A Microfluidic Device for Imaging Samples from Microbial Suspension Cultures.

Traditional methods to assess microbial cells during suspension culture require laborious and frequent manual sampling. Approaches to automate sampling and assessment utilize dedicated, sophisticated equipment and suffer from a lack of temporal resolution and sampling efficiency. In this study we describe a simple microfluidic device that allows microbial cells to be sampled from suspension culture and rapidly slowed and concentrated for single-cell imaging on a standard laboratory microscope. We demonstrate a device that: •slows and concentrates microbial cells, specifically budding yeast, sampled from suspension culture and improves imaging of individual cells by concentrating them in a single focal plane•provides imaging quality and temporal resolution that is capable of monitoring dynamic spatiotemporal processes, such as nuclear localization of a protein•is inexpensive and simple enough to be fabricated and used in laboratories equipped for standard molecular and cellular biology.

Validation and Evaluation of the Effects of Semi-Occluded Face Mask Straw Phonation Therapy Methods on Aerodynamic Parameters in Comparison to Traditional Methods.

OBJECTIVES/HYPOTHESIS: Traditional semi-occluded vocal tract therapies have the benefit of improving vocal economy but, do not allow for connected speech during rehabilitation. In this study, we introduce a semi-occluded face mask (SOFM) as an improvement upon current methods. This novel technique allows for normal speech production, and will make the transition to everyday speech more natural. We hypothesize that use of an SOFM will lead to the same gains in vocal economy seen in traditional methods. STUDY DESIGN: Repeated measures excised canine larynx bench experiment with each larynx subject to controls and a randomized series of experimental conditions. METHODS: Aerodynamic data were collected for 30 excised canine larynges. The larynges were subjected to conditions including a control, two tube extensions (15 and 30 cm), and two tube diameters (6.5 and 17 mm) both with and without the SOFM. Results were compared between groups and between conditions within each group. RESULTS: No significant differences were found between the phonation threshold pressure and phonation threshold flow measurements obtained with or without the SOFM throughout all extension and constriction levels. Significant differences in phonation threshold pressure and phonation threshold flow were observed when varying the tube diameter while the same comparison for varying the tube length at least trended toward significance. CONCLUSIONS: This study suggests that a SOFM can be used to elicit the same gains in vocal economy as what has been seen with traditional semi-occluded vocal tract methods. Future studies should test this novel technique in human subjects to validate its use in a clinical setting.

Validation of the laryngopharyngeal reflux color and texture recognition compared to pH-probe monitoring.

OBJECTIVE/HYPOTHESIS: The objective of this study was to determine the validity of our laryngopharyngeal reflux (LPR) diagnostic system from our previous study (Witt et al.) against the results of a standard pH probe monitoring. We hypothesized that subjects with abnormal pH probe results demonstrate color and texture abnormalities that would be classified as LPR according to artificial neural network (ANN) analysis. STUDY DESIGN: Retrospective analysis. METHODS: Eighty-two subjects, including 18 pH-positive, 11 pH-negative, and 53 control subjects were tested for LPR through multichannel intraluminal impedance 24-hour pH (MII-24pH) monitoring. Laryngoscopic images of all subjects were obtained. The hue and texture values of seven areas of interest, including true vocal folds, false vocal folds, arytenoids, and interarytenoid, were quantified using a hue calculation and two-dimensional Gabor filtering. These served as inputs for the ANN. This was used to classify images through pattern recognition, and a receiver operating characteristic (ROC) analysis was performed to determine the effectiveness of the diagnosis. RESULTS: Classification accuracy for the combined hue and texture was 87.40%, with an area under the ROC curve of 0.910. CONCLUSION: Although a previous study conducted classification based on RFS, this study suggests that color and texture analysis may be used to classify images based on the results of pH probing, a more objective approach for diagnosis. Additional studies should include more subjects to produce an even more accurate reading, and will use the color/texture analysis tool to test and confirm this application in a clinical setting. LEVEL OF EVIDENCE: 3B. Laryngoscope, 127:665-670, 2017.

Development of an Innovative 3D Printed Rigid Bronchoscopy Training Model.

OBJECTIVES: The objective of this study was to create a 3D printed airway model simulating the size and mechanical properties of various age groups for foreign body removal training. METHODS: Three-dimensional printing technology was used to print the anatomically correct airway from rubber-like translucent material, simulating the mechanical properties of human airway tissue. The model's effectiveness in trainee education was evaluated by otolaryngology residents with varying levels of experience. As part of an Airway Emergencies course, a rigid bronchoscopy procedure was performed on the 3D printed model as well as a porcine model. The participants completed surveys comparing the validity of the 2 models and the effectiveness of the overall training experience. RESULTS: The 3D printed model, which is accurate in terms of anatomy and mechanical properties, was found to be comparable to a porcine model in regards to participant satisfaction as well as face validity. CONCLUSIONS: The 3D printed airway model is able to be accurately scaled to various sizes and simulate the mechanical properties of the desired age group. The 3D printed model provides an excellent alternative to animal models in terms of practicality, logistics of use, and anatomical accuracy.