Venous Leak

Atherosclerotic occlusion or stenosis of the pudendal or cavernosa arteries Arterial damage from pelvic radiation Venous leak... 

In the field of erectile dysfunction, penile vascular imaging modalities have diminished in importance over the past 10 years with the introduction of new effective oral medications and recognition that surgical treatment of both penile venous leak and arterial insufficiency has poor long-term clinical outcomes. 

Vale JA, Feneley MR, Lees WR, Kirby RS (1995) Venous leak surgery long-term follow-up of patients undergoing excision and ligation of the deep dorsal vein of the penis. Br J Urol 76 192-195... 

In general, the plaques are found peripherally, usually on the dorsal aspect of the penis. However, the abnormal tissue may extend beyond the palpable lesion (Iacono et al. 1993 Somers and Dawson 1997), or even into the corporal tissue or intercaver-nosal septum (Brant et al. 2007). An area of relative inelasticity and contracture results in both loss of length and ipsilateral deviation, as the normally elastic fibers are replaced by relatively noncom-pliant collagen-rich tissue. The inelasticity of the plaques may also impede the normal vasoocclusive mechanism of erection and thus leads to venous leak (Hellstrom and Bivalacqua 2000). 

Fig. 18.8. Posttraumatic penile deformation following untreated penile fracture. Color Doppler US shows venous leak at the level of the scar due to incomplete distension of the erectile tissue...

It has been reported that cement leakage is more common when PV is used for metastatic osteolytic tumors or myelomas of the spine than in osteoporotic fractures. However, Vasconcelos et al. (2002) observed no major differences, although they noted venous leaks slightly more frequently in patients with metastatic lesions. When PV was performed in osteoporotic vertebral compression fractures, leakage into the disc space was more commonly observed. Mousavi et al. (2003) reviewed post-procedural GT scans in patients with osteoporotic vertebral compression fractures and metastatic lesions of the spine and concluded that in osteoporotic vertebrae leakage occurred mainly into the disc, whereas in metastatic lesions it was found in various different locations. 

Lymphatic vessels infiltrate tissues that are bathed in fluid released from blood into those tissues. Pockets of fluid collect in the tissues, and increased pressure allows the fluid to seep into the lymphatic vessels. Whereas blood vessels return deoxygenated blood to the heart to be pumped to the lungg for oxygen, lymphatic vessels return fluid that has leaked out of the capillaries into various tissues. However, before this lymphatic fluid is rejoined with venous fluid at the thoracic duct, it is filtered through the lymph nodes to remove infectious agents. 

The fibroblasts and other cells of the stroma are surrounded by a dense layer of secreted materials through which nutrients must reach the cells and waste must be excreted. The arteriolar ends of blood capillaries have tiny junctions between the endothelial cells so that small molecules leak out under hydrostatic pressure. This fluid, interstitial fluid, feeds the stroma and then drains back into the venous end of capillaries under the influence of increased capillary osmotic pressure and reduced hydrostatic pressure. It contains glucose, amino acids, some metabolites such as citrate, pyrophosphate, and extracellular ATP (Sect. 9.1.4) as well as vitamins and inorganic ions. It is free of the proteins and other large molecules present in blood plasma, but it receives soluble proteins that are secreted into it by matrix cells such as fibroblasts. 

It is well-known that fluid tends to leak from the arterial and to be reabsorbed at the venous end of capillaries (Staub, 1974). Fluid not absorbed at the venous end of the capillaries is drained from the tissue spaces by the lymphatic system and returned to the vascular system via the lymphatic trunks which join the venous system at the root of the neck. Oedema is the accumulation of excess fluid in the tissues and may be produced by a number of causes. These include ... 

Medical and nursing staff dealing with central venous catheters (CVC) should be aware of specific risk factors and safety hazards associated with this access type (damage of the vessels and/or surrounding tissue at CVC insertion, fibrin sheath formation, leak of the anticoagulation lock solution into the vascular system, etc.). 

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