Fig. 6
From: Barrier dysfunction or drainage reduction: differentiating causes of CSF protein increase
Relationship between IgG quotient and albumin quotient as commonly shown in the Reiber diagram. a Blue circles show how isolated changes in barrier permeability shape the relation between IgG and albumin quotients, while the black solid line demonstrates the corresponding effect of isolated changes in CSF drainage rate. The albumin quotient of 0.002 is taken as the nominal value. Decrease in CSF drainage and increase in barrier permeability lead to increased IgG and albumin quotients, and vice versa. Quotient variations due to changes in barrier permeability are perfectly described by the hyperbolic function (Eq. 10) empirically derived by Reiber (red solid line, Rsquare = 1). In contrast, quotient variations due to changes in CSF drainage follow a linear trend. b Quotient variation due to barrier permeability change. The dashed line represents nominal CSF drainage conditions, while the upper and lower solid lines are representative of 30% increased and decreased CSF drainage rates, respectively. The population variation coefficient for albumin quotients of 0.001, 0.002, 0.003 is, respectively, 0.48, 0.44 and 0.4. c The effect of barrier permeability change for three different baseline IgG permeabilities. The dashed line represents the nominal IgG permeability and upper and lower solid lines represent 30% increased and decreased IgG baseline permeability, respectively. The calculated variation coefficient is constant (with a value of 0.6) for all albumin quotients