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At least 271 records · Page 15Linked to original sources
PubMed2001

Fine motor assessment in chronic wrist pain: the role of adapted motor control.

OBJECTIVE: To show whether a difference in fine motor control exists between patients with chronic, undiagnosed wrist pain (CUWP) and healthy controls. Furthermore, a method to assess fine motor function of the wrist is evaluated. DESIGN: A case-control study. SETTING: The Academic Medical Center in Amsterdam, the Netherlands. SUBJECTS: Twenty-seven CUWP patients were compared with 50 healthy control subjects. INTERVENTIONS: Subjects performed horizontal stroke patterns on a digital writing tablet connected to a computer. The control subjects were tested twice to obtain test-retest reliability. A visual analogue scale was used to assess subjective pain. MAIN OUTCOME MEASURES: Fluency of movement and average velocity were measured. Intraclass correlation, ANOVA repeated measures statistics and Pearson correlation were calculated. RESULTS: There is a significant difference in fluency of motion between patients and controls, possibly due to a disturbed motor control, since there is no relationship between pain and test score, nor do CUWP patients have any abnormality in the wrist that can explain the disturbance in motor function. The test method is reliable (ICC = 0.78) and valid. CONCLUSIONS: The disturbed fine motor control in CUWP patients is suggested to maintain chronic wrist pain through 'strain injury, causing' pain evasive adaptation of the motor control system. This might lead to new perspectives regarding treatment of CUWP patients.

Adaptation, Physiological↗
PubMed2006

Toe-tourniquet syndrome: a diagnostic dilemma!

Strangulation of digits, the 'toe-tourniquet' syndrome needs prompt intervention as failure to recognise the condition can lead to ischaemia and loss of the appendage. It is a common condition though relatively under reported. Those who deal with children more frequently are aware of the condition but this is not the case for all medical practitioners and hence the diagnostic dilemma for accidental injury or child abuse arises. We report this case to increase physician awareness of the syndrome, to highlight the importance of early release of the tourniquet and to avoid misinterpretation of the condition as child abuse.

Constriction, Pathologic↗
PubMed1998

[Coronary intervention at a general hospital in the State of Piauí, Brazil].

PURPOSE: To evaluate retrospectively success and complication rates of coronary interventions performed in a general hospital with no digital equipment in the State of Piauí with a small annual number of procedures. METHODS: From August/91 to January/98, 122 patients underwent 146 procedures using a fluoroscope with camera and TV monitor of 525 lines. The variables analyzed included the initial success of procedures (residual stenosis less than fifty percent and TIMI III flow) and more serious complications (acute occlusion, infarcts, emergency surgeries and death). The clinical data and the morphological characteristics of the lesions (ACC/AHA Task Force) were also analyzed. RESULTS: Eighty five percent of the patients presented with an acute ischemic syndrome (acute myocardial infarction, post infarction angina, rest angina), 5% were in cardiogenic shock and 88% had type B lesions. The initial success rate was 93% while the more serious complications occurred in 3.5% of the cases. CONCLUSION: In spite of the small annual procedural volume and the use of conventional equipment, the initial success rate in our institution was excellent in a diverse and complex patient population while the complication rates were similar to that of the literature.

Adult↗
PubMed1995

Comparison of three methods of measurement of pulmonary artery catheter readings in critically ill patients.

BACKGROUND: Pulmonary artery catheter readings are critical for clinical decision making and therapeutic intervention in critically ill patients. Research data of digital display versus graphic strip chart recording of hemodynamic pressures during spontaneous breathing and mechanical ventilation are inconclusive. OBJECTIVES: To compare three methods of measurement of hemodynamic pressure readings from the pulmonary artery catheter in critically ill patients during mechanical ventilation and spontaneous breathing. METHODS: A nonrandomized, repeated-measures design was used to compare hemodynamic pressures (right atrial, systolic, diastolic, and wedge pressures) from the pulmonary artery catheter in cardiovascular patients during mechanical ventilation (n = 25) and again during spontaneous breathing (n = 19). RESULTS: Using repeated measures analysis of variance, statistically significant differences were noted in the pulmonary artery diastolic, wedge, and right atrial pressure during mechanical ventilation. During spontaneous breathing, significant differences occurred in pulmonary artery systolic and wedge pressures only. No statistically significant difference occurred in the systolic pressure during mechanical ventilation, or the pulmonary artery diastolic and right atrial pressures during spontaneous breathing. CONCLUSIONS: The results of this study indicate that graphic recording is the most reliable means of measuring hemodynamic pressure at end-expiration. Further research is needed to validate these findings with other models of monitoring equipment and other patient populations.

