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1.IntroductionMiddle-ear infections, commonly known as otitis media (OM), affect more than 80% of children.1 Current studies estimate the diagnostic accuracy for OM by an expert physician using standard otoscopy at 60% to 70%.2 Existing technology used to diagnose OM is limited primarily to illumination and magnification devices,3 such as otoscopes or surgical microscopes, which only provide a surface view of tissue. Diagnosis using these tools relies on accurately interpreting visual features of the tympanic membrane (TM) or the accurate detection of the presence of any middle-ear effusion (MEE). Pneumatic otoscopy, while considered the gold standard for OM diagnosis, is difficult to perform correctly and is often not utilized in daily clinical practice.4 Other acoustic techniques, such as tympanometry and acoustic reflectometry, provide additional insight into the functional behavior of the TM and middle-ear mobility. While tympanometry can help to infer middle-ear dysfunction and provide slightly improved diagnostic accuracy over otoscopy alone, tympanometry results are still recommended to be considered alongside otoscopy findings.5 Persistent or recurrent cases of OM are treated with tympanostomy tube (TT) placement, one of the most commonly performed surgeries in children requiring general anesthesia.6,7 While of all children in the US will receive TT before the age of 2, there are reports that physicians often inconsistently recommend TT placement when verified against treatment guidelines,8 although varying subpopulations and differing treatment implementation strategies across the US explain this variance.8–12 This study is motivated by previous efforts that used optical coherence tomography (OCT), a noninvasive and high-resolution medical imaging technology, to visualize the TM and middle ear. Past studies have used OCT in surgical settings,13–15 although its use has previously been limited mainly to ex vivo16–19 tissue due to technical challenges and physical limitations of light delivery to the ear. Our group has addressed many of these challenges and performed both animal7,20 and human6,21–25 studies. Recently, one study21 identified and visualized additional infection-related structures affixed to the TM in nearly every case of chronic OM, which led to our current interest to understand longitudinal changes in the observed structures following surgical intervention. The pathogenesis of these additional infection-related structures observed in OCT images is unclear. Yet, the presence of biofilms during infection in the respiratory tract and upper airway, including the adenoids and middle-ear cavity (MEC), is understood and well established.20,26–34 There remains, however, a lack of understanding of the specific role that biofilms play during “healthy” or “infected” conditions in the middle ear, as previously it has not been possible to regularly and longitudinally observe these biofilms in vivo. Biofilms are communities of bacteria enclosed in a self-produced extracellular polymeric substance.35 Biofilms protect bacteria from host immune response mechanisms36–43 and antibiotic treatments. Given the possible virulence, persistence, and/or recurrence of biofilm-associated infection in the ear, understanding the mechanisms that drive the infection process was recently declared a grand challenge in pediatric otolaryngology.44 In this study, an OCT system combined with video-based surface imaging of the TM was used to prospectively observe patients through consecutive preoperative, surgical, and postoperative visits to quantitatively characterize and assess the efficacy of surgical TT placement to clear middle-ear infection. It is expected that a patient with a successful surgical intervention would have no further clinical symptoms, and OCT images would be clear of any image-based features that would be associated with OM, including any MEE or biofilm. In the presence of persistent or recurrent clinical symptoms of OM, we expect to find OCT image evidence of persistent or recurrent MEE and/or middle-ear biofilm. 2.Materials and Methods2.1.Subject Population and RecruitmentSubjects were recruited from the outpatient pediatric population of Urbana-Champaign, Illinois, visiting Carle Foundation Hospital for treatment in the Department of Otolaryngology. Twenty-five25 subjects were prospectively observed at both secondary care and outpatient surgical centers for months, with 6 months of additional medical record-based follow-up. Subjects were imaged with OCT at up to three possible time points in their treatment: (1) patient evaluation and preoperative surgical consultation, (2) surgery (intraoperative imaging), and (3) postoperative follow-up. All participants provided informed consent and assent in accordance with protocols approved by the institutional review boards of Carle Foundation Hospital and the University of Illinois at Urbana-Champaign. The standard-of-care treatment provided was according to recommended national treatment guidelines for acute OM,45 OM with effusion (OME),46 and TT placement.47 Subjects diagnosed with chronic or recurrent OM and participating in this study had, at a minimum, multiple infections within a 3- to 6-month time period and/or a