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Lower Extremity Ultrasound: Diagnostic and Therapeutic Applications
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33
range of velocity values at the same time, and has more
general applications to arterial imaging. A larger sample
volume within the vein is recommended to detect flow
with a decentralized velocity profile. As is the case for
color flow, Doppler gain settings and velocity scale affect
the sensitivity to flow, or reflux detection. Increased gain
and decreased velocity scale improve detection of low
velocity, low volume reflux. The gain adjustment will be
increased or decreased to provide bright flow velocity
waveforms just below the level that causes a noisy speckle
on the display.
The ultrasound imaging transducer, or probe, one
selects will decide the depth range that can be examined.
Higher frequency transducers, i.e. ranging 10.0–17.0 MHz,
are designed to look in the near field for structures
such as the superficial venous anatomy and/or facilitate
needle access or guidance. Lower frequency transducers,
i.e. ranging 4.5–7.5 MHz, permit visualization at lower
depths and are selected when evaluating the deep veins.
In most instances, when performing a diagnostic study
you will need both a low and a high frequency transducer.
For extremity venous applications, linear transducers
are ideal.
Ultrasound equipment is designed for a variety of
applications, thus manufacturers build in features to
create simple steps to assist users. One helpful feature is
a pre-set function of preferred settings for examination
types, very similar to a short-cut button on a personal
computer. Using these pre-sets as a starting point to begin
the study may help eliminate some of the mystery a new
user may have with ultrasound setups. These presets are
only a suggestion and can be manipulated by the user
anytime during the examination. The settings utilized will
influence results, so familiarity with each setting’s impact
on the image is crucial. These settings include depth,
overall gain, time gain control (TGC), scale, and wall
filters, to name a few. The presets utilized for a diagnostic
study are unique in comparison to those selected for
therapeutic applications. For example, during a diagnostic
survey the dynamic range is set high to discover complexities of tissue and structures. During therapeutic
interventions, decreasing the dynamic range will enable
detection of high contrast objects, such as needles and
catheters.
A variety of factors will influence which ultrasound
instrumentation to purchase. Some of these considerations are intended use, cost, portability, flexibility, and
ergonomics. Of greatest importance to this decision is
consideration of diagnostic quality and the ease with
which results can be obtained.
ULTRASOUND TRAINING
The use of ultrasound technology has become a routine
tool within the specialty of phlebology. The expertise and
training necessary for individuals who utilize ultrasound
will vary. The American College of Phlebology (ACP)
offers ultrasound fellowship training opportunities specific
to venous applications. Other training may include rotational fellowships and regional ultrasound courses. Study
and practice are necessary to obtain experience and confidence in one’s ability.
Professional medical societies such as the American
College of Radiology (ACR) recommend that ‘physicians
responsible for diagnostic ultrasound examinations be able
to demonstrate familiarity with the anatomy, physiology,
and pathophysiology of those organs or anatomic areas
that are being examined’. Though the intent may be to
examine only the venous structures, these are not the only
anatomical features seen on routine examination. Imaging
from the skin line will demonstrate subcutaneous fat,
muscle, tendons, arteries, nerves, joint spaces, periarticular bursae, and bone.
The American College of Surgeons (ACS) suggests
that ‘physicians performing ultrasound examinations and
ultrasound-guided procedures must be familiar with
the principles of ultrasound physics, and the indications,
advantages, limitations, performance, and interpretation
of the ultrasound examinations. Further criteria of personnel performing ultrasound under the supervision of the
surgeon must be appropriately trained and certified and
their performance regularly evaluated within the framework of the quality improvement process.’
Ultrasound credentialing can be obtained through independent bodies such as Cardiovascular Credentialing
International (www.cci-online.org) or the American Reg-
istry of Diagnostic Medical Sonographers (www.ardms.
org). Certification examinations are strongly encouraged
for individuals performing diagnostic ultrasound. The
examination of RPhS (Registered Phlebology Sonographer) is directly linked to individuals performing phlebology ultrasound and would be a worthwhile achievement.
