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PubMed1998

The effects of halothane on abnormal automaticity in canine cardiac Purkinje fibers.

UNLABELLED: Abnormal automaticity is the spontaneous beating of cardiac cells with abnormally depolarized resting membrane potentials. The effects of halothane on cardiac arrhythmias caused by abnormal automaticity are controversial, with either antiarrhythmic effects or enhancement of abnormal automaticity reported by different authors. The goal of the present investigation was to clarify the effects of halothane on abnormal automaticity induced by superfusing excised canine Purkinje fibers (PF) with barium chloride. Intracellular microelectrodes recorded action potentials from fibers superfused with buffer solution in a tissue bath. Barium chloride 0.25 mM reduced maximal diastolic potential from -82.1 +/- 5.6 mV to -67.4 +/- 9.4 mV (mean +/- SD, P < 0.05). Fibers developed abnormal automatic rhythms at a rate of 47.1 +/- 5.9 bpm. Halothane, 0.5%-4%, was added to the superfusate. Halothane reduced the rate of firing in a dose-dependent manner, so that abnormal automaticity was abolished by 4% halothane and reduced by lesser concentrations. Serendipitously, during barium superfusion, two additional fibers developed early afterdepolarizations, a cause of triggered arrhythmias in patients with long Q-T syndrome. Halothane abolished early afterdepolarizations in each. In this model of barium toxicity in excised canine PF, halothane antagonized both abnormal automaticity and early afterdepolarizations. IMPLICATIONS: Life-threatening cardiac arrhythmias may occur during anesthesia. An arrhythmia called abnormal automaticity occurs after heart attacks and can be mimicked by adding barium to small segments of heart tissue. Halothane abolished abnormal automaticity in these tissues, which suggests that it or similar agents may benefit patients prone to developing such abnormal rhythms during surgery.

Action Potentials↗
PubMed2006

QT interval measurement: evaluation of automatic QTc measurement and new simple method to calculate and interpret corrected QT interval.

BACKGROUND: Assessment of repolarization duration is often recommended to avoid administration of QT-prolonging drugs in patients with prolonged QTc interval, a frequent situation in the postoperative period. Bazett QT correction inappropriately increases QTc when heart rate is increased, and the use of the Fridericia formula may avoid a falsely prolonged QTc interval. The authors assessed automatic QT interval measurement to detect prolonged QTc interval (women >450 ms; men >440 ms) in the postoperative setting. METHODS: Automatic and manual electrocardiograms were performed in 108 patients after anesthesia. Automatic electrocardiographic measurement used the Bazett formula. Manual measurements were made from each electrocardiogram and used as the reference. Agreement between the two methods was analyzed. Bazett and Fridericia QT corrections were compared in this population. RESULTS: Agreement between automatic and manual measurements was low. The Fridericia correction, but not the Bazett correction, was independent from heart rate and allowed adequate QT correction. Sensitivity of automatic measurements to detect prolonged QTc-Bazett interval was 54%. Automatic QTc-Bazett interval less than 430 ms ruled out a manual prolonged QTc interval. When automatic QTc-Bazett was greater than 430 ms, this value was converted according to Fridericia. Automatic QTc-Fridericia greater than 430 ms identified all patients with prolonged manual QTc with a negative predictive error of 0% (95% confidence interval, 0-7%). QTc-Fridericia can be approximated by respectively adding or subtracting 5% to the uncorrected QT for each increase or decrease by 10 beats/min in heart rate from 60 beats/min. CONCLUSIONS: Automatic QTc-Bazett measurement, if abnormal, associated with calculation of QTc-Fridericia reliably identifies patients in whom manual QTc measurement must be performed to confirm postoperative prolonged QTc interval.

Adult↗
PubMedDate not supplied

Pregnant women: Moiré contourgraph and it's semiautomatic and automatic evaluation. Dedicated to Professor Antonín Dolezal on his 75th birthday anniversary.

