Articulatory and acoustic differences between lyric and dramatic singing in Western classical music.

Within the realm of voice classification, singers could be sub-categorized by the weight of their repertoire, the so-called "singer's Fach." However, the opposite pole terms "lyric" and "dramatic" singing are not yet well defined by their acoustic and articulatory characteristics. Nine professional singers of different singers' Fach were asked to sing a diatonic scale on the vowel /a/, first in what the singers considered as lyric and second in what they considered as dramatic. Image recording was performed using real time magnetic resonance imaging (MRI) with 25 frames/s, and the audio signal was recorded via an optical microphone system. Analysis was performed with regard to sound pressure level (SPL), vibrato amplitude, and frequency and resonance frequencies as well as articulatory settings of the vocal tract. The analysis revealed three primary differences between dramatic and lyric singing: Dramatic singing was associated with greater SPL and greater vibrato amplitude and frequency as well as lower resonance frequencies. The higher SPL is an indication of voice source changes, and the lower resonance frequencies are probably caused by the lower larynx position. However, all these strategies showed a considerable individual variability. The singers' Fach might contribute to perceptual differences even for the same singer with regard to the respective repertoire.

Soluble urokinase plasminogen activator receptor and survival in elective cardiac surgery.

BACKGROUND: The study investigated the prognostic value of soluble urokinase plasminogen activator receptor (suPAR) in patients undergoing cardiac surgery and calculated a simplified biomarker score comprising suPAR, N-terminal pro B-type natriuretic peptide (NT-proBNP) and age. METHODS AND RESULTS: Biomarkers were assessed in a cohort of 478 patients undergoing elective cardiac surgery. After a median follow-up of 4.2 years, a total of 72 (15.1%) patients died. SuPAR, NT-proBNP and age were independent prognosticators of mortality in a multivariable Cox regression model after adjustment for EuroScoreII. We then calculated a simplified biomarker score comprising age, suPAR and NT-proBNP, which had a superior prognostic value compared to EuroScoreII (Harrel's C of 0.76 vs. 0.72; P for difference = 0.02). Besides long-term mortality, the biomarker score had an excellent performance predicting one-year mortality and hospitalization due to heart failure. CONCLUSION: The biomarker suPAR and NT-proBNP were strongly and independently associated with mortality in patients undergoing cardiac surgery. A simplified biomarker score comprising only three variables (age, suPAR and NT-proBNP) performed better than the established EuroScoreII with respect to intermediate and long-term outcome as well as hospitalization due to heart failure. As such, integration of established and upcoming biomarkers in clinical practice may provide improved decision support in cardiac surgery.

A coupled experimental and statistical approach for an assessment of SARS-CoV-2 infection risk at indoor event locations.

Indoor event locations are particularly affected by the SARS-CoV-2 pandemic. At large venues, only incomplete risk assessments exist, whereby no suitable measures can be derived. In this study, a physical and data-driven statistical model for a comprehensive infection risk assessment has been developed. At venues displacement ventilation concepts are often implemented. Here simplified theoretical assumptions fail for the prediction of relevant airflows for airborne transmission processes. Thus, with locally resolving trace gas measurements infection risks are computed more detailed. Coupled with epidemiological data such as incidences, vaccination rates, test sensitivities, and audience characteristics such as masks and age distribution, predictions of new infections (mean), situational R-values (mean), and individual risks on- and off-seat can be achieved for the first time. Using the Stuttgart State Opera as an example, the functioning of the model and its plausibility are tested and a sensitivity analysis is performed with regard to masks and tests. Besides a reference scenario on 2022-11-29, a maximum safety scenario with an obligation of FFP2 masks and rapid antigen tests as well as a minimum safety scenario without masks and tests are investigated. For these scenarios the new infections (mean) are 10.6, 0.25 and 13.0, respectively. The situational R-values (mean) - number of new infections caused by a single infectious person in a certain situation - are 2.75, 0.32 and 3.39, respectively. Besides these results a clustered consideration divided by age, masks and whether infections occur on-seat or off-seat are presented. In conclusion this provides an instrument that can enable policymakers and operators to take appropriate measures to control pandemics despite ongoing mass gathering events.

