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Studying the impact of antibiotic treatment on otitis media (OM), the leading cause of primary care office visits during childhood, is critical to develop appropriate treatment strategies. Tracking dynamic middle ear conditions during antibiotic treatment is not readily applicable in patients, due to the limited diagnostic techniques available to detect the smaller amount and variation of middle ear effusion (MEE) and middle ear bacterial biofilm, responsible for chronic and recurrent OM. To overcome these challenges, a handheld optical coherence tomography (OCT) system has been developed to monitor in vivo response of biofilms and MEEs in the OM-induced chinchilla model, the standard model for human OM. As a result, the formation of MEE as well as biofilm adherent to the tympanic membrane (TM) was longitudinally assessed as OM developed. Various types of MEEs and biofilms in the chinchilla model were identified, which showed comparable features as those in humans. Furthermore, the effect of antibiotics on the biofilm as well as the amount and type of MEEs was investigated with low-dose and high-dose treatment (ceftriaxone). The capability of OCT to non-invasively track and examine middle ear conditions is highly beneficial for therapeutic OM studies and will lead to improved management of OM in patients.

A middle ear infection is a prevalent inflammatory disease most common in the pediatric population, and its financial burden remains substantial. Current diagnostic methods are highly subjective, relying on visual cues gathered by an otoscope. To address this shortcoming, optical coherence tomography (OCT) has been integrated into a handheld imaging probe. This system can non-invasively and quantitatively assess middle ear effusions and identify the presence of bacterial biofilms in the middle ear cavity during ear infections. Furthermore, the complete OCT system is housed in a standard briefcase to maximize its portability as a diagnostic device. Nonetheless, interpreting OCT images of the middle ear more often requires expertise in OCT as well as middle ear infections, making it difficult for an untrained user to operate the system as an accurate stand-alone diagnostic tool in clinical settings. Here, we present a briefcase OCT system implemented with a real-time machine learning platform for middle ear infections. A random forest-based classifier can categorize images based on the presence of middle ear effusions and biofilms. This study demonstrates that our briefcase OCT system coupled with machine learning can provide user-invariant classification results of middle ear conditions, which may greatly improve the utility of this technology for the diagnosis and management of middle ear infections.

To non-invasively assess the impact of antibiotic therapy on otitis media (OM), a handheld OCT system was developed to longitudinally monitor in vivo middle ear conditions of OM-induced chinchilla models. The formation of middle ear effusions (MEEs) and biofilm were examined over the course of the infection. Furthermore, the effect of antibiotics on the biofilm as well as the amount and type of MEEs was investigated with low-dose and high-dose antibiotics (ceftriaxone). Quantitative parameters, such as TM thickness and effusion and biofilm scattering/texture, were correlated with histology and fluorescence in situ hybridization (FISH) at the end time point.

Otitis media (OM) is an extremely common disease that affects children worldwide. Optical coherence tomography (OCT) has emerged as a noninvasive diagnostic tool for OM, which can detect the presence and quantify the properties of middle ear fluid and biofilms. Here, the use of OCT data from the chinchilla, the gold-standard OM model for the human disease, is used to supplement a human image database to produce diagnostically relevant conclusions in a machine learning model. Statistical analysis shows the datatypes are compatible, with a blended-species model reaching ∼95% accuracy and F1 score, maintaining performance while additional human data is collected.

Decreased mobility of the human eardrum, the tympanic membrane (TM), is an essential indicator of a prevalent middle ear infection. The current diagnostic method to assess TM mobility is via pneumatic otoscopy, which provides subjective and qualitative information of subtle motion. In this study, a handheld spectral-domain pneumatic optical coherence tomography system was developed to simultaneously measure the displacement of the TM, air pressure inputs applied to a sealed ear canal, and to perform digital pneumatic otoscopy. A novel approach based on quantitative parameters is presented to characterize spatial and temporal variations of the dynamic TM motion. Furthermore, the TM motions of normal middle ears are compared with those of ears with middle ear infections. The capability of non-invasively measuring the rapid motion of the TM is beneficial to understand the complex dynamics of the human TM, and can ultimately lead to improved diagnosis and management of middle ear infections.

