Otite média e interna com extensão para tronco encefálico em buldogue francês / Otitis media and internal with brainstem extension in a French bulldog

Background: Otitis is a frequent condition in dogs, with a multifactorial etiology covering primary causes, predisposing and perpetuating factors. It is characterized by an inflammatory process of structures that make up the auditory system, with prevalence data ranging from 15 to 20%, which can occur in any age group and without sex predisposition. According to the location, it can be classified as uni or bilateral, affecting the outer, middle and / or inner ear, the latter two being associated with neurological changes such as vestibulopathy, facial nerve paresis and Horner's syndrome. The morbidity and mortality of otitis media and internal may increase with delay in diagnosis, resulting in delay in the correct treatment, and the extension to brainstem is described in felines and considered rare in dogs. The present study aims to report an atypical case of otitis media and internal, with extension to the brain parenchyma in a brachycephalic dog. Case: A 3-year-old bitch French Bulldog was seen, weighing 12 kg, with a history of vomiting, apathy, nystagmus, ataxia and acute evolution hemiparesis. As a result of adoption, it was not known about the animal's morbid past. On special physical and clinical examination, depressed mental status, changes in postural reactions, nostril stenosis with unilateral mucopurulent nasal discharge, corneal ulcer, palpebral and labial ptosis, absence of eyelid reflex and spontaneous strabismus were observed, all of these findings observed on the left side of the face. No signs of otitis external to otoscopy were found. The clinical signs found characterize left facial nerve paresis and peripheral and central vestibulopathy. Otitis media / internal and meningoencephalitis were suspected. Hemogram, serum biochemistry (glucose, urea, creatinine, alanine aminotransferase, total proteins, albumin, globulin, alkaline phosphatase, gamma glutamyltransferase, phosphorus, total bilirubin, cholesterol and total calcium), urinalysis, rapid tests for erlichiosis, anaplasms , borreliosis, heartworm, distemper and leishmaniasis, CSF analysis, neurological panel performed by PCR (Polymerase Chain Reaction) that tested the animal for Bartonellosis, Lyme Disease (Borrelia burgdorferi), Blastomyces dermatitidis, Cryptococcus sp., Virus West Nile, Distemper, Toxoplasmosis, Neosporose and Coccidioides sp. using conjunctival swab, whole blood, urine and CSF samples. The samples were negative for all of these tests. As an image exam, brain magnetic resonance was performed. In the latter, otitis media and left internal was observed with extension of the lesion to the brain parenchyma. CSF analysis showed cytological changes compatible with a non-suppurative inflammatory process, mild pleocytosis with predominantly mononuclear leukocyte infiltrate. As a form of treatment, antibiotic therapy and total ablation of the auditory canal with lateral bulectomy were performed, showing good results with reduced clinical symptoms. Discussion: It is concluded that although the diagnosis of otitis media and internal with extension to brainstem is more common in cats, it should be included as a differential for central vestibular disorders in dogs, and that the diagnosis together with early and effective treatment are important, since that the evolution of the infection to the central nervous system represents a risk to the patient.

Pigeon as a model to study peripheral projections from the horizontal semicircular canal vestibular apparatus to a brainstem target immunoreactive for AMPA

ABSTRACT Purpose: To evaluate whether the pigeon (Columba livia) is a good model for evaluating the vestibular system involved with postural maintenance during movement. Methods: This study maps the brainstem targets of the horizontal ampullary inputs from the vestibular periphery of the pigeon. We used biotin dextran amine (BDA) injection in horizontal semicircular canal (HSCC), immunohistochemistry for GluR2/3 and GluR4 AMPA and computerized histomorphology reconstruction. Results: Our results show the same distribution pattern with ipsilateral projections to vestibular nuclear complex (VNC) from the HSCC, with the majority of labeled fibers being, long, thin, with few varicosities and many ramifications. Horizontal semicircular canal projections achieve neurons belonging to all nuclei of the VNC with exception of dorsal portion of lateral vestibular nucleus and this area express GluR2/3 and GluR4 AMPA receptors reinforcing the idea of glutamate participation in these connections. Conclusions: Pigeon is an appropriated experimental model to study of projections of HSCC and reinforcing the information that the vestibular system has strong relation with the fast responses necessary for postural control. Moreover, its phylogenetic organization apparently conservation, also seems to be a fundamental characteristic for vertebrates.