Dynamic changes of vocal tract dimensions with sound pressure level during messa di vocea).

The messa di voce (MdV), which consists of a continuous crescendo and subsequent decrescendo on one pitch is one of the more difficult exercises of the technical repertoire of Western classical singing. With rising lung pressure, regulatory adjustments both on the level of the glottis and the vocal tract are required to keep the pitch stable. The dynamic changes of vocal tract dimensions with the bidirectional variation of sound pressure level (SPL) during MdV were analyzed by two-dimensional real-time magnetic resonance imaging (25 frames/s) and synchronous audio recordings in 12 professional singer subjects. Close associations in the respective articulatory kinetics were found between SPL and lip opening, jaw opening, pharynx width, uvula elevation, and vertical larynx position. However, changes in vocal tract dimensions during plateaus of SPL suggest that perceived loudness could have been varied beyond the dimension of SPL. Further multimodal investigation, including the analysis of sound spectra, is needed for a better understanding of the role of vocal tract resonances in the control of vocal loudness in human phonation.

Coronavirus vaccination rates in cultural areas in Germany.

Vaccination is a significant preventive measure to contain the coronavirus disease-2019 (COVID-19) pandemic. Vaccination rates can provide useful information on the potential spread of infection in a given population. In this study, vaccination rates and attitudes towards vaccination in cultural sectors, specifically the music sector, have been investigated. In total, 4341 persons in four different areas, including visitors to performances of classical music and musicals, as well as professional and amateur musicians, have participated in this survey. Results show rates of 86% recovered from the COVID-19 virus or vaccinated at least once, with 54.5% fully vaccinated. These vaccination rates were considerably higher compared to the general population. An attitude of hesitation towards vaccination found in 6.4% of those sampled was half that of the general population. These findings drawn from a large sample indicate that in the field of music a high vaccination rate is to be found, as well as a low rejection rate of vaccination on the part of the audience and performers. The results can be used to provide insights into the vaccination status to be found at cultural events and, importantly, to assist in consideration of whether cultural events should be permitted to continue under pandemic circumstances.

Prescription Patterns of Sodium-Glucose Cotransporter 2 Inhibitors and Cardiovascular Outcomes in Patients with Diabetes Mellitus and Heart Failure.

PURPOSE: The benefit of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in patients with heart failure (HF) with reduced ejection fraction (HFrEF) and type 2 diabetes mellitus (T2DM) has been unequivocally proven in randomized, controlled trials. However, real-world evidence assessing the implementation of SGLT2i in clinical practice and their benefit in HF outside of highly selected study populations is limited. METHODS: Patients with HF and T2DM admitted to the cardiology ward of the Medical University of Vienna between 01/2014 and 04/2020 were included in the present analysis. All first-time prescriptions of SGLT2i were identified. The outcome of interest was cardiovascular mortality. The median follow-up time was 2.3 years. RESULTS: Out of 812 patients with T2DM and HF (median age 70.4 [IQR 62.4-76.9] years; 70.3% males), 17.3% received an SGLT2i. The frequency of SGLT2i prescriptions significantly increased over the past 6 years (+ 36.6%, p < 0.001). In propensity score-adjusted pairwise analyses, SGLT2i treatment was inversely associated with long-term cardiovascular mortality in patients with HFrEF presenting with an adjusted HR of 0.33 (95%CI: 0.13-0.86; p = 0.024). CONCLUSION: Despite large outcome trials showing a cardiovascular benefit, SGLT2i remain underutilized in clinical practice in patients with T2DM and HF. National and European Medical Agency remuneration regulations would allow more patients at high risk to receive these cardiovascular protective drugs. Most importantly, an SGLT2i therapy was associated with a survival benefit in patients with HFrEF.

Sub-millisecond 2D MRI of the vocal fold oscillation using single-point imaging with rapid encoding.