OBJECTIVE: To characterize otitis media–associated structures affixed to the mucosal surface of the tympanic membrane (TM) in vivo and in surgically recovered in vitro samples. STUDY DESIGN: Prospective case series without comparison. SETTING: Outpatient surgical care center. SUBJECTS AND METHODS: Forty pediatric subjects scheduled for tympanostomy tube placement surgery were imaged intraoperatively under general anesthesia. Postmyringotomy, a portable optical coherence tomography (OCT) imaging system assessed for the presence of any biofilm affixed to the mucosal surface of the TM. Samples of suspected microbial infection–related structures were collected through the myringotomy incision. The sampled site was subsequently reimaged with OCT to confirm collection from the original image site on the TM. In vitro analysis based on confocal laser scanning microscope (CLSM) images of fluorescence in situ hybridization–tagged samples and polymerase chain reaction (PCR) provided microbiological characterization and verification of biofilm activity. RESULTS: OCT imaging was achieved for 38 of 40 subjects (95%). Images from 38 of 38 (100%) of subjects observed with OCT showed the presence of additional microbial infection–related structures. Thirty-four samples were collected from these 38 subjects. CLSM images provided evidence of clustered bacteria in 32 of 33 (97%) of samples. PCR detected the presence of active bacterial DNA signatures in 20 of 31 (65%) of samples. CONCLUSION: PCR and CLSM analysis of fluorescence in situ hybridization–stained samples validates the presence of active bacteria that have formed into a middle ear biofilm that extends across the mucosal layer of the TM. OCT can rapidly and noninvasively identify middle ear biofilms in subjects with severe and persistent cases of otitis media.

Objectives: Wideband acoustic immittance (WAI) noninvasively assesses middle ear function by measuring the sound conduction over a range of audible frequencies. Although several studies have shown the potential of WAI for detecting the presence of middle ear effusions (MEEs), determining the effects of MEE type and amount on WAI in vivo has been challenging due to the anatomical location of middle ear cavity. The purpose of this study is to correlate WAI measurements with physical characteristics of the middle ear and MEEs determined by optical coherence tomography (OCT), a noninvasive optical imaging technique. Design: Sixteen pediatric subjects (average age of 7 ± 4 years) were recruited from the primary care clinic at Carle Foundation Hospital (Urbana, IL). A total of 22 ears (normal: 15 ears, otitis media with effusion: 6 ears, and acute otitis media: 1 ear, based on physician’s diagnosis) were examined via standard otoscopy, tympanometry, OCT imaging, and WAI measurements in a busy, community-based clinical setting. Cross-sectional OCT images were analyzed to quantitatively assess the presence, type (relative turbidity based on the amount of scattering), and amount (relative fluid level) of MEEs. These OCT metrics were utilized to categorize subject ears into no MEE (control), biofilm without a MEE, serous-scant, serous-severe, mucoid-scant, and mucoid-severe MEE groups. The absorbance levels in each group were statistically evaluated at α = 0.05. Results: The absorbance of the control group showed a similar trend when compared with a pediatric normative dataset, and the presence of an MEE generally decreased the power absorbance. The mucoid MEE group showed significantly less power absorbance from 2.74 to 4.73 kHz (p < 0.05) when compared with the serous MEE group, possibly due to the greater mass impeding the middle ear system. Similarly, the greater amount of middle ear fluid contributed to the lower power absorbance from 1.92 to 2.37 kHz (p< 0.05), when compared with smaller amounts of fluid. As expected, the MEEs with scant fluid only significantly affected the power absorbance at frequencies greater than 4.85 kHz. A large variance in the power absorbance was observed between 2 and 5 kHz, suggesting the dependence on both the type and amount of MEE. Conclusions: Physical characteristics of the middle ear and MEEs quantified from noninvasive OCT images can be helpful to understand abnormal WAI measurements. Mucoid MEEs decrease the power absorbance more than serous MEEs, and the greater amounts of MEE decreases the power absorbance, especially at higher (>2 kHz) frequencies. As both the type and amount of MEE can significantly affect WAI measurements, further investigations to correlate acoustic measurements with physical characteristics of middle ear conditions in vivo is needed.

