Approach Considerations
The care of patients with pseudotumor cerebri requires a multidisciplinary approach. Neurosurgical interventions are sometimes needed for diagnostic and treatment purposes. Prompt and accurate communication among specialists is necessary to ensure timely treatment and optimal outcomes. [29]
Medical therapy appeared to be successful in treating pediatric pseudotumor cerebri in most patients. However, despite adequate treatment, children can rarely experience loss of visual field and acuity; thus, prompt diagnosis and management are important. [30] Sometimes, the symptoms of idiopathic intracranial hypertension (IIH) resolve with the initial diagnostic lumbar puncture. If this occurs, no further medical treatment is required. When medical treatment is required, most children respond to medications such as steroids, acetazolamide, furosemide, or topiramate.
Surgical treatment such as optic nerve sheath fenestration, sinus stenting, and shunting procedures are indicated for children with severe headaches, visual loss, or both, despite maximal tolerated medical treatment. [6, 31]
The most serious potential complication is permanent visual loss and blindness. Low-salt diet and weight loss may be beneficial. The authors’ experience suggests that weight loss is difficult to achieve in the overweight adolescent.
Consultations with an optometrist, a neuro-ophthalmologist, and/or a pediatric neurologist may be indicated. [29] Neuro-ophthalmology follow-up with frequent assessment of visual fields is indicated.
Although IIH 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. [7]
In a study by Elder et al, data show that transverse sinus stenting, in conjunction with temporary CSF diversion, represents an appropriate treatment option in the acute setting. [32]
Pharmacologic Therapy
Acetazolamide is administered at an initial dosage of 25 mg/kg/day, which is titrated upward until a clinical response is attained (maximum, 100 mg/kg/day). Electrolyte concentrations must be monitored to evaluate for the development of hypokalemia and acidosis. If the patient remains on treatment for more than 6 months, renal ultrasonography should be ordered to look for the presence of renal calculi. If acetazolamide is ineffective, prednisone can be given at a dosage of 2 mg/kg/day for 2 weeks, followed by a 2-week taper.
Topiramate is now being widely used in the treatment of migraine and IIH in adults. Topiramate functions as a carbonic anhydrase (CA) inhibitor and appears to be efficacious in the treatment of both conditions. This medication may prove to be useful in selected children with IIH.
Repeat lumbar puncture may help in some patients, but its invasiveness and the difficulty of performing it in children make it a less than ideal medical therapy. The reduction in pressures is often only transient.
A low-salt diet and weight reduction have been shown to be helpful in adult patients. If the child is obese, weight reduction may be beneficial.
Optic Nerve Sheath Fenestration and CSF Diversion
The main indications for surgical intervention to treat IIH are deterioration in vision and incapacitating headaches despite aggressive medical management. There are 2 main surgical approaches to the treatment of pediatric IIH: optic nerve sheath fenestration and CSF diversion (typically, lumboperitoneal shunting). [5] The authors prefer optic nerve fenestration to lumboperitoneal shunting.
Optic nerve sheath fenestration (ONSF) has been shown to improve visual outcome. It yields better results in patients with acutely decompensating vision and papilledema. Lumboperitoneal shunting may relieve headache and reduce ICP in patients with IIH. The long-term visual outcome of patients treated with this procedure is unknown. Complications include infection and shunt obstruction. Low-pressure headaches have also been reported to develop as a result of lumboperitoneal shunting.
There are pros and cons for doing either ONSF or CSF diversion. However, the decision for ONSF versus CSF shunting is somewhat institution- and surgeon-dependent. ONSF is preferred for patients with visual symptoms whereas shunting is reserved for patients with headache. [33]
-
For IIH to be diagnosed, brain scans (such as MRI) must be performed to ensure there is no underlying cause for the increased pressure around the brain
-
Left optic disc with moderate chronic papilledema in patient with idiopathic intracranial hypertension (pseudotumor cerebri). Paton lines (arc-shaped retinal wrinkles concentric with disc margin) are seen along temporal side of inferior pole of disc.
-
Right optic disc with postpapilledema optic atrophy in patient with idiopathic intracranial hypertension (pseudotumor cerebri). Diffuse pallor of disc and absence of small arterial vessels on surface are noted, with very little disc elevation. Disc margin at upper and lower poles and nasally is obscured by some residual edema in nerve fiber layer and gliosis that often persists even after all edema has resolved.
-
Most common early visual field defect in papilledema as optic nerve develops optic atrophy is inferior nasal defect, as shown in left eye field chart (left side of figure). Shaded area indicates defective portion of field. Note sharp line of demarcation between defective lower nasal quadrant and normal upper nasal quadrant along horizontal midline. This is characteristic of early papilledema optic atrophy and is referred to as nasal step or inferonasal step.