THE AIM OF THE STUDY: Methods of automatic and semiautomatic picture determination, evaluation of Moiré contourgraph applied to pregnant women TYPE OF THE STUDY: Development of algorithm, experimental biomechanical study of the dynamics of pregnant women's axial system. METHOD: Achieving the correct data for 3D picture analysis derived from 2D pictures requires further precision making. In general, it requires algorithmization and elaboration of software plug-in, which make processing of enormous number of picture data significantly faster. The following corrections, adjustments and calculations had to be done to be used for Moiré contourgraph: correction of the radial distortion of the lens--automatically, aligning the histogram--automatically, picture detection of the defined object shape and determining its centre of gravity with sub-pixel precision--automatically, centre of gravity of the picture of the cross-section of pseudo-contour line of the Moiré contourgraph--semi-automatically, correction of radial shifts in 2D-data orthonormalization--semi-automatically, determining the distance of a projected point in 2D from the net as z-coordinate in 3D--semi-automatically, a) points projected in 2D picture on the pseudo-contour line, b) points not projected in 2D picture on the pseudo-contour line. RESULTS: Algorithmization of each approach leading to semi-automatic and automatic processing of data obtained from Moiré contourgraphs. Main distortions, errors and inaccuracy of picture data are eliminated. The resulting position of the detected point in 3D derived from the 2D picture is determined with sub-pixel precision of primary picture coordinates. CONCLUSION: Precision given to coordinates of reference points obtained from original picture data allows for eliminating limiting inaccuracy in determining real coordinates of a 3D object from 2D Moiré contourgraph. Coordinates of a virtual model of a real object corresponding to its real values are determined. This makes the base for non-invasive recording and reconstruction of data on the human body's shape including the details in 3D. The presented file of methods will be used to assess dynamics of the women's axial system during their pregnancy and one year after giving birth.

Algorithms↗
PubMed1992

Attention and preattention in theories of automaticity.

The theoretical relation between preattentive processes and automatic processes is different in different approaches to attention and automaticity. In the modal view, automatic and preattentive processes are one and the same; automatic processing is preattentive. In recent views that treat automaticity as a memory phenomenon, automatic processing is postattentive. These views are described and evidence for them is discussed. Two experiments are reported that test whether the training that makes processing automatic also makes it preattentive. The data suggest a dissociation between automatic and preattentive processes that is more consistent with the memory view of automaticity than with the modal view.

Adult↗
PubMed1998

Design and validation of a new image analysis method for automatic quantification of interstitial fibrosis and glomerular morphometry.

Interstitial fibrosis and morphologic changes in kidney glomeruli, the structural effects of many diseases, lead to significant pathologic alterations. A reliable and objective method to accurately quantify the extent of interstitial fibrosis and the degree of alteration in glomerular morphology is needed for both clinical practice and experimental work. The morphometric methods of quantification described to date are time-consuming and require trained personnel. This article describes the design and validation of an image analysis-based application (Fibrosis HR) for automatically and rapidly quantifying interstitial fibrosis and glomerular morphology in the same tissue section stained with Sirius red. The image processing algorithms described herein automatically segment interstitial fibrosis and mesangial matrix using automatic thresholding and morphologic filtering. The glomerular region is extracted by a simple interactive step and an automatic mathematical morphology algorithm, whereas the glomerular tuft is automatically segmented with automatic thresholding and a sequence of Boolean and mathematical morphology operations. All extracted areas are automatically quantified in absolute (microm2) and relative (%) values. For validation of this method, interstitial fibrosis, mesangial matrix, and glomerular and glomerular tuft areas were manually segmented and their quantifications statistically compared with those obtained automatically. Statistical analyses showed significant intra- and interoperator variability in manual segmentation of interstitial fibrosis, mesangial matrix, and glomerular tuft areas. Automatic quantifications of the same areas did not differ significantly from their mean manual evaluations. There was no significant intra- or interoperator variability in the interactive identification of the glomerular region. In conclusion, Fibrosis HR produces robust, fully reproducible, accurate, objective, and reliable quantifications, which facilitate the evaluation of in vivo experimental models of renal interstitial and glomerular pathologies and improve the accuracy of clinicopathologic analyses of renal diseases in human biopsies.

