museum techniques
TRANSCRIPT
MUSEUM TECHNIQUES
MUSEUM A place to exhibit objects
An instrument of research and a platform for personal teaching
PATHOLOGY MUSEUM, SUBHARTI MED. COLLEGE
BLACKBURN BUILDING, UNIVERSITY OF SYDNEY AUSTRALIA
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. Normal Anatomy 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
DIVISION / PARTS OF MUSEUM EVOLUTION OF PATHOLOGY- Depicts history of pathology Dealt by displaying portraits of well
known pathologists
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
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
FLUID SPECIMEN Urine samples, CSF, blood samples etc. in various
diseases also preserved
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
MUSEUM ON CURRENT TOPICS A section of museum should be developed to display
current topics- AIDS, family planning etc
PANEL OF SIMILIES Diseased organs compared with familiar
objects
CONFERENCE ROOM
BASIC MUSEUM TECHNIQUES
Any specimens for museum are handled by following steps:
1. Reception 2. Preparation 3. Fixation 4. Restoration 5. Preservation 6. Presentation
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).
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.
PREPARATION OF SPECIMEN
Specimen can be obtained from: Autopsy Directly from operation theatre
CUTTING OF SPECIMEN: brain knife butcher’s knife
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.
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.
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)..
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.
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.
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.
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.
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.
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.
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.
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
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
MUSEUM JARS AND BOXES Perspex boxes- lab made/commercial
Glass jars / boxes
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
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
STORAGE OF SPECIMEN
Easy and certain identification
Separate container for each specimen
Appropriately labeled
Accompanied with reference book
COMPUTERIZED UPGRADE CATALOGUED TEACHING SPECIMENS. STORED ON CD-ROM DISKS.
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
MACERATED SPECIMEN OSTEOGENIC SARCOMA MOUNTED ON CENTRE PLATE IN PERSPEX BOX
USE OF PERSPEX SUPPORT –NORMAL MANDIBLE IN CENTRE
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.
OXALATE CALCULI WITH PIGMENTATION
CALCULI OF SIMILAR TYPE MOUNTED TOGETHER
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
MOUSE EMBRYO TREATED BY DAWSON’S TECHNIQUE
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
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
DEMOSTRATION OF BRONCHIAL TREE BY PLASTICS
PLASTINATION OF ABNORMAL FETUSES
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
Hardening- By treating the plastic with gas, heat and UV light
USES Models and teaching tools
Fewer animals have to be killed for research
Preservation of more flexible, durable and life like specimens
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.
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
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
