Idiopathic intracranial hypertension

The prevalence of polycystic ovary syndrome in women with idiopathic intracranial hypertension

Purpose. The purpose of this study is to re-evaluate whether the prevalence of polycystic ovary syndrome (PCOS) amongst women with idiopathic intracranial hypertension (IIH) is higher than in the general population using the NIH criteria. Methods. We included all consecutive women with IIH of child-bearing age seen at a hospital-based neuro-ophthalmology clinic between the years 2000-2005. All consenting women included in this study filled-out a screening questionnaire aimed at identifying women at risk for PCOS. The endocrinologist examined each patient suspect of PCOS as well as their biochemical results and diagnosed PCOS according to NIH criteria. The prevalence of PCOS in these women with IIH was compared with the reported prevalence of PCOS in the general population. Results. Out of 58 women with IIH who completed the study, definite PCOS was diagnosed in nine women (9/58; 15.5%). We found a significantly higher prevalence of PCOS using the NIH criteria among the IHH study group (15.5%, P = 0.001) compared to the general population (8.7%). Conclusions. The prevalence of PCOS is higher among patients with IHH, compared to the general population. We suggest a novel screening questionnaire to aid in the identification of women with IIH at risk for PCOS.

Idiopathic intracranial hypertension is not benign: a long-term outcome study

Idiopathic intracranial hypertension (IIH) primarily affects young obese females, and potentially causes visual loss and severe headache. The aim of this experiment is to examine relapse rate and long-term outcome in IIH patients. The methods involved in this experiment include a prospective controlled study of 18 newly diagnosed IIH patients followed for a mean observation period of 21.1 (±8.0) months. Treatment regime included diuretics, dietary recommendations and check-up visits at a dietician. Baseline and follow-up included neurological examination, detailed headache history and comprehensive neuro-ophthalmological examination, including fundus photography, Humphrey visual fields, and measurement of the retinal thickness (RT) and retinal nerve fiber layers (RNFL) by optical coherence tomography (OCT). Relapse was defined as recurrence of either: (1) papilledema or (2) symptoms and demonstrated raised ICP. The result of this experiment is that relapse was found in 28%. Visual function improved from baseline to follow-up and was generally favorable. In patients without relapse of papilledema RT and RNFL were significantly thinner than in healthy controls (p = 0.003 and 0.02), although atrophy was clinically detectable in only one patient. Headache was still present in 67% of the patients at follow-up. Headache was heterogenic and unrelated to relapse. After an initial reduction, weight increased again in the relapse group compared to reduced weight in the non-relapse group (p = 0.013). Thus, the conclusions drawn are that headache was persistent, difficult to classify, and equally represented in relapse and non-relapse patients. Headache was thus a poor marker of active disease. Relapse rate was high and clinically undetectable optic disc atrophy was discovered in apparently well treated IIH patients.

[Treatment and prognosis of idiopathic intracranial hypertension in children. Retrospective study (1995-2009) and literature review]

AIM

Idiopathic intracranial hypertension (IIH) may cause severe visual loss due to the optic nerve damage. Routine management involves mainly medical treatment. The aim of this study was to improve diagnosis and management of IIH in children.

METHODS

The medical records of all patients with definite IIH seen at the children's hospital of Toulouse between 1995 and 2009 were reviewed. Cases of secondary intracranial hypertension were included because they did not present any cerebral lesions and underwent a similar therapeutic approach. The clinical and ophthalmological data at the beginning and at the end of their treatment was collected.

RESULTS

Eighteen children were included in this study. The average age was 10 years and the sex-ratio was equal to 1. There were 3 cases of secondary idiopathic intracranial hypertension in this pediatric group. The main features encountered were headache (15 children) and diplopia (8 children). Abnormal neurological examination was found for 11 patients with abducens nerve paresis in 8 cases, rachialgia in 6 cases, and neurogenic pains (neuralgia, dysesthesia, paresthesia, hyperesthesia) in the other cases. Papilledema was noted in 16 patients. At the initial phase, loss of visual acuity was documented in 6 patients and altered visual field in nine patients. All patients had a medical treatment. When recurrence occurred, each new treatment was documented, for a total of 23 treatments analyzed. Lumbar puncture was the only treatment for 2 patients. In 16 cases, first-line treatment was acetazolamide and it was the second choice in 1 case, with an average dosage of 11.2mg/kg and a mean duration of 2.5 months (15 treatments could be analyzed). This treatment was effective in 11 cases out of 15. Steroids were the initial treatment in 4 cases and second-line treatment in 4 cases (after failed acetazolamide therapy). The dosage was 1.5-2mg/kg for a mean duration of 1.5 months (6 treatments could be analyzed). This treatment was effective in 5 patients out of 6. One patient had dual therapy. No surgical procedure was necessary in this pediatric cohort. Three patients presented relapses of IIH. The outcome was good with no residual visual impairment in the 13 patients analyzed. One patient was still under medication.

COMMENTS

Therapeutic management of IIH in a pediatric population is essentially medical, in some cases limited to lumbar puncture. The first-line treatment is acetazolamide, but this study shows that low doses and short duration are usually chosen. Doses must be increased and treatment prolonged to avoid the use of corticosteroids as a second-line treatment and prevent possible relapses that require close monitoring of visual function.

CONCLUSION

The visual prognosis is generally better for this age group compared to adults and no risk factors for visual sequelae were identified. A standardized protocol for management of IIH was proposed.

Lumboperitoneal shunt for idiopathic intracranial hypertension: patients' selection and outcome

Surgical treatment of idiopathic intracranial hypertension (IIH) includes cerebrospinal fluid (CSF) diversion procedures most commonly lumboperitoneal (LP) shunt. LP shunt addresses the cause of both headache and papilledema more directly by effecting a global reduction of intracranial pressure. Twenty-two cases were included in the study. All patients underwent clinical, imaging, and CSF manometry evaluations. All patients showed failure or noncompliance to medical treatment and necessitated placement of an LP shunt. Analysis of data was conducted and evaluation of outcome was assessed. Among 22 patients who underwent LP shunt placement for IIH, 16 (72.8%) patients had severe and fulminant opening CSF pressures with values of more than 400 mmH(2)O. Among this group, 19 (86.4%) patients reported recovery of their headache and 16 (72.7%) patients showed complete resolution of papilledema. Shunt complications included two (9%) cases of shunt infection that required shunt extraction and antibiotic therapy, and six (27%) cases of shunt obstruction that required shunt revision. Manometric predictors for surgical treatment of IIH may include severe and fulminant opening CSF pressures as well as poor manometric response to repeated lumbar taps. Lumboperitoneal shunt is easy and effective for treating intractable headaches and visual impairment associated with IIH. Its usefulness can be optimized by meticulous technical placement of the shunt guided by rigorous protocols for shunt procedures.

