facility reporting requirements should follow the user-reporting procedures established by their facility. Practitioners and users may want to directly report an incident to the MedWatch Program, the FDA's voluntary Medical Products Reporting Program.

Objective: To evaluate magnetic resonance imaging (MRI) brain scans of dogs with pituitary-dependent hyperadrenocorticism (PDH) and no signs of CNS dysfunction 1 year after diagnosis and initial MRI., Design: Prospective study of surviving dogs from a previous study., Animals: 13 dogs underwent MRI of the brain at the time that PDH was diagnosed and prior to treatment. At that time, none of the dogs had clinical signs suggestive of an intracranial mass. Approximately 1 year after diagnosis and MRI, the brain was again evaluated by MRI., Results: On the initial MRI scan, 5 of the 13 dogs had normal findings, and 8 had evidence of a mass (tumor) in the area of the pituitary gland. Of the 5 dogs that had no visible pituitary mass on the initial MRI scan, 3 had a normal MRI brain scan 1 year later. Of the 5 dogs that had no visible pituitary mass on initial MRI scan, 2 had a visible pituitary mass at 1 year. The 8 dogs that had a visible mass on the initial MRI brain scan had easily identified pituitary masses on the second MRI scan. Of these 8 dogs, 4 had no apparent change in pituitary mass size, and 4 had obvious increase in vertical height of the pituitary mass. Of the 4 dogs, 2 developed signs of neurologic dysfunction within 1 year after diagnosis of PDH, presumably attributable to that mass. Of the 13 dogs, 12 were treated with mitotane soon after completion of the initial MRI scan. Sensitivity to mitotane and initial pituitary mass size or growth were not correlated. Of the 13 dogs evaluated initially and 1 year after diagnosis, 10 had pituitary masses identified on MRI brain scans., Clinical Implications: The incidence of visible pituitary masses among dogs with PDH at the time of or within a year of diagnosis was > 75%. In 2 dogs, signs of CNS dysfunction developed within 1 year of PDH diagnosis when pituitary masses were > or = 10 mm.

This study was designed to identify the source, risk factors, and clinical consequences of an outbreak of aluminum intoxication in hemodialysis patients using case-control and cohort studies. In 1991, a dialysis center in Pennsylvania [Dialysis Center A (DCA)] identified a number of patients with elevated serum aluminum levels. All patients receiving dialysis at DCA during January 1, 1987 to March 26, 1992 were involved in the study. A case-patient was defined as any patient with a serum aluminum level > or = 100 micrograms/liter after > or = 5 dialysis sessions at DCA. Fifty-nine case-patients were identified. Risk factors for elevated serum aluminum levels were receipt of bicarbonate- (rather than acetate-) based dialysate, higher number of sessions using bicarbonate dialysis, receipt of acid concentrate (used in bicarbonate dialysis) passed through one of two electric pumps, and a greater number of sessions using this concentrate. The electric pumps had an aluminum casing, casing cover, and impeller. Elevated levels of aluminum were found in acid concentrate after passing through a pump. Seizures and mental status changes requiring hospitalization were associated with aluminum exposure. We found that epidemic aluminum intoxication was caused by the use of an electric pump with aluminum housing to deliver acid concentrate used in bicarbonate dialysis. This outbreak demonstrates why it is essential to insure that all fluid pathways, storage tanks, central delivery systems, and pumps are compatible with low pH fluids before converting from acetate to bicarbonate dialysis.

