3D printed temporal bones for preoperative simulation and planning.

OBJECTIVE: Demonstrate the utility of 3D printed temporal bone models in individual patient preoperative planning and simulation. METHODS: 3D models of the temporal bone were made from 5 pediatric and adult patients at a tertiary academic hospital with challenging surgical anatomy planned for cochlear implantation or exteriorization of cholesteatoma with complex labyrinthine fistula. The 3D models were created from CT scan used for preoperative planning, simulation and intraoperative reference. The utility of models was assessed for ease of segmentation and production and impact on surgery in regard to reducing intraoperative time and costs, improving safety and efficacy. RESULTS: Three patients received cochlear implants, two exteriorization of advanced cholesteatoma with fistulas (1 internal auditory canal/cochlea, 1 all three semicircular canals). Surgical planning and intraoperative referencing to the simulations by the attending surgeon and trainees significantly altered original surgical plans. In a case of X-linked hereditary deafness, optimal angles and rotation maneuvers for cochlear implant insertion reduced operating time by 93 min compared to the previous contralateral side surgery. Two cochlear implant cases planned for subtotal petrosectomy approach due to aberrant anatomy were successfully approached through routine mastoidectomy. The cholesteatoma cases were successfully exteriorized without necessitating partial labyrinthectomy or labyrinthine injury. There were no complications. CONCLUSION: 3D printed models for simulation training, surgical planning and use intraoperatively in temporal bone surgery demonstrated significant benefits in designing approaches, development of patient-specific techniques, avoidance of potential or actual complications encountered in previous or current surgery, and reduced surgical time and costs.

Balloon dilation improves both the hearing level and the quality of life in patients suffering from obstructive Eustachian tube dysfunction.

PURPOSE: Chronic obstructive Eustachian tube dysfunction (OETD) can lead to tympanic membrane (TM) retraction and middle ear effusion (MEE) which can cause conductive hearing impairment, which among other ear symptoms can lower the quality of life (QoL). In this prospective study we assess hearing results and subjective changes in QoL following balloon Eustachian tuboplasty (BET) in treatment of OETD. METHODS: Totally 25 ears with TM retraction and 18 ears with MEE due to chronic OETD underwent BET as the sole intervention. Outcomes including otoscopy, ability to perform the Valsalva maneuver, tympanometry, audiometry, Eustachian tube inflammation scale and the Glasgow Benefit Inventory questionnaire (GBI) were obtained on all patients preoperatively and 6 months postoperatively. RESULTS: Hearing thresholds improved statistically significantly (p < 0.05) with means of 3 dB in the TM retraction group and 9 dB in the MEE group. Total GBI results indicated a positive influence on patients' QoL. Valsalva success rate was 80% in patients with TM retraction and 67% in patients with MEE. Tympanometry results improved in 50% of TM retraction patients and in 33% of MEE patients. CONCLUSIONS: Here we demonstrated that the BET has a positive impact on patients' conductive hearing loss and QoL in patients with TM retraction or MEE. Results were better in TM retraction group than in MEE group.

Vestibular Preservation in Pediatric Cochlear Implantation.

OBJECTIVES: Evaluate the rate of preserved vestibular function in pediatric cochlear implant surgery. STUDY DESIGN: Retrospective case review. METHODS: Pre- and post-operative vestibular tests were compared in children who underwent cochlear implantation at a tertiary level pediatric hospital over a 4-year period. RESULTS: Data from 59 implanted ears in 44 children was included. Median age was 2.8 years at initial testing (range 7 months - 21 years) with 1:1 male/female ratio. Implant surgeries were 26 unilateral, 13 bilateral simultaneous, and 5 bilateral sequential. The majority were implanted with slim, non-styletted electrodes (86.4%) via a round window approach (91.5%). Normal pre-operative results were preserved post-operatively on rotary chair testing in 75% (21/28) of patients, cervical vestibular evoked myogenic potential testing in (75%) 30/40 of ears tested, ocular vestibular evoked myogenic potential testing in 85.7% (6/7) of ears tested, video head impulse testing in 100% (9/9) of ears tested, and computerized dynamic posturography in 100% (5/5) of patients tested. Overall, 62.5% of patients had no new deficits on any vestibular test performed post-operatively. CONCLUSIONS: Preservation rates of vestibular function following cochlear implant surgery were higher in this cohort than what has been reported in many earlier studies. Contemporary, less traumatic electrodes and insertion techniques may be a significant factor. The risk of causing a new, severe bilateral vestibular loss with long-term functional impacts appears to be low. Further study is warranted on the impacts of different cochlear implant electrode designs and insertion approaches on post-operative vestibular preservation. LEVEL OF EVIDENCE: 4, Case Series Laryngoscope, 134:1913-1918, 2024.

