What imaging modalities are recommended for the diagnosis and staging of retinoblastoma in a primary care setting?

In a primary care setting, the initial diagnosis of retinoblastoma is primarily clinical, based on ophthalmic examination and referral rather than direct imaging. However, when imaging is required for diagnosis and staging, the recommended modalities are ultrasound and magnetic resonance imaging (MRI).

Ultrasound (ocular ultrasound) is often the first imaging modality used to detect intraocular calcifications characteristic of retinoblastoma, providing a rapid, non-invasive assessment suitable for initial evaluation. It is accessible and can help differentiate retinoblastoma from other intraocular lesions.

MRI is the preferred imaging modality for detailed staging, assessing the extent of the tumour within the eye, optic nerve involvement, and possible intracranial extension. MRI avoids ionising radiation, which is critical in paediatric patients, and provides superior soft tissue contrast to evaluate extraocular spread and intracranial structures.

Computed tomography (CT) is generally avoided in children due to radiation exposure but may be used if MRI is contraindicated or unavailable.

Therefore, in primary care, the role is to recognise clinical signs and promptly refer for specialist ophthalmic assessment, where ultrasound and MRI are employed for diagnosis and staging of retinoblastoma ¹ (Ray et al., 2012; Silvera et al., 2021; Ching et al., 2025).