Government and State regulations exist regarding not
only the individuals performing diagnostic ultrasound but
also the accreditation of the ultrasound facility. Many
private insurers also restrict reimbursement for ultrasound
usage based on a variety of factors. Overall these variable
policies may impact the use of ultrasound within an office
or medical setting.
DIAGNOSTIC APPLICATIONS
• Patient assessment
Diagnostic considerations for patients who present with
chronic venous disease will vary, since much depends on
the clinical circumstances. Within previous chapters, great
detail has been given about how to assess a patient with
venous complaints. A summary of the patient’s medical,
surgical and familial history is essential. Not to be overlooked is a simple question regarding the presence of birth
marks. For example, port wine stains may initiate a multifaceted study in search of a vascular malformation diagnosis. Though the diagnostic complexity may fluctuate, a
standard written protocol is imperative. The aim of the
diagnostic study is to determine the function and status
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Treatment of Leg Veins
of the deep and superficial venous structures. Since this
information may likely be the basis on which treatment
is planned, an accurate description of any anatomical and
phy siological abnormality will be essential. Without this,
the method of treatment considered necessary to improve
the patient’s condition will be unclear. Patients also frequently request a copy of their medical records, and a
thorough ultrasound report with documented hard copy
findings will facilitate care elsewhere should the patient
make this decision.
Traditionally, patients who are referred for a diagnostic
ultrasound study are symptomatic, and the investigation
will relate to the symptomatology described. For instance,
unilateral edema will have a unique diagnostic aim compared to a patient with bilateral edema. If the patient
presents with cosmetic concerns (such as ‘matting’ or new
telangiectasias) and has failed sclerotherapy, the basis for
examination is to identify an explanation for the surge of
new vessel occurrence. Patients may present with the
mildest form of skin changes (telangiectasias) to the most
severe (ulceration). The primary aim of the diagnostic
study should be to identify the pathologic phenomenon
contributing to the patient’s disease. The role of the diagnostic study in the evaluation of patients presenting with
symptomatic chronic venous disease would be to identify
a reason commensurate with the patient’s complaints and/
or to provide a basis for the distribution of varicose veins
clinically manifested. Patients presenting with atypical
diagnostic complexities may be better served if evaluated
by a more experienced sonologist.
• Diagnostic duplex evaluation
The diagnostic assessment is of utmost importance for
good clinical outcomes. It must not be rushed, as a meticulous description of the anatomic and physiologic findings
will be an essential aid in the patient’s course of
treatment.
Proper diagnosis and identification of key anatomic
elements will impact treatment planning of the great or
small saphenous veins or tributaries of the superficial
veins. Variations exist within the venous system, thus the
sonologist must have a thorough and accurate knowledge
of both deep and superficial venous anatomy and pathophysiology, as described within previous chapters of this text.
Consensus documents from the Union of International
Phlebology (UIP) detailing the ultrasound anatomy and
the principles of ultrasound diagnosis were published
in 2006 (Cavezzi et al 2006, Coleridege-Smith et al 2006).
These documents are an excellent resource and are recommended by this author for further reading and study.
it is apparent that all the compartments are intimately
interconnected, and it is impossible to segregate one
without consideration of the other two. All three compartments of the venous system are suspended between
the balances of flow determined by pressure gradients. A
reflux examination will evaluate all three compartments,
and the total of all findings should explain the patient’s
clinical presentation and equal the sum of ultrasound conclusion.
Venous flow between the compartments is synchronized by a series of one-way valves intended to open and
close, facilitating drainage towards the heart. Described as
the hierarchy of drainage, blood flows from the microcirculation to superficial tributaries to saphenous to the deep
venous system or from the superficial veins to the deep
system via perforating veins. Duplex ultrasound examination of the venous system to study reflux is a search for
any flow abnormality between the compartments, both
at their beginning and at their end. Abnormal flow is the
detection of flow disrupting the drainage hierarchy.
