Voice outcome in medialisation thyroplasty with and without arytenoid adduction: a prospective comparison using intraoperative voice measurements.

PURPOSE: Arytenoid adduction as an addition to medialisation thyroplasty is highly advocated by some surgeons in selected cases but deemed less necessary by others in patients with unilateral vocal fold paralysis. This study aims to evaluate the additional benefits on voice outcome of arytenoid adduction in patients with unilateral vocal fold paralysis undergoing medialisation thyroplasty using intra-operative voice measurements. DESIGN/METHODS: A prospective study was conducted. Voice audio recordings were obtained at 4 moments; 1. direct prior to the start of surgery, 2. during surgery after medialisation thyroplasty, 3. during surgery after medialisation and arytenoid adduction, 3 months postoperative. At these same timepoints patients rated their own voice on a numeric rating scale between 0 and 10. The blinded recordings were rated by consensus in a team of experienced listeners, using the Grade of the GRBAS scale. Furthermore, the Voice Handicap Index was administered before and at 3 months after surgery. RESULTS: Ten patients who underwent medialisation and arytenoid adduction at our tertiary referral hospital between 2021 and 2022, were included. One patient was excluded after surgery. The intraoperative measurements showed a Grade score of 1.4 preoperatively, improving to 1.2 after medialisation, 1.2 after medialisation and arytenoid adduction, and further improving to 0.4 at 3 months postoperative, which was a not statistically significant improvement (p = 0.2). The intraoperative subjective numeric rating scale showed a statistically significant improvement from 3.9 preoperatively, to 6.1 after medialisation, 7.1 after medialisation and arytenoid adduction and a 7.6 at 3 months postoperative (p = 0.001). The Voice Handicap Index total score showed a statistically significant improvement from 71 points before surgery to 13 at 3 months after surgery (p = 0.008). CONCLUSIONS: Our study using intraoperative voice measurements indicate that the addition of arytenoid adduction to medialisation thyroplasty is a benefit in selected patients although more studies are needed due to the many limitations inherent to this field of investigation.

Long-term functional outcomes in tumour stage T2 glottic carcinoma after radiotherapy.

OBJECTIVE: To evaluate the long-term functional outcomes in patients who received primary radiotherapy for tumour-node stage T2N0 glottic carcinoma, stratified for tumour extension. METHODS: A cross-sectional study was performed on patients who were treated with radiotherapy for T2N0 glottic carcinoma. Four questionnaires were used to measure different aspects of functional outcome. In addition, objective evaluation and perceptual analysis were performed. RESULTS: Fourteen patients were included in this study. The median time between the start of radiotherapy and assessment was 42 months (range, 26-143 months). Patients reported high-level functioning, with low symptom scores and good swallowing function, and showed a median dysphonia grade of 1.5. The median Voice Handicap Index-30 score was 17.5. CONCLUSION: Patients with T2N0 glottic carcinoma treated with radiotherapy had good long-term quality of life, with low symptom scores, good swallowing functioning and slightly elevated voice outcome parameters.

Union of the European Phoniatricians' position statement on the exit strategy of phoniatric and laryngological services: staying safe and getting back to normal after the peak of coronavirus disease 2019 (issued on 25th May 2020).

BACKGROUND: The following position statement from the Union of the European Phoniatricians, updated on 25th May 2020 (superseding the previous statement issued on 21st April 2020), contains a series of recommendations for phoniatricians and ENT surgeons who provide and/or run voice, swallowing, speech and language, or paediatric audiology services. OBJECTIVES: This material specifically aims to inform clinical practices in countries where clinics and operating theatres are reopening for elective work. It endeavours to present a current European view in relation to common procedures, many of which fall under the aegis of aerosol generating procedures. CONCLUSION: As evidence continues to build, some of the recommended practices will undoubtedly evolve, but it is hoped that the updated position statement will offer clinicians precepts on safe clinical practice.

Six years of progress in the oral biopharmaceutics area - A summary from the IMI OrBiTo project.