Long-term efficacy of balloon dilation of the pediatric Eustachian tube: A six-year matched cohort study.

PURPOSE: Balloon dilation of the Eustachian tube (BDET) has not been evaluated extensively in children outside of retrospective case series. The purpose of this study is to report the long-term safety and efficacy of this procedure in children with matched controls. MATERIALS AND METHODS: This is a two-center retrospective matched cohort study. Children having undergone tympanostomy tube (TT) placement and adenoidectomy with recurrence of symptoms underwent BDET at an academic affiliated multi-specialty practice. Comparison was made with children receiving TT at a tertiary medical center, matching for number of prior TT, prior adenoidectomy, age, and sex. Outcome measures were risk of failure and the need for additional surgery. Kaplan-Meier survival plots were used to compare risk of failure. RESULTS: Thirty-three Eustachian tubes were dilated in 20 patients, aged 14 months-14 years. All patients had previously undergone TT insertion and adenoidectomy. Patients undergoing BDET had normal post-operative tympanograms in 80 % of cases. Mean follow up was 6.7 years with 2 patients failing in the BDET group and 8 in the TT insertion group. Dilated patients had a significantly lower risk of failure than those who underwent TT insertion (adjusted HR: 0.18; 95 % CI: 0.04, 0.81; p = 0.03). The probability of being failure free at six years was 88 % (95 % CI: 71, 95 %) in the BDET cohort and 53 % (95 % CI: 33, 70 %) in the TT insertion cohort. There were no complications. CONCLUSIONS: BDET appears to be safe and possibly superior to TT placement in children with refractory Eustachian tube dysfunction. LEVEL OF EVIDENCE: 2b.

Patulous Eustachian Tube Dysfunction Symptoms Following Balloon Dilation.

OBJECTIVE: Clinicians increasingly perform balloon dilation of the Eustachian tube (BDET) to treat obstructive Eustachian tube dysfunction (OETD) refractory to medical management. Reported complications have been limited and include patulous Eustachian tube dysfunction (PETD). This multicenter study investigates the incidence of PETD and associated factors. METHODS: Consecutive patients at three academic centers undergoing BDET (January 2014-November 2019) for OETD refractory to medical therapy were included. PETD was diagnosed by patient-reported symptoms of autophony of voice and/or breathing. Associated factors studied include age, sex, comorbidities, balloon size, duration of inflation, repeat BDET, and adjunctive procedures. RESULTS: BDET procedures (n = 295 Eustachian tubes) were performed on 182 patients. Mean age was 38.4 years (SD 21.0; range 7-78) and 41.2% were female. Twenty cases of PETD (6.8% of procedures; 9.3% of patients) occurred following BDET. Risk of PETD did not vary by institution, comorbidities, or adjunctive procedure. Age ≤18 years (adjusted risk ratio [RR] = 3.26; 95% confidence interval [CI]: 1.24, 8.54; p = 0.02), repeat BDET (RR = 3.26; 95% CI: 2.15, 4.96; p < 0.001), and severe preoperative Eustachian tube inflammation (RR = 2.83; 95% CI: 1.10, 7.28; p = 0.03) were associated with increased risk of developing PETD in the multivariable model. Most symptoms were reported as mild or intermittent. CONCLUSION: BDET caused PETD symptoms in approximately 7% of dilated Eustachian tubes in this study with increased risk for younger patients and those with severe inflammation or undergoing repeat dilations. Although most cases were self-limited, symptoms can persist. Awareness of risk factors may aid clinicians in limiting this complication. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:3152-3157, 2023.

