1. Department of Ophthalmology, Vitreoretinal Section Zealand University Hospital Næstved Denmark
2. Department of Ophthalmology and Visual Sciences University of Iowa Hospital and Clinics Iowa USA
3. Scientific Unit Copenhagen Eye and Strabismus Clinic Copenhagen Denmark
4. Copenhagen Eye and Strabismus Clinic Copenhagen Denmark
5. Department of Ophthalmology, Strabismus Section Sahlgrenska University Hospital Gothenburg Sweden