Allen Foulad

Automated audiometry using apple iOS-based application technology.

Objective The aim of this study is to determine the feasibility of an Apple iOS-based automated hearing testing application and to compare its accuracy with conventional audiometry. Study Design Prospective diagnostic study. Setting Academic medical center. Subjects and Methods An iOS-based software application was developed to perform automated pure-tone hearing testing on the iPhone, iPod touch, and iPad. To assess for device variations and compatibility, preliminary work was performed to compare the standardized sound output (dB) of various Apple device and headset combinations. Forty-two subjects underwent automated iOS-based hearing testing in a sound booth, automated iOS-based hearing testing in a quiet room, and conventional manual audiometry. Results The maximum difference in sound intensity between various Apple device and headset combinations was 4 dB. On average, 96% (95% confidence interval [CI], 91%-100%) of the threshold values obtained using the automated test in a sound booth were within 10 dB of the corresponding threshold values obtained using conventional audiometry. When the automated test was performed in a quiet room, 94% (95% CI, 87%-100%) of the threshold values were within 10 dB of the threshold values obtained using conventional audiometry. Under standardized testing conditions, 90% of the subjects preferred iOS-based audiometry as opposed to conventional audiometry. Conclusion Apple iOS-based devices provide a platform for automated air conduction audiometry without requiring extra equipment and yield hearing test results that approach those of conventional audiometry.

Imaging vibrating vocal folds with a high speed 1050 nm swept source OCT and ODT

Vocal fold vibration is vital in voice production and the correct pitch of speech. We have developed a high speed functional optical coherence tomography (OCT) system with a center wavelength of 1050 nm and an imaging speed of 100,000 A-lines per second. We imaged the vibration of an ex-vivo swine vocal fold. At an imaging speed of 100 frames per second, we demonstrated high quality vocal fold images during vibration. Functional information, such as vibration frequency and vibration amplitude, was obtained by analyzing the tissue surface during vibration. The axial direction velocity distribution in the cross-sectional images of the vibrating vocal folds was obtained with the Doppler OCT. The quantitative transverse direction velocity distribution in the cross-sectional images was obtained with the Doppler variance images.

Stabilization of Costal Cartilage Graft Warping Using Infrared Laser Irradiation in a Porcine Model

OBJECTIVE To develop a method to rapidly stabilize the shape change process in peripheral slices of costal cartilage by using infrared laser irradiation in a porcine model. METHODS Forty peripheral porcine costal cartilage specimens (40 × 10 × 2 mm) were harvested. Thirty of these specimens were immediately irradiated with an Nd:YAG laser (λ = 1.32 μm; spot size, 2-mm diameter) using 1 of 3 exposure treatments: 6 W, 2 seconds, and 4 spots; 8 W, 3 seconds, and 4 spots; or 6 W, 2 seconds, and 8 spots. Ten control specimens were only immersed in 0.9% saline solution. Angle of curvature was measured from photographs taken at 0 minutes, immediately after irradiation, and at 30 minutes, 1 hour, 5 hours, and 24 hours. Infrared imaging was used to measure surface temperatures during irradiation. Cell viability after irradiation was determined using a live/dead assay in conjunction with fluorescent confocal microscopy. RESULTS Compared with the untreated controls, the irradiated grafts underwent accelerated shape change within the first 30 minutes to reach a stable geometry. Thereafter, irradiated grafts underwent little or no shape change, whereas the control group exhibited significant change in curvature from 30 minutes to 24 hours (P < .001). The average peak irradiated spot temperatures ranged from 76°C to 82°C. Cell viability measurements at the laser spot sites demonstrated a hemispherically shaped region of dead cells with a depth of 0.8 to 1.2 mm and a surface diameter of 1.9 to 2.7 mm. CONCLUSIONS Laser irradiation of peripheral costal cartilage slices provides an effective method for rapidly stabilizing acute shape change by accelerating the warping process. The temperature elevations necessary to achieve this are spatially limited and well within the limits of tolerable tissue injury.