OBJECTIVE: The slow spatial encoding of MRI has precluded its application to rapid physiologic motion in the past. The purpose of this study is to introduce a new fast acquisition method and to demonstrate feasibility of encoding rapid two-dimensional motion of human vocal folds with sub-millisecond resolution. METHOD: In our previous work, we achieved high temporal resolution by applying a rapidly switched phase encoding gradient along the direction of motion. In this work, we extend phase encoding to the second image direction by using single-point imaging with rapid encoding (SPIRE) to image the two-dimensional vocal fold oscillation in the coronal view. Image data were gated using electroglottography (EGG) and motion corrected. An iterative reconstruction with a total variation (TV) constraint was used and the sequence was also simulated using a motion phantom. RESULTS: Dynamic images of the vocal folds during phonation at pitches of 150 and 165 Hz were acquired in two volunteers and the periodic motion of the vocal folds at a temporal resolution of about 600 µs was shown. The simulations emphasize the necessity of SPIRE for two-dimensional motion encoding. DISCUSSION: SPIRE is a new MRI method to image rapidly oscillating structures and for the first time provides dynamic images of the vocal folds oscillations in the coronal plane.

The spread of breathing air from wind instruments and singers using schlieren techniques.

The spread of breathing air when playing wind instruments and singing was investigated and visualized using two methods: (1) schlieren imaging with a schlieren mirror and (2) background-oriented schlieren (BOS). These methods visualize airflow by visualizing density gradients in transparent media. The playing of professional woodwind and brass instrument players, as well as professional classical trained singers were investigated to estimate the spread distances of the breathing air. For a better comparison and consistent measurement series, a single high note, a single low note, and an extract of a musical piece were investigated. Additionally, anemometry was used to determine the velocity of the spreading breathing air and the extent to which it was quantifiable. The results showed that the ejected airflow from the examined instruments and singers did not exceed a spreading range of 1.2 m into the room. However, differences in the various instruments have to be considered to assess properly the spread of the breathing air. The findings discussed below help to estimate the risk of cross-infection for wind instrument players and singers and to develop efficacious safety precautions, which is essential during critical health periods such as the current COVID-19 pandemic.

Investigation of resonance strategies of high pitch singing sopranos using dynamic three-dimensional magnetic resonance imaging.

Resonance-strategies with respect to vocal registers, i.e., frequency-ranges of uniform, demarcated voice quality, for the highest part of the female voice are still not completely understood. The first and second vocal tract resonances usually determine vowels. If the fundamental frequency exceeds the vowel-shaping resonance frequencies of speech, vocal tract resonances are tuned to voice source partials. It has not yet been clarified if such tuning is applicable for the entire voice-range, particularly for the top pitches. We investigated professional sopranos who regularly sing pitches above C6 (1047 Hz). Dynamic three-dimensional (3D) magnetic resonance imaging was used to calculate resonances for pitches from C5 (523 Hz) to C7 (2093 Hz) with different vowel configurations ([a:], [i:], [u:]), and different contexts (scales or octave jumps). A spectral analysis and an acoustic analysis of 3D-printed vocal tract models were conducted. The results suggest that there is no exclusive register-defining resonance-strategy. The intersection of fundamental frequency and first vocal tract resonance was not found to necessarily indicate a register shift. The articulators and the vocal tract resonances were either kept without significant adjustments, or the fR1:fo-tuning, wherein the first vocal tract resonance enhances the fundamental frequency, was applied until F6 (1396 Hz). An fR2:fo-tuning was not observed.

Magnetic resonance imaging of the vocal fold oscillations with sub-millisecond temporal resolution.