Measurements of The Pediatric Cartilaginous Eustachian Tube: Implications for Balloon Dilation.

OBJECTIVES: (1) Measure the cartilaginous Eustachian tube (ET) length using a computed tomography (CT) scan and (2) develop a prediction model to measure this length without the need of a CT scan. STUDY DESIGN: CT measurements in children. SETTING: Children's Hospital. METHODS: CT scans were reformatted to project the cranial and caudal limits of the cartilaginous ET. The length was measured in 193 children who underwent a neck CT scan for nonotologic indications. Five physicians independently reviewed all or some of these measures. Four different models based on age, age ranges, weight, and height were created and compared to predict ET length. RESULTS: The cartilaginous ET length was 25.3 ± 3.1 mm for the right and for the left ear. The mean ET length for the females was statistically significantly less than the length in males. The lower ET lengths in children as old as 5 years of age were less than the 2 cm adult criteria used for catheter insertion. All 4 models performed equally well in predicting ET length. Model number 4, which is based on height, was the easiest to calculate ET length. CONCLUSION: The cartilaginous portion of the pediatric ET can be measured with good precision using reformatted CT images. We caution against using the "adult" criteria of 2 cm for catheter insertion in children, especially those younger than 5 years of age. We recommend using a model utilizing height measures to estimate ET length or direct measurements from a reformatted CT scan. LEVEL OF EVIDENCE: NA Laryngoscope, 133:396-402, 2023.

Reconstruction of the Obliterated Eustachian Tube: A Pilot Case Series.

OBJECTIVE: To investigate the safety and early efficacy of a procedure for reconstruction of the obliterated Eustachian tube (ET). STUDY DESIGN: Retrospective case series. METHODS: Patients with total obliteration of the cartilaginous ET, with intractable mucoid effusion causing repeated occlusion of tympanostomy tubes were included. Patients underwent endoscopic transnasal/transoral reconstruction of the obliterated ET using transtympanic illuminated guidewire guidance. A temporary stent (angiocatheter filled with bonewax) was placed to maintain patency while healing. In four cases an additional steroid-eluting propel stent was placed in the ET orifice. Main outcome measures were otomicroscopy results, absence of middle ear effusion, and nasopharyngoscopy showing patency of the ET orifice. RESULTS: Nine ETs (seven patients), ages 17-68 years (mean 37.9) underwent ET reconstruction. Follow-up ranged from 4 to 56 months (mean 30.9 months). 89% of operated ears had no effusion at last follow-up. Two patients (three Eustachian tubes) underwent successful reoperation. There were no complications directly related to the procedure. Etiologies of obliteration included scarring after sinus surgery, obstruction after maxillo-mandibular advancement surgery (two patients), bullous pemphigus, gunshot trauma, and previous patulous obliteration (two patients). CONCLUSIONS: Complete occlusion of the cartilaginous ET can be associated with intractable mucoid effusion; endoscopic examination should be considered in such cases. In this pilot study, ET reconstruction was found to be a safe and possibly effective procedure in patients with total obliteration of the ET from various etiologies. Larger studies with long term follow up are indicated. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:1970-1975, 2023.

Surfactant proteins and innate immunity of otitis media.

Otitis media (OM) is the most common disease among young children and one of the most frequent reasons to visit the pediatrician. Development of OM requires nasopharyngeal colonization by a pathogen which must gain access to the tympanic cavity through the eustachian tube (ET) along with being able to overcome the defense mechanisms of the immune system and middle ear mucosa. OM can be caused by viral or bacterial infection. The three main bacterial pathogens are Streptococcus pneumoniae, nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis. Innate immunity is important in OM resolution as the disease occurs in very young children before the development of specific immunity. Elements of innate immunity include natural barriers and pattern recognition receptors such as Toll like receptors (TLRs), and Nod like receptors (NLRs). Surfactant proteins A (SP-A) and D (SP-D) act as pattern recognition receptors and are found in the lung and many other tissues including the ET and the middle ear where they probably function in host defense. Surfactant has a potential for use in the treatment of OM due to surface tension lowering function in the ET, and the possible immune functions of SP-D and SP-A in the middle ear and ET.

