<prompt> There is a lesion in the orbit. Can you diagnose?Choroidal melanomaOcular retinoblastomaForeign body in the orbitOptic nerve drusen  <response>: Ans. A. Choroidal melanomaThe hyperintensity on T1 weighted MRI very specific for presence of melanin containing tumor in the orbit.The other causes of T1 hyperintensities are1. Blood products2. Proteinaceous substances3. Fat4. Gadolinium 