New pressure sensing elements for FFR coronary catheter.

The next generation FFR Coronary Catheter includes a new stable pressure sensor, AD conversion at the tip of the catheter and mount of these components on the sidewall of the catheter instead of the guide wire enabling thus to use standard guide wires. The new ultrathin capacitive MEMS pressure sensor die with corresponding readout ASIC circuit offers better accuracy, robustness and automated assembly. The measured performance values of the fabricated chips correlate well with the simulated ones indicating comprehensive understanding of the sensor operation and control of the fabrication process. The test measurements outperformed the specifications for the FFR pressure sensing.

Relative bone mineral density measured by metacarpal index (MCI) and chronic spinal syndromes: an epidemiological study.

OBJECTIVES: The results of previous studies on the association between bone mineral density (BMD) and chronic spinal syndromes have been contradictory. Therefore, we studied relative BMD measured by the metacarpal index (MCI) and its associations with chronic neck and low-back syndromes and diffuse idiopathic skeletal hyperostosis (DISH). METHODS: A population sample of 8000 Finns aged 30 years and over was invited to a comprehensive health examination in 1978-1980; 90% complied. In the clinical phase, a trained physician diagnosed chronic neck and low-back syndromes. Hand and chest radiographs were taken from 3568 participants to determine the MCI and to diagnose DISH. Of these, 340 subjects were re-examined clinically in 2000. RESULTS: After adjusting for potential confounding factors, a high MCI showed a significant cross-sectional association with chronic neck syndrome and DISH. The odds ratio (OR) per increment of one standard deviation (0.1) of MCI for chronic neck syndrome was 1.33 [95% confidence interval (CI) 1.21-1.47] and for DISH 1.29 (95% CI 1.04-1.60). No association was found between MCI and chronic low-back syndrome. In the follow-up setting, however, baseline MCI did not predict the incidence of chronic neck or low-back syndromes. CONCLUSIONS: Relative BMD is directly proportional to the prevalence of chronic neck syndrome. Further studies are needed to clarify the mechanisms of the association. The close association found between high relative BMD and DISH suggests a joint metabolic factor, which needs to be studied further to determine its effects on bones and intervertebral discs.

Association of radiological hand osteoarthritis with bone mineral mass: a population study.

OBJECTIVES: A number of previous studies have reported an inverse relationship between osteoarthritis and osteoporosis. However, the association has remained controversial because osteoarthritis in hand joints seems to associate differently from osteoarthritis in weight-bearing joints with bone mineral mass. We studied osteoarthritis in distal interphalangeal (DIP) joints and osteoarthritis in the base of the thumb (CMC-1) for their cross-sectional associations with metacarpal cortical bone mineral mass, and for their prediction of calcaneal broadband ultrasound attenuation. METHODS: A population sample of 8000 Finns aged 30 yr and over was invited to a comprehensive health examination in 1978-1980; 90% complied. Hand radiographs were taken from 3568 participants to diagnose osteoarthritis in various hand joints, and to determine two indicators of cortical bone mineral mass, the combined cortical thickness (CCT) and the metacarpal index (MCI). Calcaneal broadband ultrasound attenuation was measured 20 yr later in 340 of these participants with the Sahara sonometer. RESULTS: In the cross-sectional setting, osteoarthritis in the DIP joints and osteoarthritis in the base of the thumb (CMC-1) were significantly associated with low CCT and low MCI. These associations were proportional to the radiological severity of osteoarthritis. In the follow-up setting, symmetrical DIP osteoarthritis adjusted for age, sex, body mass index, smoking, education, workload and MCI significantly predicted low values of broadband ultrasound attenuation. CONCLUSIONS: Our results indicate a direct relation of both radiological DIP osteoarthritis and CMC-1 osteoarthritis with low cortical bone mineral mass, in proportion to the severity of osteoarthritis. The presence of symmetrical DIP osteoarthritis, a possible indicator of generalized osteoarthritis, suggests an increased risk of osteoporosis over time.

Osteoarthritis of finger joints in Finns aged 30 or over: prevalence, determinants, and association with mortality.

