Standard treatment for glioblastomas includes radiation and chemotherapy with a drug called
temozolomide (Temodar); however, glioblastomas frequently develop resistance to standard
treatment and recur or progress. Glioblastomas are known to have decreased levels of oxygen
compared to normal tissues. There is evidence that these lower oxygen levels in glioblastomas
may contribute to their ability to resist treatment effects of radiation and chemotherapy. In
this study we will look to increase the oxygen concentration within the glioblastoma by
adding hyperbaric treatments (the experimental part of this study) to standard treatment with
radiation and temozolomide in order to see whether increasing the oxygen concentration within
the tumor increases the tumor-killing ability of standard radiation and chemotherapy.

In addition, the investigators are interested to evaluate the effect of this treatment
protocol on a person’s quality of life and level of stress, and, therefore, the investigators
will ask subjects to complete several brief questionnaires while they are on-study.