PUBLISHED reports of the use of fibrin as a substitute for sutures aroused my interest in the possibility that this material might be used in corneal grafting. The use of plasma proteins in surgery has been greatly expanded under the impetus of the recent war, particularly since the Harvard Physical Chemical Laboratories had been commissioned to study the fractionation of human blood plasma. A great many uses have been developed from the fibrinogen fraction, which is the biologic plastic cement substance of the blood.
Fibrinogen molecules are long and narrow and become oriented in parallel in a fast flowing stream.1 When a clot is formed, these molecules form a meshwork pattern. The mechanism of clotting is believed to be brought about by the action of thrombin on fibrinogen.2 Thrombin exists in the blood plasma as prothrombin and is transformed into thrombin in the presence of calcium ions