BACKGROUND: Prevalence and risk factors of osteoarthritis (OA) in finger joints have been amply explored in previous studies. However, no study has focused on finger joint OA as a predictor of mortality. OBJECTIVE: To investigate finger joint OA for its associations with alleged risk factors and with life expectancy in an extensive health survey. METHODS: From 1978 to 1980 a representative population sample of 8000 Finns aged 30 years or over was invited to participate in a comprehensive health examination; 90% accepted. Hand radiographs were taken from 3595 subjects. By the end of 1994, 897 of these had died. RESULTS: The prevalence of OA of Kellgren's grade 2 to 4 in any finger joint and in at least two symmetrical pairs of distal interphalangeal joints (DIPs) was 44.8% and 16.0%, respectively. Age and body mass index were significant determinants for OA both in any finger joint and in symmetrical DIP OA. The history of physical workload in women showed a positive association with OA in any finger joint. Smoking in men seemed to protect against symmetrical DIP OA. As adjusted for the determinants above, symmetrical DIP OA predicted mortality in women (relative risk (RR), 1.23; 95% confidence interval (95% CI) 1.01 to 1.51), but not in men (RR 0.89; 95% CI 0.68 to 1.16). In men, however, OA in any finger joint significantly predicted cardiovascular deaths (RR 1.42; 95% CI 1.05 to 1.92). CONCLUSION: OA in any finger joint and symmetrical DIP OA have different risk factor profiles and predict mortality in different patterns between men and women.

Optical properties of spin-on deposited low temperature titanium oxide thin films.

This letter presents a method to fabricate high quality, high refractive index titanium oxide thin films by applying liquid phase spin-on deposition combined with low temperature annealing. The synthesis of the liquid form titanium oxide material is carried out using a sol-gel synthesis technique. The material can be annealed at low temperature (150 C degrees ) to achieve relatively high refractive index of 1.94 at 632.8 nm wavelength, whereas annealing at 350 C degrees results in index of 2.03 at 632.8 nm. Film depositions are demonstrated on silicon substrates with 0.5% uniformity in thickness. Refractive indices and extinction coefficients are characterized over a broad wavelength range to demonstrate the optical performance of this novel aqueous phase spin-on deposited hybrid titanium oxide material.

The effect of age and density of the breast on the sensitivity of breast cancer diagnostic by mammography and ultasonography.

PURPOSE: We studied which, age of the patient or density of the breast accounts for the sensitivity of mammography and ultrasonography (US). Furthermore we studied whether the overall impression on the density of the breast or the density in tumour area accounts for the sensitivity of mammography and ultrasonography. MATERIALS AND METHODS: The material consisted of 572 consecutive histologically and 5 cytologically verified breast cancer cases. Mammography and US examinations were performed immediately before breast cancer operations and information on the findings were received from the original patient files and classified as malignant or benign. The density of breast parenchyma to fatty, mixed or dense in total breast and separately in tumour area was defined by a radiologist group from the original mammograms by comparing to model mammograms. The sensitivity (Se) of mammography and US was compared in 3 age groups (26-49, 50-59 and 60-92) and in the different density classes. RESULTS: Sensitivity of mammography increased by age (density-adjusted OR = 0.2, 95%, CI 0.1-0.5) in age group 26-49 compared to age group 60-92) and with fattiness of the breast (age-adjusted OR= 0.4, 95%, CI 0.1-1.0 for dense breast parenchyma in tumour area compared to fatty breast). Sensitivity of US was inversely related to age (density-adjusted OR = 2.3, 95%, CI 1.0-5.2 in age group 26-49 compared to age group 60-92) and directly related with fattiness of breast (age-adjusted OR = 0.5, 95%, CI 0.2-0.9 by dense breast parenchyma in tumour area compared to fatty breast). Density in the tumour area compared to total breast density was related only mariginally better sensitivity both of mammography (0.4 vs. 0.6) and of US (0.5 vs. 0.6). CONCLUSION: Sensitivity of both mammography and sensitivity of US are independently related both to the age of the patient and to the density of the breast. The effect of age is inverse and that of density parallel between mammography and US on sensitivity. The effect of overall breast density was close to the effect of density at the site of the tumour on the sensitivity of both mammography and US.

The visibility of cancer on previous mammograms in retrospective review.