The diagnosis and treatment of otitis media (OM), a common childhood infection, is a significant burden on the healthcare system. Diagnosis relies on observer experience via otoscopy, although for non-specialists or inexperienced users, accurate diagnosis can be difficult. In past studies, optical coherence tomography (OCT) has been used to quantitatively characterize disease states of OM, although with the involvement of experts to interpret and correlate image-based indicators of infection with clinical information. In this paper, a flexible and comprehensive framework is presented that automatically extracts features from OCT images, classifies data, and presents clinically relevant results in a user-friendly platform suitable for point-of-care and primary care settings. This framework was used to test the discrimination between OCT images of normal controls, ears with biofilms, and ears with biofilms and middle ear fluid (effusion). Predicted future performance of this classification platform returned promising results (90%+ accuracy) in various initial tests. With integration into patient healthcare workflow, users of all levels of medical experience may be able to collect OCT data and accurately identify the presence of middle ear fluid and/or biofilms.

Wideband acoustic immittance (WAI) measurements characterize middle ear function, but effects of pathologies are not thoroughly understood. Co-acquired OCT and WAI measurements from pediatric subjects were correlated to investigate varied acoustic responses in otitis media.

Otitis media (OM) is a common ear infection and a leading cause of conductive hearing loss in the pediatric population. Current technologies such as otoscopy, pneumatic otoscopy, tympanometry, and acoustic reflectometry are used to diagnose OM, which can reasonably diagnose the infection with a sensitivity and specificity of 50–90% and 60–90%, respectively. However, these techniques provide limited information about the physical architecture of the tympanic membrane (TM), or what may lie behind it. Here, we report the detection of nanometer-scale structural changes of the TM using nano-sensitive optical coherence tomography (nsOCT). In total, an image dataset from 65 pediatric subjects from three different groups (normal, acute OM, and chronic OM) and with longitudinal image-based analysis of ear infections were included in this study. The nsOCT data were correlated with physician diagnosis and with OCT thickness measurements and were found to be in good agreement with these results. We report that nsOCT detects in vivo structural deformations of the TM earlier than OCT alone, and enhances the detection sensitivity of OCT measurements. This unique technique for early detection of nano-scale structural modifications in the TM has the potential to aid in our understanding of microbiological effects, and possibly for early diagnosis and more effective treatment of OM.

Pneumatic otoscopy to assess the mobility of the tympanic membrane (TM) is a highly recommended diagnostic method of otitis media (OM), a widespread middle ear infection characterized by the fluid accumulation in the middle ear. Nonetheless, limited depth perception and subjective interpretation of small TM displacements have challenged the appropriate and efficient examination of TM dynamics experienced during OM. In this paper, a pneumatic otoscope integrated with low coherence interferometry (LCI) was adapted with a controlled pressure-generating system to record the pneumatic response of the TM and to estimate middle ear pressure (MEP). Forty-two ears diagnosed as normal (n = 25), with OM (n = 10), or associated with an upper respiratory infection (URI) (n = 7) were imaged with a pneumatic LCI otoscope with an axial, transverse, and temporal resolution of 6 µm, 20 µm, and 1 msec, respectively. The TM displacement under pneumatic pressure transients (a duration of 0.5 sec with an intensity of ± 150 daPa) was measured to compute two metrics (compliance and amplitude ratio). These metrics were correlated with peak acoustic admittance and MEP from tympanometry and statistically compared via Welch’s t-test. As a result, the compliance represents pneumatic TM mobility, and the amplitude ratio estimates MEP. The presence of a middle ear effusion (MEE) significantly decreased compliance (p