persistent MEE for 3 months, as well as concerns about hearing, speech, and/or cognitive development. All subjects were years of age and were excluded if their temperament or discomfort prohibited imaging with the handheld OCT probe. No exclusions were made based on gender or race. 2.2.Handheld Probe and Portable OCT SystemA custom-built handheld probe and portable OCT system (Fig. 1) were used to image subjects. The system utilized a broadband optical source (Superlum, Ireland) centered at 860 nm with an approximate bandwidth of 135 nm at full width at half maximum, which provided an axial resolution of and a transverse resolution of , in air. A line scan camera-based spectrometer (Wasatch Photonics) provided data to process cross-sectional B-mode images. The OCT system emitted an optical power of 2.5 mW onto the TM, which is well below ANSI standard safety limits.48 A separate, commercial video otoscope (Welch Allyn) was used to document surface images of the TM. Additional details regarding the system can be found in a prior publication.49 2.3.Image Collection ProtocolThe imaging protocol aimed to minimize any interruption to the standard-of-care examination procedures at each imaging site and ensure that pediatric subjects would remain as calm and attentive as possible to minimize artifacts in the collected data. At each imaging time point, the handheld probe was inserted into the ear canal and positioned to bring the TM into the field of view. The light reflex region of the TM was then identified and observed with OCT, using the malleus and umbo as anatomical landmarks for positioning. The OCT system utilized a buffer to constantly process and display images for real-time viewing, with a trigger on the handheld probe to save images. Depressing the trigger stored the 40 most recently visualized OCT images for later analysis. Multiple stacks of B-scans were typically acquired at each time point, which later allowed a representative image to be selected for analysis. In place of saving all visualized data or needing to manipulate on-screen buttons to initiate saving, the use of a constantly updating buffer and trigger method allowed for more efficient collection of high-quality images. Primarily, this ensured that collected OCT images were taken from the light reflex region of the TM and avoided saving empty or unrelated images during positioning of the handheld probe in the ear canal and around any earwax that may have been present. This also allowed the operator to more successfully manage patient movement that occurs throughout the examination and limit the acquisition of images with artifacts when possible. OCT images were not interpreted or analyzed for content before or during collection. Physicians did not utilize OCT images for clinical decision-making. In the otolaryngology clinic, imaging was performed after regularly scheduled examinations, such that the physician could first formulate an unbiased treatment plan. During surgery, OCT imaging was performed intraoperatively after clearing of any cerumen, part of the standard-of-care procedure in this setting, and prior to myringotomy or TT placement. Otoscopic examination of the TM requires an unobscured line of sight through the ear canal, although a view that is not entirely clear of cerumen (ear wax) or small hairs is common. However, additional cerumen removal specifically to improve OCT imaging in the otolaryngology clinic was not performed. Standard-of-care practices in the clinic dictate that cerumen is removed only if there is a severe obstruction of the physicians’ view of the TM for otoscopy.50 Furthermore, cerumen removal incurs additional costs for the patient, estimated in 2012 to be USD.51 In either clinic or surgical setting, imaging both ears took . 2.4.Image Processing and Analysis ProtocolOCT image processing and analysis were performed by experienced readers familiar with OCT and OCT ear imaging, although there was no training specific to this study. Readers were provided with sequentially numbered OCT image stack files and digital otoscopy images from a single time point for analysis and were blinded to the imaging time point and clinical diagnoses during analysis. Images were removed from consideration and not analyzed if they contained artifacts (saturations, reflections, or wrapping), were acquired from the ear canal, positions on the TM other than the light reflex, or were out of focus. From the remaining set of images, a representative image that best demonstrated the overall findings from the time point was selected by the reader to maximize image quality and clarity for display and analysis. Representative images were analyzed to determine the presence or absence of a biofilm or MEE at each time point for each subject using methods determined in a previous publication.21 Quantitative features in OCT images that demonstrated the morphological changes of chronic OM include the presence of additional structures within the MEC, such as overall thickening due to the presence of biofilm or MEE, presenting as dense layered structures adhered to the TM, or point-like scatterers within the MEC, respectively. Clearly, defining the interior mucosal surface of the TM and interface between these additional structures can be difficult in some cases