A Modified Lead Oxide Cadaveric Injection Technique for Embalmed Contrast Radiography

Sir: In the past four decades, plastic surgery has enjoyed an anatomical renaissance in which old techniques have been revived and refined and new procedures evolved. The two most detailed studies of the cutaneous circulation were performed by Manchot in 18991 and Salmon in 1936.2 In 1986, Rees and Taylor developed an improved protocol.3 There have been many attempts to use the Rees-Taylor technique on embalmed cadaveric tissue but, until recently, without success.4 Four upper limbs were harvested. The cadavers had been treated with Genelyn Solution (Anatomical Series nonflammable S6; Genelyn Pty. Ltd., South Australia, Australia) and stored in vacuum plastic bags in the cool room (4°C) for up to 1 year. A suitable sized cannula was inserted directly into the subclavian or axillary vessels at the disarticulated level. Heavy silk or linen was used to tie the cannulae in place. Then, 50 ml of 6% hydrogen peroxide (Orion Laboratories Pty. Ltd., Western Australia, Australia) was injected. The cannula was closed using surgical forceps to leave the solution in the vessels for up to 3 hours. Leaks were checked and secured on the cut surfaces. During this time, the lead oxide mixture was prepared: 36 g of milk powder (Nuture, Toddlers; Heinz Ltd., Victoria, Australia) and 200 g of lead oxide (P3O4 Red lead; Ajax Chemicals, Australia) mixed with 40 ml of tap water and ground into a fine, smooth paste with a pestle and mortar. Finally, 80 ml of boiling water was added to the paste and stirred thoroughly. A 50-cc syringe with 35 to 55 ml of mixture was injected in a pulsatile fashion and stopped when greatest resistance occurred. The limbs were stored in the cool room. The mixture solidified in the small vessels after 24 hours and in large vessels (brachial artery) after up to 10 days. Whole limbs were radiographed at a distance of 150 cm between digital cassette (Fuji FCR IP CC; Fiji Film Corp., Tokyo, Japan) and x-ray source (Linear x-ray Collimator MC 200C; Progeny, Inc., Buffalo Grove, Ill.). We used 100 kV, 0.32 second, and 85 mA for the shoulder; 75 mA for the upper arm; and 65 mA for the forearm (Fig. 1).Fig. 1.: Inverted radiograph of a right upper arm (embalmed) injected with lead oxide mixture showing the details of the vascular anatomy.The integument and muscle were removed and radiographed (55 mA, 100 kV, 0.32 second; and 60 mA, 100 kV, 0.32 second, respectively) (Fig. 2).Fig. 2.: Inverted radiograph showing the details of the blood supply of the deltoid.This study was successful because (1) the cadavers had been embalmed using the Genelyn solution, leaving the tissue more pliable; (2) hydrogen peroxide was used before the lead oxide injection; and (3) the lead oxide injectant had been modified.5 It is thought that we can apply more pressure during injection, as the vessel walls in embalmed cadavers are tougher than in fresh cadavers. There were no vessel ruptures in our four upper arm injections. Smaller syringes (5 or 10 ml) contribute to higher pressure. With limited access to fresh cadaveric tissue, this technique broadens the application of cadaveric radiography to unembalmed tissue. We have reported an embalmed cadaveric injection using a modified lead oxide mixture. It provides results equal to those obtained from the unembalmed (fresh) cadaveric injection. ACKNOWLEDGMENTS The authors thank Prue Dodwell, G. Ian Taylor, Chris Briggs, Susan Kerby, and Lauren Richardson for invaluable support. Wei-Ren Pan, M.D. Nicholas M. Cheng Fatima Vally The Jack Brockhoff Reconstructive Plastic Surgery Research Unit Department of Anatomy and Cell Biology University of Melbourne Parkville, Victoria, Australia