Skin & Aging is proud to bring you this latest installment in its CME series. This series consists of regular CME activities that qualify you for one category 1 physician credit hour. As a reader of Skin & Aging, this course is brought to you free of charge — you aren’t required to pay a processing fee.
Lower extremity venous disease symptoms and complications range from asymptomatic clusters of spider veins along the medial ankles, to bulging varicose veins extending across the anterior thigh, to stasis dermatitis, leg edema and chronic ulceration of the lower medial calf. Citing the often disappointing results historically achieved with surgery, authors Girish Munavalli, M.D., M.H.S., and Robert A. Weiss, M.D., first describe the pathophysiology of venous disease of the lower and the skin changes that accompany chronic venous disease, then discuss treatment options for eliminating saphenous reflux using endovenous laser ablation techniques.
At the end of this article, you’ll find an exam. Mark your responses in the designated area, then fax page 70 to NACCME at (610) 560-0501.
We’ll also post this course on our Web site, which you can access at www.skinandaging.com. I hope this CME contributes to your clinical skills.
Amy McMichael, M.D.
CME Editor
Principal Faculty: Girish Munavalli, M.D., M.H.S., and Robert A. Weiss, M.D.
Method of Participation: Physicians may receive one category 1 credit by reading the article on pages 64 through 68 and successfully answering the questions found on page 69. A score of 70% is required for passing. Submit your answers and evaluation via fax; or you may log on to our Web site at www.skinandaging.com.
Estimated Time to Complete Activity: 1 hour
Date of Original Release: June 1, 2007
Expiration Date: May 31, 2008
Accreditation Statement: This activity is sponsored by the North American Center for Continuing Medical Education (NACCME). NACCME is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. NACCME designates this educational activity for a maximum of 1 AMA PRA Category 1 Credit.™ Physicians should only claim credit commensurate with the extent of their participation in the activity. This activity has been planned and produced in accordance with the ACCME Essential Areas and Policies.
Disclosures: All those with control over the content of continuing education programs sponsored by NACCME are expected to disclose to the meeting audience any real or apparent conflicts of interest related to the content of their presentation. It is not assumed that these financial interests or affiliations will have an adverse impact on presentations; they are simply noted here to fully inform participants.
Dr. Munavallli has disclosed that he is a member of the speakers' bureau for Cool Touch Lasers.
Dr. Weiss has disclosed that he is a consultant, scientific advisor and has other financial interests in Cool Touch.
Sponsor: This activity is sponsored by the North American Center for Continuing Medical Education.
Learning Objectives:
1.Briefly describe the pathophysiology of venous disease of the lower extremities from small vessel spider veins to saphenous reflux
2. Describe the skin changes that accompany chronic venous disease
3. Discuss treatment options for eliminating saphenous reflux using endovenous laser ablation techniques
Target Audience: Dermatologists, Plastic Surgeons, Internists
Commercial Support: None
Sponsor: NACCME
Clinical manifestations of lower extremity venous disease encompasses a wide spectrum of manifestations, from an asymptomatic cluster of spider veins along the medial ankles, to bulging varicose veins extending across the anterior thigh, to stasis dermatitis, leg edema and chronic ulceration of the lower medial calf.
Phlebology, the science of treatment of venous disease, has roots dating to the ancient Greeks in 400 B.C, at which time venous disease was viewed as problematic and unsightly.1 Procedures involving the use of instrumentation to traumatize veins were described by Hippocrates in the fourth century B.C., and procedures such as rudimentary vein stripping were routinely practiced.1
Venous Insufficiency
Venous disease still presents a formidable challenge to diagnose and treat. Venous insufficiency, which is caused by valvular incompetence in the deep or superficial venous system, is the most common form of venous disease.2 Venous disease affects 40% to 55% of the population, with common symptoms of leg pain, swelling, and skin changes.3 The most common form of lower extremity venous disease is superficial venous insufficiency.
