Three-dimensional force analysis of surgical manipulations at the long process of the incus.

PURPOSE: Surgical manipulation with application of inappropriate force may damage middle ear structures leading to hearing loss. This work analyzes the forces applied in simulated otosurgical exercises in a laboratory set-up by measuring the spatial components of applied forces with objective assessment criteria. With these criteria, the individual force characteristics applied by the surgeon can be quantified and an objective feedback can be given about their surgical maneuvers. METHODS: A natural size model of the human incus was mounted on a load cell to measure the spatial forces in all three directions during different manipulation tasks performed under the microscope by ten surgeons from our department having different levels of experience in otosurgery. The motions of the incus model and the instrument tip were recorded simultaneously with a video camera. RESULTS: Independent of surgical experience, a three-dimensional force pattern could be detected with components transverse to the desired force directions. The measured forces applied by trainees showed larger variations in magnitude, in spatial distribution and in temporal course than those applied by experienced surgeons. A better repeatability of identical tasks, constancy of force patterns and low peak force values could be seen in the group of experienced surgeons. CONCLUSIONS: The laboratory system presented in this study using simultaneous video and 3-D force registration allows the objective assessment of surgical manipulations, e.g., at the long process of the incus. Training with video and force feedback provides information about surgical techniques and skill development of surgeons and has the potential to shorten the learning curve and to diminish intra-operative risks to patients.

Multicenter Clinical Trial of Vibroplasty Couplers to Treat Mixed/Conductive Hearing Loss: First Results.

OBJECTIVE: To evaluate the safety and effectiveness of round window (RW), oval window (OW), CliP and Bell couplers for use with an active middle ear implant. METHODS: This is a multicenter, long-term, prospective trial with consecutive enrollment, involving 6 university hospitals in Germany. Bone conduction, air conduction, implant-aided warble-tone thresholds and Freiburger monosyllable word recognition scores were compared with unaided preimplantation results in 28 moderate-to-profound hearing-impaired patients after 12 months of follow-up. All patients had previously undergone failed reconstruction surgeries (up to 5 or more). In a subset of patients, additional speech tests at 12 months postoperatively were used to compare the aided with the unaided condition after implantation with the processor switched off. An established quality-of-life questionnaire for hearing aids was used to determine patient satisfaction. RESULTS: Postoperative bone conduction remained stable. Mean functional gain for all couplers was 37 dB HL (RW = 42 dB, OW = 35 dB, Bell = 38 dB, CliP = 27 dB). The mean postoperative Freiburger monosyllable score was 71% at 65 dB SPL. The postimplantation mean SRT50 (speech reception in quiet for 50% understanding of words in sentences) improved on average by 23 dB over unaided testing and signal-to-noise ratios also improved in all patients. The International Outcome Inventory for Hearing Aids (IOI-HA)quality-of-life questionnaire was scored very positively by all patients. CONCLUSION: A significant improvement was seen with all couplers, and patients were satisfied with the device at 12 months postoperatively. These results demonstrate that an active implant is an advantage in achieving good hearing benefit in patients with prior failed reconstruction surgery.

On the origin of ear clicks during deglutition or pressure equalization.

To explore the origin of clicking sounds in the ear during deglutition or other pharyngeal movements, which are interpreted differently in the literature. Experimental study at a tertiary referral centre. Acoustic phenomena during a forced opening test of the Eustachian tube (ET) were studied in a temporal bone model. Additionally, in vivo experiments were carried out in healthy volunteers for ruling out movements of the ossicular chain or the drumhead as potential causes of clicks. Thus, acoustic recordings were performed parallel to stapedius or tensor reflex measurements or pneumatic video endoscopies of the tympanic membrane. Obviously the acoustic signals (clicks) appear when the tube opens, which could be visualized and acoustically recorded during forced opening tests in temporal bone experiments. Middle ear muscle contractions with movements of the tympanic membrane did not cause any click events. Together with the results of a previous paper (9) we interpret the clicks as disruptions of fluid or mucus films covering the mucosa during the ET opening. The final goal of our studies is to use such clicks as indicators of ET openings in a new tube function test, which has to be elaborated.

Intubating conditions and side effects of propofol, remifentanil and sevoflurane compared with propofol, remifentanil and rocuronium: a randomised, prospective, clinical trial.

