In this video with Prof. Hess and Dr. Fleischer, we show you how an endoscopy (laryngoscopy, vocal cord examination) is performed.
Examination methods, diagnostics
Voice disorders can have a variety of causes, which is why accurate diagnosis and selection of the best examination methods are crucial for subsequent treatment.
At the MEDICAL VOICE CENTER (MEVOC), we pay special attention to the examination. The proven method of laryngoscopy provides excellent visualization of the larynx and vocal folds. We use flexible endoscopes to ensure that the procedure is painless. These endoscopes are not only very small, but also extremely high resolution. Only this high-resolution digital video endoscopy with chip-tip optics allows the best possible diagnosis. By using very small endoscopes and computer-controlled HD video technology, even microscopically small changes in the vocal folds can be detected. The MEDICAL VOICE CENTER always uses the latest and most precise procedures and instruments.
Laryngoscopy (endoscopy of the larynx)
These completely painless exams are performed in the chair under light spray anesthesia and provide meaningful information about the tissues and function of the larynx, vocal cords, and resonance chambers of the upper airway in just a few minutes.
Our superior diagnostic procedures with high-resolution visualization
High-resolution video endoscopy with tip-chip cameras, image processing and computer storage can be performed using the latest magnifying laryngoscopes and flexible optics.
These completely painless examinations are performed on the examination chair under light spray anesthesia and provide meaningful findings on the tissue and function of the larynx, vocal folds and resonance chambers of the upper respiratory tract in just a few minutes.
All images are digitized in high resolution and archived without loss of quality for later image comparisons. The MEDICAL VOICE CENTER uses only the latest high-intensity optics and HD imaging systems. High Definition (HD) resolution is the routine standard.
Optical filtering of endoscopic light with contrast of blood vessels and mucosal surface structures enables faster detection and visualization of tissue changes.
NBI can be used with digital video endoscopy to expand the physician’s diagnostic capabilities. Abnormal areas can be detected more quickly, especially in cancer screening.
With more than 2000 recordings per second (!), visualizations of individual vocal fold vibrations can also provide information about unique irregularities in vocal fold vibrations.
Using a magnifying laryngoscope, a video sequence can be recorded without strain and analyzed in offline mode. This makes it possible to detect vibration patterns as the vocal folds vibrate in and out – one of the domains of high-speed glottography compared to standard stroboscopy. A high-speed kymogram can be generated in offline mode.
Videokymography (VKG) allows the simultaneous display of an image of the larynx and analysis of the vibration of the vocal folds during sound production.
Immediate visual assessment with detailed registration of vocal fold movements of each individual vocal fold during opening and closing extends the physician’s diagnosis with immediate findings at the examination site. The physicians at the MEDICAL VOICE CENTER have many years of experience with this method, which is particularly useful in the differential diagnosis of singers.
Painless video endoscopy of the swallowing process using the FEES method (Flexible Endoscopic Examination of Swallowing) allows detailed diagnosis of the individual phases of swallowing and the sensitivity of the pharynx and larynx.
Some voice disorders are accompanied by swallowing disorders. This is often due to the fact that the larynx has a dual function as a voice-producing organ and as a closing organ during swallowing. For this reason, a swallowing evaluation is often combined with a voice evaluation.
Painless transnasal endoscopy of the esophagus (TNE) is recommended in some cases after video endoscopy of the swallowing process.
Like the FEES method of swallowing evaluation, TNE can be performed on an outpatient basis without sedation. Since some voice disorders are associated with dysphagia, this examination can be performed immediately afterwards. This is often due to the fact that the larynx has a dual function as a voice-producing organ and as a closing organ during swallowing.
Painless transnasal endoscopy of the trachea (TNT) is recommended in some cases after video endoscopy of the larynx.
Like videostroboscopy of the vocal cords, TNT can be performed on an outpatient basis without sedation. Because some voice disorders are associated with respiratory problems, this examination is recommended immediately after laryngoscopy. This is sometimes because the larynx and trachea work together as a breathing organ – the airway must be kept open when swallowing or voice production is not taking place.
Electroglottography (EGG) can show the closing of the vocal folds with millisecond precision.
Using two electrodes placed on the neck at the level of the larynx (similar to an EKG), the vibration of the vocal folds can be analyzed with an imperceptible leakage current. If the vibrations are periodic, the fundamental frequency can be accurately calculated. At the same time, the closure pattern of the vocal folds can be seen from the biosignal curve. In the case of hoarse voices, signal analysis of the EGG curve can accurately distinguish between phonation-related and resonance-related disorders.
Today, partial or complete paralysis of the recurrent laryngeal nerve can be specifically evaluated in an outpatient setting using laryngeal electromyography (LEMG).
Restricted movement of the vocal cords is often due to a nerve disorder of the recurrent laryngeal nerve (RLN). At the MEDICAL VOICE CENTER, laryngeal electromyography is performed using the latest generation of EMG equipment. Recordings of all the muscles of the larynx can be made in just a few minutes during an outpatient examination.
Our diagnostic procedures for acoustic voice sound analysis and voice field measurement
In PC-based hoarseness measurement, formant analysis is regularly performed in the spectrogram in addition to the measurement of the sound pressure level, fundamental frequency and deviations in regularity (so-called perturbation measurement).
The most modern methods also analyze the spoken language in addition to the vowels. We often use broadband and narrowband spectral analysis. We have a voice laboratory according to the UEP standard with hoarseness assessment including measurement of interference (jitter, shimmer), signal-to-noise parameters, F0 profile, electroglottography (EGG).
The simultaneous display of the electroglottographic signal (EGG signal) and the power spectrum makes it possible to determine the so-called “speaker formant” and “singer formant”.
It is also a valuable feedback method for the performer to use the voice in a more targeted way. It is also a useful method for gaining clarity about the voice’s ability to penetrate a noisy environment.
Vocal range is an important characteristic of vocal performance. In the case of vocal dysfunctions, e.g. in professional speakers, both the speaking and singing range can be determined. In addition to high and low pitches, both loud and soft pitches are measured under standardized conditions, and sometimes other characteristics are integrated into a third quality dimension and displayed as a 3D graph.
Voice stress tests can be used to create profiles of vocal changes during and after stress with constant parameters of volume (sound pressure level in dB) and fundamental pitch (fundamental frequency).
In the MEDICAL VOICE CENTER, vocal workloads can be tested using scientifically standardized vocal workloads. These “stress tests” increase the diagnostic power, e.g. when assessing occupational demands on the vocal apparatus.
Examination of breathing, voice, resonance, posture and individual voice image by a multidisciplinary team, auditory-perceptual voice analysis (RBH, GRBAS, DSI).
The entire expertise of the speech therapy profession is behind this point. There is an almost unmanageable number of examination methods available, including perceptual, subjective and objective methods of voice analysis. An essential part of this is the many years of personal experience of our staff.
Adapted breathing is essential for efficient use of the voice. At the MEDICAL VOICE CENTER, we have a wide range of measurement methods at our disposal to check the influence of breathing on vocalization.
In addition to the standard pneumotachographic recording of the flow-volume curve, other methods available include the determination of phonation breathing (MPT – maximum phonation time), phonatory quotients and pneumography for special questions.