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Cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) is a late onset neurodegenerative disorder. Its genetic basis has recently been identified in the gene encoding a subunit of the Replication Factor C (RFC1). We present the case of a 62-year-old woman who experienced a history of a biphasic presentation of imbalance and gait disorders, with rapid onset of symptoms followed by slow and progressive neurological deterioration. The diagnostic process was challenging, and numerous tests were conducted to rule out acquired and genetic causes of ataxia, leading to a diagnosis of late-onset idiopathic cerebellar ataxia. Subsequently, vestibular function tests identified severe bilateral vestibulopathy. This led to considering CANVAS among the diagnoses, which was ultimately confirmed through genetic testing (biallelic expansion of the pentanucleotide AAGGG in the RFC1 gene). This case highlights the importance of this new described genetic disease and its subacute presentation variant, emphasizing the relevance of objective vestibular function tests in idiopathic ataxias to achieve proper diagnosis and eventual genetic counseling for offspring.

El síndrome de ataxia cerebelosa, neuropatía y arreflexia vestibular (CANVAS) es un trastorno neurodegenerativo progresivo que se manifiesta en etapas tardías de la vida. Su base genética ha sido recientemente identificada en el gen que codifica la subunidad 1 del factor C de replicación (RFC1). Presentamos el caso de una mujer de 62 años con una historial de desequilibrio y deterioro de la marcha de presentación bifásica, con un inicio rápido de los síntomas seguido de un deterioro neurológico lento y progresivo. El proceso diagnóstico fue complejo y se realizaron numerosas pruebas para descartar causas adquiridas y genéticas de la ataxia, arribando al diagnóstico de ataxia cerebelosa de inicio tardío idiopática. Ulteriormente, las pruebas de función vestibular identificaron una grave vestibulopatía bilateral. Esto llevó a considerar el CANVAS entre los diagnósticos, que finalmente fue confirmado mediante pruebas genéticas (expansión bialélica del penta-nucleótido AAGGG en el gen RFC1). Este caso subraya la importancia de esta nueva enfermedad genética y su variante de presentación subaguda y enfatiza la relevancia de las pruebas objetivas de función vestibular en las ataxias consideradas idiopáticas para lograr un diagnóstico adecuado y un eventual asesoramiento genético a la descendencia.

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Abstract Introduction: Bilateral vestibulopathy is a rare chronic condition with multiple etiologies. Bilateral vestibulopathy is characterized mainly by unsteadiness when walking or standing, which worsens in darkness, as well as oscillopsia. The degree of handicap caused by bilateral vestibulopathy is variable and remains controversial. Objectives: To determine the value of the video Head Impulse Test in quantifying vestibular deficit and to establish its impact on the quality of life. Methods: Twenty patients (mean age, 41.9 years; range 14-80 years) fulfilling the recent Barany criteria of bilateral vestibulopathy, responded to the Situational Vertigo Questionnaire and underwent vestibular examination including fixation, positional tests, oculomotor test battery and video head impulse test. Results: The relation between each of the video head impulse test parameters and the scores from the questionnaire were statistically analyzed. We observed that patients with covert saccades on the video head impulse test were more likely to have a better quality of life than those with both covert and overt saccades, regardless of the vestibulo-ocular reflex gain in each semicircular canal. The presence of covert saccades was found to be associated with an improved quality of life regardless of the severity of vestibule ocular reflex-deficit. Our conclusion was that vestibule ocular reflex gain, measured by video head impulse test, does not quantify the severity of affection of quality of life in patients with bilateral vestibulopathy. Conclusion: Covert saccades are strategies aiming at minimizing the blurring of vision during head movement, that is an adaptive mechanism that improves quality of life. Therefore, we recommend that video head impulse test should be a part of the routine diagnostic workup of bilateral vestibulopathy.

