SEARCH · PubMed Health

Results for “virtual intervention”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 325 records · Page 18Linked to original sources

PubMed2000

A novel mechatronic tool for computer-assisted arthroscopy.

This paper describes a novel mechatronic tool for arthroscopy, which is at the same time a smart tool for traditional arthroscopy and the main component of a system for computer-assisted arthroscopy. The mechatronic arthroscope has a cable-actuated servomotor-driven multi-joint mechanical structure, is equipped with a position sensor measuring the orientation of the tip and with a force sensor detecting possible contact with delicate tissues in the knee, and incorporates an embedded microcontroller for sensor signal processing, motor driving and interfacing with the surgeon and/or the system control unit. When used manually, the mechatronic arthroscope enhances the surgeon's capabilities by enabling him/her to easily control tip motion and to prevent undesired contacts. When the tool is integrated in a complete system for computer-assisted arthroscopy, the trajectory of the arthroscope is reconstructed in real time by an optical tracking system using infrared emitters located in the handle, providing advantages in terms of improved intervention accuracy. The computer-assisted arthroscopy system comprises an image processing module for segmentation and three-dimensional reconstruction of preoperative computer tomography or magnetic resonance images, a registration module for measuring the position of the knee joint, tracking the trajectory of the operating tools, and matching preoperative and intra-operative images, and a human-machine interface that displays the enhanced reality scenario and data from the mechatronic arthroscope in a friendly and intuitive manner. By integrating preoperative and intra-operative images and information provided by the mechatronic arthroscope, the system allows virtual navigation in the knee joint during the planning phase and computer guidance by augmented reality during the intervention. This paper describes in detail the characteristics of the mechatronic arthroscope and of the system for computer-assisted arthroscopy and discusses experimental results obtained with a preliminary version of the tool and of the system.

Arthroscopes↗

PubMed2004

[Virtual bronchoscopy for follow-up investigation of main airway stenoses].

The aim of the study was to compare the utility and effectivity of conventional and virtual bronchoscopy in the follow up of patients with main airway stenosis. 23 patients with trachea or main bronchi stenosis were enrolled in the study. The causes of the stenosis were malignant or benign tumor, struma and stent. The stenoses were evaluated before and after the different interventions (i.e. mechanical dilatation, laser photocoagulation, stent implantation, radiotherapy, chemotherapy or surgical resection.) The mean time between the first and second endoscopic and virtual bronchoscopic examinations was 140 days. The authors found good correlation between bronchofiberoscopy and virtual bronchoscopy findings. The data of virtual bronchoscopy were more exact. Based on this study the virtual bronchocopy can replace the traditional invasive method to follow-up patients with main airway stenosis.

Adult↗

PubMed2005

Angiotensin-converting enzyme inhibition intervention in elderly persons: effects on body composition and physical performance.

The disablement process is often accompanied by sarcopenia or muscle loss, which is associated with virtually all identified disability risk factors. Clinically, the association between body composition and physical performance has been documented by several studies. However, loss of strength is greater than loss of muscle mass with age implying that the quality of remaining muscle may be reduced. Although there are limited data explaining potential physiological mechanisms that contribute to muscle quality, sarcopenia is frequently associated with fat accumulation, and the percentage of body fat increases with age even if weight does not. However, the relationship between fat and muscle function may not be linear, suggesting that there may be an optimal ratio of lean to fat mass for physical function. There are no definitive pharmacological interventions proven to prevent decline in physical function either by modulating body composition or by other means. One exception may be angiotensin-converting enzyme inhibitors (ACEIs). ACE is an important component of the renin-angiotensin system, the central hormonal regulator of blood pressure. Recent evidence suggests that ACEIs may improve physical function by means of direct effects on body composition in older persons, rather than through its blood-pressure-lowering effects. Clinical and genetic studies in humans and experimental evidence in animals suggest that modulation of the renin-angiotensin system is associated with metabolic and biochemical changes in skeletal muscle and fat, changes that are associated with declining physical function. ACEIs may modulate this process through a variety of molecular mechanisms including their influence on oxidative stress and on metabolic and inflammation pathways. This review describes potential biological mechanisms of ACE inhibition and its contribution to declining physical performance and changing body composition. Promising pharmacoepidemiological studies and experimental evidence in animals suggest that there are appropriate models in which to study this effect.

Aged↗

PubMed2004

Virtual interaction in cognitive neuropsychology.

