Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Dual Data Collection”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources
PubMed1984

A multidetector alpha spectroscopy analysis system.

This document describes the attributes of an alpha spectroscopy counting and analysis system called Low Level Pulse Height Analysis (LLPHA). It was developed for multi-sample alpha spectroscopy analysis. The LLPHA system is controlled by a MIK-11/2 microcomputer with 28K of memory and uses a double-density, dual floppy disk for data storage. Detectors are interfaced to the computer via CAMAC (Computer Automated Measurement and Control) equipment. The system simultaneously supports 32 active and independent surface-barrier alpha-particle detectors. It operates with the total collection rate of up to 300 counts/sec from all active detectors, using 128 channels per spectrum and a dynamic energy range of 1.4 MeV. The system is not limited, however, to these conditions. In addition to spectral acquisition, the system provides analysis functions which include peak identification, curve-smoothing, integration, linear and logarithmic scale graphics, and corrections for base-line shift, dead-time, and background counts. These functions can be implemented while other spectra are being collected. The LLPHA system represents a highly cost-effective means of acquiring alpha spectrometric data from a large number of samples simultaneously and with rapid data analysis capability.

Alpha Particles↗
PubMed2004

Antipsychotic medication versus placebo for people with both schizophrenia and learning disability.

BACKGROUND: Antipsychotic medication is the standard treatment for people with learning disability and schizophrenia. OBJECTIVES: To determine the effects of any antipsychotic medication compared with placebo for treating people with a dual diagnosis of learning disability and schizophrenia. SEARCH STRATEGY: For this update we searched the Cochrane Schizophrenia Group's Register of trials (July 2004), relevant reference lists and sought unpublished data from pharmaceutical companies. SELECTION CRITERIA: We included all randomised clinical trials of longer than one month's duration, involving people with both schizophrenia and learning disability (a measured IQ of 70 or less) that evaluated antipsychotic medication versus placebo. DATA COLLECTION AND ANALYSIS: We reliably selected and assessed studies for methodological quality. Two reviewers, working independently, extracted data. We would have analysed dichotomous data on an intention-to-treat basis and presented continuous data with 65% completion rate. For dichotomous outcomes, our intention was to estimate a fixed effect relative risk (RR) with the 95% confidence interval (CI) together with the number needed to treat/harm (NNT/H). MAIN RESULTS: We found only one relevant randomised trial using our search method and this had to be excluded. This study included four people with a dual diagnosis of schizophrenia and learning disability, but results were only available for two of the participants. It was unclear as to which groups the other two people were allocated. In order to display the data, we would have had to have made too many assumptions about these two people and any results would be uninformative and potentially misleading. REVIEWERS' CONCLUSIONS: Using the methods described we found no randomised controlled trial evidence to guide the use of antipsychotic medication for people with both learning disability and schizophrenia. Until the urgent need for randomised controlled trials is met, clinical practice will continue to be guided by extrapolation of evidence from randomised controlled trials involving people with schizophrenia, but without learning disability, and non-randomised trials of those with learning disability and schizophrenia.

Adult↗
PubMed2000

Functional localization of a "Time Keeper" function separate from attentional resources and task strategy.

The functional neuroanatomy of time estimation has not been well-documented. This research investigated the fMRI measured brain response to an explicit, prospective time interval production (TIP) task. The study tested for the presence of brain activity reflecting a primary time keeper function, distinct from the brain systems involved either in conscious strategies to monitor time or attentional resource and other cognitive processes to accomplish the task. In the TIP task participants were given a time interval and asked to indicate when it elapsed. Two control tasks (counting forwards, backwards) were administered, in addition to a dual task format of the TIP task. Whole brain images were collected at 1.5 Tesla. Analyses (n = 6) yielded a statistical parametric map (SPM ¿z¿) reflecting time keeping and not strategy (counting, number manipulation) or attention resource utilization. Additional SPM ¿z¿s involving activation associated with the accuracy and magnitude the of time estimation response are presented. Results revealed lateral cerebellar and inferior temporal lobe activation were associated with primary time keeping. Behavioral data provided evidence that the procedures for the explicit time judgements did not occur automatically and utilized controlled processes. Activation sites associated with accuracy, magnitude, and the dual task provided indications of the other structures involved in time estimation that implemented task components related to controlled processing. The data are consistent with prior proposals that the cerebellum is a repository of codes for time processing, but also implicate temporal lobe structures for this type of time estimation task.