Magnetic resonance imaging was used to determine the prevalence of visible pituitary masses in 21 dogs with recently diagnosed and untreated pituitary-dependent hyperadrenocorticism. All dogs had clinical signs and routine database values (CBC, serum biochemical panel, and urinalysis) consistent with a diagnosis of hyperadrenocorticism, and none had clinical signs suggestive of an intracranial mass. Each dog had plasma cortisol concentrations after adrenocorticotropic hormone administration or low-dose dexamethasone administration consistent with hyperadrenocorticism. Pituitary-dependent hyperadrenocorticism was confirmed by the finding of 2 equal-size adrenal glands on abdominal ultrasonography and by results of plasma endogenous adrenocorticotropic hormone concentration and high-dose dexamethasone suppression testing. Sagittal and transverse T1-weighted magnetic resonance images of the brain were obtained before and after IV administration of gadopentenate dimeglumine. Eleven dogs had visible masses, ranging in size from 4 to 12 mm at greatest vertical height. Mean age and body weight of dogs with a visible pituitary mass was not significantly different from dogs without a visible mass. There was no significant difference in endocrine test results when comparing dogs with a visible pituitary mass to dogs without. The prevalence of visible pituitary masses in dogs with pituitary-dependent hyperadrenocorticism was greater than suggested by the prevalence of clinical neurologic signs.

The value of magnetic resonance imaging (MRI) for the evaluation of dogs with pituitary-dependent hyperadrenocorticism (PDH) and CNS signs was assessed. Magnetic resonance imaging of the brain was performed in 13 dogs with PDH and neurologic signs. The diagnosis of PDH was made on the basis of results of adrenocortical function tests and abdominal ultrasonography, in conjunction with appropriate history, clinical signs, and clinicopathologic alterations. Eight dogs had been treated with the adrenocorticolytic agent, mitotane, for 1 to 30 months before the development of neurologic signs. Prior to MRI, each dog had progressive neurologic signs that could not be attributed to hypocortisolism or mitotane toxicosis. The neurologic signs most frequently detected were disorientation and ataxia. Mean age of dogs at the time neurologic signs developed was 9.5 years. Sex predilection was not detected; however, most were large-breed dogs, with 11 of the 13 dogs weighing more than 20 kg. A large mass in the pituitary gland, suprasellar region, or both was easily identified on the magnetic resonance images of each dog. The masses ranged from 8 to 24 mm in size. Expansion of tumors into the suprasellar region and compression of structures adjacent to the pituitary gland were readily detected by MRI. Contrast enhancement did not improve tumor identification, but did enable better delineation between tumor and surrounding structures. After the diagnosis of a macrotumor was made by MRI, radiotherapy was initiated in 9 dogs and was successfully completed in 6. Three dogs had a relapse of neurologic signs 8, 11, and 26 months after radiotherapy was completed.(ABSTRACT TRUNCATED AT 250 WORDS)

In September 1987, patients at an outpatient dialysis center were exposed to chloramine contaminated dialysate when the carbon filter in a recently modified water treatment system failed. Forty-one patients required transfusion to treat the resultant hemolytic anemia. Epidemiologic investigation demonstrated that the mortality rate among dialysis center patients increased during the 5 months after chloramine exposure when compared with the 12 months before chloramine exposure, but no deaths could be attributed to the exposure. Chloramine is commonly used as a disinfectant in municipal water supplies, and has previously been reported to cause hemolytic anemia in patients undergoing dialysis. Hemodialysis centers in cities that use chloramine in water supplies must design water treatment systems with adequate means for removing chloramine and must monitor processed water closely to ensure that chloramine contamination does not occur. Dialysis centers that make changes in their water processing systems should evaluate all components of the system before changes are made, and must ensure that after modifications are made, processed water meets the standards set by the Association for Advancement of Medical Instrumentation.

The water used for dialysate (dialysis fluid) in hemodialysis centers is produced by water treatment systems (WTS), which require careful and frequent monitoring. On November 3, 1988, nine patients receiving hemodialysis treatments at a single dialysis center suddenly developed hypotension within 30 minutes of onset of dialysis. Eight patients exhibited symptoms and two experienced syncopal episodes; there were no deaths. The incidence of dialysis-associated hypotension occurring within 30 minutes after dialysis onset for these patients was significantly higher during outbreak treatments than during preoutbreak (September 1 through November 2, 1988) treatments, (9 of 9 vs. 0 of 238, P less than 0.00001, Fisher's t-test). Sodium azide, a potent hypotensive agent, was identified as the probable contaminant within the WTS of the dialysis center at the time of the outbreak because: 1) it was mixed with glycerine as the preservative solution of each of the four ultrafilters that were put on-line in the WTS without rinsing, 12 hours before the outbreak; and 2) high levels of total organic carbons were detected from dialysis water collected at point-of-use sites at the time of the outbreak, suggesting contamination of the WTS with the sodium azide-glycerine preservative solution. To prevent similar occurrences, we recommend that ultrafilters (and other components of the WTS) be rinsed free of potentially toxic chemicals prior to use. Dialysis center personnel need to be aware of the potential affects that each modification of disinfection of the WTS may have upon the product water used to prepare dialysate for patient treatments.

