Elevated Cerebrospinal Fluid Pressure Research Articles

Assessment of Objective Pulsatile Tinnitus in a Patient with Syringohydromyelia

We examined a 38-year-old male with syringohydromyelia and concomitant symptoms suggestive of intracranial hypertension including unilateral low-frequency sensorineural hearing loss and objective pulsatile tinnitus. The tinnitus was heard by the authors (through a hearing aid stethoscope tube), measured objectively (with a probe microphone), measured subjectively (as minimum masking levels and with fixed frequency Bekesy), and altered by changes in ear canal pressure (subjectively reported and measured objectively with a probe microphone). The audiologic symptoms were likely associated with elevated cerebrospinal fluid pressure that traveled to the cochlea through the cochlear aqueduct. The tinnitus may have originated from pulsations of central vascular structures that traveled through the cochlear aqueduct or the endolymphatic duct. Hearing loss likely resulted from tinnitus masking or a stiffening of the cochlear partition or stapes footplate.

Primary pseudotumor cerebri in association with obesity - a rare differential diagnosis even in childhood

Aims: Primary pseudotumor cerebri (PTC) is defined as elevated cerebrospinal fluid (CSF) pressure of more than 20cm H2O and exclusion of infectious, structural and systemic causes. Without treatment PTC can lead to loss of visual field and acuity. Case report 1: 13 year old, prepubescent, obese boy (BMI 33.5; 10>P97); since 10d headache and neck pain, vomiting; papilledema and loss of visual field. CSF pressure 80cm H2O. Exclusion of potential infectious, structural and systemic causes. Under treatment with acetazolamide, repeated lumbar puncture and gain of weight symptoms resolved. Case report 2: 15 year old, postpubertal, obese girl (BMI25; P97). Since one year intermittent headache, nausea; papilledema and slight affection of visual field. Intake of oral contraceptives. CSF pressure 37cm H2O. Exclusion of potential infectious, structural and systemic causes. Under treatment with acetazolamide symptoms resolved. Discussion: Elevated CSF pressure and exclusion of infectious, structural and systemic causes is called primary or idiopathic pseudotumor cerebri (PTC). In adults there is a strong association with obesity and a predilection for women. Contrary to adults obesity in association with PTC in childhood is reported to be uncommon. Structural and systemic causes play a stronger role like cranial venous outflow abnormalities (e.g. venous sinus thrombosis), medications, endocrine abnormalities, hypovitaminosis (vitamin A/D), anemias and autoimmune disorders. None the less our reported children show that non-typical patterns (1) or even less severe symptoms (2) in association with obesity should remind us of the differential diagnosis of PTC – especially on the background of the increasing incidence of obesity.

Ophthalmoparesis in Idiopathic Intracranial Hypertension

To report unusual ocular motility disturbances in the setting of idiopathic intracranial hypertension (IIH). Interventional case series. Two cases with IIH and unusual ophthalmopareses are reported. Two patients with confirmed IIH presented with headache, diplopia, and papilledema. The first patient had bilateral sixth nerve palsies and a partial right third nerve palsy, which resolved rapidly after a cerebro spinal fluid (CSF) shunting procedure; the second patient had alternating skew deviation and upbeat nystagmus. Both cases had normal brain magnetic resonance imaging (MRI) and magnetic resonance venography (MRV) and normal CSF contents, ruling out a secondary cause of intracranial hypertension. These exceptional vertical and horizontal ophthalmopareses in the setting of IIH may be related directly to very elevated CSF pressures and may be secondary to altered CSF flow in the posterior fossa.

The 58th Annual Meeting of the American Academy of Neurology San Diego, California April 1-8, 2006

The 58th Annual Meeting of the American Academy of Neurology San Diego, California April 1-8, 2006

The diagnosis and treatment of idiopathic normal pressure hydrocephalus

Idiopathic normal pressure hydrocephalus (INPH) is a syndrome that is characterized by gait impairment, cognitive decline and urinary incontinence, and is associated with ventriculomegaly in the absence of elevated cerebrospinal fluid (CSF) pressure. There is significant variation in the clinical presentation and progression of this disorder, and its diagnosis often represents a challenge for neurologists and neurosurgeons. Various supplemental tests, including the CSF tap test, external CSF drainage via spinal catheter, and CSF outflow resistance determination, can improve the accuracy of predicting a response to surgical treatment. CSF shunting provides significant symptom improvement in the majority of appropriately evaluated patients. In 2005, an international study group published evidence-based guidelines for the diagnosis and management of INPH. This review will highlight the clinical presentation, radiographic findings, supplemental prognostic tests, differential diagnosis, surgical treatment and outcomes of INPH.

