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Technique for reconstituting fixed cadaveric tissue.

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Technique for Reconstituting Fixed
Cadaveric Tissue
SEAN P.A. BLANEY
AND
BARRY JOHNSON
Department of Anatomy and Developmental Biology, University College London, London
W C lE 6BT, England
ABSTRACT
Dissecting room cadavers used over a prolonged period inevitably
become desiccated, especially in well-ventilated surroundings. It is particularly
desirable that dissections used for end-of-year examinations be restored to their
original condition. We describe here a quick and simple procedure designed to
restore neglected specimens to their former condition at dissection. Specimens
were either soaked for 24 hr in a standard solution of fabric conditioner or sprayed
with the same standard solution. The specimens were then wrapped with muslin
soaked in the conditioner and covered with polythene sheeting for 1 week. The
results obtained were excellent and much superior to a short soak in water. The
results further indicate that this technique may have other applications in the
preparation of fixed histological material.
Embalmed cadavers, or parts of cadavers, easily
mummify without constant care and attention in the
air-conditioned dissecting room. Tompsett (1970) has
suggested that frequent applications of a mixture of
glycerin and phenol together with the covering of dissected parts with muslin stockinette soaked in the wetting fluid helps to stave off desiccation. Occasionally,
however, when the cadavers are under the care of new
or inexperienced students, some tissues (especially
those dissected earlier in the year) may deteriorate. We
have had considerable success in reconditioning such
neglected tissues using a commercially available fabric
conditioner. This has proved especially useful prior to
the use of specimens in oral or practical examinations
held at the end of the academic year.
Turner and Holtom (1981) first advocated the use of
fabric conditioner on preserved human tissues. They
found that in the reconstitution of Egyptian mummified tissues, prior to paraffin wax sectioning, the fabric
conditioner Comfort1 had many advantages over the
more “classical” rehydrating agents such as Ruffer’s
(1921) or Sandison’s (1955) solutions.
MATERIALS AND METHODS
The fabric conditioner used in this study was Concentrated Comfort. Concentrated Comfort contains lanolin in conjunction with a quarternary ammonium salt.
Detailed information concerning the preservatives and
colorants contained in Concentrated Comfort has not,
however, been made available by the manufacturer.
The solution constituted approximately 30 ml of Concentrated Comfort diluted in 5 litres of tapwater.
Each treated cadaver had originally been embalmed
under pressure, using a peristaltic pump, with approximately 20 liters of preservation fluid (Table 1). The
cadavers had been used in the process of dissection by
Comfort and Concentrated Comfort are produced by Lever Brothers
Limited, Lever House, Kingston-upon-Thames, UK.
0 1989 ALAN R. LISS, INC.
medical and dental students for 8 months prior to reconstitution with the fabric conditioner.
Method
The softener was used on 23 cadavers in the dissecting room. Firstly, an atomiser was used on 22 cadavers
to apply solution to badly desiccated superficial regions. The treated regions were then wrapped with
muslin cloth which had been soaked in the diluted conditioner. Finally, polythene sheeting was placed over
the cadavers.
One further whole dissected cadaver, together with a
group of isolated organs and limbs, was immersed in a
bath of conditioner solution for 24 hr and then wrapped
in conditioner-soaked muslin and covered with a polythene sheet.
All the above specimens were examined daily for 1
week.
RESULTS
In all cases the conditioner softened and moistened
the tissues. In addition the tissues reassumed a paler,
more natural, coloration. This may, however, have
been caused by various coloring agents in the fabric
softener.
For the first 22 cadavers, one spray application and a
week of wrapping proved sufficient to reconstitute superficial dehydrated tissues. Stored limbs and organs
such as the heart, lungs, and liver benefited greatly
from a 24-hr total immersion and a week of wrapping.
In some cases, anatomical structures difficult to identify a t initial dissection became more clearly contrasted after soaking the specimens. Total immersion
Received June 6, 1988; accepted September 14,1988.
Address reprint requests to S.P.A. Blaney, Department of Anatomy
and Developmental Biology, University College London, Gower
Street, London WClE 6BT, England.
