• Vasogenic edema volume by MRI at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Lesion volume (contrast enhancement and necrotic core) by MRI at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Neurologic status, including mental status, cranial nerves, motor function, sensory function, reflexes, coordination, and gait at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Health-related quality of life by Short Form-36 Health Survey and General Well-Being Schedule at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Revascularization by perfusion MRI at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Survival every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Drop-out rate by steroid dosage at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Tumor progression by physical examination, positron emission tomography scans, and MRI at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Brain radionecrosis progression by MRI at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  
• Adverse events (e.g., events related to barotrauma and oxygen or steroid toxicity) at baseline, every 30 days during treatment, at the end of treatment, and then at 1, 2, and 4 months after treatment
  

OBJECTIVES:

• Obtain pilot data demonstrating the potential for increased benefit when complementing conventional steroid therapy with adjunctive hyperbaric oxygen therapy (HBOT) in patients with brain radionecrosis.
• Estimate the magnitude of benefit of HBOT using objective measures of neurologic function, radiographic imaging, and standardized quality of life measures in these patients.
• Determine, preliminarily, the effect of HBOT on cerebral revascularization using perfusion MRI in these patients.
• Determine the feasibility of performing a large-scale, randomized, controlled study (particularly with regard to patient recruitment and retention) comparing HBOT with conventional steroid therapy.

OUTLINE: This is a pilot, randomized, controlled study. Patients are randomized to 1 of 2 treatment arms.

• Arm I (conventional care only): Patients receive baseline steroid therapy comprising oral dexamethasone 4 times daily. Steroid doses are either increased or decreased per standard protocol during the 90-day treatment period. Patients who demonstrate neurological deterioration at each evaluation (as evidenced by a decrease in Karnofsky performance status score) receive escalating doses of dexamethasone until the maximum daily dose of 32 mg is reached. Patients who reach the maximum daily dose of dexamethasone are removed from the study. Patients also receive anticonvulsant therapy during study therapy.
• Arm II (conventional care and hyperbaric oxygen therapy [HBOT]): Patients receive conventional care as in arm I*. Patients also undergo HBOT once daily, 5 days a week, for 90 days (60 treatments total).

NOTE: *Patients in arm II who reach the maximum daily dose of dexamethasone are not removed from the study.

• Cerebral revascularization study: Five patients from each arm are randomly selected to undergo perfusion MRI before treatment and within 1 week after completion of study therapy to determine the proportion of cerebral neovascularization in each arm.

Patients are evaluated during study by standardized physical examinations, positron emission tomography scans, perfusion MRI, complete neurologic assessment, and standardized, health-related quality of life measures at baseline, at 30-day intervals during treatment, at the end of treatment, and at 1, 2, and 4 months after completion of study therapy.

After completion of study therapy, patients are followed at 1, 2, and 4 months.

PROJECTED ACCRUAL: A total of 30 patients will be accrued for this study.