Resumo Introdução: A vestibulopatia bilateral é uma condição crônica rara, com múltiplas etiologias. É caracterizada principalmente por instabilidade ao caminhar ou ficar de pé, que piora na escuridão, e oscilopsia. O grau de deficiência causado pela vestibulopatia bilateral é variável e permanece controverso. Objetivos: Determinar o valor do teste do impulso cefálico na quantificação do déficit vestibular e estabelecer seu impacto na qualidade de vida. Método: Vinte pacientes (média de 41,9 anos; variação de 14 a 80) que atendiam aos critérios recentes da Bárány Society de vestibulopatia bilateral responderam ao Situational Vertigo Questionnaire e foram submetidos a exame vestibular, inclusive fixação, testes posicionais, bateria de testes oculomotores e teste do impulso cefálico com vídeo. Resultados: A relação entre cada um dos parâmetros do teste do impulso cefálico com vídeo e os escores do questionário foram analisados estatisticamente. Observamos que pacientes com sacadas corretivas cobertas do tipo covert no teste de impulso cefálico com vídeo tinham maior probabilidade de ter melhor qualidade de vida do que aqueles com ambas sacadas corretivas cobertas e sacadas corretivas abertas do tipo overt, independentemente do ganho no reflexo vestíbulo-ocular em cada canal semicircular. Verificou-se que a presença de sacadas corretivas do tipo covert está associada a uma melhor qualidade de vida, independentemente da gravidade do déficit no reflexo vestibulo-ocular. Concluímos que o ganho no reflexo vestíbulo-ocular, medido pelo teste do impulso cefálico com vídeo, não quantifica a gravidade do comprometimento da qualidade de vida em pacientes com vestibulopatia bilateral. Conclusão: As sacadas corretivas do tipo covert são estratégias que visam minimizar o embaçamento da visão durante o movimento da cabeça, ou seja, um mecanismo adaptativo que melhora a qualidade de vida. Portanto, recomendamos que o teste do impulso cefálico com vídeo faça parte da rotina de diagnóstico da vestibulopatia bilateral.

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INTRODUCTION: Bilateral vestibulopathy is a rare chronic condition with multiple etiologies. Bilateral vestibulopathy is characterized mainly by unsteadiness when walking or standing, which worsens in darkness, as well as oscillopsia. The degree of handicap caused by bilateral vestibulopathy is variable and remains controversial. OBJECTIVES: To determine the value of the video Head Impulse Test in quantifying vestibular deficit and to establish its impact on the quality of life. METHODS: Twenty patients (mean age, 41.9 years; range 14-80 years) fulfilling the recent Barany criteria of bilateral vestibulopathy, responded to the Situational Vertigo Questionnaire and underwent vestibular examination including fixation, positional tests, oculomotor test battery and video head impulse test. RESULTS: The relation between each of the video head impulse test parameters and the scores from the questionnaire were statistically analyzed. We observed that patients with covert saccades on the video head impulse test were more likely to have a better quality of life than those with both covert and overt saccades, regardless of the vestibulo-ocular reflex gain in each semicircular canal. The presence of covert saccades was found to be associated with an improved quality of life regardless of the severity of vestibule ocular reflex-deficit. Our conclusion was that vestibule ocular reflex gain, measured by video head impulse test, does not quantify the severity of affection of quality of life in patients with bilateral vestibulopathy. CONCLUSION: Covert saccades are strategies aiming at minimizing the blurring of vision during head movement, that is an adaptive mechanism that improves quality of life. Therefore, we recommend that video head impulse test should be a part of the routine diagnostic workup of bilateral vestibulopathy.

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BACKGROUND: The cerebellar ataxia, neuropathy, and vestibular areflexia syndrome was initially described in the early 1990s as a late-onset slowly progressive condition. Its underlying genetic cause was recently mapped to the RFC1 gene, and additional reports have expanded on the phenotypic manifestations related to RFC1, although little is known about the pattern and extent of structural brain abnormalities in this condition. OBJECTIVE: The aim is to characterize the structural signature of brain damage in RFC1-related disorder, correlating the findings with clinical symptoms and normal brain RFC1 expression. METHODS: We recruited 22 individuals with molecular confirmation of RFC1 expansions and submitted them to high-resolution 3T magnetic resonance imaging scans. We performed multimodal analyses to assess separately cerebral and cerebellar abnormalities within gray and white matter (WM). The results were compared with a group of 22 age- and sex-matched controls. RESULTS: The mean age and disease duration of patients were 62.8 and 10.9 years, respectively. Ataxia, sensory neuronopathy, and vestibular areflexia were the most frequent manifestations, but parkinsonism and pyramidal signs were also noticed. We found that RFC1-related disorder is characterized by widespread and relatively symmetric cerebellar and basal ganglia atrophy. There is brainstem volumetric reduction along all its segments. Cerebral WM is also involved-mostly the corpus callosum and deep tracts, but cerebral cortical damage is rather restricted. CONCLUSION: This study adds new relevant insights into the pathophysiological mechanisms of RFC1-related disorder. It should no longer be considered a purely cerebellar and sensory pathway disorder. Basal ganglia and deep cerebral WM are additional targets of damage. © 2021 International Parkinson and Movement Disorder Society.