BACKGROUND: Tracheal intubation without muscle relaxants is usually performed with remifentanil and propofol or sevoflurane. Remifentanil 1.0 to 4.0 µg·kg(-1) and propofol 2.0-3.0 mg·kg(-1) or sevoflurane up to 8.0 Vol% provide acceptable, i.e. excellent or good intubating conditions. We hypothesized that sevoflurane 1.0 MAC would provide acceptable intubating conditions when combined with propofol and remifentanil. METHODS: Eighty-three patients to be intubated were randomised to two groups. The SEVO group received propofol 1.5 mg kg(-1), remifentanil 0.30 µg kg min(-1) and sevoflurane 1.0 MAC; the MR group received the same doses of propofol and remifentanil plus rocuronium 0.45 mg kg(-1). We evaluated intubation and extubation conditions, mean arterial pressure (MAP), heart rate (HR) and bispectral index (BIS). The vocal cords were examined for injury by videolaryngoscopy before and 24 hours after surgery. RESULTS: ACCEPTABLE INTUBATING CONDITIONS WERE SEEN MORE FREQUENTLY WITH ROCURONIUM THAN WITH SEVOFLURANE: 97% versus 82%; p = 0.03; the subscore for vocal cords was comparable: 100% versus 98%. MAP before intubation decreased significantly compared with the MAP at baseline to the same extent in both groups; ephedrine IV was given in 15 (SEVO) versus 16 (MR) patients; p = 0.93. BIS at tracheal intubation was 27 (13-65) in the SEVO group, 29 (14-62) in the MR group; p = 0.07. Vocal cord injuries (oedema, haematoma) were similar: 4 patients in each group. CONCLUSIONS: Overall intubating conditions were better when rocuronium was used; the subscore for vocal cords was comparable. The incidence of side effects was the same in the two groups. TRIAL REGISTRATION: ClinicalTrials.Gov: NCT 01591031.

Would an endosteal CI-electrode make sense? Comparison of the auditory nerve excitability from different stimulation sites using ESRT measurements and mathematical models.

UNLABELLED: Regarding potential endosteal cochlear implant electrodes, the primary goal of this paper is to compare different intra- and extra-cochlear stimulation sites in terms of current strengths needed for stimulating the auditory nerve. Our study was performed during routine cochlear implantation using needle electrodes for electric stimulation and by visually recording electrically elicited stapedius reflexes (ESRT) as a measure for the stimulus transfer. Of course this rather simple setup only allows rough estimations, which, however, may provide further arguments whether or not to proceed with the concept of an endosteal electrode. In addition, a mathematical model is being developed. In a pilot study, intra-operative electric stimuli were applied via a needle electrode commonly used for the promontory stimulation test. Thus, stapedius reflex thresholds (ESRTs), electrically elicited via the needle from different points inside and outside the cochlea served as indicators for the suitability of different electrode positions towards the modiolus. Tests were performed on 11 CI-recipients. In addition, the extension of electrical fields from different stimulation sites is simulated in a mathematical cochlea model. In most patients ESRT measurements could be performed and evaluated. Thus an "endosteal" stimulation seems possible, although the current intensities must be higher than at intraluminal stimulation sites. Moreover, our model calculations confirm that the extension of electric fields is less favourable with increasing distance from the electrode to the ganglion nerve cells. In terms of hearing, the concept of an endosteal electrode should only be promoted, if its superiority for hearing preservation can be proven, e.g. in animal experiments. However, for other indications like the electric suppression of tinnitus, further research seems advisable. LEVELS OF EVIDENCE: N/A.

Polydimethylsiloxane for injection laryngoplasty: two cases necessitating tracheotomy.

The surgical treatment of glottic insufficiency due to lesions of the recurrent laryngeal nerve has become a routine procedure in the last few decades. In particular, injection laryngoplasty with polydimethylsiloxane (PDMS) has proved to be an easy, effective and safe method for vocal fold medialization. It is a biologically inert substance having almost ideal properties as a filler; complications related to its intralaryngeal use such as migration, or granuloma formation are extremely rare and allergic reactions have not been reported as yet. We discuss two cases representing the first description of acute severe complications after injection laryngoplasty with PDMS.

Laryngeal injuries following endotracheal intubation in ENT surgery: predictive value of anatomical scores.