Comparison of outcomes for balloon dilation of the Eustachian tube under local vs general anesthesia.

Objective: To compare the effectiveness of balloon dilation of the Eustachian tube (BDET) under local versus general anesthesia in the treatment of obstructive Eustachian tube dysfunction (OETD). Study Design: Retrospective review. Methods: Consecutive patients ages ≥18 with persistent OETD having failed adequate medical therapy underwent BDET between 2013 and 2018 under local or general anesthesia. Inclusion criteria were persistent type B or C tympanograms with symptoms or type A with symptoms upon barochallenge. Objective outcome measures were tympanometry, otoscopy and the need for additional subsequent intervention (revision dilation and tympanostomy tube). Primary outcome (failure) was defined as no change or worse in tympanogram. Results: The 191 patients (332 ETs), ages 18-88 years (mean 58.0) underwent BDET. The 112 patients (59%) were female. The 107 procedures (32%) were performed under local anesthesia. Mean duration of follow-up was 3.1 years (SD 1.9). Tympanograms improved to type A in 88% for BDET under local and 74% for general anesthesia at 12 months. Probability of being failure-free at 5 years was 70% (95% confidence interval [CI]: 52%-82%) in the local anesthesia group versus 65% (95% CI: 55%-73%) in the general anesthesia group. Risk of failure did not significantly differ between the groups (HR = 0.60; 95% CI: 0.27-1.31; p = .20). Conclusion: BDET under local anesthesia is effective in treating OETD and results in sustained improvements over 2 years. The procedure was successfully performed in all but one case utilizing a precise anesthesia protocol, and results are comparable with the procedure performed under general anesthesia. Level of evidence: 4.

Efficacy of Balloon Tuboplasty for Baro-Challenge-Induced Eustachian Tube Dysfunction: A Systematic Review and a Retrospective Cohort Study of 39 Patients.

OBJECTIVE: Baro-challenge-induced Eustachian tube dysfunction (ETD) manifests due to inadequate Eustachian tube (ET) function during rapid ambient pressure changes, although ET function may be normal in normobaric situations. This systematic review and retrospective cohort study aimed to evaluate the effectiveness of balloon Eustachian tuboplasty (BET) for the treatment of baro-challenge-induced ETD. DATA SOURCES: PubMed, the Cochrane Library, Scopus, and Helsinki University Hospital cohort. METHODS: A systematic literature search was conducted in November 2020 and resulted in 174 articles. Eight articles fulfilled the inclusion criteria. Data was available altogether from 74 adult baro-challenge-induced ETD patients. In addition, we retrospectively evaluated 39 BET operations at Helsinki University Hospital from 2011 to 2020. Data from these 39 patients were collected from medical charts, and a questionnaire was sent to the patients. Meta-analysis was used to evaluate subjective symptom improvement, changes in ETD Questionnaire-7 (ETDQ-7) scores, and Valsalva maneuver performance. RESULTS: In the systematic review, the outcome parameters varied between studies. Improvement was reported in subjective symptoms, Valsalva maneuver, ETDQ-7, tubomanometry, and pressure chamber test. Response rate for the Helsinki University Hospital cohort study was 72% (28/39). Mean follow-up time from the BET to the questionnaire was 4 years 8 months (SD 26months). Of those patients 93% (26/28) found the operation beneficial. Meta-analysis including up to 113 patients showed improvement in Valsalva maneuver, ETDQ-7, and improvement in subjective symptoms. Overall improvement in symptoms was noted in 81% of the patients. CONCLUSION: BET seems to be effective in the majority of patients with baro-challenge-induced ETD.

Pain at the Cochlear Implant Site Requiring Device Removal in Pediatric Patients.