The study aim of venous valvular function is to identify
reflux, defined essentially as retrograde flow for an abnormal duration of time. Venous valvular reflux can be
observed using spectral Doppler and/or color flow, relying
on various maneuvers to study flow in provoked response
to valve closure/function (see Box 4.1). These methods
impose force to generate a pressure gradient that will
stimulate normal one-way valves to close. Valves failing to
close permit abnormal retrograde flow (reflux). The duration of retrograde flow considered to be abnormal has
been studied. According to noted author and scientist, Dr.
Nicos Labropoulos, unique reflux values are applied to
deep, superficial, and perforating veins (see Table 4.1).
Though reflux values as an absolute time have been
described, keep in mind the reported research values were
obtained by experienced users. Artifact can occur at the
site of reflux evaluation, particularly if obtained by less
experienced users or if the calculation of valve closure
timing is incorrect. A conservative reflux time measure, in
the author’s opinion, is 1.5 second of retrograde flow in
the deep system and 1.0 second of retrograde flow in the
superficial system. New research and understanding of
reflux values in perforating veins is evolving. As one studies
flow in the perforating veins, retrograde (outward) flow
Table 4.1 Duration of abnormal reflux time according
to Nicos Labropoulos, PhD
GSV SSV Perforators
Femoral
vein
Popliteal
vein
• Reflux studies
The identification of venous valvular reflux (i.e. retrograde
flow) is actually a composite of information. The veins in
the lower extremity are divided into three compartments
and are comprised of the deep, saphenous and superficial
veins. As one begins to examine one vein or compartment,
>0.5 sec >0.5 sec >0.35 sec >1.0 sec >1.0 sec
Reflux duration of flow observed during diastole is quantified
as abnormal based on the established values noted above.
Though reflux time values are important, the study values
obtained are influenced by the vein diameter and the venous
reservoir capacity.
Box 4.1 Commentary on reflux maneuvers
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Methods Utilized to Elicit Valve Closure to Observe Reflux
The transducer is held to the skin over the vessel of interest
v
Valsalva maneuver: movement of blood occurs with
inspiration and cessation of moving blood with forced
contraction. Retrograde flow observed during forced
contraction is positive.
v
Compression of distal veins: movement of blood occurs
with augmentation of the tissue distal to the transducer
and cessation of blood movement upon augmentation
release. Retrograde flow observed during release is
positive.
v
Use of rapid cuff inflation/deflation device: a standardized
cuff is positioned onto the thigh or calf approximately
5 cm. below the ultrasound transducer. With rapid cuff
inflation forward movement of blood is observed. With
rapid deflation cessation of blood movement is observed.
Retrograde movement of blood observed with deflation is
positive.
v
Parana maneuver (modified): movement of blood is
provoked with the patient’s muscular contraction and
relaxation. The patient swaying slightly forward
(contraction) enhances blood movement (systole). As the
patient balances back during relaxation (diastole), blood
movement ceases. Observation of retrograde blood
movement during relaxation is positive for reflux.
may be discovered and conservatively measured at 0.5
seconds. Vein diameter and the venous reservoir capacity
influence reflux duration as well, and relationships have
been described between vein diameter and reflux.
The amount of reflux necessary to produce clinical
symptoms is yet to be established. However, patients with
reflux consistently describe complaints similarly, including
pain, aching, fatigue, heaviness, swelling, itching, or spontaneous venous rupture. Asymptomatic patients with large
varicose veins are not uncommon.
Reflux studies are an ultrasound observation of venous
blood flow movement within the vessel and from one
compartment to the next, or movement towards the
heart. Prior to inspection for ‘abnormal’ retrograde flow,
or reflux, an understanding of ‘normal’ antegrade flow is
fundamental. Otherwise, the significance of retrograde
flow identified may be overvalued or misunderstood.
Reading earlier chapters will explain the pathophysiologic
role of the superficial, perforating, and deep veins. In
earlier text, the hierarchy of venous drainage was
described. In patients presenting with advancing stages of
varicose veins, the blood is no longer sufficiently drained
because there is a discrepancy between reflux volume and
drainage volume. A reflux examination is an attempt to
replicate or mimic dynamic blood flow. Gravity plays a
role in the study of venous valvular dynamics, thus a
standardized duplex study for reflux is obtained while the
patient is standing. Other variables of reflux detection
may include time of day, temperature, hormonal influences, and proximal obstruction.
