Another interthalamic adhesion picture

This is a high-power picture of the interthalamic adhesion of an 81-year-old man with a clinical diagnosis of Dementia with Lewy Bodies. Again, see the collection of neuron cell bodies along with glial cells. I should remind you that not everyone has an interthalamic adhesion (about 20% are lacking this grey matter), and women are more likely to have this structure than do men. Nobody knows why this is, or what the function of the structure is. I supporse there are two possibilites, either it is of no practical importance, or there is an alternative way in which those lacking an interthalamic adhesion can process the information otherwise reserved for this structure.

Erratum regarding the interthalamic adhesion

I must revise a post from May 19, 2008 in which I quoted Dr. George R. Leichnetz, neuroanatomist at Virginia Commonwealth University and author of Digital Neuroanatomy: An Interactive CD Atlas with Text (Wiley-Liss, 2006). At that time, Dr. Leichnetz emailed me the following: “The 'interthalamic adhesion' or 'massa intermedia' is (as its name implies) an adherence of the ependymal lining of the midline third ventricle. Importantly, it is not a commissure, ie. there are no inter-thalamic fibers exchanged between the two thalami."

At that time, I said that I would confirm this view under the microscope by taking some sections of the interthalamic adhesion at autopsy. Well, it turns out that there are plenty of neuron cell bodies and nerve tracts within the massa intermedia. Above is pictured the massa intermedia from an 85-year-old lady with Alzheimer disease. Notice the bipolar neurons, particularly convincing is the neuron with the prominent nucleolus. Since this slide was stained with luxol fast blue, which stains myelin blue, you can see that there are indeed nerve tracts running through the massa intermedia. As I did further research on the internet, I found a consensus that the massa intermedia is indeed grey matter, and not simply an adherence of ependymal lining as was stated by Dr. Leichnetz. Sorry about any confusion I may have caused regarding this matter.

Estelle Getty suffered from Lewy Body Disease

Here's an article describing today's passing of Estelle Getty, 'The Golden Girls' actress.

There's money in blogging!

The esteemed Dr. Doug Shevlin fowarded me this New York Times article about another guy with an M.D. after his name who blogs. Dr. Arnold Kim, pictured above, writes MacRumors.com, which monitors new developments coming out of the notoriously secretive Apple. Dr. Kim recently quit his day job as a physician, which brought in a six-figure income, to blog full-time, saying "“on paper, it was an easy decision.” Sweet.

Best Post of March, 2008: A new disease which lawyers love

The next in my occasional "Best of the Month" series goes back to March '08 with this post:

Neuropathologists are always reviewing brain MRIs that use gadolinium contrast. I never thought much about the potential toxic effect of gadolinium. However, the illustrious Dr. Brajesh Argawal, resident in the Southern Illinois University School of Medicine neurology program, informed me yesterday of the risk of the use of gadolinium-based MRI contrast agents in patients with chronic renal failure. There is an emerging disorder, known as nephrogenic systemic fibrosis (NSF), that can arise in these patients. NSF involves the deposition of collagen in the skin and other organs in patients either on dialysis or with a glomerular filtration rate of less than 15 cc/min. According to an article on the topic by Philip Kuo et al. in the journal Radiology (2007;242:647-649), “NSF may develop rapidly and can sometimes result in patients becoming confined to a wheelchair within a few weeks… While NSF sometimes stabilizes, it rarely spontaneously remits.” Malpractice lawyers are, of course, all over NSF. For instance:
http://www.mri-contrast-lawsuit.com/

Radiologists now make it a practice to have patients sign a consent form which mentions the possibility of the development of NSF in those with renal insufficiency. Here’s a link to the FDA alert concerning gadolinium:
http://www.hpcbd.com/FDA%20Gadolinium%20Alert.pdf

Thanks for the information, Dr. Argawal!

'Moore as Lincoln' back in Profile

By popular demand, I have removed the respectable and professional picture on my profile and replaced it with me dressed as Abe Lincoln last February 12th.

A New Prion Disease

The esteemed Dr. Doug Shevlin (pictured on left) sent me this article on a newly described prion disease known as protease-sensitive prionopathy (PSPr), a disease with a similar clinical presentation as sporadic Creutzfeldt-Jakob disease (sCJD), but with a stronger hereditary connection. The prions associated with sCJD are protease resistant, but (as the name indicates) this new prion disease is caused by proteins that are protease sensitive. The authors, Pierluigi Gambetti and colleagues at the National Prion Surveillance Center in Cleveland, conclude that PSPr "is not rare among prion diseases, and it may be even more prevalent than our data indicate because protease- sensitive prionopathy cases are likely also to be classified within the group of non-Alzheimer's dementias."