Histopathology Theory

Preservation of tissue preventing autolysis and putrefaction

Enables proper tissue staining

Buffered with Sodium dihydrogen phosphate monohydrous and Disodium hydrogen phosphate anhydrous

Lily's, Kardasiwiths and Picric Acid Method

Soak in picric acid for 5 minutes to 2 hours then wash for 10-15 minutes

A staining method using glacial acetic acid and absolute ethanol, which shrinks and hardens tissues due to alcohol's dehydrating nature. This method focuses on cellular structure.

Similar to Carnoy's, this method uses glacial acetic acid and absolute ethanol to shrink and harden tissues. It's specifically designed for studying cell structures.

This method utilizes potassium dichromate and mercuric chloride to dissolve lipids and focus on cell cytoplasm. However, mercuric chloride is toxic, and formain pigment might form as a result.

Both methods employ alcohol, resulting in tissue shrinkage and hardening. This effect is due to the dehydrating properties of alcohol.

Helly's Method uses mercuric chloride, a toxic substance. This compound can lead to the formation of formain pigment during the staining process.

A cytological fixative that preserves nuclear structures well. It contains picric acid, which gives tissues a yellow color and destroys red blood cells.

A component of Bouins fixative. It forms a yellow compound with proteins, making tissues appear yellow. It's explosive when dry, so it must be stored submerged in water.

Bouins fixative contains picric acid, which destroys red blood cells. This is why it's not suitable for studying blood cells.

A microanatomical fixative that preserves tissue structures well. It contains chromic acid.

A component of Zenkers fixative. It helps preserve tissue structure.

The process of removing calcium from tissues, like teeth and bones, using chemicals. It prepares tissue samples for examination under a microscope.

Decalcifying tissues makes them easier to cut into thin slices for examination under a microscope. This is essential for studying their internal structures.

A good decalcifier should remove calcium quickly without damaging the tissue or affecting the staining process. It should preserve the original structure of the tissue.

A good decalcifier shouldn't interfere with the staining process. Staining helps visualize different structures within the tissue.

While an ideal decalcifier removes all calcium, it's crucial to ensure the tissue's integrity is not compromised. Sometimes, a little calcium might remain to protect the tissue structure.

The process of removing calcium from bone tissue, primarily to prepare it for microscopic examination.

Decalcification makes bone tissue softer and easier to cut into thin slices for microscopic analysis.

The completion of decalcification is confirmed when the solution remains clear and the test with red litmus and ammonium solution turns blue.

If the solution remains cloudy or turbid after 30 minutes, decalcification is incomplete, meaning more time or adjustments to the procedure are needed.

Neutralization is crucial to remove excess chemicals used in the decalcification process, ensuring no harm to the tissue.

A decalcification method that uses acids to dissolve calcium salts into a soluble form.

Acid Decal is fast and affordable compared to other methods.

Acid Decal can damage tissue and weak acids take longer to work.

A decalcification method that uses a resin to remove calcium ions from the tissue.

A decalcification method that uses electricity to remove calcium ions from the tissue.

A method using resin to remove calcium ions from tissue. It's slower than acid decalcification but preserves the tissue's morphology.

A method using electricity to remove calcium ions from tissue. It's fast but requires special equipment and can shrink tissues.

A method using strong acid to remove calcium quickly but can cause over-decalcification and produce fumes.

Preserves tissue morphology and is faster than using weak acids for decalcification.

Requires special equipment and can cause tissue shrinkage.

A rapid decalcifier containing hydrochloric acid. It's easy to use but can produce fumes and potentially over-decalcify tissue.

Uses chromic and nitric acids, ideal for preserving small bones and cellular detail. Produces good staining results.

A decalcifier that contains ammonium citrate and citric acid. It's good for staining, but too slow for routine decalcification.

ROO decalcifier is rapid, meaning it works quickly, and it's easy to use. It's well-suited for routine decalcification processes.

ROO decalcifier produces fumes, which can be harmful, and it can over-decalcify the tissue, damaging its structure.

A fixative solution composed of acetic acid and chloroform, used for preserving tissue samples.

A fixative solution containing formic acid and formaldehyde, used for tissue preservation.

Minimal tissue damage compared to other fixatives.

A good fixative preserves tissue structure without causing significant damage.