Idiopathic "benign" intracranial hypertension: case series and review.

Idiopathic "benign" intracranial hypertension is an uncommon but important cause of headache that can lead to visual loss. This study was undertaken to review our experience in the diagnosis and management of idiopathic intracranial hypertension, giving special attention to treatments used. A retrospective chart review was conducted on 32 patients diagnosed with idiopathic intracranial hypertension between 1984 and 1995. Subjects included 23 females and ranged in age from 2 to 17.5 years. Headache was the most common symptom, followed by nausea and vomiting, double vision, and visual loss. Papilledema was the most common sign. Others were VIth cranial nerve palsy and compromised visual acuity at or within 3 months of presentation. Management included administration of acetazolamide or corticosteroids, lumboperitoneal shunt, optic nerve fenestration, and repeat lumbar puncture. Treatment combinations were used in 40% of cases. During follow-up, headache, papilledema, and decreased visual acuity persisted for longer than 10 months in a significant number of patients. We conclude that idiopathic intracranial hypertension causes significant short- and long-term morbidity with no proven effective treatment available. A prospective study is needed to establish the indications for treatment and the efficacy of the treatments used.     

Idiopathische intrakranielle Hypertension

This review describes the clinical findings as well as thes diagnostic and therapeutic options for idiopathic intracranial hypertension (pseudotumor cerebri). Furthermore, the pathophysiological concepts are discussed. Idiopathic intracranial hypertension is characterized by signs and symptoms of raised intracranial pressure with no established pathogenesis. Common symptoms include headaches, visual loss and pulsatile tinnitus. Treatment has two major goals: the alleviation of headaches and the preservation of vision. Weight loss and acetazolamide are the cornerstones in the treatment of the disorder. Drainage of cerebrospinal fluid, optic nerve sheath fenestration and stent angioplasty of a sinus stenosis can be employed in severe cases.     

Benign intracranial hypertension

Benign intracranial hypertension (BIH) is characterized by an elevation of the intracranial pressure not associated with an intracranial process or hydrocephaly, and with normal cerebrospinal fluid (CSF) contents. The elevation of the intracranial pressure is isolated; therefore, diseases such as cerebral venous thrombosis or dural fistulas should not be considered as etiologies of BIH. The exact definition of BIH remains debated, and other terms such as "pseudotumor cerebri" or "idiopathic intracranial hypertension" are often used in the literature. Although we agree that BIH is usually not a so benign disease, we suggest that BIH is still the most appropriate term to describe this entity which should be classified as "secondary BIH" or "idiopathic BIH" depending on whether there are precipitating factors for the development of BIH or not. We also propose new diagnostic criteria emphasizing the need for investigations for the diagnostic of secondary and idiopathic BIH. The management of patients with BIH depends mainly on the presence and severity of ocular symptoms and signs on which the prognostic of the disease is based. Repeated lumbar punctures associated with acetazolamide and weight loss are usually efficient enough. However a surgical treatment (optic nerve sheath fenestration or lumboperitoneal shunt) is required when appropriate medical management does not prevent progressive alteration of vision (visual loss or visual field defect), or when the patients complains of severe, refractory headaches. Careful follow-up with repeated formal visual field testing may help preventing a devastating visual loss in these patients.     

Subretinal hemorrhage from a peripapillary choroidal neovascular membrane in papilledema caused by idiopathic intracranial hypertension.

A 42-year-old man with idiopathic intracranial hypertension and chronic papilledema had severe visual loss in his left eye caused by subretinal bleeding from a peripapillary choroidal neovascular membrane (CNVM). After optic nerve sheath fenestration in his left eye, the papilledema improved, allowing improved visualization of the CNVM. Visual function did not improve after the surgery. CNVM can complicate chronic papilledema and account for sudden worsening of vision. The appropriate management of this type of CNVM is unresolved.     

Cranial disjunction and visual failure in a slit ventricle syndrome with patent shunt

A 6.5-year-old child who received a shunt at 3 weeks of age for triventricular hydrocephalus related to his congenital toxoplasmosis developed symtoms of intracranial hypertension and papilloedema. Computed tomographic scan demonstrated slit ventricles. The shunt device was shown to be patent on isotope transit study. Spontaneously the cranial sutures widened and headaches disappeared, but loss of vision occurred and did not reverse despite optic nerve sheath fenestration. We suspect that a rapid drop in intracranial pressure played a role in the pathogenesis of our patient's blindness. This possible complication should be taken into account when calvarial expansion is planned in a patient with an intracranial hypertension syndrome with papilloedema in the presence of slit ventricles and a patent shunt.     

