On the Pressure Dependence of a Starling-Like Resistor.

Lakin, Stevens, and Thakore

A Starling resistor in models of fluid flow through a collapsible tube is a resistance term that depends on the transmural pressure across the tube wall. In a traditional Starling resistor, negative transmural pressure implies that the tube is fully collapsed and fluid flow is blocked. The present work develops a nonlinear expression for a Starling-like resistor that can be used to represent flow resistance in vessels, such as the intracranial transverse venous sinuses, where transmural pressure is negative in the normal resting state and the vessel is not fully collapsed. Expressing flow resistance in terms of vessel cross-sectional area, the lumped resistance between two points in the vasculature subjected to negative transmural pressure is found to depend on the transmural pressure at the downstream location. Applications to lumped-parameter models for idiopathic intracranial hypertension are discussed.