Brainstem auditory evoked potentials in horses / Potencial evocado auditivo de tronco encefálico em equinos

The brainstem auditory evoked potential (BAEP) evaluates the integrity of the auditory pathways to the brainstem. The aim of this study was to evoke BAEPs in 21 clinically normal horses. The animals were sedated with detomidine hydrochloride (0.013mg.kg-1 BW). Earphones were inserted and rarefaction clicks at 90 dB and noise masking at 40 dB were used. After performing the test, the latencies of waves (I, II, III, IV, and V) and interpeaks(I-III, III-V, and I-V) were identified. The mean latencies of the waves were as follows: wave I, 2.4 ms; wave II, 2.24 ms; wave III, 3.61ms; wave IV, 4.61ms; and wave V, 5.49ms. The mean latencies of the interpeaks were as follows: I-III, 1.37ms; III-V, 1.88ms; and I-V, 3.26ms. This is the first study using BAEPs in horses in Brazil, and the observed latencies will be used as normative data for the interpretation of tests performed on horses with changes related to auditory system or neurologic abnormalities.(AU)

O Potencial Evocado Auditivo de Tronco Encefálico (BAEP-Brainstem Auditory Evoked Potential) avalia a integridade das vias auditivas até o tronco encefálico. O objetivo da pesquisa foi padronizar o uso do BAEP em 21 equinos, sem aparente anormalidade auditiva. Os animais foram sedados com cloridrato de detomidina (0,013mg.kg-1 de PV). Foram utilizados fones de inserção,cliques de rarefação a 90 dB e um ruído de mascaramento de 40 dB. Foram identificadas as latências das ondas I, II, III, IV e V e dos interpicos I-III, III-V e I-V. As médias das latências das ondas foram: onda I 2,24ms; onda II 2,74ms; onda III 3,61ms; onda IV 4,61ms; e onda V 5,49ms. As médias das latências dos interpicos foram: I-III 1,37ms; III-V 1,88ms; e I-V 3,26ms. Este é o primeiro estudo utilizando o BAEP em equinos no Brasil e as latências observadas serão utilizadas como dados normativos para interpretação de exames de cavalos com anormalidades auditivas ou neurológicas.(AU)

Analysis of the brainstem internal morphology of the capuchin monkey (Cebus apella) / Análise da morfologia interna do tronco encefálico de macaco-prego (Cebus apella)

The gross anatomy and the internal morphology of the brainstem of the monkey Cebus apella were described based on the observations made on adult brainstens. Six adult Cebus apella monkeys were used for anatomical observations and for the study of the internal morphology they were cut into serial sections at six different levels (pyramidal decussation; superior portion of the olive; inferior portion of the olive; pons; superior colliculus and inferior colliculus) and properly stained for studies of the internal structure. Our results show that the Cebus apella brainstem is characterized by the presence of a bulbpontine sulcus; an enlarged brainstem, particularly of the medulla oblongata, with a consequent laterization of the trapezoid body, the presence of inferior olivary complex, the apparent origin of cranial nerves distant from the pyramids and of its decussation; presence of the antero-lateral sulcus separating the pyramids of the olives; expressive development of the trapezoid body, of the pons, nuclei of the pons and of the cerebral peduncle. These results are consistent with previous descriptions for other primates and suggest that the organization and development of the Brainstem structures share similarities with superior primates including humans which reflect the motor abilities of the studied species.(AU)

A anatomia e a morfologia interna do tronco encefálico (TE) do macaco-prego (Cebus apella) foram descritas com base nas observações feitas em troncos encefálicos de macacos adultos. Seis macacos Cebus apella adultos foram utilizados para as observações anatômicas. Para os estudos da morfologia interna os TE foram cortados seriadamente em seis níveis diferentes: decussação piramidal, porção superior da oliva, porção inferior da oliva, ponte, colículo superior e colículo inferior. Após esse procedimento eles foram corados com a técnica de Mulligan modificada por nós. Nossos resultados mostram que o TE de Cebus apella é caracterizado pela presença do sulco bulbo-pontino, aumento do tamanho do TE, especialmente da medula oblonga, com consequente lateralização do corpo trapezoide, presença do sulco ântero-lateral separando as pirâmides das olivas; desenvolvimento expressivo do corpo trapezoide, da ponte, dos núcleos da ponte e do pedúnculo cerebral. Estes resultados são consistentes com descrições prévias para outros primatas na literatura e sugerem que a organização e desenvolvimento do TE exibe semelhanças com primatas superiores, incluindo o homem, o que reflete as habilidades motoras da espécie estudada.(AU)