if refractive index matching occurs between the TM and middle-ear fluid or biofilm. Similarly, it may not be possible to visualize deeper into the MEC due to the highly scattering nature of more purulent middle-ear fluid. Structures external to the MEC and within the ear canal, such as earwax, were not considered and were mostly unrelated to OM infection status. After analysis, images were sorted into a secure repository and organized by subject number, date, and time point. Reports containing clinical diagnosis and findings were collected, organized, and analyzed separately from OCT data at a later time. For the purposes of this study, OCT imaging results were then analyzed in conjunction with findings from patient medical and/or surgical reports to correlate the presence or absence of a middle-ear biofilm with clinical symptoms of OM and patient outcomes. 3.ResultsTwenty-five subjects (Table 1) were imaged in this study, which concluded without any adverse events. Patient history was available for any performed examination or procedure. Risk factors indicate an increased likelihood of recurrent OM. Subjects were split into two groups: the “C” (complete) group, and “P” (partial) group. Six subjects in the C group (C1 to C6) were observed at all three time points: preoperative consultation, intraoperatively, and at the follow-up exam. Nineteen subjects in the P group (P1 to P19) were observed at the preoperative consultation visit and then either did not receive surgery (5/19), did not return for follow-up exam after surgery (5/19), or were unable to be imaged given scheduling conflicts (9/19), which is clarified in the “observed visits” column. The recurrence column indicates treatment outcome through any OM-related visit after surgery to the primary care or otolaryngology clinic, which are further described in the footnote of Table 1. Table 1Summary of imaging subjects and clinical history.
Note: Observed visits (1, 2, 3); ✓, attended and scanned participant; ×, participant did not attend; –, participant received treatment but OCT imaging was not performed; ABx, antibiotic; AOM, acute otitis media; ETD, Eustachian tube dysfunction; OME, otitis media with effusion; TT, tympanostomy tube; and URS, upper respiratory system. A simplified visual breakdown of subjects enrolled in this study is presented in Fig. 2, organized by the day of observation. All subjects presented initially with a history of recurrent OM or Eustachian tube dysfunction (ETD) and were observed throughout their treatment with OCT. On their day of preoperative consultation, 92% (23/25) of subjects had a biofilm identified with OCT. On the day of surgery, 11 subjects were observed with OCT, and 91% (10/11) of subjects had a biofilm identified with OCT immediately prior to surgical intervention. At the follow-up examination, six subjects returned for OCT imaging. These subjects were compliant with the study schedule and comprised the C (complete) group, with OCT data and clinical reports available from each time point. Of the subjects in the C group, two of six subjects had additional structures identified with OCT (subjects C4 and C5), and subject C5 reported recurrence issues of OM. In 67% (4/6) of subjects, surgery was effective at clearing symptoms of OM and had no biofilm identified with OCT. For the remaining 19 subjects that were noncompliant with the study schedule, only partial data was able to be collected. The P (partial) group included clinical reports and OCT data from the day of consultation and reports if/when care was received at a later unscheduled visit. While 8 of 19 subjects returned for all care, 88% (7/8) of subjects later reported persistent OM symptoms and had biofilm-like structures previously identified with OCT at an earlier visit. Six of 19 subjects did not return for follow-up care after receiving TT surgery during the study observation period. While follow-up visits and care are recommended as standard practice and included in the cost of surgery, one review found that only 25% of patients return for follow-up care, despite guidelines that recommend patients regularly follow-up with otolaryngologists until TT has extruded.52 While dependent on the type of TT used, most TTs safely extrude on their own within a year,53 though follow-up care may still be needed in the future if complications occur. Five of 19 subjects did not receive TT surgery or have a follow-up visit scheduled. In the C group, five out of six subjects (83%) had no recurrence of symptoms after TT surgery. In four out of six subjects, cross-sectional OCT images at the postoperative follow-up visit showed that the MEC was free of biofilm and MEE, although a biofilm had been visualized with OCT during the preoperative visit and intraoperatively during TT surgery. Figure 3 highlights a representative case where subject C3 presented with chronic OME and ETD and was prospectively imaged with OCT to identify changes following TT surgery. Figure 3(a) shows data from the first visit to the otolaryngology clinic (patient evaluation and preoperative consultation). Cross-sectional OCT shows a bright, scattering biofilm structure (green arrow) affixed to the medial mucosal surface of the TM, as well as evidence of suspended, optically scattering particles in the MEC, indicative