Vascular Final Review

Turbulent flow:

-Abnormal narrowing (stenosis) causing turbulent flow may be with eddy currents after stenotic region obliterating the streamlines. -Flow in all directions at varying speeds - chaotic flow or vortex (swirling pattern).

Thromboangitis:

-Aka Buerger's disease. -A disease caused by the inflammation of the arteries/veins preventing blood flow. -Always start distally and moves proximally (toes and hangs will be cold). -There are no collaterals seen in this disease. -May have ischemic rest pain. -Is associated with heavy smoking. -May often associated with rheumatoid arthritis. -Occurs primarily in young men < 40 years.

What is reactive hyperemia, and who is the candidate for this examination?

-Aka Post Occlusive Reactive Hyperemia (PORH) -Patient qualify for reactive hyperemia: for the following reasons: Patient cannot ambulate/walk Has heart disease/cardiac murmur Poor cardiac output Pulmonary problems Stroke or paralysis

Raynaud's Syndrome: Secondary:

-Aka Raynaud's phenomenon or obstructive Raynaud's Syndrome. -Consists of a normal vasoconstrictive response in arterioles and capillaries superimposed on a pervious arterial obstruction or disease. -Progressive condition. -Ischemia is constantly present. -Increased capillary refill time. -Hands and feet always stay cold and eventually may lead to rest pain.

Laminar flow:

-Aka parabolic flow. -Normal flow in the arteries consisting of many laminae (layers). -Each layer is thought to flow at a different velocity. -The velocity of each layer increases as they approach the center of the lumen due to minimum frictional resistance. -Speed of flow is fastest in the center and slowest near the vessel walls. -Parabolic flow is used for velocity measurements.

Takayasu Arteritis:

-Aka pulselessness disease (because of less flow volume). -A giant cell arthritis that affect the aortic arch and large vessels that originate from it. -Inflammation of intima and media causes a narrowing of the lumen. -Usually found in females and asian ages 15 to 48 years. -Causes decreased blood flow to arms and produces pain upon exercise or at rest.

Posterior enhancement:

-An artifact caused by weak attenuating structure like fluid filled structures (cyst or bladder) that cannot attenuate the sound. -It is also known as through transmission.

Aliasing:

-An artifact that is caused by under-sampling or low scale setting. -It indicates high velocity flow that is normally seen at stenosis.

Atherosclerosis Obliterans (ASO):

-An endothelial injury followed by low density lipoproteins (LDL) into the intima. -Number 1 cause for atherosclerosis: hypertension (increased pressure to vessel walls causes injury to the intima). -Atherosclerosis is a form of arteriosclerosis that brings changes to the intima as a result of focal accumulation of lipids (atheroma), complex carbohydrates, fibrous tissue, calcium deposits, and platelets (cellular debris). -Inflammatory response with smooth muscle cell proliferation in the media. -Plaque protrudes into the arterial lumen which may become altered by hemorrhage, cell necrosis, calcification, or ulceration. -It causes stenosis, occlusion, embolism, hardening of the vessel, and aneurysm.

Thoracic outlet syndrome:

-An extra rib in the thorax (cervical rib) or Scalene muscles cause extrinsic compression on distal SCA or proximal axillary artery is position dependent. Anatomical structural deformity. -More common in female ages 20-40 years of age. -Symptoms: Pain in the neck. UE pains and weakness/fatigue/clumsiness. Parasthesia of shoulder/arm. Intermittent weakness during exercise. Headache.

Fibromuscular dysplasia:

-An overgrowth of collagen in the media layer of the vessel. -Most commonly caused by dysplasia (lack of growth of cells) of tunica media with an overgrowth of collagen (connective tissue). -More common in young females. -Creates segmental narrowing of the vessel wall which appears as a "string of beads" in angiography (best seen).

What vessels are parts of anterior circulation?