OrBiTo was a precompetitive collaboration focused on the development of the next generation of Oral Biopharmaceutics Tools. The consortium included world leading scientists from nine universities, one regulatory agency, one non-profit research organisation, three small/medium sized specialist technology companies together with thirteen pharmaceutical companies. The goal of the OrBiTo project was to deliver a framework for rational application of predictive biopharmaceutics tools for oral drug delivery. This goal was achieved through novel prospective investigations to define new methodologies or refinement of existing tools. Extensive validation has been performed of novel and existing biopharmaceutics tools using historical datasets supplied by industry partners as well as laboratory ring studies. A combination of high quality in vitro and in vivo characterizations of active drugs and formulations have been integrated into physiologically based in silico biopharmaceutics models capturing the full complexity of gastrointestinal drug absorption and some of the best practices has been highlighted. This approach has given an unparalleled opportunity to deliver transformational change in European industrial research and development towards model based pharmaceutical product development in accordance with the vision of model-informed drug development.

Effects of absorption-modifying excipients on jejunal drug absorption in simulated fasted and fed luminal conditions.

Oral administration of drug products is the preferred administration route. In recent decades there has been an increase in drug candidates with low solubility and/or low permeability. To increase the possibility of oral administration for the poorly permeating drugs, the use of absorption modifying excipients (AMEs) has been proposed. These types of AMEs may also affect the regulatory assessment of a novel drug delivery system if they affect the absorption of a drug from any of the four BCS classes. The effects of AMEs have previously been investigated in various animal models, including the single-pass intestinal perfusion (SPIP) in rats. To further improve the biorelevance and the in vivo predictiveness of the SPIP model, four compounds (atenolol, enalaprilat, ketoprofen, metoprolol) were perfused in fasted or fed state simulated intestinal fluid (FaSSIF or FeSSIF) together with the AMEs N-acetyl-cysteine, caprate, or sodium dodecyl sulfate. For the highly soluble and poorly permeating compounds enalaprilat and atenolol (BCS class III), the flux was increased the most by the addition of SDS in both FaSSIF and FeSSIF. For ketoprofen (BCS class II), the flux decreased in the presence of all AMEs in at least one of the perfusion media. The flux of metoprolol (BCS class I) was not affected by any of the excipients in none of simulated prandial states. The changes in magnitude in the absorption of the compounds were in general smaller in FeSSIF than in FaSSIF. This may be explained by a reduced free concentration AMEs in FeSSIF. Further, the results in FeSSIF were similar to those from intrajejunal bolus administration in rat in a previous study. This suggests that the biorelevance of the SPIP method may be increased when investigating the effects of AMEs, by the addition of intraluminal constituents representative to fasted and/or fed state to the inlet perfusate.

Rat intestinal drug permeability: A status report and summary of repeated determinations.

Intestinal permeability is a key biopharmaceutical variable in pharmaceutical research and development, and regulatory assessment. In situ rat models are often used to predict the corresponding human intestinal permeability data. The rat single-pass intestinal perfusion (SPIP) and intestinal closed loop (ICL) models are commonly applied. The primary objective of this study was to collect, summarize, and evaluate all the available intestinal permeability data for drugs that have been obtained using these two in-situ rat models. The permeability data were also investigated for variability between the experimental designs. The literature survey found 635 permeability determinations for 90 drugs. The studies were performed on the jejunum (n = 284), whole small intestine (n = 111), colon (n = 108), ileum (n = 101), and duodenum (n = 30). All the SPIP (n = 484) and ICL (n = 147) permeability values were summarized in an easily accessible database. There was wide variability in the intestinal permeability to each drug between studies, which was unrelated to the permeability class of the drug. There was no relationship between rat intestinal permeability and luminal pH, luminal drug concentration, rat strain, experimental method, or intestinal region. There was, however, a correlation between permeability values determined in the same laboratory. This report showed that the SPIP and ICL methods are important in situ models for understanding and predicting intestinal drug absorption. However, conclusions based on permeability values sourced from different laboratories may not be reliable. Because each permeability study is unique and because between- and even within-laboratory variability can be substantial, data from individual studies should preferably be interpreted separately.

Evaluation of drug permeability calculation based on luminal disappearance and plasma appearance in the rat single-pass intestinal perfusion model.