Several recent studies have investigated whether knowledge representation turns possible within virtual reality simulated environments. According to these affirmative results different clinical applications were developed in psychology. Among these applications virtual reality seems to have a specific role in assessment and treatment of neuropsychological diseases. This chapter will firstly investigate possibilities and challenges carried from virtual-reality-based neuropsychological applications focusing both on patient's and therapist's point of view. Afterward it will provide a survey of research and intervention application examples. More in detail a clear explanation of contribution goals will be discussed, in order to place research and applied works within a cognitive neuroscience frame of reference, according with their usefulness and effectiveness in clinical treatment. Fulfilling these objectives neuropsychological virtual reality approaches in memory, motor abilities, executive functions and spatial representation will be shown.

Cognitive Behavioral Therapy↗

PubMed2005

Developing a relativities approach to valuing the prevention of non-fatal work-related accidents and ill health.

The aim of the current explorative study is to define and test a process for the valuation of the benefits associated with the prevention of non-fatal work-related accidents and ill health. A relativities approach is adopted, and monetary values for the prevention of three forms of work-related illness are estimated. The approach involves describing relevant attributes of alternative events (accidents or occurrences of ill health), their causes, the characteristics of the relevant working population, and the number of events that are avoidable, and asking respondents to make pair wise choices between alternatives options for prevention. Indirect monetary valuations are obtained against a peg event for which a reliable valuation exists (road deaths).A series of discussion groups were held to identify relevant factors affecting potential valuations and to test the presentation of information. The predicted magnitude of responses for three-case study events (and road deaths) was estimated in a pilot study. These preliminary stages informed the final survey instrument that described five attributes in addition to a statement of the event and occupation, and the likely intervention effect, which was administered by post. Based on a small sample, the results show that virtually all respondents passed the inserted consistency test. The median respondent altered their choice according to the number of events avoided for all three comparisons, such that the estimated valuations appear sensible. Potential amendments are suggested, but the general relativities approach warrants further investigation for the valuation of non-fatal work-related accidents and ill health.

Accidents, Occupational↗

PubMed1991

Asthma in the emergency department: impact of a protocol on optimizing therapy.

The objective of this study was to evaluate the impact of a simple educational intervention on the prescribing habits of internal medicine residents in the treatment of acute asthma in a busy emergency department (ED). Prescribing habits for 16 residents were documented for 4 months. The first 2 months served as a control period during which eight residents managed asthma patients without the benefit of any specific educational intervention beyond standard department protocols. A total of 129 patients treated by the residents during this initial phase were assessed. During the second 2-month period, a 10-minute verbal presentation and explicit written treatment protocol were provided to another eight residents, and their treatment of 83 patients was covertly evaluated. Increased prescribing of desired therapy was significantly improved in every area except that of prescribing an inhaled steroid metered dose inhaler for use as a discharge medication. The 10-minute verbal presentation given in conjunction with a three-page handout was found to be highly effective for eliciting improvement in treatment practices during short clinical rotations. The duration of this effect beyond each rotation is unknown. This educational intervention should be presented by the ED medical director, clinical pharmacist, or other appropriate clinician in virtually any ED as quality of patient care can be dramatically improved.

Acute Disease↗

PubMed1991

The dorsolateral, suboccipital, transcondylar approach to the lower clivus and anterior portion of the craniocervical junction.

The authors review their experience with a dorsolateral approach to the anterior rim of the foramen magnum and adjacent region. The operative technique includes exposure of the vertebral artery at C1, partial resection of the occipital condyle and lateral atlantal mass, and extradural drilling of the jugular tubercle. This approach has been applied in six patients who harbored intradural space-occupying lesions located ventral to the lower brain stem. Excision of the neoplasm was virtually total in all but one patient, in whom biopsy was the primary goal of the intervention. No morbidity and no mortality were associated with this approach. The main advantage of the dorsolateral, suboccipital, transcondylar route is the direct view it offers to the anterior rim of the foramen magnum without requiring brain stem retraction.

Adult↗

PubMed1992

Correlates of obesity in young black and white women: the CARDIA Study.

OBJECTIVES: Although differences in obesity between Blacks and Whites are well documented in adult women, less information is available on potential correlates of these differences, especially in young adults. METHODS: The association between behavioral and demographic factors and body size was assessed in 2801 Black and White women aged 18 to 30 years. RESULTS: Black women had significantly higher age-adjusted mean body mass index and subscapular skinfold thickness than did White women. Obesity had different associations with age and education across racial groups. A positive relationship between age and obesity was seen in Black women but not in White women, whereas a negative association between education and body size was noted only in White women. Potential contributing factors to the increased prevalence of obesity in Black women include a more sedentary lifestyle, higher energy intake, earlier menarche, and earlier age at first childbirth. CONCLUSIONS: The difference in obesity across race could not be explained completely by these factors, since within virtually all strata, Black women had higher body mass indexes. Further investigation is needed to develop interventional strategies to prevent or reduce excess levels of obesity in Black women.