Sonographic examination of the abdomen was performed in 20 patients with cystic fibrosis aged 3--41 years. The predominant acoustic architecture of the pancreas was one of moderate to markedly increased echogenicity when compared to the liver at the same depth. Increased echogenicity of the pancreas was independent of the presence of malabsorption. The usual reduced echo pattern associated with pancreatic inflammation was seen in only one of five cystic fibrosis patients with clinical evidence of pancreatitis. Other pancreatic abnormalities included pancreatic calcifications in one child with pancreatitis and a pseudocyst in an adult with pancreatitis. Eight patients had hepatosplenomegaly and gallstones were seen in two; one had a markedly contracted gallbladder. Sonography offers an effective method of following patients with cystic fibrosis.

A description of a new Doppler ultrasound flow measuring instrument is given along with representative measurements of blood flow in the canine renal artery and the human aortic arch, renal artery, and transplanted kidney renal artery. The instrument is briefly described, and a discussion of the limitations of the technique is presented.

The feasibility of using focused ultrasound for studying structures as small as biliary ducts and correlative radiological and ultrasonic studies of the common and larger hepatic ducts are presented. Patients whose bile ducts were visualized on intravenous or T-tube cholangiography or oral cholecystography underwent radiography with a metallic skin marker along the right anterior lower costal margin. The marker was then correlated with ultrasonic observations of multiple oblique scans parallel to the lower costal margin. The common duct could be identified in 15 of 21 patients. Ultrasonic visualization circumvents the problems of elevated serum bilirubin, iodine contrast media sensitivity, and pregnancy.

The interpretation of two-dimensional radiographs or computerized tomography (CT) or ultrasound (US) sections with inferences made about three-dimensional anatomy is the foundation of diagnostic radiology. A large variety of estimation methods which can be applied to two-dimensional CT/US sections to estimate their three-dimensional properties is presented. The techniques are easily utilized in a research or clinical setting, do not require computerization, and can provide statistically accurate three-dimensional information based on two-dimensional sampling with a minimum of effort. Although the examples are directed at diagnostic radiology, the estimation procedures may be employed in analogous fields such as microscopy or section anatomy.

A mammography screening program for breast cancer carried out in Sacramento by the University of California Davis School of Medicine, Davis, was canceled because of negative public reaction to sensationalized reports in the lay press on the potential carcinogenic risks of the radiation exposure, along with passivity on the part of the medical community in defending the procedure and the program. Disappointment in this occurrence spurred us to explore physician's knowledge of and attitudes toward breast cancer and mammography. The results confirmed our suspicions that a significant number of physicians lack accurate knowledge of breast cancer and of the extremely high benefit-to-risk ratio of mammography as a means of early detection.

Outpatient low-dose computed tomography metrizamide myelography (CTMM) for the evaluation of lumbar disk disease is described in 55 patients. Ten individuals (group 1) were studied using 3.5 ml of 150 mg I/ml (525 mg I total) of metrizamide. Forty-five additional patients (group 2) were examined with 5 ml of 110 mg I/ml (550 mg I total) concentration of metrizamide. Group 2 experienced less post-procedure headache (6.6%) and nausea (2.2%) than did group 1 (30% and 10%, respectively). Group 2 demonstrated a lowered rate of headache (p less than .01) and showed a trend to less nausea (p less than .09) than a recently published study describing full-dose lumbar myelography. In addition, CTMM in group 2 produced more uniform mixing of metrizamide than in group 1. Overall, low-dose CTMM increased accuracy and reduced morbidity, patient cost, and inconvenience as compared with routine full-dose lumbar myelography.