Endotracheal intubation has been associated with a threefold higher incidence of laryngopharyngeal complaints following anesthesia in comparison to laryngeal mask airway. Such complaints, including hoarseness and sore throat, have been reported in up to 90% of patients within 24 h of extubation. The purpose of this study was to determine which preoperatively documented clinical and anatomic parameters are predictive of laryngo-pharyngeal trauma resulting from elective endotracheal intubation. Fifty-three patients undergoing ENT procedures requiring general anesthesia with endotracheal intubation were recruited. Pre and postoperative laryngostroboscopic examination was performed and findings correlated to preoperative clinical and anatomic parameters. Readily assessed anatomic parameters including height (>180 cm) and weight (>80 kg) correlated significantly to the Eckerbom grade of intubation-associated acute laryngeal injury (rs = 0.374; p = 0.006 and rs = 0.278; p = 0.044, respectively). The mandibular protrusion test also correlated significantly to the Eckerbom grade (rs = 0.462, p = 0.001) while the upper-lip-bite test showed significant correlation to impaired vocal fold oscillation (rs = 0.288, p = 0.036), with injury prediction sensitivities of 37.5 and 39.4%, respectively. No parameters correlated to subjective complaints (n = 5, 9.2%). This study provides suggestions on how to improve the classification of intubation-associated laryngeal injuries as well as providing the basis for larger clinical trials in other surgical subspecialties.

Development of a specially tailored local drug delivery system for the prevention of fibrosis after insertion of cochlear implants into the inner ear.

A cochlear implant (CI)-associated local drug delivery system based on dexamethasone (DMS) was developed with the purpose to inhibit the growth of fibrotic tissue which influences the signal transmission from the CI to the neurons of the inner ear. For the realization of a targeted DMS delivery the following concepts were combined: modification of the silicone-based electrode carrier by incorporation of DMS and a DMS-containing polymeric coating chemically attached on the surface of the electrode carrier. It was demonstrated that the coated CI showed a high coating stability in a simulated implantation procedure. The in vitro drug release studies in a quasi-stationary model revealed a faster DMS release in the initial phase originating from the DMS-containing coatings and then a lower and sustained DMS release originating from the DMS-loaded silicone carrier. The performed in vitro biocompatibility study confirmed that the released DMS was non-toxic for cultured spiral ganglion cells.

[Optical coherence tomography in otolaryngology]. / Az optikai koherenciatomográfia alkalmazási lehetoségei a fül-orr-gégészetben.

Optical coherence tomography is an imaging technique based on coherence interferometry. It is used in many medical fields due to its non-invasive imaging capabilities with micrometer resolution. The aim of the authors was to review the applicability of the optical coherence tomography in otolaryngology. Literature data and their own studies show that optical coherence tomography is a reliable method for identifying and targeted biopsy of inflammated, pre-malignant or cancer tissue in human laryngeal and pharyngeal mucosa. Another emerging field for optical coherence tomography is diagnosis of middle ear diseases, especially stapes ankylosis and cholesteatoma.

Rigid confocal endoscopy for in vivo imaging of experimental oral squamous intra-epithelial lesions.

BACKGROUND: A rigid confocal endoscope has been developed to assess the oral squamous epithelium of mice and to determine sensitivity, specificity, and accuracy of this new technology. METHODS: This endoscope is connected to the commercially available Heidelberg Retina Tomograph (HRT). HRT is a device with a 670-nm diode laser designed to acquire topographical measurements of the optic nerve head. Real-time rigid confocal endoscopy is demonstrated by imaging the epithelial lesions of a mice model. Six-week-old male C57Bl/6 mice were randomly divided into a non-treated group (n = 10) and into a 4-nitroquinoline 1-oxide (4-NQO)-treated group (n = 50). In the 4-NQO-treated group, the mice obtained 4-nitroquinoline 1-oxide in the drinking water (100 microg/ml) to induce tumourigenesis in the mouse tongue. The 4-NQO-solution was diluted in the drinking water for mice. After an 8-16-week carcinogen treatment with 4-NQO (ad libitum), mouse tongues were dissected within 3 h after CO(2) overdose. After confocal microscopy of all lesions of the tongue, conventional histopathological investigation was performed. RESULTS: The inter-rater reliability for the two observers of the confocal microscopic findings was found to be Kappa = 0.59 (P < 0.001). The penetration depth varied in the healthy tissue of the underside of the tongue throughout this study and was measured between 104 and 240 microm. In keratotic lesions, the penetration depths were diminished and varied between 80 and 140 microm. Strong keratinization inhibits the evaluation of the epithelium. For differentiation between low-grade and high-grade squamous intra-epithelial lesions, a sensitivity and specificity of 73% and 88% was reached. CONCLUSIONS: The animal experiment with this non-invasive new technology indicates that this imaging technology facilitates the detection of pre-cancerous lesions of the underside of the oropharynx. Human studies on oropharyngeal and laryngeal lesions are needed to prove the applicability of this method in the field of otorhinolaryngology.

