Radiotherapy is the mainstay of treatment for brain malignancies and is associated with
significant neurotoxicity. Due to continuous increase in patient’s survival, the long term
risk for radiation-induced brain inflammation and necrosis inducing secondary cognitive
impairments are increasing concerns. Currently there is no effective treatment for preventing
long term radiation-induced brain damage.

Hyperbaric oxygen therapy (HBOT) is the administration of high oxygen concentrations within a
pressurized chamber to increase the cellular/mitochondrial delivery of oxygen. Oxygen
stimulation by HBOT has become the definitive therapy for radiation-induced damage to soft
tissues and bone due to its ability to stimulate healing processes by supplying the
energy/oxygen needed while down-regulating genes involved in inflammation. Oxygen stimulation
by HBOT is currently indicated for patients with overt radiation-induced neurotoxicity and
was proven to reduce further development of radiation damage while stimulating "idling"
neurons to return to function. Since HBOT is considered safe, we hypothesize that its
application following radiation, before the manifestation of neurological side effects, may
help avert development of early/delayed onset radiation-induced neurotoxicity.

In the proposed study, for the first time, HBOT will be applied early after radiation to
prevent the expected decrease in patients neurocognitive functions (NCF) and improve their
quality of life (QOL). The study is designed to provide statistically significant assessment,
in a prospective randomized clinical trial, of the effect of oxygen stimulation applied soon
after brain radiotherapy, for patients with primary and secondary brain tumors, on patients
QOL and NCF. In addition, advanced imaging methodologies will be applied to study the
feasibility of quantifying oxygen stimulation effects on the tumor and surrounding brain
tissue.