Adult↗
PubMed1993

Accuracy of electronic digital calipers compared with quantitative angiography in measuring coronary arterial diameter.

BACKGROUND: Quantitative angiography is the accepted method for measuring coronary luminal diameter. Electronic digital calipers have been used to assess arterial diameters in vasomotor function studies and after interventional procedures. However, careful validation of calipers against quantitative angiography has not been described. METHODS AND RESULTS: We used digital calipers and quantitative angiography to measure 517 arterial diameters (88 nonstenotic segments) in 24 transplant patients undergoing vasomotor function studies with acetylcholine and nitroglycerin, 20 stenoses in 14 patients with coronary artery disease, and 15 stenoses in 15 patients before and after excimer laser-facilitated coronary angioplasty and at 6 months' follow-up. In nonstenotic arterial segments ranging in size from 0.6 to 3.5 mm, calipers overestimated diameters measured by quantitative angiography by 0.29 +/- 0.21 mm (mean +/- SD) (limits of agreement, -0.13 to 0.71 mm). However, when the vasomotor responses were expressed as percent diameter change, the two methods did not differ significantly (-1 +/- 10%; limits of agreement, -21% to 19%). In the 35 stenoses measured before intervention and 30 stenoses measured after intervention, calipers and quantitative angiography differed by 3 +/- 9% (limits of agreement, -15% to 21%) across a range of stenosis severity (11% to 80%). Repeat caliper measurements by the same observer of the percent diameter change in the transplant patients and the percent stenosis in the coronary artery disease patients led to standard deviations of the differences of 9.3% and 7.6%, respectively. Two different observers recorded percent diameter change and percent stenosis that differed with standard deviations of 9.6% and 7.8%, respectively. CONCLUSIONS: Quantitative angiography and electronic digital calipers produce similar relative changes in arterial diameters and percent stenosis in a broad range of severities. Digital calipers thus are a rapid and convenient alternative to computerized quantitative angiography in certain research studies and clinical practice of assessing stenosis severity.

Coronary Angiography↗
PubMed1999

The effectiveness of videophones in home healthcare for the elderly.

OBJECTIVES: This study evaluates the effectiveness of telecare, the use of videophones in healthcare for the elderly in communities, and proposes an effective application of telecare in home healthcare. METHODS: An intervention study design was applied to evaluate the add-on benefits to home healthcare from a videophone system using Integrated Services Digital Network (ISDN) installed in individual homes of clients and service providers. An intervention group of home healthcare cases were provided with videophones (VHHC group), and it was compared to a reference group of regular healthcare cases (HHC group). Persons from the 2 groups were individually matched according to sex, age, and their independence in activities of daily living. The functional independence of the individuals in the 2 groups was assessed before and 3 months after home healthcare was started, with and without videophones. The effectiveness of videophones was assessed by analyzing the improvements in functional independence using a paired t test. RESULTS: Improvements in functional independence of 5 pairs of males and 11 pairs of females were analyzed. Improvements in ADL, communication, and social cognition independence of the VHHC group over the 3-month trial period measured by the Functional Independence Measure were 1.5 points, 0.7 points, and 1.9 points, respectively; statistically, these were significantly greater than those of the HHC group (individually P < 0.05). CONCLUSIONS: The effectiveness of the videophones in home healthcare service was found to be significant. This evidence supports the use of videophones in home healthcare to improve the quality of service.

Activities of Daily Living↗
PubMed2006

Improving the quality of preventive cardiovascular care provided by primary care physicians: insights from a US Quality Improvement Organization.