Adult↗
PubMed2005

Reliability of segmental accelerations measured using a new wireless gait analysis system.

The purpose of this study was to determine the inter- and intra-examiner reliability, and stride-to-stride reliability, of an accelerometer-based gait analysis system which measured 3D accelerations of the upper and lower body during self-selected slow, preferred and fast walking speeds. Eight subjects attended two testing sessions in which accelerometers were attached to the head, neck, lower trunk, and right shank. In the initial testing session, two different examiners attached the accelerometers and performed the same testing procedures. A single examiner repeated the procedure in a subsequent testing session. All data were collected using a new wireless gait analysis system, which features near real-time data transmission via a Bluetooth network. Reliability for each testing condition (4 locations, 3 directions, 3 speeds) was quantified using a waveform similarity statistic known as the coefficient of multiple determination (CMD). CMD's ranged from 0.60 to 0.98 across all test conditions and were not significantly different for inter-examiner (0.86), intra-examiner (0.87), and stride-to-stride reliability (0.86). The highest repeatability for the effect of location, direction and walking speed were for the shank segment (0.94), the vertical direction (0.91) and the fast walking speed (0.91), respectively. Overall, these results indicate that a high degree of waveform repeatability was obtained using a new gait system under test-retest conditions involving single and dual examiners. Furthermore, differences in acceleration waveform repeatability associated with the reapplication of accelerometers were small in relation to normal motor variability.

Acceleration↗
PubMed1995

Rate covariance dominates spontaneous cortical unit-pair correlograms.

Correlations between the firings of simultaneously recorded single units in auditory cortex may result from neural connectivity as well as covariation in firing rate. We present a predictor for the rate covariance part of the correlogram based on spike counts in 50 ms. Data were collected from 604 neurone pairs recorded under spontaneous conditions in primary auditory cortex of seven juvenile (30-70 days) and nine adult cats. A total of 341 pairs (56%) had a peak correlation coefficient significantly different from zero. The rate covariance comprised on average 73% of the peak correlation for single electrode pairs and 67% of that for dual electrode pairs. The remaining event correlation was significantly different from zero in 150 of the pair correlograms tested.

Action Potentials↗
PubMed2001

Evaluation of decision rules for referring women for bone densitometry by dual-energy x-ray absorptiometry.

CONTEXT: Identification of women with low bone mineral density (BMD) is an important strategy in reducing the incidence of osteoporotic fractures. However, screening all women is not recommended. OBJECTIVES: To assess the diagnostic properties of 4 decision rules--Simple Calculated Osteoporosis Risk Estimation (SCORE), Osteoporosis Risk Assessment Instrument (ORAI), Age, Body Size, No Estrogen (ABONE), and body weight less than 70 kg (weight criterion)--for selecting women for dual-energy x-ray absorptiometry (DXA) testing and to compare results with recommendations made in the National Osteoporosis Foundation (NOF) practice guidelines. DESIGN AND SETTING: Analysis of data from the Canadian Multicentre Osteoporosis Study, a population-based community sample, collected from 9 study centers across Canada between February 1996 and September 1997. PARTICIPANTS: Postmenopausal women aged 45 years or older (N = 2365) without bone disease who had DXA data for the femoral neck, data to apply selection criteria, and who were not currently taking estrogens or who had been taking hormone replacement therapy for 5 or more years. MAIN OUTCOME MEASURES: Sensitivity, specificity, and area under the receiver operating characteristic (AUROC) curve of each of the 4 decision rules and the NOF guidelines for identifying women with a BMD T score of less than -1.0 SD, less than -2.0 SD, and no more than -2.5 SD at the femoral neck, and percentages of women recommended for testing, stratified by BMD level and age. RESULTS: The percent of women with a BMD T score less than -1, less than -2, and no more than -2.5 were 68.3%, 25.4%, and 10.0%, respectively. The AUROC curves were greatest using SCORE and ORAI. The sensitivity for identifying women with a BMD T score of less than -2.0 was 93.7% (95% confidence interval [CI], 91.8%-95.6%) using the NOF guidelines and was 97.5% (95% CI, 96.3%-98.8%), 94.2% (95% CI, 92.3%-96.1%), 79.1% (95% CI, 75.9%-82.3%), and 79.6% (95% CI, 76.4%-82.8%), respectively, using the SCORE, ORAI, ABONE, and weight criterion. However, the NOF guidelines also resulted in 74.4% (95% CI, 71.3%-77.6%) of women with a normal BMD (T score of -1.0 or higher) being tested compared with 69.2% (95% CI, 65.9%-72.5%), 56.3% (95% CI, 52.7%-59.8%), 35.8% (95% CI, 32.4%-39.2%), and 38.1% (95% CI, 34.6%-41.6%), respectively, using the 4 decision rules. Assessments suggest that ABONE and weight criterion are not useful case-finding approaches. CONCLUSION: The SCORE and ORAI decision rules are better than the NOF guidelines at targeting BMD testing in high-risk patients. The acceptability of these rules in clinical practice merits further investigation given their potential effect on the use of densitometry services.