Idiopathic intracranial hypertension without papilledema

We describe 10 patients with idiopathic intracranial hypertension who did not have papilledema. Idiopathic intracranial hypertension without papilledema, although rarely reported, may well be a clinically important headache syndrome. Historical and demographic features of patients with idiopathic intracranial hypertension without papilledema are similar to those of patients with papilledema. Obese women with chronic daily headache and symptoms of increased intracranial pressure, pulsatile tinnitus, history of head trauma or meningitis, an empty sella on imaging studies, or a headache that is unrelieved by standard therapy should have a diagnostic lumbar puncture. Findings from laboratory and neurologic investigations are normal in most patients with idiopathic intracranial hypertension without papilledema. Initial management should include removal of possible inciting agents, weight loss if applicable, and standard headache therapy. Lumbar puncture and diuretic therapy should precede a trial of corticosteroids. Surgery (lumboperitoneal or ventriculoperitoneal shunt or perhaps optic nerve sheath fenestration) may be indicated for prolonged incapacitating headache that is not responsive to medical management or lumbar puncture.     

The rational management of idiopathic intracranial hypertension

Idiopathic intracranial hypertension is a diagnosis most frequently made in young, overweight women. The chief hazard to the patient is permanent visual loss due to chronic papilledema. After the diagnosis has been clearly established using lumbar puncture and imaging techniques, the neurologist is involved in helping to lower the intracranial pressure, control the headaches, and encourage weight loss. Careful vision monitoring is essential and should be done in collaboration with an ophthalmologist. Visual fields, fundus photographs, intraocular pressure measurement, and visual acuity should be performed at each follow-up visit. The use of visual evoked response and repeated measurement of intracranial pressure by lumbar puncture do not provide data that help to guide therapeutic decisions. Indications for surgery are loss of visual field or decline in visual acuity in the fact of medical therapy, persistent headache, or the inability to perform visual-function studies. Optic nerve sheath fenestration and lumbar peritoneal shunt both appear to be effective surgical means to reduce the pressure on the optic disc. A neurologist and an ophthalmologist working together provide the evidence on which to base rational decisions in the care of the patient with idiopathic intracranial hypertension.     

Papilledema: Are We Any Nearer to a Consensus on Pathogenesis and Treatment?

Papilledema is a term generally reserved (at least in the English language use of the term) by neuro-ophthalmologists for optic disc edema due to increased intracranial pressure. The etiology for the intracranial hypertension may be known (e.g., brain tumor, meningitis, cerebral venous sinus thrombosis) or may be idiopathic (idiopathic intracranial hypertension [IIH]). IIH is a disorder that predominantly affects overweight women of childbearing age and these epidemiologic factors should offer clues to pathogenesis. The main morbidity of papilledema is visual loss and the major mechanism for permanent optic nerve damage is axoplasmic flow stasis and resultant intraneuronal ischemia. The current initial management of papilledema in IIH includes weight loss and medical therapy (e.g., acetazolamide or furosemide). Patients who fail, are intolerant to, or noncompliant with maximum tolerated medical therapy might require optic nerve sheath fenestration or cerebrospinal fluid diversion (i.e., shunting) procedures.     

Optic nerve sheath decompression for the treatment of visual failure in chronic raised intracranial pressure.

The records of all patients undergoing optic nerve sheath decompression for visual failure in chronic raised intracranial pressure performed over a 15 year period have been reviewed. The aim was to study the visual outcome and relation to any shunting procedures. Fourteen patients (20 eyes) were identified in whom follow up information of at least one year was available. Eleven patients had benign intracranial hypertension (idiopathic intracranial hypertension) and three had dural venous sinus occlusive disease. Eight patients had unilateral surgery and six had bilateral surgery. Visual acuity and fields either improved or stabilised in 17 out of 20 eyes and three deteriorated. Of the eight patients undergoing unilateral surgery, the other eye remained stable in seven and deteriorated in one. Four patients required optic nerve sheath decompression despite previous shunting or subtemporal decompression. Five patients required shunts or subtemporal decompression after optic nerve sheath decompression because of persistent headache in three cases and for uncontrolled visual failure in two cases. No patients lost vision as a direct consequence of surgery. It is concluded that optic nerve sheath decompression is a safe and important therapeutic option in the management of chronic raised intracranial pressure complicated by visual loss. Vision can be saved after shunt failure, and in other cases may be maintained without the need for a shunt. Shunts may still be required, however, after optic nerve sheath decompression, especially for persistent headache.     

Idiopathic intracranial hypertension: mechanisms of visual loss and disease management

Idiopathic intracranial hypertension (IIH) is a disorder of increased intracranial pressure of unknown cause. It is a disorder, predominantly of overweight women in the childbearing years. The major morbidity of the disease is visual loss. Damage to the visual system occurs at the optic nerve head. This damage is most likely due to axoplasm flow stasis and resultant intraneuronal ischemia. Management of IIH begins with educating the patient about the disease and its potential outcomes. I recommend modest dieting and following a low-salt regimen with caution against overuse of fluids. Acetazolamide and Lasix appear to be efficacious. Patients failing medical therapy have optic nerve sheath fenestration performed if visual loss is the main morbidity. Shunting procedures are considered if headache is the main symptom. Most patients respond well to therapy, but idiopathic intracranial hypertension may recur throughout life.     

