Wednesday 29 January 2014

IDIOPATHIC INTRACRANIAL HYPERTENSION

IDIOPATHIC INTRACRANIAL HYPERTENSION:


 Figure 1: showing increased fluid in sheaths surrounding optic nerves along with tortuosity of the sheaths
 Figure 2: showing flattening of posterior sclera
Figure 3: Sagittal T2 WI showing a partially empty sella

The above pictures are of a 35 year old female who presented with headache and progressive visual loss.

MRI of the brain and orbits showed a partially empty sella, dilated/ tortuous optic nerve sheaths along with posterior scleral flattening. 
There was no evidence of an intracranial mass/ space occupying lesion or dural sinus thrombosis.

IDIOPATHIC INTRACRANIAL HYPERTENSION( IIH):
Also called pseudotumor cerebri.
As the name implies,the intracranial pressure is raised with no obvious underlying pathology in the brain.
Most common clinical presentation is an obese female aged 20-40 years with headache( aggravated by Valsalva), papilledema, progressive visual loss, diplopia etc.
MRI reveals a partially empty sella, optic nerve sheath dilatation with vertical tortuosity, optic nerve head protrusion and scleral flattening.
The diagnosis is made after other potential causes of raised intracranial hypertension like dural sinus thrombosis, space occupying lesion are excluded.
Aim of treatment is to prevent visual loss which is a potential danger from chronic papilledema.

REFERENCES:
  1.  Suzuki H, Takanashi J, Kobayashi K et al: MR Imaging of Idiopathic Intracranial Hypertension. AJNR 22:196-199, 2011
  2. Hingwala DR, Kesavadas C, Thomas B et al: Imaging signs in idiopathic intracranial hypertension: Are these signs seen in secondary intracranial hypertension too? Ann Indian Acad Neurol 16(2):229-233, 2013
  3. Castillo M: Idiopathic Intracranial Hypertension. Diagnostic Imaging Brain: First Edition. Amirsys: I-10-36, 2005.