-Anterior circulatory system: (provides 75% of the blood supply to the brain). Intracranial: ACA MCA Extracranial: CCA ICA ECA

Disturbed flow:

-Any change in direction of the vessel, increased velocities and altered vessel geometry can lead to flow disturbance of the layers (laminae). -Streamlines persist but waves and irregularities can be seen within the flow.

Subclavian steal syndrome:

-Blockage of plaque at the proximal point of subclavian arteries before vertebral bifurcation. -A condition in which blood that is destined for the brain is shunted (redirected) away from the cerebral circulation because the subclavian artery or innominate artery has high grade stenosis or occlusion, proximal to vertebral artery origin and blood is going to brachial artery. -Retrograde flow in the vertebral. -Subclavian steal is stealing the blood from the brain and feeding the arm. -Steal is always in the area of lower blood pressure. -If the difference of BP for both brachial artery is > 20 mmHg, then the side with the lower number is the area of steal. -If the pressure gradient is > 30 mmHg between upper arm (brachial to brachial) pressures (rt and lt) indicates at least a 50% DR in the lower number side vertebral artery.

Popliteal Entrapment:

-By the gastrocnemius muscle. -Rare. -Due to an abnormal insertion of the muscle, compressing the POPA. -Usually occurs in young athletic men. -Can be bilateral.

Medial calcinosis:

-Calcification of media layer due to pre existing condition like diabetes. -It causes hardening of the vessel and leads to uncontrollable hypertension.

Steps for calculating DSP:

-Calculate ABI. -If abnormal then check segmental pressures on the affected limb. -Compare the segmental pressures: -The high thigh should be more than 30 mmHg than the highest brachial artery. -Each adjacent vertical segment of the leg should not be more than 20 mmHg. -Disease is present at and above the lower pressure cuff.

Resistive index:

-Calculates the resistance present in arteries. -Resistive index = PSV - EDV/PSV -Normal renal RI = < 0.7 - 70%

Raynaud's Syndrome:

-Defined as episodic digital pallor, cyanosis, or both. -Involves the constriction of blood supply to the hands. -Caused by high emotional stress, anxiety, or cold temperature. -PVR waveform: The dicrotic notch is found very close to the peak of the waveforms.

PPG (Arterial):

-Detects cutaneous blood flow and records pulsations. -A photo cell is attached to the distal portion of the underside of a digit. -The photo cell sends an inferred light into the tissue with a light emitting diode. -The photo cell also receives the backscattered light from the blood flowing through the vessels and its reflection is displayed as waveform.

Collaterals:

-Develops slowly overtime/progressively in chronic cases. -Ability to develop collaterals is variable. -Not seen in acute cases. -If collaterals are present then patient may not present symptoms (natural grafts).

PPG (Venous insufficiency/valvular incompetence) (Photoplethysmography) (DC setting):

-Evaluate both superficial and deep system. -Records reflection of infrared light and documents capillary blood volume, valvular competence and evaluates venous insufficiency. -Checks the empty and refill proportional time. -Method: -Patient position: Sitting with legs dangling (non-weight bearing). -PPG sensor is placed 2-3 cm above medial malleolus (below the knee/calf). -Patient performs 5 dorsiflexions of foot (to empty the vein by pumping the calf muscles). -PPG are used to record the venous refill time (VRT). -If the VRT is >20 seconds the result is normal. -If the VRT is <20 seconds the result is abnormal. -If valves leaking there will be reflux with dorsiflexion and calf will not empty itself.

Pseudoaneurysm:

-False aneurysm caused by injury to the vessel. -A small pocket of moving blood connected to an artery. -May be surrounded by thrombus. -Usually due to needle procedures like: cauterization, cyst aspirations, surgery, or trauma. -Felt as pulsatile mass (pulsatile hematoma). -Appears as "ying-yang" sign in transverse plane in ultrasound. -In spectral doppler is appears as "to and fro" flow pattern.

Saccular aneurysm:

-Focal out pouching involving only one side of the vessel wall. -Usually found in left lateral distal aorta (just above bifurcation or left CIA). -May have thrombus.