Elevated cerebrospinal fluid pressure in patients with Alzheimer's disease

BackgroundAbnormalities in cerebrospinal fluid (CSF) production and turnover, seen in normal pressure hydrocephalus (NPH) and in Alzheimer's disease (AD), may be an important cause of amyloid retention in the brain and may relate the two diseases. There is a high incidence of AD pathology in patients being shunted for NPH, the AD-NPH syndrome. We now report elevated CSF pressure (CSFP), consistent with very early hydrocephalus, in a subset of AD patients enrolled in a clinical trial of chronic low-flow CSF drainage. Our objective was to determine the frequency of elevated CSFP in subjects meeting National Institutes of Neurological and Communicative Diseases and Stroke – Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria for AD, excluding those with signs of concomitant NPH.MethodsAD subjects by NINCDS-ADRDA criteria (n = 222), were screened by history, neurological examination, and radiographic imaging to exclude those with clinical or radiographic signs of NPH. As part of this exclusion process, opening CSFP was measured supine under general anesthesia during device implantation surgery at a controlled pCO2 of 40 Torr (40 mmHg).ResultsOf the 222 AD subjects 181 had pressure measurements recorded. Seven subjects (3.9%) enrolled in the study had CSFP of 220 mmH20 or greater, mean 249 ± 20 mmH20 which was significantly higher than 103 ± 47 mmH2O for the AD-only group. AD-NPH patients were significantly younger and significantly less demented on the Mattis Dementia Rating Scale (MDRS).ConclusionOf the AD subjects who were carefully screened to exclude those with clinical NPH, 4% had elevated CSFP. These subjects were presumed to have the AD-NPH syndrome and were withdrawn from the remainder of the study.

Pseudotumor cerebri as an important differential diagnosis of papilledema in children

Introduction: Primary pseudotumor cerebri (PTC) in childhood is a rare but important differential diagnosis in children presenting with papilledema. It is defined as elevated cerebrospinal fluid (CSF) pressure of more than 20 cm H 2O, normal CSF composition, and exclusion of underlying structural or systemic causes. Visual loss is a serious complication, which requires careful monitoring and management. Patients and methods: We conducted a retrospective chart review of 12 patients with primary PTC. The mean age at presentation was 8 2 12 years, and there was a male-to-female ratio of 7:5. The aim of this study was to investigate the clinical features of primary PTC in children, and to highlight the different treatment options in normalizing intracranial pressure in these patients. Results: In the majority of cases, children presented with headache. Four patients had no obvious symptoms and papilledema was found on routine eye examination. Obesity was uncommon and there was no distinct sex predilection. Acetazolamide was our drug of choice for the initial treatment. Furosemide and prednisone were used as second-line agents. Treatment was gradually decreased after resolution of the papilledema with exception of the two youngest children, who remained symptomatic. One child underwent ventricular–peritoneal shunting. Discussion: The treatment goals of PTC are the relief of symptoms, and preservation of visual function. Acetazolamide is an effective first-line method of lowering raised intracranial pressure. In our study group especially the young children were difficult to treat. This might indicate an age-related difference in the etiology of PTC. When medical treatment remains ineffective and visual function deteriorates, surgical treatment should be considered.

The Chiari Pseudotumor Cerebri Syndrome: Symptom Recurrence after Decompressive Surgery for Chiari Malformation Type I

