Acute lymphoblastic leukemia (ALL) is the most common
childhood leukaemia. It is a malignant neoplasm caused by the proliferation of
poorly differentiated precursors of the lymphoid cells. It is relatively
uncommon in adult. In adult ALL, central nervous system (CNS) involvement
is associated with poor prognosis. The incidence of CNS involvement has
been reported between 7% and 15 %. We report a case of optic nerve
infiltration in ALL in a 49 years old gentleman. He was diagnosed with
precursor-B ALL. He was treated with chemotherapy and CNS prophylactic
regime. He presented with sudden left eye loss of vision for one-day duration
with history of right eye inferior visual field loss for the past three months. His
visual acuity was no perception to light on the left eye and 6/9 on the right
eye. There was marked left relative afferent pupillary defect. The right eye
showed decreased in optic nerve function with inferior visual field defect.
Anterior segment examination was unremarkable in both eyes. Left optic disc
appeared normal but the right optic disc was pale. Blood investigation
showed no sign of infection or haemoconcentration. Cerebral spinal fluids
examination revealed abundant of white cells and blast cells. Magnetic
resonant imaging showed bilateral optic nerve enhancement suggesting of
bilateral optic nerves infiltration. He was started on a new regime of
chemotherapy followed by cranial radiotherapy. Unfortunately, he succumbed
to death due to septicaemia. There are variations in clinical presentation of
optic nerve infiltration in leukaemic patients. Normal appearance of optic disc
may not exclude the possibility of infiltration by malignancy. Assessment of
the optic nerve function and imaging is helpful for the detection of leukaemic
infiltration. Early detection of optic nerve infiltration is important for initiation or
change of therapy to prevent mortality.