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COMMUNIKAY Vol. 4, No. 2
Kay is proud to announce the introduction of the Videokymography (VKG) System, Model 8900, to its family of products. Designed for the direct observation of vocal fold vibratory characteristics, VKG is the ideal complement to stroboscopy. VKG involves the use of a modified video camera (coupled to a standard rigid endoscope and constant light source) which is capable of capturing high-speed motion such as vocal fold vibration. The VKG camera scans a single line at 8000 lines/second, which is recorded to a standard videocassette recorder for review and analysis. Developed in the Groningen Voice Research Lab, Dept. of Medical Physiology, University of Groningen, the Netherlands, by Dr. Harm K. Schutte and Dr. Jan Svec (who is now working at the Centre for Communication Disorders, Postgraduate Medical Institute, Prague, the Czech Republic), the videokymographic technique has been used to evaluate hundreds of patients, therein establishing its clinical value. According to Schutte, videokymographic images reflect important properties of vocal fold vibration, including open and closed phases of the glottal cycle, opening and closing movements, displacements of the upper and lower vocal fold margins, and propagation of mucosal waves. As a result, “both researchers as well as clinicians can benefit from the important information regarding vocal fold dynamics gained using this powerful technique.” The VKG camera offered by Kay functions in either standard, black-and-white composite video mode, or in high-speed mode. In high-speed mode, a single line from the standard image is selected and scanned at nearly 8000 lines/second. “With each line displayed on the monitor in succession,” explains Schutte, “what you see is a time history representing successive glottal cycles.” Clinicians can position the endoscope to “select” which portion of the vocal folds (e.g., middle, anterior commissure, etc.) to observe. Additionally, a convenient foot pedal allows the clinician to easily switch between the standard and high-speed modes. Although the full-screen display of the VKG “image” constituted of single lines is not as intuitive as stroboscopy, VKG does allow direct viewing of vocal fold behaviors which may not be observable with a strobed image. “For example,” says Schutte, “the high scan rate of the VKG system allows the direct observation of vocal fold motion, even if the motion is aperiodic.” Thus, voicing initiation, diplophonia, biphonia, vocal fry, creaky voice, and aperiodicity, all can be viewed directly. Concludes Schutte, “VKG promises to play a key role in broadening the understanding of phonatory dynamics.” For more information about the VKG System, contact Kay or your local representative.
Rion Co., Ltd. has become Kay’s representative for stroboscopy instrumentation sold to medical facilities in Japan. The partnership was signed on July 30, 1997, at Kay’s headquarters in Lincoln Park, NJ. Attending the signing from Rion were Yuzo Gyotoku, president and CEO, and Kiyoshi Ishiyama, business development manager. Established in 1944, Rion is Japan’s foremost designer of hearing aids, as well as other instrumentation used in the fields of audiology, otolaryngology, and speech-language pathology. Notes John Crump, president of Kay Elemetrics, “We are very pleased to form this partnership. Rion not only has an excellent reputation, it also serves markets closely allied to those to which we sell.” Kay’s Computer-Integrated Stroboscopy System was recently approved by Japan’s regulatory agency for medical devices. There are plans to submit the Swallowing Workstation for regulatory approval in Japan later this year.