Normative data for a solution-based taste test.

The aim of our study was to study gustatory function in a large portion of the general population using liquid tastants, extending previous research. Further, we investigated the test-retest reliability of the test used. Data from 944 healthy subjects were used (498 women and 446 men, mean age 45 years; age range 5-90 years). For lateralized assessment of gustatory function, liquid taste solutions were used with different concentrations of each tastant (sweet 0.03, 0.1, 0.4, 2 g/mL sucrose solution; sour 0.01, 0.05, 0.1, 0.15 mL citric acid; salty 0.025, 0.075, 0.15, 0.36 mL sodium chloride solution; bitter 0.0002, 0.0005, 0.001, 0.01 mL quinine hydrochloride). A drop (approximately 20 µL) of liquid tastant was applied on the right side or on the left side of the anterior/posterior third of the extended tongue. The taste test had a good test-retest reliability r (304) = 0.78 (P < 0.001) for the total score and r (304) = 0.77 (P < 0.001) for the right-sided measures and r (304) = 0.75 (P < 0.001) for the left-sided measures, respectively. Gustatory sensitivity was found to decrease with age; women were more sensitive to gustatory stimuli than men. Irrespective of the sex-related differences, the total score at the 10th percentile was 28 in subjects younger than 15 years, 26.1 for ages from 16 to 35 years, 25 for ages from 36 to 55 years, and 24 for subjects older than 56 years of age. In conclusion, this test is recommended for clinical assessment of the ability to taste. The test provides reliable data, which is easy to handle, inexpensive, timesaving and can be self-made.

Clinical Impact of Rare and Compound Mutations of Epidermal Growth Factor Receptor in Patients With Non-Small-Cell Lung Cancer.

BACKGROUND: Standard therapy of advanced non-small-cell lung cancer harboring an activating mutation in the epidermal growth factor receptor (EGFR) gene is treatment with tyrosine kinase inhibitors (TKI). However, for rare and compound mutations of the EGFR gene, the clinical evidence of TKI therapy is still unclear. PATIENTS AND METHODS: A total of 2906 lung cancer samples were analyzed for EGFR mutations during routine analysis between 2010 and 2017. The samples have been investigated by Sanger sequencing and since 2014 by next-generation sequencing. RESULTS: We detected EGFR mutations in 408 specimens (14%). Among these, we found 41 samples with rare and 22 with compound mutations. In these 63 samples, 56 different rare EGFR mutations occurred. Information about the clinical outcome was available for 37. Among those with rare mutations, only one patient harboring the mutation p.G874D had disease that responded to first-generation TKI therapy. In contrast, the disease of all patients with compound mutations responded to first- or second-generation TKI therapy. Furthermore, we collected data on clinical relevance regarding TKI therapy from different databases and from an additional literature search, and only found data for 36 of the 56 detected rare mutations. CONCLUSION: Information about the clinical outcome of patients with rare and compound EGFR mutations remains limited. At present, second- and third-generation TKIs are available, which may represent new treatment strategies for these patients. Therefore, it is becoming increasingly important to maintain databases concerning rare EGFR mutations.

Transient facial palsy in two cases of benign, very rare middle ear tumors (carcinoid tumor and myxoma).