Algorithms↗
PubMed2002

Comparing techniques for estimating automatic retrieval: effects of retention interval.

Results from implicit memory (IM) tasks suggest that automatic retrieval remains stable or decreases over time. In contrast, results from the process dissociation approach (PDA) suggest that automatic retrieval may actually increase over time. One explanation for these discrepant results is that performance on IM tasks is contaminated by controlled retrieval strategies, thereby overestimating automatic retrieval, particularly at short retention intervals, when controlled retrieval strategies are high. An alternative explanation is that automatic and controlled retrieval are positively correlated, rather than independent as assumed by the PDA. If so, the PDA would underestimate automatic retrieval, particularly when controlled retrieval strategies are high. Results from a speeded IM task suggest that a standard IM task provided an accurate estimate of automatic retrieval, whereas the PDA underestimated automatic retrieval at a short retention interval. This pattern of underestimation by the PDA supports the conclusion that automatic and controlled retrieval were positively correlated rather than independent.

Automatism↗
PubMed2006

Facilitating coronary artery evaluation in MDCT using a 3D automatic vessel segmentation tool.

The purpose of this study was to investigate a 3D coronary artery segmentation algorithm using 16-row MDCT data sets. Fifty patients underwent cardiac CT (Sensation 16, Siemens) and coronary angiography. Automatic and manual detection of coronary artery stenosis was performed. A 3D coronary artery segmentation algorithm (Fraunhofer Institute for Computer Graphics, Darmstadt) was used for automatic evaluation. All significant stenoses (>50%) in vessels >1.5 mm in diameter were protocoled. Each detection tool was used by one reader who was blinded to the results of the other detection method and the results of coronary angiography. Sensitivity and specificity were determined for automatic and manual detection as well as was the time for both CT-based evaluation methods. The overall sensitivity and specificity of the automatic and manual approach were 93.1 vs. 95.83% and 86.1 vs. 81.9%. The time required for automatic evaluation was significantly shorter than with the manual approach, i.e., 246.04+/-43.17 s for the automatic approach and 526.88+/-45.71 s for the manual approach (P<0.0001). In 94% of the coronary artery branches, automatic detection required less time than the manual approach. Automatic coronary vessel evaluation is feasible. It reduces the time required for cardiac CT evaluation with similar sensitivity and specificity as well as facilitates the evaluation of MDCT coronary angiography in a standardized fashion.

Aged↗
PubMed1989

Observed use of automatic seat belts in 1987 cars.

Usage of the automatic belt systems supplied by six large-volume automobile manufacturers to meet the federal requirements for automatic restraints were observed in suburban Washington, D.C., Chicago, Los Angeles, and Philadelphia. The different belt systems studied were: Ford and Toyota (motorized, nondetachable automatic shoulder belt), Nissan (motorized, detachable shoulder belt), VW and Chrysler (nonmotorized, detachable shoulder belt), and GM (nonmotorized detachable lap and shoulder belt). Use of automatic belts was significantly greater than manual belt use in otherwise comparable late-model cars for all manufacturers except Chrysler; in Chrysler cars, automatic belt use was significantly lower than manual belt use. The automatic shoulder belts provided by Ford, Nissan, Toyota, and VW increased use rates to about 90%. Because use rates were lower in Ford cars with manual belts, their increase was greater. GM cars had the smallest increase in use rates; however, lap belt use was highest in GM cars. The other manufacturers supply knee bolsters to supplement shoulder belt protection; all--except VW--also provide manual lap belts, which were used by about half of those who used the automatic shoulder belt. The results indicate that some manufacturers have been more successful than others in providing automatic belt systems that result in high use that, in turn, will mean fewer deaths and injuries in those cars.

Accident Prevention↗
PubMed1984

Symposium on the management of ventricular dysrhythmias. Concept of reentry versus automaticity.