In an institutional review board-approved study, 25 pediatric subjects diagnosed with chronic or recurrent otitis media were observed over a period of six months with optical coherence tomography (OCT). Subjects were followed throughout their treatment at the initial patient evaluation and preoperative consultation, surgery (intraoperative imaging), and postoperative follow-up, followed by an additional six months of records-based observation. At each time point, the tympanic membrane (at the light reflex region) and directly adjacent middle-ear cavity were observed in vivo with a handheld OCT probe and portable system. Imaging results were compared with clinical outcomes to correlate the clearance of symptoms in relation to changes in the image-based features of infection. OCT images of most all participants showed the presence of additional infection-related biofilm structures during their initial consultation visit and similarly for subjects imaged intraoperatively before myringotomy. Subjects with successful treatment (no recurrence of infectious symptoms) had no additional structures visible in OCT images during the postoperative visit. OCT image findings suggest surgical intervention consisting of myringotomy and tympanostomy tube placement provides a means to clear the middle ear of infection-related components, including middle-ear fluid and biofilms. Furthermore, OCT was demonstrated as a rapid diagnostic tool to prospectively monitor patients in both outpatient and surgical settings.

We report nano-sensitive optical coherence tomography (nsOCT) structural changes of the in vivo human tympanic membrane (TM) under normal and infected conditions. nsOCT enables diagnostics which may impact the clinical treatment of middle-ear infection.

We report a unique case in which a 57-year-old man with an 8-year history of late recurrent post-tympanostomy tube otorrhea (PTTO) was found to harbor Bacillus subtilis, an aerobic endospore-forming bacillus that is typically resistant to chemical and physical agents because of its unique life cycle. Removal of the patient's tympanostomy tube resulted in complete resolution of his long-standing otorrhea. We also review the etiologies of and treatment strategies for early, late, chronic, and recurrent PTTO. We conclude that regardless of the etiology, a patient with persistent or recurrent PTTO should consider undergoing removal of the ventilation tube.

To describe a successful paradigm for the treatment of large acoustic neuromas (vestibular schwannomas).Retrospective case review.Tertiary referral center.The charts of 2,875 acoustic neuroma patients at Michigan Ear Institute were reviewed to identify 153 patients who underwent surgical resection for large acoustic neuromas (=3 cm) between 2000 and 2009.Staged surgical resection or single stage surgery with or without adjuvant stereotactic radiosurgery.Postoperative facial nerve outcomes are reported using the House-Brackmann (HB) facial nerve grading scale and compared with historical controls from a literature review. Rates of adverse outcomes are also reported.Seventy-five patients underwent staged surgical resection of their tumors, whereas 78 patients underwent either single stage surgery or surgery with subsequent stereotactic radiosurgery. Eighty-one percent of patients in the staged surgical resection group had a postoperative HB Grade I or II facial nerve function compared with 75% in the single stage surgical group. Overall, 78% of patients in the current study had HB Grade I or II after treatment compared with a mean of 53% in the literature for similar sized tumors. Our methods including the decision to use staged surgery when necessary, dissection of tumor with stimulating dissector-directed intraoperative monitoring, and use of adjuvant stereotactic radiosurgery are described.Using the described paradigm, large acoustic neuromas can be successfully treated with either staged or single-stage surgical resection with or without adjuvant radiosurgery to obtain more favorable facial nerve outcomes than historically reported controls while minimizing morbidity for the patient.