Continuous intracranial pressure monitoring in pseudotumour cerebri: Single centre experience

OBJECTIVE

Investigating pseudotumour cerebri (PTC) patients who do not fulfil the diagnostic criteria, or those presenting post-shunt insertion with recurrent symptoms and signs, with no clear evidence of shunt malfunction, present a diagnostic challenge. PTC patients who underwent continuous intracranial pressure (ICP) monitoring in our unit were reviewed retrospectively.

RESULTS

Twenty-six ICP monitoring procedures were done on 20 patients. Eleven patients had normal pressure, 2 overdrainage/low pressure, 11 underdrainage/high pressure and 2 variable pressures. On the basis of these results 12 patients were managed conservatively: 11 patients were referred to headache team and 1 patient had readjustment of an adjustable valve shunt setting; of those 3 patients had improved symptoms on their first post-operative clinic review. On the other hand, 14 patients had surgery: 5 had shunt revision and 9 had shunt insertion; of those 5 patients improved.

CONCLUSION

ICP monitoring using an intraparenchymal probe is a safe and effective diagnostic technique in investigating PTC when indicated. A multidisciplinary approach achieves best results in terms of successful management and follow-up.

Idiopathic intracranial hypertension in the USA: the role of obesity in establishing prevalence and healthcare costs

This study documents for the first time the extraordinary costs to take care of patients with a chronic, non-fatal, relatively rare disorder who have been incorrectly thought to have an insignificant and self-limiting illness. Idiopathic intracranial hypertension (IIH) occurs worldwide and in all racial groups and is found predominantly in obese women (∼ 90%) of childbearing age. Although the incidence of IIH is increasing as a result of the rapid increase in obesity, the disorder in general receives little recognition, and no recognition of the extensive burden of healthcare costs placed on patients, their families and society. We established for the first time both the prevalence of IIH in the USA and the direct and indirect costs of IIH using a prevalence-based model. IIH patients had an exceptionally high hospital admission rate of 38% (in 2007), a partial reflection of unsatisfactory treatment options. The total hospital costs per IIH admission in 2007 were four times greater than for a population-based per person admission. Total economic costs of IIH patients exceeded $444 million. Programmes designed to reduce obesity prior to and after diagnosis and better therapeutics will have a tremendous economic impact.

MR imaging findings in patients with secondary intracranial hypertension

BACKGROUND AND PURPOSE

IH can alter the configuration of anatomic structures of the central nervous system. We determined the sensitivity and specificity of MR imaging to detect these changes in patients with secondary IH.

MATERIALS AND METHODS

Patients (n = 36) with IH were prospectively investigated with MR imaging and were matched to 36 controls. MR images were evaluated for elongation and edema of the optic nerves, protrusion of the optic disc, flattening of the posterior sclera, height of the pituitary gland, and width of the optic nerve sheath. On MRV, we recorded venous sinus abnormalities and measured the luminal width of the superior ophthalmic veins. A grading score was introduced to define cranial venous outflow obstruction.

RESULTS

Cranial venous outflow obstruction and ONS hydrops were the most valid signs indicating IH with a sensitivity of 94% and 92% and a specificity of 100% and 89%, respectively. Sensitivities and specificities were 56% and 97% for reduced pituitary height, 64% and 78% for flattening of the posterior sclera, 31% and 97% for widening of the superior ophthalmic veins, 33% and 100% for optic disc protrusion, 14% and 100% for optic nerve edema, and 6% and 100% for elongation of the optic nerve. At least 2 MR imaging findings could be demonstrated in each patient but in none of the controls. The number of positive MR imaging findings correlated with CSF pressure (r = 0.62, P = .01).

CONCLUSIONS

The combination of cranial and orbital MR imaging and MRV can be highly sensitive and specific in the diagnosis of patients with IH.

The entire dural sinus tree is compressed in patients with idiopathic intracranial hypertension: a longitudinal, volumetric magnetic resonance imaging study

INTRODUCTION

The objective of this study was to explore the volumetric alterations of dural sinuses in patients with idiopathic intracranial hypertension (IIH).

METHODS

Standardized cranial magnetic resonance imaging (MRI) was used in 17 patients prior to and following treatment of IIH and in seven controls. Magnetic resonance venographies (MRV) were employed for (a) judgement of circumscript dural sinus stenoses and (b) computation of sinus volumes. Cross-sectional areas (CSA) of the superior sagittal sinuses (SSS) were measured on T2-weighted images. Results of the initial MRIs were compared to those on follow-up MRIs and to results of controls.

RESULTS

Stenoses of the transverse sinuses (TS) resulting in cranial venous outflow obstruction (CVOO) were present in 15/17 (88%) patients, normalizing in 7/15 cases (47%) after treatment of IIH. CVOO was not detected in the control group. Segmentation of MRV revealed decreased dural sinus volumes in patients with IIH as compared to controls (P = 0.018). Sinus volumes increased significantly with normalization of intracranial pressure independent from disappearing of TS stenoses (P = 0.007). The CSA of the SSS were normal on the initial MRIs of patients with IIH and increased on follow-up after treatment (P < 0.001). However, volumetries displayed overlap in patients and controls.

CONCLUSIONS

Patients with IIH not only exhibit bilateral stenoses of the TS as has been reported, but volume changes of their entire dural sinus system also occur. The potential etiopathological and diagnostic roles of these changes are discussed.

