Term
Describe briefly the primitive embryologic heart and veins |
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Definition
The two common cardinal veins merge to form the Sinus venosus, the primitive heart The common cardinal veins are formed from the ant and posterior cardinal veins (right and left) |
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Term
What drains at the junction of the right and left common cardinal veins and what happens to these vessels? |
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Definition
The vitelline and umbilical veins The vitelline veins eventually drain the intestine The left umbilical vein drains the placenta |
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Term
Generally what do the anterior cardinal veins form? |
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Definition
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Term
What happens to the majority of the posterior cardinal veins? What two major venous systems come off the posterior cardinal veins? |
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Definition
They regress Part of the azygos system The confluence of the common iliac and iliac veins |
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Term
Where do the majority of the veins below the heart develop from? |
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Definition
The sub and supracardinal veins |
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Term
Which side right or left of the cardinal veins persist? What is a way of remembering which form which vessels? |
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Definition
The right cardinal veins persist (sub supra etc) Sub is the opposite and forms the highest veins eg Right subcardinal vein forms suprarenal segment of IVC Infrarenal segment IVC comes from Right supracardinal vein |
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Term
What are the two components of the intima? |
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Definition
Endothelial cells and thin connective tissue |
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Term
How are valves formed and how does this affect their histology? |
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Definition
Infolding of intima Both sides of valves have endothelium with thin connective tissue skeleton |
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Term
Only some venous valves are bicuspid T or F? |
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Definition
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Term
What layer lies between the intima and media? Describe its composition |
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Definition
Internal elastic lamina Thick elastic fibers |
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Term
How does the internal elastic lamina vary in different size veins? |
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Definition
In large veins it is well developed Incomplete in medium sized veins and absent in small veins |
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Term
Describe the composition of the media in veins |
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Definition
Smooth muscle cells and and connective tissue fibers most of which is collagen |
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Term
Describe the histologic makeup of the media in the following veins and what effect it may have on function or dysfunction if any GSV GSV tributaries Deep calf veins Central deep veins such as femoral iliac and axillary and subclavian Superior and inferior vena cava |
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Definition
GSV - thick muscular media allowing contraction Tributaries-thiner media making them prone to varicosity Calf veins-high in collagen giving them greater wall strength Deep veins less smooth muscle Vena cava almost all connective tissue |
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Term
What does the adventitia layer of veins consist of? |
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Definition
Loose connective tissue with vasa vasorum and nerve fibers |
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Term
Which veins are valveless? Which has only one valve? |
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Definition
The IVC and Common Iliac veins The external iliac has only one valve |
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Term
What is the incidence of duplicate GSV in the thigh? |
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Definition
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Term
Name the 3 branches that join the GSV at the SFJ |
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Definition
Supericial epigastric External pudendal Superficial Circumflex iliac |
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Term
Name the two sets of lower leg perforators and the veins to which they connect |
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Definition
Posterior tibial perforators connect the posterior tibial veins to the posterior accessory vein (arcuate?) The paratibial peroforators connect the posterior tibial veins to the GSV which runs more anterior toward the anterior border of the medial malleolus |
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Term
Approximately how many valves are located in the GSV? |
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Definition
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Term
Which perforaors are valveless? |
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Definition
Small perforators, perforators of the foot |
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Term
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Definition
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Term
Define telangiectasias by size, color Venulectasias Reticular veins |
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Definition
Usually red 0.1-1mm 1-2mm Blue venules 1-4mm |
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Term
What percent of the population does the small saphenous vein not terminate into the popliteal vein? |
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Definition
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Term
What is the origin of the small saphenous vein? |
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Definition
Dorsal venous arch of the foot |
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Term
What % of blood volume is found in the veins? When assuming the upright position how many cc of blood enters the lower extremities? |
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Definition
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Term
What flow velocity in cm/sec is necessary for venous valve closure |
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Definition
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Term
The gastrocnemius and soleal veins are formed from which vessels? Which crural vein is most often involved in DVT and why? |
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Definition
The venous sinusoids The peroneal vein because it communication with the gastrocnemius veins which communicate with the venous sinusoids |
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Term
On average how many perforating veins are there in the leg? What are the two types of perforators and how are they defined? Where are perforators valveless? |
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Definition
100 Direct connect without interruption Indirect connect via muscular venous channels foot |
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Term
Define the two anatomical perforators of the lower leg by their new nomenclature, location and which vessels they connect |
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Definition
Paratibial perforators - upper medial lower leg connect main trunk or tributaries of GSV with posterior tibial veins Posterior tibial perforators (Cockett)-lower medial leg connect the posterior accessory GSV (old posterior arch vein) with the posterior tibial veins |
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Term
Do valves have vessels Y No |
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Definition
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Term
What clinical implications does the cranial extension of the SSV have? |
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Definition
It may lie close to the sciatic nerve and varicosities here may cause sciatic like symptoms |
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Term
Define the anatomy of the foot veins, their arches and what vessels they produce |
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Definition
Superficial Dorsal Venous Arch superficial without fascia covering it "Mother of two saphenous systems" medial limb continues up as GSV Lateral as SSV Deep plantar venous arch Drains blood from the muscular veins and superficial tissues of sole. Medial and lateral limbs come together beneath the medial malleolus to continue as paired posterior tibial veins. At first interosseus space there is a large valveless perforating vein which joins the deep and superficial arches. The interdigital perforating vein is the origin of the paired anterior tibial veins |
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Term
What defines the foot pump? How is blood expelled from the pump? |
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Definition
Foot pump is made up of the deep plantar arch Blood is expelled by stretching the veins by weight bearing not muscle contraction |
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Term
Describe the vein wall changes that occur with varicose veins |
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Definition
There is increased deposit and infiltration of collagen between muscle cells which disrupts the vein wall muscle grid. This leads to vein wall weakening and expansion of the valve annulus resulting in focal vein dilitation and valvular reflux Primary venous insufficiency is a result of abnormal connective tissue deposition and vein wall loss of integrity not valve leaflet function. |
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Term
Describe in detail the action of the calf muscle pump in sequence |
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Definition
Initial phase: distal calf pump is activated by dorsiflexion of the foot as the leg is lifted to take a step. Contraction of the anterior compartment muscles dorsiflexes the foot and empties the anterior tibial veins Dorsiflexion passively tightens the achilles tendo which empties the posterior tibial and peroneal veins which also As th foot strike s the ground weight bearing activates the second phase, foot pump (prev described) Plantar flexion intitates the third phase as the foot comes up on its toes. Contraction of the muscles of the posterior compartments particularly the soleus and gastrocnemius empties the proximal venous reservoir. |
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Term
What % of the blood volume rests in the veins? |
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Definition
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Term
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Definition
Top is normal with gradual rise in venous pressures Bottom is abnormal with steeper rise in pressure |
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Term
Where does the thoracic duct usually empty? |
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Definition
At the junction of the left subclavian and left internal jugular veins |
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Term
What is the average total lymph fluid daily? What is the average total lymph flow rate? |
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Definition
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Term
What anatomical changes in composition has been found in the vein wall of even normal veins in individuals with varicose veins |
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Definition
Increase in collagen, decrease in elastin |
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