The rat single-pass intestinal perfusion (SPIP) model is commonly used to investigate gastrointestinal physiology and membrane drug transport. The SPIP model can be used with the intestinal segment inside or outside the abdomen. The rats can also be treated with parecoxib, a selective cycloxygenase-2 inhibitor that has been shown to affect some intestinal functions following abdominal surgery, such as motility, epithelial permeability, fluid flux and ion transport. However, the impact of extra-abdominal placement of the intestinal segment in combination with parecoxib on intestinal drug transport has not been investigated. There is also uncertainty how well intestinal permeability determinations based on luminal drug disappearance and plasma appearance correlate in the rat SPIP model. The main objective of this rat in vivo study was to investigate the effect of intra- vs. extra-abdominal SPIP, with and without, pretreatment with parecoxib. The effect was evaluated by determining the difference in blood-to-lumen 51Cr-EDTA clearance, lumen-to-blood permeability of a cassette-dose of four model compounds (atenolol, enalaprilat, ketoprofen, and metoprolol), and water flux. The second objective was to compare the jejunal permeability values of the model drugs when determined based on luminal disappearance or plasma appearance. The study showed that the placement of the perfused jejunal segment, or the treatment with parecoxib, had minimal effects on membrane permeability and water flux. It was also shown that intestinal permeability of low permeability compounds should be determined on the basis of data from plasma appearance rather than luminal disappearance. If permeability is calculated on the basis of luminal disappearance, it should preferably include negative values to increase the accuracy in the determinations.

Voice outcome indicators for unilateral vocal fold paralysis surgery: A survey among surgeons.

INTRODUCTION: Standardization of voice outcomes indicators (VOIs) is an important issue when it comes to evaluating and comparing surgical treatments for Unilateral Vocal Fold Paralysis (UVFP). In a recent review, 11 VOIs were found to represent 80% of the VOIs cited in the literature. A survey was launched among the European laryngologists to acquire surgeons' opinions on the above mentioned preselected VOIs. MATERIAL AND METHOD: The electronic survey took place between November and December 2016. Three general questions were asked about surgeon's practice setting(s) and experience. The eleven next questions concerned (a) surgeon's VOIs preference and (b) their estimates of post-operative target values, they would consider being satisfactory. RESULTS: The response rate was 16% (50 surveys). The majority of responders worked in tertiary hospitals (50%), had 15 years of experience with UVFP and performed on average 20 UVFP related procedures a year. The VOIs that were favored by the responding surgeons were, in decreasing order of importance, Voice handicap Index (VHI-30), Maximum Phonation Time (MPT), GRBAS-I, Mean Airflow Rate (MeAF), Jitter and Shimmer. There was an excellent consensus on post-operative VOI target values between survey's results and the literature data, except for three VOIs that showed somewhat divergent tendencies (absolute VHI-30, Jitter and Shimmer). CONCLUSIONS: Three VOIs are favored by surgeons: VHI-30, MPT and GRBAS-I. Jitter and Shimmer, although very frequently reported and statistically valid in the literature, come last concerning surgeon's choice as VOI for UVFP treatment assessment.

Single bead investigation of a clinical drug delivery system - A novel release mechanism.

Microgels, such as polymeric hydrogels, are currently used as drug delivery devices (DDSs) for chemotherapeutics and/or unstable drugs. The clinical DDS DC bead® was studied with respect to loading and release, measured as relative bead-volume, of six amphiphilic molecules in a micropipette-assisted microscopy method. Theoretical models for loading and release was used to increase the mechanistic understanding of the DDS. It was shown that equilibrium loading was independent of amphiphile concentration. The loading model showed that the rate-determining step was diffusion of the molecule from the bulk to the bead surface ('film control'). Calculations with the developed and applied release model on the release kinetics were consistent with the observations, as the amphiphiles distribute unevenly in the bead. The rate determining step of the release was the diffusion of the amphiphile molecule through the developed amphiphile-free depletion layer. The release rate is determined by the diffusivity and the tendency for aggregation of the amphiphile where a weak tendency for aggregation (i.e. a large cacb) lead to faster release. Salt was necessary for the release to happen, but at physiological concentrations the entry of salt was not rate-determining. This study provides valuable insights into the loading to and release from the DDS. Also, a novel release mechanism of the clinically used DDS is suggested.

Mechanistic modelling of intestinal drug absorption - The in vivo effects of nanoparticles, hydrodynamics, and colloidal structures.

