117A.Q. Rana, J.A. Morren, Neurological Emergencies in Clinical Practice, DOI 10.1007/978-1-4471-5191-3_15, © Springer-Verlag London 2013

Pseudotumor cerebri is also known as benign/idiopathic intracranial hypertension. Patients with pseudotumor cerebri are usually young, obese females, who may have a history of medication use including tetracycline, steroids, or vitamin A and its derivatives.

Symptoms and signs may include:

1. Generalized headache 2. Transient visual obscurations 3. Papilledema 4. Cranial nerve VI palsy (a nonlocalizing sign)

In pregnant or postpartum patients, the differential includes venous sinus thrombosis, which must be ruled out with an MRV.

There is signi fi cant risk of permanent loss of vision in untreated patients; therefore, it is practically a medical emer-gency and should be appropriately considered in the differen-tial diagnosis of headache.

Stabilize the Patient

ABCs

1. Assess the airway and breathing rate, and look for signs of respiratory distress.

Chapter 15 Pseudotumor Cerebri

118 Chapter 15. Pseudotumor Cerebri

2. Check the vital signs and assess if the patient is hemody-namically stable. Most patients will be stable.

Focused History

Take a focused history of the presenting symptom and onset.

Identify the Underlying Cause

Take Further History

1. Ask about the onset, frequency, and nature of head-aches and transient visual obscurations. Patients describe a dimming of vision which lasts for seconds and which occurs with change in position, especially on standing up.

2. Ask about the use of vitamin A and its derivatives (e.g., retinoids), tetracycline, and steroids.

3. Ask about associated conditions such as pregnancy, other hypercoagulable states, and sinus infections.

Do Examination

1. A complete neurological examination should be done. This includes testing mental status, cranial nerves, muscle bulk, tone, power, adventitious movements, deep tendon re fl exes, plantar responses, coordination with station and gait assessment, as well as sensory examination of all modalities.

2. Pay particular attention to papilledema (Fig. 15.1 ), enlarged blind spot, loss of the inferonasal visual fi eld, generalized constriction of the visual fi eld (in advanced cases), and cra-nial nerve VI palsy [ 1, 2 ] .

119Identify the Underlying Cause

Do Investigations

1. CT/MRI scan of head.

A CT scan of the head can be normal or show slit-like ventricles.

2. Lumbar puncture.

The opening pressure is elevated above 250 mm H 2 O, but the rest of the CSF analysis should be normal, with possi-ble exception of a low protein level [ 3 ] .

3. MRV.

Done to rule out venous sinus thrombosis in pregnant, postpartum, or other high-risk patients.

4. Formal visual fi eld testing is done to screen for and moni-tor any visual fi eld loss.

Figure 15.1 Grade III papilledema showing blurred disc margins and disc vessels obscuration by the nerve fiber layer. There are very prominent peripapillary nerve fibers (Courtesy of Dr. Lisa Lystad, Cleveland Clinic)

120 Chapter 15. Pseudotumor Cerebri

Treat the Underlying Cause

1. The offending agent should be stopped. 2. Weight loss is the mainstay of long-term management. 3. Acetazolamide 250 mg three times daily or furosemide

40–80 mg daily may be helpful [ 4 ] . 4. Patients may need a VP shunt. 5. Optic nerve sheath fenestration is indicated in refractory

patients.

Discussion

Untreated intracranial hypertension may result in permanent loss of vision due to compression of the optic nerve by increased intracranial pressure transmitted through the sub-arachnoid space.

References

1. Wall M, Hart Jr WM, Burde RM. Visual fi eld defects in idiopathic intracranial hypertension (pseudotumor cerebri). Am J Ophthalmol. 1983;96(5):654–69.

2. Rowe FJ, Sarkies NJ. Assessment of visual function in idiopathic intracranial hypertension: a prospective study. Eye (Lond). 1998;12(Pt 1):111–8.

3. Johnston PK, Corbett JJ, Maxner CE. Cerebrospinal fl uid protein and opening pressure in idiopathic intracranial hypertension (pseudotumor cerebri). Neurology. 1991;41(7):1040–2.

4. Wall M. Idiopathic intracranial hypertension. Neurol Clin. 2010;28(3):593–617.