of an MEE (white arrow, dashed). The corresponding video otoscope surface image shows a dull and relatively featureless TM (inset). Here, and in subsequent figures, yellow and green bars denote the location and thickness of the TM and biofilm, respectively, as determined using a previous method.21 Figure 3(b) shows intraoperative image data from this same subject and ear (second visit) prior to myringotomy, aspiration of the MEC, and TT placement. OCT imaging confirmed the persistence of infection-related image-based features, including the biofilm (green arrow, green line) and MEE (white arrow, dashed) imaged at the consultation visit, although scanned at a slightly different TM location within the light reflex region. Approximately one month later, the same subject was imaged at the third visit (postoperative follow-up) following standard postsurgical care. Here, the microstructural effects of surgical intervention are visualized. In Fig. 3(c), the MEC is free of any MEE and biofilm. A portion of the TT (blue arrows, dashed) deeper inside the MEC is visualized. The TM (yellow line) appears thicker due to the presence of residual earwax (orange arrows, orange line) on the outer surface of the TM and because the image was acquired closer to the umbo, where the TM is naturally thicker.54 The surface image (inset) shows that some transparency has returned to the TM. Otoscopic metrics provide visual confirmation of surgical outcomes and, in this case, indicate a reduction in inflammation and a fluid-free middle-ear space compared to presurgery time points. The TT is observed in place and functionally venting the MEC.47,55 At the end of the records-based observation period, this subject did not report any symptoms of OM recurrence. When an infection occurred after postoperative follow-up or perhaps when surgery was ineffective at clearing infection-related components, additional biofilm- or MEE-related structures were observed affixed to the TM and/or within the MEC, respectively. Figure 4 highlights subject C5, who was presented with a history of recurrent episodes of acute OM that persisted after TT placement. Visible biofilm structures detected in OCT cross-sectional images persisted throughout all observation time points, including pre-TT placement [Figs. 4(a) and 4(b), green arrows] and post-TT placement [Fig. 4(c), green arrows]. Yellow and green bars indicate the location and thickness of the TM and biofilm, respectively. Longer-term follow-up was possible given a recurrence of the infection in this subject, who required additional outpatient visits. Approximately six months after the postoperative visit, a patchy or spatially inconsistent biofilm was observed affixed to the TM [Fig. 4(d)], while in some regions no biofilm was present [Fig. 4(e)]. The identification of both seemingly normal and pathological regions in these OCT images highlighted here was unexpected and found in only one ear from this one subject. However, this finding demonstrates the complex dynamics of biofilm formation in OM and regression after treatment, indicating that further investigation and longitudinal tracking at more time points may better capture these processes. The other ear of this subject and all other study subjects had consistent findings from each time point. No digital otoscopy image was available due to patient discomfort. An indisputable and unavoidable limitation in studies involving human subjects, especially those in active clinical and surgical settings, is the priority of patient needs and well-being over data collection, which in some cases presented a challenge for acquiring complete datasets. This subject was provided with antibiotics based on the physical exam and was scheduled for re-evaluation at a later date. Available data from the P dataset was typically limited to the first consultation visit and included OCT images, digital otoscopy images, and patient history. Imaging data from subsequent visits were not available and were lost to follow-up, a common problem in otolaryngology,52 as imaging subjects in this observational study were free to seek, reschedule, or not seek care as per their wishes. Almost all subjects in the P group had a reported history of recurrent OM (18/19, 95%) and mostly (17/19, 90%) were found with OCT to have biofilm-like structures affixed to the TM during the first visit, as noted in our previous studies. A total of 20 out of 25 subjects (80%) underwent TT surgery. However, 8 out of 25 (32%) subjects reported recurrence of infection during the postoperative observation period, which may have resulted from local recurrence of the original infection and biofilm or from a new, discrete OM infection. While TT surgery was performed depending on the clinical circumstances of each patient, it is notable that 3 out of 19 (16%) in our study had a history of multiple TT surgeries, with 2 of these subjects having biofilm-related structures present in OCT images. Additional figures are presented in the Appendix that demonstrates the diverse presentation of recurrent or chronic OM encountered in this study. 