TECHNIQUE FOR RECONSTITUTING FIXED CADAVERIC TISSUE
+
Hardened tallow
551
Methyl Group
Fig. 1. Diagram showing the structure of dihardened tallow dimethyl ammonium chloride. (Modified
from Turner and Holtom, 1981.)
TABLE 1. Constituents of the preservative fluid
Formaldehyde solution (39-41%)
Phenol solution (80%)
Methanol (99%)
Teepol detergent'
Tanwater
4 litres
2 litres
2 litres
50 ml
16 litres
'Teepol is produced by Shell UK Limited, Shell-Mex House, Strand,
London, UK.
of the whole dissected cadaver for 24 hr followed by a
week of wrapping also produced excellent results, with
the remaining internal organs in particular (such as
the stomach and pancreas) being more supple.
The reconstituted specimens remained free of tissue
damage and fungal attack for up to 6 months prior t o
removal for burial. The cadavers, however, were still
occasionally treated with the glycerin and phenol wetting fluid throughout this period.
sues can be successfully reconstituted using commercially available fabric conditioners. They reassume a
more pliable texture, a paler coloration, and appear to
be no more prone to drying or fungal attack than untreated tissues. Superficial striated muscle, nerves,
and vessels benefit from a simple spray application
whilst deeper structures require 24-hr immersion.
Human material is valuable and expensive. Large
classes of medical and dental students are now common
in many medical and dental schools, and a close supervision of cadavers is thus often difficult. This inevitably leads t o the deterioration of useful dissections. We
hope that the information presented here will prove of
use to those who might need to recondition partly desiccated human tissue.
ACKNOWLEDGMENTS
The authors wish to thank Professor J . Pegington,
Department of Anatomy and Developmental Biology,
University College London, for use of cadaveric mateDISCUSSION
rial. Thanks are also expressed to Dr. M.C. Dean, DeFabric conditioners are surface-active agents; i.e., partment of Anatomy and Developmental Biology,
they reduce surface tension. The surface-active compo- University College London, and Mr. E. Jouchin, Denent, in most cases, is cationic. The active component partment of Human Anatomy and Cell Biology, Uniin the conditioner used in this study, as Evans (1969) versity of Liverpool, for their suggestions throughout
pointed out, was dihardened tallow dimethyl ammo- the study.
S.P.A. Blaney was in receipt of a Medical Research
nium chloride (Fig. 1.). Other brands of commercially
available fabric softener also have a similar structure Council Research Studentship.
to Concentrated Comfort. While the fabric conditioner
LITERATURE CITED
carries a positive electrical charge in solution, the surEvans,
W.P.
1969
Cationic
fabric softeners. Chem. Ind. (Land.), July,
face of the soft tissues are anionic. The quarternary
ammonium salt particles are thus sequestered from the Lever893-903.
Brothers Limited 1981 Fabric Conditioner Information Sheet,
rinse solution onto the tissue. The particles are of such
LB5. Kingston-upon-Thames.
a size that they pass between the fibres without actu- Ruffer, M.A. 1921 Histological studies on Egyptian mummies. In:
Studies in the Paleopathology of Egypt. Univ. of Chicago Press,
ally penetrating them. Conditioners are adsorbed reChicago, pp. 49-89.
gardless of whether soft or hard water has been used Sandison,
A.T. 1955 The histological examination of mummified ma(Lever Brothers Limited, 1981).
terial. Stain Technol., 30:277-283.
The effect of the conditioner on natural textile fab- Tompsett, D.H. 1970 Anatomical Techniques. E. and S. Livingstone,
London, p. 7.
rics is to both soften and lubricate the fibres. It is preP.J. and D.B. Holtom 1981 The use of a fabric conditioner in
sumed that the conditioner acts on the fixed human Turner
the reconstitution of mummified tissue prior to paraffin wax sectissue in a similar manner.
tioning for light microscopical examination. Stain Technol. 56:1,
35-38.
In conclusion, we suggest that desiccated fixed tis-
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