Variations and abnormalities of veins

Anomaly and topography of veins are more variable than arteries.

The upper vena cava as a rare non-permanent influx can have the right upper pulmonary vein, the right internal thoracic vein, the right upper intercostal vein. Rarely there is a paired (right and left) upper hollow vein, while the upper hollow vein is formed from the left brachiocephalic and semi-unpaired veins. Sometimes left a common common venous (cuvier) duct connecting the left brachiocephalic vein with the coronary sinus of the heart. In some cases, there is a communication between the influxes of the superior hollow and pulmonary veins.

Unpaired and semi-unpaired veins are variable in caliber, topography, and abundance of tributaries. Sometimes a semi-unpaired vein empties into an unpaired vein with 2-3 trunks. The level of confluence of the semi-unpaired vein into the unpaired is variable: in 20% of cases it falls at the level of the VI thoracic vertebra, in 6% - in the VII thoracic, in 14% in the VIII thoracic vertebra, in other cases at the level of the IX-XI thoracic vertebrae. An additional semi-unpaired vein is sometimes absent.

Inflows of the internal jugular vein are sometimes the upper thyroid vein and some inflows of the lingual vein. Diplomatic and emissary veins in elderly and elderly people in places disappear. Inflows of the facial vein are often weakly expressed. Inflows of the external jugular vein are unstable, there may be no anterior influx-anastomosis with the submandibular vein (posterior inflow). The external jugular vein can form at the posterior margin of the sternocleidomastoid muscle. Sometimes, the internal jugular vein inflows of the facial vein, lingual veins, an additional internal jugular vein, the vein of the breast, located subcutaneously. There is an unpaired middle vein of the neck, which passes subcutaneously in front of the trachea. The anterior jugular veins are very variable in number and topography.

The subclavian vein sometimes passes together with the subclavian artery in the interstitial space. The inconstant inflow of the subclavian vein is the superficial vertical (longitudinal) vein of the neck and the right upper intercostal vein. Rarely subclavian vein is double.

The brachiocephalic veins are variable in the number and direction of their tributaries. Sometimes an axillary vein enters the brachiocephalic vein. Occasionally, the subclavian and internal jugular veins are opened separately into the brachiocephalic vein. Rarely the brachiocephalic vein forms local expansions alternating with its narrow sections.

Occasionally there are two axillary veins - medial and lateral, going in parallel, sometimes connecting with each other by anastomoses. The number of brachial veins can range from one to four. The prominence of their topography is very variable.

Lateral saphenous vein of the hand may be absent, sometimes doubled. The medial subcutaneous vein of the arm sometimes goes directly under the fascia of the forearm and shoulder, it can flow into the axillary vein. The topography of the connections between the lateral and medial subcutaneous veins is highly variable. The following most frequent forms of intervenous connections of superficial veins of the forearm are described.

1. The lateral subcutaneous vein of the arm goes obliquely upward through the ulnar fossa, it falls at the level of the lower third of the shoulder into the medial subcutaneous vein of the arm. The intermediate vein of the elbow is absent, the intermediate vein of the forearm empties into the fusion of the lateral and medial subcutaneous veins or into one of them.
2. Sometimes there is a significantly developed intermediate vein of the forearm. It can bifurcate, falls into two parts separately into the lateral and medial subcutaneous veins of the arms or, without dividing, opens into one of them. It is possible that the intervening vein of the forearm directly into one of the shoulder veins. The diameter and number of deep veins of the forearm are variable.

The lower vena cava is rarely doubled. Inflows of it can be additional renal veins, separate thin inflows of the portal vein.

Hepatic veins sometimes form one short trunk - a common hepatic vein flowing into the right atrium, with the lower hollow vein opening into the unpaired or umbilical vein. The umbilical vein is often preserved all over, drawing blood to the lower vena cava. The number, diameter of the renal, testicle (ovarian) veins are variable. The number of lumbar veins can be from one to six.

General, external and internal iliac veins can form local extensions.

The large subcutaneous vein of the leg is sometimes very thin, often doubled, less often triplicated. Sometimes it falls into the small saphenous vein of the leg. Often there is an additional subcutaneous vein of the thigh that collects blood from the medial or posterior side of the thigh. This vein flows into the large subcutaneous vein of the foot and is extremely rare in the femoral vein itself. There is a subcutaneous vein located on the lateral surface of the thigh. It flows into the large subcutaneous vein of the foot near the subcutaneous cleft, the so-called oval fossa. Sometimes there are two trunks of a small saphenous vein of the leg, connected by numerous transverse anastomoses. A small subcutaneous vein of the leg can flow into the large subcutaneous or deep vein of the thigh.

The popliteal and femoral veins are sometimes doubled. The severity of their tributaries is variable.

The portal vein has a different length and diameter. Its additional tributaries are the additional splenic, pancreatic-duodenal and right gastro-omental veins. In the upper mesenteric vein, a short trunk of the pancreas-duodenum vein sometimes flows. In the splenic vein, the veins of the cardiac part of the stomach often open.