Sunday 20 May 2012

Superficial Siderosis MRI T2*GRE Brain

Axial T2 *GRE images of brain reveals low signal intensity hemosiderin staining on surface of parietal lobes marked on right side suggestive of Superficial siderosis, not at all obvious on any other sequence. Axial FLAIR images in corresponding region normal. 
Superficial Siderosis

A rare condition characterised by abnormal hemosiderin staining of sub arachonid space, may be diffuse or focal, commonly overlying cerebral and cerebellar convexity, basal cisterns, ventral surface of brain stem on T2*GRE, results from excessive and repetitive subarachonid bleed.
An associated staining along cranial nerves particularly i, ii and viii CNs.
May see an associated atrophy of cerebellar hemispheres and vermis, lepto meningeal thickening with enhancement.
CT usually normal may show faint hyperdense layering.
Differential diagnosis is none, it has a pathognomonic appearace on T2*GRE.

Superficial siderosis is not a final diagnosis but an important finding indicating a remote or recurrent intra cranial bleed in subarachnoid space. Further imaging evaluation should be directed towards source of bleeding like MR Angiography to rule out aneurysm or any other vascular malformation.
The issue is cause of bleed. In ~25% cases cause in not found.

Clinically common symptoms are ataxia, hearing loss, anosmia, dementia; in long standing cases adjacent brain parenchymal atrophy ensues with altered cognition.
Treatment directed towards finding and removing cause of bleeding. Iron chelating agents.

Reference: Teaching atlas of brain imaging: By Nancy J. Fischbein, William P. Dillon, A. James Barkovich : Dural and lepto meningeal processes, Case 65, page  231.

To see another case of Superficial siderosis :
Case 1 : Click here
Case 2 : Click here


jon said...

GRE Classroom Session is the most comprehensive designed Test prep module Trump and Gates offers. The T & G Expert will work with the student to create a tutoring program that targets the weaknesses of the student and enable them to ensure their score. Our end goal is to make our students to get into top-choice business school.

nancy john said...

I'd even recommend some of the classic papers or surveys of classic papers as reading material over a general subject test.


nancy john said...

Gre exam is very important so students must keep in mind that only hardworking can help for passing it

study in usa