OBJECTIVE: Presentation of the clinical features of 2 very rare middle ear tumors in which the guiding symptom was facial palsy. MATERIAL AND METHODS: Illustrative case reports about a myxoma and a carcinoid tumor of the middle ear associated with peripheral facial palsy. RESULTS: The facial palsy was transient in either case, and its pathomechanism is open for discussion. In both cases, the initial symptoms were typical for an inflammatory process. Moreover, both tumor entities are typically found in organs other than the ear; if located in the middle ear, those neoplasms grow rather superficially. In those cases, a surgical exposure of the middle ear is indicated. CONCLUSION: The etiopathology of an acute peripheral facial palsy is often hard to identify. If the facial weakness starts together with symptoms suggesting an inflammatory process, the differential diagnosis may be focused first on diseases like herpes zoster oticus and a severe course of acute purulent otitis media. We report the cases of 2 rare middle ear tumors causing facial palsy. Treatment of choice should be complete surgical excision.

Monitoring residual hearing during cochlear implantation by intra-operative brainstem audiometry.

OBJECTIVE: Aim of this paper is to prove the applicability of intra-operative recordings of auditory brainstem responses during cochlear implantation. METHODS: The clinical practicability of intra-operative monitoring of hearing thresholds (Notched-Noise BERA, Amplitude Modulation Following Response [AMFR]) is presented in the respective case. The recordings were performed prior to the cochlear implantation and were compared with those obtained during and after cochlear implantation. RESULTS: It is demonstrated that the patient's cochlear function can be monitored; residual hearing is available after surgery. CONCLUSION: The possibility of monitoring of hearing thresholds may add some security to the concept of electric-acoustic stimulation.

Effect of Tissue Heterogeneity on the Transmembrane Potential of Type-1 Spiral Ganglion Neurons: A Simulation Study.

Electric stimulation of the auditory nerve by cochlear implants has been a successful clinical intervention to treat the sensory neural deafness. In this pathological condition of the cochlea, type-1 spiral ganglion neurons in Rosenthal's canal play a vital role in the action potential initiation. Various morphological studies of the human temporal bones suggest that the spiral ganglion neurons are surrounded by heterogeneous structures formed by a variety of cells and tissues. However, the existing simulation models have not considered the tissue heterogeneity in the Rosenthal's canal while studying the electric field interaction with spiral ganglion neurons. Unlike the existing models, we have implemented the tissue heterogeneity in the Rosenthal's canal using a computationally inexpensive image based method in a two-dimensional finite element model. Our simulation results suggest that the spatial heterogeneity of surrounding tissues influences the electric field distribution in the Rosenthal's canal, and thereby alters the transmembrane potential of the spiral ganglion neurons. In addition to the academic interest, these results are especially useful to understand how the latest tissue regeneration methods such as gene therapy and drug-induced resprouting of peripheral axons, which probably modify the density of the tissues in the Rosenthal's canal, affect the cochlear implant functionality.

Noise exposure of the inner ear during drilling a cochleostomy for cochlear implantation.

OBJECTIVES: Inserting an electrode array into the cochlea may cause inner ear trauma, which has to be minimized, particularly in cochlear implant patients with substantial residual hearing. Another potential inner ear trauma has, to a large extent, been neglected so far: the acoustic trauma that can occur during cochleostomy using different techniques. In this study, the noise exposure of the inner ear during the drilling procedure was re-evaluated. In experiments on temporal bones, quantitative measurements of sound pressure level (SPL) were carried out while a cochleostomy for cochlear implantation was drilled. STUDY DESIGN: Experimental study. MATERIALS AND METHODS: Acoustic measurements during different drilling procedures were carried out on four human temporal bone preparations equipped with microphones attached to the round window. Special calibrations were carried out, which allowed determination of SPLs affecting the cochlea during the drilling procedure. RESULTS: The highest SPLs measured on the cochlea were recorded when a still-intact endosteal membrane was touched by the burr. The SPL exceeded 130 dB and reached a level almost comparable with the situation when the ossicular chain is touched by a running burr. CONCLUSIONS: In the drilling procedure for a cochleostomy, the inner ear may be affected by very high SPLs, particularly if the endosteal membrane is left intact and comes into contact with the running burr. Of course, the resulting SPLs depend on the drilling speed and the size and characteristics of the burr (larger burrs cause higher SPLs); however, we are of the opinion that the cochlear function is at risk, anyway, if special precaution is not exercised. Even when working with reduced drilling speed, the surgeon should be aware of the high risk in the form of an acoustic trauma, which may endanger residual hearing. Recommendations in terms of "soft surgery" are given in the paper (e.g., the use of microhooks instead of a drill to remove the very last shell of bone covering the cochlea).

Optical coherence tomography as an orientation guide in cochlear implant surgery?

