Accuracy of Measurements on Digital Videostroboscopic Images of the Vocal Folds

2005 ◽  
Vol 114 (6) ◽  
pp. 443-450 ◽  
Author(s):  
Renée Speyer ◽  
George H. Wieneke ◽  
Willem Kersing ◽  
Philippe H. Dejonckere
Keyword(s):  
Vocal Folds ◽  
The Real ◽  
Objective Measurements ◽  
Surface Areas ◽  
Accuracy Of Measurements ◽  
Magnification Ratio ◽  
Maximal Opening ◽  
Error Of Measurement ◽  
Boundary Correction

Objectives: The reliability of objective measurements on digital laryngeal images was investigated. Methods: The magnitude of the error of measurement of surface areas by visually tracing the outline was determined for three different areas: the area of the lesion and, during vibration, the glottal area on maximal opening of the vocal folds and the glottal area on maximal closing of the vocal folds. Results: The errors in these areas were 10% to 30%. The results suggest that the error is mainly due to the uncertainty of the real outline of areas with a vague boundary. Correction for differences in magnification between two images (posttherapy and pretherapy) is of importance in about 25% to 65% of cases, depending on the area measured. Conclusions: Only when the magnification ratio is small (less than about ±10% from 1.0) may a correction not be necessary.

Effects of Voice Therapy as Objectively Evaluated by Digitized Laryngeal Stroboscopic Imaging

2002 ◽  
Vol 111 (10) ◽  
pp. 902-908 ◽  
Author(s):  
Renée Speyer ◽  
Pieter A. Kempen ◽  
George Wieneke ◽  
Willem Kersing ◽  
Elham Ghazi Hosseini ◽  
...  
Keyword(s):  
Vocal Fold ◽  
Vocal Folds ◽  
Lesion Size ◽  
Voice Therapy ◽  
Benign Lesions ◽  
Objective Measurements ◽  
Significant Parameter ◽  
Surface Areas ◽  
Vocal Fold Vibration ◽  
Maximal Opening

Objective measurements derived from digitized laryngeal stroboscopic images were used to demonstrate changes in vocal fold vibration and in the size of benign lesions after 3 months of voice therapy. Forty chronically dysphonic patients were studied. By means of a rigid stroboscope, pretreatment and posttreatment recordings were made of the vocal folds at rest and under stroboscopic light during phonation. From each recording, images of the positions at rest and during vibration at maximal opening and at maximal closure were digitized. The surface areas of any lesions and of the glottal gap were independently measured in the digitized images by 2 experienced laryngologists. Referential distances were determined in order to compensate for discrepancies in magnification in the various recordings. After 3 months of voice therapy, significant improvement in lesion size and degree of maximal closure during vibration could be demonstrated in about 50% of the patients. The degree of maximal opening did not prove to be a significant parameter.

scholarly journals Fidedignidade, um enfoque estatístico

1982 ◽  
Vol 4 (4) ◽  
pp. 27
Author(s):  
Maria Emília Camargo ◽  
José Elias Rigueira
Keyword(s):  
Physical Education ◽  
Reliability Theory ◽  
Total Variance ◽  
Measurement Reliability ◽  
The Real ◽  
Time Control ◽  
Error Of Measurement

Reliability is defined as error of measurement. Reliability theory is described and a model is proposed that divides the total variance in two parts: the variance due to error and the real variance.The method of Split-half is described and to determine the reliability of the instrument “Deslizador Manual” used for time control in the area of Physical Education.

Effect of Pelvic Tilt on Radiographic Migration and Wear Measurements after Total Hip Arthroplasty

1998 ◽  
Vol 8 (1) ◽  
pp. 16-23 ◽  
Author(s):  
T. Ilchmann ◽  
U. Kesteris ◽  
H. Wingstrand
Keyword(s):  
Total Hip Arthroplasty ◽  
Hip Arthroplasty ◽  
Pelvic Tilt ◽  
Three Dimensional ◽  
Maximum Error ◽  
Total Hip ◽  
Radiographic Measurements ◽  
Accuracy Of Measurements ◽  
Set Up ◽  
Error Of Measurement

Tilt effects on radiographic measurements after total hip arthroplasty should be studied. A new computerized method for measurement, called EBRA, making three-dimensional calculations and intended to identify tilted radiographs was evaluated for its clinical usefulness. In an experimental set-up repeated radiographs were taken with a human pelvis tilted gradually around its horizontal and vertical axes. Migration and wear were measured with the EBRA method and the results were compared with those made using standard methods. Tilted radiographs were identified and excluded from analysis by the EBRA method, significantly reducing the maximum error of measurement. A systematic error of measurement was found in the presence of consecutively changing tilt in a single direction. Wear measurements were only slightly affected by pelvic tilt. A pelvic tilt can cause considerable errors in the measurement of cup migration-i.e. up to 8.2 mm. The EBRA method improves the accuracy of measurements by taking the effects of tilt into account.

