In bringing forward this subject for your consideration, I intend to speak only of the three most frequent causes, which are, in the order of their importance, arterial diseases, embolism and spasm. I have not included thrombosis, except as it results from the above-mentioned cause, it being my belief that primary thrombosis in healthy unobstructed retinal arteries is rarely found, while as a complication of the above pathologic conditions it is rarely absent.
For many years following Graefe's publication in 1859, of the first carefully observed and recorded case of obstruction of the central artery by an embolus, most cases presenting a similar clinical history and picture were ascribed to this cause.
During later years, however, the increase in our knowledge of the histologic pathology of the retinal arteries has pointed to obliterating endarteritis and spasm as more common causes of the condition, and has thrown doubt on many
GREENWOOD A. OBSTRUCTIONS IN THE RETINAL ARTERIES.. JAMA. 1905;XLIV(10):781-782. doi:10.1001/jama.1905.92500370029001h