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Museum techniques

by mr rupesh giri nepal

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Museum techniques

  2. 2. MUSEUM  A place to exhibit objects  An instrument of research and a platform for personal teaching
  5. 5. THE EXHIBITION AREA i.The Exhibition area of the Medical Museum is divided into various sections.The main sections are:  a. History of Medicine Section  b. NormalAnatomy Section  c. Morbid (pathological) Anatomy Section  d. Histology Section  e. Haematopathology Section  f. Radiology and Osteology Section  g. Microbiology and Parasitology Section  h. Interactive Corners
  6. 6. DIVISION / PARTS OF MUSEUM EVOLUTION OF PATHOLOGY-  Depicts history of pathology  Dealt by displaying portraits of well known pathologists
  7. 7. SYSTEM ORIENTED DISPLAY  Specimens arranged in divisions on steel racks in a systematic way  It should have a code number  Various aspects of a disease displayed at one place
  8. 8. RECENT SPECIMEN DISPLAY  Fresh specimens displayed after grossing but before histopathological examination  Placed at the entrance of museum with all available information about the patient  Learner can personally handle and feel the specimen
  9. 9. FLUID SPECIMEN  Urine samples, CSF, blood samples etc. in various diseases also preserved
  10. 10. PLASTINATED SPECIMEN  Invented by G. von Hagens  Specimen produced are dry, odourless, near normal in colour and can be kept outside with no bad effects of atmosphere
  11. 11. MUSEUM ON CURRENT TOPICS  A section of museum should be developed to display current topics- AIDS, family planning etc
  12. 12. PANEL OF SIMILIES  Diseased organs compared with familiar objects
  14. 14. BASIC MUSEUM TECHNIQUES Any specimens for museum are handled by following steps:  1. Reception  2. Preparation  3. Fixation  4. Restoration  5. Preservation  6. Presentation
  15. 15.  Reception of the Specimen  Any specimen received in the museum should be recorded in a Reception bookand given a number followed by year (e.g. 32/2013).  This number will stay with specimen even after it is catalogued in its respective place. written on tie-on type label in indelible ink and is firmly attached or stitched to the specimen.  The reception book should contain all necessary information about the specimen (clinical, gross and microscopic findings).
  16. 16.  Preparation of the specimen  An ideal specimen is received fresh in unfixed state. However, it is mostly obtained from pathology laboratory after being examined, thus will already be formalin fixed.  If planning to use a specimen for museum, part of it can be kept without disturbing for museum, e.g. in kidney it can be bisected and one half kept aside for museum.
  17. 17. PREPARATION OF SPECIMEN  Specimen can be obtained from:  Autopsy  Directly from operation theatre  CUTTING OF SPECIMEN:  brain knife  butcher’s knife
  18. 18. FIXATION OF SPECIMEN  Once tissues are removed from the body, they undergo a process of self -destruction or autolysis which is initiated soon after cell death by the action of intracellular enzymes causing the breakdown of protein and eventual liquefaction of the cell.  The objective of fixation is to preserve cells and tissue constituents in as close a life-like state as possible and to allow them to undergo further preparative procedures without change.  Fixation arrests autolysis and bacterial decomposition and stabilizes the cellular and tissue constituents.
  19. 19.  Prior to mounting, specimens should be trimmed according to specifications and fixed in fixatives to avoid decomposition or distortion.  The volume of the fixative should be 10 times the volume of thespecimen.  Insufficient amount of fixative used results in cloudiness of the solution. The colour of the specimens would not be the same and varies from its natural colour. iii. Specimens should be suspended in the fixative and avoid contacting with the Perspex container.This is to ensure good condition of the specimen.
  20. 20.  Penetration rate of the fixative into some organs such as liver, kidney,and spleen are very slow.  This can be overcome by direct injection of fixative.  Basically, 10% formalin is used. However, modified solution contains some additives to improve specimens displayed. Examples of some of the methods are Romhanyi’s Method,Wenthworth’s Method, and Kaiserling’s Method.  Most fixatives used today in museums are based on a formalin fixation technique derived by Kaiserling (1897)..
  21. 21.  Kaiserling recommended that the initial fixation be a neutral formalin (KI) solution and then transferred to a final preserving glycerin solution (KIII) for long term display.  Colour preservation is also maintained with these solutions  Fixation of specimen:  The specimen needs to be kept in a large enough container which can accommodate specimen along with 3-4 times volume of fixative.  Specimen is stored in the Kaiserling I Solution for 1 month depending on the size of the specimen.
  22. 22.  The specimen should not rest on bottom or an artificial flat surface will be produced on hardening due to fixation.  Kaiserling I Solution:  Formalin 1L  Potassium acetate 45 g.  Potassium nitrate 25 g.  Distilled water Make up to 10 litres  Restoration of specimen  It is required to restore the specimens, as they lose their natural color on fixation.  The recommended method is the Kaiserling II method.
  23. 23.  It involves removing the specimen, washing it in running water and transferring to 95% alcohol for 10 minutes to 1hour depending on the size of specimen.  The specimen is then kept and observed for color change for around 1- 1.5 hrs.After this step, specimen is ready for preservation.
