Monday, August 11, 2008

Microscopic world

I am always fascinated with what I see in a hematoxylin and eosin (H&E) stained histopathologic slide under a light microscope.

Eventhough the denizens of the microscopic world were already dead by the time I examined the slide, I still appreciate what a wonderful world it must have been for the cells, extracellular fluid, connective tissue, capillaries, the various chemicals that make the world go around as it should.

I remember as a budding histopathologist, more often that not, I described everything that I saw, even the normal and the within-normal findings.

"You have to know the normal first before you would be able to catch the abnormals - the lesions." Those were the words of Prof. Sheikh Omar, my pathology mentor whom I shall be forever thankful.

Describing the changes is both a sceince and an art. Without the art part, descriptions would be dull and monotonous. Language plays a vital role in describing microscopic changes, both to the describer and also to the reader. The style changes with different reader in mind.

Till now I do not know and never ask anybody the reason why we use present tense in describing microscopic changes and past tense for gross pathology. I guess it is just the way they were used to.

Evaluation of tissue slides should always follow a certain way. This is to ensure that nothing is left behind. As an example let us take a piece of bovine lung (a fancy way of saying a cattle's lung).

Try to minimise words that we use. Avoid redundancies - like red in colour (red is red). Use full grammatical sentences. I love to use beautiful English when I describe things.

Instead of saying: There are bacteria on the intestinal mucosa, I would rather say: Intestinal mucosa is lined by clouds of Gram positive bacilli.

Instead of saying: There are numerous foci of micro-abscesses in the spleen, I would rather say: The splenocelluar architecture is effaced by numerous micro-abscesses and so on and so forth

I prefer examining it from the airways outwards - the alveoli, bronchioles, bronchi, interstial tissues, blood vessels and finally the pleura.

Alveoli are normally lined by simple squamous epithelial cells - these are normally not readily seen unless disturbed. When you see cells are stacked in layers, you know that there is something wrong with them.

Alveolar spaces of a healthy cow is normally filled with just air - nothing should be in it. If it is pneumonia there would be neutrophils, both living and degenerate, may be macrophages - single or multi-nucleated (depending on the causative agents).

After seeing and noting down all the changes, finally I draw up the most appriopriate morphologic diagnosis. For example: Pyogranulomatous bronchointerstitial pneumonia with intralesional fungal hyphae...I usually shorten the usually long A.F.I.P's (Armed Forces Institute of Pathology) morphologic diagnosis...

That is enough I think. I am not going to bore you with all these histopathologic terms. What I want to get to is behind all these microscopic world - there is the Creator.

It is illogical that all these well-planned activities happen by themselves, so perfect. Just take a second and ponder on this point.

1 comment:

student microscopes said...

It is always fun and exciting to see those wonderful microscopic creatures in microscopic world..