VHL and retinal hemangioblastoma: VHL is broadly divided into Type I and Type II and can be further subdivided based on the presence of hemangioblastoma and RCC. Type I VHL is associated with large deletion mutations resulting in decreased or no functionality in the encoded protein. Type I VHL is associated with CNS and retinal hemangioblastoma and RCC with a low risk of pheochromocytoma. Type II VHL is often associated with missense mutations resulting in an encoded protein with diminished functionality and results in a higher risk of pheochromocytoma [2].