Museum techniques

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