Evidence of hemispheric specialization in marmosets (Callithrix penicillata) using tympanic membrane thermometry

Recent studies have employed tympanic thermometry to assess lateralization of cognitive and emotional functions in primates. However, no studies using this technique have investigated the possibility of hemispheric specialization in New World monkeys. Therefore, the aim of the present study was to investigate tympanic membrane (TM) temperature asymmetries and their possible correlation with stress responses in marmosets (Callithrix penicillata). Infrared TM thermometry was completed bilaterally in 24 animals (14 males and 10 females) during a stressful situation of capture and restraint. There were no significant differences between gender. A significant negative correlation was observed between TM temperature of the right ear and the number of captures (r = -0.633; P<0.001). Subjects with a more frequent previous history of captures (5 to 9 captures; N = 11) showed lower TM temperature when compared to those with fewer previous captures (1 to 4 captures; N = 13). No differences were observed for the left TM temperature. These results suggest that under intense emotional challenge (capture and restraint) there is a stronger activation of the neural structures situated in the right brain hemisphere. Taken together, the data reveal for the first time evidence of hemispheric specialization in emotional physiological processing in a New World monkey.

The effect of flying and low humidity on the admittance of the tympanic membrane and middle ear system

Many passengers experience discomfort during flight because of the effect of low humidity on the skin, eyes, throat, and nose. In this physiological study, we have investigated whether flight and low humidity also affect the tympanic membrane. From previous studies, a decrease in admittance of the tympanic membrane through drying might be expected to affect the buffering capacity of the middle ear and to disrupt automatic pressure regulation. This investigation involved an observational study onboard an aircraft combined with experiments in an environmental chamber, where the humidity could be controlled but could not be made to be as low as during flight. For the flight study, there was a linear relationship between the peak compensated static admittance of the tympanic membrane and relative humidity with a constant of proportionality of 0.00315 mmho/% relative humidity. The low humidity at cruise altitude (minimum 22.7 %) was associated with a mean decrease in admittance of about 20 % compared with measures in the airport. From the chamber study, we further found that a mean decrease in relative humidity of 23.4 % led to a significant decrease in mean admittance by 0.11 mmho [F(1,8) = 18.95, P = 0.002], a decrease of 9.4 %. The order of magnitude for the effect of humidity was similar for the flight and environmental chamber studies. We conclude that admittance changes during flight were likely to have been caused by the low humidity in the aircraft cabin and that these changes may affect the automatic pressure regulation of the middle ear during descent. © 2013 Association for Research in Otolaryngology.

The prevalence of tympanic membrane and related middle ear pathology in children:a large longitudinal cohort study followed from birth to age ten

OBJECTIVE: To record with video-otoscopy the appearance of the tympanic membranes of a cross section of children aged 9 to 10 years. STUDY DESIGN: Cross-sectional study nested within an established longitudinal study of childhood development, the Avon Longitudinal Study of Parents and Children. SETTING: South West England, U.K. PARTICIPANTS: Approximately 6908 of 7261 children with ages ranging from 105 to 140 months born between April 1, 1991, and December 31, 1992, were examined by trained technicians with video-otoscopy. MAIN OUTCOME MEASURES: Two photographs were taken of each child's tympanic membranes to show the features of the pars tensa and the pars flaccida. RESULTS: In just less than three quarters of the children, both ears were normal. Retraction of the pars flaccida was present in 9.6% of children, and that of the pars tensa was present in 7.9%. Most of these changes were mild with few severe retractions. There were 15 cases of overt or suspected cholesteatoma. CONCLUSION: The tympanic membrane changes reflect most of the middle ear disease seen in 9- to 10-year-old children. The prevalence is low, and few children have serious disease at this stage.