The two major divisions of the superficial venous system are the greater or great saphenous vein (GSV) and lesser or small saphenous vein (LSV). (See Figure 1.) From an anatomical standpoint, the distinction between the two divisions is simple to make. The GSV distribution is along the medial aspect of the leg from the groin to the ankle, while the LSV distribution is along the middle of the posterior calf, from the popliteal fossa to the lower posterior calf.
Venus Insufficiency Causes
Venous insufficiency is the result of incompetence or reflux in either or both of these truncal veins. Greater than 90% of the time, the GSV is the cause of venous insufficiency. Venous insufficiency occurs when a high-pressure leakage develops between the deep and superficial systems or within the superficial system itself, followed by sequential failure of the venous valves in superficial veins. This allows venous blood to escape from its normal flow path and to flow in a retrograde direction down into an already congested leg. Over time, incompetent truncal veins acquire the typical dilated and tortuous appearance of varicosities.
Associated Skin Changes
Furthermore, insufficiency can lead to chronic morbidity in the form of ulcerative, edematous, and pigmentary skin changes in the lower extremities. One such example of a skin change, which is a direct consequence of venous insufficiency, is stasis dermatitis. (See Figure 2.)
Stasis dermatitis has an estimated prevalence of 6% to 7% in adults over the age of 50. In the United States, this is thought to be between 6 and 7 million people.4 As mentioned, abnormal function of the one-way venous valvular system in the deep and superficial venous systems of the legs results in backflow of blood from the deep venous system and perforating veins to the superficial venous system, with accompanying venous hypertension.
Causes of loss of valvular function include: genetic predisposition, hormonal influences from pregnancy, trauma, and an age-related decrease in valve competency. Other events, such as deep venous thrombosis or prior vein surgery, can severely damage the lower-extremity venous system function and cause valvular incompetence.
The mechanism by which venous hypertension causes skin inflammation and stasis dermatitis has been extensively studied. It is thought that increased venous hydrostatic pressure is transmitted to the dermal microcirculation, leading to increased permeability of dermal capillaries. This increased permeability enables plasma macromolecules, such as fibrinogen, to leak out of the vasculature into the pericapillary tissue; then, polymerization of fibrinogen to fibrin results in the formation of a fibrin cuff around dermal capillaries, further congesting flow.4
Stasis dermatitis frequently occurs along with a background of skin changes typical for venous insufficiency patients. Changes include edema, varicosities, hyperpigmentation, atrophic patches (atrophie blanche), and diffuse red-brown discoloration representing deep dermal deposits of hemosiderin (from degraded, extravasated erythrocytes). Often, these chronic changes persist despite stasis dermatitis activity.5
Complications That Can Occur
The dreaded complication of skin ulceration often occurs with chronic stasis dermatitis and accompanying edema. It is thought that 60% to 70% of lower leg ulcers can be attributed to venous disease. Aside from skin changes, patients also experience other nagging symptoms such as lower leg throbbing, swelling, itching, aching pain and restless leg tendencies.
Preventing Skin Changes
To prevent chronic skin changes from venous reflux as well as avoid the daily occurrence of pain, definitive treatment for venous hypertension should be sought as soon as possible.
Surgical Correction
Historically, methods for surgical correction have included vein stripping, ligation and division, echosclerotherapy, and valve replacement. Vein stripping has a failure rate as high as 60%6,7,8 and requires general or spinal anesthesia. Recovery times can often take 2 to 3 weeks. Similar to vein stripping, the reported incidence rate for GSV reflux following high ligation alone is significant with up to 71% recurrence.6,7 Postulated reasons for this include under-recognized anomalous anatomic vascular patterns in the saphenous systems and neo-vascularization.
Endovenous Laser Treatment
In 2002, the FDA approved endovenous laser treatment as a minimally invasive method of ablating incompetent saphenous veins. This in-office procedure uses local anesthesia, thus eliminating the need for general or spinal anesthesia, and the inherent risks associated with them.