Pseudotumor cerebri

INTRODUCTION

Pseudotumor cerebri is a condition characterized by raised intracranial pressure, normal CSF contents, and normal brain with normal or small ventricles on imaging studies. It affects predominantly obese women of childbearing age; however, its incidence seems to be increasing among adolescent and children. While among older children the clinical picture is similar to that of adults, younger children present demographic and clinical peculiarities. Different diagnostic criteria for adults and pre-pubertal children have been proposed. Etiology and pathogenesis are still unclear, particular concerning the role of obstruction to venous outflow.

METHODS

An extensive literature review concerning all the aspects of pseudotumor cerebri has been performed, both among adults and pre-pubertal children.

CONCLUSION

Pseudotumor cerebri is an avoidable cause of visual loss, both in adults and children. Few diagnostic measures are usually sufficient to determine the correct diagnosis. Since pseudotumor cerebri is a diagnosis of exclusion, the differential diagnosis work out is of special importance. Modern neuroimaging techniques, especially magnetic resonance imaging and magnetic resonance venography may clarify the role of obstruction to venous outflow in each case. Various therapeutic options are available: medical, surgical, and endovascular procedures may be used to prevent irreversible visual loss. Treatment is usually effective, and most patients will experience complete resolution of symptoms without persistent deficits.

Bariatric surgery for the treatment of idiopathic intracranial hypertension

Object

The purpose of this study was to review the literature on the effectiveness of bariatric surgery for obese patients with idiopathic intracranial hypertension (IIH) with regard to both symptom resolution and resolution of visual deficits.

Methods

The published literature was reviewed using manual and electronic search techniques. Data from each relevant manuscript were gathered, analyzed, and compared. These included demographic data, pre- and postoperative symptoms, pre- and postoperative visual field deficits, bariatric procedure type, absolute weight loss, changes in body mass index, and changes in CSF opening pressure.

Results

Eleven relevant publications (including 6 individual case reports) were found, reporting on a total of 62 patients. The Roux-en-Y gastric bypass was the most common bariatric procedure performed. Fifty-six (92%) of 61 patients with recorded postoperative clinical history had resolution of their presenting IIH symptoms following bariatric surgery. Thirty-four (97%) of 35 patients who had undergone pre- and postoperative funduscopy were found to have resolution of papilledema postoperatively. Eleven (92%) of 12 patients who had undergone pre- and postoperative formal visual field testing had complete or nearly complete resolution of visual field deficits, and the remaining patient had stabilization of previously progressive vision loss. In 13 patients both pre- and postoperative CSF pressures were recorded, with an average postoperative pressure decrease of 254 mm H2O. Changes in weight loss and body mass index varied depending on the reported postoperative follow-up interval.

Conclusions

The published Class IV evidence suggests that bariatric surgery may be an effective treatment for IIH in obese patients, both in terms of symptom resolution and visual outcome. Prospective, controlled studies are necessary for better elucidation of its role.

Idiopathic intracranial hypertension in children: a review and algorithm

This updated review of pediatric idiopathic intracranial hypertension focuses on epidemiology, clinical presentations, diagnostic criteria, evaluation, clinical course, and treatment. General guidelines for the clinical management of idiopathic intracranial hypertension are discussed. A new algorithm outlines an efficient management strategy for the initial diagnostic evaluation of children with signs or symptoms of intracranial hypertension. This algorithm provides a systematic approach to initial evaluation and management, and identifies important decision-making factors. The risk of permanent visual loss with idiopathic intracranial hypertension necessitates a prompt, thorough collaborative approach in the management of patients. Although idiopathic intracranial hypertension has been recognized for over a century, the need remains for prospectively collected data to promote a better understanding of the etiology, risk factors, evaluative methods, and effective treatments for children with this syndrome.

"Idiopathic" intracranial hypertension caused by venous sinus thrombosis associated with contraceptive usage

BACKGROUND

Cerebral venous sinus thrombosis (CVST) is a life-threatening condition that may present with symptoms and signs identical to idiopathic intracranial hypertension (IIH). Both conditions consist of increased intracranial pressure (ICP); however, IIH shows no evidence of contributory intracranial pathology. Oral hormonally based contraceptive usage has been associated with both conditions as well. Because disc edema often occurs in CVST, and IIH and is evident in other sight- and life-threatening conditions such as intracranial mass lesions, neuroimaging and other ancillary testing must be conducted for definitive diagnosis.

CASE

An 18-year-old white woman with IIH previously diagnosed presented with headaches and severe visual loss in the left eye. Bilateral disc edema with macular edema in the left eye (O.S.) was present. Threshold perimetry found bilaterally enlarged blind spots as well as a central scotoma O.S. Her medical history was significant for a right transverse, sigmoid and jugular siphon thrombosis secondary to a hypercoagulable state and associated with her use of oral birth control medication. Subsequent magnetic resonance venography (MRV) found the presence of CVST. Despite anticoagulation therapy and acetazolamide, she had severe, nonresolving papilledema. Treatment with oral prednisone was initiated. She recovered full visual fields and excellent visual acuity.

CONCLUSION

Because of the similarity in clinical presentation of CVST and IIH, it is important to differentiate distinguishing characteristics of these diseases for correct diagnosis and prompt treatment.

Endoscopic orbital roof fenestration as an alternative treatment option for idiopathic intracranial hypertension: a cadaveric anatomical study

BACKGROUND

We investigated a new minimally invasive surgical technique for the treatment of idiopathic intracranial hypertension in a cadaveric model. This technique aims at establishing a communication between the intraorbital and intracranial compartments by creating a bone, dural, and periorbital window in the anterior cranial fossa. This procedure is predicated on intraorbital absorptive capability that has been demonstrated in animals and discussed in humans.

METHODS

Three fresh cadaver heads were fixed in a head holder so as to mimic the hyperextended supine position. The procedure was conducted bilaterally in each specimen. Our technique is as follows: 1) An incision is made in the eyebrow medial to the supraorbital notch; 2) using an endoscope and a periosteal elevator, the intraorbital surface of the orbital roof is separated from the periorbita in an anteroposterior direction for a length of 1.5-2.5 cm; 3) a 1 cm of the exposed orbital roof is removed, and the dura and arachnoid are opened; and 4) slits are made in the exposed periorbita.