This article describes the first successful virus induction of sarcomas in adult immunosuppressed cats. The method of tumor induction, the immunosuppression regimen, and the gross, histologic, and angiographic findings in these induced sarcomas are described. The simplicity of the model, the rapid and reliable growth of the tumors, and the size of the animals permit repeated angiography. The model is well suited to studies of angiographically directed therapy with embolic agents, radioactive implants, or chemotherapeutic drugs. The use of a feline model permits repeated selective angiography, which is not the case with small laboratory animals, in which such studies are difficult. In this investigation, tumors were induced into the right hepatic lobe because of the relative homogeneity of peripheral hepatic vascularity and the ease with which early neoplastic changes can be detected. There is good evidence to indicate that virus induction sites in other organs would also be successful.

Seventeen proven cases of complete hydatidiform mole and 14 sonographically similar nonmolar cases were studied in detail with a variety of ultrasound transducers. Complete hydatidiform moles can be reliably differentiated from other lesions with similar sonographic appearances by using a highly focused ultrasound transducer to image the near field of the intrauterine contents.

An analytic method for detecting isodense subdural fluid collections from computed tomography (CT) scan pixel attenuation data is presented. Analysis of 44 CT scan levels from 8 patients with isodense subdural hematomas (ISDH) and 50 CT scan levels from 15 patients without ISDH indicates 6% false positive and 3% false negative errors if the analysis is restricted to noncontrast CT scans that demonstrate subcalvarial bilateral cortical attenuation symmetry in the pictorial display.

Useful clinical information will often result from determinations of organ and lesion tissue volumes from measurements of computed tomographic (CT) cross sections. This paper discusses simple applications of stereology to volume estimations of organs and disease processes. The method is applied to CT sections and, for equivalent accuracy, is less time consuming than planimeter or CT scanner region of interest outlining and measurements.

A new triple tracer indicator dilution technique has been used to measure alveolar ventilation as well as air and tissue volumes in the lungs of experimental animals and man. The tracers indocyanine green, [(121)I]antipyrine and xenon-133 were rapidly injected into the right atrium, while sampling was carried out from a peripheral artery. Blood flow and tissue volumes were obtained by classical analysis of the indocyanine green and antipyrine concentration-time curves. A double exit-port, constant air flow model was used to analyze the xenon curves, because ventilatory loss led to incomplete recovery of the gas tracer in effluent blood. Uniform ventilation and perfusion were assumed. This analysis permitted calculation of alveolar ventilation (VA(Xe)) and functional residual capacity (FRC(Xe)) during normal breathing. In control studies, VA(Xe) was similar to VA(co2), obtained with the steady-state CO(2) method (r = 0.87), while in critically ill patients the xenon measurement was significantly lower, averaging 54% of VA(co2). In theory, underestimates in VA(Xe) and decrease in the ratio VA(Xe)/VA(co2) relate to nonuniformity in regional ventilation and perfusion. The effect is greatest for the slightly soluble gas, xenon. The significant inverse correlation between VA(Xe)/VA(co2) and the physiologic shunt is consistent with this postulate.FRC(Xe) was similar to the predicted FRC in animals but was 76% of the helium measured FRC in patients. FRC(Xe) was significantly lower than the xenon measured air volumes during breath-holding when nonuniformity of ventilation was not operative. Lung tissue volumes in animals were 83% of gravimetric lung weights, while in patients the volumes were much lower than predicted. Nonhomogeneous lung function, including failure to perfuse the entire capillary bed, with resultant incomplete penetration of tracers into all segments of lung air and tissue, may explain these findings. The resultant errors can be significant in sick patients, and may themselves be used to study nonhomogeneities in the distribution of ventilation and volume.