What Researchers Did
Researchers reviewed the medical records of four patients who experienced vision problems after receiving stereotactic radiosurgery for tumours near their optic nerves.
What They Found
Optic neuropathy, a condition affecting the optic nerve, developed in all four patients between 7 and 30 months after their gamma knife radiosurgery, causing an abrupt change in their vision. MRI scans showed swelling and enhancement of the affected visual pathways in three patients. While all patients received systemic corticosteroids, only one partially recovered, and hyperbaric oxygen therapy given to one patient did not lead to improvement.
Canadian Relevance
This study covers delayed radiation injury, which is a Health Canada-recognised indication for hyperbaric oxygen therapy. However, the study itself was not conducted in Canada and did not demonstrate a benefit from HBOT in this particular case.
Study Limitations
As a case report, this study is limited by its very small sample size of only four patients, which means its findings cannot be broadly generalized.