RESULTS

We were able to create a communication between the intracranial and the intraorbital compartments in all specimens.

CONCLUSION

Our technique is new and does not require any foreign body implantation. Its applicability in humans needs to be evaluated in a clinical context.

Detection of nerve fiber atrophy in apparently effectively treated papilledema in idiopathic intracranial hypertension

BACKGROUND

Since papilledema in idiopathic intracranial hypertension is a passive event not primarily affecting the visual tract, resolution with restitution ad integrum is expected if intracranial pressure is rebalanced. Retinal nerve fiber swelling due to papilledema in the acute phase and possible axon loss after long-lasting elevated intracranial pressure was investigated in a controlled cross-sectional study by scanning laser polarimetry.

METHODS

A cohort of 23 patients with idiopathic intracranial hypertension according to the modified Dandy diagnostic criteria, and 23 controls matched for age and gender were investigated. All patients received neurological and ophthalmologic examination including scanning laser polarimetry (GDx VCC). Patients were divided into groups depending on the presence of a papilledema (group 1) or the regression of the papilledema after initiation of therapy (group 2). Therapy was based on recommendations of the German Society of Neurology.

RESULTS

Scanning laser polarimetry showed an increase of nerve fiber thickness in group 1, and a decrease of the nerve fiber thickness in group 2 compared to controls. Ten of 13 patients showed signs of a regional axon loss in the deviation map of the GDx report, and six had a Nerve Fiber Index above 30. All patients with regressive papilledema and coincidence of visual field damage and pale optic disc appearance had a pathologic result in the GDx examination, but only four of ten patients with a pathologic GDx examination showed coincidence of pale optic disc appearance and visual field damage as sign of underlying optic disc atrophy.

CONCLUSION

In patients with apparently effective treatment of clinical symptoms and a regression of papilledema in idiopathic intracranial hypertension, a retinal axon loss was detected by scanning laser polarimetry. Axon loss was even present in patients without clinical evidence of optic nerve atrophy.

The anatomical basis of venographic filling defects of the transverse sinus

Obstruction of the intracranial dural venous sinuses would result in an increase in intracranial dural venous pressure. This intracranial hypertension is not only the result of poor cerebral venous drainage but also life threatening. The aim of this study was to identify the structures, which may show signs of potential venographic filling defect qualities, including trabeculae/septa (also described as "fibrous bands") and arachnoid granulations, which ultimately can lead to increased intracranial dural sinus venous pressure. A total of 102 cadavers and living patients were used for the study. Fifty-three percent of the subjects presented with structures in their transverse sinuses that could be potential venous filling defects. Thirty percent of the subjects presented with arachnoid granulations in the right transverse sinus, which were found to be significantly dominant (Chi-square; p < 0.05). The study also revealed the presence of 1 to 5 septa in 29.4% of the subjects. The septa were found to be more dominant in the central (30%) and lateral (22%) thirds of the right transverse sinuses, while the central third of the left transverse sinus proved to be the least dominant occurring site (8%). In general, the right transverse sinus is highly more significantly dominant in septal occurrence (Chi-square; p < 0.01) than the left transverse sinus. We conclude from the statistical evidence that the right transverse sinus demonstrates significantly more potential venographic filling defects than the left sinus and submit that this information may assist in management options for patients diagnosed with idiopathic intracranial hypertension as well as direct future research.

Venous obstruction and jugular valve insufficiency in idiopathic intracranial hypertension

The pathophysiology of elevated intracranial pressure in idiopathic intracranial hypertension (IIH) is unclear. Cerebral venous outflow obstruction and elevated intracranial venous pressure may play an etiological role. We examined jugular valve insufficiency as a potential factor contributing to intracranial hypertension. Jugular venous valve function was assessed bilaterally by duplex sonography in 20 consecutive patients with diagnosis of IIH and in 20 healthy controls matched for age, gender and body mass index. Diagnosis of valvular insufficiency was based on reflux duration during a controlled Valsalva maneuver. Intracranial venous outflow was evaluated in 11 patients (MR venography in 10, digital subtraction angiography (DSA) in two cases). As a principle result, valvular insufficiency was significantly more frequent in patients with IIH (70 vs. 30%; p < 0.05). This finding was associated with irregular leaflet structures on B-mode imaging (p < 0.01). Bilateral insufficiency was more frequent in the patient group which, however, was not significant (p = 0.08). In addition, sinovenous outflow obstruction was found in five of six patients that had undergone contrast-enhanced MR venography and DSA. The detection rate was inferior in phase-contrast MR imaging (one of five patients). In conclusion, this study gives evidence that valvular insufficiency may play a causal role in IIH. Obesity is a major risk factor for the disease and weight reduction leads to improvement of symptoms. Possibly, increased intra-abdominal pressure is transmitted into the intracranial venous system, causing intracranial hypertension. Jugular valve insufficiency may facilitate pressure transmission. As transverse sinus stenosis was a concomitant finding, these factors may be complementary.

A mathematical model of idiopathic intracranial hypertension incorporating increased arterial inflow and variable venous outflow collapsibility

Object

A collapsible segment in the venous outflow has been noted in many patients with idiopathic intracranial hypertension (IIH). Mathematical modeling has shown that these collapsible segments can account for the elevated cerebrospinal fluid (CSF) pressures associated with IIH. However, the model required an elevated outflow resistance of up to 10 times normal to predict the CSF pressures actually found clinically. Measurement of blood flow in patients with IIH has shown that inflow rates vary, with higher rates noted in patients with lesser outflow stenoses. The aim of this work was to extend a simple model of cerebral hydrodynamics to accommodate a collapsible sinus and elevations in cerebral blood flow in accordance with in vivo measurements.

Methods

Forty patients with IIH underwent MR imaging in which the degree of stenosis on MR venography was compared with the total blood inflow by using MR flow quantification. The relative outflow resistance in IIH was estimated using the CSF opening pressure. The patients were compared with 14 age-matched control individuals.

Results

Patients were divided into 3 groups based on MR venography appearances (minimal stenosis, stenosis of 40–70% and > 70% stenosis). In vivo measurements suggested a relative resistance elevation of 2.5 times normal, 4.2 times normal, and 4.8 times normal in the 3 groups, respectively. There was an increased inflow of 1.56 times normal, 1.28 times normal, and 1.19 times normal in these groups.

