Histopathologic and Cytologic Techniques Flashcards

Vocabulary practice flashcards covering histopathologic and cytologic techniques, specimen handling, fixation, decalcification, dehydration, clearing, infiltration, and embedding.

Excisional Biopsy

Surgical procedure involving the removal of the ENTIRE mass or organ.

Incisional Biopsy

Surgical procedure involving the removal of a PART of the mass or organ.

Fine Needle Aspiration Body (FNAB)

Procedure using a needle and syringe to obtain specimen cells, suitable for small and palpable lumps.

Core Needle Biopsy

Procedure that removes cells along with a small amount of surrounding tissue to assist in lesion examination.

Curettings

Procedure where tissue is scooped or spooned to remove tissue or growth from a body cavity such as the endometrium or cervical canal.

Rudolf Virchow Method

Autopsy procedure consisting of the removal of organs 1 by 1 done by 1 person.

Carl Rokitansky Method

Autopsy procedure featuring no removal and IN-SITU dissection.

Anton Ghon Method

Autopsy procedure featuring en-bloc removal of organs.

Maurice Letulle Method

Autopsy procedure featuring en-masse removal of organs at the same time.

Autolysis

The self-destruction of cells that occurs in living or fresh tissues.

Teasing / Dissociation

Fresh tissue examination method where tissue is immersed in isotonic salt solution in a Petri dish or watch glass and dissected with a needle.

Squash Preparation / Crush Technique

Fresh tissue examination method where small pieces of tissue (not more than 1 mm in diameter) are placed on a microscope slide topped with another slide or cover glass.

Touch Preparation / Impression Smear

Special fresh tissue examination method where the surface of a freshly cut piece of tissue is pressed onto a glass slide to transfer cells directly without destroying intercellular relationships.

Cryostat

Cold microtome enclosed in a cold chamber (-5 to -30 degrees Celsius, average 18 degrees Celsius) used for immediate tissue hardening and sectioning.

Accessioning

Process of recording the gross description of the specimen into a log book and specifying whether it is surgical, autopsy, or cytologic.

Autotechnicon

An automatic tissue processor capable of processing fixation, dehydration, clearing, and infiltration.

Fixation

Process involving the killing, penetration, and hardening of tissue to preserve morphology and cellular integrity.

Additive Fixative

Fixative agent that binds to tissue and forms cross-linking or molecular complexes that give stability to proteins.

Non-additive Fixative

Fixative agent that does not bind to tissue but stabilizes it by removing bound water attached to H-bonds.

Glyoxal

The smallest aldehyde fixative, which is fast-acting (4-6 hours for small tissues and 45 minutes for urgent biopsies).

Microanatomical Fixatives

Fixatives that preserve the microscopic anatomy of tissue without altering the structural pattern and normal intercellular relationship of the cell.

Nuclear Fixatives

Cytological fixatives with a pH of less than 4.6 containing glacial acetic acid.

Cytoplasmic Fixatives

Cytological fixatives with a pH of more than 4.6 without glacial acetic acid.

Secondary Fixation

Process of placing an already fixed tissue into a second fixative to improve demonstration of substance or ensure complete hardening.

Post-Chromatization

Form of secondary fixation using 2.5-3% Potassium dichromate for 24 hours for better staining and cytologic tissue preservation.

Washing Out

Removal of excess fixative from tissues following fixation using tap water, 50-70% alcohol, or alcoholic iodine.

Decalcification

Removal of calcium ions or lime salts from the organic extracellular matrix, calcified collagen, and surrounding tissues of bones.

Electrolytic Method

Decalcification method based on the principle that positively charged calcium ions are attracted to negative electrodes from the decalcifying solution.

Ion Exchange Resin Method

Decalcification process using an ammonium form of polystyrene resins and formic acid.

Chelating Agent

Decalcifying agent such as EDTA (14%, pH = 7.76) that binds with calcium to form weakly dissociated complexes.

Calcium Oxalate Test

Chemical method to determine the end-point of decalcification by adding strong ammonia and ammonium oxalate to discarded fluid.

Dehydration

Removal of intercellular and extracellular water from tissues after fixation using increasing concentrations of alcohol.

Clearing

Also known as dealcoholization; process of removing dehydrating agent from tissues to replace it with a medium miscible with paraffin wax and mounting medium.

Infiltration

Also known as impregnation; process of removing clearing agent to fill up tissue spaces.

Carbowax

A polyethylene glycol water-soluble wax solid at room temperature that eliminates the need for dehydration and clearing.

Embedding

Also known as casting or blocking; process of placing infiltrated tissue in an embedding mold with melted medium to solidify into a tissue box.

Leuckhart's Embedding Mold

Non-disposable embedding mold consisting of two L-shaped blocks made of brass or metal.