  24. 24.  Kaiserling II Solution:  Alcohol 95%  *Store specimen in this solution for 10 minutes to 1 hour depending on size of specimen.  Rejuvenator Solution:  Pyridine 100 ml  Sodium hydrosulphite 100 gm  Distilled water 4 litres  *Formalin decreases the natural colour of the specimen. However, rejuvenator solution restores the colour.
  25. 25.  Preservation of specimen  The recommended solution for this step is Kaiserling III.This is the final solution in which the specimen will remain for display. It is based on glycerine solution.  Kaiserling III Solution:  Potassium acetate 1416 g.  Glycerine 4 litres  Distilled water Make up to 10 litres  Thymol crystals added to prevent moulds.  *Leave solution to stand for 2 – 3 days before using to ensure proper mixing of chemicals.
  26. 26.  Add 1% pyridine as stabilizer.This solution acts as permanent fixative.  Presentation of the Specimen  Initially all museum specimens were mounted in cylindrical jars and sealed with sheep bladder walls.  Later they were replaced by rectangular glass jars.  They were better than cylindrical ones as the flat surfaces afforded a clear view of specimens without any distortion.  They are covered by rectangular glass plates.
  27. 27.  These jars can be purchased readymade or assembled in museum itself, as per need.  Nowadays, Perspex jars are also available, which are lighter than glass jars.  However, they cannot be used to store specimens fixed in alcohol or methyl salicylate as they react with plastics.
  28. 28. FIXATION OF SPECIMEN  Inject with fixative wherever possible  Never wash specimens containing much blood before or after fixing  Keep fresh specimens on thick layer of cotton wool covered with lint  Fix specimens with all its attached structures  Cystic cavities if unopened are inflated with fixative, if opened packed with cotton wool and soaked in fixative
  29. 29. MOUNTING OF SPECIMEN  Re cut /trim irregularities during fixation  Fill with arsenious acid gelatin if the cavities collapse after removal of cotton wool  Cover friable specimen with a layer of arsenious acid gelatin  Soak bile stained specimen in saturated sol. of calcium chloride for 24 hours
  30. 30. MUSEUM JARS AND BOXES  Perspex boxes- lab made/commercial  Glass jars / boxes
  31. 31. ATTACHING SPECIMEN TO CENTRE PLATE  Centre plate thoroughly washed and dried on a fluff less cloth  Place specimen in proper anatomical position  Stitch specimen to centre plate with nylon/linen thread  Centre plate with specimen is next fixed in box
  32. 32. FILLING AND SEALING OF BOXES / JARS  Boxes filled with mounting fluid+0.4%sodium hydrosulphite  Fill 1 cm above the specimen height  Remove any air bubbles present  Seal top of the box with Perspex cement  Seal glass jars with asphaltum rubber compound
  33. 33. STORAGE OF SPECIMEN  Easy and certain identification  Separate container for each specimen  Appropriately labeled  Accompanied with reference book
  35. 35. SPECIAL METHODS  MACERATED SPECIMEN OF BONES (osteosarcoma,osteoma,chronic osteomylitis,tuberculosis)  Cut surface should be clean and even  Excess soft tissue trimmed off  Boiled in tap water or N/10 sodium hydroxide solution, degreased by immersing in chloroform 3-4 hours ,dried in incubator,bleached in hydrogen peroxide  Mounted dry on a centre plate or with perspex support
  38. 38. SPECIAL METHODS- CALCULI  Preserved- Dry mounting - mounting in gelatin with added formalin  Technique –cut stone in two halves - polish cut surface with sand paper - assemble in appropriate group  Mount on centre plate and file until the stone fits tightly when pressed halfway through the jar.
  41. 41. TRANSPARENT SPECIMEN (EG:BONES OF EMBRYOS,CIRCULATORY SYSTEM) Dawson’s technique:  Specimen fixed in 95% alcohol  Soft tissues cleared in potassium hydroxide  Extract fat by treatment in acetone  Bones stained in alizarin red S solution  Tissues passed through increasing concentration of glycerine  Finally mounted in pure glycerine
  43. 43. GOUGH AND WENTWORTH PAPER MOUNTED SECTIONS  Thin sections of entire organs are mounted on paper  Large number of such sections are stored in the form of a book  Examined as transperencies  Organ most commonly treated- Lung  Others- liver, kidney, heart
  44. 44. PLASTINATION  A technique to preserve whole bodies or body parts  Water and fat are replaced by certain plastics  Specimens can be touched, do not smell or decay  Retain most properties of original sample
  47. 47. CONCEPT OF PLASTINATION- FORCED IMPREGNATION Fixation- body embalmed in formaldehyde to halt decomposition Dehydration in acetone- water in tissues replaced by acetone Forced impregnation in vacuum- specimen placed in a bath of liquid polymer such as silicon rubber, polyester or epoxy resin Acetone boils, vaporizes, leaves the cell being filled with liquid plastic
  48. 48. Hardening- By treating the plastic with gas, heat and UV light
  49. 49. USES  Models and teaching tools  Fewer animals have to be killed for research  Preservation of more flexible, durable and life like specimens
  50. 50.  Catalogues  It is essential that a plan of the museum should be visible to the visitor on  entering; each section should be clearly labelled.  Several duplicates of each catalogue should be available.
  51. 51. SUMMARYSUMMARY  All the medical councils of various countries have made it a compulsion to develop pathology museum in medical education  Serves as a personal teaching tool  Plastinated models can be used to demonstrate various surgical procedures  Historical value
  52. 52. REFERENCES  Journal Royal Society of Medicine  Cellular pathology by Culling  Nagalotimath S.J. pathology museum Department of Pathology & Microbiology J.N. Medical College, Belgaum  Journal.Pathol.Bacteriol  Internet