Introduction: The etiology of Chiari malformation type I (CM1) as well as other anomalies associated with CM1 remains poorly defined. We have noted the presence of elevated CSF pressures with small ventricles, consistent with the pseudotumor cerebri (PTC) syndrome in a group of CM1 patients that did not respond over the long term to posterior fossa decompression. In order to better understand this association, we reviewed a series of CM1 patients treated by posterior fossa decompression to define the prevalence and nature of post-Chiari PTC. Methods: We performed a retrospective chart review of 192 patients diagnosed with CM1 and treated by posterior fossa decompression. Patients who failed to respond to surgery were evaluated by CINE MR flow studies to assess presence of CSF flow at the foramen magnum and then by lumbar puncture if flow was present. The diagnosis of Chiari PTC was defined by recurrence of Chiari-like symptoms after decompression, elevated lumbar CSF pressure in the absence of ventriculomegaly, and transient resolution of symptoms with large volume lumbar CSF drainage. Results: Thirty-six of 192 patients did not improve with surgical decompression. Fifteen of 36 operative CM1 patients (41.6%) were found to have Chiari PTC. The most frequent symptoms of CM1/PTC patients were head pain, body aches, and balance difficulties. Three patients also experienced visual complaints. The mean maximum lumbar CSF pressure documented in this cohort was 26 cm of water in adults and 25.3 in children. All patients received treatment for the CM1/PTC that culminated with CSF shunt placement in 14/15. Seven of 9 pediatric patients had significant symptom resolution while 6/6 adult patients remained variably symptomatic. Conclusion: CM1 and PTC co-exist in a surprising percentage of failed operative CM1 patients and present with a syndrome that is difficult to treat. The etiology of this association after Chiari decompression is unclear, though perhaps posterior fossa surgery in the setting of abnormal anatomy and potentially anomalous CSF flow dynamics contributes to CSF malabsorption and resultant or coexistant PTC.

Frequency and amplitude of elevation of cerebrospinal fluid resting pressure by the Valsalva maneuver

Background: Patients are referred to ophthalmologists to evaluate for papilledema when they are found to have elevated cerebrospinal fluid (CSF) pressure. However, some of these patients have no clinical history consistent with intracranial hypertension. We aimed to determine how often and how high patients with normal opening pressure could artificially elevate their CSF pressure to a pseudopathologic level by performing a Valsalva maneuver. Methods: We measured CSF pressure at rest and after a Valsalva maneuver in 15 consecutive normotensive patients referred for CSF analysis to determine the frequency and amplitude of elevation of pressure. Manometry was performed in the standard lateral decubitus position with legs and knees extended and abdomen relaxed and then again during a Valsalva maneuver with hip flexion and bearing down against a closed glottis. Results: All 15 normotensive patients elevated their CSF pressure to levels greater than 25 cm water. One patient reached a maximum pressure of 47 cm water. Interpretation: Artifactual elevation of CSF pressure may therefore occur frequently. Caution is advised before accepting a diagnosis of intracranial hypertension in those lacking this syndrome. These patients require repeat CSF pressure measurements to either verify or refute previous recordings.

Feasibility study of serial lumbar puncture and acetazolamide combination in the management of elevated cerebrospinal fluid pressure in AIDS patients with cryptococcal meningitis in Uganda

A feasibility study of serial lumbar puncture and acetazolamide combination in managing raised cerebrospinal fluid pressure was undertaken in 18 patients with AIDS and cryptococcal meningitis in Uganda. There were no adverse events related to the intervention and improvement in minimental status score, performance score, symptoms and a reduction in intracranial opening pressure were observed. This method is therefore feasible in AIDS-associated cryptococcal meningitis in a resource-poor setting given the observed safety and possible effectiveness, a larger study is warranted.

Medical and surgical management of idiopathic intracranial hypertension in pregnancy.

Idiopathic intracranial hypertension (IIH) is a syndrome of increased intracranial pressure without hydrocephalus or mass lesion with elevated cerebrospinal fluid (CSF) pressure but otherwise normal CSF composition. It has been found that pregnancy occurs in IIH patients at about the same rate as in the general population, that IIH can occur in any trimester of pregnancy, that patients have the same spontaneous abortion rate as the general population, and that the visual outcome is the same as for nonpregnant patients with IIH. Although it is also stated that pregnant patients with IIH should be managed and treated the same way as any other patient with IIH, the use of imaging and drug contraindications do make a difference between the two groups. The treatment has two major goals, which are to preserve vision and to improve symptoms. The medical therapy includes weight control, nonketotic diet, serial lumbar punctures, diuretics, steroids, and certain analgesics. When medical therapy fails, surgical procedures should be considered. The two main procedures are optic nerve sheath fenestration and lumboperitoneal shunt. Anesthetic considerations in the pregnant patient are an additional factor when surgeries are contemplated. It is also noted that therapeutic abortion to limit progression of disease is not indicated and that subsequent pregnancies do not increase the risk of recurrence.

