Emergent Care / Stabilization: 
Any patient presenting with vision loss should be referred to the emergency department for further evaluation and immediate reduction of intracranial pressure, usually through serial lumbar puncture and cerebrospinal fluid (CSF) drainage and initiation of acetazolamide pending more definitive surgical management. 

Diagnosis Overview: 
Idiopathic intracranial hypertension (IIH), historically referred to as benign intracranial hypertension or pseudotumor cerebri, is a clinical syndrome with elevated CSF pressure (greater than 25 cm H₂O) as measured with the patient in a lateral decubitus position, with normal composition (ie, negative CSF studies),  without any evidence of hydrocephalus, mass, or structural or vascular lesions, and without any known cause. It is usually associated with headache and papilledema.

The most common presenting symptom of IIH is headache, occurring in 68%-98% of patients. The headache may be exacerbated by coughing or straining and is often severe. Other complaints may include blurred vision, loss of vision, transient obscurations of vision (may be postural), diplopia (due to sixth nerve palsy), tinnitus or intracranial noise, pain (of neck, arm, shoulder, or behind the eye), and nausea. Many patients have some degree of vision loss (up to 32% in one review).

IIH is increasing in prevalence because of its association with obesity. It has a strong association with weight gain, particularly in women of reproductive age. It occurs in 1 in 500 females with a body mass index (BMI) higher than 30, most commonly in the setting of recent weight gain. Female-to-male ratios of the disorder range from 4:1 to 15:1. Reported frequencies of obesity in individuals with IIH are 71%-94%, although obesity is less of a factor in men and children younger than 10 years.

Several drugs have been associated with intracranial hypertension, most commonly tetracycline antibiotics, oral retinoids / retinols, and steroids (specifically anabolic steroids or withdrawal from long-term corticosteroid use). Estrogen hormones, nalidixic acid, nitrofurantoin, indomethacin, rofecoxib, lithium, cyclosporine, and cimetidine have also been associated with the disorder.

Medical problems such as systemic hypertension, obstructive sleep apnea, polycystic ovary syndrome, diabetes mellitus, thyroid disease, ulcerative colitis, systemic lupus erythematosus, sickle cell disease, anemia, cystinosis, and renal transplant have been associated with IIH, although some of these patients may have had undiagnosed cerebral venous sinus thrombosis. Despite awareness of various risk factors in association with IIH, the pathogenesis remains unclear.

Pediatric Patient Considerations:
IIH is found in young children as well, without the same predominance of obesity and female sex as in adults and teens. Pediatric patients are more likely to present with systemic signs and symptoms such as headache, lethargy, anorexia, and drowsiness. With prompt diagnosis and treatment, these patients generally have a good prognosis.