Once a child is suspected of having retinoblastoma, a complete eye and systemic examination is required.
Eye examination ~
The ophthalmologist who suspects retinoblastoma typically refers the child relatively urgently (within one or two days or a week) to a retinoblastoma expert. The retinoblastoma specialist evaluates the child’s medical and family history, examines parents and family members and then specifically focuses on the child’s eye examination. The eyes are checked with the pupils dilated. The doctor wears a headlight, called an indirect ophthalmoscope, and she/he uses a focusing lens to see all of the details in the back of the eye. It is generally necessary to restrain the child to steady the head and body so that a reliable examination can be performed. Numbing eyedrops are placed on the child’s eyes for comfort. The child’s eyelids are held open by a lid speculum and soft cotton applicators are used to gently rotate the eyes to allow maximal visualization of the back of the eye. This is generally not painful to the child, but the child may cry.
Systemic examination ~
The pediatric examination is performed by a pediatrician or a pediatric oncologist. The systemic examination is based on how the eyes appear and what treatment is needed. It might include:
• Physical examination
• CT or MRI of brain and orbits
• Blood tests
• Bone marrow analysis
• Hearing and kidney tests
If on chemotherapy, the hearing and brain tests are important. The brain CT and MRI are usually performed twice yearly until age 5 years. These tests are done to evaluate for possible spread of the tumor as well as other related cancers.
How do we know it is retinoblastoma ~
The diagnosis of retinoblastoma depends primarily on findings seen on eye examination. The child with retinoblastoma may be found to have a crossed eye or a white pupil by the parents or a pediatrician and then referred to an eye specialist for an eye examination. On examination, retinoblastoma has a classic chalky-white appearance with prominent blood vessels. It is rarely necessary to biopsy the tumor for confirmation.
To better assess the tumor, an examination with sedation of the child in the operating room, called an examination under anesthesia or EUA, is usually necessary. During EUA, a complete eye examination with a detailed drawing of all tumors and related findings is performed. Other confirmatory tests like photography, ultrasonography and fluorescein angiography are performed. These tests assist in planning the treatment strategy for the child. Fluorescein angiography uses an intravenous dye that discolors the child’s urine to a green-yellow color for one day.
If treatment is necessary, it is usually performed while the child is under anesthesia. Later, the doctors discuss the findings and treatment with the family. When the child recovers, the eyes might appear somewhat swollen and red for about 2 or 3 weeks. Future appointments are scheduled. If the child is in the midst of treatment, appointments are about 1 month apart. If the child is stable, then appointments are usually 2 to 6 months apart. Lifelong, all children with retinoblastoma should have an eye examination once or twice yearly.