PURPOSE: The temporal resolution of the MRI acquisition is intrinsically limited by the duration of the spatial encoding, which is typically on the order of milliseconds. Faster motion such as the vibration of the vocal folds during phonation cannot be imaged with conventional MRI as this would require sampling frequencies in the kilo-Hertz range. Here, a faster MRI acquisition strategy is presented that encodes a 1D periodic motion at a temporal resolution that is an order of magnitude higher compared to conventional MRI. METHODS: The proposed method encodes the position of an object moving along 1 dimension by applying very short phase encoding gradients along the same direction. This reduces the temporal resolution from the repetition time (TR) to the duration of the phase encoding gradients, which in this work was well below 1 ms. The technique is applied to the vocal fold oscillations and the position of the vocal folds is measured simultaneously using electroglottography (EGG). Simulations of the point spread function for regular encoding and the proposed method are performed as well. RESULTS: With this new phase, encoding strategy oscillations of the human vocal folds up to a frequency of 145 Hz could be dynamically imaged at 10 images per cycle. Simulations show the advantage of this method over conventional imaging of fast moving objects. CONCLUSION: A new method for MR imaging of fast moving spins is presented allowing a temporal resolution below 1 ms at a spatial resolution below 1 mm, circumventing TR as the limit for temporal resolution.

The Prognostic Impact of Circulating Regulatory T Lymphocytes on Mortality in Patients with Ischemic Heart Failure with Reduced Ejection Fraction.

BACKGROUND: Heart failure with reduced ejection fraction (HFrEF) constitutes a global health issue. While proinflammatory cytokines proved to have a pivotal role in the development and progression of HFrEF, less attention has been paid to the cellular immunity. Regulatory T lymphocytes (Tregs) seem to have an important role in the induction and maintenance of immune homeostasis. Therefore, we aimed to investigate the impact of Tregs on the outcome in HFrEF. METHODS: We prospectively enrolled 112 patients with HFrEF and performed flow cytometry for cell phenotyping. Individuals were stratified in ischemic (iHFrEF, n = 57) and nonischemic etiology (niHFrEF, n = 57) and nonischemic etiology (niHFrEF. RESULTS: Comparing patients with iHFrEF to niHFrEF, we found a significantly lower fraction of Tregs within lymphocytes in the ischemic subgroup (0.42% vs. 0.56%; p = 0.009). After a mean follow-up time of 4.5 years, 32 (28.6%) patients died due to cardiovascular causes. We found that Tregs were significantly associated with cardiovascular survival in the entire study cohort with an adjusted HR per one standard deviation (1-SD) of 0.60 (95% CI: 0.39-0.92; p = 0.009). After a mean follow-up time of 4.5 years, 32 (28.6%) patients died due to cardiovascular causes. We found that Tregs were significantly associated with cardiovascular survival in the entire study cohort with an adjusted HR per one standard deviation (1-SD) of 0.60 (95% CI: 0.39-0.92; p = 0.009). After a mean follow-up time of 4.5 years, 32 (28.6%) patients died due to cardiovascular causes. We found that Tregs were significantly associated with cardiovascular survival in the entire study cohort with an adjusted HR per one standard deviation (1-SD) of 0.60 (95% CI: 0.39-0.92; p = 0.009). After a mean follow-up time of 4.5 years, 32 (28.6%) patients died due to cardiovascular causes. We found that Tregs were significantly associated with cardiovascular survival in the entire study cohort with an adjusted HR per one standard deviation (1-SD) of 0.60 (95% CI: 0.39-0.92. CONCLUSION: Our results indicate a potential influence of Tregs in the pathogenesis and progression of iHFrEF, fostering the implication of cellular immunity in iHFrEF pathophysiology and proving Tregs as a predictor for long-term survival among iHFrEF patients. A preview of this study has been presented at a meeting of the European Society of Cardiology earlier this year.

The impact of a standardized vocal loading test on vocal fold oscillations.

