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PART 5 — ABDOMINAL
Azygos vein
Left hemiazygos vein
Para-umbilical veins
Veins of Sappey
Diaphragm
Liver
Portal vein Right gastric vein
Inferior vena cava Right gastroepiploic vein
Abdominal wall Superior mesenteric vein
Right colic vein Veins of Retzius
Caput medusae
IIeocolic vein IIiac veins
Epigastric vein Subcutaneous abdominal vein
Small bowel Spermatic vein (gonadal)
Esophageal anastomoses Esophageal varices
Intercostal vein
Left gastric vein Stomach
Short gastric veins
Left gastroepiploic vein
Spleen Splenic vein
Spontaneous splenorenal shunt
Left renal vein Left kidney Left colon
Left colic vein Abdominal wall
Retroperitoneal anastomoses Inferior mesenteric vein
Superior rectal vein (hemorrhoidal) Rectum
Inferior rectal vein (hemorrhoidal)
Rectal anastomoses
Figure 22-11 A diagram depicting the various portosystemic collaterals.
the risks of surgery and general anesthesia. The tran- sjugular intrahepatic portosystemic (also known as portocaval) shunt or TIPS procedure has replaced the need for surgically created shunts in most patients.
Via jugular vein cannulation, a stent is deployed connecting one of the portal veins (often the right portal vein) with one of the hepatic veins (often the right hepatic vein). This has the effect of rerouting blood flow away from the liver, out through the stent,
into the hepatic vein, and back to the heart. The stents employed had been bare metal stents but many are now created using partially covered stents.15
The ultrasound techniques employed to evalu- ate a patient with a TIPS are much the same as a conventional evaluation of the native portal system. These include the same transducers and scanning approaches, as well as the same patient preparation of having the patient fast prior to the ultrasound.