Gross Techniques In Surgical Gross Techniques In Surgical PathologyPathology

IntroductionIntroduction

The routine work associated with a surgical The routine work associated with a surgical pathology specimen includes gross & pathology specimen includes gross & microscopic examinationsmicroscopic examinations..

Gross examinations give an idea about Gross examinations give an idea about size ,shape of specimen &any gross size ,shape of specimen &any gross abnormality like ulceration, nodularityabnormality like ulceration, nodularity..

The dissection, gross description &selection The dissection, gross description &selection of sections for microscopic study is a of sections for microscopic study is a crucial part of pathologic examinationscrucial part of pathologic examinations

Preparations of sections for Preparations of sections for histopathologyhistopathology

11 - -paraffin embedding method ( the routine paraffin embedding method ( the routine & widely used procedure)& widely used procedure)..

22 - -frozen section (intra-operative)frozen section (intra-operative)..

33 - -cytological diagnosis (exfoliative & fine cytological diagnosis (exfoliative & fine needle aspiration cytologyneedle aspiration cytology..

44 - -digital pathology & telepathologydigital pathology & telepathology..

Paraffin embedding methodParaffin embedding method

Include the following principle stepsInclude the following principle steps::

11-- fixationfixation:- :- to preserve the tissue, to preserve the tissue, fixatives include formaldehyde, Zenker’s fixatives include formaldehyde, Zenker’s solution, picric acid, Bouin’s solutionsolution, picric acid, Bouin’s solution,,

The best fixative is 10% buffered formalinThe best fixative is 10% buffered formalin

Advantages of FormalinAdvantages of Formalin

11 - -cheepcheep..22 - -always availablealways available..

33 - -good penetration into tissuegood penetration into tissue..44 - -cause little shrinkagecause little shrinkage..

55 - -preserve RBCs & fatty tissuepreserve RBCs & fatty tissue..66 - -special stains can be used on tissues special stains can be used on tissues

fixed with itfixed with it..77 - -preserve color of the tissuepreserve color of the tissue..

88 - -good hardeninggood hardening..

Disadvantages of FormalinDisadvantages of Formalin

11 - -if tissue preserved in formalin for long time, if tissue preserved in formalin for long time, formic acid will be formed which affect formic acid will be formed which affect stainability of tissue with different stains, so it stainability of tissue with different stains, so it should be changed every 3-6 monthsshould be changed every 3-6 months..

22 - -when formalin solution is stored for long period when formalin solution is stored for long period a white precipitate of para formaldehyde which a white precipitate of para formaldehyde which will not affect the efficiency of formalin as a will not affect the efficiency of formalin as a fixative & can be removed by alcoholfixative & can be removed by alcohol..

33 - -cannot preserve glycogencannot preserve glycogen..

22 - -DehydrationDehydration:-:- by using by using different different concentrations of alcoholconcentrations of alcohol..

33 - -ClearingClearing:- :- by using xylineby using xyline..

44 - -Paraffin impregnationParaffin impregnation..

55 - -EmbeddingEmbedding:- :- to make the tissue as a to make the tissue as a block of hard paraffinblock of hard paraffin

66 - -SectioningSectioning:- :- by using a microtome, the by using a microtome, the tissue is sliced into very thin sections ranging tissue is sliced into very thin sections ranging from 4-6 micrometer in thicknessfrom 4-6 micrometer in thickness..

77 - -Attaching sections to the slidesAttaching sections to the slides..

88 - -DeparaffinizationDeparaffinization:- :- by using xylol & by using xylol & alcohol until the paraffin is dissolvedalcohol until the paraffin is dissolved..

99 - -StainingStaining:- :- the standard staining method is the standard staining method is H & E which stain the nucleus blue (basophilic) H & E which stain the nucleus blue (basophilic) & the cytoplasm pink-red (acidophilic)& the cytoplasm pink-red (acidophilic)..

1010 - -MountingMounting:- :- by using DPX &cover slipby using DPX &cover slip..

Special Techniques In Surgical PathologySpecial Techniques In Surgical Pathology

11 - -Special stains like PAS (periodic acid schiff) stain, Gram, Special stains like PAS (periodic acid schiff) stain, Gram, Giemsa, Ziel-NeelsonGiemsa, Ziel-Neelson..

22 - -Enzyme histochemistryEnzyme histochemistry..33 - -Tissue culturingTissue culturing..

44 - -HistometryHistometry..55 - -X-ray microanalysisX-ray microanalysis..66 - -Electron microscopyElectron microscopy..

77 - -Immunohistochemistry, sensitive &specificImmunohistochemistry, sensitive &specific..88 - -Flow cytometryFlow cytometry..

99 - -CytogeneticsCytogenetics..1010 - -Polymerase Chain Reaction (PCR)Polymerase Chain Reaction (PCR)..