Resolution of headache and papilledema in idiopathic intracranial hypertension associated with inhibition of Na+-K+-2Cl- cotransport

Medical treatment of idiopathic intracranial hypertension is often ineffective. Cerebrospinal fluid diversion or optic nerve sheath fenestration is employed when medical therapy fails. Here, we describe a case of a 13-year-old girl with idiopathic intracranial hypertension refractory to long-term trials of acetazolamide and furosemide at maximally tolerated doses. After declining surgical intervention despite progression of her visual symptoms, a trial of bumetanide (0.25 mg daily) monotherapy was successful in resolution of the patient's symptoms. These results suggest bumetanide could be effective in the treatment of idiopathic intracranial hypertension, perhaps by restoring the balance between cerebrospinal fluid formation and absorption and/or by altering the volume or ionic composition of the brain's extracellular fluid compartment.     

Treatment of visual loss in pseudotumor cerebri associated with uremia

Ten patients with pseudotumor cerebri associated with renal insufficiency had papilledema and elevated intracranial pressure, but neurologic examinations and CT were normal. The 40% frequency of severe visual loss, 20/100 or worse, was higher than expected for pseudotumor cerebri. While furosemide was effective in 3 patients with renal transplants, administration of corticosteroids to 2 other patients did not halt progressive loss of vision. The visual function of 2 patients deteriorated even after lumboperitoneal shunting. Five patients underwent fenestration of the optic nerve sheath. This procedure improved the visual acuity of 3 patients and stabilized vision in the others. While the pathogenesis of pseudotumor cerebri in renal insufficiency is unknown, optic nerve sheath fenestration is the surgical treatment of choice for visual loss unresponsive to medical therapy.     

Benign intracranial hypertension and facial diplegia

Benign intracranial hypertension (BIH) may occasionally be associated with false localizing cranial nerve palsies. Abducens nerve palsies reportedly occur in 10% to 60% of patients with BIH, whereas other cranial nerve palsies occur much less frequently. We treated a woman with benign intracranial hypertension and facial diplegia who showed complete resolution of her cranial nerve palsies after control of her elevated intracranial pressure with a lumboperitoneal shunt. The pathophysiologic course of cranial nerve palsies in patients with BIH is uncertain but in most cases probably represents a nonspecific pressure-related phenomenon, as was clearly demonstrated in this patient. The clinical association of BIH and facial diplegia has not, to our knowledge, been reported previously.     

Complete ophthalmoplegia: A rare presentation of idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH) is a disorder defined by clinical criteria that include signs and symptoms isolated to those produced by increased intracranial pressure (ICP; e. g., headache, papilledema, and vision loss), elevated ICP with normal cerebrospinal fluid (CSF) composition, and no other cause of intracranial hypertension evident on neuroimaging or other evaluations. The most common signs in IIH are papilledema, visual field loss, and unilateral or bilateral sixth cranial nerve palsy. Here we report a case of IIH presenting as headache with vision loss, papilledema, complete ophthalmoplegia with proptosis in one eye, and sixth cranial nerve palsy in the other eye. Patient was managed with acetazolamide, topiramate, and diuretics. Symptoms remained static and she was planned for urgent CSF diversion procedure.     

Idiopathic intracranial hypertension (Pseudotumor cerebri)

Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a disorder of elevated intracranial pressure of unknown cause. Patients present with daily headache, pulse-synchronous tinnitus, transient visual obscurations, papilledema with its associated visual loss, and diplopia from sixth nerve paresis. Many disease associations have been alleged, but few besides obesity, hypervitaminosis A and related compounds, steroid withdrawal, and female gender have been proven. Although absorption of cerebrospinal fluid (CSF) occurs through arachnoid granulations and extracranial lymphatics, outflow resistance is increased in IIH; therefore, intracranial pressure must increase for CSF to be absorbed. The mainstays of medical treatment are a reduced-sodium weight-reduction program and acetazolamide. If patients fail medical therapy, surgical procedures, most commonly optic nerve sheath fenestration and CSF shunting, are employed. The main morbidity of IIH is visual loss. This is present in most patients and can usually be reversed if recognized early in the course of the disease and treated. Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a disorder of elevated intracranial pressure of unknown cause. Patients present with daily headache, pulse-synchronous tinnitus, transient visual obscurations, papilledema with its associated visual loss, and diplopia from sixth nerve paresis. Many disease associations have been alleged, but few besides obesity, hypervitaminosis A and related compounds, steroid withdrawal, and female gender have been proven. Although absorption of cerebrospinal fluid (CSF) occurs through arachnoid granulations and extracranial lymphatics, outflow resistance is increased in IIH; therefore, intracranial pressure must increase for CSF to be absorbed. The mainstays of medical treatment are a reduced-sodium weight-reduction program and acetazolamide. If patients fail medical therapy, surgical procedures, most commonly optic nerve sheath fenestration and CSF shunting, are employed. The main morbidity of IIH is visual loss. This is present in most patients and can usually be reversed if recognized early in the course of the disease and treated.     