Before beginning the study of ultrasound venous valvular function with duplex, first obtain an anatomic survey
to visualize the venous system from the deepest to the
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Lower Extremity Ultrasound: Diagnostic and Therapeutic Applications
Figure 4.2 Transverse gray scale ultrasound image of a normal
common femoral artery and common femoral vein
most superficial. Too frequently the studies are performed
in opposite fashion, without attention to what is of fundamental importance.
• Examination of the deep venous system
The historical application of duplex ultrasound has been
targeted at the deep venous system, and there are numerous resources and publications available detailing the deep
venous examination. Further reading should include published standards by the Society of Vascular Ultrasound
(SVU) or the Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL). Appropriate flowsensitive ultrasound instrumentation and transducers are
necessary to achieve accurate results.
As emphasized above, the study of the three compartments will begin with the deep venous system, an essential
step prior to evaluating the saphenous and superficial
venous system. The principle of deep venous diagnosis
relies on three methods: compression, color flow, and
spectral Doppler. The following text explains a focused
protocol for a patient presenting with symptomatic varicose veins without suspicion for vascular malformation,
pelvic insufficiency, or deep venous obstruction. Though
a normal study is anticipated in most patients presenting
with primary varicose veins, the sonologist must be skilled
at detecting abnormal ultrasound findings. The individual
patient’s clinical presentation and/or consequent abnormal ultrasound findings may determine if a deviation from
a standard protocol is warranted.
The study of the deep venous system is best performed
with the patient supine, and with the hip rotated slightly
outward. Begin with an anatomic survey in cross-sectional
imaging with a transverse orientation of the transducer
(described as the transducer rotated 90°). Identify the
common femoral vein (CFV) at the level of the groin
crease. Immediately adjacent to the CFV is the common
femoral artery (CFA) (Fig. 4.2). The arterial structures are
an important deep venous ultrasound landmark for the
examiner. The two vessels should be relatively equal in
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Treatment of Leg Veins
caliber and echogenicity. Marked vessel disparity may
suggest aneurysmal dilatation, and the relevance of this
finding will correspondingly have significance to either
vessel. Additionally, identify the presence of any echogenic foci either within the vein (Fig. 4.3A,B) or the artery
(Fig. 4.4A,B). Echogenicity within the vessel lumen are
considered abnormal findings either as thrombus (venous)
or atherosclerosis (arterial). With the patient relaxed,
compression with the transducer at the skin’s surface
should achieve complete coaption of the vein walls (Fig.
4.5). The arterial structures do not collapse. The compres-
sion study is a careful full-length survey of the deep
venous system and includes the common femoral (CFV),
femoral (FV), deep femoral (DFV), popliteal (POP), posterior tibial (PTV), anterior tibial (ATV) and peroneal
veins (PERO). This portion of the study should not be
rushed, as there are variations to the anatomy. Compression and coaption of the veins is the mainstay of excluding
deep vein thrombosis. Areas of venous noncompressibility
suggest thrombosis within the lumen.
Duplications within the deep venous system are fre-
quent, including the femoral and popliteal (Fig. 4.6A,B).
Duplications, in a strict anatomic definition, occur when
two veins share the same path. The duplication will demonstrate a beginning and end along the same path. The
significance of these duplications includes possible missed
deep vein thrombosis (DVT) on examination. Additionally, because of diameter disparities, duplications may be
important to note when applying foam sclerotherapy
treatment (see additional text in Therapeutic applications
section).
Once the gray-scale anatomic survey of the deep
venous compartment is completed and documented, the
physiologic study is obtained using Doppler devices.
