Turboprop: improved PROPELLER imaging.

A variant of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) MRI, called turboprop, is introduced. This method employs an oscillating readout gradient during each spin echo of the echo train to collect more lines of data per echo train, which reduces the minimum scan time, motion-related artifact, and specific absorption rate (SAR) while increasing sampling efficiency. It can be applied to conventional fast spin-echo (FSE) imaging; however, this article emphasizes its application in diffusion-weighted imaging (DWI). The method is described and compared with conventional PROPELLER imaging, and clinical images collected with this PROPELLER variant are shown.     

Repeated survey on changes in musculoskeletal complaints relative to age and work demands.

OBJECTIVES: To examine changes in musculoskeletal complaints over four years in groups of employees relative to age and work demands. METHODS: Repeated questionnaire data of male employees in heavy physical work (exposed group, n = 7324) and mental work (control group, n = 4686), stratified for age (20-9, 30-9, 40-9, 50-9), were analysed. For each employee, data on the occurrence of musculoskeletal complaints from two surveys with a mean interval of around four years were available. Changes in prevalences over the follow up interval were analysed. Proportions of new, recovered, and chronic cases as well as those free of complaints at both surveys were studied. RESULTS: For most complaints, there were significantly greater increases in prevalences in the exposed group compared with the control group over the follow up interval particularly within the group aged 40-9 for back, neck, and several sites of the upper and lower limbs. The 20-9 year age group also had significantly greater changes for several musculoskeletal complaints. Within the oldest age group (50-9) exposure to heavy physical work demands only affected changes in prevalences of neck and upper arm complaints. After four years in the cohort free of complaints at the start of the follow up the group aged 40-9 had the highest prevalence of complaints of the back, neck, and the upper and lower limbs. CONCLUSIONS: Middle aged and younger employees develop musculoskeletal complaints as a result of exposure to heavy physical work. In the oldest age group health related selection seems to mask the occupational health risks under study. To prevent the expected increase in musculoskeletal disorders and related work disability in our aging workforce, preventive measures should be taken at all stages of a working life.     

Epidemiology of headache in Europe

The present review of epidemiologic studies on migraine and headache in Europe is part of a larger initiative by the European Brain Council to estimate the costs incurred because of brain disorders. Summarizing the data on 1-year prevalence, the proportion of adults in Europe reporting headache was 51%, migraine 14%, and 'chronic headache' (i.e. > or =15 days/month or 'daily') 4%. Generally, migraine, and to a lesser degree headache, are most prevalent during the most productive years of adulthood, from age 20 to 50 years. Several European studies document the negative influence of headache disorders on the quality of life, and health-economic studies indicate that 15% of adults were absent from work during the last year because of headache. Very few studies have been performed in Eastern Europe, and there are also surprisingly little data on tension-type headache from any country. Although the methodology and the quality of the published studies vary considerably, making direct comparisons between different countries difficult, the present review clearly demonstrates that headache disorders are extremely prevalent and have a vast impact on public health. The data collected should be used as arguments to increase resources to headache research and care for headache patients all over the continent.     

Interactive effects of ozone and formaldehyde on the nasal respiratory lining epithelium in rats

The combined effects on the nasal epithelium of mixtures of ozone and formaldehyde at cytotoxic and noncytotoxic concentrations were examined. Male Wistar rats were exposed by inhalation during 22 h/d for 3 consecutive days to 0.3, 1.0, or 3.0 ppm formaldehyde, or to 0.2, 0.4, or 0.8 ppm ozone, or to mixtures of 0.4 ppm ozone and 0.3, 1.0, or 3.0 ppm formaldehyde, or to 1.0 ppm formaldehyde and 0.2, 0.4, or 0.8 ppm ozone, or they were sham-exposed to clean air. The noses were examined for pathological changes at six standard cross levels by light microscopy and for epithelial cell proliferation by counting [3H-methyl]thymidine-labeled cells at cross levels II and III. Ozone at 0.4 ppm or 0.8 ppm or formaldehyde at 3 ppm enhanced cell proliferation at cross level II at all locations, except for the epithelium of the septum, which was not affected by ozone. At cross level III ozone alone did not induce cell proliferation, but formaldehyde at 0.3 and 1 ppm tended to reduce cell proliferation while at 3 ppm proliferation was slightly stimulated. The combined exposure to 0.4 ppm ozone and 0.3 ppm formaldehyde induced less cell proliferation at cross levels II and III when compared with that of 0.4 ppm ozone alone. Less cell proliferation was also seen at cross level II when animals were exposed to 0.4 or 0.8 ppm ozone in combination with 1 ppm formaldehyde than when exposed to these ozone concentrations alone. A more than additive increase in cell proliferation was found at cross level II after exposure to 0.4 ppm ozone in combination with 3 ppm formaldehyde, and at cross level III in animals exposed to 0.4 ppm ozone and 1 or 3 ppm formaldehyde. Treatment-related histopathological nasal changes, such as disarrangement, loss of cilia, and hyper/metaplasia of the epithelium were seen at 0.2, 0.4, and 0.8 ppm ozone and at 3 ppm formaldehyde. Simultaneous exposure to both materials did not noticeably affect type, degree, and size of the microscopic nasal lesions.     

Depression and anxiety disorders associated with headache frequency. The Nord‐Trøndelag Health Study

The aim of this large cross‐sectional population‐based study was to examine the association between migraine, non‐migrainous headache and headache frequency with depression, and anxiety disorders. From 1995 to 1997, all 92 566 inhabitants aged 20 years and above in Nord‐Trøndelag County in Norway were invited to participate in the Nord‐Trøndelag Health Study (‘Helseundersøkelsen i Nord‐Trøndelag’ = HUNT‐2). A total of 64 560 participated, whereof 51 383 subjects (80%) completed a headache questionnaire that was included. Of these 51 383 individuals, 47 257 (92%) completed the depression subscale items and 43 478 (85%), the anxiety subscale items of the Hospital Anxiety and Depression Scale (HADS). Associations were assessed in multivariate analyses, estimating prevalence odds ratios (OR) with 95% confidence intervals (CI). Depression and anxiety disorders as measured by HADS, were significantly associated with migraine (OR = 2.7, 95% CI 2.3–3.2; OR = 3.2, 95% CI 2.8–3.6) and non‐migrainous headache (OR = 2.2, 95% CI 2.0–2.5; OR = 2.7, 95% CI 2.4–3.0) when compared with headache‐free individuals. The association was stronger for anxiety disorders than for depression. The ORs for depression and anxiety disorders amongst both migraine and non‐migrainous sufferers increased with increasing headache frequency. Depression and anxiety disorders are associated with both migraine and non‐migrainous headache, and this association seems more dependent on headache frequency than diagnostic category.