Conclusions

The model correctly predicted the CSF pressures noted in vivo, suggesting that high arterial inflow is required for patients with low-grade stenoses to be symptomatic.

Lumbar subcutaneous shunt: a novel technique for therapeutic decision making in normal pressure hydrocephalus (NPH) and benign intracranial hypertension (BIH)

Selecting patients who will benefit from a permanent CSF diversion procedure in benign intracranial hypertension (BIH) or communicating hydrocephalus due to normal pressure hydrocephalus (NPH) has inherent problems. The percutaneous introduction of a lumbar subcutaneous shunt (LSS) under local anaesthesia facilitates both a prolonged CSF drainage under aseptic conditions and also elicits an adequate clinical response. We describe the technique of a lumbar subcutaneous shunt and our experience with its use in patients with BIH and NPH. Postprocedure changes in the patients' clinical status were noted. Patients with a transient clinical improvement underwent a subsequent definitive CSF diversion; those with a sustained clinical improvement or no change in symptoms had no further procedure.

A comparison of idiopathic intracranial hypertension with and without papilledema

OBJECTIVE

To compare clinical features, visual characteristics, and treatment of idiopathic intracranial hypertension patients with and without papilledema.

BACKGROUND

Idiopathic intracranial hypertension does not often occur without papilledema. This study estimates the prevalence and compares the clinical characteristics of idiopathic intracranial hypertension patients with and without papilledema.

METHODS

We performed a cross-sectional analysis of all idiopathic intracranial hypertension patients diagnosed at the University of Utah Neuro-Ophthalmology Unit between 1990 and 2003. Patient records were reviewed for presence of papilledema and other signs, symptoms, and treatment characteristics. Each patient without papilledema was matched to the patient with papilledema who was closest to his/her age and sex. McNemar's and Wilcoxon-signed rank sum tests were used to compare characteristics between matched pairs.

RESULTS

Among all patients (n = 353), the prevalence of those without papilledema was 5.7% (n = 20). Patients without papilledema reported photopsias (20%), and were found to have spontaneous venous pulsations (75%) and non-physiologic visual field constriction (20%) more often than did those with papilledema. Mean opening pressure, although above normal, was lower in patients without papilledema (mean = 309 mm cerebrospinal fluid) compared with those with papilledema (mean = 373 mm cerebrospinal fluid, P = .031). Idiopathic intracranial hypertension patients without papilledema had more frequent diagnostic lumbar punctures than did patients with papilledema. Visual acuities and treatment were similar between groups.

CONCLUSIONS

The clinical presentation of idiopathic intracranial hypertension without papilledema is only somewhat different from that of idiopathic intracranial hypertension with papilledema. The lower opening pressure in patients without papilledema may explain variations in symptoms and signs between the 2 groups. When there are visual field changes in idiopathic intracranial hypertension without papilledema, non-physiologic visual loss should be considered.

Idiopathic intracranial hypertension after 40 years of age: clinical features in 23 patients

PURPOSE

Idiopathic intracranial hypertension (IIH) is a well-recognized disorder of unknown etiology associated with elevated intracranial pressure (ICP), normal neuroimaging, and normal cerebrospinal fluid (CSF) composition, found mostly among obese females of childbearing age. The aim of this study is to investigate the clinical features of IIH in patients older than 40 years.

METHODS

This is a retrospective chart review (1998-2007) of all consecutive patients older than 40 years who were diagnosed with IIH based on the Modified Dandy Criteria.

RESULTS

Twenty three of the 200 IIH patients in the institutional database fulfilled study entry criteria. They included 22 females and one male whose mean age was 51.4 years (range 41-79). Coexisting systemic arterial hypertension was found in 13 (56.5%) patients. Seventeen patients (73.9%) had symptoms attributable to elevated ICP. The most common presenting symptoms were visual; mainly blurred vision and transient visual obscuration (15/17 patients, 88.23%). Eleven patients (64.7%) complained of headache, and another 4 (23.5%) of pulsatile intracranial noise. The average follow up period was 21.8 months.

CONCLUSIONS

The findings indicate that IIH among individuals older than 40 years of age may be underreported. These patients are more likely to present with systemic hypertension and with more visual disturbances, but with fewer complaints of headache than the younger IIH population.

Commentary on clinical review: the surgical treatment of idiopathic pseudotumour cerebri, by Paul Brazis

Dr Brazis has written a review of the literature on the clinical manifestations of idiopathic intracranial hypertension, possible associated venous hypertension and intracranial dural venous sinus abnormalities, and a brief discussion of medical and surgical therapies. The preferred terminology for this condition is idiopathic intracranial hypertension, but pseudotumour cerebri is so engrained in the literature that it stubbornly remains (1). The manuscript covers the literature well, and the information reviewed serves as an excellent reference source for interested readers. Unfortunately, Dr Brazis has noted the conflicting expert opinions regarding success, failure and complications for each of the surgical procedures, and, as a result, his summary discussion is barren of any algorithm of management, or even recommendations in approaching these difficult patients.

[Surgical treatment of benign intracranial hypertension: optic nerve sheath fenestration]

Optic nerve sheath fenestration (ONSF) is rarely used in France. The aim of surgery is to release pressure around the optic nerve. Although debated, ONSF can be used in selected cases of benign intracranial hypertension. The authors describe the approach of the anterior part of the optic nerve and the technique itself. The indications, results and potential complications of this technique are developed in this paper.

Laparoscopic-assisted lumboperitoneal shunt placement for idiopathic intracranial hypertension

Lumboperitoneal (LP) shunting is considered an effective method of cerebrospinal fluid (CSF) diversion in patients with idiopathic intracranial hypertension (IIH). Confirmation of flow out of the distal portion of the catheter once in its final position can be difficult, especially in obese individuals. A new technique to improve placement of the peritoneal catheter involves laparoscopic catheter insertion. We performed laparoscopic-assisted LP shunt placement for IIH on four patients. Improvement in preoperative IIH symptomatology was noted in all patients. No laparoscopic-procedure-related complications were noted. No problems were noted in shunt functioning and none of the shunts have required revision surgery at last follow-up. LP shunt related complications were noted in two of the four patients. Complications included bilateral lower extremity lumbar radiculopathy in one patient that resolved with a short course of gabapentin, spinal headache in one patient that resolved with bed rest and fluids, and development of a small intracranial subdural hygroma without mass effect in one patient that is asymptomatic and being followed without clinical consequence. Laparoscopic insertion of the abdominal catheter is safe and effective and does not appear to independently cause an increased risk of complications.