Arteriovenous malformations presenting with papilloedema

Cerebral arteriovenous malformations (AVMs) are fairly common and the majority of paediatric patients with this condition also present with intracranial haemorrhage. Two patients who had an incidental finding of an AVM associated with papilloedema are described here. The first was a 13‐year‐old male who presented after an accidental kick to the eyes. Examination revealed bilateral papilloedema. He gave a 2‐year history of intermittent headache. Brain magnetic resonance imaging (MRI) showed an unruptured AVM in the temporal lobe. Lumbar puncture revealed elevated cerebrospinal fluid pressure. Visual acuity and visual fields were normal. He was treated with acetazolamide and improved within a few weeks. He subsequently underwent stereotactic radiosurgery to the AVM. He discontinued acetazolamide due to adverse side effects and there was no recurrence of headache and papilloedema. The second patient was a 14‐year‐old male who had polyarticular juvenile chronic arthritis and received low‐dose steroids and methotrexate. Bilateral papilloedema was discovered during routine ophthalmology surveillance and he was otherwise asymptomatic neurologically. Brain MRI revealed an AVM in the posterior fossa. He had three embolization procedures, which have resulted in significant reduction in lesion size. The papilloedema resolved completely after the first two procedures, and visual acuity and fields remained normal. Here, possible underlying mechanism of raised intracranial pressure and importance of visual assessment in those with AVMs and their management are discussed.

The effect of optic nerve sheath decompression on CSF dynamics in pseudotumour cerebri and related conditions.

The effect of optic nerve sheath decompression (ONSD) on cerebrospinal fluid (CSF) pressure and outflow resistance was studied in six patients who underwent the procedure (four unilateral, two bilateral) for papilloedema secondary to raised intracranial pressure. Four patients (all female, average age 29.3 years) had pseudotumour cerebri while two patients (one male 34 years, one female 24 years) had cryptococcal meningitis. All patients had pre- and postoperative CSF pressure measurements. Three patients had a preoperative CSF infusion study and all six had a postoperative study to measure CSF outflow resistance. Five of the six patients had elevated CSF pressure prior to ONSD and in all five the pressure was still significantly elevated after the procedure. In one symptomatic patient with papilloedema the pressure was normal pre- and post-ONSD (this patient was on acetazolamide). All three patients who tested pre-ONSD had an abnormal outflow resistance; in only one case did this become normal after the procedure, although this patient later required shunting for persistent intracranial hypertension. Clinically, only one of the six cases had a substantial relief of symptoms and signs despite persistently high CSF pressure and outflow resistance. The other five patients went on to shunting after intervals ranging from one week to 8 months. The preliminary conclusion was drawn that ONSD does not have any predictable beneficial effect on CSF pressure or outflow resistance. Copyright 1999 Harcourt Publishers Ltd.

Pseudotumor cerebri.

Pseudotumor cerebri (PTC) is a syndrome of increased intracranial pressure without hydrocephalus or mass lesion and with normal cerebrospinal fluid (CSF) composition. Although often considered to be "idiopathic," detailed investigation has revealed a high incidence of venous outflow abnormalities in PTC syndrome patients. The thought that elevated intracranial venous sinus pressure is a "universal mechanism" for PTC syndrome of varying etiologies has been called into question by a study indicating that the increased venous pressure in idiopathic PTC patients is caused by the elevated intracranial pressure and not the reverse, suggesting that "the chicken is the CSF pressure elevation and the egg is the venous sinus pressure elevation." Vitamin A toxicity may play a role in the pathogenesis of idiopathic PTC. The treatment of PTC has two major goals: the alleviation of symptoms and preservation of visual function. When medical therapy fails or when visual dysfunction deteriorates, surgical therapies for PTC should be considered. The two main procedures performed include lumboperitoneal shunt and optic nerve sheath fenestration. Because of the association of PTC with venous sinus hypertension, some authors are considering venous sinus stenting for refractory cases of PTC. It is still unclear if primary treatment of the observed venous stenosis benefits patients with idiopathic PTC. This should be no surprise, as it is not certain whether the stenoses are the cause or the result of idiopathic PTC.

Idiopathic intracranial hypertension: priapism of the brain?

