Topical modes in the preparation of human spleen specimens for routine scanning electron microscopy studies

Various preparatory techniques were used to improve scanning electron microscopy images of the fine structure of vascular, cellular, and cordalreticular components of normal human spleens. The progressive method of fixation (GTGO) applied in the present study, allowed air drying of the tissues and rendered the specimens conductive even in newly fractured surfaces. Vascular perfusion proved necessary only in studies of the splenic blood vessels, while a simple immersion of tissue blocks in the washing solution resulted in better images of the white pulps. Interstitial (transsplenic) perfusion was found to be superior to vascular perfusion for routine preparation of spleen tissues, and freeze-cracking did not necessarily lead to improved images of the specimen's surfaces. Combined with proper washing and shaping protocols, the GTGO procedure is shown to be a superior mode of specimen preparation, abolishing most traditional artifacts and obtaining clear images of the complex splenic tissue.