Leukemic involvement of optic nerve.

We studied four cases of acute lymphoblastic leukemia with invasion of the optic discs and optic nerves. AII patients had central nervous system involvement. They received irradiation combined with intrathecal and systemic chemotherapy. The visual acuity improved in two cases, slightly improved in one case and did not improve in one case. However, fundoscopic examination showed clinical improvement after treatment in all cases. This combination therapy should be initiated on a semi-emergency basis in order to prevent irreversible visual loss in these patients.