Particle size reduction is a traditional approach to increase the intestinal absorption of active pharmaceutical ingredients with poor intestinal solubility, by increasing the particle dissolution rate. However, an increase in the dissolution rate cannot always fully explain the effects of nanoformulations, and a method of assessing the potential benefits of a nanoformulation in vivo would hence be of great value in drug development. A novel mathematical model of a nanoformulation, including interlinked descriptions of the hydrodynamics, particle dissolution and diffusion of particles and colloidal structures (CS), was developed to predict the combined in vivo effects of these mechanisms on drug absorption. The model successfully described previously reported in vivo observations of nanoformulated aprepitant in rats, at various drug concentrations and in the presence or absence of CS. The increase in absorption rate was explained as a direct consequence of the increased drug concentration at the membrane, caused by the contributing effects of the diffusion of both nanoparticles and CS into which the drug had partitioned. Further simulations supported the conclusion that the model can be applied during drug development to provide a priori assessments of the potential benefits of nanoformulations.

Jejunal absorption of aprepitant from nanosuspensions: Role of particle size, prandial state and mucus layer.

The number of highly lipophilic active pharmaceutical ingredients (APIs) in pharmaceutical development has been constantly increasing over recent decades. These APIs often have inherent issues with solubility and dissolution, limiting their oral bioavailability. Traditionally, a reduction in particle size to the micrometer range has been used to improve dissolution. More recently, size reduction to the nanometer range has been introduced, which further increases the dissolution rate, but may also involve other mechanisms for increasing bioavailability. The effect of particle size on the absorption of aprepitant was investigated using the single-pass intestinal perfusion (SPIP) model in the rat jejunum. Phosphate buffer, fasted-state simulated intestinal fluid (FaSSIF), and fed-state simulated intestinal fluid (FeSSIF) were used as perfusion media to increase understanding of the processes involved and the effects of colloidal structures. The role of mucus on intestinal absorption was investigated by adding the mucolytic agent N-acetyl-cysteine (NAC). The absorption of aprepitant from the nanosuspensions was similar with all perfusion media (buffer = FaSSIF = FeSSIF), whereas food had a pronounced effect on absorption from the microsuspensions (FeSSIF > FaSSIF > buffer). The colloidal structures hence contributed to absorption from the microsuspensions. Partitioning of aprepitant from the nanosuspension into the colloidal structures decreased the amount of nanoparticles available, which offset the effect of food. The appearance flux of aprepitant in blood was non-significantly decreased for nanosuspensions of aprepitant with NAC versus without NAC in buffer (ratio of 2:1), indicating that particle deposition in the mucus may have been decreased as the layer thinned, with subsequently reduced intestinal absorption. The study also showed that the SPIP model is suitable for investigating detailed absorption mechanisms using complex perfusion media, which increase the biorelevance of the model.

Time-dependent effects on small intestinal transport by absorption-modifying excipients.

The relevance of the rat single-pass intestinal perfusion model for investigating in vivo time-dependent effects of absorption-modifying excipients (AMEs) is not fully established. Therefore, the dynamic effect and recovery of the intestinal mucosa was evaluated based on the lumen-to-blood flux (Jabs) of six model compounds, and the blood-to-lumen clearance of 51Cr-EDTA (CLCr), during and after 15- and 60-min mucosal exposure of the AMEs, sodium dodecyl sulfate (SDS) and chitosan, in separate experiments. The contribution of enteric neurons on the effect of SDS and chitosan was also evaluated by luminal coadministration of the nicotinic receptor antagonist, mecamylamine. The increases in Jabs and CLCr (maximum and total) during the perfusion experiments were dependent on exposure time (15 and 60 min), and the concentration of SDS, but not chitosan. The increases in Jabs and CLCr following the 15-min intestinal exposure of both SDS and chitosan were greater than those reported from an in vivo rat intraintestinal bolus model. However, the effect in the bolus model could be predicted from the increase of Jabs at the end of the 15-min exposure period, where a six-fold increase in Jabs was required for a corresponding effect in the in vivo bolus model. This illustrates that a rapid and robust effect of the AME is crucial to increase the in vivo intestinal absorption rate before the yet unabsorbed drug in lumen has been transported distally in the intestine. Further, the recovery of the intestinal mucosa was complete following 15-min exposures of SDS and chitosan, but it only recovered 50% after the 60-min intestinal exposures. Our study also showed that the luminal exposure of AMEs affected the absorptive model drug transport more than the excretion of 51Cr-EDTA, as Jabs for the drugs was more sensitive than CLCr at detecting dynamic mucosal AME effects, such as response rate and recovery. Finally, there appears to be no nicotinergic neural contribution to the absorption-enhancing effect of SDS and chitosan, as luminal administration of 0.1 mM mecamylamine had no effect.

