Clinical Practicability of a Newly Developed Real-time Digital Kymographic System.

BACKGROUND: A digital kymogram shows real images of vocal fold vibration. However, DKG is difficult to use in clinical practice because the recorded image cannot be seen instantaneously after examination, as considerable encoding time is required to visualize a digital kymogram. In addition, frame-by frame analysis should be implemented to evaluate high-speed videoendoscopy data, but is time- and labor-intensive. PURPOSE: The purpose of the study was to validate the clinical practicability of a real-time multislice digital kymographic system developed by the authors. We analyzed the promptness and accuracy of the examination before and after intracordal injections in patients with unilateral vocal fold paralysis. METHODS: To assess the clinical applicability of this system, six patients with unilateral vocal fold paralysis were selected. Real-time DKG was performed before and immediately after intracordal injection. We observed changes in the digital kymogram after the intracordal injection. RESULTS: Using this system, 10 scanning lines and up to five vertical pixel row could be obtained in real time, and the maximum acquisition time for the DKG image was 10 seconds. A digital kymogram of the patients could be instantaneously acquired, and whether the intracordal injection was appropriate or not. CONCLUSION: This article is the first validation study after the development of the real-time multislice digital kymographic system. Our system may be a promising tool in clinical practice for immediate assessment of the vibratory patterns of the vocal cords. More research is necessary for further clinical validation.

Determination of phthalic acid esters in Chinese white spirit using dispersive liquid-liquid microextraction coupled with sweeping ß-cyclodextrin-modified micellar electrokinetic chromatography.

A simple method that consumes low organic solvent is proposed for the analysis of phthalic acid esters in Chinese white spirit using dispersive liquid-liquid microextraction coupled with sweeping-micellar electrokinetic chromatography. Tetrachloromethane and white-spirit-containing ethanol were used as the extraction and dispersing solvents, respectively. The electrophoresis separation buffer was composed of 5 mM ß-cyclodextrin, 50 mM sodium dodecyl sulfate and 25 mM borate buffer (pH 9.2) with 9% acetonitrile, enabling the baseline resolution of the analytes within 13 min. Under the optimum conditions, satisfactory linearities (5-1000 ng/mL, r ≥ 0.9909), good reproducibility (RSD ≤ 6.7% for peak area, and RSD ≤ 2.8% for migration time), low detection limits (0.4-0.8 ng/mL) and acceptable recovery rates (89.6-105.7%) were obtained. The proposed method was successfully applied to 22 Chinese white spirits, and the content of dibutyl phthalate in 55% of the samples exceeded the Specific Migration Limit of 0.3 mg/kg established by the domestic and international regulations.

Three registers in an untrained female singer analyzed by videokymography, strobolaryngoscopy and sound spectrography.

There has been a lack of objective data on the singing voice registers, particularly on the so called "whistle" register, occurring in the top part of the female pitch range, which is accessible only to some singers. This study offers unique strobolaryngoscopic and high-speed (7812.5 imagess) videokymographic data on the vocal fold behavior of an untrained female singer capable of producing three distinct voice qualities, i.e., the chest, head and whistle registers. The sound was documented spectrographically. The transition from chest to head register, accompanied by pitch jumps, occurred around tones B4-C#5 (500-550 Hz) and was found to be associated with a slight decrease in arytenoids adduction, resulting in decrease of the closed quotient. The register shifts from head to whistle, also accompanied by pitch jumps, occurred around tones E5-B5 (670-1000 Hz) without any noticeable changes in arytenoids adduction. Some evidence was found for the vocal tract influence on this transition. The mechanism of the vocal fold vibration in whistle register was found principally similar to that at lower registers: vibrations along the whole glottal length and vertical phase differences (indicated by sharp lateral peaks in videokymography) were seen on the vocal folds up to the highest tone G6 (1590 Hz).

High-speed digital imaging and electroglottography of tracheoesophageal phonation by Amatsu's method.

