NATIONWIDE CHILDREN’S HOSPITAL
DEPARTMENT OF OPHTHALMOLOGY

PROGRESS REPORT

In 2010-2011 research efforts continued to concentrate on identifying sites within the brain responsible for the abnormal eye movements in patients with infantile nystagmus syndrome. Dr. Kashou in our group recently presented the results of this research at the 2011 annual meeting of the Association for
Research in Vision and Ophthalmology titled “Tractography of Infantile Nystagmus Syndrome”. This study utilized diffusion tensor imaging (DTI) to compare the number of white matter tracks for patients with infantile nystagmus syndrome compared with controls. Our group was the first to use these imaging techniques to assess the white matter tracks of patients with nystagmus. We found that a loss of fibers at the level of the Pons and Cerebellum could contribute to the involuntary ocular-motor dysfunction characterized by infantile nystagmus syndrome. We believe that further investigation of the cerebellumbrainstem-cerebrum connections using DTI will be crucial in identifying trouble regions in these pathways. We plan to continue our future research in this area.

Dr. Leguire collaborated with Dr. David Rogers in the Department of Ophthalmology at NCH to study different ways to measure visual acuity in children. Visual acuity is the smallest letters on the eye chart that can be correctly identified. It is very important to have reliable and accurate visual acuity data as this information plays a key role in the management of conditions such as amblyopia. Obviously, poor techniques in measuring visual acuity will lead to poor quality of data and potential mismanagement of the patient. Over a two day period at two different elementary schools, 334 children aged 8 to 11 years of age were tested using the EVA vision screening system. The children were divided into two groups, both of which were tested using the E-ETDRS protocol.

One group was given a card on which the 10 letters of the ETDRS chart were printed and were instructed only to choose from those letters (Forced choice group). The other group was tested with the standard E-ETDRS protocol (Standard group). We found that the visual acuity was significantly better in the Forced choice group for both eyes. We have prepared this data for presentation at the 2012 annual meeting of AAPOS and are developing the manuscript for publication.

Dr David Rogers and Dr. Leguire have also been working on ways to improve surgical outcomes in strabismus surgery. We undertook a quality improvement study designed to determine the accuracy of the calipers used during strabismus surgery. Our data revealed that the surgical calipers have surprising variability. Based on this information, we have modified our surgical techniques. We now verify the measurement on the surgical caliper against a ruler prior to using the instrument during surgery. This data is being prepared for both presentation at the 2012 AAPOS annual meeting and for publication.