@article {1573121, title = {Dark-adapted threshold and electroretinogram for diagnosis of Usher syndrome}, journal = {Doc Ophthalmol}, volume = {143}, number = {1}, year = {2021}, month = {2021 Aug}, pages = {39-51}, abstract = {PURPOSE: To determine the utility of ophthalmology evaluation, dark-adapted threshold, and full-field electroretinogram for early detection of Usher syndrome in young patients with bilateral sensorineural hearing loss. METHODS: We identified 39 patients with secure genetic diagnoses of Usher Syndrome. Visual acuity, spherical equivalent, fundus appearance, dark-adapted threshold, and full-field electroretinogram results were summarized and compared to those in a group of healthy controls with normal hearing. In those Usher patients with repeated measures, regression analysis was done to evaluate for change in visual acuity and dark-adapted threshold with age. Spherical equivalent and full-field electroretinogram responses from dark- and light-adapted eyes were evaluated as a function of age. RESULTS: The majority of initial visual acuity and spherical equivalent results were within normal limits for age. Visual acuity and dark-adapted threshold worsened significantly with age in Usher type 1 but not in Usher type 2. At initial test, full-field electroretinogram responses from dark- and light-adapted eyes were abnormal in 53\% of patients. Remarkably, nearly half of our patients (17\% of Usher type 1 and 30\% of Usher type 2) would have been missed by tests of retinal function alone if evaluated before age 10. CONCLUSIONS: Although there is an association of abnormal dark-adapted threshold and full-field electroretinogram at young ages in Usher patients, it appears that a small but important proportion of patients would not be detected by tests of retinal function alone. Thus, genetic testing is needed to secure a diagnosis of Usher syndrome.}, issn = {1573-2622}, doi = {10.1007/s10633-021-09818-y}, author = {Ambrosio, Lucia and Hansen, Ronald M and Moskowitz, Anne and Oza, Andrea and Barrett, Devon and Manganella, Juliana and Medina, Genevieve and Kawai, Kosuke and Fulton, Anne B and Kenna, Margaret} }