Art from Artifact

Beauty in the unexpected

In pathology, an artifact is an artificial change introduced as a result of some step in tissue manipulation. Tissue processing -progressive dehydration and paraffinization - produces reproducible "artifacts" as a result of inherent properties of some tissues lending their "classic" appearance under the microscope (e.g. "fried egg" appearance of oligodendrocytes, "orphan Annie-eye" nuclei in follicular thyroid carcinoma).  In general, though, artifact is something to be avoided -an unwanted result of some misstep in the tissue handing process...improper fixation, air drying, or the dreaded air bubble under the coverslip.  These artifacts can physically obscure the tissue and even alter the appearance of cells.  Sometimes the effect is small like tiny flecks of black formalin pigment in the background.  At its worst, artifact can make tissue sections nearly uninterpretable (e.g. cautery artifact or "cooked" tissue, ice crystals in frozen section).

As I was looking at sections of frontal cortex today for a research study, many of the slides had fallen victim to the plight of too little mounting medium causing air bubbles everywhere!! These bubbles produce black masses (highly refractile without the condenser) under the microscope obscuring the tissue beneath. As I was fighting with the bubbles, I began to notice the amazing arrangements they made as the air dissected along the tissue surface -these beautiful ice crystal-like organic structures forming tiny forests on the microscopic surface of neurons, glia, dendrites, axons, capillaries and arterioles...little rivers formed by negative spaces between gyri.

More strange little planets and unexpected landscapes.

Here's to finding the unexpected beauty in the artifacts of life.

 

Wriggly worm

Henry met his first earthworm today. The poor guy was wriggling on the doormat as we walked up to ring the doorbell at daycare. (sidenote: this is a common hazard of rainy Seattle weather as you often have to watch your step for beached worms). "We" placed him in the grass, rescuing him from almost certain demise. As we did, Henry tried out his new word, "wohm!".  When Faduma opened the door, he exclaimed "Wohm, Wohm!" and then said "Thank you, Mama!" ...and my heart melted.

That is all. Have a good night :)

Magpie in the house

Henry has turned into a regular magpie, pilfering and stashing treasures in all kinds of hidden places. Things mysteriously go missing and then I remember, "oh yeah, we have a toddler in the house".  Then it all makes sense in the way that toddlers make no sense at all, being the completely unpredictable creatures that they are. Latest missing item...my hairbrush. Eh well, that's what pony tails are for. Here's to life with silly toddlers and the magic they bring. Thanks for making our lives so interesting.

I love you my little magpie.

Up in the sky!

A little fun with toddler plane-spotting. Original photo courtesy of Dad.

Our son is obsessed with pointing out each plane that flies overhead. "MaHn!!", he exclaims. I'll always cherish those sweet first words.

Seas of pink

Diffuse, neuritic, dense core, fibrillary, primitive, compact, burned-out, cotton wool, fleecy, lakes -all ways to describe the morphologies of amyloid beta, the plaque-forming pathologic protein of Alzheimer's disease, in the brain. 

200X HE/LFB. Case with severe Alzheimer's pathology with back-to-back amyloid plaques comprising the majority of the field.  These dense, pink, fluffy spherical aggregates are surrounded by islands of vacuolated brain tissue with significant reactive astrocytosis (cells with plump, bright pink cytoplasm and visible processes).  

Reminds me of fluffy cotton candy...

Build a brain

Before we start, a little background...

At least 6 months of my second (and final) year of neuropathology fellowship focuses on the neuropathological work-up of dementia. The most common types we encounter are Alzheimer's disease, vascular dementia, and Lewy Body dementia; however, we have our fair share of other diverse entities including rare genetic disorders.

  

Our process involves soaking the brain in formalin fixative for at least 10 days to preserve the tissue. The brain is then embedded in a gelatin mold to stabilize the tissue for cutting into thin (3 to 4 mm thick), uniform sections. These sections are then laid out in order from front (anterior) to back (posterior) across several boards. 

The process of evaluating all aspects of the tissue that can be seen with the naked eye, followed by sampling of representative standard sections (those required to diagnose the three most common types of dementia noted above as well as other pathology) as well as any abnormal areas, is called gross examination or "grossing" the tissue.

4 mm thick coronal brain slices (anterior ~1/3 of right side of brain)

The sampled tissues are then processed, put onto glass slides, and stained for examination under the microscope. Sampling only accounts for probably ~5% of the brain tissue. Remaining tissues are stored in tidy glass jars as a part of our repository.

What happens if you have to go back to the previously cut and sampled brain? It is not infrequent in pathology that a specimen needs to be revisited for one reason or another in order to submit additional tissue. That is when the fun starts!

Previously sampled brain slices enjoy great freedom and entropy upon release from their jar.

For this particular case, I needed to re-examine possible lesions on the surface of the posterior, inferior frontal lobe and the posterior, superior temporal lobe. The best way to fully evaluate the surface again is to reconstruct the left half of the brain. Even though I only needed to put the anterior half together, I thought...why stop there? 

Reconstructed left half of brain (all cortical slices accounted for except for 3 overly fragmented slices)

I am in constant awe at the beauty of the human brain. Each case is a bit different and reveling in these structures never gets old.

I highly recommend reconstructing a brain to really hone your neuroanatomy skills! 

Cerebellum V1

Put a bird on it...

          

           Dark-eyed Junco atop cerebellar Purkinje cell dendritic arbor (Calbindin IHC, 200X)