Colesteatoma em idade pediátrica: análise retrospectiva de 12 anos de experiência do Hospital Fernando Fonseca

Objectivo: revisão de casos de colesteatoma em idade pediátrica do HFF durante um período de 12 anos. Desenho do estudo: retrospectivo. Material e métodos: análise de 30 casos de cirurgia para colesteatoma em doentes dos 0 - 18 anos de Janeiro de 2000 a Dezembro de 2011. Resultados: o colesteatoma inicial foi extenso na maioria dos casos. Realizou-se mastoidectomia com técnica aberta (66,7%), mastoidectomia com técnica fechada (26,7%), aticomia transmeática (3,3%) e remoção de colesteatoma da membrana timpânica (3,3%). O GAP pós-operatório médio foi de 22,5 dB, com GAP 0-10dB em 16,7%, GAP 11-20dB em 10%, GAP 21-30 dB em 30%, mais de 30dB em 16,7% e desconhecido em 26,7%. A taxa de recorrência de colesteatoma foi de 23,3% Conclusões: Na nossa amostra o colesteatoma foi extenso e agressivo. Realizámos mastoidectomia com técnica aberta na maioria dos casos. Para obter bons resultados a abordagem deverá ser individualizada, atendendo a factores clínicos, anatómicos e capacidade de adesão à terapêutica.

Intratympanic application of an antiviral agent for the treatment of Ménière's disease.

It has been suggested that Ménière's disease is part of a polyganglionitis in which symptoms result from the reactivation of neurotropic virus within the internal auditory canal, and that intratympanic applications of an antiviral agent might be an efficient therapy. In 2002, we performed a pilot study ending with encouraging results. Control of vertigo was achieved in 80% of the 17 patients included. We present here a prospective, double-blind study, with a 2-year follow-up, in 29 patients referred by ENT practitioners for a surgical treatment after failure of a medical therapy. The participation in the study was offered to patients prior to surgery. A solution of ganciclovir 50 mg/ml or of NaCl 9% was delivered for 10 consecutive days via a microwick inserted into the tympanic membrane in the direction of the round window or through a ventilation tube. One patient was withdrawn from the study immediately after the end of the injections. He could not complete the follow-up period, because of persisting vertigo. As he had received the placebo, he was then treated with the solution of ganciclovir. Symptoms persisted and he underwent a vestibular neurectomy. Among the remaining 28 patients, surgery could be postponed in 22 (81%). Surgery remained necessary to control vertigo in 3 patients from the group that received the antiviral agent, and in 3 from the control group. Using an analogical scale, patients of both groups indicated a similar improvement of their health immediately after the intratympanic injections. The scores obtained with a 36-item short-form health survey quality of life questionnaire and the Dizziness Handicap Inventory were also similar for both groups. In conclusion, most patients were improved after the intratympanic injections, but there was no obvious difference between the treated and control groups. The benefit might be due to the middle ear ventilation or reflect an improvement in the patients' emotional state.

Etat confusionnel avec pneumencéphale: quel est votre diagnostic [A patient with confusion and pneumocephalus: what is your diagnosis?]

We report the case of a 58 year old male who presented with acute meningoencephalitis and pneumocephalus (intracranial air) visualized on head CT scan. Despite the lack of typical clinical signs such as retroauricular tenderness, red tympanic membrane or otorrhea, mastoiditis was suggested by head CT scan. The patient made a full recovery after mastoidectomy and six weeks of antibiotic therapy. Streptococcus pneumoniae grew from a surgical purulent mastoid tissue sample. Mastoiditis and its complications are rare in adults. A high level of clinical suspicion is needed when a patient presents with encephalitis of unclear origin.

Resultate und ausser- gewöhnliche Komplikationen der Chirurgie der Gehörgangexostosen [Results and extraordinary complications of surgery for exostoses of the external auditory canal].

We present a retrospective study on 22 operations of exostosis of the external auditory canal in 20 patients. 8 patients were passionated by water sports. The most frequent indication for surgery (13 operations) was recurrent external otitis or ceruminal obstruction. In 7 cases the need for a wider access to the middle ear indicated surgery. Surgery was usually performed as an outpatient procedure, maximum hospitalization was 3 days. The mean healing period was 6 (3-10) weeks. Mean follow up was 43 (3-110) months. There were no severe intraoperative complications such as facial paresis, lesions of the ossicles or of the inner ear. As intraoperative complications we found 2 perforations of the tympanic membrane, 2 expositions of the capsule of the mandibular joint, one of which was followed by chronic pain. As postoperative complications we found an early soft tissue stenosis of the external auditory canal and one late soft tissue stenosis which recurred after revision surgery. No recurrence of exostosis was seen. We describe an up to now unknown complication: the appearance of bilateral petrositis caused by staphylococcus epidermidis after bilateral surgery in an otherwise healthy patient. This study confirms that severe complications are rare, minor ones however relatively common. And that also minor complications may have a troublesome follow. Therefore and because of the potential of severe complications indication for surgery must be made cautiously and risks of the operation must not be underestimated.