Arrhythmias can result from abnormal impulse initiation or conduction. Abnormal initiation results from either automaticity or triggered activity. Enhanced automaticity may be due to a normal automatic mechanism (a normal property of the sinus node and specialized conducting fibers) or to an abnormal mechanism such as automaticity in depolarized fibers. Triggered activity is caused by afterdepolarizations that occur either during repolarization (early afterdepolarization) or after repolarization is complete (delayed afterdepolarization). Triggered activity due to delayed afterdepolarizations is dependent on critical heart rates. Overdrive pacing may distinguish between normal and abnormal automaticity. Antiarrhythmic drugs can alter arrhythmias that result from abnormal impulse initiation. To suppress an arrhythmia resulting from abnormal impulse generation, a drug may (1) suppress the abnormal automatic mechanism, i.e., specific effect on ionic current; (2) suppress afterdepolarizations; (3) depress conduction in tissue surrounding automatic focus; or (4) modify refractory period of tissue in and around automatic focus. Abnormal impulse conduction results in reentrant excitation. Conditions necessary for reentry include a combination of unidirectional block and slowed conduction. A reentrant mechanism can be determined by an anatomically defined circuit or solely by the functional properties of the tissue (leading circle mechanism). Circus movement reentry around an anatomic obstacle may respond to antiarrhythmic drugs differently from reentry caused by a leading circle mechanism. Initiation and perpetuation of a reentry mechanism depends on a delicate interplay between conduction velocity and duration of the functional refractory period in the reentry circuit.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1988

Comparison of automatic and voluntary chewing patterns and performance.

Chewing, like respiration, is ordinarily performed as an automatic motor act, yet both can be voluntarily controlled. No in-depth analyses of voluntary chewing exist. Therefore, we have analyzed on a cycle-by-cycle basis voluntarily controlled chewing, and compared it with automatic chewing. We assessed the performance during voluntarily controlled chewing by obtaining constant error and variable error scores. Nine healthy adults with full dentition were subjects (Ss). Their three-dimensional jaw movements and movement times were derived from Kinesiograph recordings obtained while chewing a standard piece of gum on the right side of the mouth. Burst durations and onset latencies of masseter activity were obtained from surface-recorded EMGs. Frequency during automatic chewing was obtained from data recorded while the subject viewed a film. Next, the subject chewed in time with a metronome set at this "automatic" rate. Intrasubject variability among 30 consecutive chewing cycles during voluntary was less than during automatic chewing. In every S gape and ipsilateral jaw excursions and the variability of burst durations of masseter activity were less during voluntary than during automatic chewing, showing that both the spatial and temporal aspects of the two types of chewing differ significantly. Ss varied in ability to follow the metronome. A S's constant error might be small, yet his variable error might be large, as if feed-back-based corrections influenced cycle-to-cycle variability. Fast chewers had smaller constant and variable error scores than did slow chewers, suggesting a speed-accuracy relationship. In summary, both temporal and spatial aspects of voluntary chewing were modified compared with those of automatic chewing. During voluntarily controlled chewing, cycle-to-cycle variability was less compared with automatic chewing due to reductions in variability of occlusal phase and the masseter's burst durations, and total jaw excursions were less because gapes and ipsilateral deviations during closing were reduced.

Adult↗
PubMed2006

The transition to increased automaticity during finger sequence learning in adult males who stutter.

UNLABELLED: The present study compared the automaticity levels of persons who stutter (PWS) and persons who do not stutter (PNS) on a practiced finger sequencing task under dual task conditions. Automaticity was defined as the amount of attention required for task performance. Twelve PWS and 12 control subjects practiced finger tapping sequences under single and then dual task conditions. Control subjects performed the sequencing task significantly faster and less variably under single versus dual task conditions while PWS' performance was consistently slow and variable (comparable to the dual task performance of control subjects) under both conditions. Control subjects were significantly more accurate on a colour recognition distracter task than PWS under dual task conditions. These results suggested that control subjects transitioned to quick, accurate and increasingly automatic performance on the sequencing task after practice, while PWS did not. Because most stuttering treatment programs for adults include practice and automatization of new motor speech skills, findings of this finger sequencing study and future studies of speech sequence learning may have important implications for how to maximize stuttering treatment effectiveness. EDUCATIONAL OBJECTIVES: As a result of this activity, the participant will be able to: (1) Define automaticity and explain the importance of dual task paradigms to investigate automaticity; (2) Relate the proposed relationship between motor learning and automaticity as stated by the authors; (3) Summarize the reviewed literature concerning the performance of PWS on dual tasks; and (4) Explain why the ability to transition to automaticity during motor learning may have important clinical implications for stuttering treatment effectiveness.

