Retinoblastoma
Retinoblastoma is a rapidly developing cancer that occurs in the cells of the retina. It occurs in new born. It can happen unilaterally, or bilaterally. It can be inheritable, or non-heritable (can happen by chance). Symptoms can be a white reflex (instead of red) when taking photos. Depending on the position and size of the tumour, it may also cause a crossed eye, or, rarely, can affect the apparence of the eye externally; the internal changes at the retina can be detected with an Ophthalmoscope by an Optoemtrist or Ophthalmologist. When found, the priority is to preserve the life of the child, then, is to preserve vision. Radiation and surgical removal (enucleation of the eye) can be used. Nine out of ten of the children that has this can still develop into adulthood.
Choroidal Melanoma
By the name, melanoma is a type of cancer that occurs in the pigmented cell. It affects individuals with light skins and blue eyes. It can occur in the iris or the choroid behind the retina. Some melanomas are benign. They should be monitored in the case that they become malignant. An Optometrist can monitor the melanoma in a dilated fundus exam yearly.
See the ABCDE rule for malignancy test:
A: Atypical shape
B: undefined Border
C: Colouration
D: Diameter
E: Elevated (thickness)
Choroidal melanoma can also be metastasized from other origins in the body; the most common one is from liver.
The treatment of choroidal melanoma will depend on size and location of the tumour. Radiation is likely employed, and surgical removal (enucleation) of the eye would be the last resort.
Dr. Yan L. Liang, BSc OD
Markham Optometrist
www.wardenoptometry.ca