Macroscopic description of the external and middle ear of paca (Cuniculus paca Linnaeus, 1766)

Abstract: Paca (Cuniculus paca), one of the largest rodents of the Brazilian fauna, has inherent characteristics of its species which can conribute as a new option for animal experimantation. As there is a growing demand for suitable experimental models in audiologic and otologic surgical research, the gross anatomy and ultrastructural ear of this rodent have been analyzed and described in detail. Fifteen adult pacas from the Wild Animals Sector herd of Faculdade de Ciências Agrárias e Veterinárias, Unesp-Jaboticabal, were used in this study. After anesthesia and euthanasia, we evaluated the entire composition of the external ear, registering and ddescribing the details; the temporal region was often dissected for a better view and detailing of the tympanic bulla which was removed and opened to expose the ear structures analyzed mascroscopically and ultrastructurally. The ear pinna has a triangular and concave shape with irregular ridges and sharp apex. The external auditory canal is winding in its path to the tympanic mebrane. The tympanic bulla is is on the back-bottom of the skull. The middle ear is formed by a cavity region filled with bone and membranous structures bounded by the tympanic membrane and the oval and round windows. The tympanic membrane is flat and seals the ear canal. The anatomy of the paca ear is similar to the guinea pig and from the viewpoint of experimental model has major advantages compared with the mouse ear.

The effect of Nystatin on the inner ear : an experimental guinea pig study

Objectifs: Le Nystatin est un antibiotique efficace pour le traitement d’otomycose. Bien que sa sécurité au niveau de l’oreille externe soit bien établie, son utilisation n’est pas recommandée lorsqu’il y a une perforation tympanique. L’objectif de cette étude est d’évaluer le potentiel ototoxique du Nystatin lorsque celui-ci est appliqué directement au niveau de l’oreille moyenne. Méthodes: Nous avons fait une étude expérimentale avec 18 cochons d’Indes de souche Hartley que nous avons divisés en deux groupes. En exposant l’oreille moyenne de chaque animal au Nystatin (groupe I) ou à la néomycine (groupe II) et chaque oreille controlatérale à une solution physiologique (NaCl), la fonction auditive a été évaluée avec un test de potentiels évoqués auditif du tronc cérébral avant et après les injections. Une étude par microscopie électronique a permis une comparaison histologique de l’état des cellules ciliées cochléaires entre les 2 groupes. Résultats: Les pertes auditives moyennes du groupe « Nystatin » étaient de 13.0 dB et comparables aux pertes moyennes observées dans les oreilles ayant été injectées avec du NaCl (4.0 dB dans le groupe I et 15.1 dB dans le groupe II). Le groupe de contrôle « néomycine » a subi une perte auditive moyenne de 39.3 dB, ce qui représente une différence cliniquement et statistiquement significative (p<0.001). L’étude histologique avec une microscopie à balayage électronique a démontré une conservation de l’architecture des cellules ciliées cochléaires dans les groupe Nystatin et NaCl. La néomycine a causé une destruction marquée de ces structures. Conclusions: Le Nystatin ne provoque pas d’atteinte auditive ni de destruction des cellules ciliées externes après injection directe dans l’oreille moyenne chez le cochon d’Inde.

Variables that influence the real-ear response of the TDH-49 earphone

This paper discusses a study performed to determine whether anatomical features of the outer ear affect the sound stimulus delivered by earphone to the tympanic membrane.