Doppler spectral venous flow patterns which are phasic
and spontaneous are normal characteristics. With deep
inspiration, the spectral display will cease as a result of
the diaphragmatic compression on the inferior vena cava
(Fig. 4.7). Frequently, venous pulsatility may be observed
and can be considered a normal finding in well-hydrated
healthy individuals (Fig. 4.8). Venous pulsatility can also
be related to elevated right heart pressure in pathological
entities such as tricuspid insufficiency, right-sided heart
failure, and severe pulmonary disease. Clinical correlation
A B
A B
Figure 4.3 (A) Longitudinal gray scale
ultrasound image of an abnormal
common femoral vein with evidence for
mixed echogenicity within the lumen
indicative of chronic deep vein
thrombosis. (B) Longitudinal color flow
ultrasound image of an abnormal common
femoral vein with evidence for poor color
filling of the lumen indicative of chronic
deep vein thrombosis
Figure 4.4 (A) Transverse gray scale
ultrasound image of the CFA and CFV.
Note the brightly echogenic foci within the
CFA depicting calcified atherosclerotic
plaque. (B) Longitudinal gray scale
ultrasound image of the common femoral
artery with evidence of brightly echogenic
foci (atherosclerotic plaque) on the deep
wall of the vessel
Lower Extremity Ultrasound: Diagnostic and Therapeutic Applications
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Figure 4.5 Dual screen transverse gray
scale ultrasound image with side-by-side
comparison of transducer compression
(right image) versus non-compression
(left image)
37
A B
Figure 4.7 Color flow ultrasound image with phasic venous spectra in
the common femoral vein. Cessation of spectral flow is observed with
deep inspiration
Figure 4.6 (A) Transverse gray scale
ultrasound image of duplicated femoral
veins of the thigh and superficial femoral
artery. The duplicated veins are marked
by calipers. (B) Longitudinal color flow
ultrasound image of duplicated femoral
veins of the thigh
Figure 4.8 Color flow ultrasound image with venous spectral display
of pulsatility in the common femoral vein
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A B
Figure 4.9 Color flow ultrasound image with disparate comparison venous spectra observed in the right and left common femoral vein
will be useful when pulsatility is encountered. In addition,
ultrasound artifacts may mimic venous pulsatility as a
consequence of tissue vibration from the normal corresponding artery. The spectral waveform of the CFV is
most revealing, particularly if there is a disparity of flow
on the contralateral limb (Fig. 4.9A,B). Abnormal flow
properties in the CFV suggest proximal disease, and additional diagnostic work-up may be initiated if clinically
indicated. As noted previously, venous valvular incompetence can be studied with various maneuvers. A Valsalva
maneuver is preferred for the CFV. Deep venous valvular
insufficiency (reflux), in the author’s opinion, is conservatively categorized as retrograde flow greater than 1.5
seconds, though this measurement can be over-estimated
if there is ambiguity of when valve closure begins. If reflux
is detected, consider reproducing the finding to confirm
the results. The protocol for a screening study includes
spectral waveforms of the CFV and POP veins. Additional
deep veins can be studied in a similar manner, and may
vary with laboratory protocols. The significance of reflux
within the deep venous compartment may be a function
of abnormal flow relative to drainage to and from other
compartments. Color flow is useful to document patency
of the deep vessels examined. Once completed, proceed
with assessment of the superficial compartment and perforating veins.
• Examination of the superficial
venous system
Recent adopted nomenclature changes do apply specifically to the superficial system and include the great saphenous vein (GSV), formerly greater or long saphenous, and
the small saphenous (SSV), formerly lesser or short saphe-
nous. Further descriptions of the saphenous nomenclature
include veins according to their anatomical position, and
include the anterior accessory saphenous vein (AASV) and
posterior accessory saphenous vein (PASV). Other veins
examined may not be formally named, and variations exist
from patient to patient. The saphenous fascial layer serves
as the ultrasound landmark for accurate identification of
saphenous veins examined (Fig. 4.10A,B). Ultrasound recognition of this feature, termed the ‘saphenous eye’, is
paramount in the examination of the saphenous veins and
the superficial compartment. Although the proximal
AASV will be surrounded by a fascial layer, the underlying
deep venous system serves as a corresponding ultrasound
landmark. During a cross sectional anatomical survey of
the proximal GSV, two ‘saphenous’ veins noted in fascia
may be a source of confusion as to mimic a duplication of
the GSV. At this level, ultrasound identification of the
deep venous system inferior to the vein will differentiate
the AASV from the GSV. Termed the ‘alignment sign’,
the AASV is aligned with the deep vascular system (Fig.