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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.

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La vestibulopatía bilateral es poco frecuente, se caracteriza principalmente por inestabilidad al caminar o al estar de pie, visión borrosa inducida por el movimiento u oscilopsia al caminar o al realizar movimientos rápidos de la cabeza o del cuerpo, empeoramiento de la estabilidad en la oscuridad o terrenos irregulares, reducción de los síntomas al estar en condiciones estáticas, ganancia del reflejo vestíbulo-ocular angular reducida de forma bilateral, entre otros. Existen múltiples causas. Dentro de las causas identificables, se describen principalmente medicamentos ototóxicos, meningitis y enfermedad de Ménière. Se presenta el caso de una paciente de 64 años diagnosticada con vestibulopatía bilateral posterior a tratamiento intramuscular con gentamicina por sobreinfección bacteriana cutánea de las manos. La evaluación vestibular complementada con videonistagmografía y prueba de impulso cefálico asistida por video confirman el diagnóstico y se inicia tratamiento con rehabilitación vestibular enfocada en promover la compensación central a través de estrategias de sustitución principalmente; además de habituación y adaptación vestibular, favoreciendo la estabilización de la mirada, mantención del equilibrio, control postural, marcha y reducción de los síntomas.

Bilateral vestibulopathy is infrequent, and it is characterized mostly by unstable walking or when standing, blurred vision induced by movement, or oscillopsia when walking or performing fast movements; worsening of the stability in darkness or uneven ground, but with lack of symptoms in static conditions. Other symptoms may include bilateral reduction of the oculo-vestibular reflex. Among the identifiable causes, there is the use of ototoxic medication, meningitis, Ménière's disease, although it can be idiopathic or have a neurological cause. We hereby describe the case of a 64-year-old woman, diagnosed with bilateral vestibulopathy secondary to intramuscular treatment with gentamicin due to a bacterial hand infection. Vestibular assessment was complemented with video-nystagmography and video head impulse test which confirmed the diagnosis, and therapy was started with vestibular rehabilitation focused on promoting central compensation mainly, through substitution strategies. Also, habituation exercise and vestibular adaptation strategies were used, thus promoting sight stabilization, balance maintenance, postural control, walking, and reduction of the symptoms.

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OBJECTIVES: CANVAS is an acronym for cerebellar ataxia, neuropathy and vestibular areflexia syndrome. Limited autopsy data has suggested that CANVAS is caused by a focal dorsal root ganglionopathy that damages Scarpa's (vestibular) ganglion, but spares the Spiral (hearing) ganglion. If the vestibular areflexia of CANVAS is in fact due to ganglionopathy, then there should be global reduction of all vestibular responses. MATERIALS AND METHODS: With this hypothesis in mind, a retrospective review of 5 subjects who met the clinical criteria for CANVAS was performed. Recent advances in vestibular testing have made it possible to quantify responses from all 5 vestibular end organs in the inner ear. Results of the Video head impulse test (VHIT), video oculography, caloric test and vestibular evoked myogenic potential (VEMP) were examined to determine if all 5 end organs are nonfunctional in CANVAS. RESULTS: Severe reduction of function of the six semicircular canals and ocular VEMPs were observed. Only the cervical VEMPs were present and reproducible, consistent with either partial sparing of the inferior vestibular ganglia, specific embryologic resistance of the saccule to the degeneration or a mechanism for cervical VEMPs that does not require an intact vestibular ganglion. CONCLUSION: Our results suggest that Scarpa´s ganglia dysfunction could be the mechanism for loss of semicircular canal and utricular function in CANVAS patients, but the preservation of the cervical VEMP response is unexplained.

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RESUMO Objetivo Avaliar a vertical visual subjetiva em indivíduos adultos jovens sem queixas vestibulares e/ou alterações do equilíbrio corporal. Método Estudo do tipo observacional, descritivo, analítico, de delineamento transversal, no qual foram avaliados 50 adultos jovens, com idade entre 18 e 30 anos. Foram excluídos do estudo indivíduos com alteração neurológica, alteração cognitiva evidente, deficiência física que influenciasse no equilíbrio corporal, alteração visual sem uso de lentes corretivas, uso de medicamentos com ação sobre o sistema nervoso central e/ou vestibular, relato de ingestão alcoólica 24 horas antes da avaliação e indivíduos com alterações e/ou queixas vestibulares. Os participantes foram submetidos à anamnese e à avaliação da vertical visual subjetiva, por meio do teste do balde. O teste foi realizado em três condições sensoriais diferentes: 1- Indivíduo sentado, com os dois pés sobre superfície estável (piso de paviflex); 2- Indivíduo sentado, com os pés em cima de uma espuma; 3- Indivíduo em pé sobre uma espuma. Resultados A vertical visual subjetiva não apresentou diferença significativa (p= 0,93) entre as condições sensoriais estudadas. Conclusão Em adultos jovens hígidos, o sistema proprioceptivo não influenciou significativamente a avaliação da vertical visual subjetiva, realizada por meio do teste do balde.

