Synergistic Convergence in Horizontal Gaze Palsy With Progressive Scoliosis: A Case Report

This interventional case report documents the underlying genetic mutation, secondary muscle changes, and the result of surgical intervention in a patient presenting with synergistic convergence and esotropia. A 16-year-old patient underwent full ophthalmic examination, radiological imaging, and genetic testing. Diagnosis of horizontal gaze palsy with progressive scoliosis was confirmed, suggesting central miswiring as a cause of the synergistic convergence. Whole exome sequencing gene test revealed homozygous ROBO3 gene mutation (p.Leu888Arg) at a mutational hot spot with a GERP score of 4.88. Several computational analyses predicted the variant to be damaging. Bilateral medial rectus recessions of 7 and 8 mm were performed. Both medial rectus muscles were found tight, but not atrophic. Orthotropia and temporary resolution of synergistic convergence were documented. This case study reports a new mutation in the ROBO3 gene, and it is one of the few cases of central synergistic convergence that underwent surgical intervention and documenting secondary muscle changes.