Aneurysm COW

MRA's of the brain are done for cerebral aneurysms.Some patients with acute ruptures present with a stabbing headache out of nowhere.  Others present with history of headaches in particular areas, eye pain, pulsing or family history of aneurysm.  Sometimes larger aneurysms can be harder to see on MR due to the fact of getting lack of flow in the bulb of the aneurysm.  If flow in the aneurysm is not flowing frequent enough it will not show up on the MRA as well due to the nature of the imaging.  Since brain MRA's are usually done non contrast, this can make a diagnosis difficult.  If a patient has an aneurysm they will usually require surgery and have a coil or clip placed to stop the progression and the possibility of rupture. The following website has great information regarding the whole aspect of cerebral aneurysms:  http://www.ninds.nih.gov/disorders/cerebral_aneurysm/cerebral_aneurysm.htm

The following images are of a middle cerebral brain aneurysm:

Cavernous Sinus Fistula

A cavernous sinus fistula happens when the internal and external carotid arteries and the cavernous sinus gets their "communication" mixed up.  These patients usually see an eye doctor first with eye pain or proptosis.  Sometimes these happen spontaneously but more often by trauma.  A usual protocol for our facility would be images of the entire brain,but also including:
Pre-contrast of orbits

• T1 fatsat coronal      
•  T1 Axial 
•  thin slice Cor T2 

Post contrast of orbits:

• Fat sat Axial T1
• Fat sat Cor T1
• Fat sat Sagital Oblique (angled with optic nerve) of both orbits

The following web site has some basic information:  http://emedicine.medscape.com/article/1217766-overview

The following images are from a patient with a cavernous sinus fistula right side seen posterior orbit cavity.  You can also see the proptosis in the right eye compared to the left.

T2 Axial

T2 coronal

T1 axial

T1 axial post contrast fatsat

T1 Sagital oblique post contrast fatsat



Pituitary Microadenomas MRI

Micoradenomas, on MRI imaging, can be seen best by using a pre and post contrast gadolinium enhanced study detailed to the pituitary gland.  Dynamic imaging of the pituitary gland can increase the sensitivity of seeing the microadenoma in some instances.  This article shows some studies related to the sensitivity and specificity of the dynamic imaging.  http://www.endocrinology.org/education/resource/summerschool/2004/ss04/ss04_byr.htm
Many of these patients will present with some kind of metabolic or hormonal imbalance, including, but not limited to:  absence of menstruation, lactating breast, breast development in males, any many other hormone regulated problems.  I have included some imaging of a patient with a microadenoma on the right side of the patients pituitary gland, displacing the infundibulum slightly to the patients left.  I have also included a dynamic image showing the actual absence of contrast enhancement as the pituitary gland enhances.

T1 Coronal pre contrast

T1 Coronal post contrast

T1 Sagital pre contrast

T1 Sagital post contrast

Dynamic Coronal about 30 seconds post injection