Raynaud's Syndrome: Primary:

-Is found in female under 40 years. -Occurs bilaterally. -Changes in skin color (white to blue to red). -Intermittent digital ischemia caused by digital arterial spasm.

PVR- normal / abnormal waveform:

-It is used in conjunction with other tests like: DSP (Doppler Segmental Pressures). -It detects significant volume changes within each limb segment by sensing the expansion of the vessel. -Those instantaneous pressure changes are recorded as waveforms.

Allen test:

-It is used to determine if the radial or ulnar artery is occluded. -Method: Patient clenches his/her hands tightly. Pinch off the radial or ulnar artery with your thumb. Allow patient to open their hand. -Results: If blood flow returns to the hand (hand turns red) then: The artery which is not pressed is not occluded and is the provider of the blood flow. If the hand turns white after opening the hand and compression then: The artery which is not pressed is occluded.

Mesenteric Ischemia:

-Lack of blood flow to the intestines. -Claudication (pain) in abdomen 20 minutes after eating. -SMA resistance stay high after eating.

Vertigo:

-Loss of balance, difficulty in maintaining equilibrium. -Feeling that you are moving around in space or having objects more around you in space.

IPG (Impedance (resistance) Plethysmography):

-Most common indirect exam. -Checks volume changes in veins. -Measure the rate at which blood leaves the legs via veins. -Method: -A thigh cuff is inflated to 50 mmHg which occludes venous flow not arterial. -4 electrodes are placed on patients calf. -The leg swells and the change in volume is plotted as a waveform. -SVC (segmental venous capacity) = distance in mm. -The thigh cuff is released after 30 - 45 seconds when waveform gets stable (plateau), then release pressure by deflating the cuff. -Waveform returns to the baseline quickly as blood exits the leg and flows towards the heart on deflation of the thigh cuff. -The amount of change following cuff release, in a 3 second period called "maximum venous outflow" (MVO). -Shorter time for MVO indicates no obstruction or DVT. -If vein is blocked MVO increases.

RIND (Resolving Ischemic Neurological Deficit):

-Neurological deficit symptoms appear suddenly and last for more than 24 hours but less than 72 hours. -Patient returns to normal.

Pulsatility index:

-PI means there is flexibility of the vessel. -Higher PI means: +Compliance of the vessel to cardiac cycle. +Flexibility that means healthy vessel. -Lower PI means: +Indicates proximal occlusive disease. +Hardening of the vessel disease. PI = peak to peak frequency/mean frequency

Pulsatility index (high and low):

-PI means there is flexibility of the vessel. -In the absence of SFA disease, PI of less than 5 suggests aorta-iliac disease. -These values decrease in proximal vascular disease (damp signal). -Lower values - indicates proximal occlusive disease and hardening of the vessel disease. -Higher values - indicates compliance of the vessel to cardiac cycle and flexibility that means healthy vessel. -Differentiate between inflow (coming from stenosis; damp signal) (aortoiliac) to outflow (going towards the stenosis; high resistance) (femoral) disease. -Normal PI: CFA = > 5.5 POP = > 8.0 PI = peak to peak frequency/mean frequency

List the reasons for the blood to flow in the vessels?

-Patent lumen of the vessel. -Pressure gradient/difference (blood is gonna flow from high to low).

What is ABI and how is it performed and calculated?

-Patient position: supine. -Blood pressure is taken bilaterally on the brachial arteries by inflating pressure cuffs 20-30 mmHg greater than the last pulse. -Then release pressure - first sound heard is the peak systolic pressure. -BP is also taken bilaterally at the ankles using a CW probe on the PTA or the dorsalis pedis artery. ABI = ankle pressure (highest of either PTA or dorsalis) / highest brachial pressure

Poiseuille's law:

-Poiseuille's law helps to determine how much fluid is moving through a vessel (quantify). -It describes the relationship between resistance, pressure, and volume flow. Volume flow rate = pressure difference x ℙ x radius⁴/8 x viscosity x vessel length Unit: ml/sec

What vessels are parts of posterior circulation?