A model for idiopathic intracranial hypertension and associated pathological ICP wave-forms

Idiopathic intracranial hypertension (IIH) is a syndrome of unknown cause characterized by elevated intracranial pressure (ICP). While imaging often reveals a stenosis of the transverse sinuses, the role of this feature in IIH has been in dispute. Many patients with chronic daily headache have been found to actually be suffering from a milder form of IIH without papilledema (IIHWOP). These patients often demonstrate hypertensive B-waves and plateau-like waves upon continuous ICP monitoring. Recently, we presented modeling studies which suggest that the sinus stenosis and hypertension of IIH are physiological manifestations of a stable state of elevated pressures that exists when the transverse sinus is sufficiently collapsible. Many of the features of IIH were explained by this model but the prevalence of pathological ICP wave-forms observed in IIHWOP remained unresolved. The model presented here is a modified version of a previous model with a semi-collapsible sinus represented by a refined downstream Starling-like resistor based on experimental data. The qualitative behavior of this model is presented in terms of the collapsibility of the transverse sinus. For a sufficiently rigid sinus, there is a unique stable state of normal pressures. As the degree of collapsibility increases, there is a Hopf bifurcation, the normal state becomes unstable, low-frequency, high-amplitude ICP waves prevail, and small perturbations can lead to hypertensive ICP spikes. As the collapsibility increases further, so does the duration of the waves, until they are replaced by two stable states: one of normal pressures and one of elevated pressures. In this parameter domain, temporary perturbations can now cause permanent transitions between states. The model presented here retains the capability of our previous model to elucidate many features of IIH and additionally provides insight into the prevalence of the low-frequency, high-amplitude waves observed in IIHWOP.

[Bilateral papilledema: prospective study of fifty patients]

In this prospective study, we report fifty consecutive cases of bilateral papilledema without neurosurgical or obvious ophthalmologic etiology, referred to our institution between January 2005 and March 2007. Lumbar puncture with opening CSF pressure measurement distinguished two groups of patients: Group 1 (n=39) with and Group 2 (n=11) without intracranial hypertension. In Group 1, 9/39 patients presented secondary intracranial hypertension mainly due to cerebral venous thrombosis. In 30 patients, after complete investigations, a diagnosis of idiopathic intracranial hypertension was made: as commonly reported, patients were predominantly overweight (96.7% with body mass index>25kg/m2) young (mean age=27.6 years) and women (96.7%). Eleven patients with intracranial hypertension had no headaches. In Group 2, the most common diagnosis was bilateral non-arteritic anterior ischemic optic neuropathy, but rare causes have been identified.

Endovascular procedures for cerebrovenous disorders

Cerebral venous anomalies may have a variety of clinical consequences. MR or CT venogram can assist the imaging diagnosis; yet, cerebral angiogram may be required to confirm or establish the correct diagnosis. Venous anomalies predisposing venous hypertension may be categorized into three major entities such as congenital variations, outflow obstruction, and increased blood flow. The degree of clinical presentations of venous hypertension depends upon the chronicity or acuteness. Venous hypertension may lead to venous congestion with edema, hemorrhage and encephalopathy. Endovascular therapeutic procedures may be employed to relieve venous congestion either from reducing blood flow or relieving obstruction. Those endovascular treatment options include embolization, thrombolysis and angioplastic stentings.

Optic nerve sheath fenestration for vision preservation in idiopathic intracranial hypertension

Idiopathic intracranial hypertension, also known as pseudotumor cerebri, is a condition of increased intracranial pressure without the presence of mass lesions and with normal cerebrospinal fluid composition. Patients may experience papilledema and vision loss. Optic nerve sheath fenestration (ONSF) is one method of stabilizing visual function and decreasing optic nerve edema. The authors report on 10 patients who underwent bilateral ONSF and in whom visual function was stable or improved postoperatively. The results obtained in these cases suggest that ONSF plays a role in visual preservation in idiopathic intracranial hypertension patients in the acute setting.

Endoscopic free electron laser technique development for minimally invasive optic nerve sheath fenestration

PURPOSE

This study proposed to develop a technique for efficiently accessing the posterior orbital space using endoscopy and attempted application of free electron laser (FEL) energy, biopsy forceps, electrocautery, and CO(2) insufflation to posterior orbital tissues.

METHODS

Through an inferior transconjunctival incision, access to the posterior orbital space was attempted in 14 eyes of 7 non-survival pigs. FEL energy (6.1 microm, 30 Hz, delivered via 250 microm hollow-glass waveguide), biopsy forceps, and monopolar electrocautery application were endoscopically attempted in the posterior orbit. CO(2) gas insufflation effects were assessed by analyzing arterial blood gases at 30-minute intervals for 1.5 hours.

RESULTS

The posterior orbit was accessed in 13 of 14 eyes, the optic nerve was encountered, and FEL energy was applied in 8 of 14 eyes. Use of biopsy forceps and electrocautery were successful. Although ANOVA results for arterial blood gas changes were not statistically significant, visibility was adequate without CO(2) insufflation.

CONCLUSIONS

The posterior orbit was endoscopically accessed and the optic nerve was exposed and successfully treated with FEL energy. CO(2) insufflation did not alter blood gases, but did not further enhance visibility in this study.