INTRODUCTION: Vocal loading capacity is an important aspect of vocal health and is measured using standardized vocal loading tests. However, it remains unclear how vocal fold oscillation patterns are influenced by a standardized vocal loading task. METHODS: 21 (10 male, 11 female) vocally healthy subjects were analyzed concerning the dysphonia severity index (DSI) and high speed videolaryngoscopy (HSV) on the vowel /i/ at a comfortable pitch and loudness before and after a standardized vocal loading test (10 min standardized text reading, at a level higher than 80 dB (A) measured at 30 cm from the mouth). RESULTS: Changes in DSI were statistically significant, diminishing by 1.2 points after the vocal loading test, which was mainly caused by an increase of the minimum intensity. However, the pre-post comparison of HSV derived measures failed to show any statistically significant changes. CONCLUSION: It seems necessary to analyze the effects of a standardized vocal loading test on vocal fold oscillation patterns with respect to softest phonation and phonation threshold pressure rather than comfortable pitch and loudness. Level of evidence 2c.

Immediate effects of water resistance therapy on patients with vocal fold mass lesions.

INTRODUCTION: Semi-occluded vocal tract exercises, such as water resistance therapy (WRT), are widely used in voice therapy. However, the potential positive effects of such a therapy on vocal fold oscillation patterns in patients indicating a need for phonomicrosurgery have not yet been explored. The presented study aims to analyze the effect of WRT in patients suffering from vocal fold mass lesions. MATERIALS AND METHODS: Eight participants with vocal fold mass lesions were asked to sustain a phonation on the vowel /i/ at a comfortable loudness and a fundamental frequency of 250 Hz (females) or 125 Hz (males). During phonation the subjects were simultaneously recorded with transnasal high-speed videoendoscopy (HSV, 20.000 fps), electroglottography, and audio signals. These subjects then performed a WRT (phonation in a silicone tube of 30 cm length, 5 cm below the water surface) for 10 min. Repeated measurements of sustained phonation were performed 0, 10, and 30 min after exercising. From the HSV data the glottal area waveform (GAW) was segmented and GAW parameters were computed. RESULTS: During WRT there was an increase of the GAW related open quotient and closing quotient. Immediately after WRT, there was a drop of both values followed by a rise of these parameters up to 30 min after the intervention. Furthermore, there was no correlation between GAW and electroglottographical open quotients. CONCLUSIONS: The effects observed after a single session of WRT on participants with vocal fold mass lesions showed a similar pattern to vocal fatigue.

[An across-scales analysis of the voice self-concept questionnaire (FESS)]. / Skalenübergreifende Auswertung des Fragebogens zur Erfassung des stimmlichen Selbstkonzepts (FESS).

BACKGROUND: The questionnaire for the assessment of the voice selfconcept (FESS) contains three sub-scales indicating the personal relation with the own voice. The scales address the relationship with one's own voice, the awareness of the use of one's own voice, and the perception of the connection between voice and emotional changes. A comprehensive approach across the three scales supporting a simplified interpretation of the results was still missing. MATERIAL AND METHOD: The FESS questionnaire was used in a sample of 536 German teachers. With a discrimination analysis, commonalities in the scale characteristics were investigated. For a comparative validation with voice health and psychological and physiological wellbeing, the Voice Handicap Index (VHI), the questionnaire for Work-related Behavior and Experience Patterns (AVEM), and the questionnaire for Health-related Quality of Life (SF-12) were additionally collected. RESULTS: The analysis provided four different groups of voice self-concept: group 1 with healthy values in the voice self-concept and wellbeing scales, group 2 with a low voice self-concept and mean wellbeing values, group 3 with a high awareness of the voice use and mean wellbeing values and group 4 with low values in all scales. CONCLUSION: The results show that a combined approach across all scales of the questionnaire for the assessment of the voice self-concept enables a more detailed interpretation of the characteristics in the voice self-concept. The presented groups provide an applicable use supporting medical diagnoses.

Risk of arrhythmic death in ischemic heart disease: a prospective, controlled, observer-blind risk stratification over 10 years.