Otitis media is the leading cause of hearing loss in children. It is commonly associated with fluid in the ear, which can result in up to 45 dB of hearing loss for extended periods of time during a child's most important developmental years. Accurate assessment of middle ear effusions is an important part of understanding otitis media. Current technologies used to diagnose otitis media with effusion are pneumatic otoscopy, tympanometry, and acoustic reflectometry. While all of these techniques can reasonably diagnose the presence of an effusion, they provide limited information about the infection present behind the tympanic membrane.We have developed a technique based on low-coherence interferometry-a non-invasive optical ranging technique capable of sensing depth-resolved microscopic scattering features through the eardrum-to quantify eardrum thickness and integrity, as well as detect any effusion, purulence, or biofilm behind the tympanic membrane. In this manuscript, the technique is coupled with a pneumatic otoscope to measure minute deflections of the tympanic membrane from insufflation pressure stimuli. This results in quantitative measurements of tympanic membrane mobility, which may be used to gain a better understanding of the impact of infection on the membrane dynamics. A small pilot study of 15 subjects demonstrates the ability of pneumatic low-coherence interferometry to quantitatively differentiate normal ears from ears with effusions present. Analysis of the strengths and weaknesses of the technique, as well as focus areas of future research, is also discussed.

Eustachian tube dysfunction can cause fluid to collect within the middle ear cavity and form a middle ear effusion (MEE). MEEs can persist for weeks or months and cause hearing loss as well as speech and learning delays in young children. The ability of a physician to accurately identify and characterize the middle ear for signs of fluid and/or infection is crucial to provide the most appropriate treatment for the patient. Currently, middle ear infections are assessed with otoscopy, which provides limited and only qualitative diagnostic information. In this study, we propose a method utilizing cross-sectional depth-resolved optical coherence tomography to noninvasively measure the diffusion coefficient and viscosity of colloid suspensions, such as a MEE. Experimental validation of the proposed technique on simulated MEE phantoms with varying viscosity and particulate characteristics is presented, along with some preliminary results from in vivo and ex vivo samples of human MEEs. In vivo Optical Coherence Tomography (OCT) image of a human tympanic membrane and Middle Ear Effusion (MEE) (top), with a CCD image of the tympanic membrane surface (inset). Below is the corresponding time-lapse M-mode OCT data acquired along the white dotted line over time, which can be analyzed to determine the Stokes-Einstein diffusion coefficient of the effusion.

Objective To assess the incidence of osteoradionecrosis (ORN) of the temporal bone after surgery with radiotherapy for malignant parotid tumors. Setting A tertiary care, academic medical center. Patients All patients who underwent surgical resection with postoperative radiotherapy (RT) for a malignant parotid tumor between July 1988 and July 2007. Interventions A retrospective chart analysis to determine the extent of surgery, the RT parameters, and the incidence of ORN of the temporal bone. Main outcome measures The incidence of ORN in 3 subgroups of patients. Results The 221 patients with malignant parotid tumors who underwent surgical resection with postoperative RT were divided into groups 1, parotidectomy only; 2, parotidectomy with mastoidectomy; and 3, parotidectomy with subtotal petrosectomy. The overall incidence of temporal bone ORN in group 1 was 2 (2%) of 106; in group 2, 8 (13%) of 64; and in group 3, 0 (0%) of 51. Conclusion The incidence of temporal bone ORN is higher after mastoidectomy for facial nerve identification or resection in patients undergoing parotidectomy with postoperative radiotherapy. Oversew of the ear canal with mastoid obliteration should be considered in this subgroup of patients to avoid this long-term complication of radiotherapy used in the treatment of malignant parotid tumors.