BACKGROUND: During 2000-03, Qualidigm, a US Quality Improvement Organization, conducted a project to improve the care received by elderly Medicare patients with coronary artery disease or cardiovascular risk factors. METHODS: We recruited primary care physicians in private practice in the state of Connecticut. Then, we identified approximately 30-50 patients per physician from the periods 1 January 2000 to 31 December 2000 and 1 November 2001 to 31 October 2002. We abstracted medical records to assess processes and outcomes of care, and we provided the physicians with performance data and a variety of practice-enhancing materials. The physicians utilized those materials that they perceived to be most helpful. RESULTS: We identified and recruited 974 primary care physicians to participate. Of these, 103 (10.6%) committed to participate, and 85 of the 103 completed the project. Among the intervention tools, physicians and their office personnel utilized personal digital assistants (PDAs) (36.5%) and patient education materials (34.1%) most commonly. Overall, quality of care improved for most physicians (mean quality score 62.0 to 67.8%, P < 0.001). However, not all improved, and most improvements were modest [mean absolute improvement in quality score 5.8%, standard deviation (SD) 6.8%]. CONCLUSIONS: Quality Improvement Organizations and others interested in improving outpatient quality of care face significant challenges in recruiting self-employed primary care physicians to quality improvement projects and in bringing about transformational change. Future primary care quality improvement projects should include careful assessments of practice-specific barriers, interventions that are linked to these barriers, and support of the practices on implementation.

Aged↗
PubMed2026

Effects of Digital Mental Health Screening Alone and With the Online MINDBODYSTRONG CBT-Based Program on Burnout, Depression, Anxiety, Healthy Behaviors, and Suicidal Ideation in at-Risk Nurses at 3- and 6-Months Post-Intervention: An&#xa0;RCT.

BACKGROUND: Burnout and mental distress among nurses are global public health epidemics that adversely affect nurse well-being and healthcare quality. Evidence-based, scalable mental health interventions are urgently needed. AIMS: To evaluate the 3- and 6-month outcomes of a randomized controlled trial (RCT) comparing a psychologically safe, digital mental health screening and referral program alone versus the same screening and referral program combined with the video-based online MINDBODYSTRONG&#xa0;(MBS) cognitive behavioral therapy (CBT)-based skills-building program among nurses at risk for mental distress. METHODS: 501 nurses were recruited from professional organizations and healthcare systems across the United States by email and randomized to either mental health screening and referral (standard care) or standard care plus the MBS cognitive behavioral skills-building intervention (the intervention). All study activities were conducted remotely. Follow-up surveys administered at 3- and 6-months assessed anxiety, depression, suicidal ideation, burnout, healthy lifestyle beliefs, and healthy lifestyle behaviors using valid and reliable scales. RESULTS: Compared with the screening and referral only group, participants in the intervention group had greater reductions in anxiety and depression and significantly greater increases in healthy lifestyle beliefs and behaviors at 3 and 6&#x2009;months post-intervention. After controlling baseline risk, the intervention group had a lower risk of suicidal ideation than the screening and referral group at 3&#x2009;months (relative risk ratio [RRR]&#x2009;=&#x2009;0.717; 95% CI: 0.320-1.606) and 6&#x2009;months (RRR&#x2009;=&#x2009;0.329; 95% CI: 0.101-1.072). The intervention group also had a significantly lower risk of burnout at 6&#x2009;months (RRR: 0.698, 95% CI: 0.528, 0.929, p&#x2009;=&#x2009;0.012). Nurses who completed more MBS sessions had less suicidal ideation at 6&#x2009;months and those who completed more MBS skills-building activities had less burnout at 3 and 6&#x2009;months. LINKING ACTION TO EVIDENCE: Integrating psychologically safe mental health screening combined with the scalable online CBT-based intervention, MBS, can produce sustained improvements in burnout, mental health symptoms, including suicidality, and healthy lifestyle beliefs and behaviors among nurses experiencing mental distress.

Humans↗
PubMed1998

[The significance of magnetic resonance venography in the pre-interventional clarification of a malignant superior venous obstruction].

PURPOSE: Comparison between peripheral digital subtraction venography (DSV) and magnetic resonance venography (MRV) in planning for stent placement in malignant superior central venous obstruction. METHOD: 19 patients with malignant central vein obstruction were examined by DSV (n = 19) and MRV (n = 19). For each patient 12 segment-vessel evaluation was performed to review for obstruction and then compared with the gold standard--selective catheter phlebography--performed at the time of stent insertion. Additionally, tumor extension and collateral venous outflow was noted. RESULTS: Sensitivity, specificity, and accuracy amounted to 92%, 96%, and 95% for DSV and 98%, 100%, and 100%, respectively for MRV. The McNemar test revealed a significance between MR venography and DSV. CONCLUSIONS: With regard to planning of stent placement, a more exact evaluation was possible with MR venography than with DSV. Thus, MR venography can replace DSV as the method of choice for clarifying malignant superior central vein obstructions prior to stent placement.

