Abd Vessel Doppler Flow Pt 3 PDF

Spontane ous Shunting- venous collaterals Pg. 224  Spontaneous Shunting 1.Gastroesophageal: collaterals arise (varices) in the submucosa of the esophagus where the esophageal branches of the Left Gastric Vein form anastomoses with the hemiazygous and azygos veins....

Spontane ous Shunting- venous collaterals Pg. 224  Spontaneous Shunting 1.Gastroesophageal: collaterals arise (varices) in the submucosa of the esophagus where the esophageal branches of the Left Gastric Vein form anastomoses with the hemiazygous and azygos veins. 2  Spontaneous Shunting 2. Paraumbilical Vein: looks like continuation of Left Portal Vein and extends down anterior abdominal wall to umbilicus. If not recannalized (patent) known as the Ligamentum Teres (pg. 209) Recanalized Umbilical Vein Pg. 226 Fig. 9-39  Spontaneous Shunting 3. Hemorrhoidal Anastomoses: Occur between the superior and middle hemorrhoidal veins. 5  Spontaneous Shunting Retroperitoneal Anastomoses: See small vessels around pancreas. Dilation of vessels may cause thickening of omentum- especially in children Use Doppler to distinguish from nodes These all occur in the body’s attempt to decompress portal hypertension.  Surgical Porto-Systemic Shunts 1. Portacaval- PV drains into IVC 2. Mesocaval- SMV drains into IVC 3. Splenorenal- Splenic Vein drains into Lt Renal vein 4. TIPS-Transjugular Intrahepatic Portosystemic shunt catheters are placed in the liver to drain from portal veins into hepatic veins Can verify patency of each of these with 7 Mesocaval Shunt Pg. 229 Fig. 9-41 TIPS Pg. 229 Fig. 9-42  Abdominal Aortic Aneurysm (AAA)- Aneurysm=a permanent localized dilation of an artery, with an increase in diameter of greater than 1.5 times its normal diameter 10  Abdominal Aortic Aneurysm (AAA)- Occurs in 5-7% of people over the age of 60 in the USA. People at High risk: Over age 60 Have Hypertension Smokers Have Vascular Disease (Coronary or Peripheral) Diagnosis often made by Dr. feeling pulsatile abdominal mass Abdominal Aortic Aneurysm- AAA Three predisposing factors: 1.Arteriosclerosis—most common 2.Syphilis 3.Trauma 12 Abdominal Aortic Aneurysm- AAA Clinical Symptoms: -may impinge on adjacent structures-- obstruction -may occlude a vessel and cause an embolism if it ruptures—intense back pain, drop in Hematocrit (45% of total blood volume, Red blood cells + White Blood Cells + Platlets) - 75% are asymptomatic *Ultrasound is method of choice to follow AAA’s Classification of Aneurysms 1. True Aneurysm 2. False Aneurysm(pseudoaneurysm)  True Aneurysms Lined by all 3 layers of the aorta Forms when the wall of the vessel gets weak Some occur secondary to underlying heart diseases  False Aneurysms (pseudoaneurysm) Not lined by all 3 layers of the Aorta A pulsatile hematoma that results from leakage of blood into the soft tissue abutting the punctured artery, with subsequent fibrous encapsulation and failure of the vessel wall to heal. Can occur after trauma by an accident or surgery or interventional cardiac catheterization or angiography procedure With color Doppler can see flow into protuberance during systole and out during diastole True v.s False Aneurysm Pg. 163 Fig. 8- 36 True False/pseudoaneurysm Descriptions of Aneurysms 1.Fusiform: most common presentation usually of the distal aorta at the bifurcation diffuse dilation of the vessel Elongated and tapering at both ends (spindle shaped) 18  Descriptions of Aneurysms 2. Saccular: larger than fusiform connected to the vessel lumen by a “mouth” or “stalk” may be partially or completely filled with thrombus can be very difficult to differentiate from a retroperitoneal mass or lymphadenopathy Descriptions of Aneurysms Pg. 163 Fig. 8- 37 20  Locations of Aortic Aneurysms 1.Infrarenal—located below the origin of the renal arteries (most common) 2.Perirenal—involves the level of the origin of the renal arteries— hard to repair 3.Suprarenal—located above the renal artery origins-may extend above diaphragm 21  Growth Patterns for Abdominal Aneurysms The normal aortic lumen diameter= Less than 3cm Ultrasound has a 98.8% accuracy rate for detecting aortic aneurysms (provided good technique is used)Therefore Ultrasound is the modality of choice for imaging. If the aneurysm is less than 6cm, it will have a very slow growth pattern, so the 22 patient is re-evaluated each year.  AAA Statistics * 75% of patients will survive for a year if the AAA is less than 6cm *50% of patients will survive for a year if the AAA greater than 6cm *25% of patients will survive for a year if the AAA greater than 7cm There is a 75% risk of fatal rupture if the AAA is greater than 7cm 23  AAA Statistics *1% of AAA (Less than )