A SIXPLE METHOD FOR THE PREPARATION O F DVRARLE ANATONICAL SPECIMENS

FRED A. METTLER AND CECILTA C. METTLER Department of Anatomy, University of Georgia School of Mediehe

The utility of a method for the production of undistorted durable (hard and waterproof) specimens in gross anatomy is apparent to any worker in the field. The fact that such speci- mens can be colored, injected and stored in drawers or upon shelves adds to the method's practicability.

TECHXIQTiE

1. Fix specimen in formalin. 2. Wash in water and dehydrate to 95 % alcohol. 3. Transfer to benzyl alcohol (Nerck) until saturated. 4. Place in saturated solution of Bakelite resin XR 6787 dis-

solved in 50 7. benzyl alcohol and 50 "/. glycerin a t 65°C. 5. Place in incubator at 50" to 60°C. until the solution

changes to a mushy white mass of a consistency re- sembling ' Farina. '

6. Remove specimens from mass, rinse off with hot water meanwhile brushing excess solid off with a moderately stiff brush.

7. Allow to dry. If specimen is a gross cross section sand- paper surface smooth and coat specimen with a layer of Bakelite resin XR 7403. Return to oven for 48 hours and a glass-like surface will result.

MODIFICATIONS

If the specimen is of irregular surface, such as a head, this may be used colored or uncolored as it is after step 6. If the arteries, veins and ducts are to be colored this can be

profitably achieved by injecting with starch colored with 499

500 F. A. METTLER AXD C. C. METTLER

permanent pigment (Toch Bros., New York) during step 1 or before. The other structures may be painted with oils during step 7.

For the preparation of casts of the inside of hollow organs or the. preparation of an independent vascular tree Bakelite resin XR7403 may be used. This is colored with acid fast pigments (Toch) and is injected. The injected vessel is placed in the oven for 48 hours and is then rigid and the tissue can be digested off.

The benzyl alcohol of step 3 may be used over and over and the resin mush of step 6 can be redissolved and used over.

With these methods colored or uncolored gross cross sections, dissections corrosion or total specimens such as polydactylous extremities can be prepared with or without previous injection of the vessels and ducts in color. Any of these preparations can be stored without danger in drawers, hung on walls or put on shelves. They are not affected by dampness or warmth and are much more durable than compo- sition models.

We should like to express our appreciation to the Bakelite Corporation and especially Mr. H. L. Bender.