Pars plana vitrectomy was performed on a six-year-old boy with complete retinal detachment associated with a morning glory disc of his left eye. Perfluorodecalin was injected to unfold the retina. During surgery, perfluorodecalin leaked repeatedly under the retina. This case demonstrates that a retinal hole in tissues lying within the optic disc anomaly provides a communication for fluid and perfluorodecalin between the subretinal space and vitreous cavity resulting in a rhegmatogenous retinal detachment in the morning glory syndrome.