Van de Heyning, P.H., et al. Functional Assessment of Voice Disorders, ACTA Oto-Rhino-Laryngologica Belgica, Vol. 50, 4th trimester, 1996. This entire issue (147 pages) of the quarterly Belgian ACTA publication is devoted to methodology of voice assessment including videostroboscopic, aerodynamic, acoustic, and perceptual evaluation. Objective results across a wide range of pathologies are reported and interpreted. The issue also contains a detailed summary of data collected by the Belgian Study Group on Voice Disorders. This highly informative issue will be of particular interest to clinicians who specialize in voice. A variety of Kay instrumentation/software was used in these studies. ***** Max, Ludo and Peter B. Mueller. “Speaking F0 and cepstral periodicity analysis of conversational speech in a 105-year-old woman: variability of aging effects.” Journal of Voice, Vol. 10, No. 3, pp. 245-251, 1996. This paper presents the results of acoustical analysis on a 105-year-old female subject. Parameters measured include mean fundamental frequency and cepstrum analysis during conversational speech. The cepstral analysis was used to determine the periodicity of voicing during conversational speech rather than during sustained vowels. Using the data collected, and references in the professional literature on this topic, the authors discuss the effects of aging on voice and the need for clinicians to consider the wide range of population variability. The Computerized Speech Lab (CSLTM) was used for acoustical analysis in this study. ***** Olson, Rolf, et al. “Simultaneous Videoradiography and Pharyngeal Solid State Manometry (Videomanometry) in 25 Nondysphagic Volunteers.” Dysphagia, Vol. 10, No. 4, pp. 36-41, 1995. The authors review the technological advances which permit concurrent acquisition/analysis of videofluoroscopy and manometry (“videomanometry”) using solid state sensors for measuring pressures and timing information in the pharynx and UES. The importance of simultaneous fluoroscopy is stressed to allow the clinician to ascertain sensor position during laryngeal elevation, and more. Data is presented on normal subjects and the authors discuss the clinical value of videomanometry. (Note: See section on application articles using Swallowing Workstation in this issue of CommuniKay.) ***** Miller, Richard. “Energy and Freedom in Singing.” Journal of Singing, Vol. 52, No. 2, pp. 27-30, November/December 1996. Dr. Miller has used acoustic analysis instrumentation as both a research and pedagogical tool applied to the singing voice for a number of years. In this article, he analyzes different singing “modes” (e.g., balanced, pressed, and breathy) using electroglottography and narrowband spectrograms. The analysis of different styles is discussed in relation to desirable singing technique and musical aesthetics. The CSL was used for data acquisition and analysis.
Once again, Kay will be offering a free Nasometer or Visi-Pitch II to one lucky individual at ASHA ’97 in Boston. Why not stop by the Kay booth, Island 903, to register for this annual drawing? If you are an ASHA-certified clinician, simply fill out an entry form to be eligible to win. Should your name be selected, the choice of either the Nasometer or the Visi-Pitch II is yours. What parameter is measured using the nasal cannula on the Swallowing Signals Lab? The nasal cannula is used to display, in real-time, the patient’s respiratory
phase (i.e., inspiration, expiration, and apnea) in relation to swallowing. There is no
unit of measurement (e.g., air volume) associated with this display; rather, it is used
primarily to show the phase at which swallowing is initiated and to observe the
coordination between the patient’s breathing and swallowing. This signal is normally
acquired concurrently with surface EMG (also provided with the Swallowing Signals Lab) so
that the timing between the pharyngeal phase of swallowing and respiration can be
monitored by the patient and clinician. Is there a convenient way to locate patient exams by specific pathologies (e.g., polyps) using our Kay Stroboscopy System? Yes, assuming you have been conscientious about entering this type of data (using
consistent format) in the exam comments field for each exam. With the Computer-Integrated
Stroboscopy System, a file search utility is provided which allows searches based on key
words. To use it, exit to DOS, and type: cd c:\strobe\data\. This will limit your search
to the root directory containing all of your exams (you can make your search more
specific, if desired). To bring up the file find utility, type: filefind (no space); if
that does not evoke the utility, type: ff. One of those commands should work. What file format is used by your Multi-Speech software? Kay would like to thank the many stroboscopy customers who took the time to fill out the questionnaire we mailed this summer. We appreciated your compliments as well as your comments on how we can improve our products and services. The winner of the S-VHS VCR raffle was Dr. James M. Campbell, Suburban Voice Specialists, Skokie, IL. Congratulations, Dr. Campbell!
Measuring Tremor The Computerized Speech Lab (CSL) has two software options that contain tremor measurements automatically computed on sustained phonation: the Multi-Dimensional Voice Program (MDVP) and Motor Speech Profile (MSP). The manner in which these programs measure tremor reflects their usage with different clinical populations. To avoid confusion, these tremor measurements have different names. MDVP contains the Amplitude Tremor Intensity Index (ATRI) and the Frequency Tremor Intensity Index (FTRI); these are most sensitive to tremor which is periodic. For example, the vibrato of a trained singer sustaining a sung note contains quasi-periodic frequency and amplitude fluctuations which can be detected and measured using FTRI and ATRI. MDVP also computes the “dominant” frequency in these detected fluctuations. Tremor that is not highly periodic can also be detected within MDVP using the smoothed Pitch Perturbation Quotient (sPPQ) and the smoothed Amplitude Perturbation Quotient (sAPQ). These extraction methods are based on long-term frequency and amplitude perturbation calculations in which smoothing is used over a large window sample (e.g., 50 or more cycles). MSP contains parameters called Magnitude of Amplitude Tremor (MATR) and Magnitude of Frequency Tremor (MFTR) which are calculated using methods similar to sAPQ and sPPQ. Both are sensitive to periodic and aperiodic tremor. MSP also measures the periodicity of the tremor (calculated as a percent) using the Periodicity of Frequency Tremor (Pftr) and Periodicity of Amplitude Tremor (Patr). In these measurements, a perfectly regular tremor would yield a value of 100%. Each method of measuring tremor has clinical validity, but the different approaches should be understood especially by CSL users who have both software programs.
