Sven Bellman

Vascular reactions after experimental cold injury; a microangiographic study of rabbit ears.

overlooked, and in fact it is only recently that it has been realized that secondary factors, especially impaired blood circulation, may also play an important role in the development of tissue necrosis (1, 2). In the case of cold injuries the situation has been different, for in this type of injury it has long been appreciated that the damage in the tissue is due not only to the initial thermal injury to the cell but also, and to a considerable extent, to secondary factors which can be influenced by subsequent treatment. Thus the idea that rapid warming of a local

Transformation of the Vascular System in Cold-Injured Tissue of the Rabbit's Ear

The vascular reactions associated with cold injuries have been widely studied since Cohnheim’s fundamental work’ on this subject about 80 years ago. Most of these studies have been devoted to the early reactions occurring within the first few minutes or hours after the cold trauma; for general reference on this subject, see the &dquo;Transactions of the First Conference of Cold Injury.&dquo;2 In an earlier investigation reported from our laboratory3 somewhat later, vascular reactions after local cold trauma were studied in the

I. Microradiography: A Review*

Various types of microradiography are treated in this survey. The resolution possible is about 0·5 μ in ideal cases. Quantitative microradiography with monochromatic X rays permits certain histo-chemical elementary analysis. Utilising very soft X rays it is possible to determine the dry weight of cellular structures. The applications of microradiography to the study of the degree of mineralisation in calcified tissues is discussed in detail. The use of microangiography in demonstrating the finest blood vessels, microangiography, as well as a short survey of X-ray microdiffraction techniques are discussed.

Adaptations of collateral arterial pathways. An in vivo microangiographic study in the rabbit's ear.

that the vascular changes developed in consequence of altered pressure gradients and flow patterns produced by the ligatures. In the current work we (1) measured the pressure fall-off in the two asymmetric limbs of the above system, (2) altered pressure gradients -till further by an additional ligature, and observed the subsequent vascular changes, and, 13) compared these vascular responses with those following intraluminal obstruction of an equivalent arcade. 1. By direct cannulation of the arterial system at the three relevant points and recording pres-

The Viability of Experimental Aortic Grafts, and its Influence on the Functional Result of Transplantation

the blood flow, and much experimental work has been carried out to determine the conditions which influence the effectiveness of the transplantation. In particular, the question of whether living blood vessel segments give better functional results than dead ones has attracted great attention, but there is still no final agreement although many investigators have studied this problem. In earlier studies, the methods used to demonstrate the presence of life in the blood vessel transplants usually involved either histologic examination after fixation of the material, determination of the tissue respiration, or tissue culture experiments. In studying the viability of vascular transplants their vascularization has also been studied.

Stereo-micro-lymphangiography

The theoretical basis of stereoscopic micro-lymphangiography and its practical serviceability is discussed. Stereoscopic methods in micro-lymphangiography afford better information on the form and configuration of lymphatics than does the two-dimensional procedure. Photogrammetric calculations on the basis of measurements made on stereo-micro-lymphangiographs enable the positions of different structures to be determined in depth.

On the extracorporeal survival of aortic segments; isotope and respiration studies.

1 From Chemistry Department II and the Department for Physical Cell Research, Karolinska Institutet, and the Department of Surgery, Sabbatsbergs Sjukhus, Stockholm. The technique of vascular surgery has developed rapidly in the past decade, and there has been a greatly increased need of suitable materials for the repair of vascular defects resulting from cardiovascular disease, operations for malignant growths, and inj uries. Initially, it seemed advisable to use autogenous vascular segments for this purpose, but in many cases it proved exceptionally difficult to obtain segments of appropriate size and shape, especially for grafting to the largest blood vessels. For this reason, homologous grafts came into widespread use. In the last few years synthetic materials as well, chiefly various types of plastics, have been tried experimentally and have been used clinically to some extent. At present, homologous arterial segments preserved in different ways constitute by far the most widely used material for arterial grafting. Numerous investigators (1-13) have worked on the problem of the viability of arterial grafts. A question that has received considerable attention is whether