Effect of absorption-modifying excipients, hypotonicity, and enteric neural activity in an in vivo model for small intestinal transport.

The small intestine mucosal barrier is physiologically regulated by the luminal conditions, where intestinal factors, such as diet and luminal tonicity, can affect mucosal permeability. The intestinal barrier may also be affected by absorption-modifying excipients (AME) in oral drug delivery systems. Currently, there is a gap in the understanding of how AMEs interact with the physiological regulation of intestinal electrolyte transport and fluid flux, and epithelial permeability. Therefore, the objective of this single-pass perfusion study in rat was to investigate the effect of three AMEs on the intestinal mucosal permeability at different luminal tonicities (100, 170, and 290 mOsm). The effect was also evaluated following luminal administration of a nicotinic receptor antagonist, mecamylamine, and after intravenous administration of a COX-2 inhibitor, parecoxib, both of which affect the enteric neural activity involved in physiological regulation of intestinal functions. The effect was evaluated by changes in intestinal lumen-to-blood transport of six model compounds, and blood-to-lumen clearance of 51Cr-EDTA (a mucosal barrier marker). Luminal hypotonicity alone increased the intestinal epithelial transport of 51Cr-EDTA. This effect was potentiated by two AMEs (SDS and caprate) and by parecoxib, while it was reduced by mecamylamine. Consequently, the impact of enteric neural activity and luminal conditions may affect nonclinical determinations of intestinal permeability. In vivo predictions based on animal intestinal perfusion models can be improved by considering these effects. The in vivo relevance can be increased by treating rats with a COX-2 inhibitor prior to surgery. This decreases the risk of surgery-induced ileus, which may affect the physiological regulation of mucosal permeability.

The effects of three absorption-modifying critical excipients on the in vivo intestinal absorption of six model compounds in rats and dogs.

Pharmaceutical excipients that may affect gastrointestinal (GI) drug absorption are called critical pharmaceutical excipients, or absorption-modifying excipients (AMEs) if they act by altering the integrity of the intestinal epithelial cell membrane. Some of these excipients increase intestinal permeability, and subsequently the absorption and bioavailability of the drug. This could have implications for both the assessment of bioequivalence and the efficacy of the absorption-enhancing drug delivery system. The absorption-enhancing effects of AMEs with different mechanisms (chitosan, sodium caprate, sodium dodecyl sulfate (SDS)) have previously been evaluated in the rat single-pass intestinal perfusion (SPIP) model. However, it remains unclear whether these SPIP data are predictive in a more in vivo like model. The same excipients were in this study evaluated in rat and dog intraintestinal bolus models. SDS and chitosan did exert an absorption-enhancing effect in both bolus models, but the effect was substantially lower than those observed in the rat SPIP model. This illustrates the complexity of the AME effects, and indicates that additional GI physiological factors need to be considered in their evaluation. We therefore recommend that AME evaluations obtained in transit-independent, preclinical permeability models (e.g. Ussing, SPIP) should be verified in animal models better able to predict in vivo relevant GI effects, at multiple excipient concentrations.

Very long-term Voice Handicap Index Voice Outcomes after Montgomery Thyroplasty: A cross-sectional study.