Adult↗
PubMed2003

Comparison of automatic repolarization measurement techniques in the normal magnetocardiogram.

Multichannel MCG noninvasively measures cardiac magnetic field strength from many sites at the body surface, potentially providing useful regional information about ventricular repolarization. Previous work on ECGs has shown that automatic techniques for repolarization measurement are better than manual measurement at discriminating patients with cardiac conditions from normal subjects. Although automatic repolarization measurement techniques have been quantified for ECGs, no comparative data exists for the MCG. In this study four different automatic repolarization (QT) interval techniques for detecting T wave end in the MCG were compared. The influence of MCG filtering on the automatic algorithms was also quantified. MCGs were obtained at 49 sites over the heart from 23 normal subjects. Automatic measurements of the repolarization (QT) interval were made following the addition of different high pass (0.25, 0.5, 1 Hz) and low pass (100, 60, 40, 30 Hz) filters. There were consistent differences between automatic techniques in the unfiltered data amounting to greatest mean difference of 52.3 ms. Low pass filtering significantly increased the automatic repolarization (QT) interval relative to unfiltered measurement by 6.5 (3.2) ms (mean SD) for 100 Hz, 6.0 (3.0) ms for 60 Hz, 8.1 (3.2) ms for 40 Hz, and 8.8 (3.1) ms for 30 Hz across all techniques. High pass filtering significantly decreased the value by -2.6 (6.0) ms for 0.25 Hz, -5.5 (5.3) ms for 0.5 Hz, and -17.1 (7.8) ms for 1 Hz. Automatic measurements of repolarization (QT) in the MCG differ between techniques and are influenced by filtering. These effects should be considered when comparing results.

Analysis of Variance↗
PubMed2003

The importance of processing automaticity and temporary storage capacity to the differences in comprehension between skilled and less skilled college-age deaf readers.

The prevalence of low comprehension among deaf readers has been documented for decades, yet the problem persists. Progress has been hampered by uncertainty regarding which aspects of reading competence ought to be the primary focus of concerted instructional efforts. This article examines whether temporary storage capacity and/or processing automaticity may explain the difference in comprehension between skilled and less skilled adult deaf readers. Temporary storage capacity is the ability to maintain separate bits of information in current memory while they are being processed. Processing automaticity is the ability to complete certain basic operations of reading, such as recognizing individual words and chunking sets of words into meaningful phrases, with a minimum of intentional mental effort. In this study one group of deaf adults reading at the college level and another reading at the 5th-grade level completed a battery of experimental tasks that generated multiple indicators of storage capacity and automaticity. These included the reading span task of Daneman and Carpenter (1980), an analogous addition span task, two measures of phonological processing, and a sentence-reading task that varied the demands on temporary storage and processing automaticity. Results suggest that skilled readers do not command an exceptionally large temporary storage capacity, nor do less skilled readers suffer from deficient storage capacity. The indicators of processing automaticity suggest, however, that less skilled readers must invest significantly more conscious mental effort than skilled readers to complete basic operations of reading. These findings are applied to theory related to (a) the nature of the breakdowns in comprehension faced by readers with low automaticity, (b) the interaction of low automaticity with other obstacles to comprehension, and (c) the design of practice experiences to increase the automaticity and ultimately the comprehension of deaf readers.

Journal Article↗
PubMed2004

An automatic method for scoring leg movements in polygraphic sleep recordings and its validity in comparison to visual scoring.