-Posterior circulatory system: (provides 25% of the blood supply). -Aka Vertebrobasilar circulation. -Supplies blood to the posterior 1/3 of the brain. -Blood supply comes from: Intracranial: PCA Basilar artery Extracranial: Vertebral artery

Reynolds Number:

-Predicts the onset of turbulent flow. -If Reynold's number exceeds 2000 - there will be turbulent flow. Reynold's number = velocity x diameter x density/viscosity

Bernoulli Principal:

-Pressure drops and velocity increases at stenosis to compensate the loss of diameter to maintain continuity rule (constant blood flow). HDSL - (50% to 75% DR —> 75% AR to 94% AR).

Factors that affect resistance:

-Resistance is affected by 3 factors: Length Viscosity Radius Resistance = 8 x length x viscosity / 3.14 x radius⁴

Bruit:

-Sound of eddy current, tortuous vessels, or vibration of the vessel wall that is picked up by a stethoscope. -Bruit can be heard: After stenosis Dissection of the vessel Cardiovascular disease AVF or AVM

Fusiform aneurysm:

-Symmetrical uniform dilation involving all three layers and both sides of the vessel wall. -Usually found infra-renally. -May contain thrombus.

Compartment syndrome:

-Symptoms are produced by an obstruction of a portion of the blood supply and increased pressure (usually in the calf) due to DVT, hemorrhage, edema, lymph fluid collection. -Treatment: Surgical opening of the compartment to relieve pressure.

TIA (Transient Ischemic Attack):

-Symptoms of neurological deficit appear suddenly and last for a few minutes (usually 20 min) and reverse itself within 24 hours. -Causes no lasting effect (mini stroke). -Increases more risk of stroke after TIA.

Dissecting aneurysm:

-Tear in intimal lining of the vessel wall separates intima from media layer. -A false lumen is created in between intima and media causing inflammation of the media. -Flap may occlude the vessel and cause cardiac abnormalities. -Most common site is - in thoracic/descending aorta and patient presents with the symptom of chest pain.

Draw and label the arteries of the upper extremities:

-The left subclavian artery (SCA) branches directly off of the aortic arch on the left. -On the right, the brachiocephalic/innominate artery branches directly off the aortic arch and then turns into the RSCA. -The SCA turns into the axillary artery at the lateral level of the first rib. -The axillary artery becomes the brachial artery as it courses over the proximal humerus bone and can be followed down the arm to the antecubital fossa where is bifurcates into the radial and ulnar branches. -The radial and ulnar arteries branch into the superficial palmer (volar) arch and the deep palmar (volar) arch. -These branches into digital arteries.

What are the 4 branches of Ophthalmic artery?

-The ophthalmic artery: the first branch that branches off from ICA at Cavernous siphon portion. -It has 4 branches: +Lacrimal (central retinal) artery: Supplies blood to the eyes. +Supraorbital artery: Joins the ECA via the superficial temporal artery. +Frontal artery: This artery exits the orbit medially to supply the mid portion of the forehead. It joins the ECA via the superficial temporal artery as well. +Nasal artery/angular artery: Branches off the frontal artery to supply blood to the nose. It joins the ECA via the facial artery.

Vaso vasorum:

-This is a network of tiny blood vessels that perfuse the tissues of blood vessels themselves specially tunica media and adventitia. -Tunica intima gets its blood supply from the blood flowing through it.

Vasoconstriction:

-Vasoconstriction is narrowing of the vessel lumen caused by contraction of the muscular wall increasing the pulsatility in small and medium sized arteries. -It dilates the arterioles to maintain the continuity of flow and that decreases the pulsatility of flow in arterioles making it steady flow (due to arteriole dilation). -It results in decreased blood flow in capillaries resulting in cold hands and feet.

