DX: Olfactory groove meningioma

This case shows some of the peculiar imaging characteristics of a Meningioma. It was hyperdense on CT post contrast, T1 and T2 iso-hyperintense, and hyperintense on FLAIR images with avid enhancement on post Gad. It had a dural based tail and showed a falx calcification. It was located in the orbitofrontal region just above the cribiform plate and near the midline. It had vasogenic edema.

Here are the images:

Although the tumor is small in size it provoked considerable presence of edema that probably caused symptoms. These symptoms were vague with components of a frontal lobe disorder that could explain changes in personality. There was no Anosmia that could lead us to the specific location of symptoms. But current literature says that symptoms may vary in this condition. This tumor is benign but has great growing potential so diagnosis is crucial.

Olfactory groove meningiomas arise over the cribriform plate and can be differentiated from tuberculum sellae meningiomas because olfactory groove meningiomas arise more anterior in the skull base and displace the optic nerve and chiasm inferiorly rather than superiorly. Although these tumors arise in the midline, they may extend predominantly to one side like this case. It can also be very atypical in presentation with restricted DWI.


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http://www.medscape.com/viewarticle/457741
http://radiopaedia.org/cases/olfactory-groove-meningioma
http://www.neuroradiologycases.com/2011/10/olfactory-groove-meningioma.html

CASE 34: 43 y/o male with altered mental status

Patient had altered mental status mainly behavioral changes and abnormal hesitation in regular activities. CT scan was abnormal but inconclusive. There was a focal hypodensity  in right frontal lobe but with no ischemic characteristics. Rest was unremarkable. We did a contrast enhanced CT scan to see if it showed an abnormality.

Here are the relevant images of the contrast enhanced CT scan:

With a diagnosis in mind, we conducted an MR:

Axial FLAIR

T1 coronal post gad

Pretty clear diagnosis. Findings?...later, the conclusion.

DX: Venous angioma (Developmental Venous Anomaly, DVA)

In the images, we see a "tunnel-like" flow void in left parietal region that apparently has cortical origin. It enhances with Gadolinium but has a unique morphology. On it's tip, we see a capillary nidus that resembles the head of a medusae or an umbrella. This is consistent with a particular Arterio-venous Marlformation type that mostly consists of enlarged anomalous veins called Venous Angioma.

A venous angioma, also referred to as a "developmental venous anomaly" (DVA) or sometimes "venous malformation" is basically an extreme variation of veins draining normal brain tissue in that region. That is, a venous angioma (DVA) by itself isnot necessarily "abnormal"; it's rather a variation of normal. However, having stated this, it should be noted that some studies have found that some veins (or all veins) that comprise a venous angioma have structural abnormalities compared with more normal veins. Regardless, most neurosurgeons regard venous angiomas by themselves as extreme variations of normal venous drainage.

The veins that comprise a venous angioma usually form a little cluster ("star burst" or "caput Medusae" - looks like a "head of snakes"), and these veins generally drain into a larger "collector" vein. The collector vein is usually on the surface of the brain, but sometimes there may be deep drainage too. The pattern (arrangement) of these veins is frequently simple, but may at times be more complex looking. Between the veins that make us the venous angioma is normal brain tissue. Sometimes one or more of these veins can appear extra dilated and may be more thin walled than other veins in the brain. Venous angiomas tend to occur near the frontal horns of the ventricles (fluid filled spaces of the brain) and also in the cerebellum (small part of the brain at the lower back part of the head).

Importantly, venous angiomas are frequently associated with cavernous malformations (cavernomas) and it is through this association that trouble potentially arises. Venous angiomas on their own don't tend to cause any trouble and, with few (reported) exceptions, should generally be left alone like this case.

Thank you Dr. Rammohan Vadapalli, Hitender Himral, Ruchi Gupta, Mayur Kulkarni for your great comments on FB groups!

Until next time.

http://journal.nzma.org.nz/journal/120-1250/2449/

http://www.brain-aneurysm.com/dva.html

http://www.mayfieldclinic.com/PE-AVM.htm

http://radiopaedia.org/cases/venous-angioma

CASE 33: Female 38y/o patient with intermitent headache

This was an outpatient with history of intermitent and refractary headaches over the past 5 years. She had no history of diseases, medications, or previous trauma. CT scan (not shown) performed in other center was apparently normal but neurologist wasn't satisfied with it. 

Here are the relevant images:

Thank you to TecniScan Diagnostic Center here in Guatemala city for providing me with these case.

Findings?

Later, as always..the conclusion.