CONCLUSION: With optical coherence tomography (OCT) it is basically possible to reveal parts of the cochlear morphology without opening its enveloping membranes. Thus, it may serve as a helpful guide for the surgeon to localize the scala tympani precisely before opening the fluid-filled inner ear to insert the electrode array. OBJECTIVE: To improve anatomical orientation in cochlear implant surgery before definitively opening the fluid-filled inner ear. The question was whether a new imaging technique, OCT, might provide information about the site of the underlying inner ear structures (scala tympani, scala vestibuli) and could, consequently, guide the surgeon towards the scala tympani. MATERIALS AND METHODS: In a preliminary study, OCT was carried out on human temporal bone preparations, in which a cochleostomy ('fenestration') was performed leaving the endosteum and the fluid-filled inner ear intact. OCT was applied via a prototype of a specially equipped operating microscope. The mode of OCT used in this context was spectral-domain (SD)-OCT. RESULTS: On scans, which can be read analogous to B-mode sonography, OCT provides information about structures on the inner surface of the partly exposed but still intact membranous cochlear lining - such as scala tympani or scala vestibuli.

Contact endoscopic comparison of morphology of human fungiform papillae of healthy subjects and patients with transected chorda tympani nerve.

BACKGROUND: The chorda tympani nerve (CTN) carries gustatory fibers from taste buds of fungiform papillae (fPap) of the anterior portion of the tongue. Accordingly, middle ear surgery with transection of the CTN may result in gustatory impairment. With use of contact endoscopy, the present study aimed to compare number and shape of fPap and subepithelial vessel formation in patients after CTN transection with that of healthy controls. MATERIAL AND METHODS: The number of fPap per square centimeter was obtained in addition to measures of gustatory sensitivity using electrogustometry and intensity ratings of natural taste stimuli. Data from 32 healthy subjects (mean age 40 yr; 16 female, 16 male) were compared with those from 14 patients whose CTN had been cut and partly resected during middle ear surgery because of cholesteatoma (mean age 38 yr; 7 female, 7 male). Middle ear surgery was performed by two of the authors. RESULTS: In healthy subjects, a higher fPap density was found on the tongue's tip compared with its edge; younger subjects had higher densities than older subjects. No sex-related differences were observed. Patients with transected CTN exhibited a significant decrease of taste function as measured with both natural and electric stimuli. In patients, we found significantly fewer and flatter fPap on the side of the tongue where surgery had been performed in comparison with the contralateral side. In addition, fPap density at the ipsilateral side was significantly lower compared with fPap density on the respective side in healthy controls. CONCLUSION: As established through contact endoscopy, the number of fPap decreases in relation to deafferentation and also in relation to the subjects' age, both of which are accompanied by a decreased gustatory sensitivity.

Laser scanning microscopy of the human larynx mucosa: a preliminary, ex vivo study.

OBJECTIVE: Laser scanning microscopy (LSM) supplies in vivo information from epithelia up to depths between 0.1 to 0.5 mm. The aim of this ex vivo prospective pilot study was to investigate the potential use of LSM for the diagnosis of laryngeal cancer and its precursors. METHODS: Forty-three larynx specimens of 26 patients (age 35-61 years, mean age 51.9+/-9.5 years; 7 women and 19 men) with laryngeal lesions were investigated with LSM. The LSM findings were compared with histopathologic sections. The following criteria were used for characterization of cancerous lesions: enlarged nuclei, enlarged cells with variable shapes, cluster of cells, increased nucleus/cytoplasm ratio, irregular cell architecture, and loss of cellular junctions characterized by lack of visualization of the cell membrane. RESULTS: LSM enables the visualization of epithelium up to the basement membrane, Reincke space, the subepithelial vessels, and the fibers of the subepithelial space. In contrast to the squamous epithelium, the respiratory epithelium bears kinocilia. The beat of the cilia and the directed mucous transport can be observed ex vivo. With the use of the presented malignancy criteria, a sensitivity of 72.7% and a specificity of 82.9% for differentiation of dysplasia and benign laryngeal lesions from cancer were reached. CONCLUSIONS: LSM in an ex vivo manner supplies microscopic images up to the subepithelial space. LSM could represent a new technology in laryngology to visualize larynx epithelia. In the next step, in vivo LSM will be applied to evaluate laryngeal lesion in vivo.