Supplementary Material for: Orbital edema secondary to a sphenoidal mass as the presenting symptom of high-risk precursor B cell acute lymphoblastic leukemia: a case report

Introduction
Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy, known to present with ocular manifestations in rare cases.

Case presentation
We describe the case of a 9-year-old previously healthy male who developed a 2-day history of periocular swelling and was found on MRI to have a large sphenoidal mass. Further work up showed involvement of the spinal cord, iliac crests, and kidneys. His initial blood work showed no hematological abnormalities. A bone marrow biopsy taken from the iliac crest demonstrated >90% B lymphoblasts and flow cytometry was positive for CD19. Overall, his investigations were consistent with a diagnosis of precursor B cell ALL (pre B-ALL). His neuro-ophthalmic exam showed right sided subtle periocular edema, decreased palpebral fissure height, and proptosis. Posterior exam showed mild nasal elevation of the right optic disc without vessel obscuration and mild tortuosity of the peripheral vessels. He otherwise had no overt signs of afferent or efferent dysfunction despite the proximity of the mass to his optic nerve and globe.

Conclusion
This case demonstrates that high risk pre B-ALL, a childhood cancer not commonly associated with orbital manifestations, can present with orbital edema and normal leukocyte count in an otherwise healthy child.