Positive Doppler shift:

-When the received frequency is greater than the source frequency/initial frequency. -It happens for an approaching reflector. -Flow is towards the transducer.

Negative Doppler shift:

-When the received frequency is smaller than the initial frequency. -Flow is going away from the transducer.

Vasodilatation:

-When the smooth muscle relaxes. -Vasodilation is enlargement of vessel caused by relaxation of the muscular vessel wall. -Vasodilation causes a decrease in puslatility in small and medium sized arteries resulting in more blood flow volume. -It increases the blood flow in arterioles that increases the pulsatility in arterioles, and increases the blood flow in capillaries resulting in feeling hot and sweaty.

Draw the vessels included in the Circle of Willis, including blood flow direction:

1. Anterior cerebral artery (ACA): Carries 20% - 30% of the blood to the brain. 2. Middle cerebral artery (MCA): Carries 70% - 80% of the blood to the brain. 3. Posterior cerebral artery (PCA): Feeds posterior brain. 4. Basilar artery: Formed by the vertebral arteries, and supplies blood to the posterior structures of the cranial cavity. 5. Distal ICA: Feeds anterior circulation of the brain by terminating into ACA and MCA. 6. Anterior communicating artery (ACoA): Connects right brain circulation with left brain circulation. 7. Posterior communicating artery (PCoA): Connects anterior circulation with posterior circulation.

Draw and label the branches of the Abdominal Aorta:

1. Celiac axis: First branch off of the abdominal aorta. Feeds the stomach, spleen, liver, pancreas, duodenum. 2. SMA: Superior Mesenteric Artery: One cm distal to celiac axis. Feeds pancreas, small intestines, ascending colon, cecum, and part of transverse colon. 3. Renal arteries: Supply kidney, ureters, and adrenal glands. Exit aorta laterally towards the kidneys. 4. Gonadal arteries: Feeds the ovaries in female and testicles in men. 5. IMA: Inferior Mesenteric Artery: 3 - 4 cm above the aortic bifurcation. Supplies descending iliac and sigmoid colon as well as the left half of the transverse colon and upper part of rectum.

Draw and label the arteries of the lower extremities:

1. Common femoral arteries (CFA): Formed from the EIA beneath the inguinal ligament, coursing lateral to the CFV. Its 5 cm of length before it bifurcates into DFA and SFA. 2. Deep femoral artery (DFA) aka profunda femoris: Courses posteriolateral at its origin and continues medial to the femur where it terminates as the perforating artery. Supplies blood to the thigh muscles and hip joint. Its muscular branches are a critical collateral source in superficial femoral artery obstruction. 3. Superficial femoral artery (SFA): Originates 4 cm below the inguinal ligament, arising from the CFA. Courses along the mid aspect of the thigh at the level of the Adductor hiatus, in the tendon of Hunter's canal and enters popliteal fossa (behind the knee) and becomes popliteal artery. 4. Popliteal artery (POP A): Begins at the adductor hiatus, descends lateral and bifurcates just below knee into anterior tibial artery and tibioperoneal trunk. Supplies blood to the knee region and calf muscles. 5. Anterior tibial artery (ATA): First branch off the distal popliteal artery. Courses between the tibia and fibula terminating at the dorsalis pedal artery on the anterior surface of the foot. Feeds the anterior lateral aspect of the leg and parts of the foot. 6. Tibioperoneal trunk aka proximal posterior tibial artery: Second branch off the distal popliteal artery, which divides into the peroneal and posterior tibial arteries. 7. Posterior tibial artery (PTA): Courses posterior to the tibia, behind the medial malleolus. Terminates into medial, lateral, and plantar arteries of the foot. Feeds the medial aspect of the lower leg and foot. 8. Peroneal artery: Lies adjacent to the border of the fibula. Supplies the lateral aspect of the leg and foot. 9. Dorsalis pedis artery: ATA comes on lateral aspect of ankle and becomes dorsalis pedis artery which branches into: Deep plantar artery Metatarsals

What is a normal /abnormal ABI range?

