Diffusely Increased Attenuation of the Subarachnoid Space

• Subarachnoid hemorrhage: May have enlarged ventricles and intraventricular blood.
• Cellular material: Pus, tuberculosis, sarcoid, cancer. May have enlarged ventricles.
• Intracranial hypotension: Dilated dural sinuses, normal-sized ventricles.
• Global anoxia: Diffuse loss of gray-white differentiation, white cerebellum sign, normal-sized ventricles.
• Contrast: From myelogram or intravenous contrast leakage in patients with renal failure.