Intracranial hypotension caused by leakage of cerebrospinal fluid from the thecal sac after lumboperitoneal shunt placement. Case report

The authors describe a newly recognized complication of lumboperitoneal (LP) shunt placement, namely, intracranial hypotension from leakage of cerebrospinal fluid (CSF) through a defect in the lumbar dura created by the shunt catheter. They report on a 47-year-old obese woman with idiopathic intracranial hypertension who underwent routine placement of an LP shunt. Following surgery, her headache became worse. Two radionuclide shunt studies showed no anterograde tracer flow, suggesting either obstruction or a leak. After shunt reservoir manometry indicated low pressure, spinal magnetic resonance (MR) imaging was performed. The MR images revealed a CSF leak from the lumbar thecal sac. A computed tomography (CT) myelogram, performed by injection into the shunt reservoir, confirmed the presence of a leak by showing extravasation of contrast agent into the epidural space. The patient was treated by application of a CT-guided blood patch at the leak site. Catheter-associated CSF leak is an unusual cause of intracranial hypotension that can occur following LP shunt placement. This case report outlines the clinical features of this condition, documents the neuroradiological findings, and demonstrates successful treatment with a blood patch.

Facial Palsy and Fallopian Canal Expansion Associated With Idiopathic Intracranial Hypertension

OBJECTIVE

Describe neurotologic findings associated with idiopathic intracranial hypertension (IIH).

STUDY DESIGN

Retrospective.

SETTING

Tertiary referral center.

PATIENTS

Case of IIH (>250 mm water) presenting with unilateral facial palsy and enlargement of the fallopian canal on computed tomography and magnetic resonance imaging.

INTERVENTION(S)

Oral acetazolamide, corticosteroids, and cerebrospinal fluid drainage.

MAIN OUTCOME MEASURE(S)

Intracranial pressure measurement, cranial nerve examination, audiometry, and symptom assessment.

RESULTS

Audiometry revealed asymmetric sensorineural hearing loss. Enlargement of the fallopian canal with cerebrospinal fluid was evident on imaging studies. Partial resolution of IIH symptoms was achieved.

CONCLUSION

IIH is an enigmatic disease entity. Increased intracranial pressure usually presents with headache and pulsatile tinnitus and is occasionally associated with cranial neuropathies. Abducens palsy is most common, producing diplopia. Cranial nerve involvement is often asymmetric, producing false localizing signs. Facial paralysis is an uncommon sequela of IIH. Treatment of IIH consists of reducing intracranial pressure. Corticosteroids are recommended for treatment of facial paralysis.

Pseudotumor cerebri from sinus venous thrombosis, associated with polycystic ovary syndrome and hereditary hypercoagulability

OBJECTIVE

The association of pseudotumor cerebri, visual impairment, hypothyroidism, polycystic ovary syndrome (PCOS), and a hypercoagulable state due to a factor V and a prothrombin mutation has not been reported previously.

CASE REPORT

A 20-year-old obese woman developed menstrual cycle irregularities since age 14 years, initially bitemporal and latter diffuse headache since age 14 years, and bilateral visual impairment, described as sparkling black points. Ophthalmologically there was a recurrent papilledema. Clinical neurologic investigations revealed sore neck muscles and hirsutism. Magnetic resonance imaging of the brain, orbita and cervical spine, and investigations of cerebrospinal fluid were non-informative. Visually evoked potentials revealed demyelination of the optic nerves. Gynecologic investigations revealed PCOS and endocrinologic investigations hypothyroidism and hyperandrogenism. Tests for thrombophilia disclosed a heterozygote state for the G1.697A factor V Leiden and the G20.210A prothrombin mutation. A possible relationship between pseudotumor cerebri and the ophthalmologic, gynecologic, endocrinologic and coagulation abnormalities is discussed.

CONCLUSIONS

For the first time we describe the association of pseudotumor cerebri, optic nerve demyelination, PCOS, other endocrinologic abnormalities, and thrombophilia due to a factor V and prothrombin mutation. A causal relationship between these abnormalities remains elusive.

Valve pressure upgrade may produce progressive deterioration of vision in children with slit ventricle syndrome

Recently, valve upgrade and/or endoscopic third ventriculostomy, which have the merit of no additional shunting, were introduced for the treatment of slit ventricle syndrome, because lumboperitoneal shunting entails various complications including development of Chiari malformation, shunt malfunction, and infection. However, the safety of valve upgrading is not confirmed, especially in a child with slit ventricle syndrome developed as a result of pseudotumor cerebri. A 5-year-old boy with pseudotumor cerebri presented with headache, intermittent vomiting, and sudden deterioration of visual acuity. His cerebrospinal pressure during lumbar puncture was 69 cm H(2)O and his magnetic resonance imaging revealed only small ventricles. He underwent a ventriculoperitoneal shunt resulting in dramatic improvement. Four months later, he returned with recurrent spontaneous valve malfunction with recurrent severe headache and visual deterioration. After shunt revision with a programmable valve, his intermittent valve malfunction was improved by upgrading the valve opening pressure. However, his visual acuity became progressively aggravated. He underwent a lumboperitoneal shunt with low-pressure valve, which resulted in the disappearance of intermittent headaches and a deterioration of visual acuity. We suggest that valve pressure upgrade in children with slit ventricle syndrome after ventriculoperitoneal shunt for pseudotumor cerebri may produce acute deterioration of vision that had already been compromised, even within the normal intracranial pressure range and with improvement of associated symptoms.

Pseudotumor cerebri after allogeneic bone marrow transplant associated with cyclosporine a use for graft-versus-host disease prophylaxis

Pseudotumor cerebri (PTC) is a syndrome of increased intracranial pressure for which several risk factors have been described. We report 2 patients who developed PTC after cyclosporine A (CsA) therapy for graft-versus-host disease (GvHD) prevention after bone marrow transplant. Both patients were obese which may have also contributed to the PTC. Cessation of CsA and combinations of mycophenolate mofetil or tacrolimus and systemic steroids and/or acetazoleamide were effective in managing the symptoms, improving the ocular complications and keeping GvHD asymptomatic. These cases suggest that induction of PTC by CsA used for GvHD prophylaxis in patients undergoing bone marrow transplant is not rare. Physicians who are following patients on CsA need to be alert to the possibility of PTC. Prompt diagnosis followed by thorough evaluation and treatment are crucial for preventing visual loss and improving associated symptoms.