OBJECTIVES: Idiopathic pain at the cochlear implant (CI) site outside of the immediate postoperative period is an uncommon occurrence but may necessitate device explantation. Our objective was to describe the clinical course for pediatric patients with CI site pain who ultimately required device explantation. STUDY DESIGN: Retrospective chart review. METHODS: We performed a retrospective database review of CIs performed at a tertiary referral center for pediatric cochlear implantation. We specifically evaluated pediatric patients who presented with pain at or near the CI device site and ultimately required explantation. RESULTS: Fifteen patients (16 CIs) had pain at or near the CI site requiring device explantation. Cultures taken during site exploration or device explantation identified bacteria in 86% and 81% of procedures, respectively. Propionibacterium acnes and Staphylococcus non-aureus were the most commonly identified organisms. CONCLUSIONS: The majority of patients with idiopathic pain in this cohort ultimately requiring CI explantation had chronic bacterial colonization. LEVEL OF EVIDENCE: 4 (Case series) Laryngoscope, 132:2044-2049, 2022.

Peripheral Vestibular Dysfunction Is a Common Occurrence in Children With Non-syndromic and Syndromic Genetic Hearing Loss.

Hearing loss (HL) is the most common sensory deficit in humans and is frequently accompanied by peripheral vestibular loss (PVL). While often overlooked, PVL is an important sensory dysfunction that may impair development of motor milestones in children and can have a significant negative impact on quality of life. In addition, many animal and in vitro models of deafness use vestibular hair cells as a proxy to study cochlear hair cells. The extent of vestibular end organ dysfunction associated with genetic pediatric hearing loss is not well-understood. We studied children with a known genetic cause of hearing loss who underwent routine preoperative vestibular testing prior to cochlear implantation between June 2014 and July 2020. Vestibular testing included videonystagmography, rotary chair, video head impulse testing, and/or vestibular evoked myogenic potentials. Etiology of HL was determined through history, physical examination, imaging, laboratory testing, and/or genetic testing. Forty-four children (21 female/23 male) met inclusion criteria; 24 had genetic non-syndromic and 20 had genetic syndromic forms of HL. Mean age at the time of testing was 2.8 ± 3.8 years (range 7 months-17 years). The most common cause of non-syndromic HL was due to mutations in GJB2 (n = 13) followed by MYO15A (3), MYO6 (2), POU3F4 (2), TMPRSS3 (1), CDH23 (1), TMC1 (1), and ESRRB (1). The most common forms of syndromic HL were Usher syndrome (4) and Waardenburg (4), followed by SCID/reticular dysgenesis (3), CHARGE (2), CAPOS (1), Coffin-Siris (1), Jervell and Lange-Nielsen (1), Noonan (1), peroxisome biogenesis disorder (1), Perrault (1), and Trisomy 21 (1). Overall, 23 patients (52%) had PVL. A larger proportion of children with syndromic forms of HL had PVL (12/20, 60%) compared with children with genetic non-syndromic HL (11/24, 46%), though without statistical significant (p = 0.3). The occurrence of PVL varied by affected gene. In conclusion, PVL is a common finding in children with syndromic and non-syndromic genetic HL undergoing vestibular evaluation prior to cochlear implantation. Improved understanding of the molecular physiology of vestibular hair cell dysfunction is important for clinical care as well as research involving vestibular hair cells in model organisms and in vitro models.

Further Research Needed to Understand Relationship Between Tubarial Glands and Eustachian Tube Dysfunction.

The pathophysiology of eustachian tube dysfunction (ETD) remains poorly characterized, and it may result in significant patient morbidity. A recent study has identified a collection of previously unidentified salivary glands in the nasopharynx that overlay the torus tubarius. While salivary gland tissue has been described in the nasopharynx, the newly discovered salivary gland tissue has been denoted tubarial glands (TGs) and theorized to be a distinct organ. The TGs have been suggested to aid in lubrication of the oropharynx and nasopharynx. However, the exact clinical significance of TGs is unknown. Given the proximity of the TG to the eustachian tube, it is possible that the TGs may be related to the development of ETD. Future studies of the TGs and related pathophysiology may improve approaches to developing future ETD treatments.

Intradermal Testing Doubles Identification of Allergy among 110 Immunotherapy-Responsive Patients with Eustachian Tube Dysfunction.