4.DiscussionAdditional infection-related structures were initially observed in OCT images from most subjects (92%, 23/25) diagnosed with recurrent or chronic OM and scheduled to undergo TT surgery, as per their standard-of-care. Through record-based follow-up of all subjects, surgical intervention was effective at clearing the infection and reducing or eliminating symptoms in 15 out of 20 subjects (75%) that received TT surgery. If observed with OCT, image analysis confirmed the absence of a middle-ear biofilm in these subjects. However, 5 out of 20 subjects (25%) that received surgery had persistent clinical symptoms of OM infection following TT surgery, and if observed with OCT, infection-related structures were present. These structures were similarly identified in subjects that had multiple surgical interventions and had returned for repeated treatments. Therefore, based on OCT imaging results, if a subject did not respond to surgical intervention, there was likely an insufficient clearance of infectious material from the MEC or a recurrence of the bacterial population and subsequent biofilm regrowth. A postsurgical OCT confirmation of the absence of a biofilm could then perhaps serve as a secondary diagnostic indicator or predictor for long-term success of the surgical intervention. A future study could similarly explore the effectiveness of pharmacological interventions to clear symptoms of OM in subjects identified with a middle-ear biofilm. Surgical intervention, in this case myringotomy and TT placement, results in both short- and long-term effects that influence several changes in an infected MEC. With myringotomy, a renewed immune and healing response is stimulated56 along with aspiration of the MEC and insertion of a TT. These interventions aid in clearing middle-ear fluid and provide a means of aerating the MEC. When considered in the context of biofilm-related infections, mechanical clearance and aspiration of the MEC disturb any biofilm and its growth environment both structurally and biochemically. Ototopical drops placed into the MEC also provide a higher and more effective concentration of antibiotics directly to the site of infection57,58 when compared to oral antibiotics.59 Successful clearance of the MEC and reduction of OM-related symptoms may indicate these structures are cleared by a combination of these factors. Regardless of any potential new diagnostic information gained with OCT, considering recurrent or chronic OM as a biofilm-mediated disease would also require investigating new or re-evaluating existing treatment options.60,61 Methods that attempt to noninvasively weaken, disrupt, or clear a biofilm62–64 could be employed before invasive means are considered or even employed in conjunction with surgical treatment for a more aggressive approach. However, if TT placement is found to be one of the most effective therapeutic interventions to treat biofilm-derived recurrent or chronic OM, then it will be necessary to weigh the related risks and outcomes associated with presumably more patients receiving tubes at a younger age. Serious consideration should be given to the fact that a majority of patients tend to outgrow complications and/or susceptibility to recurrent OM, perhaps due to improved function and increased diameter of the Eustachian tube with age65 or improved immune function with age.66 Conversely, it is also important to consider that many children are unnecessarily hearing impaired during this time, which delays learning and speech development at a crucial age in young subjects. Further investigation is undeniably necessary to observe broader subject population demographics, as well as biochemical and genetic factors, to more fully understand the dominant factors of middle-ear disease pathogenesis, as well as any physical or secondary indicators that can be used for diagnosis and monitoring. In this regard, tracking the reduction or clearance of biofilm biomass with OCT after surgical or pharmacological treatment may provide further insight into mechanisms for effective treatment of OM. To suggest any potential use of this OCT data for clinicians, further study is still needed and should include a randomized clinical trial with a larger subject population and a wider geographic and demographic distribution to capture a broader view of OM. With this longer-term study, diagnostic features in OCT images may be identified that predict a need for surgical intervention. This may allow for a quantitative and evidenced-based referral to surgery at earlier time points in the pathogenesis of chronic OM, potentially shortening the duration of disease symptoms and related morbidity prior to treatment and successful resolution. In this regard, OCT-based treatment guidelines for OM will need to be proposed, established, and evaluated, as was done for clinical cardiovascular67 OCT and clinical ophthalmic68 OCT clinical applications. There are several limitations in this initial observational study. With the spectral-domain OCT system used in these investigations, it was not technically possible to image deeper to the medial mucosal surfaces of the MEC. However, swept-source OCT systems can provide deeper imaging to over a centimeter,69 which can provide additional information on the location, extent, and severity of any middle-ear biofilm or MEE simultaneously on both the interior mucosal surface of the TM as well as the mucosal surface throughout the MEC. While the light reflex region of