Absorptiometry, Photon↗
PubMedDate not supplied

Cross-linguistic evidence for morphological representation in the mental lexicon.

Three types of naturally occurring data address the question of morphological structure in the lexical entry: code-switching, novel forms, and speech errors. The data were collected from a wide variety of languages, including Austro-Polynesian, Semitic, and Altaic languages, and a heretofore untapped set of affixation types, including infixes, circumfixes, multiple affixes, reduplication, and nonconcatenative morphology. The data are used to argue for a dual-listing model of lexical representation (e.g., Pinker, 1991; Frauenfelder & Schreuder, 1992) over full-listing (e.g., Butterworth, 1983) and fully parsed (e.g., Taft & Forster, 1975) models. The paper posits three morphological parameters which are activated language-specifically.

Cognition↗
PubMed2003

Impact of Closed-Loop Stimulation, overdrive pacing, DDDR pacing mode on atrial tachyarrhythmia burden in Brady-Tachy Syndrome. A randomized study.

AIMS: Atrial overdrive pacing algorithms increase Atrial Pacing Percentage (APP) to reduce Atrial Tachyarrhythmia (AT) recurrences in patients with Brady-Tachy Syndrome (BTS). This study aimed to compare AT burden and APP in BTS patients treated with conventional DDDR pacing, DDD+ overdrive or Closed-Loop Stimulation (CLS). METHODS AND RESULTS: One hundred and forty-nine BTS patients were included (72 male, mean age 74+/-9), who received a dual chamber pacemaker (Philos DR or Inos 2+CLS, Biotronik GmbH, Berlin, Germany) programmed in DDD at 70min(-1). At 1-month follow-up, DDDR, DDD+ or CLS algorithms were activated according to randomization. Follow-up visits for data collection were performed at 4 and 7 months. Non parametric statistical tests (Kruskal-Wallis H-test, Dunn test, Spearman coefficient) were used to analyse not-normally-distributed samples. At 7 months, AT burden was significantly lower in CLS group (20.3+/-63.1min/day, P<0.01) compared to DDDR (56.0+/-184.0min/day) and DDD+ group (63.1+/-113.8min/day). APP was higher in CLS (89.0+/-13.2%) and in DDD+ group (97.9+/-2.7%) than in DDDR group (71.1+/-26.7%, P<0.001). The correlation found between AT burden and APP was very weak: at 7-month follow-up the Spearman coefficient was -0.29 (P=NS) in CLS, -0.52 (P<0.01) in DDD+, -0.22 (P=NS) in DDDR. CONCLUSIONS: CLS pacing was associated with a significantly lower AT burden,compared to the other pacing algorithms. Moreover APP was significantly higher in DDD+ and in CLS mode, than in DDDR. APP weakly correlated with AT burden only in DDD+ mode, though the lowest AT burden level was obtained in the CLS group where no significant correlation was found.

Aged↗
PubMed1985

Cardiac pacing practices: a survey.

A profile of permanent cardiac pacing practices in the United States during 1981 has been compiled in a survey of physicians who implant pacemakers. Approximately 5,600 physicians performed about 118,000 new primary implants at 3,670 centers. Only 17% of implantation procedures were replacements, compared with 31% in 1978. Although 90% of primary pacemakers were somewhat programmable, almost half were not reprogrammed within the first three months after implantation and 30% were never reprogrammed. Most patients (85%) were followed by trans-telephonic monitoring, 68% in conjunction with private office visits. The respondents estimated that dual-chamber pacing, accounting for 10% of implants in 1981, would increase to 37% by 1985.