The purpose of this study was to determine whether the sensitivity advantage of intradermal dilutional testing (IDT) is clinically relevant in patients with obstructive Eustachian tube dysfunction (ETD) or otitis media with effusion (OME). This retrospective, private-practice cohort study compared the sensitivity of skin prick tests (SPT) vs. IDT in 110 adults and children with suspected allergy and OME. Primary outcome measure was symptom resolution from allergy immunotherapy (AIT). IDT identified 57% more patients as being allergic, and 8.6 times more reactive allergens than would have been diagnosed using only SPT. Patients diagnosed by IDT had the same degree of symptom improvement from immunotherapy, independent of allergen sensitivity (66% by SPT vs. 63% by IDT; p = 0.69, not different). Low-sensitivity allergy tests, which may fail to identify allergy in over two thirds of children aged 3 to 15 as being atopic, or among 60% of patients with ETD, may explain why many physicians do not consider allergy as a treatable etiology for their patient's OME/ETD. IDT offers superior sensitivity over SPT for detecting allergens clinically relevant to treating OME/ETD. These data strongly support increased utilization of intradermal testing and invite additional clinical outcome studies.

Facial Paralysis From Post-transplant Lymphoproliferative Disorder.

OBJECTIVE: We report a case of facial paresis and profound hearing loss from post-transplant lymphoproliferative disorder (PTLD) in a pediatric patient with neuroblastoma. PATIENT: Three-year-old boy with rapidly progressive right facial paresis and sensorineural hearing loss. High-risk neuroblastoma had been diagnosed 1 year earlier, treated with chemotherapy and resection of the adrenal primary tumor. Two months after two autologous hematopoietic stem cell transplantations (HSCT), the patient developed facial paralysis. Magnetic resonance imaging (MRI) showed bilateral progressive internal auditory canal (IAC) enhancing lesions with a mass lesion on the right and wispy enhancement on the left and enhancement within the right cochlea. Lumbar puncture (LP) was positive for Epstein-Barr virus (EBV) making the diagnosis of PTLD most probable. Biopsy of the right IAC lesion was deferred because of potential procedural risks including intradural spread of tumor or fungus. The patient was treated with anti-fungal therapy and systemic rituximab without improvement. Subsequent intrathecal rituximab resulted in improvement of lesions on MRI and clearance of EBV from the cerebrospinal fluid (CSF). INTERVENTIONS: Mastoidectomy for biopsies from the mastoid and middle ear. Intrathecal treatment with rituximab. MAIN OUTCOME MEASURES: Imaging assessment of IAC lesion, CSF EBV titers, facial nerve function. RESULTS: Gradual resolution of IAC mass lesions, remission of PTLD, and facial improvement from House-Brackmann score of 4 to 3. CONCLUSIONS: PTLD causing facial paresis after autologous HSCT has not been previously reported and may be considered in the differential diagnosis of lesions causing facial paresis in patients who have received a stem cell or solid organ transplant.

Balloon Dilation for Obstructive Eustachian Tube Dysfunction in Children.

OBJECTIVE: Determine the safety and efficacy of balloon dilation of the Eustachian tube (ET) in pediatric patients. STUDY DESIGN: Retrospective matched cohort study. SETTING: Tertiary medical center. PATIENTS: Pediatric patients (<18 yr) with persistent (>1.5 yr) chronic Eustachian tube dysfunction (ETD) with previous tympanostomy tube (TT) insertion versus matched controls. INTERVENTIONS: Balloon dilation of the cartilaginous ET (BDET) was performed using concomitant myringotomy with/without tube placement and adjunctive procedures if indicated versus controls (TT). MAIN OUTCOME MEASURES: Otitis media with effusion (OME)/retraction with need for additional tube, tympanogram, audiogram, otomicroscopy, ET mucosal inflammation/opening score, and Valsalva maneuver. RESULTS: Forty six ETs (26 patients), ages 7 to 17 years (mean 12.5) underwent BDET. Mean follow-up was 2.3 years (standard deviation [SD], 1.1; range, 6 mo-5 yr). Significant improvements were observed for all measures. Tympanic membranes were healthy in 9% preoperatively, 38% at 6 months, 55% at 12 months, and 93% at 36 months postoperatively. Tympanograms improved to type A in 50% at 6 months, 59% at 12 months, and 85% at 36 months. Mean scores of mucosal inflammation declined from 3.2 (±0.6) preoperatively to 2.5 (±0.7) at 6 months and 1.7 (±0.6) at 36 months postoperatively. BDET had lower risk of failure versus TT insertion (adjusted hazard ratio [HR] 0.26; 95% confidence interval [CI]: 0.10, 0.70; p = 0.007). Probability of being failure free at 2 years was 87% (95% CI: 70, 94%) after BDET and 56% (95% CI: 40, 70%) after TT insertions. CONCLUSIONS: BDET is a safe and possibly effective procedure in selected pediatric patients with chronic ETD.