The use of endovenous procedures to eliminate saphenous and primary branch reflux has been growing exponentially over the last few years. In stark contrast to the very invasive nature of stripping and ligation, the concept of obtaining percutaneous access to a vein under local anesthesia and using a form of directed laser energy from the inside to shrink and seal the targeted vein allows for quick patient recovery. (See Figure 3.)
Although initially developed by dermatologic surgeons, the endovenous ablation has been embraced by many other specialties including radiology, vascular surgery and anesthesiology.
It began with the use of a specially and elegantly designed bipolar radiofrequency (RF) catheter for gentle heating and was quickly applied to bare laser fibers fired within the targeted varicose or refluxing saphenous vein.9 With worldwide clinical experience of more than 60,000 procedures since 1999, radiofrequency shrinkage of veins has been a valuable addition to treating large varicose veins resulting from saphenous reflux.
Today there are numerous systems available that utilize various infrared wavelengths as well as radiofrequency to accomplish endoluminal heating and shrinkage of saphenous trunks.
Endovenous Laser Treatment
The following discussion will focus on two classes of laser endovenous treatment: lasers targeting hemoglobin (810 nm, 940 nm and 980 nm) within blood inside the vein, and lasers targeting water in the vein wall (1320 nm).
Utilization of Tumescent Anesthesia
As a prelude to this discussion, it is important to emphasize the role of tumescent anesthesia in reducing side effects following endovenous laser ablation. Dermatologic surgeons, experienced with large-volume, low-concentration tumescent anesthesia for liposuction and other surgical procedures, were the first to apply tumescent infiltration to endovenous techniques.
Tumescent anesthesia or the placement of large volumes of dilute anesthesia in a peri-vascular position, under the direction of duplex guidance, serves several purposes:
- It protects peri-vascular tissues from the thermal effects of intravascular energy by serving as a heat sink.
- It decreases the diameter of the treated vein to allow for better absorption of energy by the target chromophore and thus secondarily reduce intravascular blood for non-specific coagulation.
- It provides more effective and safer anesthesia for patients.
Using tumescent anesthesia, the GSV could be sealed with endovenous techniques as a totally painless procedure with little downtime and immediate ambulation of the patient.
From the authors’ experience with tumescent anesthesia (utilized in every endovenous ablation surgical case), the technique is vital to prevent the formation of deep vein thrombosis (DVT). The incidence of DVT as measured by duplex ultrasound follow-up at 3 to 14 days is 0% (personal communication, R. Weiss, M.D.). It is our firm belief that the use of tumescent anesthesia in non-sedated, conscious patients followed by immediate ambulation at the conclusion of the procedure is the reason for lack of serious adverse sequelae such as DVT.
Targeting Hemoglobin
Endovenous laser treatment allows delivery of laser energy directly into the blood vessel lumen in order to produce endothelial and vein wall damage with subsequent fibrosis. The various lasers available for endovenous are summarized in Table 1.
The presumed target for lasers with 810-nm, 940-nm, and 980-nm wavelengths is intravascular red blood cell absorption of laser energy with dissipation of heat and thrombotic vein occlusion with some intramural heat damage.
Steam bubbles occurring as blood is boiled within the lumen have been shown to occur as the primary mechanism for hemoglobin targeting laser endovenous occlusion effects.10
Direct thermal effects on the vein wall without the presence of blood probably do not occur.11 The extent of thermal injury to tissue depends strongly on the amount and duration of heat the tissue is exposed to, which for these lasers depends on multiple factors including blood in the lumen, rate of pullback and amount of tumescent anesthesia placed around the vein.12
Initial reports have shown this technique with an 810-nm diode laser to have good short-term efficacy in the treatment of the incompetent GSV, with 96% or higher occlusion at 9 months with a less than 1% incidence of transient paresthesia.13,14 More recently, 2-year follow-up of 499 limbs has been completed with a recurrence rate of less than 7% at 2-year follow-up. However, 90% of these patients experienced degrees of post-operative ecchymosis and varying degrees of discomfort.15 Skin burns have been observed by our center and recently have been reported using the 810-nm wavelength.16 DVT extending into the femoral vein recently has also been reported with endovenous laser treatment.17
Post-Treatment Effects
Patients treated with an 810-nm diode laser have shown an increase in post-treatment purpura and tenderness. Most patients do not return to complete functional normality for 2 to 7 days as opposed to the 1 day “down-time” with RF closure of the GSV. Recent studies suggest that pulsed 810-nm diode laser treatment, with its increased risk for perforation of the vein as opposed to continuous treatment (which does not have intermittent vein perforations), may be responsible for the increased symptoms with 810-nm laser vs. RF treatment.18
When using a wavelength strongly absorbed by hemoglobin, such as 810 nm, there is a significant amount of intraluminal blood heating with transmission of heat to the surrounding tissue through long heating times. Temperatures in animal models have been reported as high as 1200°C.18 When we have tried ex-vivo vein treatment without blood, the 810-nm wavelength simply chars a groove along the inside of the vein.
