Assessment of the Clinical Benefit of Imaging in Children With Unilateral Sensorineural Hearing Loss: A Systematic Review and Meta-analysis.

Key PointsQuestionWhat is the clinical benefit of diagnostic imaging (computed tomography [CT] or magnetic resonance imaging [MRI]) in children with isolated unexplained unilateral sensorineural hearing loss (USNHL)? FindingsIn this systematic review and meta-analysis, imaging revealed relevant pathophysiologic findings in one-third of 1504 children with USNHL, but these findings did not alter treatment for USNHL. Only detection of enlarged vestibular aqueduct with a pooled frequency of 7% for CT and 12% for MRI yielded information on hereditary factors and higher risk of progressive hearing loss in participants. Harms of imaging include radiation exposure in CT and sedation for MRI if MRI is performed in young children. MeaningImaging performed as part of the routine workup for patients with USNHL does not provide information that alters treatment or give insight into prognosis or hereditary factors of hearing loss in most cases; the benefits of imaging should be carefully balanced against the drawbacks during shared decision making. This systematic review and meta-analysis evaluates the diagnostic yield of computed tomography and MRI in children with unexplained sensorineural hearing loss to determine the clinical benefit of imaging. ImportanceImaging used to determine the cause of unilateral sensorineural hearing loss (USNHL) in children is often justified by the high likelihood of detecting abnormalities, which implies that these abnormalities are associated with hearing loss and that imaging has a positive contribution to patient outcome or well-being by providing information on the prognosis, hereditary factors, or cause of hearing loss. ObjectivesTo evaluate the diagnostic yield of computed tomography (CT) and magnetic resonance imaging (MRI) in children with isolated unexplained USNHL and investigate the clinical relevance of these findings. Evidence ReviewCochrane Library, Embase, PubMed, and Web of Science databases were searched for articles published from 1978 to 2017 on studies of children with USNHL who underwent CT and/or MRI of the temporal bone. Two authors (F.G.R. and E.N.B.P.) independently extracted information on population characteristics, imaging modality, and the prevalence of abnormalities and assessed the studies for risk of bias. Eligibility criteria included studies with 20 or more patients with USNHL who had CT and/or MRI scans, a population younger than 18 years, and those published in English. Main Outcomes and MeasuresThe pooled prevalence with 95% CI of inner ear abnormalities grouped according to finding and imaging modality. FindingsOf 1562 studies, 18 were included with a total of 1504 participants included in the analysis. Fifteen studies were consecutive case studies and 3 were retrospective cohort studies. The pooled diagnostic yield for pathophysiologic relevant findings in patients with unexplained USNHL was 37% for CT (95% CI, 25%-48%) and 35% for MRI (95% CI, 22%-49%). Cochleovestibular abnormalities were found with a pooled frequency of 19% for CT (95% CI, 14%-25%) and 16% for MRI (95% CI, 7%-25%). Cochlear nerve deficiency and associated cochlear aperture stenosis had a pooled frequency of 16% for MRI (95% CI, 3%-29%) and 44% for CT (95% CI, 36%-53%), respectively. Enlarged vestibular aqueduct (EVA) was detected with a pooled frequency of 7% for CT and 12% for MRI in children with USNHL. Conclusions and RelevanceImaging provided insight into the cause of hearing loss in a pooled frequency of about 35% to 37% in children with isolated unexplained USNHL. However, none of these findings had therapeutic consequences, and imaging provided information on prognosis and hereditary factors only in a small proportion of children, namely those with EVA. Thus, there is currently no convincing evidence supporting a strong recommendation for imaging in children who present with USNHL. The advantages of imaging should be carefully balanced against the drawbacks during shared decision making.