4.11). The AASV typically courses in the thigh anterior
and lateral while the GSV courses medially. The PASV
courses posterior and will serve as a connection from the
Giacomini vein, when present. Veins that pierce the
saphenous fascial boundary to the superficial layer are
termed tributaries based on their anatomical location and
distribution (Fig. 4.12). Tributaries are commonly a source
of reflux and may be of primary significance in certain
patients. Ultrasound identification of the GSV below the
knee is aided by what is termed the ‘angle sign’ (Fig. 4.13).
Cross-sectional imaging displays the GSV (within the
saphenous compartment) anteromedial to the tibia and
anterolateral to the gastrocnemius muscle. Ultrasound
identification of this triangular form will aid the user in
Lower Extremity Ultrasound: Diagnostic and Therapeutic Applications
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39
BA
Figure 4.11 Transverse gray scale ultrasound image of the
‘alignment’ sign depicting the GSV and AASV. The AASV is aligned
with the deep vascular anatomy and the GSV is medial to deep
structures
Figure 4.12 Transverse gray scale ultrasound image of GSV within
fascia (small diameter) and a tributary (larger diameter) within the
superficial fascia. The vessel disparity may be an important discovery
during an ultrasound examination
Figure 4.10 Transverse gray scale
ultrasound image of the ‘eye’ of the great
(A) and small (B) saphenous veins
Figure 4.13 Transverse gray scale ultrasound image of the GSV and
the ‘angle sign’. The triangular form includes the GSV within the
saphenous eye, the gastrocnemius muscle, and the tibia
recognition of other structures including bone and muscle.
Duplications of the GSV and SSV are described. As a
reminder from previous text, the duplicated veins must
follow within the same path and remain within the fascia
parallel. With this strict definition, duplications of the
GSV and SSV are not as common.
The GSV and SSV normally will terminate into the
deep venous system. Known as the saphenofemoral junction (SFJ), the GSV terminates at the CFV. The SSV
deep vein termination varies and includes the popliteal
vein at the saphenopopliteal junction (SPJ), the gastrocnemius vein, and the distal femoral vein of the thigh. In
some instances, no deep vein connection is established,
and the SSV extends proximal in the thigh into the thigh
extension of the SSV or Giacomini vein. Given these
anatomic variations, the SSV investigation can be more
challenging.
Venous valvular structures are readily visible with high
resolution duplex. Fascinating to observe, the bicuspid
valve leaflets point to the direction of drainage (Fig. 4.14).
With B-mode imaging, increasing the dynamic range and
overall gain settings will facilitate observation of the valve
leaflets and blood flow dynamics within the vein lumen.
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Figure 4.14 Longitudinal gray scale ultrasound image of the GSV
with identification of venous valvular leaflets. Note the leaflets point to
the direction of normal drainage
Color flow is commonly utilized with the color blue
selected to represent flow towards the heart and the color
red to denote flow away from the heart. With muscular
contraction (venous systole), venous valves open. With
muscular relaxation (venous diastole), proximal venous
valves close. The series of synchronized valves act to regulate flow of blood return from the superficial and perforating veins to the deep system and eventually to the
heart. Thus incompetent valves result in retrograde flow,
or reflux. Duplex examination of the superficial compartment segmentally investigates the competence of valves
along the course of the veins. The study is dynamic, and
with practice, the sonologist will gain recognition of
normal and abnormal findings.
Anatomical variations can create distractions from a
focused protocol when examining the saphenous veins.
