Intraocular retinoblastoma presenting as ocular and orbital inflammation.

In the pediatric population, retinoblastoma must be included in the differential diagnosis of intraocular or orbital inflammation, especially if the case is atypical of unresponsive to medical therapy. Diffuse infiltrating retinoblastoma, a rare subtype of retinoblastoma, often presents as unilateral intraocular inflammation, usually occurs in older children, and may contain insufficient calcification for detection by CT scan. Orbital inflammatory signs may also be associated with intraocular retinoblastoma. The clinician must perform a thorough ocular examination in these cases with the suspicion of retinoblastoma. He or she must also understand the subtleties of noninvasive imaging in such cases. The goal is to diagnose this tumor more accurately and expediently so that treatment and counseling can be provided without delay.