ABSTRACT Objective To evaluate subjective visual vertical in young adults without vestibular complaints and/or body balance problems. Methods This was a descriptive cross-sectional, observational and analytical study that assessed 50 young adults aged 18 to 30 years. Adult were excluded from the study if they had neurological and cognitive disorders, physical disability that affected their balance, visual impairment with no use of corrective lenses, use of drugs with effects on the central nervous system and/or the vestibular system and self-report of alcoholic use 24 hours before the assessment, and adults with vestibular problems and/or complaints The participants answered questions in a medical history interview and underwent subjective visual vertical assessment with the bucket method. The test was performed under three different sensory conditions: 1 - Subjects sitting with both feet on a stable surface (Paviflex® flooring); 2- Subjects sitting with their feet on top of foam; 3- Subjects on top of foam. Results The subjective visual vertical did not show a significant difference (p = 0.93) among the study sensory conditions. Conclusion The proprioceptive system did not significantly influence the measurement of the subjective visual vertical in young healthy adults.

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Introducción: el implante coclear (IC) se ha convertido en el tratamiento más efectivo para la hipoacusia neurosensorial severa-profunda. En los últimos años se han ampliado sus indicaciones, especialmente los casos bilaterales. Es por ello que en la comunidad otológica surge el interrogante de cómo puede afectar a la función vestibular la inserción de un array de electrodos intracocleares. Material y método: Estudio descriptivo, de tipo longitudinal, entre diciembre de 2013 y julio de 2016. Se realizó una revisión de 92 historias clínicas de pacientes que se sometieron a implante coclear en el mismo centro por el mismo equipo y cumplían criterios de inclusión. Resultados: De los 92 pacientes evaluados en el preoperatorio se observaron: Normofunción vestibular bilateral: 56 pacientes (60,8%), Hipofunción vestibular bilateral: 13 pacientes (14,1%), Hipofunción vestibular unilateral: 21 pacientes (22,8%). De los 46 oídos evaluados pre y post IC, un 14,8% (7 pacientes) presentaron hipofunción vestibular post IC, con normofunción previa. Solo 2 pacientes del total de la muestra presentaron sintomatología vestibular severa, con hipovalencias objetivadas en el post operatorio. Conclusiones: Se recomienda evaluar la función vestibular periférica en todos los pacientes candidatos a implante coclear, ya que de no existir otras consideraciones podría ser de utilidad a la hora de definir el lado a implantar.

Introduction: cochlear implant (IC) has become the most effective treatment for severe-deep neurosensory hearing loss. In recent years, indications have been extended, especially bilateral cases. This is why in the otological community the question arises as to how insertion of an array of intracochlear electrodes can affect the vestibular function. Material and method: A descriptive longitudinal study between december 2013 and july 2016. A review of 92 clinical records of patients who underwent cochlear implantation at the same center by the same team and met inclusion criteria were performed. Results: Of the 92 patients evaluated in the preoperative period, bilateral vestibular normobility: 56 patients (60.8%), bilateral vestibular hypofunction: 13 patients (14.1%), unilateral vestibular hypofunction: 21 patients (22.8%). Of the 46 ears assessed pre- and post-IC, 14.8% (7 patients) presented vestibular hypofunction post-IC, with previous normofunction. Only 2 patients from the total sample had severe vestibular symptoms, with postoperative hypovalences. Conclusions: It is recommended to evaluate the peripheral vestibular function in all patients candidates for cochlear implants since, if there were no other considerations, it might be useful to define the side to be implanted.