Cardiac Pacing, Artificial↗
PubMed1989

Development and evaluation of a dual-pump microcomputer-based closed-loop arterial pressure control system.

Hypertension after cardiac surgery is common and is associated with increased morbidity. It is usually managed by the infusion of short acting vasodilators. The use of a closed-loop computer system to control the infusion of a vasodilator has been shown to compare favourably with manual control. We have developed a closed-loop system for the ATARI 1040ST microcomputer to control arterial pressure by the simultaneous infusion of two vasodilators. The control program is based on a proportional-integral-derivative algorithm which has been adapted to allow control of two IMED 929 infusion pumps from one RS-232 port. All communication between the user and computer is carried out with a 'mouse', thus increasing acceptability of the system to ward staff. Cardiovascular data are collected on-line from the patient monitor via a custom-built analogue to digital convertor. This system was used to study glyceryl trinitrate and sodium nitroprusside in 24 patients requiring vasodilators after cardiopulmonary bypass. The study showed that in 14 of the patients hypertension was controlled by GTN alone and 10 required supplementary SNP. We have demonstrated that this dual-pump automatic arterial pressure control system is a satisfactory and safe method of administering two vasodilators simultaneously. It is suitable for both routine clinical and research uses.

Blood Pressure↗
PubMed2000

[Multi-channel data collection and visualization system for intramyocardial electrograms].

The aim of the project was to develop a multichannel data acquisition system for the recording and visualisation of intramyocardial electrograms (IEGM) from both the spontaneously beating and the artificially paced heart. Signal processing comprises multi-step amplification, filtering (0.05-800 Hz), and AD conversion (12 Bit max. 6.25 kHz). IEGMs can be obtained either in unipolar or bipolar mode. Stimulation of the heart is achieved by an incorporated programmable dual-chamber pacemaker that can be selectively switched to the input channels. A LabView-based graphical user interface permits the programming of all system parameters via a microcontroller, and supports data acquisition and visualisation. The system can be used in animal experiments to monitor the spread of excitation across the heart, to measure propagation velocity, or to measure the impact of drugs and pathological changes on the morphology of IEGMs.

Computer Graphics↗
PubMed2005

Eradication of Helicobacter pylori for non-ulcer dyspepsia.

BACKGROUND: Helicobacter pylori (H pylori) is the main cause of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear. OBJECTIVES: To determine the effect of H pylori eradication on dyspepsia symptoms in patients with non-ulcer dyspepsia. SEARCH STRATEGY: Trials were identified through electronic searches of the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, using appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through contacts with experts in the fields of dyspepsia and with pharmaceutical companies. These searches were updated in October 2004. SELECTION CRITERIA: All parallel group randomised controlled trials (RCTs) comparing drugs to eradicate H pylori with placebo or other drugs known not to eradicate H pylori for patients with non-ulcer dyspepsia. DATA COLLECTION AND ANALYSIS: Data were collected on individual and global dyspeptic symptom scores, quality of life measures and adverse effects. Dyspepsia outcomes were dichotomised into minimal/resolved versus same/worse symptoms. MAIN RESULTS: Seventeen randomised controlled trials were included in the systematic review. Fourteen trials compared antisecretory dual or triple therapy with placebo antibiotics +/- antisecretory therapy, and evaluated dyspepsia at 3-12 months. Thirteen of these trials gave results as dichotomous outcomes evaluating 3186 patients and there was no significant heterogeneity between the studies. There was a 8% relative risk reduction in the H pylori eradication group (95% CI = 3% to 12%) compared to placebo. The number needed to treat to cure one case of dyspepsia = 18 (95% CI = 12 to 48). A further three trials compared Bismuth based H pylori eradication with an alternative pharmacological agent. These trials were smaller and had a shorter follow-up but suggested H pylori eradication was more effective than either H2 receptor antagonists or sucralfate in treating non-ulcer dyspepsia. AUTHORS' CONCLUSIONS: H pylori eradication therapy has a small but statistically significant effect in H pylori positive non-ulcer dyspepsia. An economic model suggests this modest benefit may still be cost-effective but more research is needed.

Adult↗
PubMed1992

Anal sphincter biofeedback relaxation treatment for women with intractable constipation symptoms.