Adult↗
PubMed2001

[Acute peripheral arterial ischemia: diagnosis and interventional therapy].

Acute peripheral arterial ischaemia is characterized by a rapidly developing perfusion deficiency with potential necrosis of the involved extremity. In more than 90% an embolic or thromboembolic etiology is present. Differential diagnosis includes all other vascular disease entities. Digital subtraction angiography is the radiological modality of choice for diagnosis and interventional therapy. Prior to a planned local fibrinolytic therapy potential contraindications have to be excluded.

Acute Disease↗
PubMed1993

Various intensities of leisure time physical activity in patients with coronary artery disease: effects on cardiorespiratory fitness and progression of coronary atherosclerotic lesions.

OBJECTIVES: This study was designed to define the effect of different levels of leisure time physical activity on cardiorespiratory fitness and progression of coronary atherosclerotic lesions in unselected patients with coronary artery disease. BACKGROUND: It has been shown in various studies that regression of coronary atherosclerotic lesions can be achieved by means of lipid-lowering drugs, reduction of fat consumption and physical exercise. METHODS: Patients were prospectively randomized either to an intervention group (n = 29) participating in regular physical exercise or to a control group (n = 33) receiving usual care. Energy expenditure in leisure time physical activity was estimated from standardized questionnaires and from participation in group exercise sessions. After 12 months of participation, repeat coronary angiography was performed; coronary lesions were measured by digital image processing. RESULTS: After 1 year, patients in the intervention group achieved an increase in oxygen uptake at a ventilatory threshold of 7% (p < 0.001) and peak exercise of 14% (p < 0.05), whereas a significant decrease was observed in patients in the control group. To achieve significant improvement in cardiorespiratory fitness, approximately 1,400 kcal/week had to be expended in the form of leisure time physical activity (p < 0.001). The mean energy expended in such activity was 1,876 +/- 163 kcal/week in the intervention group and 1,187 +/- 97 kcal/week in the control group (p < 0.001). In the intervention group, regression of coronary artery disease was noted in 8 patients (28%), progression of disease in 3 (10%) and no change in coronary morphology in 18 (62%). In contrast, coronary artery disease progressed at a significantly faster rate in patients in the control group (progression in 45%, no change in 49% and regression in 6%) (p < 0.001 vs. intervention). When the two groups were combined, the lowest level of leisure time physical activity was noted in patients with progression of disease (1,022 +/- 142 kcal/week) as opposed to patients with no change (1,533 +/- 122 kcal/week) or regression of disease (2,204 +/- 237 kcal/week) (p < 0.005). CONCLUSIONS: Measurable improvement in cardiorespiratory fitness requires approximately 1,400 kcal/week of leisure time physical activity; higher work loads are necessary to halt progression of coronary atherosclerotic lesions (1,533 +/- 122 kcal/week), whereas regression of coronary lesions is observed only in patients expending an average of 2,200 kcal/week in leisure time physical activity, amounting to approximately 5 to 6 h/week of regular physical exercise.

Coronary Angiography↗
PubMedDate not supplied

Canine digital tumors: a veterinary cooperative oncology group retrospective study of 64 dogs.

We compared clinical characteristics and outcomes for dogs with various digital tumors. Medical records and histology specimens of affected dogs from 9 veterinary institutions were reviewed. Risk factors examined included age, weight, sex, tumor site (hindlimb or forelimb), local tumor (T) stage, metastases, tumor type, and treatment modality. The Kaplan-Meier product limit method was used to determine the effect of postulated risk factors on local disease-free interval (LDFI), metastasis-free interval (MFI), and survival time (ST). Outcomes were thought to differ significantly between groups when P < or = .003. Sixty-four dogs were included. Squamous cell carcinoma (SCC) accounted for 33 (51.6%) of the tumors. Three dogs presented with or developed multiple digital SCC. Other diagnoses included malignant melanoma (MM) (n = 10; 15.6%), osteosarcoma (OSA) (n = 4; 6.3%), hemangiopericytoma (n = 3; 4.7%), benign soft tissue tumors (n = 5; 7.8%), and malignant soft tissue tumors (n = 9; 14%). Fourteen dogs with malignancies had black hair coats, including 5 of the 10 dogs with MM. Surgery was the most common treatment and, regardless of the procedure, had a positive impact on survival. None of the patient variables assessed, including age, sex, tumor type, site, and stage, had a significant impact on ST. Both LDFI and MFI were negatively affected by higher T stage, but not by type of malignancy. Although metastasis at diagnosis correlated with a shorter LDFI, it did not have a significant impact on ST. On the basis of these findings, early surgical intervention is advised for the treatment of dogs with digital tumors, regardless of tumor type or the presence of metastatic disease.

