This trial studies how well dual energy computed tomography (DECT) works in imaging patients with solid organ cancer that has spread to the brain. Imaging techniques, such as DECT, may help find and diagnose tumor cells and find out how far the tumor cells have spread in the brain.

PRIMARY OBJECTIVES:

I. To optimize two major parameters of computed tomography (CT) imaging for optimal detection of intracranial metastatic lesions.

Ia. Virtual monochromatic image reconstruction. Ib. Contrast bolus timing. II. To measure the detection accuracy of CT compared to the diagnostic standard of care gadolinium-based "Gamma Knife (GK)" protocol magnetic resonance imaging (MRI).

OUTLINE:

Within 7 days before the standard Gamma Knife MRI, patients undergo DECT scan over 6 seconds at 1.5, 5, 10, and 20 minutes after receiving the contrast agent.

Inclusion Criteria:

• Adult patient with pathology-proven solid organ cancer

• MRI of the brain with contrast, positive for two or more metastatic lesions

  • One lesion with a single greatest diameter on contrast-enhanced MRI of 1 cm or greater

• Planned treatment with stereotactic radiosurgery

Exclusion Criteria:

• Known allergy to iodine-based contrast agents
• Patients with glomerular filtration rate (GFR) less than 30 or use of hemodialysis
• If prior nephrectomy, GFR less than 60
• Prior central nervous system malignancy
• Prior brain radiation
• Pregnant women are excluded