Purpose The neurotherapeutic effects of nerve electrical stimulation and gonadal steroids have independently been demonstrated. The purpose of this study was to investigate the therapeutic potential of a combinatorial treatment strategy of electrical stimulation and gonadal steroids on peripheral nerve regeneration. Methods Following a facial nerve crush axotomy in gonadectomized adult male rats, testosterone propionate (TP), dihydrotestosterone (DHT), or estradiol (E(2)) was systemically administered with/without daily electrical stimulation of the proximal nerve stump. Facial nerve outgrowth was assessed at 4 and 7 days post-axotomy using radioactive labeling. Results Administration of electrical stimulation alone reduced the estimated delay in sprout formation but failed to accelerate the overall regeneration rate. Conversely, TP treatment alone accelerated the regeneration rate by approximately 10% but had no effect on the sprouting delay. Combining TP with electrical stimulation, however, maintained the enhanced rate and reduced the sprouting delay. DHT treatment alone failed to alter the regeneration rate but combining it with electrical stimulation increased the rate by 10%. E(2) treatment alone increased the regeneration rate by approximately 5% but with electrical stimulation, there was no additional effect. Conclusions Electrical stimulation and gonadal steroids differentially enhanced regenerative properties. TP, an aromatizable androgen, augmented regeneration most, suggesting a synergism between androgenic and estrogenic effects. Therapeutically, combining electrical stimulation with gonadal steroids may boost regenerative properties more than the use of either treatment alone.

We report a unique case in which a 57-year-old man with an 8-year history of late recurrent post-tympanostomy tube otorrhea (PTTO) was found to harbor Bacillus subtilis, an aerobic endospore-forming bacillus that is typically resistant to chemical and physical agents because of its unique life cycle. Removal of the patient's tympanostomy tube resulted in complete resolution of his long-standing otorrhea. We also review the etiologies of and treatment strategies for early, late, chronic, and recurrent PTTO. We conclude that regardless of the etiology, a patient with persistent or recurrent PTTO should consider undergoing removal of the ventilation tube.

This six-volume series has been compiled to introduce current, up-to-date concepts concerning the diagnosis, evaluation, and management rationale of the various conditions that otorhinolaryngologists encounter in their clinics, hospitals, and operating rooms. It has been our goal to keep this information complete yet concise. -- Milind V. Kirtane and Chris E. de Souza, Series Editors Head and Neck Surgery is a comprehensive textbook that provides detailed information on the latest epidemiology, diagnostics, nutritional support, and emerging technology and therapeutics used to treat head and neck cancer. It will serve as a reference guide for physicians and non-physicians who diagnose, treat, and rehabilitate patients with head and neck tumors. Key Features: * Multidisciplinary care of patients with tumors of the head and neck region* Intraoperative navigation and robotic surgery for head and neck neoplasms* Endoscopic approaches to the anterior skull base* Image guidance for sinus tumors* Minimally invasive techniques in head and neck surgery The contributors to this volume are internationally recognized experts in head and neck surgery, plastic surgery, and oral and maxillofacial surgery, informing the book with a wealth of knowledge in these disciplines.

Objective: Describe the presentation, tumor characteristics, and postoperative lower cranial nerve function following surgery for jugular foramen tumors.Method: Thirty jugular foramen tumor resections performed between 1989 and 2009 were reviewed. The mean age was 48.2 years (range, 18.6-77.7 years) at time of presentation. Surgical approaches included infratemporal fossa (70%), retrosigmoid (23%), transtemporal (20%), transcondylar (17%), and transcervical (17%). The mean follow-up was 4.6 years.Results: Combined surgical approaches were used in over 50% of the cases, and 60% underwent preoperative tumor embolization. Tinnitus was the most common presenting symptom, and middle ear or neck mass was the most common presenting sign. The most common diagnosis was paraganglioma. Six patients required tracheotomy, and 8 had feeding tubes at discharge. Fifty-seven percent of patients underwent speech or swallow therapy, 43% were treated with vocal cord injections, and 17% underwent medialization thyroplasty. Ce...