Multiple veins coursing in numerous directions in and out
of fascia, with or without reflux, describe a simplistic
explanation of what one may encounter. Keeping in mind
the patient’s clinical picture, perform the study in an
orderly manner, and look for patterns of reflux to establish
a diagnosis. Reflux patterns in the saphenous veins
have been described by Dr. Olivier Pichot as either (1)
terminal valve; (2) pre-terminal valve; (3) segmental;
(4) multiple source; (5) atypical; or (6) recurrence after
stripping. Given these specific parameters, categorizing
the patient’s finding to one of these patterns may lessen
the tedious process of saphenous reflux examinations. The
ultrasound anatomic descriptions above should assist in
recognition of the saphenous veins and important superficial tributaries.
Also recommended by the Author is the reading of
published works by Dr. Paolo Zamboni and Dr. Claude
Franceschi. Their classifications of venous shunts and
‘escape points’ apply venous hemodynamic theories to
specific surgical interventions. Specifically, venous pathways are numbered in the following manner: deep veins
N1, saphenous veins N2, tributary or superficial veins N3,
connecting veins N4, and the microcirculation as N5. The
Figure 4.15 Example of platform device for an erect study of the
superficial venous system. The railings and step are ideal to steady
the patient and apply useful ergonomics for the sonologist
venous pathways of reflux and drainage are numerically
chosen to describe the abnormality as an escape point
(shunt) and the re-entry to the deep system (via perforating veins). For example, N2-N3-N1 would represent
reflux in the saphenous vein (N2), to a superficial tributary vein (N3) and drainage to the deep system (N1) via
perforating veins (re-entry). This method is favored by the
Author, though greater recognition of this numerical classification is necessary for universal understanding. Adoption of duplex classifications may be necessary to critically
evaluate treatment methods and outcomes.
The superficial venous system evaluation is completed
with the patient in an erect position. This method is the
accepted standard and will impose gravitational force on
the venous system. Many advocate the use of a platform
device to maximize comfort and provide essential ergonomics for the examiner. In the author’s center, a carpenter was contracted to build a step device (Fig. 4.15).
Railings are useful to steady patients, particularly if they
develop vasovagal symptoms (common) during the examination. Begin the study of the GSV with the patient
facing the examiner, with the extremity of interest rotated
outward. This extremity should be relaxed with the
patient’s weight counterbalanced by the opposite extremity. Begin with an anatomic survey in cross-sectional
imaging with a transverse orientation of the transducer.
Identify the GSV as it terminates into the CFV. Continue
moving distal from the SFJ to visually inspect other veins
within the fascia (AASV or PASV) as described above.
The GSV courses medial, and completion of the full
length anatomic survey will identify tributaries, which are
Figure 4.16 Longitudinal gray scale ultrasound image of the GSV
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with identification of the terminal and pre-terminal valve leaflets at the
saphenofemoral junction
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Lower Extremity Ultrasound: Diagnostic and Therapeutic Applications
veins that pierce the superficial fascial layer toward the
skin. Other veins that pierce the deep fascia are perforating veins and will be described later in this chapter. The
GSV may also pierce the fascia moving in and out of the
saphenous compartment. In some patients, the GSV is
hypoplastic or aplastic. The anatomic survey will familiarize the sonologist as to the pattern of venous distribution/
location, changes in fascial location, and vein caliber
increases or decreases. Large fluctuations in diameter will
alert the examiner to volume changes that will suggest
reflux patterns. As one becomes a trained observer, ultrasound recognition of the GSV and important tributaries
will become second nature. Documentation of transverse
diameter measurements is based on individual protocol,
though it is a standard to document increased diameter.
Of importance are veins that demonstrate increased relative diameter and include the GSV and SSV at their
respective junctions and large tributary veins. Once the
anatomy and distribution of the saphenous veins and tributaries are known, a Doppler flow survey is performed.
In a transverse orientation of the transducer at the SFJ,
rotation of the transducer 90° will permit longitudinal
visualization of the terminal valve and pre-terminal valve
(Fig. 4.16). Terminal valve competence can first be studied
by observation with color flow. When the patient performs a Valsalva maneuver, color flow should be absent in
the GSV, indicating valve competence during diastole.