BACKGROUND: Risk of arrhythmic death is considered highest in ischemic heart disease with severe left ventricular ejection fraction (LVEF) reduction. Non-invasive testing should improve decision-making of prophylactic defibrillator (ICD) implantation. DESIGN: We enrolled 120 patients with ischemic heart disease and LVEF < 50% and 30 control subjects without ischemic heart disease and normal LVEF. An initial assessment, a second assessment after 3 years and a final follow-up comprised of pharmacological baroreflex testing (BRS), short-term spectral [low-frequency (LF) to high-frequency (HF) ratio] and long-term time-domain analysis of heart rate variability (SDNN), exercise Microvolt T-wave alternans (MTWA) and others. RESULTS: The median follow-up was 7·5 years. Resuscitated cardiac arrest and arrhythmic death due to ventricular arrhythmias ≥ 240/min was observed in 18% and 15% of patients, respectively. Cardiac death was observed in 28% of patients. The incidence of arrhythmic death and resuscitated cardiac arrest was identical in patients with ischemic heart disease with LVEF < 30% and ≥ 30%. No significant difference between subgroups with LVEF of < 30%, 30-39% and ≥ 40% was found either. MTWA, BRS, SDNN and LF to HF ratio failed to identify patients at risk of arrhythmic death in a multiple regression model. CONCLUSIONS: Ischemic heart disease patients with LVEF < 30% and ≥ 30% face the same risk of arrhythmic death. Stratification techniques fail to identify high-risk patients. Therefore, the current practice to constrain prophylactic ICDs to patients with severely reduced LVEF seems to be insufficient.

One-second MRI of a three-dimensional vocal tract to measure dynamic articulator modifications.

PURPOSE: To enable three-dimensional (3D) vocal tract imaging of dynamic singing or speech tasks at voxel sizes of 1.6 × 1.6 × 1.3 mm3 at 1.3 s per image. MATERIALS AND METHODS: A Stack-of-Stars method was implemented and enhanced to allow for fast and efficient k-space sampling of the box-shaped vocal tract using a 3 Tesla MRI system. Images were reconstructed using an off-line image reconstruction using compressed sensing theory, leading to the abovementioned spatial and temporal resolutions. To validate spatial resolution, a phantom with holes of defined sizes was measured. The applicability of the imaging method was validated in an eight-subject study of amateur singers that were required to sustain phonation at a constant pitch, past their comfortable expiratory level. A segmentation of the vocal tract over all phonation time steps was done for one subject. Anatomical distances (larynx position and pharynx width) were calculated and compared for all subjects. RESULTS: Analysis of the phantom study revealed that the imaging method could provide at least 1.6 mm isotropic resolution. Visual inspection of the segmented vocal tract during phonation showed modifications of the lips, tongue, and larynx position in all three dimensions. The mean larynx position per subject amounted to 52-85 mm, deviating up to 5% over phonation time. Parameter pharynx width was 32-181 mm2 on average per subject, deviating up to 16% over phonation time. Visual inspection of the parameter course revealed no common compensation strategy for long sustained phonation. CONCLUSION: The results of both phantom and in vivo measurements show the applicability of the fast 3D imaging method for voice research and indicate that modifications in all three dimensions can be observed and quantified. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:94-101.

The use of narrow band imaging for the detection of benign lesions of the larynx.

In the cases of uncertainty, even if the patient has no complaints about his voice quality, sometimes, benign vocal fold mass lesions are removed to exclude malignancy with the risk of resultant dysphonia. Narrow Band Imaging (NBI) enables a specific visualization of vessel structures in the superficial tissue. Benign lesions of the larynx are frequently characterized by abnormal vessel configuration or an absence of vessels in the area of the lesion. It was hypothesized that, in the primary diagnosis of patients with these benign lesions, the combination of white light and NBI endoscopy enables a better detection compared with white light endoscopy alone. Twenty-nine patients (eight patients with a cyst on a vocal fold, eight with a polyp, seven with a Reinke´s edema, two with a leukoplakia, one with a carcinoma, one with a granuloma, and two without any pathologic finding) were examined with normal white light and NBI endoscopy. 87 video sequences (29 white, 29 NBI, and 29 white/NBI) were generated and randomized and presented to 20 otolaryngologists who rated the videos in terms of the suspected diagnosis. Results were compared with the histopathologic findings of microlaryngoscopy. The probability of detecting benign lesions of the vocal folds was higher using NBI in combination with white light endoscopy compared with white light endoscopy alone. For vocal fold cysts, this difference was statistically significant. NBI endoscopy in combination with normal white light endoscopy improves the detection rate of benign lesions of the larynx, especially of vocal fold cysts.