Electromechanical Reshaping of Costal Cartilage Grafts: A New Surgical Treatment Modality

Needle electrode‐based electromechanical reshaping (EMR) is a novel, ultra‐low‐cost nascent surgical technology to reshape cartilage with low morbidity. EMR uses direct current to induce mechanical relaxation in cartilage that is first deformed into a required geometry, which in turn leads to permanent shape change. The objective of this study was to determine the effect of EMR voltage and time on the shape change of costal cartilage grafts.

Practical Device for Precise Cutting of Costal Cartilage Grafts to Uniform Thickness

OBJECTIVES Costal cartilage is becoming increasingly popular as a graft source for facial reconstruction. However, carving methods have not changed in decades and continue to primarily rely on detailed maneuvers with a scalpel. There are few reports of mechanical devices for shaping costal cartilage, and to our knowledge their accuracy and precision have not been reported. We describe a simple costal cartilage slicing device that facilitates the production of sections having uniform, user-defined thicknesses. METHODS The design included laboratory research using 200 porcine and 2 cadaveric human ex vivo costal cartilage slices. A 2-component apparatus was constructed consisting of a mechanism to secure the costal cartilage and a double-bladed device to cut the rib graft through a central cross-section. Optimizing blade characteristics and static forces that secure the cartilage were critical design challenges. The device was used to obtain slices 0.8, 2.1, and 4.1 mm in thickness, with lengths up to 4.0 cm and a width of 1.0 cm. To confirm uniformity, thickness was measured at 8 fixed regions per section using a digital micrometer. RESULTS All costal cartilage slices appeared to be extremely uniform on visual and manual inspection. The absolute difference between the largest and smallest thickness measured for each individual sample ranged from 0.04 to 0.13 mm, 0.06 to 0.14 mm, and 0.10 to 0.21 mm for the 0.8-, 2.1-, and 4.1-mm-thick groups, respectively. CONCLUSIONS Our study demonstrates the precision of using a mechanical slicing device to section costal cartilage to a clinically relevant and uniform thickness. This mechanized technology may increase accuracy and reduce carving time required for using costal cartilage tissue in head and neck reconstruction.

A Novel Device for Measurement of Subglottic Stenosis in 3 Dimensions During Suspension Laryngoscopy

IMPORTANCE A challenge in treating subglottic stenosis is assessment of airway caliber before and after management. At present, surgeons lack a simple, efficient, and precise method of measuring subglottic stenosis intraoperatively. We present a novel, easily reproducible tool for measurement of the diameter, location, and length of subglottic stenosis during suspension laryngoscopy. METHODS AND OBSERVATIONS A set of 5 Kirschner wires (30-cm length and 1.6-mm diameter) were bent 90° at both ends to produce a series of 10 short ends designed to measure airway diameter (0.3- to 2.1-cm length with 2-mm intervals). Short, bent ends of the measuring sticks were designed to measure airway diameter. Hash marks at 2-mm intervals were created along the long axis of the measuring sticks to measure subglottic stenosis length and location relative to the vocal cords. The measuring stick was tested in 10 adult patients undergoing suspension microlaryngoscopy for endoscopic treatment of subglottic stenosis between September 2012 and July 2013. The accuracy of the measuring stick was evaluated using an airway phantom. The measuring stick enabled easy and precise quantification of subglottic stenosis diameter (82.5% agreement with reference; interobserver agreement, r = 0.995; P < .001), length (72.5%; r = 0.995; P < .001) and location during suspension laryngoscopy. CONCLUSIONS AND RELEVANCE The measuring stick is inexpensive and simple to construct. It allows for safe, accurate, and practical measurement of subglottic stenosis diameter, length, and location during suspension laryngoscopy.

