chapter 20 : venous valvular insufficiency testing

CVI (chronic venous insufficiency)

includes venous obstruction and or valvular insufficiency

pathologic reflux

must be differentiated from reverse flow that forces normal closure or fills veins segments between valves

aesthetic phlebology

is a term used to distinguish a visible condition from a truly symptomatic disorder

saphenous fascia

the saphenous veins lie within the — layers (give “eye” appearance)

GSV

courses medically in thigh and leg

anterior accessory saphenous vein (AASV)

is aligned with femoral artery and vein in a transverse plane; lies within a saphenous compartment

• courses anteriorly through thigh

posterior accessory saphenous vein (PASV)

courses posteriorly through thigh

• may connect with VOG

tributaries

vessels that drain into another major vein

• pierce saphenous fascia, enter the saphenous compartment, and drain into corresponding saphenous vein

ultrasound image of the alignment sign

bulging varicose veins

tributaries are often associated with —

ultrasound image of a tributary vein

angle sign

GSV below the knee is identified by —

angle sign is a triangular form between the

• gastrocnemius muscle

• tibial bone

• GSV within fascia

helps differentiate saphenous vein from prominent tributaries

ultrasound of the angle sign

 

segmental

most duplications are —; complete duplications are rare

parallel

to be duplicated, both saphenous veins must follow the same path and remain — within the fascia

saphenofemoral junction (SFJ)

• confluence of the GSV and common femoral vein

• contains terminal valve of the GSV

second valve (preterminal)

is distal to tributaries that join GSV and SFJ)

preterminal valves (?)

• superficial epigastric vein (SEV) (tributary used as landmark for treatment)

• superficial external pudendal vein

• superficial circumflex iliac vein

SSV confluence with deep system is variable

• popliteal vein at the saphenopopliteal junction

• gastrocnemius vein

• distal femoral vein of the thigh

• small unnamed deep vein

• perforating vein at the posterior thigh

• GSV via the VOG

venous valves

bicuspid valves with leaflets that point in the direction of normal venous drainage

heart

venous valves vary in number, increasing frequency with distance away from the —

contraction

venous valves open with muscular — and close with muscular relaxation

incompetent valves

allow abnormal retrograde flow

order of blood regulating the body

1. blood returns to skin

2. to tributaries

3. to saphenous veins

4. to perforators

5. to deep veins

6. to heart

50%

of people have CVI at some point during a person’s life span

without

venous insufficiency can be present — varicose veins

35%

reflux of the lower extremities is present in up to — of general population

• prevalence of reflux increases with age

highest

GSV shows the — prevalence of reflux

aesthetic phebology refers to visual signs and includes;

• spider veins

• telangiectasias

• reticular veins

• varicose veins

• edema (also a palpable sign)

• skin changes

• ulceration

edema

patients may have temporary swelling at the end of a workday, after prolonged standing, or as a consequence of certain activities or leg positioning

edema source must be differentiated; sources include (besides venous obstruction or insufficiency)

• lymphatic obstruction

• sympathetic tone

• cardiac disease

• lipid disorders

• arterial disease

skin changes

• localized redness (with light or dark coloration)

• atrophied blanche

• corona phlebectatica (cluster of veins and skin changes)

• lipodermatosclerosis (hardening of skin)

• ulcerated wounds

treatment for superficial venous disease

• stripping and ligation

• endovenous thermal ablation

• chemical ablation/sclerotheraphy

• phlebectomy (micro incision)

stripping and ligation

have been traditional treatment

• associated with “neovascularization”; reappearance of varicose veins

endovenous thermal ablation

has become more popular choice

• thermal device top is positioned in saphenous veins distal to confluence with deep venous system

• performed with either radio frequency or laser energy

• vein is “closed” from within

• anesthesia is places in saphenous sheath

• treated vein with disappear after 6-9 month and before disapearance, treated vein will appear “thrombosed”

chemical ablation

• foamed or liquid chemical (osmotic, detergent, or corrosive agent) is injected directly into the vein

• effective treatment for small or tortuous veins

• often used as a complement of thermal ablation

reverse trendelenburg

deep veins are evaluated initially using — position

standing

CVI evaluation should then be performed with the patient —

• — allows for optimal dilation and venous filling

outward

GSV is examined with patient’s knee rotated —

back

SSV is examined with the patient’s — facing the sonographer

3.5-7.5 MHz

transducer can be used for deeper segments

7.5-17 MHz

transducers are optimal for superficial imaging

acute deep vein thrombosis (DVT)

if — is identified, CVI examination is discontinued and patient is referred for treatment

chronic DVT

is part of CVI examination

• suspected in patients with history of DVT

superficial thrombosis

does not deter evaluation of CVI

• — should be noted and may be treated in thrombus close to deep system junction

compression

— maneuvers are used to elicit reflux

• recommended to use automatic cuff system to perform compressions

70 to 80 mm

compression cuff should quickly inflate to approximately — Hg, hold for a few seconds, then quickly deflate

normal response to proximal compression

• cuff or other technique (i.e., valsalva maneuver) is used to compress veins — to segment being evaluated

• flow should stop during compresssion and resume upon release of compression

normal response to distal compression

• cuff or other technique is used to compress veins proximal— to segment being evaluated

