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Problems and "Did You Knows" in Histopathological Technique
PROBLEM NUMBER 1
Grid-like impression artefact in small biopsies after using sponge
pads to hold biopsies during processing
PROBLEM NUMBER 2
Using Calcium Carbonate to neutralise formalin
PROBLEM NUMBER 3
To obtain a section from tissues which are hard to cut after
conventional fixation and processing
PROBLEM NUMBER 4
Fragmented, crushed and overstained sections from small biopsies
PROBLEM NUMBER 5
Finding a minute biopsy after processing
PROBLEM NUMBER 6
Shattering, cracked or folded sections from large blocks processed
through paraffin wax
PROBLEM NUMBER 7
Recovering tissue that has dried out after a malfunction of a tissue
processor
PROBLEM NUMBER 8
To obtain a section from tissues which are often brittle after
processing
PROBLEM NUMBER 9
Crooked or uneven ribbons when sectioning
PROBLEM NUMBER 10
Wrinkled or compressed sections
PROBLEM NUMBER 11
Wrinkles appearing in sections floated on a flotation bath
PROBLEM NUMBER 12
Cutting thick and thin sections
PROBLEM NUMBER 13
Sections adhering to the block on the upstroke of the microtome
PROBLEM NUMBER 14
Ribbons split vertically or scratch lines appearing in a section
PROBLEM NUMBER 15
Sections crumble or tear
PROBLEM NUMBER 16
Cutting thick and thin within a section due to a minute high pitch
vibration in a knife edge (chatter)
PROBLEM NUMBER 17
Sections will not ribbon
PROBLEM NUMBER 18
Sections roll up when cut
PROBLEM NUMBER 19
Sections disintegrate on the water bath
PROBLEM NUMBER 20
Sections appear chalky white on flotation
PROBLEM NUMBER 21
To restore good nuclear staining to tissue sections exposed to
over-fixation in neutral buffered formalin
PROBLEM NUMBER 22
Smudgy or unusual staining when using hand staining or an automatic
staining machine
PROBLEM NUMBER 23
How to restore good nuclear staining to tissue sections which have
been exposed to over-fixation or over-decalcification
PROBLEM NUMBER 24
To destain a slide to be stained by another technique
PROBLEM NUMBER 25
Inadequate staining and/or leeching of eosin from tissue sections
after washing and before dehydrating
PROBLEM NUMBER 26
A diffuse staining of all tissue structures with Schiff reagent
following fixation of the tissue with glutaraldehyde containing
fixatives
PROBLEM NUMBER 27
Muddy background staining when using Verhoeff's elastic stain with a
Van gieson counterstain
PROBLEM NUMBER 28
Staining of crystalloid mucoid material on the surface of sections
or smears where the tissue has a high mucin content
PROBLEM NUMBER 29
Poor staining or lack of staining with Alcian Blue dissolved in
acetic acid
PROBLEM NUMBER 30
To remove a coverglass from a slide more than 20 years old
PROBLEM NUMBER 31
Cleaning hardened paraffin wax off benches and embedding centres
PROBLEM NUMBER 32
Cells in stained tissue sections appearing crenated
PROBLEM NUMBER 33
To recover sections from broken slides
PROBLEM NUMBER 34
Plastic coverslip tape lifting from a glass slide
DID YOU KNOW NUMBER 1
That Hyaluronic acid cannot be demonstrated after tissue is fixed in Zenker or Bouin's fluids?
That during fixation woth compound fixatives the most rapid penetrator will determine the fixation image because penetration is determined by the law of diffusion?
That pseudocalcification artefacts are seen when calcium acetate or carbonate are used to neutralise 10% formalin or when any calcium salts are used in compound fixatives
That zinc chloride can be substituted quite successfully for mercuric chloride in compound fixatives where the formula reuires mercuric chloride?
That picric acid is highly explosive in the dry state?
That the pH of tissue and nuclei within the body is within the range 7.6 to 7.8?
That most tissue shrinkage is not caused by fixation but by subsequent dehydration and clearing?
That tissues which are placed directly into 100% Ethyl alcohol from a fixative undergo considerably more shrinkage and distortion than tissues which progress through a series of more dilute alcohols such as 70%, 80% and 90%?
That in these days of tightening budgets silica gel can be used to remove water from most dehydrants and so prolong their useful life?
That tissues labelled as left and right can be processed and cut together?
That a highly polished bevel on a knife is more important to cutting good sections than sharpness?
That bone specimens can be processed undecalcified and then surface decalcified in 10% hydrochloric acid for 15 minutes before cutting. Calcified specimens are thus available more quickly for diagnosis, and staining is almost always better than if the bone is first decalcified?
That nucleoli stain blue after Zenker fixation?
That after adding 5gm of copper (shot) metal to the protargol solution in Bodian's technoque for nerve fibres and nerve endings the quality of the result is considerably improved?
That it is almost impossible to restore good nuclear staining characteristics after tissues have undergone autolysis before fixation?
That when solutions are heated in a microwave for fixation or staining there can be a marked difference in temperature between the top and bottom layers of the solution?
That using tap water to dilute nitric acid may cause the solution to explode because of contaminants in the water?
That adding Ethyl alcohol to a solution containing chromic acid and mercuric chloride can cause spontaneous combustion?
© Roy C. Ellis 2002