AIM: To study how many tumours were visible in restrospect on mammograms originally reported as normal or benign in patients coming to surgery with proven breast cancer. The effect of making the pre--operative mammogram available was also assessed. MATERIALS AND METHODS: Three hundred and twenty initial mammograms of consecutive new breast cancer cases were analysed by a group of radiologists in the knowledge that all patients were later diagnosed with breast cancer. The films were read twice, first without and then with the later (pre-operative) mammograms available. The parenchymal density in the location of the tumour was classified as fatty, mixed or dense, and the tumours were classified as visible or not visible. The reasons for the invisibility of the tumour in the earlier examination were analysed. RESULTS: Fourteen per cent (45) of cancers were retrospectively visible in earlier mammograms without the pre-operative mammograms having been shown, and 29% (95) when pre-operative mammograms were shown. Breast parenchymal density decreased with age and the visibility of tumours increased with age. When considered simultaneously, the effect of age (over 55 vs under 55) was greater (OR = 2.9) than the effect of density (fatty vs others) (OR = 1.5). The most common reasons for non-detection were that the lesion was overlooked (55%), diagnosed as benign (33%) or was visible only in one projection (26%). Growing density was the most common (37%) feature of those lesions originally overlooked or regarded as benign. CONCLUSIONS: Tumours are commonly visible in retrospect, but few of them exhibit specific signs of cancer, and are recognized only if they grow or otherwise change. It is not possible to differentiate most of them from normal parenchymal densities. Saarenmaa, I. (2001). Clinical Radiology56, 40-43.

Validity of radiological examinations of patients with breast cancer in different age groups in a population based study.

By studying which radiological examinations had been performed before breast cancer operations the aim was to assess, how much benefit ultrasonography (US) and fine or core needle biopsy (FNAB, CNB) gave in addition to mammography, and whether the sensitivity of these examinations varied with the age of the patient. There were 659 consecutive histologically and six cytologically verified breast cancer cases included in the study. Information on mammography, US and FNAB findings were retrieved from the original patient files and classified as malignant or benign. The sensitivity (Se) of these was compared in three age groups (26-49, 50-59 and 60-92). Seventeen (3%) tumours had operations without any radiological examination and 73 (11%) without cytological or histological verification. The sensitivity of mammography (Se=0.92) was statistically significantly higher than the sensitivity of FNAB (Se=0.85, P=0.002) or US (Se=0.86, P=0.003). The sensitivity of mammography increased with age; US sensitivity was slightly higher amongst younger than older patients; the sensitivity of FNAB did not depend on the age of the patient. The sensitivity using a cutoff level of class 5 for mammography was higher (50% typical malignant findings) than for US (45%) or FNAB (30%). Among cases with benign mammographic finding (classes 1-2), the US finding was malignant (classes 3-5) in 4% and FNAB was malignant in 7%. Mammography is a reliable method of breast examination especially for women over 50 years of age. Ultrasonography is beneficial, particularly in younger women, but it is mainly performed as a complementary examination to a mammography and therefore could not be evaluated as an independent examination. FNAB and CNB results were not related to the age of the patient.

UV light induced surface expansion phenomenon of hybrid glass thin films.

Liquid-phase deposition of sol-gel method derived hybrid glass materials is utilized for fabrication of UV-light-sensitive thin films. The hybrid glass material undergoes a surface-relief deformation when exposed to UV light. The observed deformation phenomenon is in the form of a physical expansion of the exposed areas. The UV light induced surface expansion of the hybrid glass film was used to fabricate near-sinusoidal diffraction gratings with periods of 24 microm, 18 microm, 12 microm, and 9 microm. The maximum deformation when the material was patterned as a diffraction grating was 0.685 microm. The hybrid glass material features an index of refraction of 1.52 at 632.8 microm, rms surface roughness of 2.2 +/- 0.8 microm after processing, and extinction coefficients of 1.2 x 10-3 microm-1 and 0.47 x 10-3 mm-1 at wavelengths of 633 nm and 1550 nm, respectively.

The visibility of cancer on earlier mammograms in a population-based screening programme.