> 0.96 to 1.3 normal 0.50 to 0.95 mild (single segment disease - claudication) 0.21 to 0.49 moderate (multi segment disease - rest pain) ≤ 0.20 severe (ischemia/tissue loss/necrosis) 1.3 to 1.5 incompressible vessel (falsely elevated)

The Doppler Effect:

A change in received frequency as a result of a relative motion (of sound source or receiver or reflector).

Triphasic flow:

A wave with 3 parts: Above the baseline. Slight reversal flow. Slight forward flow above the baseline.

Acceleration Time (Normal / abnormal):

AT means the time from the beginning of the pulse to the peak systole.

Which vessel changes its resistance from high to low and what causes this change in resistance in that vessel?

All the vessels that feed gastrointestinal track like superior mesenteric artery and inferior mesenteric artery.

Posterior shadowing:

An artifact caused by highly attenuating structures like calcified plaque or stone that causes total attenuation of sound.

What are the various types bypass grafts and how are they different?

Bypass grafts can be: Synthetic (man-made): Gore-tex and Dacron Reversed vein (saphenous) grafts: Patient's own vein is harvested for graft without removing valves. Surgical removal of the greater saphenous vein and ligation of all branches. In-situ grafts: The greater saphenous vein is left in place and anastomosed to the affected artery. The valves of the vein are surgically removed and the branches ligated.

What is the most likely location and the least likely location for the plaque to form in the body?

Carotid bifurcation Infrarenal Aortic bifurcation Popliteal bifurcation Upper extremities

What is the first branch of the ICA?

Cavernous Siphon or Carotid Siphon section gives way to Ophthalmic artery - first branch of ICA.

Who is most likely to have an aneurysm?

Congenital weakness of the vessel Hypertension Trauma Surgery Atherosclerosis Smoking

What are the controllable and uncontrollable risk factors for CVA's?

Controllable risk factors: Diabetes: Contributes to the hardening of the arterial wall (medial calcinosis). Smoking: A strong risk factor for the development of atherosclerosis. Hypertension: High blood pressure creates increased stress on arterial wall. Associated with the development of atherosclerosis (fatty, hardening of the blood vessels). Hyperlipidemia: High saturation of lipid fats in blood, which contributes to the development of atheromatous plaque (increased total cholesterol and LDL (low density lipids) in the blood). Non-controllable risk factors: Aging Family history/genetic predispositions Male gender

Draw the deep and superficial veins of the lower extremities:

Deep venous system: -Most of the blood returns to the heart from the deep venous system. 1. Deep digital veins - beginning of the venous return (from capillaries —> venules —> deep digital veins). 2. Deep digital veins though venous plantar arch drains into the calf veins. 3. Paired peroneal veins drain lateral aspect of calf and join tibioperoneal venous trunk. 4. Paired posterior tibial veins drain posterior aspect of calf and join the tibioperoneal venous trunk. 5. Paired anterior tibial veins drain anterior aspect of the calf and connect to popliteal vein. 6. Popliteal vein - confluence of anterior tibial veins and tibioperoneal trunk. 7. Popliteal vein becomes superficial femoral vein after passing through adductor hiatus (hunters canal). 8. DFV confluence with SFV and becomes common federal vein (CFV) after passing under inguinal ligament. 9. GSV also joins CFV at saphenofemoral junction. 10. CFV becomes external iliac vein (EIV) just above the inguinal ligament. 11. External iliac vein joins internal iliac veins unite at the level of L-4 - L-5 (umbilicus) to become the IVC. 12. Left common iliac vein travels posterior to the right common iliac artery to drain into inferior vena cava (IVC). 13. Left common iliac vein at the passing artery becomes the most common location for DVT.