It has long been recognized that a clinical syndrome similar to idiopathic intracranial hypertension can occur secondary to venous sinus obstruction with the elevation in sinus pressure causing a reversal in the pressure gradient across the arachnoid granulations and therefore elevated CSF pressure. There remains, however, a group of predominantly obese female patients with elevated CSF pressures who have either no apparent abnormality of venous outflow or a tapering, apparently extrinsic compression, of their dominant transverse sinuses on catheter venography. This suggests that venous collapse may be associated in some way with the cause of the elevated pressure but clearly something else must be initiating the pressure rise or a circular argument ensues. Elevated CSF pressure compresses the veins, which then elevates CSF pressure. However, collapse of the venous sinuses secondary to the elevated CSF pressure once initiated may exacerbate the condition. It has been suggested that the initiating event leading to the elevated pressures in the idiopathic group of patients may be caused by cerebral hyperaemia and cerebral dysautoregulation. Priapism is a condition of pathological elevation of venous pressure of the male genitalia in which there are two forms: (1) venous out flow obstruction and (2) hyperaemia due to a to loss of regulation of blood flow and secondary venous out flow compression. Review of the literature suggests the pathophysiology of idiopathic intracranial hypertension may be analogous to that of priapism.

Probable NPH in patients with clinical AD: further support for the AD-NPH syndrome and CSF circulatory failure

Clinical background To determine the incidence of elevated CSF pressure (CSFP) in patients with a clinical diagnosis of AD. Several studies have documented the coexistence of AD pathology in NPH patients at a rate greater than chance. There has been no corollary study addressing the incidence of NPH among patients with AD. We report elevated CSFP, consistent with NPH, in a small subset of AD patients (ADNPH) enrolled in an ongoing clinical trial of chronic lowflow CSF drainage, via a novel VP shunt, in AD.

Clinical features of late-onset pseudotumor cerebri fulfilling the modified dandy criteria.

To characterize the clinical features of patients with pseudotumor cerebri (PTC) fulfilling the Modified Dandy Criteria who were diagnosed at or after the age of 44 years. We reviewed the medical records between 1987 and 1999 of 14 patients at a single institution who were diagnosed as having PTC at 44 years of age or older according to the Modified Dandy Criteria: neurologic manifestations attributable to generalized increased intracranial pressure, elevated cerebrospinal fluid pressure with normal cerebrospinal fluid composition demonstrated by lumbar puncture, and normal or small ventricles demonstrated by neuroimaging. We documented presenting symptoms and signs, significant medical conditions, and visual field follow-up. There were nine women and five men. Nine patients (64%) were obese. Five patients (36%) were asymptomatic. None presented with headache alone. Four patients (29%) had an identifiable cause of intracranial hypertension, including two with transverse sinus thrombosis, one with severe chronic obstructive pulmonary disease and cor pulmonale, and one with corticosteroid withdrawal after prolonged administration. During a median follow-up of 2 years of 12 patients, visual fields remained stable in 8, improved in 3, and worsened in 1. In comparison with patients who have idiopathic intracranial hypertension, our small series of 14 patients diagnosed after the age of 44 years were more often men, were less often obese, were less symptomatic, and had identifiable causes of intracranial hypertension in a substantial minority (29%). The visual prognosis in this age group is generally good. Because the nonidiopathic causes of PTC would be overlooked by adhering to the Modified Dandy Criteria, we propose a modification that excludes patients who have dural venous sinus disease demonstrated on magnetic resonance imaging and those who may be exposed to medications or toxins or have systemic disorders that are known to increase intracranial pressure.

Always Get a CT Before LP

Always Get a CT Before LP

Idiopathic Intracranial Hypertension (Pseudotumor Cerebri)