Familial benign intracranial hypertension.

Three sisters with benign intracranial hypertension are reported. This is the first documentation of benign intracranial hypertension in three family members. Obesity is a striking feature in these patients as well as five of the six previously reported patients with familial benign intracranial hypertension. Pregnancy and chronic dysfunctional uterine bleeding, well known predisposing factors in this syndrome when it occurs sporadically, were present in two of the sisters. A familial metabolic defect may be responsible for the intracranial hypertension in these patients.     

Pseudotumour cerebri syndrome due to cryptococcal meningitis.

Three cases are reported of the pseudotumour cerebri syndrome-that is, intracranial hypertension without mass lesion or enlarged ventricles, due to cryptococcal meningitis. In these patients the papilloedema was successfully treated with optic nerve sheath decompression, and the intracranial hypertension with lumboperitoneal CSF shunting. These cases support the concept that pseudotumour cerebri is a syndrome of intracranial hypertension that can be due to any disorder producing obstruction of the CSF pathways at the level of the arachnoid villi. This concept is important because it directs therapy to normalise the intracranial pressure and preserve vision.     

A case of benign intracranial hypertension with fluctuated symptoms and CSF pressure synchronized with menstrual cycle]

A 39-year-old woman presented with a 2-month history of repeated severe headache, nausea and diplopia. On admission she was obese with bilateral papilledma and abducens weakness. Mass lesion and sinus thrombosis were ruled out by brain CT and angiography. CSF pressure was normal initially. CSF pressure fluctuated with menstrual cycle, sometimes showing over 600 mmH2O with worsening of the symptoms. She was diagnosed as benign intracranial hypertension (BIH). Diuretics did not improve the symptoms, and visual disturbances ensued and deteriorated. A spinal subarachnoid space-peritoneal shunt was inserted to control CSF pressure, showing rapid improvement of headache and diplopia but visual disturbances remained almost unchanged. Optic nerve sheath fenestration was performed without improvement of visual deterioration. We postulated multiple factors such as obesity, menstrual abnormality, iron deficiency anemia and analgesic drugs played important roles to produce BIH in this case. Careful quantitative perimetry should be done to decide a suitable time for surgical treatment in BIH.     

Cerebrospinal fluid neurohypophysial peptides in benign intracranial hypertension.

The cerebrospinal fluid (CSF) concentrations of arginine vasopressin (AVP) and oxytocin (OT) were investigated both in patients with benign intracranial hypertension and in age and sex matched controls. Twenty eight lumbar punctures were performed on 15 patients with benign intracranial hypertension as part of their routine investigation and therapy. All patients had raised intracranial pressure (27.4, SE 1.7 cm.CSF). CSF AVP levels were significantly elevated in benign intracranial hypertension (2.1, SE 0.3 pmol/l) compared with controls (0.7, SE 0.1 pmol/l, p less than 0.001) but CSF OT concentrations were similar in both groups. CSF osmolality and plasma AVP and osmolality were identical in patients and controls. There was no correlation between CSF AVP concentration and intracranial pressure. The selective elevation of AVP in CSF may be of importance in the pathogenesis of raised intracranial pressure in benign intracranial hypertension.     

Idiopathic intracranial hypertension

Dhungana S, Sharrack B, Woodroofe N. Idiopathic intracranial hypertension.
Acta Neurol Scand: 2010: 121: 71–82.
© 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Idiopathic intracranial hypertension (IIH) is a condition which affects predominantly overweight women and is characterized by raised intracranial pressure without any identifiable pathology in the brain and with normal cerebrospinal fluid (CSF) composition. The cause of IIH is unclear and as such it remains a diagnosis of exclusion. Although the pathophysiology of IIH remains elusive, some observations have recently been added to our understanding of this, including the presence of transverse sinus stenosis on many patients and the possible role of leptin and inflammation in the disease pathogenesis. Headache is the most common symptom and papilloedema is the major clinical finding. Choices of medical treatment are limited to the use of diuretics particularly acetazolamide and encouragement of weight loss. Surgical therapies such as CSF diversion procedures and fenestration of the optic nerve may be necessary in some cases with persistent symptoms or progressive visual deterioration. While not life‐threatening, IIH has a significant morbidity with up to 25% of patients developing visual impairment from optic atrophy. Visual surveillance is therefore vital. Long‐term follow‐up is recommended as the disease may worsen after an initial period of stability.