Draw the deep and superficial veins of the upper extremities:

Deep venous system: -Starts in deep digital veins. -Continue to form palmar arches of hand. -Empty into paired radial and ulnar veins. 1. Radial and ulnar: Are paired with their respective artery. Paired radial veins drain lateral aspect of arm. Paired ulnar veins drain medial aspect of arm. Radial and ulnar veins travel up, come together to form paired brachial veins. 2. Brachial veins: Are paired with brachial artery. Joins with basilic vein to become the axillary vein. 3. Axillary veins: Travel adjacent to axillary artery. As it crosses the first rib, it becomes the subclavian vein after joining the cephalic vein. 4. Subclavian vein: Is found inferior and anterior to subclavian artery. It courses medially. Collapses on sniffing. Subclavian vein joins internal jugular vein bilaterally. 5. Internal jugular vein: Extends foramen at the base of skull, down the lateral aspects of the neck. Joins subclavian vein to form the brachiocephalic/innominate veins, and then drains into the right atrium of the heart. Superficial venous system: 1. Cephalic vein: Travels superficially up the lateral aspect of arms. Joins the subclavian vein. 2. Basilic vein: Travels superficially up the medial aspect of the arms. Joins with paired brachial veins.

Raynaud's Syndrome symptoms:

Digital color changes. Hand and foot numbness and tingling. Throbbing pain/burning sensation.

Diplopia:

Double vision (due to posterior circulation insufficiency).

List few examples of high resistance vessels in the body:

External carotid Aorta Iliac Subclavian Fasting superior mesenteric and inferior mesenteric All arteries of both extremities

List segments of ICA:

Extracranial: -Cervial - the longest portion (we scan at this level) and there are no branches at this level. Intracranial: -Petrous -Cavernous/Carotid siphon - S-shaped section that gives way to the first branch of ICA called - ophthalmic artery. -Supraclinoid - distal ICA terminates into ACA and MCA in this portion.

Retrograde flow:

Flow moving in opposite direction due to total blockage (occlusion) or reflux due to incompetent valve.

What are the common locations for each type of aneurysm?

Fusiform aneurysm: Usually found infra-renally. Saccular aneurysm: Usually found in left lateral distal aorta (just above bifurcation or left CIA). Dissecting aneurysm: Most common site is - in thoracic/descending aorta and patient presents with the symptom of chest pain. Pseudoaneurysm: Common site: at the site of puncture.

List ways to distinguish the ICA from the ECA:

ICA: - Larger size with bulbous area at the CCA bifurcation. - Posterior lateral position. - Low resistance flow. - No branching in cervical region (scanning area). ECA: - Smaller size. - Anterior medial position. - High resistance. - Branches seen in cervical region.

Resistance increases with:

Increasing length Increasing viscosity Decreasing radius

Flow increases with:

Increasing pressure gradient Decreasing resistance Q = pressure difference/resistance

Draw and label the vessels of the aortic arch:

Innominate/Brachiocephalic artery: First branch on the right side. Right CCA emerges from innominate artery which further bifurcates into right ICA and right ECA. Innominate artery becomes right subclavian artery after RCCA. Left common carotid artery: Second branch of the aortic arch that bifurcates into left ICA and left ECA. Left subclavian artery: Third branch of aortic arch. It gives way to the left vertebral artery.

List few examples of low resistance vessels in the body:

Internal carotid artery Renal artery Vertebral artery Hepatic artery Splenic artery Celiac arteries Post-prandial mesenteric arteries

Amaurosis Fugax:

Known as monocular blindness (unilateral) this is blindness in one half of the visual field.

Ataxia:

Loss of muscle coordination, gait disturbance.

How would you differentiate a high resistance flow from low resistance flow?

Low resistance flow: -Continuous and steady flow throughout systole and diastole. -The increased diastolic component indicates the vessel supplies to a low resistance (highly vascular) distal vascular bed with more constant flow. High resistance flow: -Flow is pulsatile (tri- or biphasic). -A decreased diastolic component indicates the vessel supplies a high resistance distal bed that has resistance to flow since constant flow is not necessary.