Some constipated women have difficulty relaxing the striated muscles of the anal sphincters, sometimes called anismus. This study was developed to provide a biofeedback-based relaxation treatment to teach these patients to relax the "voluntary" anal sphincter muscle in order to assess whether this treatment would be effective in reducing symptomatology. Seven constipated patients who were unresponsive to a high-fiber diet and required persistent laxative dosing to achieve regular bowel frequency were studied. A dual-therapy approach, in which patients were taught to relax the anal sphincter muscles via biofeedback from a manometric anal sphincter probe, was used. Concurrently, patients were instructed in general biofeedback-relaxation techniques. All were treated as outpatients. Complete data were collected on five patients, one patient discontinued therapy, and one patient moved after treatment was completed. Stool frequency improved from a mean of 1.9 per week to a mean of 4.9 per week in six patients (P less than 0.05). In the five patients who completed the entire protocol, pain and bloating symptom levels were compared before and after treatment. Abdominal pain grade was reduced from 12.8 per week to a mean of 4.4 per week (P less than 0.05), and bloating was reduced from a mean of 14.3 per week to a mean of 6.0 per week (P less than 0.06). Follow-up of 2 to 4.5 years posttherapy showed continued improvement in bowel function and abdominal symptomatology. This treatment appears to be effective in improving stool frequency and in reducing the associated abdominal pain and bloating symptoms in constipated women with anismus.

Abdominal Pain↗
PubMed2005

Body size from birth to adulthood and bone mineral content and density at 31 years of age: results from the northern Finland 1966 birth cohort study.

The purpose of this study was to evaluate the association between body size from birth to adulthood and bone mineral content (BMC) and bone mineral density (BMD) at the age of 31 years in a longitudinal study of the Northern Finland birth cohort for 1966. Data were collected at birth, 1, 14, and 31 years. This analysis was restricted to a subsample of individuals (n =1,099) for whom the BMC (g) and BMD measurements (g/cm(2)) were performed on the distal and ultradistal radius by dual-energy X-ray absorptiometry (DXA) at the age of 31 years. Determinants of low BMC and BMD were analyzed using multivariate logistic regression. Growth retardation at birth, being underweight (BMI < or =20.0 kg/m(2)) at 31 years, and having a low calcium intake at 31 years were associated independently with low BMD at 31 years. Additionally, the proportion of subjects with low BMD was higher among those who had low standardized body weight (< or =1 SD) both at birth and at 14 years, and both at 14 and 31 years. Body weight at 31 years was the strongest associating factor of BCM at 31 years. Growth retardation at birth has long-lasting effects on adult bone mineral content and density of the distal and ultradistal radius independently of later body size, although adult body weight seems to be a most important determinant of BMC at the age of 31 years. Thinness and a low calcium intake are associated with low bone mineral content and density at 31 years of age. Further studies are needed to evaluate if these groups are at increased risk of osteoporosis in old age.

Absorptiometry, Photon↗
PubMed1991

Why reinvent the wheel? The tumor registry as a radiation oncology quality assurance data base for hospitals.

The Tumor Registry wheel has a sound, tested, basic design and could serve the dual purpose of a Radiation Oncology QADB. Many of the issues raised by Williamson regarding a QADB have already been addressed and tested by the Tumor Registry and commercially available Tumor Registry software. Registry personnel are trained in this type of data collection, coding and reporting. You may already have a Tumor Registry that has the capacity to provide this service to your department with the addition of only minimal efforts. If your Tumor Registry only collects minimal data now, it is probably because it has only minimal support and use. If you choose to utilize the Tumor Registry for your Radiation Oncology QADB, your department can provide additional support in many ways in return for the services provided to you. Maximum support can be given by assuming full responsibility and locating the registry in the Radiation Oncology cost center. As mentioned earlier, many Radiation Oncologists have recognized the variety of benefits derived from this situation. Other forms of assistance might include financial support for the upgrading of computer hardware and software required to facilitate these new needs, or by providing additional secretarial personnel, possibly on a part-time basis. Support voiced to the administration from the Radiation Oncologist for the need and use of the Tumor Registry can be helpful in getting approval for upgrading tumor registry equipment or obtaining adequate personnel. Developing a symbiotic relationship between these two departments can strengthen the entire Cancer Program as well as each of the individual departments.(ABSTRACT TRUNCATED AT 250 WORDS)

Accreditation↗
PubMed2003

Body composition in the elderly: the influence of nutritional factors and physical activity.