Retrograde flow observed with provoked maneuvers may
suggest reflux (Fig. 4.17), and Doppler spectral interrogation is obtained proximal to the valve leaflets. Doppler
spectral waveforms obtained at this level with retrograde
flow (during diastole) greater than 1 second is diagnostic
of terminal valve incompetence (Fig. 4.18). If terminal
valve incompetence is detected, the remainder of the
saphenous survey will determine the length of reflux and
the location of the blood column’s re-entry to the deep
venous system via perforating veins. In the presence of a
competent terminal valve, the pre-terminal valve is examined with the method described for the terminal valve.
Doppler spectral waveforms depicting retrograde flow
measured as greater than 1 second obtained at this level
Figure 4.17 Longitudinal color flow ultrasound image of terminal
valve incompetence captured during Valsalva maneuvers in diastole
venous phase
Figure 4.18 Venous spectra of the great saphenous vein terminal
valve with retrograde diastolic flow greater than 1.0 second
is diagnostic of pre-terminal valve reflux (Fig. 4.19A,B).
Further examination of saphenous tributaries that drain
between the terminal and pre-terminal valve (superficial
circumflex iliac, superficial epigastric, or superficial external pudendal) may reveal the reflux source. The anterior
accessory saphenous vein may also be a source of reflux.
Continue a segmental evaluation of the GSV to the ankle,
with focused attention of flow deviation segmentally (Fig.
4.20A,B), to any tributaries or through perforating veins
(Fig. 4.21A,B). In lieu of Valsalva, other maneuvers may
be more effective in the distal extremity to provoke valve
closure. Simply squeezing tissue proximal or distal to the
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Treatment of Leg Veins
A B
Figure 4.19 Duplex ultrasound image of
BA
pre-terminal valvular incompetence with
color flow (A) and spectra (B)
Figure 4.20 (A) Longitudinal color flow
image depicting retrograde flow segmentally
during diastolic venous flow with retrograde
color flow present at a valve leaflet.
The remainder of the venous segment
proximally is competent. (B) Spectral
analysis of the GSV
A B
vessel interrogation site can potentially elicit reflux,
though this method introduces significant variability to the
study based on the investigator’s hand size and grip
strength. To stimulate valve closure, flow velocities must
exceed a value of 30 cm/s. To increase sensitivity of valvular function, maneuvers favored by the author include
the use of a rapid cuff inflation/deflation (RCI) device or
the Parana maneuver. A footswitch controls a RCI device
to rapidly inflate and deflate a cuff positioned below the
interrogation site (according to laboratory protocols)
while Doppler is simultaneously observed by the examiner. The Parana maneuver uses the patient’s own muscular contractions to enhance blood movement. This
maneuver is performed with the extremity of interest
slightly forward and relaxed, toes pointed outward, with
the patient’s weight counterbalanced by the opposite
extremity. The examiner instructs the patient to gently
rock forward (systole) onto the ball of the foot and then
back to the starting position (diastole). The examiner
Figure 4.21 (A) Longitudinal gray scale
image of a perforating vein and (B) venous
spectra of an incompetent perforating vein
with bidirectional spectral flow
steadies the transducer in place to observe Doppler flow.
This method requires some skill to maintain transducer
placement on the skin during movement, but overall the
method is reliable with practice.
Begin the study of the SSV with the patient turned
away from the examiner. The extremity of interest should
be relaxed with the patient’s weight counterbalanced by
the opposite extremity. As described previously, the termination of the SSV is variable. Begin the anatomic survey
of the SSV in the posterior mid-calf region to identify the
ultrasound landmark of the SSV ‘saphenous eye’. Proceed
proximal towards the popliteal crease to observe the exact
termination of the SSV to the deep system. Extension of
the SSV into the thigh is common, with or without termination into the popliteal vein. In a systematic method,
similar to the GSV, evaluation of the SSV includes an
anatomic survey in cross section from the lateral malleolus
to the SPJ. In the absence of pathology and increased vein
volume, the small caliber of the SSV can be technically
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