Longitudinal Investigation of Brain Blood Flow Changes in Neurosurgical Patients

Exclusion Criteria

• •Patients:
• •Unwilling or unable to co-operate with breathing maneuvers
• •Respiratory or cardiac limitations to breathing through a mask
• •Medical contra-indications to limited hypercapnia (high CO2 - 50 mmHg) or hypocapnia (low CO2 - 30 mmHg) (i.e., known increased intracerebral pressure, metabolic acidosis or alkalosis)
• •Standard contraindications for MRI scanning
• •Verbal confirmed pregnancy
• •Known multiple intracranial diseases
• •Presence of intracranial hemorrhage within the last 3 months
• •Symptomatic increased intracranial pressure
• •Healthy subjects:
• •Unwilling or unable to co-operate with breathing maneuvers
• •Respiratory or cardiac limitations to breathing through a mask
• •Medical contra-indications to limited hypercapnia (high CO2 - 50 mmHg) or hypocapnia (low CO2 - 30 mmHg) (i.e., known increased intracerebral pressure, metabolic acidosis or alkalosis)
• •Standard contraindications for MRI scanning
• •Verbal confirmed pregnancy
• •Anamnesticly a history of neurological disease or current neurological deficits.