Retinoblastoma: What the Neuroradiologist Needs to Know

Abstract

Retinoblastoma is the most common primary intraocular tumor of childhood. Accurate diagnosis at an early stage is important to maximize patient survival, globe salvage, and visual acuity. Management of retinoblastoma is individualized based on the presenting clinical and imaging features of the tumor, and a multidisciplinary team is required to optimize patient outcomes. The neuroradiologist is a key member of the retinoblastoma care team and should be familiar with characteristic diagnostic and prognostic imaging features of this disease. Furthermore, with the adoption of intra-arterial chemotherapy as a standard of care option for globe salvage therapy in many centers, the interventional neuroradiologist may play an active role in retinoblastoma treatment. In this review, we discuss the clinical presentation of retinoblastoma, ophthalmic imaging modalities, neuroradiology imaging features, and current treatment options. ABBREVIATIONS: IACR etinoblastoma is the most common primary intraocular malignancy in children. Prompt diagnosis is essential to preserving life, eye, and sight. Neuroradiologists play an important role in diagnosis, staging, and treatment of patients with retinoblastoma. In this review, we aim to educate neuroradiologists regarding retinoblastoma imaging features and basic principles of treatment. EPIDEMIOLOGYRetinoblastoma affects 1 in 16,000 births, 1 with 8000-10,000 children diagnosed annually. There are no known geographic, racial, or sex predilections. Heritable retinoblastoma is diagnosed at a median age of 12 months and nonheritable disease at 24 months, with 80% diagnosed before 4 years of age. CLINICAL PRESENTATION AND DIAGNOSISRetinoblastoma is diagnosed by physical examination and classified as International Classification of Retinoblastoma groups A through E according to increasing severity. The most common

A descriptive neuroimaging study of retinoblastoma in children: magnetic resonance imaging features

“…MR images were evaluated in consensus by 2 subspecialty trained paediatric neuroimagers (AP, TAGMH) for the following features: 1) growth pattern (endophytic, exophytic, mixed); 2) intraocular extension (vitreous seeding/haemorrhage, retinal detachment and subretinal seeding/haemorrhage, anterior chamber involvement, choroidal invasion); 3) extraocular extension (scleral involvement, optic nerve involvement); 4) central nervous system disease (trilateral RB, leptomeningeal disease); 5) conventional MRI imaging characteristics of the RB lesions (T1 isointense, T2 isointense, FLAIR isointense, calcification, post-contrast enhancement); and 6) DWI and ADC characteristics [ 3 , 4 ].…”

“…A highly specific and sensitive diagnostic workup of local invasion is important to guide treatment and preserve vision if possible. Computed tomography (CT) has been used to define tumour calcification in the past, but because of the potential increased risk of secondary cancers due to exposure to ionizing radiation, especially in germline RB, the role of CT in the evaluation of RB is now historical and has been replaced by ultrasonography or MRI [ 3 ].…”

Magnetic resonance imaging of the orbit, Part 2: Characterization of orbital pathologies

“…More subtle findings such as enhancement at the globe-nerve junction can represent postlaminar tumor, pre- or intralaminar tumor with a posteriorly displaced lamina cribrosa, central retinal vessels, or inflammation. [ 9 ] Choroidal invasion appears primarily as an interruption or discontinuity of the normal chorioretinal outline on both T1 and T2 images with focal areas of increased enhancement or as thinning or loss of normal chorioretinal enhancement on postcontrast T1 images. More severe choroidal involvement may result in mass-like thickening.…”

“…An MR angiography (MRA) should also be part of the protocol to demonstrate variant arterial anatomy such as ophthalmic artery origins from the middle meningeal artery or dual arterial supply. [ 9 ] A new area of interest, termed radiogenomics, correlates tumor imaging characteristics with genetic alterations. [ 12 ] With more cumulative data, this method of radiophenotyping holds promise in aiding in early staging and treatment decision making in the future.…”

Contralateral catheterization of the ophthalmic artery to deliver intra-arterial chemotherapy in retinoblastoma

“…2 Currently, intra-arterial chemotherapy (IAC) is the first-line treatment in order to preserve the eye anatomically and functionally. 3,4 The aim of this technique is to superselectively catheterize the ophthalmic artery (OA) and deliver chemotherapeutic agents directly into the tumor. 5 The classic route to catheterize the OA is through the internal carotid artery (ICA), but other routes have been described.…”