PERIPHERAL VASCULAR DISEASES 



I2 33 



livedo reticularis (primary livedo reticularis), and 

 3) symptomatic livedo reticularis (secondary livedo 

 reticularis). 



Cutis marmorata refers to a state characterized 

 by transient reticular discoloration producing a 

 marble (hence the term "marmorata") pattern to 

 the skin which appears on exposure to cold but, un- 

 like the other types of livedo, it is not permanent and 

 disappears with warmth. It is considered that in this 

 state there is no organic pathologic alteration in the 

 peripheral circulation but rather that the disturb- 

 ance is a vasomotor phenomenon. It has been noted 

 to be frequent in infants and young girls and may 

 disappear as they grow older. 



In idiopathic livedo reticularis (primary livedo 

 reticularis) the reticular discoloration is relatively 

 permanent and persists to some degree regardless 

 of temperature changes. As noted before, however, 

 the degree of discoloration is accentuated by exposure 

 to cold. There may be minimal to no organic changes 

 in the vessels except increased number and dilatation 

 of capillaries in the livid areas. Feldaker et al. (23) 

 also noted in these areas varying degrees of endar- 

 teritis and endophlebitis of the smaller vessels. At 

 times there is occlusion, periarteritis and periphlebitis 

 and occasionally, thickening of the walls of arterioles 

 in the dermis and subcutaneous tissue. 



Symptomatic livedo reticularis (secondary livedo 

 reticularis) is the form of the disorder associated 

 with or secondary to other dermal, vascular, or 

 systemic diseases. These have been outlined in the 

 accompanying classification of peripheral vascular 

 diseases (see Appendix to this chapter). 



The large arteries such as the dorsalis pedis, pos- 

 terior tibial, and popliteal are not involved by occlu- 

 sive disease and likewise venous insufficiency is not a 

 factor in livedo reticularis. Digital blood flow after 

 interruption of sympathetic nerve supply is usually 

 normal (60). Feldaker el al. (23) have recently 

 summarized the probable pathophysiology of this 

 disease. The perpendicular arterioles, supplying the 

 skin from below, and the central zone capillary 

 arborizations have a slightly greater tone and faster 

 linear rate of blood flow than the peripheral capil- 

 laries. Either because of organic change (as described 

 earlier) or vasospasm of arteries and arterioles of the 

 skin or both, capillary atony and slowing of blood in 

 peripheral capillaries are further increased, resulting 

 in a livedo reticularis pattern in annular rings about 

 central paler areas. Cold causes an increased vaso- 

 constriction of the arteries and arterioles, resulting 

 in an intensification of the livedo. When the periph- 



eral capillaries are only temporarily atonic and di- 

 lated, and the arteriolar supply is only temporarily 

 reduced, the transient cutis marmorata results; 

 but if the changes are more or less permanent, then 

 true livedo reticularis is produced. On elevation of 

 the affected parts, the livedo decreases if the venules 

 draining the areas are patent and can drain the 

 stagnant blood from the capillaries. Warmth and 

 sympathectomy reduce the spasm of the arteries 

 and arterioles and thus reduce the degree of dis- 

 coloration. 



These observations and interpretations are at- 

 tractive. As in Raynaud's disease and acrocyanosis, 

 however, the basic factors underlying the vascular 

 disturbances and manifestations are unknown. 

 Whether or not the defect is primarily one of local 

 vessel fault or one of sympathetic nerve disturbance, 

 and whether or not localization of the disorder to 

 these sites is determined by congenital or acquired 

 mechanisms, are not known. Relief of livedo reticu- 

 laris and return to normal color has been reported 

 following sympathectomy and also following the 

 administration of acetyl-beta-methylcholine (22). 

 The problems surrounding supposition of a sympa- 

 thetic nerve disease as the basic disturbance are 

 essentially as discussed for Raynaud's disease and 

 acrocyanosis. 



CAUSALGIA AND RELATED SYNDROMES. This is one of 



the most confused areas of all in peripheral vascular 

 disease today. Definitions are poor; criteria for classi- 

 fication and diagnosis, variable; and terminology, 

 diffuse. The unifying characteristic of this group is 

 the development of a bizarre symptom complex 

 following some type of injury to an extremity. This 

 posttraumatic syndrome consists in general of pain, 

 paresthesia, trophic changes, edema, and evidence 

 of autonomic nervous system dysfunction. In this 

 group of diseases are included major causalgia, 

 minor causalgia, traumatic vasospasm, acute atrophy 

 of bone, Sudeck's atrophy, reflex nervous dystrophy, 

 traumatic angiospasm, posttraumatic painful osteo- 

 porosis, neurovasospastic phenomenon, chronic post- 

 traumatic edema, posttraumatic reflex dystrophy, 

 sympathetic dystrophy, neurovascular reflex dys- 

 trophy, atypical causalgia, posttraumatic spreading 

 neuralgia, reflex nervous atrophy, irritative nerve 

 lesions, sympathalgia, posttraumatic pain syndrome, 

 peripheral acute trophoneurosis, postamputation 

 syndrome, and traumatic neuralgia. All these terms 

 have been employed in reports in the literature, and 

 undoubtedly others have been used. Each term has 



