Description: There is an abnormal bilateral white reflex present in this patient known as bilateral leukoria (Fig 8.1).

Differential Diagnosis: The most detrimental and concerning diagnosis to rule out is retinoblastoma. Other diagnosis for leukocoria includes ocular conditions (congenital cataract, retinopathy of prematurity, coloboma) and infectious (toxocariasis) and vascular (Coats disease, persistent fetal vasculature) etiologies. Given the age of presentation and the ominous bilateral eye involvement, my index of suspicion for retinoblastoma is extremely high.

History: I would ask whether the patient has any family members with any eye conditions that presented in a similar manner. What was the child’s prenatal and birth history? Has there been any contact with dogs, specifically puppies?

Exam: I would perform a complete exam including full ocular examination, inspection of the iris, and inspection of the lens. Dilated fundus examination and anterior vitreous exam are also necessary. Retinoblastoma may be diagnosed by dilated indirect opthalmoscopy. Visualization of a chalky, white mass with friable consistency is pathognomonic for retinoblastoma.

Workup: A B-scan ultrasound would reveal any calcification in the tumor confirming the presence of a retinoblastoma. Computed tomography (CT) and magnetic resonance imaging (MRI) are warranted if bilateral disease with retinoblastoma is present and may also be useful to rule out Coats disease, since it does not have calcification. Referral to a pediatrician is warranted because retinoblastoma is a life-threatening disease. I would also send the child for genetic testing of the RB1 mutation to evaluate risk for secondary malignancies and familial risk.

Treatment: Treatment priorities in order are to preserve life, the globe, and vision. Chemoreduction is the mainstay treatment with systemic chemotherapy administered to shrink the tumors. Following tumor shrinkage, we may then apply focal laser therapy, which also enhances uptake of the chemotherapeutic agents via destruction of blood-brain barrier in the retina. Surgical enucleation is reserved for significant tumor burden not amenable to more conservative treatment.

Advice: Early detection of intraocular disease and genetic analysis are important for establishing long-term prognosis. The favorability of prognosis is based on the Reese-Ellsworth classification: grade 1 is a small solitary tumor or multiple tumors with none >4 DD, and grade 5 has the worst prognosis with massive tumor involving greater than half the retina and vitreous seeding. Greater than half of all patients in the United States present with advanced intraocular disease.

Follow-up: Initial follow-up weekly during the initial diagnosis and coordination with other specialties. As treatments are initiated, examinations every 4-8 weeks are appropriate to monitor for tumor regression. Recurrence is common, and consequently, these patients should follow up every 4-6 months once in remission. Patients with hereditary disease require long-term oncologic follow-up because of risk of secondary malignancies like osteosarcoma. As usual, treatment of refractive errors and amblyopia require the use of polycarbonate lenses for eye protection.