Neurology| October 01 2001 Idiopathic Intracranial Hypertension (Pseudotumor Cerebri) AAP Grand Rounds (2001) 6 (4): 45. https://doi.org/10.1542/gr.6-4-45 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Idiopathic Intracranial Hypertension (Pseudotumor Cerebri). AAP Grand Rounds October 2001; 6 (4): 45. https://doi.org/10.1542/gr.6-4-45 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search nav search search input Search input auto suggest search filter All PublicationsAll JournalsAAP Grand RoundsPediatricsHospital PediatricsPediatrics In ReviewNeoReviewsAAP NewsAll AAP Sites Search Advanced Search Topics: pseudotumor cerebri Source: Salman MS, Kirkham FJ, MacGregor DL. Idiopathic “benign” intracranial hypertension: case series and review. J Child Neurol. 2001;16:465–470. Chronic, recurring headache is a common symptom in children, with an increasing prevalence in recent years variously estimated at 5 to 11%,1 which is most often due to migraine or tension. Idiopathic intracranial hypertension (IIH) is an uncommon cause which requires prompt diagnosis and appropriate management to prevent vision loss. The authors retrospectively reviewed the diagnosis and treatment of 32 patients with IIH from Toronto, Canada and London, UK aged 2 to 17.5 years. Twenty-three (72%) were female. The most common presenting symptoms were headache (91%), nausea and vomiting (56%), double vision (38%), and visual loss or blurring (25%). Signs at presentation included papilledema (97%), VIth cranial nerve palsy (31% unilateral, 9% bilateral), decreased visual acuity (29%), retinal hemorrhages (13%), and constricted visual fields (12%). Associated disorders in 19/32 included obesity in 48%, recent or recurrent otitis media (28%), upper respiratory tract infection (16%), sinusitis (13%), Addison’s disease and thyroiditis in 1 patient, and sudden withdrawal of cyproterone acetate for precocious puberty in 1. In all cases, CT or MRI excluded hydrocephalus, space-occupying lesion, and sinus venous thrombosis. All but one had an opening CSF pressure of >20 cm. None developed tonsillar herniation after lumbar puncture (LP). Treatments intended to alleviate symptoms and prevent visual loss included acetazolamide as first line treatment (44%), corticosteroids (short course) used for deteriorating visual loss or persistent headache (34%), lumboperitoneal shunt (25%), optic nerve fenestration (16%), and repeat LP (25%). Combination treatments were used in 40%. Four (13%) received no treatment. Four recovered after the first LP and never required further therapy. None of these therapies has been proven to be effective in randomized controlled trials. Idiopathic benign intracranial hypertension or pseudotumor cerebri is defined as an increase in intracranial pressure in the absence of a space-occupying lesion. In children, 90% of cases occur in the 5- to 15-year age range, and only 10% in infants and those under 5 years.2 In adults, the mean age at diagnosis is 28 years (range, 15–40).3 Neuroimaging to exclude a mass lesion, hydrocephalus, or venous thrombosis usually shows a normal or small ventricular system or, in young children, separated skull sutures. After excluding a surgical lesion, the diagnosis is confirmed by demonstrating elevated CSF pressure on LP. In some cases, CSF pressure may rise intermittently so a normal, single reading does not exclude the diagnosis. CSF analysis is normal or shows a mild pleocytosis. Because of the risk of tonsillar herniation during LP, patients with definite papilledema and/or retinal hemorrhages are probably best referred to a neurosurgeon or neurologist for LP. Known causes of IIH include recent or recurrent otitis media, venous sinus thrombosis, mastoiditis, hypervitaminosis A, recent administration of tetracycline or other antibiotic, and sudden withdrawal or prolonged use of steroids. To alleviate headache and prevent visual impairment, a normal CSF pressure must be maintained and confirmed by repeated... You do not currently have access to this content.

Pseudomigrânea com pleocitose liquórica: monitorização intermitente da pressão intracraniana. Relato de caso

Pseudomigraine with pleocytosis is a self-limited and rather benign disorder, characterized by recurrent bouts of migrainous headaches, associated to focal neurological symptoms and to cerebrospinal fluid abnormalities. We have submitted an individual with pseudomigraine to three lumbar punctures. The first and the third lumbar punctures, carried out during symptomatic periods, revealed a cerebrospinal fluid with aseptic lymphomonocytic pleocytosis, and an opening pressure of 400 and 440 mmH2O, respectively. The cerebrospinal fluid pressure measured during an asymptomatic period was normal (190 mmH20). Although the underlying mechanisms of this disorder remain elusive, there is some evidence that suggests an involvement of autoimmune mechanisms leading to a reduction of the cerebral blood flow, similar to that seen in the cortical spreading depression. In this report, we raise the possibility of a contributory role to be played by the elevated cerebrospinal fluid pressure on the pathophysiology of this disorder.