Ensuring safety and functionality of electroglottography measurements during dynamic pulmonary MRI.

PURPOSE: To combine vocal tract measurements with dynamic MRI of the lungs to provide fundamental insights into the lung physiology during singing. METHODS: To analyze vocal fold oscillatory patterns during dynamic lung MRI, an electroglottography (EGG) system was modified to allow for simultaneous EGG measurements during MR image acquisitions. A low-pass filter was introduced to suppress residual radiofrequency (RF) coupling into the EGG signal. RF heating was tested in a gel phantom to ensure MR safety, and functionality of the EGG device was assessed in a volunteer experiment at singing frequencies from A5 to A3. In the recorded EGG signals, remaining RF interferences were removed by independent component analysis post processing, and standard EGG parameters such as fundamental frequency, contact quotient and jitter were calculated. In a second volunteer experiment, EGG recordings were compared with lung diameter measurements from 2D time-resolved trueFISP acquisitions. RESULTS: RF heating measurements resulted in less than 1.2°C temperature increase in the gel phantom. EGG parameters measured during MR imaging are within the range of ideal values. In the lung measurement, both the lung diameter and the EGG recordings could be successfully performed with only minimal interference. CONCLUSION: EGG recording is pos sible during dynamic lung MRI, and glottal activity can be studied safely at 1.5T. Magn Reson Med 76:1629-1635, 2016. © 2015 International Society for Magnetic Resonance in Medicine.

Acceleration of MRI of the vocal tract provides additional insight into articulator modifications.

PURPOSE: To accelerate dynamic imaging of the vocal tract during articulation. MATERIALS AND METHODS: Five subjects were imaged by magnetic resonance imaging (MRI) while repeating the word "Partikel" at 90 beats per minute, using both a radio-frequency-spoiled radial gradient echo sequence with golden angle projection rotation and a previously applied real-time Cartesian sequence. The acquired data were reconstructed using a CG-SENSE method and Cartesian reconstruction. The images from both methods were compared by measuring distances between anatomical landmarks that are important for resonance behavior of the vocal tract. Only commonly available hardware and software were used. RESULTS: With the presented radial method a spatial resolution of 1.8 mm at 25 frames per second could be achieved. Overall, the morphometric measurements of the vocal tract showed less deviation for the radial sequence both across repetitions and for all subjects. Fast modifications, such as complete lip closing, could be analyzed with greater fidelity using the high temporal resolution of the radial sequence. CONCLUSION: The results indicate that higher temporal resolution is a necessity to catch fast morphometric changes in the vocal tract.

A Comparison of Different Methods to Generate Tooth Surface Models Without Applying Ionizing Radiation for Digital 3-Dimensional Image Fusion With Magnetic Resonance Imaging-Based Data of the Head and Neck Region.

OBJECTIVE: The 3-dimensional display of the vocal tract and teeth is necessary in numerous clinical and scientific contexts. Due to the different tissue properties this can only be achieved by combining different imaging techniques. A comparison of methods to record the tooth surface to create combined models of the vocal tract and teeth without applying ionizing radiation is displayed in this study. METHODS: Four methods to record the tooth surface were compared concerning their clinical accuracy after combination with magnetic resonance imaging (MRI)-based vocal tract models. With 2 of the presented methods the information of the tooth surface was obtained from MRI data. With the other 2 methods, the tooth surface was captured using a digital and a conventional impression technique. RESULTS: Impression techniques received the best rating results. CONCLUSIONS: The digital 3-dimensional image fusion of dental impression and MRI resulted in a virtual model of the vocal tract and teeth with a high clinical accuracy without applying ionizing radiation.