A discussion on the origin and treatment of noise in industrial environments - II. Social effects of noise Noise and the householder

1968 ◽  
Vol 263 (1142) ◽  
pp. 291-297 ◽  
Keyword(s):  
Hearing Loss ◽  
Emotional Reactions ◽  
International Standards ◽  
Social Effects ◽  
Previous Experience ◽  
Industrial Noise ◽  
The Real ◽  
Objective Measurements ◽  
The Past ◽  
International Standards Organization

To the householder, noise is important mainly in respect of its capacity to annoy. Rarely in residential noise problems arising from industry are we concerned with levels which are sufficiently high to interfere with communication or to cause deafness. It is this fact that makes assessment of the intrusive value of industrial noise extremely difficult. One can make objective measurements of hearing loss, or of interference with communication, but one cannot describe, in objective terms, the emotional reactions to noise of people enjoying the privacy of their homes. The problem, therefore, is to decide how we can express the intrusive propensities of a noise in terms of its physically describable characteristics. It might be argued that previous experience is the real guide that is, a survey of noises which people have found to be acceptable in the past, which can be used to predict reaction in new cases. This is, in fact, the basis of criteria of acceptability as assessed by such methods as those currently proposed by the Wilson Committee on the Problem of Noise (1963), and the International Standards Organization; and, indeed, one finds that for noise from traffic, aircraft, and (apart from some extreme examples) noise from

Large-scale Motion of Solar Filaments

2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll
Keyword(s):  
Magnetic Flux ◽  
Proper Motion ◽  
Time Scale ◽  
Large Scale ◽  
Accuracy Of Measurements ◽  
Solar Filaments ◽  
General Movement ◽  
Scale Motion ◽  
Velocity Scatter

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

Cerebral Tissue Response in Chronic Electrode Implantation

1977 ◽  
Vol 35 ◽  
pp. 624-625
Author(s):  
R.F. Dodson ◽  
L.W-F Chu ◽  
N. Ishihara
Keyword(s):  
Tissue Response ◽  
Whole Body ◽  
Platinum Electrodes ◽  
Fixed Tissue ◽  
Electrode Implantation ◽  
Surface Areas ◽  
Tissue Changes ◽  
Micron Diameter ◽  
Extent Of Damage ◽  
Electrode Sheath

The extent of damage surrounding an implanted electrode in the cerebral cortex is a question of significant importance with regard to attaining consistency and validity of physiological recordings. In order to determine the extent of such tissue changes, 150 micron diameter platinum electrodes were implanted in the cortex of four adult baboons, and after eight days the animals were sacrificed by whole body perfusion with a 3% glutaraldehyde in 0.1M phosphate fixative.The calvarium was carefully removed and the electrode tracts were readily discernible in the firm, glutaraldehyde fixed tissue.Careful dissection of the zone of the electrode tract resulted in a small block which was further sectioned into tip, mid-tract and surface areas. Ultrastructurally, damage extended from the electrode sheath to the greatest extent of from 0.2 to 3.5 mm.

Tissue section lifting for electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 86-87
Author(s):  
Adrian F. van Dellen
Keyword(s):  
Infectious Disease ◽  
Electron Microscopy ◽  
Tissue Culture ◽  
Organ System ◽  
Surrounding Tissue ◽  
Paraffin Sections ◽  
Surface Areas ◽  
Specific Determination ◽  
High Degree ◽  
Accuracy And Repeatability

The morphologic pathologist may require information on the ultrastructure of a non-specific lesion seen under the light microscope before he can make a specific determination. Such lesions, when caused by infectious disease agents, may be sparsely distributed in any organ system. Tissue culture systems, too, may only have widely dispersed foci suitable for ultrastructural study. In these situations, when only a few, small foci in large tissue areas are useful for electron microscopy, it is advantageous to employ a methodology which rapidly selects a single tissue focus that is expected to yield beneficial ultrastructural data from amongst the surrounding tissue. This is in essence what "LIFTING" accomplishes. We have developed LIFTING to a high degree of accuracy and repeatability utilizing the Microlift (Fig 1), and have successfully applied it to tissue culture monolayers, histologic paraffin sections, and tissue blocks with large surface areas that had been initially fixed for either light or electron microscopy.

In situ REM imaging of surface processes on ceramic bulk crystals from 300 to 1670 K in a conventional TEM

1991 ◽  
Vol 49 ◽  
pp. 660-661
Author(s):  
Z. L. Wang ◽  
J. Bentley
Keyword(s):  
High Temperatures ◽  
Image Resolution ◽  
Atomic Processes ◽  
Crystal Surfaces ◽  
Beam Radiation ◽  
Surface Areas ◽  
Transmission Electron ◽  
Reflection Electron Microscopy ◽  
Gas Reactions

Studying the behavior of surfaces at high temperatures is of great importance for understanding the properties of ceramics and associated surface-gas reactions. Atomic processes occurring on bulk crystal surfaces at high temperatures can be recorded by reflection electron microscopy (REM) in a conventional transmission electron microscope (TEM) with relatively high resolution, because REM is especially sensitive to atomic-height steps.Improved REM image resolution with a FEG: Cleaved surfaces of a-alumina (012) exhibit atomic flatness with steps of height about 5 Å, determined by reference to a screw (or near screw) dislocation with a presumed Burgers vector of b = (1/3)<012> (see Fig. 1). Steps of heights less than about 0.8 Å can be clearly resolved only with a field emission gun (FEG) (Fig. 2). The small steps are formed by the surface oscillating between the closely packed O and Al stacking layers. The bands of dark contrast (Fig. 2b) are the result of beam radiation damage to surface areas initially terminated with O ions.

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