Introdução: el implante coclear (IC) se ha transformado no tratamento mais efectivo para a hipoacusia neurosensorial severa-profunda. Os últimos juros se han ampliado sus indicaciones, especialmente os casos bilaterais. É por isso que na comunidade otológica surge o interrogante de como pode afetar a função vestibular a inserção de uma matriz de eletrodos intracocleares. Material e método: Estudo descritivo, de tipo longitudinal, entre dezembro de 2013 e julho de 2016. Se realizou uma revisão de 92 historias clínicas de pacientes que se tornaram mais importantes um implante coclear em si mesmo por meio do mesmo e consideramos critérios de inclusão. Resultados: De los 92 pacientes avaliados no pré- operatório observado: Normofunção vestibular bilateral: 56 pacientes (60,8%), Hipofunção vestibular bilateral: 13 pacientes (14,1%), Hipofunção vestibular unilateral: 21 pacientes (22,8%). De los 46 oídos avaliados e pós IC, un 14,8% (7 pacientes) apresentaram hipofunção vestibular post IC, con normofunción previa. Solo 2 pacientes do total da amostra apresentaram sintomatologia vestibular severa, com hipovalencias objetivadas no pós-operatório. Conclusões: verificar a função vestibular periférica em todos os pacientes candidatos a implante coclear ya que não existe de outras formas consideradas poder ser de utilidade à hora de definir o lado a implantar.

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RESUMO Introdução A tontura na infância e adolescência interfere no comportamento psicológico e pode levar a consequências, como mau rendimento escolar e distúrbios de linguagem. Objetivo Desenvolver e verificar a aplicabilidade da versão reduzida do Dizziness Handicap Inventory-Child/Adolescent (DHI-CA) em crianças e adolescentes em fase escolar. Métodos Estudo metodológico de validação, desenvolvido nas unidades de ensino da rede pública municipal do Distrito Sanitário Cabula/Beiru de Salvador, Bahia. Os dados foram coletados por meio do Dizziness Handicap Inventory Child/Adolescent (DHI-CA) e da proposta reduzida, denominada Dizziness Handicap Inventory Child/Adolescent-short form (DHI-CA/SF). O DHI-CA/SF é composto de 15 questões objetivas, divididas em subescalas correspondentes aos aspectos emocionais, físicos e funcionais. Resultados A amostra foi composta por 97 crianças e adolescentes. Destas, 69 eram do sexo feminino (71,1%) e 28 (28,9%) eram do sexo masculino. A faixa etária esteve entre 7 e 15 anos, com média de 11 anos. A consistência interna referente à escala total foi de α=0,84 e α=0,66, para a subescala funcional, α=0,61 para a emocional e α=0,65 para a física. Quanto à concordância das duas aplicações do DHI-CA/SF, foi verificado que os coeficientes de correlação intraclasse, intraexaminadores, demonstraram concordância satisfatória e de satisfatória a excelente para os itens, na segunda aplicação. Os valores de concordância na segunda aplicação foram os seguintes: emocional: 0,70; funcional: 0,93 e física: 0,80. Conclusão A partir do Dizziness Handicap Inventory Child/Adolescent DHI-CA, foi possível obter uma versão reduzida, denominada Dizziness Handicap Inventory Child/Adolescent-short form (DHI/CA-SF), aplicável em crianças ou adolescentes com queixas de tontura.

ABSTRACT Introduction Dizziness during childhood and adolescence interferes with psychological behavior, and can lead to consequences such as poor academic performance and language disorders. Purpose To develop and verify the applicability of the short version of the Dizziness Handicap Inventory-Child/Adolescent (DHI-CA) in school-going children and adolescents. Methods A methodological validation study developed in municipal public network teaching units of Cabula Sanitary District/ Beiru de Salvador, Bahia. Data were collected by means of the Dizziness Handicap Inventory Child/Adolescent (DHI-CA) and proposed short version denominated Dizziness Handicap Inventory Child/Adolescent-short form (DHI-CA/SF). The DHI-CA/SF is composed of 15 objective questions divided into subscales corresponding to emotional, physical and functional aspects. Results The sample of 97 children and adolescents was composed of 69 girls (71.1%) and 28 (28.9%), boys. The age-range was from 7 to 15 years with mean age of 11 years. Internal consistency relative to the total scale was α=0.84; and α=0.66 for the functional; α=0.61, emotional, and α=0.65 for the physical subscale. Relative to agreement between the two applications of DHI-CA/SF, the authors verified that the intra-examiner intraclass correlation coefficients demonstrated satisfactory agreement, and satisfactory to excellent agreement for the items in the second application. Agreement values in the second application were: - emotional: 0.70; - Functional: 0.93, and Physical: 0.80. Conclusion By means of the Dizziness Handicap Inventory Child/Adolescent DHI-CA it was possible to obtain a short version denominated Dizziness Handicap Inventory Child/Adolescent-short form (DHI/CA-SF) applicable in children or adolescents with complaints of dizziness.

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