Tardus Parvus waveform:

Low velocity (dampened) and slow acceleration Tardus-parvus waveforms suggestive of proximal stenosis.

What are the branches of the celiac axis/trunk?

Lt. Gastric artery Splenic artery Common hepatic artery

What are the normal/ abnormal flow velocities in a Graft?

Normal: PSV between 100-200 cm/s with organized turbulence. The velocity tends to be higher in the first 6 months after the placement of the graft. Abnormal: Elevation of PSV by 100% (or ration of 2:1) indicates 50% DR. High grade stenosis is also probable with PSV less than 50 cm/s may indicate graft inflow disease or proximal disease. Damp signal in PW doppler indicates proximal blockage.

CVA (Cerebrovascular Attack):

Permanent neurological deficit causing irreversible symptoms.

List 4 different types of energies found in the body and describe each one of them:

Potential energy aka pressure energy: Main source of energy found in the body, begins in heart and is measured in mmHg. Kinetic energy aka velocity energy: Kinetic energy is associated with movement (velocity of flow). Hydrostatic energy aka gravitational energy: In the circulation system, the hydrostatic energy/pressure is equal to the weight of a column of blood, extending from the heart. It is affected by density of the blood, height of the patient and position of the patient.

Which is the main form of energy found in the body and measured as blood pressure?

Potential pressure is the main form of energy in the body and is measured as patient's blood pressure.

Measurements for a stenosis:

Pre-stenosis (proximal): Moderate or critical stenosis (HDSL) High resistance with decreased diastolic flow - (4D principle). At stenosis: Elevated PSV and EDV. Waveform indicates spectral broadening. Spectral window fill-in. Post stenosis (distal): Directly after: turbulence. Further past stenosis: Low resistance flow with tardus-parvus waveform (dampen signal).

List branches of the ECA:

S - Superior Thyroid artery A - Ascending pharyngeal artery L - Lingual artery F - Facial artery O - Occipital artery P - Posterior Auricular artery M - Maxillary artery S - Superficial temporal artery Some Angry Ladies Fight Off PMS

Monophasic flow:

Single peak waveform. Low resistance flow.

Aphasia:

Speech difficulties or language deficit. The patient has a problem with understanding or finding words. The casual lesion would be in the carotid artery supplying the dominant hemisphere (which is the left for most patients).

Endarterectomy:

Surgical removal of plaque.

What are the symptoms of Acute occlusive lower extremity arterial Disease?

Symptoms: the 6 "P's" Pain Parasthesia (numbness, tingling) Pulselessness (due to decrease flow volume) Paralysis or weakness of limb (paresis) Pallor (change in skin color - turns white) Poikilothermia (inability to maintain body temperature - cold)

Syncope:

Temporary loss of consciousness.

Raynaud's syndrome:

The dicrotic notch is found very close to the peak of the waveforms.

What is the relationship between Diameter Reduction and area reduction when measuring a stenosis?

The following ranges are called hemodynamically significant lesion (HDSL) where Bernoulli's law is applies. DR 50% -> AR 75% DR 75% -> AR 94%

What are the three layers of vessel?

Tunica intima/interna: The innermost layer composed of smooth endothelial cells. This layer is in contact with blood and plaque that forms in the vessel. Tunica media: This is the middle muscular layer composed of smooth muscle, connective tissue and elastic fibers arranged in a circular pattern. It is much thicker in arteries than in veins. It can change the size of arteries and gives them their rigidity and round shape. It is influenced by hormones and body chemicals. Tunica externa/adventitia: This is the outermost layer composed of collagenous fibrous connective tissue and smooth elastic fibers arranged longitudinally. It is thinner than the media. It provides strength, shape and protection to the arterial wall.

Biphasic flow:

Waveform with 2 parts: Above the baseline. Below the baseline.

The vertebral arteries arise from ___________ ______________ _______________ and they confluence to form ____________ _________________.

subclavian arteries bilaterally basilar artery