STUDY OBJECTIVES: The study presents an automatic method for scoring leg movements in polysomnographic recordings and describes an empirical investigation of its validity. DESIGN: Leg movements measured by means of the surface electromyogram activation of the right and left tibialis anterior muscle contained in 24 digitally recorded all-night polysomnograms were analyzed visually according to the American Sleep Disorders Association guidelines by 2 experienced raters and automatically scored using a newly developed electromyogram-based analytical method. Two visual scorings and the automatic scoring were compared in pairs using descriptive and confirmative statistical methods. SETTING: N/A. PARTICIPANTS: All-night polysomnograms of adaptation nights at the sleep laboratory of 10 patients with idiopathic restless legs syndrome (RLS) according to the International RLS Study Group. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Agreement rates between the 2 well-trained scorers and the automatic method were comparable. Based on the first scorer's results (100%) 92.5% of the movements were detected by the second scorer and 94.3% by the automatic method. When the visual scorings were compared, the rate of false-positive and false-negative errors were 7% and 3%, respectively. Comparing both visual scorings with the results of the automatic scoring yielded false-positive and false-negative rates in the range from 3% to 8%. CONCLUSIONS: The degree of accordance between the 2 visual scorings and between the visual and the automatic scorings were comparable. Therefore, this method is valid and may be used for the automatic detection of leg movements in future studies.

Electromyography↗
PubMed1987

Does if control normal automatic rate in canine cardiac Purkinje fibers? Studies on the negative chronotropic effects of lidoflazine.

Lidoflazine has been reported to decrease the conductance of the slow inward current and of the pacemaker current (if) in cardiac tissues. We studied the effects of lidoflazine on normal and abnormal automaticity in isolated preparations of canine and ovine cardiac Purkinje fibers. Normal automaticity occurred in fibers with maximum diastolic potentials (MDPs) greater than -85 mV, and abnormal automaticity occurred in fibers with MDPs less than -60 mV. Normal automaticity was studied in fibers superfused with Tyrode's solution containing 2.7 mM KCl, 4 mM KCl, 4 mM KCl with 1 microM isoproterenol (ISO), and 4 mM KCl with 25 microM BaCl2. In each experiment, normal automatic rate was stable for at least 30 min before lidoflazine was added to the superfusate; lidoflazine did not decrease the rates significantly in any of the four series of experiments. However, when fibers with normal MDPs were pretreated with lidoflazine, the drug blunted the increase in rate that occurred 12-15 min after the start of exposure to ISO. However, lidoflazine significantly decreased abnormal automaticity induced by barium (250 microM or 5 mM). The results indicate that normal automaticity in Purkinje fibers is not affected by lidoflazine and is probably not controlled by if. Rather, normal rate is controlled by the magnitude of background potassium conductance (gK), as indicated by the significant effects of barium (25 microM) on rate. Lidoflazine may blunt the effects of ISO on rate by inhibiting if, but after ISO rhythms are established, they are probably maintained by triggered impulses that are not affected by lidoflazine. Lidoflazine may slow abnormal automaticity by inhibition of the slow inward current.

Action Potentials↗
PubMed2006

Automatic measurement of vertebral rotation in idiopathic scoliosis.

STUDY DESIGN: Development of an automatic measurement algorithm and comparison with manual measurement methods. OBJECTIVES: To develop a new computer-based method for automatic measurement of vertebral rotation in idiopathic scoliosis from computed tomography images and to compare the automatic method with two manual measurement techniques. SUMMARY OF BACKGROUND DATA: Techniques have been developed for vertebral rotation measurement in idiopathic scoliosis using plain radiographs, computed tomography, or magnetic resonance images. All of these techniques require manual selection of landmark points and are therefore subject to interobserver and intraobserver error. METHODS: We developed a new method for automatic measurement of vertebral rotation in idiopathic scoliosis using a symmetry ratio algorithm. The automatic method provided values comparable with Aaro and Ho's manual measurement methods for a set of 19 transverse computed tomography slices through apical vertebrae, and with Aaro's method for a set of 204 reformatted computed tomography images through vertebral endplates. RESULTS: Confidence intervals (95%) for intraobserver and interobserver variability using manual methods were in the range 5.5 degrees to 7.2 degrees . The mean (+/-SD) difference between automatic and manual rotation measurements for the 19 apical images was -0.5 degrees +/- 3.3 degrees for Aaro's method and 0.7 degrees +/- 3.4 degrees for Ho's method. The mean (+/-SD) difference between automatic and manual rotation measurements for the 204 endplate images was 0.25 degrees +/- 3.8 degrees . CONCLUSIONS: The symmetry ratio algorithm allows automatic measurement of vertebral rotation in idiopathic scoliosis without intraobserver or interobserver error due to landmark point selection.

