Microsurgical techniques using human placenta.

Dr. Flavio Ramalho Romero – Praca Amadeu Amaral 27 / 5o andar 01327-010 Sao Paulo SP Brasil. E-mail: romerocnr@gmail.com / icne@icne.com.br Training in microsurgical techniques is the first step to allow procedures in the central nervous system. One of them is the dissection of human placenta. Others include mannequin head, virtual reality environment, animal and cadaver dissections. The human placenta is a maternalfetal structure constituted of a bigger fetal portion and a smaller maternal portion. The fetal membranes and the placenta are responsible for protection, nutrition, breath, excretion and hormone production. The placenta usually shows an ovoid shape with a 16–20 cm diameter and a 2–3 cm thickness. It weighs between 500 and 600 gr. The umbilical cord is usually composed of a vein and two arteries. The fetal surface has a fetal corion – amniotic membrane which is very similar to the cerebral arachnoid and a rich vascular component with 1–6 mm diameter vessels. The anterior cerebral artery has 1–3 mm diameter and the medium cerebral artery one is between 2.4 and 4.6 mm. On the other hand, the vertebral artery has 0.92–4.09 mm diameter, the posterior cerebral and the lower posterior cerebelar arteries ones are between 0.65 and 1.78 mm. Therefore, the human placenta is an excellent material for microsurgical technique training.