The aim of this study was to examine how frequently the later-round screen-detected and interval breast cancers were visible in earlier screening mammograms by retrospective review and to compare their radiological and clinicopathological features with those diagnosed by primary screening. In a population-based mammography screening programme 63,731 women aged 50-59 years were invited and 56,158 examinations were carried out in the period 1987-1992 in the Tampere area in Finland. A total of 276 breast cancers were detected, of which 131 were diagnosed on later screening rounds or were interval cancers. A retrospective review of previous screening mammograms was carried out in 130 cases by the radiologist who diagnosed the breast cancer and thus knew the exact location of the tumour, no blinded review was carried out. 43 (33%) cancers were visible, 84 (65%) were not visible and 3 (2%) not included on the mammogram in a retrospective review. Later round screen-detected cancers were statistically significantly more often visible in earlier screening mammograms (43%) than interval cancers (19%) (P = 0.002). Tumours missed by screening mammography but which were visible on retrospective review were often histologically well-differentiated and were more often diagnosed in the subsequent screening round than by clinical diagnosis as interval cancers. If all retrospectively visible interval cancers had been diagnosed by screening 19% (10/54) of the interval cancers could have been avoided. If all retrospectively visible cancers had been diagnosed at the time of false-negative screening or assessment 65% (84/130) of all patients would have benefitted from an earlier diagnosis compared with the actual figure of 31% (41/130).

Aggressiveness of screen-detected breast cancers.

It is not clear whether screening for breast cancer works as public health policy and whether early indicators of effect predict an ultimate reduction in mortality. The malignant potentials of 248 breast cancers detected by the screening service in Finland were compared with those of 490 control cancers diagnosed before the screening service was established. Aggressiveness was assessed by DNA flow cytometry and clinical status by cancer size and node involvement. After the first screening round, the results of DNA flow cytometry were the same in cancers diagnosed by screening and in controls; these findings are consistent with the hypothesis that the biological aggressiveness of breast cancer remains constant as the cancer progresses. The proportion of patients with node-negative and small T1 cancers after the first screening was higher among the screened population than among controls, indicating earliness of diagnosis among those screened. Cancers diagnosed in the first round had a low malignant potential, as indicated by the DNA flow-cytometry and by clinical stage. Lower aggressiveness of cancers found by screening than of control cancers would indicate overdiagnosis or length-biased sampling, but not earliness of diagnosis. Screening with mammography is practised as a public-health policy in Finland. The results predict that the mortality reduction found in randomised trials can be repeated with a screening service.

Detection of thymosin beta 4 in situ in a guinea pig cerebral cortex preparation using 1H NMR spectroscopy.

In the present work we have investigated the macromolecules that contribute to the brain 1H NMR spectrum. The cerebral cortex showed distinct resonances at the uncrowded methyl- and methylene chemical shift scale of the spin-echo 1H NMR spectrum. The peaks at 1.22 and 1.40 ppm (relative to the methyl protons of N-acetyl aspartate at 2.02 ppm) arise from cerebral macromolecules without evidence for co-resonances from low molecular weight metabolites as shown by the spin-spin relaxation decays of these resonances. In addition to these NMR signals, peaks at 0.9 and 1.7 ppm from macromolecules were detected. These resonances are from proteins, and we have identified the polypeptides that contributed to the 1H NMR peaks. Two proteins that were present at concentrations of 250 and 350 micrograms/g of dryed tissue showed 1H NMR spectra that resembled the macromolecular pattern in the cerebral 1H NMR spectrum. They were identified as thymosin beta 4 and histone H1, respectively. Thymosin beta 4 was present in soluble high speed cytoplasmic fraction and in P2 pellet, whereas histone H1 was detected in nuclear enriched fraction. A chemical shift-correlated two-dimensional 1H NMR spectrum of thymosin beta 4 in vitro revealed a coupling pattern that matched the macromolecule in the cerebral cortex which we have previously noted (Kauppinen R. A., Kokko, H., and Williams, S. R. (1992) J. Neurochem. 58, 967-974). On the basis of both one- and two-dimensional NMR evidence, subcellular distribution and high concentration, we assign the 1H NMR signals at 0.9, 1.22, 1.40, and 1.7 ppm in the cerebral cortex to thymosin beta 4.

Finnish PACS project.

