Examining the microanatomy of various fetal body parts using the orcein-picroindigocarmine staining method.

It is difficult to distinguish muscle, vessel, nerve, fascia, tendon and many other structures in fetal sections. The aim of the study reported here was to research the practicability of orcein-picroindigocarmine staining for distinguishing anatomic structures in histological sections containing complex structures. Histological serial sections of hand, foot, head and neck of four 18- to 20-week old fetuses were used. Bone matrix was stained bright blue, collagen fibers tones of green to blue, elastic fibers brown, cartilage matrix tones of pink, and chondroblasts blue. Muscles and erythrocytes were stained yellow to green, epidermis reddish brown, skin appendices including hair and nail stained light yellow to green.