Adolescent↗

PubMed2000

[3D spiral computerized tomography in the reconstructive treatment of malignant maxillofacial tumors].

PURPOSE: To investigate the role of Helical CT and the usefulness of three-dimensional (3D) imaging for preoperative planning and follow-up of reconstructive maxillofacial surgery with alloplastic material in neoplastic disease involving this region. MATERIAL AND METHODS: From 1996 to 1999 eleven patients were examined with Helical CT and 3D images for planning of maxillofacial plastic and reconstructive surgery for advanced cancer of this anatomically complex region. A 3D-modulated titanium mesh (100%) or micronets was used to rebuild the anterior surface of maxillary bone and the orbital floor. The mesh was cut to the appropriate size and shape and curved where necessary. Within the residual sinusal cavity a siliconed filling was used surmounting an acrylic prosthesis with dental arch to rebuild the palate. A rehydrated bovine pericardium was affixed and moduled on the borders in two cases only. Three-dimensionally reconstructed CT images were obtained preoperatively and at least 6 months postoperatively in all patients. The images were generated on a computer workstation using the shaded surface display (SSD) software with threshold values ranging 425 to 630 HU, and a more closed window for the imaging of titanium mesh/bone interface in the postsurgical follow-up. RESULTS: We always obtained an excellent complete spatial depiction of maxillofacial region both before and after surgery, with no artefacts so important as to affect the 3D reconstruction process and the image quality. Together with the head-neck surgical team we could work for preoperative planning through CT scans by different 3D points of view. The 3D reconstructed follow-up scans showed good filling of the defect in the area where the titanium mesh had been used. Then efficacious bone modelling and good biocompatibility of the alloplastic material were seen in all patients, with no inflammatory reactions. CONCLUSIONS: Titanium is a well-known material, which is widely used for cranioplasty. It is a radiolucent, nonferrous metal of low atomic number that allows very clear CT and MR images to be obtained. Further Ti features are strength, biocompatibility and easy handling. 3D Helical CT scan has proved to be the most complete and accurate imaging technique for reconstructive plastic surgery with alloplastic material in advanced maxillofacial cancer, also considering the anatomic and functional complexity of this area. The prospect is provided to identify virtual 3D presurgical ablation planes. These may allow the surgeon to improve plastic reconstruction and shorten intervention time.

Acrylic Resins↗

PubMed1983

Disintegration of renal and ureteral calculi with ultrasound.

Disintegration of stones with ultrasound under endoscopic control has eliminated size as the major limitation to percutaneous and transureteral extraction of calculi from the upper urinary tract. With virtually no side effects to soft tissues, approximately 60 per cent of all renal calculi requiring intervention can be managed percutaneously instead of by open surgery.

Cystoscopy↗

PubMed1997

Extensive mesenteric inflammatory veno-occlusive disease of unknown etiology after primary cytomegalovirus infection: first case.

We report a young man who, shortly after a primary cytomegalovirus infection, presented with signs of intestinal ischemia requiring surgical intervention. The resected specimen of small bowel showed striking features of extensive phlebitis and venulitis affecting virtually all of the veins of the small intestine and mesentery. Although he had had a recent primary cytomegalovirus viremia, we could not identify any evidence of cytomegalovirus in the small bowel. He was not infected with HIV. The entity we describe is different from the recently reported mesenteric inflammatory veno-occlusive disease. The clinicopathologic entity represented by our patient's disease was heretofore unrecognized.

Adult↗

PubMed1997

Dietary fat reduction achieved by increasing consumption of a starchy food--an intervention study.