Seqüência de moebius: Manifestações clínicas e avaliação auditiva

Introduction: Children with Moebius syndrome may present paralysis of cranial nerves III, IV, V, VI, VII, VIII, IX, X and XII, compromising motor and sensorial functions. Hands and feet defects (syndactyly, equinovarus and arthrogryposis) are frequently associated. These manifestations can be attributed to the use of misoprostol during pregnancy to induce abortion. Study design: Clinical prospective. Aim: To evaluate the main clinical manifestations, hearing acuity and possible etiologic factors in children with Moebius syndrome. Material and method: The children were submitted to clinical, otolaryngological and hearing acuity assessment. Hearing acuity was evaluated through behavioral tests, pure tone audiometry, tympanometry and auditory brainstem response (ABR). We investigated possible etiologic factors. Results: Three boys and two girls were evaluated. The main manifestations were: facial paralysis, paralysis of masseter muscle, defects in dental occlusion, retraction of tympanic membrane, equinovarus, oblique palpebral fissure and tongue atrophy. Conductive hearing loss was detected in three children and sensorineural hearing loss in one child. The use of misoprostol during pregnancy was reported by four mothers. Conclusions: The children with Moebius syndrome evaluated in the present study manifested palsies of various cranial nerves, especially V, VII and XII nerves, responsible for motor and sensorial alterations. Inadequate eustachian tube function associated to conductive hearing loss was frequent. The use of misoprostol during pregnancy was reported by the mothers and it was considered a possible etiologic factor.

Anatomia macroscópica e ultraestrutural da orelha da paca (Cuniculus paca, Linnaeus, 1766)

Pós-graduação em Cirurgia Veterinária - FCAV

Produção e utilização de material didático sobre fisiologia da audição e neurofisiologia

The teaching of hearing physiology requires an knowledge integration of Human Anatomy, Biophysics, more precisely Bioacoustics and Bioelectrogenesis, as well as Neurophysiology. Students present difficulty to build knowledge about functional mechanisms of sound conduction and sensory transduction, especially if the elements are not visible forms, as the middle and inner ear structures. To make the teaching about hearing physiology and sensory perception easier, was produced a set of didactical materials about the subject. At first, a resin model that faithfully describes the anatomical relationship of the ossicles with the tympanic membrane was developed. Subsequently, a second model that, besides illustrates the mechanism of acoustic impedance overcoming, also reveals how acoustic sensorial transduction occurs in inner ear, was designed and produced. In the third didactical model, are visualized, through students interaction, areas of the cerebral cortex that interpret the different sensory modalities. In addition, were created three educational videos about hearing problems and a site on Human Hearing Physiology, available on Institute of Biosciences website. The results of this course conclusion monograph are presented in the form of articles that were submitted to Journal Physics in the School and the Journal of the Nucleus of Teaching

Anatomical and functional evaluation of tympanoplasty using a transitory natural latex biomembrane implant from the rubber tree Hevea brasiliensis

PURPOSE: To compare the role of transitory latex and sylastic (R) implants in tympanoplasty on the closure of tympanic perforations. METHODS: A randomized double-blind prospective study was conducted on 107 patients with chronic otitis media submitted to underlay tympanoplasty and divided at random into three groups: control with no transitory implant, latex membrane group, and sylastic (R) membrane group. RESULTS: Greater graft vascularization occurred in the latex membrane group (p<0.05). Good biocompatibility was obtained with the use of the latex and silicone implants, with no effect on the occurrence of infection, otorrhea or otorragy. CONCLUSION: The use of a transitory latex implant induced greater graft vascularization, with a biocompatible interaction with the tissue of the human tympanic membrane.

Surgical complications in 550 consecutive cochlear implantation

Cochlear implantation is a safe and reliable method for auditory restoration in patients with severe to profound hearing loss. Objective: To describe the surgical complications of cochlear implantation. Materials and Methods: Information from 591 consecutive multichannel cochlear implant surgeries were retrospectively analyzed. All patients were followed-up for at least one year. Forty-one patients were excluded because of missing data, follow-up loss or middle fossa approach. Results: Of 550 cochlear implantation analyzed, 341 were performed in children or adolescents, and 209 in adults. The mean hearing loss time was 6.3 +/- 6.7 years for prelingual loss and 12.1 +/- 11.6 years for postlingual. Mean follow-up was 3.9 +/- 2.8 years. Major complications occurred in 8.9% and minor in 7.8%. Problems during electrode insertion (3.8%) were the most frequent major complication followed by flap dehiscence (1.4%). Temporary facial palsy (2.2%), canal-wall lesion (2.2%) and tympanic membrane lesion (1.8%) were the more frequent minor complications. No death occurred. Conclusion: There was a low rate of surgical complications, most of them been successfully managed. These results confirm that cochlear implant is a safe surgery and most surgical complications can be managed with conservative measures or minimal intervention.