Algorithms↗
PubMed2004

Improving the acceptability of the atrial defibrillator: patient-activated cardioversion versus automatic night cardioversion with and without sedation (ADSAS 2).

Acceptability of the atrial defibrillator is partly limited by concerns about shock related anxiety and discomfort. Sedation and/or automatic cardioversion therapy during sleep may ease shock discomfort and improve patient acceptability. Three atrial cardioversion techniques were compared: patient-activated cardioversion with sedation, automatic night cardioversion with sedation, and automatic night cardioversion without sedation. Sedation was oral midazolam (15 mg). Fifteen patients aged 60 +/- 13 years were assigned each strategy randomly for three consecutive episodes of persistent atrial fibrillation requiring cardioversion. Patients completed questionnaires for multiple parameters immediately and again at 24 hours postcardioversion. Atrial cardioversion strategies with oral sedation (patient-activated and automatic) significantly reduced shock recall by 77% (P < 0.005), therapy dissatisfaction by 57%-71% (P < 0.03), shock discomfort by 61%-73% (P < 0.01), shock pain by 79%-83% (P < 0.001), and shock intensity by 73%-77% (P < 0.03), compared to automatic night cardioversion without sedation (P < 0.02). Atrial shock pain was short-lived and caused little disruption to the patients' daily routines. Automatic night cardioversion without sedation, resulted in sleep disturbances not seen with the other strategies (42% vs 0%, P < 0.001) as well as concerns about future pain or discomfort. Twelve patients (80%) chose patient-activated cardioversion with sedation as their preferred treatment, and three (20%) remainder chose automatic night cardioversion with sedation. Ninety percent of patients chose automatic night cardioversion without sedation as the least acceptable therapy. Sedation significantly increases atrial shock acceptability regardless of cardioversion method. Shocks without sedation are significantly less acceptable to patients using the atrial defibrillators.

Anxiety↗
PubMed2003

Automatic three-dimensional model for protontherapy of the eye: preliminary results.

Recently, radiotherapy possibilities have been dramatically increased by software and hardware developments. Improvements in medical imaging devices have increased the importance of three-dimensional (3D) images as the complete examination of these data by a physician is not possible. Computer techniques are needed to present only the pertinent information for clinical applications. We describe a technique for an automatic 3D reconstruction of the eye and CT scan merging with fundus photographs (retinography). The final result is a "virtual eye" to guide ocular tumor protontherapy. First, we make specific software to automatically detect the position of the eyeball, the optical nerve, and the lens in the CT scan. We obtain a 3D eye reconstruction using this automatic method. Second, we describe the retinography and demonstrate the projection of this modality. Then we combine retinography with a reconstructed eye, using a CT scan to get a virtual eye. The result is a computer 3D scene rendering a virtual eye into a skull reconstruction. The virtual eye can be useful for the simulation, the planning, and the control of ocular tumor protontherapy. It can be adapted to treatment planning to automatically detect eye and organs at risk position. It should be highlighted that all the image processing is fully automatic to allow the reproduction of results, this is a useful property to conduct a consistent clinical validation. The automatic localization of the organ at risk in a CT scan or an MRI by automatic software could be of great interest for radiotherapy in the future for comparison of one patient at different times, the comparison of different treatments centers, the possibility of pooling results of different treatments centers, the automatic generation of doses-volumes histograms, the comparison between different treatment planning for the same patient and the comparison between different patients at the same time. It will also be less time consuming.

Eye↗