Some Limitations of the Monro-Kellie Hypothesis

Dynamics of the cerebrospinal fluid and the spinal dura mater

“…Our current concepts of dural elasticity, however, remain influenced by the work of Weed and his co-workers, completed almost 40 years ago (Weed, 1929;Weed and Flexner, 1933;Weed, Flexner, and Clark, 1932). Although recognizing that the spinal dura mater has potential elasticity, they regarded the role of the venous system of the CNS as preeminent in providing for the elasticity of the CNS covering.…”

Pathophysiology and Treatment of Severe Traumatic Brain Injuries in Children

“…Based on the Monroe-Kellie hypothesis, the brain will initially attempt to compensate for the edema by displacing CSF into the spinal canal and venous blood into the jugular veins; however, if these mechanisms fail to decrease the volume within the cranial cavity, the ICP will increase (Weed, 1929). The cerebral edema can be monitored clinically through intracranial pressures, visualized on radiographic images, and observed through changes in the child’s behavior.…”

“…According to the Monro-Kellie hypothesis, ICP is relatively constant because the cranial cavity represents a fixed volume (Weed, 1929). If an increase in the volume of CSF, blood, or brain compartments occurs, the brain will compensate initially by displacing one of the two other compartments.…”

Pathophysiology and Treatment of Severe Traumatic Brain Injuries in Children

“…Hyperosmolar therapy with 3% hypertonic saline solution should be considered for intracranial hypertension because it alters cerebral volume (Weed, 1929). The effective acute dose of hypertonic saline is 6.5 to 10 mL/kg (milliliter per kilogram) and the continuous dose is 0.1 mL to 1.0 mL/kg/hr (milliliter per kilogram per hour) to maintain ICP < 20 mmHg (Kochanek et al, 2012).…”