Swallowing Workstation UpdatesApplication Notes AvailableKay has collected a series of application notes and articles on how speech-language pathologists and physicians can use the Swallowing Workstation (or one of its modules) for assessing and treating dysphagic patients. They are available free upon request. Application Notes “Swallowing Evaluation Treatment: Efficiency, Accuracy and Objectivity.” Bonnie Martin-Harris, Program Director, Evelyn Trammel Voice and Swallowing Center, Saint Joseph’s Hospital, Atlanta, GA. “Information about the FEESsm Procedure.” Susan Langmore, VA Medical Center, Speech/Audiology Department, Ann Arbor, MI. “Maximizing Rehabilitative Efforts for Dysphagia Recovery: sEMG Biofeedback Monitoring.” Maggie Lee Huckabee, University of Memphis, Memphis, TN. “Pharyngeal Manofluorography (Video-manometry): A Simple Quantification of the Modified Barium Swallow.” John R. Salassa, Asst. Professor, Dept. of Otolaryngology-Head & Neck Surgery, Mayo Clinic, Jacksonville, FL. “Simultaneous Data Acquisition in Multiple Modalities: Videofluoroscopy, EMG and Tongue Pressure.” JoAnne Robbins, Ph.D., Director, Swallowing Center, UW Hospital and Clinics; Associate Professor, Dept Medicine, Univ.of Wisconsin-Madison, and Associate Director Research, Geriatric Research, Education, and Clinic Center, Wm. S. Middleton Memorial VA Hospital, Madison, WI. Journal Articles “Fiberoptic Endoscopic Examination of Swallowing Safety: A New Procedure.” Susan Langmore et al. Dysphagia Vol. 2, pp. 216-219, 1988. “Coordination between respiration and swallowing: respiratory phase relationships and temporal integration.” Bonnie Martin et al., Journal of Applied Physiology, Vol. 76 (2), pp. 714-723, 1994. Version 2.0 Software ReleasedKay has released a new version of software for the Swallowing Workstation which provides a number of new exciting features. These include: automatically extracted measurements within the waveform data, annotation of video images, and a report generator that summarizes quantitative data collected from the video or waveform data. Call a Product Specialist for more information. Swallowing Signals Lab FlierA new flier describing the Swallowing Signals Lab, a module of the Swallowing Workstation, is now available. This instrument, which can be purchased separately, is ideally suited as a therapy tool. It includes two channels of sEMG, a respiration channel, tongue pressure array, cervical auscultation channel, pharyngeal manometer (optional), and two auxiliary channels. Call to receive your copy. Please look for Kay products on display at the following conferences, workshops, and congresses. Conferences
Workshops
World Congresses
New Stroboscopy Videotape Available Kay has recently produced an educational videotape, titled Video Laryngeal Stroboscopy, that is now available free of charge (one per department) simply by contacting the company. This unique resource was created for otolaryngologists, speech-language pathologists, voice scientists, and teachers to help them learn more about laryngeal stroboscopy. The videotape is divided into three sections. The first section explains the science of stroboscopy, the components of a laryngeal stroboscopy system, rigid versus flexible endoscopy, and pitch tracking issues. This section also demonstrates how stroboscopy reveals critical aspects of vocal fold dynamics. Section two employs a variety of clinical examples from more than 30 examinations to illustrate the appropriate clinical role of stroboscopy as well as its limitations. The examinations used were gathered from leading voice centers and serve to show the diagnostic capabilities and therapy applications of video laryngeal stroboscopy. The final section contains a brief demonstration of the Kay RLS Videostroboscopy System. With its bright, clear images, this powerful system sets the standard for laryngeal endoscopic and stroboscopic viewing, thereby facilitating accurate and early diagnosis of laryngeal disorders. Advanced features found in the computer-integrated system, such as on-screen annotation of images, easy archiving of patient exams, computer control of camera settings, image digitization, and more, are also discussed here. To order your copy of Video Laryngeal Stroboscopy, contact Kay or your local representative, and be sure to specify whether you need the PAL or NTSC version. |
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