the TM was interrogated in this study and used as a consistent anatomical landmark for longitudinal image collection, the remaining areas of the TM may provide further information related to the biofilm or other middle-ear diseases. Techniques for rapidly generating three-dimensional images of the entire TM, while minimizing motion artifacts and coregistering these datasets among longitudinal visits are in development. The presence of specific otopathogens may ultimately govern whether surgery is effective.70 However, OCT is not sensitive to specific bacterial species. Ongoing research in our group is investigating the use of Raman spectroscopy for determining microbial content of the middle ear,71 which has previously been used to differentiate bacterial strains in culture.72 Finally, additional studies are needed to verify longer-term outcomes of study participants with OCT and the clinical relevance of the presence or absence of a middle-ear biofilm in patients with chronic OM. Another ongoing study is aimed at physically sampling, identifying, and verifying the infection-related structures and microbiological content that has been observed on the TM with OCT. Results will help to better understand and correlate the image-based findings with the presence of biofilms that were previously detected on middle-ear mucosa during chronic OM.26 5.ConclusionIn this study, a broad subject population was prospectively observed using OCT to assess the efficacy of surgical intervention to clear OM-related middle-ear fluid or biofilms and associated clinical symptoms. OCT image findings suggest that surgical intervention, consisting of myringotomy followed by TT placement, provides a means to clear the middle ear of infection-related biofilm structures and components. OCT shows promise to provide a clinically viable diagnostic and monitoring platform capable of providing physicians with new image-based information about the disease state of the middle ear. With further investigation, OCT image features may aid in the diagnosis and management of OM, especially when interpreted alongside physical exam, otoscopy findings, and patient history. AppendicesAppendixHere, additional data are presented that survey the wide range of clinical presentations of chronic or recurrent OM observed in this study. Figure 5 shows representative data from this group (subject P3). This subject presented with both moderate conductive hearing loss and an identified MEE in each ear. This subject was observed at both the first [Fig. 5(a)] and second [Fig. 5(b)] visits. Yellow and green bars indicate the location and thickness of the TM and biofilm, respectively. At both time points, additional infection-related structures were clearly visible within the MEC. This subject, like others in the P group, was noncompliant with scheduled follow-up exam times, and therefore, only information from the physical exam was available from the third visit. Figure 6 shows data from subject C4, diagnosed with persistent or frequent recurrent acute OM and ETD. Figure 6(a), acquired during the preoperative visit, shows an overall thickened structure comprised of the TM and attached biofilm. In this image, delineation of the TM from the biofilm can be challenging, likely because of refractive index matching occurring among these structures. Figure 6(b), acquired intraoperatively immediately prior to TT placement, shows that the biofilm is no longer present and was replaced by an MEE (white arrows). When imaged at the postsurgical follow-up visit [Fig. 6(c)], additional structures (green arrows) were found to be affixed to the TM. Although this subject had no reported symptoms of recurrent infection during the study period, the obstructed TT, as visualized in the inset digital otoscopy image, would have provided limited aeration and drainage of the MEC. This blockage likely prevented complete clearance of the middle-ear space. Figure 7 presents images from subject C6, who was originally presented with ETD and recurrent acute OM. When viewed at the postsurgical follow-up, the cross-sectional OCT images showed a TT within a cleared MEC. This again suggests that surgical intervention successfully clears the middle-ear space of biofilm-related structures. Another benefit of OCT is also indirectly highlighted in the digital otoscopy image of the TM. Most of the ear canal in this subject was occluded with cerumen, which makes any accurate observation or diagnosis using standard otoscopy prohibitive without first cleaning the ear canal to properly view the entire TM. However, the OCT beam only requires a small, clear direct line-of-sight imaging path and can propagate through small gaps in the cerumen within the tortuous ear canal. Subjects with repeated TT placement surgeries often present with different image-based TM features than those undergoing their first procedure. For instance, depending on the duration since the last TT surgery, thinning in the fibrous layer of the TM may be evident, or even a residual opening from an extruded TT may often still be visible in the TM. Figure 8 shows such a case from subject P14, who presented with persistent OME after a recent TT surgery. When examined, a residual perforation in the TM from a previous TT was visible in the otoscopy image. OCT of