OBJECTIVE: To test t he hypothesis that increased consumption of foods in rich in starch, such as breakfast cereals, will enable a substantial reduction in the percentage dietary energy derived from fat. DESIGN: Parallel experimental design, with matched subjects allocated randomly to an intervention or a control group. SETTING: Free-living subjects (mean age 20 y), undergraduate students at a college for higher education. SUBJECTS: Sixty-two enrolled, 59 completed the study; 7 d weighed intakes at baseline, 4 weeks and 12 weeks. INTERVENTION: The intervention group were required to eat 60 g breakfast cereal daily with semi-skimmed milk. Pre-weighed portions of three types of cereal were distributed without charge at the beginning of each week of the study; subjects were reimbursed for the cost of milk used. No other dietary advice was given. RESULTS: At baseline, total energy intake and percentage energy from macronutrients was very similar in both the intervention and control group. After four weeks of intervention there was a significant reduction in % energy from fat (-5.4%) in the experimental group, maintained at the 12 weeks follow-up. There was a corresponding rise in energy from CHO: a significant increase of 5.5% after four weeks had reached 6.5% by 12 weeks. Total energy remained virtually unchanged, indicating a replacement of fat energy by carbohydrate energy. These changes were not found in the control group. CONCLUSIONS: A simple dietary intervention to increase consumption of breakfast cereal led to a 5% reduction in % dietary fat energy, with a beneficial effect on micronutrient intakes. The results support the case for positive advice to increase consumption of complex carbohydrate, as a strategy for dietary fat reduction in the wider population.

Adolescent↗

PubMed1990

Comparison between force-velocity and end-systolic pressure-volume characterization of intrinsic LV function.

We reanalyzed experiments in in situ hearts of 16 open-chest anesthetized dogs, in which two different loading interventions were performed, i.e., an occlusion of the descending aorta (InP) and a rapid volume infusion (InV). Previous studies had demonstrated that the end-systolic elastance (Ees) of the InP was substantially larger than the Ees of the InV suggesting either a load dependency of Ees as such, or an increase in contractility during InP. The data were reanalyzed in the light of the muscular pump concept by plotting peak normalized velocity of circumferential shortening versus a global representative force approximating the left ventricle by a sphere. In all but one experiment the points of the two interventions are located on a single relationship over a very broad range of forces (from 397 to 2,461 g between the control states of experiments and from 602 to 3,278 g difference between control and highest load within experiments). The virtual independence of the force-velocity relation (FVR) and the dependence of the end-systolic pressure-volume relation (ESPVR) on the type of loading intervention can be ascribed to the fact that the former is assessed early during ejection and is therefore less influenced by shortening deactivation and internal resistance than the ESPVR. We conclude that the FVR offers a more consistent characterization of intrinsic LV function than the ESPVR.

Animals↗

PubMed1997

Intraoperative guidance in maxillofacial and craniofacial surgery.

The authors' experiences with intraoperative computer assisted guidance in interventions in oromaxillofacial and craniofacial surgery are reported. The guidance system SPOCS (Surgical Planning and Orientation Computer Systems, Aesculap, Germany) consists of an infrared light emitting system of diodes and camera, an imaging workstation and assorted freehand instruments. The software is an updated version of the well-known Viewing Wand software (ISG Technologies, Canada). In tests on phantoms, the system proved a mean accuracy of less than 1.5 mm. Within the last 15 clinical tests, the system has achieved an accuracy better than 3 mm which, at the moment, the authors estimate to be sufficient to proceed with its clinical evaluation. Using bone screws to register the patient's position, an accuracy in the range of less than 2 mm in relation to bony reference points has been achieved. By visualizing the tip of the instrument in real time, this technique allows surgical interventions, even in anatomically complicated situations, without endangering vital neighbouring structures. The 'offset' function of the software, by which the surgeon can elongate the tip of the instrument virtually, allows the surgeon to analyse structures before they are penetrated by the instrument as in a 'look ahead' operation. The authors expect computer assisted simulation and guidance systems to improve surgical quality and reduce the risks associated with surgical interventions.

Adolescent↗

PubMed2004

Benefits and costs of interventions to improve breast cancer outcomes in African American women.

PURPOSE: Historically, African American women have experienced higher breast cancer mortality than white women, despite lower incidence. Our objective was to evaluate whether costs of increasing rates of screening or application of intensive treatment will be off-set by survival benefits for African American women. METHODS: We use a stochastic simulation model of the natural history of breast cancer to evaluate the incremental societal costs and benefits of status quo versus targeted biennial screening or treatment improvements among African Americans 40 years of age and older. Main outcome measures were number of mammograms, stage, all-cause mortality, and discounted costs per life year saved (LYS). RESULTS: At the current screening rate of 76%, there is little incremental benefit associated with further increasing screening, and the costs are high: 124,053 US dollars and 124,217 US dollars per LYS for lay health worker and patient reminder interventions, respectively, compared with the status quo. Using reminders would cost 51,537 US dollars per LYS if targeted to virtually unscreened women or 78,130 US dollars per LYS if targeted to women with a two-fold increase in baseline risk. If all patients received the most intensive treatment recommended, costs increase but deaths decrease, for a cost of 52,678 US dollars per LYS. Investments of up to 6,000 US dollars per breast cancer patient could be used to enhance treatment and still yield cost-effectiveness ratios of less than 75,000 US dollars per LYS. CONCLUSION: Except in pockets of unscreened or high-risk women, further investments in interventions to increase screening are unlikely to be an efficient use of resources. Ensuring that African American women receive intensive treatment seems to be the most cost-effective approach to decreasing the disproportionate mortality experienced by this population.