OBJECTIVE: The aim of this multicentric cross-sectional study was to examine the permanency of Montgomery thyroplasty (MTIS) results from a patient's perspective. DESIGN: The study consisted of collecting Voice Handicap Index (VHI-30) questionnaires from patients who had previously been operated with MTIS between 2 and 12 years before. Very long-term (>2 years) postoperative data were compared with the previously acquired preoperative and early postoperative VHI results. Influence of factors such as age, gender, size/side of the prosthesis and length of the follow-up were also analysed. SETTING: Multicentric study involving three tertiary European voice centres. PARTICIPANTS: Forty-nine unilateral vocal fold paralysis (UVFP) patients, treated by MTIS, were included in the study. MAIN OUTCOME MEASURES: The Voice Handicap Index-30 score. RESULTS & CONCLUSIONS: The median VHI was significantly different over time-points (Friedman's test P < .001), with a significant difference between preoperative and early postoperative time-points (median VHI: 70 vs 21, respectively; P < .001) and between preoperative and very long-term postoperative time-points (median VHI: 70 vs 16, respectively; P < .001). The median VHI did not differ for the early and very long-term postoperative time-points (median VHI: 21 vs 16; P = .470). Age differences, gender differences and size/side differences of the prostheses, centres where surgery took place and length of the follow-up showed no significant influence. Medialisation thyroplasty (MT) overall and MTIS, in particular, should be considered as a possible standard of care for UVFP when permanency of voice results is sought.

Clinical testing of three novel transient receptor potential cation channel subfamily V member 1 antagonists in a pharmacodynamic intradermal capsaicin model.

BACKGROUND: The transient receptor potential cation channel subfamily V 1 (TRPV1) is involved in nociception and has thus been of interest for drug developers, as a target for novel analgesics. However, several oral TRPV1 antagonists have failed in development, and novel approaches to target TRPV1 with innovative chemistry are needed. METHOD: This work describes an intradermal microdosing approach in humans for pharmacodynamic deductions and pharmacological profiling of compounds. First, a human capsaicin model was developed, to generate pharmacodynamic translational data (Study Part A, n = 24). Then, three small molecule TRPV1 antagonists (AZ11760788, AZ12048189 and AZ12099548) were investigated in healthy volunteers (Study Part B, n = 36), applying the established model. Pain and flare were assessed by Visual Analogue Score and laser Doppler, respectively. RESULTS: The developed model proved useful for pharmacologic deductions; all compounds caused a dose-dependent inhibition of capsaicin-induced pain and flare responses, with a rank order potency of AZ11760788 > AZ12048189 â‰« AZ12099548. In addition, the dose-response data showed that the minimal antagonist concentrations needed to inhibit TRPV1 was ≥6-7 times the equilibrium dissociation constant for each compound. CONCLUSION: With careful design of a pharmacodynamic translational human pain model, it was possible to rank order TRPV1 efficacy among three investigational TRPV1 antagonists, and to estimate human efficacious concentrations. SIGNIFICANCE: This fast and cost-effective translational approach allows for generation of human target engagement information early in drug development. This could be of value for other development programmes where pharmacological targets are expressed in peripheral sensory nerves.

Preclinical characterization of three transient receptor potential vanilloid receptor 1 antagonists for early use in human intradermal microdose analgesic studies.

BACKGROUND: The transient receptor potential vanilloid receptor 1 (TRPV1) is a nonselective cation channel involved in the mediation of peripheral pain to the central nervous system. As such, the TRPV1 is an accessible molecular target that lends itself well to the understanding of nociceptive signalling. This study encompasses preclinical investigations of three molecules with the prospect to establish them as suitable analgesic model compounds in human intradermal pain relief studies. METHODS: The inhibitory effectiveness was evaluated by means of in vitro assays, TRPV1 expressing Chinese hamster ovary cells (CHO-K1) and rat dorsal root ganglion cultures in fluorescent imaging plate reader and whole cell patch clamp systems, as well as in vivo by capsaicin-evoked pain-related behavioural response studies in rat. Secondary pharmacology, pharmacokinetics and preclinical safety were also assessed. RESULTS: In vitro, all three compounds were effective at inhibiting capsaicin-activated TRPV1. The concentration producing 50% inhibition (IC50 ) determined was in the range of 3-32 nmol/L and 10-501 nmol/L using CHO-K1 and dorsal root ganglion cultures, respectively. In vivo, all compounds showed dose-dependent reduction in capsaicin-evoked pain-related behavioural responses in rat. None of the three compounds displayed any significant activity on any of the secondary targets tested. The compounds were also shown to be safe from a toxicological, drug metabolism and pharmacokinetic perspective, for usage in microgram doses in the human skin. CONCLUSION: The investigated model compounds displayed ideal compound characteristics as pharmacological and translational tools to address efficacy on the human native TRPV1 target in human skin in situ. SIGNIFICANCE: This work details the pharmaceutical work-up of three TRPV1-active investigational compounds, to obtain regulatory approval, for subsequent use in humans. This fast and cost-effective preclinical development path may impact research beyond the pain management area, as it allows human target engagement information gathering early in drug development.

