Sophie Teeuwen works as a student researcher at the Princess Máxima Center in addition to her Master's degree in Medicine at Erasmus University. She spent five months researching in the Neuro-Oncology Department under the supervision of pediatric oncologist Lisethe Meijer and Giorgio Porro, ophthalmologist at UMC Utrecht. Sophie investigated ‘the predictive value of acquired nystagmus for visual impairment in children with brain tumors’. Can wobbly eyes predict worsened vision in a child with a brain tumor?
Four questions for student talent Sophie Teeuwen
The first question: What is nystagmus?
‘Nystagmus is an eye movement disorder characterized by the rhythmic back and forth movement of the eyes. It is colloquially known as 'wobbly eyes'. Depending on the location of the braintumor, nystagmus can occur. There are five different types of nystagmus, depending on the direction of the nystagmus. Nystagmus may be present at the time the brain tumor is discovered, or it may develop later, as the tumor grows. Children with a brain tumor often develop vision problems. This can seriously affect their quality of life.’
What prompted your research at the Máxima Center?
‘When I started the research, it was still unknown whether the presence of nystagmus, and especially the different types, were related to vision problems in children with a brain tumor. Especially in younger children, vision problems are quite difficult to detect because they are less able to attend eye exams. If poor vision is not diagnosed in time, it can get worse and lead to low vision or even blindness.’
What conclusions can you draw from this study?
‘This is a retrospective cohort study: I looked at the existing data from a large group of children on this aspect. It shows that nystagmus is a significant predictor of moderate to poor vision. If a child develops nystagmus due to a brain tumor, there is a high probability that vision is or will be impaired. In particular, a certain type of nystagmus (horizontal and mixed, different directions) is predictive. In tumors near the optic nerves, pituitary gland, and hypothalamus (suprasellar), horizontal and mixed nystagmus are common and vision is impaired. The younger the child is when the brain tumor is diagnosed, and the earlier the damage to eye function occurs, the greater the impact on vision.’
What does this study mean for children with brain tumors?
‘The study shows that nystagmus can be used as a warning signal of poor vision. By starting therapy in time, further deterioration of vision can be prevented. This is expected to increase the chance of survival and prevent further decline in quality of life. It also works like this: nystagmus can be a signal that a space-occupying process is taking place in the brain, then the diagnosis with an MRI can be conclusive.’