Adult↗

PubMed2005

Methodological considerations and approach to cross-technique comparisons using in vivo coronary plaque characterization based on intravascular ultrasound radiofrequency data analysis: insights from the Integrated Biomarker and Imaging Study (IBIS).

Grey scale intravascular ultrasound (IVUS) is a valuable clinical tool to assess the extent and severity of coronary atheroma. However, it cannot reliably identify plaques with a high-risk of future clinical events. Serial IVUS studies to assess the progression and/or regression of atherosclerotic plaques demonstrated only modest effects, of pharmacological intervention on plaque burden, even when clinical efficacy is documented. Spectral analysis of radiofrequency ultrasound data (IVUS-virtual histology (IVUS-VH), Volcano Therapeutics, Rancho Cordova, CA) has the potential to characterize accurately plaque composition. The Integrated Biomarker and Imaging Study (IBIS) evaluated both invasive and non-invasive imaging techniques along with the assessment of novel biomarkers to characterize sub-clinical atherosclerosis. IVUS-VH was not included at the start of the IBIS protocol. The purpose of this paper is to describe the methodology we used to obtain and analyse IVUS-VH images and the approach to cross-correlations with the other techniques.

Biomarkers↗

PubMed1999

Improving cognitive function after brain injury: the use of exercise and virtual reality.

OBJECTIVE: To assess the impact of exercise and virtual reality (VR) on the cognitive rehabilitation of persons with traumatic brain injury (TBI). DESIGN: Before-after trial assessed cognitive function after a 4-week intervention program. A random allocation crossover assessed changes in reaction and movement times after a single bout of VR exercise and a no-exercise control condition. SETTING: Brain injury rehabilitation unit in Edinburgh, Scotland. PATIENTS: (1) Four-week intervention: a consecutive sample of 13 suitable TBI adults were compared to control populations (n > 25) of previous TBI patients of similar age, severity, and time postinjury. (2) Single-bout intervention: a consecutive sample of 13 suitable adults with moderate TBI, 6.29 to 202.86 weeks postinjury. INTERVENTION: Nonimmersive VR exercise. MAIN OUTCOME MEASURES: (1) Tests of attention, information processing, learning, and memory. (2) Reaction and movement times. RESULTS: After the 4-week intervention patients performed significantly better than controls on the digit symbol (p < .01). verbal (p < .01), and visual learning tasks (p < .05). Significant improvements in reaction times (p < .01) and movement times (p < .05) were gained following a single bout of VR exercise. CONCLUSION: Exercising in a virtual environment offers the potential for significant gains in cognitive function.

Adolescent↗

PubMed2004

The impact of teleconsultations at a referential centre on the management of pulmonary patients.

Teleconsultation services at referential centres are an important area of telemedicine development. The implementation of such scenarios brings high-level competencies to peripheral hospitals through telecommunication links. Pulmonary teleconsultations were one of the key aspects of Krakow Centre of Telemedicine (KCT) activities conducted in 2002-2003. The role of the referential centre for respiratory medicine was played by the Division of Interventional Pulmonology, Jagiellonian University Medical College. Peripheral centres were pulmonary wards situated in local hospitals or policlinics located 20-80 km from Krakow. These hospitals were equipped with PC-based telemedical workstations and ISDN lines (256 kbps). Dedicated software (Telenegatoscope) was used for real-time discussions among physicians on medical images (X-rays, CTs) sent from peripheral centres to the referential centre. Images inserted in light boxes were cropped at peripheral centres with a high-resolution digital camera. During the pilot phase, about 40 pulmonary patients were referred via telemedical links to the University Hospital. The frequency of soliciting a second opinion at the referential centre was analyzed for each main type of disease. Top positions are currently occupied by diagnoses of lung cancer, pleural fluid of unknown origin, asbestosis and tuberculosis. About 70% of the patients referred for virtual consultation were admitted for further diagnostics and treatment in an ambulatory or inpatient mode at the Division of Interventional Pulmonology. The review of teleconsultations results indicates that teleconferencing contacts, even if conducted through relatively limited bandwidth, may bring considerable benefits to patients requiring complex diagnostic and sophisticated, procedures available at the referential university hospital.

Community Health Services↗