Idiopathic syndrome caused by increased intracranial
pressure with papilledema of unknown origin, most often presenting with symptoms of
cerebral tumor (pseudotumor cerebri) in young obese women in
their childbearing years.
Benign Intracranial Hypertension; Pseudotumor Cerebri.
Clinical syndrome characterized by increased intracranial
pressure of unknown origin with good prognosis if medical treatment
(acetazolamide) is regularly taken. Severe cases (visual impairment) require
The incidence in the United States has been reported to
range from 0.9-1.0:100,000 in the general population; however, this rate is
estimated to be 1.6-3.5:100,000 in women and 7.9-19:100,000 in overweight
women. Internationally, the incidence varies considerably among countries.
However, the relationship between personal habitus such as obesity has been
confirmed. In Libya, it has been demonstrated that the incidence was
estimated at 2.2:100,000 in the general population, 4.3:100,000 in women,
and 21.4:100,000 in obese women.
Idiopathic intracranial hypertension is a clinical
syndrome characterized by an elevated intracranial pressure with normal
cerebrospinal fluid (CSF) composition and no evidence of any expanding
intracranial mass lesion or significant hydrocephalus. In all cases, increased
vitamin A concentration is measured in the CSF of affected women. Females are
more affected than males. Most often, no specific cause is found; however,
multiple causes have been identified: endocrine and metabolic disorders
(hypoparathyroidism, pseudohypoparathyroidism, corticosteroid therapy
withdrawal, growth hormone treatment, hypervitaminosis A, Addison disease,
obesity, menarche, oral contraceptives, pregnancy, galactosemia), hematologic
disorders (iron deficiency and hemolytic anemia, polycythemia, Wiskott-Aldrich
syndrome), infections (roseola infantum, chronic otitis media and mastoiditis,
Guillain-Barré syndrome), drugs (tetracyclines, nalidixic acid), and
obstruction of intracranial drainage by venous thrombosis (head injury, lateral
or posterior sagittal sinus thrombosis, obstruction of superior vena cava).
Clinical course; CT scan or MRI excluding any structural
cause for increased intracranial pressure and showing normal ventricles;
lumbar puncture revealing elevated CSF opening pressure and normal CSF
composition (chemistry, cytology, bacteriology). Lumbar puncture is
therapeutic, allowing CSF to escape, thereby reducing the intracranial
pressure. Digital subtraction angiography may be performed if there is
suspicion of venous thrombosis.
Some patients are asymptomatic. Infants may
present with irritability, bulging fontanelle, and a resonant sound on skull
percussion (MacEwen sign). Headache, pulsatile intracranial noises,
occasional vomiting, transient visual obscuration, diplopia secondary to
abducens nerve paralysis, and intermittent gait ataxia are possible findings
in children and adults. Examination reveals papilledema without significant
focal neurologic signs. Visual loss from optic neuropathy may occur as a
long-term sequela. Treatment is aimed at controlling intracranial pressure
in order to preserve the vision.
Obtain a full history of any
associated disorder (endocrine, hematologic, drug-related, infectious, or
obstructive secondary to venous thrombosis). Inquire about the use of
therapy to control the presence of benign intracranial hypertension, such as
corticosteroids, diuretics (acetazolamide with/without furosemide), repeated
therapeutic lumbar punctures, and surgical lumboperitoneal shunting. Obtain
electrolytes and glucose levels for patients on steroid or diuretic therapy.
In patients receiving steroids, consider