Assessment of PIV performance in validating CFD models from nasal cavity CBCT scans.

OBJECTIVE: The aim of our study was to investigate how well Particle Image Velocimetry (PIV) measurements could serve Computational Fluid Dynamics (CFD) model validation for nasal airflow. MATERIAL AND METHODS: For the PIV measurements, a silicone model of the nose based on cone beam computed tomography (CBCT) scans of a patient was made. Corresponding CFD calculations were conducted with laminar and two turbulent models (k-ω and k-ω SST). RESULTS: CFD and PIV results corresponded well in our study. Especially, the correspondence of CFD calculations between the laminar and turbulent models was found to be even stronger. When comparing CFD with PIV, we found that the results were most convergent in the wider parts of the nasal cavities. CONCLUSION: PIV measurements in realistically modelled nasal cavities succeed acceptably and CFD calculations produce corresponding results with PIV measurements. Greater model scaling is, however, necessary for better validations with PIV and comparisons of competing CFD models.

Three-Dimensional Printing of the Nasal Cavities for Clinical Experiments.

3D printing has produced many beneficial applications for surgery. The technique´s applicability in replicating nasal cavity anatomy for clinical use has not been studied. Our aim was to determine whether 3D printing could realistically replicate the nasal cavities and the airflow passing through them from a clinical point of view. We included Cone Beam Computed Tomography (CBCT) scans of five patients with symptoms of chronic nasal congestion. These CBCT scans were used to print plastic 3D prints of the nasal cavities, which were also CBCT scanned and the measurements were compared. The results in vivo were higher than the results in vitro in maxillary sinus volumes with a ratio of 1.05 ± 0.01 (mean ± SD) and in the nasal cavities with a ratio of 1.20 ± 0.1 (mean ± SD). Linear measurements in vitro were very close to those in vivo. Rhinomanometric results showed some differences, but rhinomanometric graphs in vitro were close to the graphs in vivo. 3D printing proved to be a suitable and fast method for replicating nasal cavity structures and for the experimental testing of nasal function. It can be used as a complementary examination tool for rhinomanometry.

International Pediatric Otolaryngology Group (IPOG) Consensus Recommendations: Congenital Cholesteatoma.

OBJECTIVE: To provide recommendations to otolaryngologists and allied physicians for the comprehensive management of children who present with signs and symptoms of congenital cholesteatoma. METHODS: A two-iterative Delphi method questionnaire was used to establish expert recommendations by the members of the International Pediatric Otolaryngology Group, on the preoperative work-up, the perioperative considerations, and follow-up. RESULTS: Twenty-two members completed the survey, in 14 tertiary-care center departments representing 5 countries. The main consensual recommendations were: a precise otoscopic description of the quadrants involved, extensive audiological workup (bilateral tonal, vocal audiometry, and BERA), and a CT scan are required. Facial nerve monitoring and a combination of microscope and telescope are recommended for surgical removal. Clinical and audiological follow-up should be pursued yearly for at least 5 years. First MRI follow-up should be done at 18 months postoperatively if the removal violated the matrix. MRI follow-up duration depends on the initial extent of the cholesteatoma. CONCLUSION: The goal of preoperative and follow-up consensus from International Pediatric Otolaryngology Group participants is to help manage infants and children with congenital cholesteatoma. The operative techniques may vary, and experienced surgeons must perform these procedures.