BACKGROUND: Controversy exists regarding the relative contribution of diet and exercise to body composition. Few studies have examined these associations in the elderly, where changes occur in the body fat to muscle ratio. OBJECTIVE: The primary objective of this paper is to determine whether energy intake or physical activity are associated with body composition. Secondly, to investigate whether specific macronutrients are associated with fat or lean tissue. DESIGN: Data (n= 1404) for this cross-sectional analysis were collected from a population-based sub-sample of elderly enrollees in the Cardiovascular Health Study (CHS). Dietary intake and physical activity were assessed by questionnaires. Body composition was measured by Dual Energy X-ray Absorptiometry (DEXA). Linear regression models were used to assess the associations of diet and activity with body composition. RESULTS: Total energy intake was not associated with any of the body composition measures. Higher dietary saturated fat was associated with higher percent body mass as fat and trunk fat in both sexes (p<0.01), and in men other dietary fats were associated with body fat. In women, distance walked was inversely associated with fat masses even after adjustment for pace of walking. In both sexes, faster pace of walking was associated with lower body and fat mass (p<0.01). Lean muscle mass was not associated with physical activity or dietary intakes. CONCLUSION: Physical activity and dietary fat intake in this the elderly population were more closely associated with body fat mass than was total energy intake.

Absorptiometry, Photon↗
PubMed2006

Eradication of Helicobacter pylori for non-ulcer dyspepsia.

BACKGROUND: Helicobacter pylori (H pylori) is the main cause of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear. OBJECTIVES: To determine the effect of H pylori eradication on dyspepsia symptoms in patients with non-ulcer dyspepsia. SEARCH STRATEGY: Trials were identified through electronic searches of the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, using appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through contacts with experts in the fields of dyspepsia and with pharmaceutical companies. SELECTION CRITERIA: All parallel group randomised controlled trials (RCTs) comparing drugs to eradicate H pylori with placebo or other drugs known not to eradicate H pylori for patients with non-ulcer dyspepsia. DATA COLLECTION AND ANALYSIS: Data were collected on individual and global dyspeptic symptom scores, quality of life measures and adverse effects. Dyspepsia outcomes were dichotomised into minimal/resolved versus same/worse symptoms. MAIN RESULTS: Twenty one randomised controlled trials were included in the systematic review. Eighteen trials compared antisecretory dual or triple therapy with placebo antibiotics +/- antisecretory therapy, and evaluated dyspepsia at 3-12 months. Seventeen of these trials gave results as dichotomous outcomes evaluating 3566 patients and there was no significant heterogeneity between the studies. There was a 10% relative risk reduction in the H pylori eradication group (95% CI = 6% to 14%) compared to placebo. The number needed to treat to cure one case of dyspepsia = 14 (95% CI = 10 to 25). A further three trials compared Bismuth based H pylori eradication with an alternative pharmacological agent. These trials were smaller and had a shorter follow-up but suggested H pylori eradication was more effective than either H2 receptor antagonists or sucralfate in treating non-ulcer dyspepsia. AUTHORS' CONCLUSIONS: H pylori eradication therapy has a small but statistically significant effect in H pylori positive non-ulcer dyspepsia. An economic model suggests this modest benefit may still be cost-effective but more research is needed.

Adult↗
PubMed1996

Decomposition of inflow and blood oxygen level-dependent (BOLD) effects with dual-echo spiral gradient-recalled echo (GRE) fMRI.

Image contrast with gradient-recalled echo sequences (GRE) used for fMRI can have both blood oxygen level-dependent (BOLD) and inflow components, and the latter is often undesirable. A dual-echo technique can be used to differentiate these mechanisms, because modulation of signal from inflow is common to both echoes, whereas susceptibility and diffusion-related signal losses are larger in the second echo. An efficient dual-echo interleaved spiral sequence was developed for use with a conventional scanner. It uses a k-space trajectory that spirals out from the origin while the first echo is collected, then spirals back in while collecting the second echo. Decomposition of the data provides separate images of the inflow and T2-weighted components. Results demonstrate the decomposition with phantom experiments and with photic stimulation in normal volunteers.

Brain Mapping↗