Histology

Permanent Mounting

1. HISTOLOGY TECHNIQUES
PERMANENT MOUNTING
BY
SYEDA SADAF WAJAHAT

2. introduction
❖Histologyalsoknownas“Microanatomy”is
thestudyofcells,tissuesandorgansunder
themicroscope(Lightmicroscopeor
Electronmicroscope).
❖ItisrelatedtoCellbiology(Cytology),
Anatomy,PhysiologyandPathology.

4. Types of tissueS

5. Types of tissueS

6. SOURCES OF SPECIMEN
❖Specimensreceivedforhistological
examinationmaycomefromanumberof
differentsources.
1.Excisionspecimens(surgicalbiopsies),
wherewholeorgansoraffectedareasare
removedatoperation.

7. 2.Incisionalbiopsyspecimens,wheretissueis
removedfordiagnosisfromwithinanaffected
area.
3.Punchbiopsies,wherepunchesareusedto
removeasmallpieceofsuspicioustissuefor
examination(oftenfromtheskin).

8. 4.Shavebiopsies,wheresmallfragmentsof
tissueare“shaved”fromasurface(usuallyskin)
5.Curetting,wheretissueisremovedinsmall
piecesfromtheliningoftheuterusorcervix.
6.Corebiopsies,whereasmalltissuesampleis
removedusingaspecialneedlesometimes
throughtheskin(percutaneously).

9. PERMANENT MOUNTING
❖Inhistologyorapathology,mountingisthe
lastprocedureintheseriesthatendswitha
permanenthistologicalpreparationonthe
table,wellafterthetissueprocessingand
staining.

10. PROCEDURE

12. PROPERTIES OF AN IDEAL
MOUNTING MEDIA
❖Refractiveindex(RI)shouldbeascloseas
possibletothatofglass,i.e.,1.5.
❖Itshouldbecolorlessandtransparent.
❖Itshouldbedrytoanon-stickconsistency
andhardenrelativelyquickly.

13. ❖Itshouldbeabletocompletelypermeate
andfilltissueinterstices.
❖Itshouldhavenoadverseeffectontissue
components.
❖Itshouldberesistanttocontamination.

14. CLASSIFICATION OF
MOUNTING MEDIA
❖There are two types of mounting medium.
1.Resinous media (hydrophobic/adhesive).
2.Aqueous media (hydrophilic/non-adhesive).

15. 1. Resinous MEDIA
(hydrophobic/adhesive)
❖Thesearenaturalorsyntheticresins
dissolvedinbenzene,tolueneorxylene.
❖Usedwhenapermanentmountisrequired.

16. ❖Adhesiveshardenthroughsolvent
evaporationandtherebyfixthe
accompanyingcoversliptotheslide.
❖Resinousmountantsarethetypemost
frequentlyused.
❖Itisfurtherdividedinto

17. 1.NaturalresinousmedialikeCandida
Balsam,PhenolBalsamandDammar
Balsam.
2.SyntheticresinousmedialikeDPX
(dibutylphthalateandxylene),Permount
andHistamount.

19. 2.AQUEOUS MEDIA
(HYDROPHILIC/NON -
ADHESIVE)
❖Aqueousmediaareusedformounting
sectionsfromdistilledwaterwhenthestains
wouldberemovedbyalcoholandxylene.
❖Thesemediaareofthreetypes:Thesyrups,
GelatinmediaandGumArabicmedia.

20. ❖Aqueousmountingmediarequirethe
additionofbacteriostaticagentssuchas
phenolorcrystalofthymoltopreventthe
growthoffungi.
❖ExamplesareWater,Glycerinejelly,
Glycerine-GlycerolandPolyvinylalcohol.

21. ❖Therearemanycommercialmountingmedia
whichareavailableformountingsectionsfrom
water.

22. PREPARING PERMANENTLY
MOUNTED SECTIONS
❖Place2-3dropsofresin(mountingmedia)
overthesection.
❖Toavoidentrappingairbubbles,lowerthe
coverslipslowlyfromonesideofthedroplet.

23. ❖Placetheslideontheslidewarmerand
carefullyplacealeadweightontopofthe
coverslip.
❖Leaveslidesonthewarmer
foratleast24hours.

24. ❖Observethetissuesectionunderthe
microscope.

25. CONCLUSION
❖Toconcludevariouscommercial
manufacturershavevariousmounting
media.Youshouldselectamountingmedia
thatsuitstheviewingandpreservingthe
requiredsectionsforfurtherresearch.