Minimizing Complications
Minimizing direct contact with the vein wall for hemoglobin-dependent methods minimizes the charring of the vein wall and probably lowers the post-operative pain levels. Ideally for a hemoglobin-absorbed wavelength to work, it would be best to have a well-defined layer of hemoglobin between the fiber and the vein wall. In reality, however, varicose veins are not straight segments, but rather saccular and irregular, so that pockets of hemoglobin are frequently encountered, leading to sharp rises in temperature and vein perforations when using hemoglobin-absorbing wavelengths such as 810 nm.
A further concern occurs when using tumescent anesthesia with a hemoglobin-targeting wavelength. It can sometimes be very difficult to gauge the correct amount of solution needed to compress the vein and still leave some intraluminal blood (necessary for the mechanism of action). If too much tumescence is used, and hemoglobin is eliminated, there can be charring of the inner wall of the vein without heating of the vein wall, with resulting pain and failure of vein occlusion.
Targeting Water
In an attempt to circumvent problems associated with hemoglobin-absorbing wavelengths, 1320 nm was investigated for endovenous ablation beginning in 2002. Clinical trials were performed resulting in FDA clearance in September 2004 for treatment of the greater saphenous vein, and in August of 2005 sufficient data for approval for obliteration of reflux in the lesser saphenous vein was cleared by the FDA.
Some laser models with the 1320-nm wavelength use a special conducting laser fiber coupled to an automatic device pre-set to pull back at 1 mm/sec. Tissue water is the target and the presence or absence of red blood cells within the vessels is not relevant to effectiveness of the procedure. This 1.32 micron wavelength is unique among endovenous ablation lasers in that this wavelength is absorbed only by water and not by hemoglobin. (See Figure 4.) This makes it significantly different in mechanism of action compared to the other (hemoglobin targeting) wavelengths used for endovenous laser treatments.
Advantages of 132o nm over 810 nm
The authors’ experience reflects a reduction in pain and bruising of 80% when switching from 810-nm endovenous to 1320-nm endovenous. No significant pain and interference with ambulation, such as observed with 810 nm, has been observed. Having treated more than 200 greater saphenous veins with 1320 nm, our incidence of mild pain is 5% and our success rate of vein ablation is 95% at 2 years. Goldman et al19 have reported a similar experience, concluding that at 6 months follow-up, a 5-W, 1320-nm intravascular laser with 1 mm/s automatic pullback, delivered through a diffusion-tip fiber, is safe and effective in treating an incompetent great saphenous vein up to 1.2 cm in diameter.
It is postulated that there is reduced pain with 1320 nm versus hemoglobin targeting wavelengths probably due to less vein perforations, less thrombus formation and more uniform heating by 1320 nm targeting water in the vein wall. Although rarely patients experience mild pain after 1320 nm, this is probably related to heat dissipated into surrounding tissue, not vein perforations, as the incidence of bruising is extremely low. Cumulative experience in the literature indicates that 1320-nm water targeting versus 810-nm, 940-nm or 980-nm hemoglobin targeting endovenous occlusion is more gentle, leading to far less bruising and post-operative pain. (See Figure 5.)