Voice outcome indicators for unilateral vocal fold paralysis surgery: a review of the literature.

INTRODUCTION: There is no consensus on which voice outcome indicators (VOIs) should be used to compare the merits of the various surgical treatments for unilateral vocal fold paralysis (UVFP). Authors performed a literature review to identify which VOIs are most frequently used and most relevant, in terms of significant change in pre- and post-operative measurements, to assess UVFP surgical treatments. METHOD: A Medline/Pubmed literature review was performed and the most frequently used VOIs were identified using a Pareto diagram. For these most frequently used VOI's, the number of studies that showed a statistically significant change in pre- and post-operative results were compared to the total number of studies found using that same VOI, this portion was expressed in percent. This percentage was defined as the "percentage of significance" and used to assess changes of each VOI. RESULTS: Eleven VOIs were identified using the Pareto analysis. These were, in decreasing order of frequency of citation: maximum phonation time (MPT), jitter, Shimmer, video-stroboscopic examination, noise to harmonic ratio (NHR/HNR), mean air flow (MeAF), fundamental frequency (F0), "Infrequent Perceptional Scales", GRBAS scale, mean subglottic pressure (MSGP). MPT, MeAF, factor G of GRBAS-I, Jitter, shimmer and VHI-30 had respective "percentage of significance" of 90, 86, 85, 74, 68 and 64%, respectively. CONCLUSION: The results indicate that MPT, MeAF and GRBAS-I, represent the top-three most frequently used and the most relevant VOIs in terms of "percentage of significance". VHI-30 showed a relatively low rate of use and low "percentage of significance". The role of Jitter and Shimmer remains unclear. Finally, MSGP and the F0 appear to be less relevant VOIs for the evaluation of UFVP surgical treatments in terms of significant change in pre- and post-operative measurements.

Transoral Laser Microsurgery in Early Glottic Lesions.

PURPOSE OF REVIEW: To give an overview of the evolvement of transoral laser microsurgery (TLM) in the treatment of early glottic carcinoma and highlight the contribution of recent literature. RECENT FINDINGS: The indications and limits of TLM have been well specified. Effects on swallowing have been well documented. Introduction of narrow-band imaging (NBI) and diffusion-weighted magnetic resonance has been shown of additional value for outcome. The first reports on transoral robotic surgery show that it may be of added value in the future. SUMMARY: TLM for early glottic carcinoma (Tis-T2) has very good oncological outcomes with indications of higher larynx preservation in TLM than that in radiotherapy. The anterior commissure is a risk factor if involved in the cranio-caudal plane, and reduced vocal fold mobility is a risk factor when this is due to arytenoid involvement. The best voice results are achieved when the anterior commissure can be left intact along with part of the vocal fold muscle although even in larger resections, patient self-reported voice handicap is still limited.

Computational fluid dynamics (CFD) studies of a miniaturized dissolution system.

Dissolution testing is an important tool that has applications ranging from fundamental studies of drug-release mechanisms to quality control of the final product. The rate of release of the drug from the delivery system is known to be affected by hydrodynamics. In this study we used computational fluid dynamics to simulate and investigate the hydrodynamics in a novel miniaturized dissolution method for parenteral formulations. The dissolution method is based on a rotating disc system and uses a rotating sample reservoir which is separated from the remaining dissolution medium by a nylon screen. Sample reservoirs of two sizes were investigated (SR6 and SR8) and the hydrodynamic studies were performed at rotation rates of 100, 200 and 400rpm. The overall fluid flow was similar for all investigated cases, with a lateral upward spiraling motion and central downward motion in the form of a vortex to and through the screen. The simulations indicated that the exchange of dissolution medium between the sample reservoir and the remaining release medium was rapid for typical screens, for which almost complete mixing would be expected to occur within less than one minute at 400rpm. The local hydrodynamic conditions in the sample reservoirs depended on their size; SR8 appeared to be relatively more affected than SR6 by the resistance to liquid flow resulting from the screen.