the TM showed a thinned, irregular TM and a thick, adherent, persistent biofilm (green arrows). DisclosuresAuthors S.A.B., R.L.S., R.M.N., and M.A.N. disclose a financial interest in PhotoniCare, Inc., which is commercializing OCT for imaging the ear. The other authors have no funding, financial relationships, or conflicts of interest to disclose. AcknowledgmentsThe authors would like to acknowledge the research staff at Carle Foundation Hospital, especially Deveine Toney, and the nursing staff at both the Carle Expanding Children’s Hearing Opportunities Center and the Carle Ambulatory Surgery Center, for their assistance during the examinations and surgeries. This work was funded by a National Institutes of Health Bioengineering Research Partnership (No. R01EB013723, S.A.B.). Additional information can be found at http://biophotonics.illinois.edu. ReferencesK. Ramakrishnan, R. Sparks and W. Berryhill,
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BiographyGuillermo L. Monroy is currently a graduate research fellow (PhD candidate) in the Biophotonics Imaging Laboratory, working under the guidance of Professor Stephen Boppart. He received his BS degree in computer engineering in 2011 and continued for his MS in bioengineering at the University of Illinois at Urbana-Champaign in 2013. His current academic interests include the integration of advanced biomedical instrumentation and imaging techniques to improve diagnosis and treatment in healthcare. Paritosh Pande received his BTech (hons) degree in electrical engineering and his MTech degree in instrumentation engineering, both from the Indian Institute of Technology, Kharagpur, India, in 2008, and his PhD in biomedical engineering from Texas A&M University, College Station, Texas, in 2014. His research interests include biomedical signal and image processing, pattern recognition, and the development of optical imaging technologies for biomedical diagnostics. Ryan M. Nolan received his MEng degree in biomedical engineering from Cornell University and then joined the Biophotonics Imaging Lab, the University of Illinois at Urbana-Champaign as an imaging research specialist. Currently, he is with PhotoniCare, a medical device company seeking to improve the diagnosis and management of middle-ear disease. Ryan L. Shelton received his PhD in biomedical engineering from Texas A&M University, followed by a postdoctoral fellowship at the University of Illinois at Urbana-Champaign. He has extensive experience in optical coherence tomography and photoacoustic imaging techniques. Currently, he is with PhotoniCare, a medical device company seeking to improve the diagnosis and management of middle-ear disease. Ryan G. Porter received his MD degree in 2005, continuing on to complete an internship in general surgery in 2006 and residency in Otolaryngology (H&NS) in 2010 at Loyola University, Chicago, Illinois. He completed a fellowship at the Michigan Ear Institute in Farmington Hills, Michigan, in 2012. Currently, he is at Carle Foundation Hospital in the Expanding Children’s Hearing Opportunities (ECHO) Otolaryngology Clinic. Michael A. Novak received his BS degree from The Ohio State University, Columbus, Ohio, in 1971, his MD degree from Baylor College of Medicine, Houston, Texas, in 1974, and completed residency in 1979. Currently, he is at Carle Foundation Hospital in the ECHO Otolaryngology Clinic. Darold R. Spillman Jr. received an associate of arts degree in human resources from the Community College of the Air Force, Maxwell AFB, Georgia, in 2005 and his BA degree in general studies from Eastern Illinois University, Charleston, Illinois, in 2015. He served in the United State Air Force from 1984 to 2007. He was a 1993 Presidential Point of Light Award nominee and was spotlighted in the Inside Illinois publication. Eric J. Chaney received his BS degree in biology from the University of Evansville in 1992. From 1993 to 1997, he was a research assistant at the Indiana University School of Medicine, Indiana State University. From 1997 to 2000, he was a transmission electron microscope technician at the University of Illinois at Urbana-Champaign. Since 2000, he has been a research scientist at the Biophotonics Imaging Laboratory, Beckman Institute for Advanced Science and Technology. Daniel T. McCormick received his BSE degree with distinction in biomedical engineering and electrical engineering from Duke University, Durham, North Carolina, in 1999 and his MS and PhD degrees in electrical and computer engineering from Cornell University, Ithaca, New York, in 2002 and 2003, respectively. He founded Advanced MEMS in 2005 to focus on the development and commercialization of MEMS systems for biophotonic and biomedical applications, with systems employed in numerous human research trials and observational studies. Stephen A. Boppart received his PhD in electrical and medical engineering from MIT in 1998, and his MD from Harvard Medical School in 2000. He is an Abel Bliss professor of engineering, a head of the Biophotonics Imaging Laboratory, and a director of the Center for Optical Molecular Imaging. His interests include the development and translation of optical imaging technologies for biological and medical applications. He is a fellow of SPIE, AAAS, IEEE, OSA, BMES, and AIMBE. |