[Differential diagnosis of vertical strabismus in the elderly].

Due to the demographic changes, the number of older patients in ophthalmological practices and clinics, including those with diplopia, is increasing. Some of the patients report not only horizontally shifted double images but also or only vertically shifted double images. Vertical double vision often causes significant diagnostic problems for ophthalmologists. The underlying condition could urgently require further neurological, neuroradiological and/or internal medical diagnostics (e.g., skew deviation, 4th nerve palsy, myasthenia, Graves' orbitopathy, orbital floor fracture, orbital mass, 3rd nerve palsy) but the cause of diplopia could also be a condition in which overdiagnosis should be avoided (e.g., sagging eye syndrome, the prevalence of which significantly increases with increasing age; decompensated strabismus due to inferior oblique muscle overaction, myopia-associated vertical tropia). For some diseases early diagnosis is important for a better prognosis, e.g., tumor diagnosis, Graves' disease and stroke. This article presents an overview of the most common and most important differential diagnoses of vertical tropia in patients over 50 years of age.