Changes in weight, papilledema, headache, visual field, and life status in response to diet and metformin in women with idiopathic intracranial hypertension with and without concurrent polycystic ovary syndrome or hyperinsulinemia

The authors hypothesized that a metformin (MET)-diet would improve symptoms of idiopathic intracranial hypertension (IIH) in women who also had polycystic ovary syndrome (PCOS) or hyperinsulinemia without PCOS. Changes in weight, papilledema, headache, visual fields, and overall life status were prospectively assessed in response to 6 to 14 months on 2.25 g/day MET-diet or diet alone in 36 women with IIH, 23 with PCOS, selected by baseline body mass index (BMI) > or = 25, and no previous surgery for IIH. Overall life status was graded using a self-reported 1-5 scale (1 = well, normal activities; 2 = unwell, usual activities; 3 = poor, usual activities; 4 = poor, no usual activities; 5 = totally disabled). Conventional treatment for IIH was maintained unchanged during MET-diet intervention. The diet was hypocaloric (1500 calories/day), high protein (26% of calories), and low carbohydrate (44%). Of the 23 women with PCOS, 20 received MET-diet and 3 diet only (could not tolerate MET). Of the 13 women without PCOS, 7 were hyperinsulinemic and received MET-diet and 6 received diet alone. The 3 treatment groups (diet only [n = 9], PCOS-MET-diet [n = 20], and hyperinsulinemia-MET-diet [n = 7]) did not differ by median entry BMI (33.3, 37.6, and 35.7 kg/m(2)) or by duration of treatment (10.2, 11.4, and 10.9 months). Median percent weight loss was greatest in the PCOS-MET group (7.7%, P = 0.0015), was 3.3% in the diet only group, and 2.4% (P = 0.04) in the hyperinsulinemia-MET group. Papilledema significantly improved in the diet-alone group from 100% at baseline to 13% (P = 0.03), and in the PCOS-MET group from 95% to 30% (P = 0.002). If headache persisted on therapy, it was less intense-less frequent (P = 0.03) in the diet-only group and in the PCOS-MET group (P = 0.04). As many women with IIH have PCOS, and because weight loss is central to IIH treatment, diet-MET is a novel approach to treat IIH in women with concurrent PCOS or hyperinsulinemia without PCOS.

Perfusion and diffusion magnetic resonance imaging in idiopathic intracranial hypertension

OBJECTIVES

Idiopathic intracranial hypertension (IIH) is characterized by abnormal elevation of intracranial pressure without any underlying etiologic factor. Papilledema is the major clinical finding whereas neuroradiological imaging findings are almost always normal. The aim of this preliminary study was to determine if diffusion and perfusion magnetic resonance imaging in patients with IIH might be beneficial in the management of the disease.

MATERIALS AND METHODS

Prospectively, we evaluated standard magnetic resonance, magnetic resonance angiographies and venographies, diffusion and perfusion magnetic resonance findings of 16 patients with IIH and of 16 age-, sex-, and weight-matched normal individuals as a control group. Patients with IIH underwent a detailed neuroophthalmologic examination and lumbar puncture for evaluation of cerebrospinal fluid pressure. Magnetic resonance imaging was performed with 1.5 T equipment.

RESULTS

On physical examination, all patients had characteristic papilledema, varying degrees of headache, blurred vision and tinnitus. Cerebrospinal fluid pressure was higher than 250 mm H2O in all patients. A statistically significant decrease in cerebral blood flow in six patients, whereas insignificant increase in two were detected. Cerebral blood volume values were almost similar to normal control group's values. Significant mean transit time prolongation was found in six patients as well.

CONCLUSIONS

Idiopathic intracranial hypertension is a clinical syndrome which requires prompt diagnosis and a thorough evaluation. Treatment is crucial for preventing visual loss and improving associated symptoms. It is also important to detect cerebral perfusion changes, as cerebrovascular complications may be associated. Although our patient group is small for statistical evaluation, it is a preliminary study using perfusion and diffusion magnetic resonance which may contribute to IIH management.

Shunt failure in idiopathic intracranial hypertension presenting with spontaneous cerebrospinal fluid leak

A case of spontaneous cerebrospinal (CSF) fluid leak after ventriculoperitoneal shunt (VPS) failure in a patient with idiopathic intracranial hypertension (IIH) is reported. This is the first report of spontaneous CSF leak in an IIH patient without a history of trauma, sinus surgery, or intracranial surgery. The diagnosis was confirmed using thin-sliced post-contrast computed tomography, which revealed a micro-dehiscence of the cribiform plate at the superior aspect of the ethmoid sinus. The patient underwent VPS revision without complication, resulting in complete amelioration of symptoms and cessation of CSF rhinorrhoea at 1 year follow up.

Depressed skull fracture overlying the superior sagittal sinus causing benign intracranial hypertension. Description of two cases and review of the literature

The purpose of this report is to describe successful surgical treatment of benign intracranial hypertension (BIH) in two patients presenting with depressed skull fractures over the superior sagittal sinus (SSS). The first case involved a 22-year-old patient who presented with depressed skull fracture overlying the posterior third of the SSS. Symptoms of BIH developed within 48 h. The second case involved a 33-year-old patient who presented with depressed skull fracture overlying the junction between the middle and posterior thirds of the SSS. Symptoms of BIH developed 1 month after. Although this patient presented with bilateral papilloedema, the less straightforward nature of his BIH symptoms prompted us to undertake further neuroradiological assessment by angiography with retrograde venous catheterization. A high-pressure gradient was found between venous flow upstream and downstream from the compressed zone. Both patients underwent surgical decompression in the lateral decubital position. Continuous monitoring of intracranial pressure was begun upon induction of general anaesthesia. High preoperative pressure declined immediately after elevation of the depressed zone. Bleeding was not a problem at any time during the procedure. Follow-up MRI and angio-MRI demonstrated total restoration of SSS patency. Benign intracranial hypertension is an uncommon complication of depressed skull fracture. Retrograde venous catheterization with pressure measurement can be a useful diagnostic adjunct. Surgical treatment is indicated in symptomatic patients. Based on the two cases reported, we now propose MRI venography in all patients presenting with symptoms of BIH and arteriography with retrograde venous catheterization when venous sinus stenosis exists.