BACKGROUND: Our previous findings have indicated that the thyropharyngeal muscles form a retropharyngeal prominence during alaryngeal phonation via the TE fistula. This prominence forms a so-called 'neoglottis', which is thought to function as the vibratory source. To better understand the mechanism of TE phonation, we analyzed the vibration of the neoglottis using electroglottography (EGG) and a high-speed digital imaging system. PATIENTS AND METHODS: Two volunteers who use TE phonation for their daily speech communication were subjected to this study. The vibrations of the neoglottis were recorded simultaneously as EGG and high-speed imaging with acoustic signals. RESULTS: The vibrations of the neoglottis, recorded by means of high-speed digital imaging, were exactly synchronized with the waveforms of the acoustic signals and EGG. CONCLUSIONS: These results further confirm the neoglottis as the source of vibration during tracheoesophageal (TE) phonation.

[Physical and technical elements of short-interval, color-filtered double strobe flash-stroboscopy]. / Technisch-physikalische Grundlagen der Doppelbelichtungsstroboskopie.

INTRODUCTION: Quantitative measurement of vocal fold movements can be done either with high-speed imaging or with short interval, color-filtered double strobe flash-stroboscopy. The physical and technical elements of this new technique are described. METHODS: Two special strobe units (KAY Elemetrics RLS 9100) are used in a master-slave configuration. In this way an adjustable interval of 0.1-2.0 ms between flashes is introduced. The strobe flashes are color filtered and are separated by a brief interval. By this means a double exposure is created in each video frame.Real-time visualization of opening and closing velocities over the entire length of the vocal fold from anterior to posterior is possible. Quantification is possible off-line after image calibration. CONCLUSION: Short-interval, color-filtered double-strobe flash stroboscopy allows quantitative measurement of the velocity of vocal fold movements during vibration at different pitches and sound pressure levels (SPL). Images gained with this new technique provide information about a dynamic property (velocity) of the vocal fold within a single image.Therefore, its use could be helpful from the aspect of clinical documentation.

[Noninvasive diagnosis of coronary heart disease with cardiokymography: use of signal averaging technique]. / Nichtinvasive Diagnostik der koronaren Herzerkrankung mit Kardiokymographie: Einsatz der Signalmittelungstechnik.

Regional wall motion abnormality is the best indicator for coronary ischemia. Myocardial wall motion is registrated by cardiokymography (CKG), a mechanocardiographic method. Because of the high incidence of artefacts, echocardiography and nuclear imaging technique have been preferred. Computer-assisted signal averaging CKG improves practicability and allows measurements during exercise testing. Exercise testing was performed in 54 patients with suspected ischemic heart disease without mitral or aortic valve dysfunction, myocardial infarction or prior cardiac surgery. The results of simultaneously recorded ECG and CKG were compared with coronary angiographic results. CKG sensitivity and specificity were higher than that of ECG (76 and 80% vs 71 and 52%). If diagnosis was based on pathological or nonpathological results of both CKG and ECG, sensitivity and negative predictive value increased to 87 and 83%, respectively. Sensitivity reached 93% when only one pathological result was required. CKG combined with signal-averaging techniques has advanced to become a specific and sensitive tool in the non-invasive diagnostic approach to ischemic heart disease.

Continuous postoperative free-flap monitoring with an EKG-interfaced photoplethysmograph.

A compact battery-operated tissue-perfusion monitor has been developed which continuously displays photoplethysmograph waveforms on bedside EKG monitors. The device has been of proven utility in the postoperative monitoring of free-flap recipients.

[Theoretical aspects of the formation of a roentgenokymographic image]. / Teoreticheskie aspekty formirovaniia rentgenokimograficheskogo izobrazheniia.

A procedure for estimating optimal values of parameters for the roentgenokymographic devices, including the basic parameter--the slit width, has been devised. An interrelation between the slit width in ordinary and perspective protective roentenokymographic devices was determined. The optimal slit width in the ordinary roentgenokymographic device was found to equal 0.5+0.03 mm, and in the protected roentgenokymographic device the investigation of adults and children indicated 0.15+0.02 and 0.22+0.02 mm, respectively. The resulting theoretical values are supported by experimental findings.

[Unit for the registration of cinekymograms]. / Ustnoistvo dlia registratsii kinokimogramm.

The principle underlying the action of basic subassemblies of the appliance for registration of kymographic curves from roentgenocinemafilms is described. A comparison of the cinemakymographic method with that of electrokymography is given and advantages of the proposed method are indicated.