• flow should increase during compression (in an antegrade direction) and stop upon release of compression

abnormal responses for proximal compressions

• retrograde flow occurs during compression

• antegrade flow resumes upon release of compression

abnormal responses for distal compression

• increase in antegrade flow during compression

• retrograde flow is noted upon release of compression

reflux duration is dependent on

• vein filling with blood and emptying with compression

• duration of compression

• interval between compressions

  • should wait at least 30 s between testing sites

reflux duration

(time measurement) should be performed with spectral doppler with vein in longitudinal image

parana maneuver

force patient to shift weight slightly

hand compression

less reproducible but allows more testing variability

valsalva maneuver

laughing, coughing, or talking may be alternatives

protocol for CVI should include

• proper documentation of any anomaly in femoropopliteal segments

• single documentation of saphenous or non saphenous abnormality

3 common test objectives for CVVI

• selection of patients for thermal ablation

• examination of patients of a phlebology clinic with perioperrative capabilities

• examination of patients for limited or extensive stripping/ligation/phlebectomy

special considerations during foam sclerotherapy

• visualize foam in the vein

• transthoracic echo can be used to observe foam arrival in right heart

• transcranial doppler (TCD) may demonstrate emboli in middle cerebral artery (MCA) (also indicate PFO)

alternative explanations to retrograde flow

• where tributaries enter main saphenous

• valve leakage (valves take too long to close or do not remain closed)

• surgical correction to preserve drainage

normal b-mode:

smooth, thin-walled, fully compressible veins with no obvious change in venous diameter

acute DVT:

enlarged, incompressible veins with hypoechoic and/or hyperechoic material in lumen

chronic post-thrombotic changes:

small, retracted vein; partially or completely incompressible with hyperechoic material in lumen

b-mode ultrasound findings of chronic venous valvular insufficiency

• enlarged vein diameter

• vein remains completely compressible

• lumen is hypoechoic

• may see valve sinus with flapping valve leaflets

• tortuous veins

b-mode ultrasound findings after ablation

• immediately, vein still compressed by tuescence

• over 6 to 9 months

  • segmentally sonographically absent

  • fibrosis or thrombosis is visualized

  • recanalization may occur

normal spectral waveform

spontaneous, phasic with respiration unidirectional flow toward heart

• flow augments with distal compression or release of proximal compression

acute DVT spectral waveform

no flow if occlusive; lack of flow augmentation with distal compression or release of proximal compression

partial obstruction

acute or chronic or external compression can cause continuous flow

chronic post-thrombotic changes spectral waveform

small, tortuous channels within disease vein segment; flow in collateral veins

CVI spectral waveform

• reverse flow (reflux) noted following proximal compression or release of distal compression

• turbulent flow may be present in enlarged valve sinuses

DVT color flow

no flow if completely occlusive; flow around thrombus if not occlusive

color flow with CVI

retrograde flow can be visualized but is not quantitative

measurement of reflux duration

preferred over measurement of peak reverse flow velocity or volume flow rate

normal valve closure times for saphenous veins

less than 500 ms

normal valve closure ties for femoropopliteal veins

less than 1 s

normal valve closure times for perforating veins

less than 350 ms

duration of reflux depends on

• vein diameter

• venous blood volume distally

• strength

• duration of distal compression

• characteristics of distal venous network

PPG

emits infrared light and detects signal reflected back from cutaneous vessels

compression/decompression

maneuvers performed and later the amount of blood detected

• amount is reduced when blood is pumped back to heart

• upon completion of maneuvers, blood volume returns to baseline

medial

PPG placed against skin in the — aspect of calf

• can also be placed on posterior calf for evaluation of SSV

5-10 times

calf is emptied by halving the patient perform foot flexion/relaxation about —

PPG tracing

• tracing is flatline at top of strip paper at baseline

• tracing falls to bottom of strip paper with maneuvers

• tracing returns to baseline position during recovery relaxation

25 mm/s

strip paper recording speed is usually —

absence of reflux

timing of blood return is measured and indicated presence or —

venous recovery time (VRT)

is measured from end of flexion/relaxation period to about 95% of the distance between the bottom curve and the baseline tracing

20 s

recovery time is normally greater than — for VRT

10 s

reflux is suspected with refill times less than 20 s; severe reflux is suggested if recovery time is less than —

air plethysmography (APG)

can be used to detect physiologic abnormalities to differentiate between pathophysiologic condition and aesthetic problem

• recommended technique for quantification of chronic venous insufficiency

technique and required documentation for APG

• patient starts from supine to standing positions

• sensing cuff is wrapped around calf; inflated to 10 mm Hg

• leg is elevated to empty venous volume

• leg is brought back to horizontal; cuff is readjusted and calibrated

• patient stands with weight on non-tested leg

while on nontested leg, tested leg maneuvers

• relaxed

• one toe raise

• 10 toe raises

blood venous volume

measurements of APG

• (VV; in mL)

• accumulated when patient moves from supine to standing

filling time (FT)

measurements of APG

• how long to accumulate blood in calf to 90% of VV

volumetric filling rate (FR)

measurements of APG

• blood accumulated per unit time

residual volume (RV)

measurements of APG

• percentage of venous volume; indicates how much volume is pumped from calf after 10 toe raises

APG can also measure

• ejection fraction

• total blood volume accumulated in calf with thigh cuff compression

• volumetric emptying rate (after thigh cuff deflation)

• use of tourniquet to differentiate between deep and superficial reflux

VV normal

vary and depend on gender, age, and other characteristics

normal FT

longer than 25 s

normal FR

less than 2 mL/s

normal RV

less than 20%-35%