Precise and Rapid Costal Cartilage Graft Sectioning Using a Novel Device: Clinical Application

IMPORTANCE The use of costal cartilage as a graft in facial reconstructive surgery requires sectioning the cartilage into a suitable shape. OBJECTIVE To evaluate the accuracy of a novel mechanical device for producing uniform slices of costal cartilage and to illustrate the use of the device during nasal surgery. DESIGN Basic and clinical study using 100 porcine ex vivo costal cartilage slices and 9 operative cases. METHODS This instrument departs from antecedent devices in that it uses compression to secure and stabilize the specimen during sectioning. A total of 75 porcine costal cartilage ribs were clamped with minimal compression just sufficient to secure and stabilize the specimen while cutting. Slices having a length of 4 cm and width of 1 cm were obtained using the cartilage cutter at 3 thicknesses: 1 mm (n = 25), 2 mm (n = 25), and 3 mm (n = 25). The procedure was repeated for the 2-mm thick samples; however, the ribs in this group (n = 25) were clamped using the maximum amount of compression attainable by the device. Thickness was measured using a digital micrometer. Case presentations illustrate the use of the device in secondary and reconstructive rhinoplasty surgery. RESULTS All specimens were highly uniform in thickness on visual inspection and appeared to be adequate for clinical application. Sectioning was completed in several seconds without complication. In the porcine specimens sectioned using minimal compression, the percentage difference in thickness for each individual sample averaged 18%, 10%, and 11% for the 1-mm-, 2-mm-, and 3-mm-thick slices, respectively. Within the specimens sectioned using maximum compression, the percentage difference in thickness for each individual sample averaged 35% for the 2-mm-thick slices. In the setting of nasal reconstructive surgery, slices having a thickness from 1 to 2 mm were found to be well suited for all necessary graft types. CONCLUSIONS AND RELEVANCE The simple mechanical device described produces costal cartilage graft slices with highly uniform thickness. Securing the rib by clamping during cutting reduces uniformity of the slices; however, the imperfections are minimal, and all sectioned grafts are adequate for clinical application. The device can be adjusted to produce slices of appropriate thickness for all nasal cartilage grafts. This device is valuable for reconstructive procedures owing to its ease of use, rapid operation, and reproducible results.

Modular Component Assembly Approach to Microtia Reconstruction.

BACKGROUND Current methods of microtia reconstruction include carving an auricular framework from the costal synchondrosis. This requires considerable skill and may create a substantial defect at the donor site. OBJECTIVE To present a modular component assembly (MCA) approach that minimizes the procedural difficulty with microtia repair and reduces the amount of cartilage to a single rib. DESIGN, SETTING, AND PARTICIPANTS Ex vivo study and survey. A single porcine rib was sectioned into multiple slices using a cartilage guillotine, cut into components outlined by 3-dimensional printed templates, and assembled into an auricular scaffold. Electromechanical reshaping was used to bend cartilage slices for creation of the helical rim. Chondrocyte viability was confirmed using confocal imaging. Ten surgeons reviewed the scaffold constructed with the MCA approach to evaluate aesthetics, stability, and clinical feasibility. The study was conducted from June 5 to December 18, 2014. MAIN OUTCOMES AND MEASURES The primary outcome was creation of a modular component assembly method that decreases the total amount of rib needed for scaffold construction, as well as overall scaffold acceptability. The surgeons provided their assessments through a Likert-scale survey, with responses ranging from 1 (disagree with the statement) to 5 (agree with the statement). Thus, a higher score represents that the surgeon agrees that the scaffold is structurally and aesthetically acceptable and feasible. RESULTS An auricular framework with projection and curvature was fashioned from 1 rib. The 10 surgeons who participated in the survey indicated that the MCA scaffold would meet minimal aesthetic and anatomic acceptability. When embedded under a covering, the region of the helix and antihelix of the scaffold scored significantly higher on the assessment survey than that of an embedded alloplast implant (mean [SD], 4.6 [0.97] vs 3.5 [1.27]; P = .007). Otherwise, no significant difference was found between the embedded MCA and alloplast implants (4.42 [0.48] vs 3.87 [0.41]; P = .13). Cartilage prepared with electromechanical reshaping was viable. CONCLUSIONS AND RELEVANCE This study demonstrates that 1 rib can be used to create an aesthetic and durable framework for microtia repair. Precise assembly and the ability to obtain thin, uniform slices of cartilage were essential. This cartilage-sparing MCA approach may be an alternative to classic techniques. LEVEL OF EVIDENCE NA.