A Finnish PACS project has been set up with the participation and financing of 13 university and central hospitals, the Medical Board of Finland, the Hospital League of Finland, the Post and Teleoffice of Finland and the Helsinki Telephone Company with the Medical Engineering Laboratory of the Technical Research Centre of Finland as the principal investigator. The project started in December 1988 and ended in December 1990. The project focused on the functional needs for PACS. The image production, archive sizes, network capacity and workstation requirements have been studied in a big university hospital. The results show that without compression the image archive size needs to be at least 10 TB. The network capacity requirement depends very much on the interactivity requirements. In normal situations less than 1 Mbit/s is needed, if the network is configured in an efficient way. In some cases, however, the speed requirement can be of the order of 100 Mbit/s. A proposal for a hospital-wide PACS network was made. Simple calculation rules to estimate the needed capacities were also developed.

Testing of autonomic cardiovascular regulation--methodological considerations.

The different analyses of the results on autonomic nervous function tests were evaluated in 43 male and 32 female diabetic patients and in 24 male and 24 female control subjects, aged 47-67 years, all without any known heart disease. The Valsalva ratio of the first effort did not differ from the mean Valsalva ratio of three efforts. During deep breathing, heart rate variation and max/min R-R interval ratio determined from the first three breathing cycles did not differ from the respective variables calculated from six consecutive breathing cycles. Diastolic blood pressure response to isometric handgrip was greater during the third minute than during the first and the first two minutes. In conclusion, the tests for the evaluation of autonomic nervous function can be simplified without losing their diagnostic value.

DNA flow cytometric analysis indicates that many breast cancers detected in the first round of mammographic screening have a low malignant potential.

An organized mammographic screening program covered 8,690 women from selected birth cohorts (aged 50-59) in the Tampere University Central Hospital district. Forty-four breast cancer cases were detected in the first round of mammographic screening, which is 3.7 times the expected annual number of new cases in this population. To evaluate the proliferative kinetics and biological properties of these cancers, DNA flow cytometric analysis was carried out in 37 of the screen detected cancers (SDCs) using 60 clinically detected stage I-II cancers and 30 screen-detected benign lesions as reference. DNA aneuploidy was observed in 17/37 (46%) of the SDCs as compared to 41/60 (68%) in the clinical controls (p less than 0.05), while all the benign lesions were DNA-diploid. The median S-phase fraction (SPF) in the SDCs was significantly (p less than 0.001) lower (3.5%) than in the clinical controls (9.6%). Differences in SPF persisted in subgroups defined by DNA ploidy and histological type. In stage-I SDCs the median SPF value (2.5%) approached that of benign tumors (1.9%). Our epidemiological and biological data indicate that the first round of mammography predominantly detects prevalent preclinical lesions, some of which are of very low malignant potential. At present such patients may often receive too extensive treatment. DNA flow cytometry could help in the identification of cases which could be treated, for example, by breast-conserving methods.

Screening for postoperative pulmonary embolism on the basis of clinical symptomatology, routine electrocardiography and plain chest radiography.

The incidence of pulmonary embolism (PE) and the usefulness of various screening methods for its detection were studied in 108 patients undergoing elective hip surgery. Twenty patients had PE as shown by perfusion-ventilation lung scintigraphy. Six of them had symptoms of embolism. Clinical symptoms of PE, highly suggestive electrocardiographic (ECG) signs and signs in chest radiographs showed high specificity but low sensitivity with regard to PE. If the non-specific ECG signs and the symptoms and signs of deep vein thrombosis in the calves had also been taken into account, it would have been possible to identify 95% of the patients with PE. The use of all these screening tests revealed a suspicion of PE in two thirds of the patients. The simplest way to screen for postoperative PE seems to be to use a combination of the symptoms and signs of both PE and deep vein thrombosis, and to identify any tachycardia. This method gave a sensitivity of 85%.

Television tomometry in intravenous cholangiography.

Out of 93 infusion cholangiographies carried out with a remote control stand, television tomometry could be applied to the tomographic cut localization in 79 cases. The accuracy of the method was considered very good in 86% and--including the former--sufficient in 95% of the cases. With certain exceptions the method was considered suitable in the routine intravenous cholangiography. The importance of training for successful operation is emphasized.