To assess the incidence of osteoradionecrosis (ORN) of the temporal bone after surgery with radiotherapy for malignant parotid tumors.A tertiary care, academic medical center.All patients who underwent surgical resection with postoperative radiotherapy (RT) for a malignant parotid tumor between July 1988 and July 2007.A retrospective chart analysis to determine the extent of surgery, the RT parameters, and the incidence of ORN of the temporal bone.The incidence of ORN in 3 subgroups of patients.The 221 patients with malignant parotid tumors who underwent surgical resection with postoperative RT were divided into groups 1, parotidectomy only; 2, parotidectomy with mastoidectomy; and 3, parotidectomy with subtotal petrosectomy. The overall incidence of temporal bone ORN in group 1 was 2 (2%) of 106; in group 2, 8 (13%) of 64; and in group 3, 0 (0%) of 51.The incidence of temporal bone ORN is higher after mastoidectomy for facial nerve identification or resection in patients undergoing parotidectomy with postoperative radiotherapy. Oversew of the ear canal with mastoid obliteration should be considered in this subgroup of patients to avoid this long-term complication of radiotherapy used in the treatment of malignant parotid tumors.

Objectives/Hypothesis: The purpose of this study was to compare functional recovery and motor nerve conduction following a distal extratemporal crush injury of the facial nerve to a more proximal intratemporal crush injury. Study Design: Prospective, controlled animal study. Methods: Adult male Sprague-Dawley rats were divided into four experimental groups: 1) extratemporal crush, 2) extratemporal sham-operated, 3) intratemporal crush, and 4) intratemporal sham-operated. Each group had an n of 4–9. The facial nerve was crushed near its exit from the stylomastoid foramen for extratemporal facial nerve injuries and within the facial canal in the temporal bone for intratemporal facial nerve injuries. Recovery times for the return of facial nerve functional parameters were compared between the two injury models. Motor nerve conduction studies were also done weekly to quantify the changes in peak amplitude and latency of evoked response. Results: Rats receiving the extratemporal facial nerve injury recovered full facial function by ∼2 weeks postoperative (wpo) and displayed normal peak amplitude and latency recordings by 4 wpo. In comparison, rats receiving the intratemporal facial nerve injury failed to reach complete functional recovery at the end of 8 wpo. Although latency of evoked response returned to normal by 2 weeks following the intratemporal injury, peak amplitude remained ∼70% below normal at the end of 8 wpo. Conclusions: An intratemporal crush of the facial nerve leads to significantly delayed functional recovery and decreased motor nerve conduction as compared to an extratemporal crush, indicating that the location of injury strongly influences the recovery outcome. Laryngoscope, 2009

ObjectivesTo present the clinical and radiographic findings in 8 patients with unusual primary tumors of the temporomandibular joint (TMJ).MethodsThis was a retrospective chart review of all patients with neurotologic manifestations caused by primary TMJ tumors seen at our tertiary care, academic medical center between 7/88-; 7/07.Results8 patients were identified with primary TMJ tumors that caused a variety of neurotologic manifestations, including trismus, otalgia, tinnitus, hearing loss, aural fullness, headache, facial pain, and otorrhea. Tumor histology included chondroma, chondroblastoma, osteoma, giant cell tumor, synovial chondromatosis, and osteosarcoma. Anterior external auditory canal involvement required partial petrosectomy in all 8 patients. Despite aggressive surgical resection and radiotherapy, only 5 of 8 patients are disease-free, with a mean follow-up of 7.2 years.ConclusionsPrimary tumors of the TMJ, although rare, can cause a variety of common neurotologic manifestations. A complete ...