Lateral Crural Tensioning for Refinement of the Nasal Tip and Increasing Alar Stability: A Case Series

Abstract The objective of this study was to discuss the technical details and our experiences with lateral crural tensioning (LCT) in both functional and aesthetic rhinoplasties. A retrospective medical review was completed for all patients who underwent rhinoplasty with LCT from the years 2011 to 2014. The indications for LCT included correction of lateral crural convexity, boxy tip geometry, and dynamic collapse of the external nasal valve. The details of the rhinoplasty procedure and complications were evaluated. A total of 114 LCT rhinoplasty cases were included in this series. The most common adjunctive maneuvers included placement of spreader grafts (92% of cases) and alar rim grafts (78% of cases). Conventional classic cephalic trim was not performed in any subjects and conservative paradomal cephalic trim was performed in 48% of cases. As experience with the technique progressed, the use of onlay tip grafts decreased and the use of articulated rim grafts increased. Indications for revision were dissatisfaction with cosmetic outcome (4.4% of cases) and nasal obstruction (0.9% of cases). LCT combines traditional lateral crural steal with the use of a caudal septal extension graft to refine the broad tip and increase stability of the alar lobule. This maneuver is essentially cartilage sparing and does not rely on extensive grafting maneuvers that can reduce airway area.

VOCALSS: Versatile optimally constructed aid for laryngeal surgery simulation.

INTRODUCTION Surgical training traditionally relies on acquired proficiency in the operating room; however, this approach may be inadequate in the setting of laryngeal surgery. The narrow field of view and single-operator nature of various laryngeal procedures make guidance and control by the senior mentor difficult. Furthermore, because a number of laryngeal procedures are performed on awake patients, practice and tutorial are often limited due to a concern for patient discomfort and anxiety. Low case volume and resident work-hour restrictions can also limit operative exposure and further hamper surgical education. The challenges associated with laryngeal surgical training highlight the importance of supplemental education and practice outside of the operating room. In a survey-based study by Shah et al. (2013), the majority of senior resident physicians were not satisfied with their phonomicrosurgical experience and felt that their comfort level would increase if laboratory-based training was more accessible. The use of simulation models has been shown to significantly increase comfort level for performing vocal cord injections via suspension microlaryngoscopy and per-oral techniques. In addition, Contag et al. (2009) demonstrated that training simulators improve trainees’ ability to dissect vocal cord lesions from a synthetic larynx. In their study, novice trainees had a significant reduction in superficial peripheral injury and required decreased time to complete the excision after using the simulator. Demand for a simulated surgical environment prompted the publication of laryngeal dissection textbooks and the development of multiple laryngeal dissection station models. Paczona (1997) was among the first in the literature to describe a cadaver larynx holder for practicing microsurgery. Designed solely for endolaryngeal procedures, its construction involves using custom-cut sheets of wood and a suspension laryngoscope. Subsequently, a custom larynx holder was described specifically for laser use. More versatile laryngeal dissection stations that enable the practice of both endolaryngeal and open procedures have also been reported. Although previously described simulators have improved the practice of laryngeal surgery, there is a need for further progress. Currently, simulator stations are not commercially available and are not easily accessible. The construction of these apparatuses requires machine shop expertise or involves the use of parts that are uncommon or expensive. Previously described devices have been reported to cost