Headache in idiopathic intracranial hypertension. A CGRP-dependent head pain?

Headache is the most frequent and often the most severe symptom of idiopathic intracranial hypertension (IIH) clinical presentation, although pain characteristics are very variable among sufferers and the pain may even lack in some cases. Whatever the headache features, refractoriness to treatments, pain worsening in the recumbent position, and frequent awakenings with severe headache late in the night are the specific complains of such patients. However, a migraine or probable migraine headache, mostly with a chronic headache pattern, can be diagnosed in about 2/3 of the cases.

Dural sinus collapsibility, idiopathic intracranial hypertension, and the pathogenesis of chronic migraine.

Available evidences suggest that a number of known assumption on idiopathic intracranial hypertension (IIH) with or without papilledema might be discussed. These include (1) the primary pathogenetic role of an excessive dural sinus collapsibility in IIH, allowing a new relatively stable intracranial fluids pressure balance at higher values; (2) the non-mandatory role of papilledema for a definite diagnosis; (3) the possibly much higher prevalence of IIH without papilledema than currently considered; (4) the crucial role of the cerebral compliance exhaustion that precede the raise in intracranial pressure and that may already be pathologic in cases showing a moderately elevated opening pressure; (5) the role as "intracranial pressure sensor" played by the trigeminovascular innervation of dural sinuses and cortical bridge veins, which could represent a major source of CGRP and may explain the high comorbidity and the emerging causative link between IIHWOP and chronic migraine (CM). Accordingly, the control of intracranial pressure is to be considered a promising new therapeutic target in CM.

Pain cognition in migraine: from basic neurophysiology to a behavioral paradigm.

Most of the data in this review have been already reported by the authors in Neurological Science, but the goal of the present paper is to realize an integrated lecture of all the available data and look to the last achievements in pain cognition, with a special focus on migraine and chronic migraine. According to the proposed integrated perspective, migraine can be viewed as an adaptive behavioral response with evolutionistic advantages.

Starling resistors, autoregulation of cerebral perfusion and the pathogenesis of idiopathic intracranial hypertension.

Two critical functions for the control of intracranial fluids dynamics are carried on the venous side of the perfusion circuit: the first is the avoidance of cortical veins collapse during the physiological increases of cerebrospinal fluid (CSF) pressure in which they are immersed. The second, is the generation of an abrupt venous pressure drop at the confluence of the cortical veins with the dural sinuses that is required to allow a CSF outflow rate balanced with its production. There is evidence that both of these effects are ensured by a Starling resistor mechanism (a fluid dynamic construct that governs the flow in collapsible tubes exposed to variable external pressure) acting at the confluence of cortical veins in the dural sinus.