OBJECTIVE: 1. Explain the need for an animal model to study intratemporal injuries to the facial nerve. 2. Describe the first rat model of intratemporal facial nerve crush injury. STUDY DESIGN: Animal surgery protocol. SETTING: Animal laboratory. SUBJECTS AND METHODS: Although intracranial and extratemporal facial nerve injury models have been described, an intratemporal injury model is lacking. This model is needed for translational research aimed at improving nerve recovery in the fallopian canal. The laboratory setup, anatomy, and surgical technique are described. RESULTS: The success of the facial nerve crush injuries was apparent upon physical examination of the animals. Our animals were followed for at least eight weeks postoperatively, and no signs of significant weight loss or physical distress were observed. INTRODUCTION • Crush injury is favored over nerve transection because it eliminates variables associated with neural re-anastamosis. • Although intracranial facial nerve transection, extratemporal crush and transection, and rat middle ear anatomy have been well described, an intratemporal injury model is lacking1-5. • The purpose of this paper is to describe a simple, reliable, and reproducible method to create a crush injury in an intratemporal segment of the adult rat facial nerve. TECHNIQUE • A curvilinear incision was made on the shaved and prepped postauricular skin approximately five millimeters (mm) behind the ear. The skin was elevated in the subdermal plane towards the ear canal. • The sternocleidomastoid tendon was divided to provide better exposure of the nerve. The dorsal and caudal aspects of the ear canal were incised so that the canal incision was immediately lateral to the tympanic membrane. • The temporalis muscle inserting on this ridge anteriorly and the rhomboid capitis muscle inserting posteriorly were sharply incised and gently dissected caudally and rostrally off of the ridge of bone thereby exposing an approximately one centimeter portion of bone superior to the tympanic membrane (figure 2). • A 3 mm cutting burr was used to remove the lateral bony aspect of the epitympanic region, thereby exposing the ossicles. The ossicles were removed. • Using a 1 mm diamond burr, the bone covering the facial nerve was progressively removed beginning at the posterior aspect of the stylomastoid foramen and continuing antero-medially. Twitching of the ipsilateral vibrissae was often noted when approaching the intratemporal facial nerve. • Jewler’s forceps were then inserted through the middle ear, and the intratemporal portion of the facial nerve within the medial wall of the superior middle ear cavity was crushed firmly for one minute. • Loss of ipsilateral eye blink and vibrissae orientation and movement was evidence of a successful crush injury. Figure 1. An intact facial nerve is shown as it exits the stylomastoid foramen (solid arrow). The bony ridge (dashed arrow) separating the temporalis muscle anteriorly and the rhomboid capitis muscle posteriorly and the location of the large maxillary vein (arrowhead) running along the anterior-inferior quadrant of the tympanic rim are also pictured. Figure 2. A rat facial nerve is shown immediately after a controlled intratemporal crush injury. The intratemporal segment of the nerve is shown after it has been skeletonized (*) from the stylomastoid foramen (solid arrow) to the crush site (dotted arrow). RESULTS & CONCLUSION • Our group had reproducible surgical success amongst various investigators with multiple animals. • Animals were followed for at least eight weeks postoperatively, and no signs of significant weight loss or physical distress were observed. • This technique offers the unique opportunity to study intratemporal facial nerve crush injuries in the adult rat. • Future directions include exploring new therapeutic methods of enhancing neuronal cell survival and increasing neural regeneration following intratemporal nerve injury. REFERENCES 1. Hetzler LE, Sharma N, Tanzer L, et al. Accelerating functional recovery after rat facial nerve injury: Effects of gonadal steroids and electrical stimulation. Otolaryngol Head Neck Surg 2008;139:62-7. 2. Lal D, Hetzler LT, Sharma N, et al. Electrical stimulation facilitates rat facial nerve recovery from a crush injury. Otolaryngol Head Neck Surg 2008;139:68-73. 3. Mattsson P, Delfani K, Janson AM, et al. Motor neuronal and glial apoptosis in the adult facial nucleus after intracranial nerve transection. J Neurosurg 2006;104:411-8. 4. Hellstrom S, Salen B, Stenfors LE. Anatomy of the rat middle ear. A study under the dissection microscope. Acta Anat (Basel) 1982;112:346-52. 5. Judkins RF, Li H. Surgical anatomy of the rat middle ear. Otolaryngol Head Neck Surg 1997;117:438-47. 6. Sharma N, Cunningham, K, Porter RG, et al. Comparison of extratemporal and intratemporal facial nerve injury models. Laryngoscope 2009; Published online ahead of print. This work was funded by United States Department of Veterans Affairs pilot grant #B6175R.