Retinoblastoma spreads to CNS through:
a. Direct(Ref: Nelson's 20/e p 2476-2478, Ghai 8/e 614-615)Spread of Retinoblastoma:By direct extension to choroid; Along the optic nerve beyond lamina cribrosa to the CNS, orBy hematogenous or lymphatic spread to distant sites, including bones, bone marrow, and lungs.
Childhood Tumors
Direct
Lymphatic
Arterial
Vitreous
Direct