Age Factors↗
PubMed2005

Accuracy of screening for fecal occult blood on a single stool sample obtained by digital rectal examination: a comparison with recommended sampling practice.

BACKGROUND: Many expert panels recommend colorectal cancer screening for average-risk asymptomatic individuals older than 50 years of age. Recent studies have found that 24% to 64% of primary care providers use only the digital fecal occult blood test (FOBT) as their primary screening test. The effectiveness of a single digital FOBT is unknown. OBJECTIVE: To compare the sensitivity and specificity of digital FOBT and the recommended 6-sample at-home FOBT for advanced neoplasia in asymptomatic persons. DESIGN: Prospective cohort study. SETTING: 13 Veterans Affairs medical centers. PATIENTS: 3121 asymptomatic patients 50 to 75 years of age. INTERVENTION: 2665 patients had 6-sample at-home FOBT and digital FOBT, followed by complete colonoscopy. MEASUREMENTS: We measured the sensitivity of digital and 6-sample FOBT for advanced neoplasia and the specificity for no neoplasia. We calculated predictive values and likelihood ratios for advanced neoplasia, defined as tubular adenomas 10 mm or greater, adenomas with villous histology or high-grade dysplasia, or invasive cancer. RESULTS: Of all participants, 96.8% were men; their average age was 63.1 years. The 6-sample FOBT and the single digital FOBT had specificities of 93.9% and 97.5%, respectively, as defined by studying 1656 patients with no neoplasia. Sensitivities for detection of advanced neoplasia in 284 patients were 23.9% for the 6-sample FOBT and 4.9% for the digital FOBT. The likelihood ratio for advanced neoplasia was 1.68 (95% CI, 0.96 to 2.94) for positive results on digital FOBT and 0.98 (CI, 0.95 to 1.01) for negative results. LIMITATIONS: Most patients were men. CONCLUSIONS: Single digital FOBT is a poor screening method for colorectal neoplasia and cannot be recommended as the only test. When digital FOBT is performed as part of a primary care physical examination, negative results do not decrease the odds of advanced neoplasia. Persons with these results should be offered at-home 6-sample FOBT or another type of screening test.

Aged↗
PubMed2007

B-flow and B-flow with 3D and SRI postprocessing before intervention and monitoring after stenting of the internal carotid artery.

OBJECTIVE: To investigate the extent to which B-flow and B-flow with 3D postprocessing and speckle reduction imaging (SRI) have advantages in appraising the morphology of a high-grade stenosis of the internal carotid artery (ICA) for preinterventional planning and for postinterventional ultrasonographic follow-up. MATERIALS/METHODS: A comparative appraisal of flow with CCDS, power Doppler, B-flow and 3D B-Flow with SRI were carried out prospectively in 50 patients with >70% stenosis according to NASCET criteria in contrast medium-enhanced MRA before and after the intervention. After stenting of the internal carotid artery (ICA), i.a. digital substraction angiography (DSA) served as an additional reference method. RESULTS: In >70% ICA stenosis, simultaneous imaging of the pre-stenotic, intra-stenotic and post-stenotic flow was attained with B-flow in 45/90 cases (90%), with power Doppler in 39/50 cases (78%) and with CCDS in only 31/50 cases (62%). After intervention, a complete detection of flow without overwriting or blooming artifacts was achieved in all 50 patients only by B-flow. The intrastenotic flow (p<0.05) could be better demarcated against the lumen and the vessel wall before the intervention, whereas the flow within the stent could be very much better appraised after the intervention (p<0.01) using 3D postprocessing of B-flow with additional SRI. Re-stenoses with hypoechoic vascular wall changes (3/50 patients) were detected at an early stage using B-flow. CONCLUSIONS: B-flow technique with SRI and 3D postprocessing can facilitate the intrastenotic detection of flow in >70% ICA stenosis with fewer flow artifacts. After stenting, the perfused vascular lumen shows less flow artifacts compared with CCDS and power Doppler. In order to elucidate hemodynamic changes, additional Doppler examinations are still necessary.

