• Specific patterns of metabolites by long echo time multislice proton nuclear magnetic resonance spectroscopic imaging [ Designated as safety issue: No ]
• Spectroscopic patterns associated with tumor progression, tumor necrosis, radiation necrosis, and tumor edema by conventional MRI [ Designated as safety issue: No ]
• Correlation of early metabolic changes with predictive response [ Designated as safety issue: No ]

• Specific patterns of metabolites by long echo time multislice proton nuclear magnetic resonance spectroscopic imaging
• Spectroscopic patterns associated with tumor progression, tumor necrosis, radiation necrosis, and tumor edema by conventional MRI
• Correlation of early metabolic changes with predictive response

RATIONALE: Imaging procedures such as MRI may improve the ability to determine the response of brain tumors to therapy.

PURPOSE: This clinical trial is studying how well MRI works in evaluating response to therapy in children with primary or metastatic brain tumors.

OBJECTIVES:

• Define specific patterns of metabolites using long echo time multislice proton nuclear magnetic resonance spectroscopic imaging.
• Attempt to distinguish spectroscopic patterns associated with tumor progression, tumor necrosis, radiation necrosis and tumor edema on conventional MRI imaging.
• Determine if early metabolic changes are predictive of response in children with brain tumors treated with chemotherapy.

OUTLINE: Patients undergo nuclear magnetic resonance spectroscopic (NMRS) imaging prior to therapy, immediately after the first cycle of therapy, and/or prior to subsequent cycles of therapy.

After NMRS imaging, all patients are injected with IV gadolinium-DTPA and postcontrast T1-weighted images are performed.

PROJECTED ACCRUAL: Approximately 50 patients will be accrued for this study.

• Drug: motexafin gadolinium
• Procedure: magnetic resonance spectroscopic imaging

DISEASE CHARACTERISTICS:

• Histologically confirmed primary or metastatic brain tumor
• Measurable or evaluable
• Brain stem glioma patients need no prior histological diagnosis
• Concurrent enrollment on a NIH primary brain tumor treatment trial or the Natural History or Standard Therapy protocols

PATIENT CHARACTERISTICS:

Age:

• 21 and under

Performance status:

• Not specified

Life expectancy:

• Not specified

Hematopoietic:

• Not specified

Hepatic:

• Not specified

Renal:

• Not specified

Cardiovascular:

• No cardiac pacemakers

Pulmonary:

• Not specified

Other:

• Not pregnant
• No neural implants, shrapnel, or cochlear implants
• No physical or psychological factors interfering with imaging studies
• No contraindications to anesthesia
• No history of severe reaction to gadolinium or other contrast agents

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• Concurrent chemotherapy allowed

Endocrine therapy:

• Concurrent immunotherapy allowed

Radiotherapy:

• Concurrent radiotherapy allowed

Surgery:

• No metallic implants (e.g., ferrous surgical clips)