Aged↗
PubMed2002

Gadolinium chelates in angiography and interventional radiology: a useful alternative to iodinated contrast media for angiography.

Gadolinium has physical properties that are well suited for radiographic imaging. Digital subtraction angiography with a gadolinium chelate as contrast medium can provide images of suitable quality for diagnosis and intervention. The overall safety profile of gadolinium-based contrast media is excellent. In particular, these contrast media are well tolerated in patients with renal insufficiency when administered intraarterially in doses of less than 0.3-0.4 mmol per kilogram body weight, with a decreased incidence of contrast medium-induced nephropathy, as compared with similar volumes of iodinated contrast material. The currently available formulations of gadolinium chelates can be injected safely into every arterial and venous structure. However, substantial data are lacking on the intraarterial use of gadolinium in patients with renal insufficiency, particularly at doses that exceed those routinely used in magnetic resonance angiography. Gadolinium chelates in appropriate volumes are useful alternative contrast media in selected high-risk patients undergoing angiographic studies.

Angiography↗
PubMed2006

Digital imaging in the fabrication of ocular prostheses.

Several ocular and orbital disorders require surgical intervention that may result in ocular defects. The associated psychological effect of these defects on the patient requires immediate management and rehabilitation intervention by a team of specialists. The role of the maxillofacial prosthodontist in fabricating an ocular prosthesis with acceptable esthetics to restore facial symmetry and normal appearance for the anophthalmic patient becomes essential. This article presents a technique for fabricating ocular prostheses using the advantages of digital photography.

Eye, Artificial↗
PubMed2002

Evaluation of a miniature electromagnetic position tracker.

The advent of miniaturized electromagnetic digitizers opens a variety of potential clinical applications for computer aided interventions using flexible instruments; endoscopes or catheters can easily be tracked within the body. With respect to the new applications, the systematic distortions induced by various materials such as closed metallic loops, wire guides, catheters, and ultrasound scan heads were systematically evaluated in this paper for a new commercial tracking system. We employed the electromagnetic tracking system Aurora (Mednetix/CH, NDI/Can); data were acquired using the serial port of a PC running SuSE Linux 7.1 (SuSE, Gmbh, Nürnberg). Objects introduced into the digitizer volume included wire loops of different diameters, wire guides, optical tracking tools, an ultrasonic (US) scan head, an endoscope with radial ultrasound scan head and various other objects used in operating rooms and interventional suites. Beyond this, we determined the influence of a C-arm fluoroscopy unit. To quantify the reliability of the system, the miniaturized sensor was mounted on a nonmetallic measurement rack while the transmitter was fixed at three different distances within the digitizer range. The tracker was shown to be more sensitive to distortions caused by materials close to the emitter (average distortion error 13.6 mm +/- 16.6 mm for wire loops positioned at a distance between 100 mm and 200 mm from the emitter). Distortions caused by materials near the sensor (distances smaller than 100 mm) are small (typical error 2.2 mm +/- 1.9 mm). The C-arm fluoroscopy unit caused considerable distortions and limits the reliability of the tracker (distortion error 18.6 mm +/- 24.9 mm). Distortions resulting from the US scan head are high at distances smaller than about 100 mm from the emitter. The distortions also increase when the scan head is positioned horizontally and close to the sensor (average error 4.1 mm +/- 1.5 mm when the scan head is positioned within a distance of 100 mm from the sensor). The distortions are slightly higher when the ultrasound machine is switched on. We also evaluated the influence of common medical instruments on distance measurements. For these measurements the average deviation from the known distance of 200 mm amounted to 3.0 mm +/- 1.5 mm (undistorted distance measurement 1.5 mm +/- 0.3 mm). The deviations also depend on the relative orientation between emitter and sensor. The results demonstrate that the miniature tracking system opens up new perspectives with regard to surgery applications where a flexible instrument is to be tracked within the body. Significant distortions caused by metallic objects only occur in the worst cases, for example, in the presence of a closed, unisiolated wire loop or a C-arm fluorescence unit close to the emitter and which can be avoided by suitable usage.

Calibration↗