Summary
The latest techniques for endovenous occlusion using radiofrequency ablation catheters or endoluminal laser targeting water are our preferred methods to treat saphenous-related varicose veins. Clinical experience with endovenous techniques in more than 1,000 patients shows a high degree of success with minimal side effects, most of which can be prevented or minimized with use of tumescent anesthesia.
Tumescent anesthesia is critical to the safety of endovenous techniques. Within the next 5 years, these minimally invasive endovenous ablative procedures involving saphenous trunks should have virtually replaced open surgical strippings. More than 100,000 patients have been already been treated worldwide.
ME Course #131 — June 2007: Lower Extremity Venous Disease and Advances in Techniques for Endovenous Ablation
1. What percentage of lower leg ulcers can be attributable to venous disease?
a. 10% to 20%
b. 30% to 40%
c. 50% to 60%
d. 70% to 80%
e. Less than 10%
2. Which are the main two veins comprising the superficial venous system of the lower extremities?
a. Small saphenous vein
b. Femoral vein
c. Great saphenous vein
d. Popliteal vein
e. Choices A and C
f. Choices B and D
3. Which of the following can occur as a consequence of venous reflux?
a. Superficial venous hypertension
b. Increased diameter of the veins of the
superficial system
c. Non-functioning valves in the superficial
venous system
d. Bulging branches become visible on the
lower extremities
e. Spider veins become more abundant on
the lower extremities
f. All of the above
4. What is the approximate incidence of stasis dermatitis in the United States?
a. 1 to 2 million people
b. 2 to 3 million people
c. 5 to 6 million people
d. 6 to 7 million people
e. Less than 1 million people
5. What percentage of venous disease is due to reflux of the great saphenous vein?
a. None
b. Less than 20%
c. Between 30% to 50%
d. Between 60% to 80%
e. Greater than 85%
6. Which laser wavelengths are most commonly used for endovenous ablation?
a. 532 nm
b. 980 nm
c. 810 nm
d. 1320 nm
e. All of the above
f. Answers B and C
g. Answers B, C, and D
7. What was the first modality approved for endovenous ablation?
a. Steam
b. Laser
c. Radiofrequency
d. Pulsed light
e. None of the above
8. What chromophore is targeted using the CTEV endovenous system (1320-nm laser)
a. Hemoglobin/blood inside the vein
b. Collagen in the vein wall
c. Water in the vein wall
d. A, B, and C
e. None of the above
9. What is the incidence of deep venous thrombosis (DVT) occurring in the immediate post-operative period following endovenous ablation?
a. Less than 3%
b. 80% to 90%
c. 30% to 50%
d. 10% to 20%
e. None of the above
10. What symptoms can occur in patients with superficial venous reflux?
a. Lower leg swelling
b. Throbbing
c. Aching pain
d. Restless legs
e. All of the above
f. None of the above
Skin & Aging is proud to bring you this latest installment in its CME series. This series consists of regular CME activities that qualify you for one category 1 physician credit hour. As a reader of Skin & Aging, this course is brought to you free of charge — you aren’t required to pay a processing fee.
Lower extremity venous disease symptoms and complications range from asymptomatic clusters of spider veins along the medial ankles, to bulging varicose veins extending across the anterior thigh, to stasis dermatitis, leg edema and chronic ulceration of the lower medial calf. Citing the often disappointing results historically achieved with surgery, authors Girish Munavalli, M.D., M.H.S., and Robert A. Weiss, M.D., first describe the pathophysiology of venous disease of the lower and the skin changes that accompany chronic venous disease, then discuss treatment options for eliminating saphenous reflux using endovenous laser ablation techniques.
At the end of this article, you’ll find an exam. Mark your responses in the designated area, then fax page 70 to NACCME at (610) 560-0501.
We’ll also post this course on our Web site, which you can access at www.skinandaging.com. I hope this CME contributes to your clinical skills.
Amy McMichael, M.D.
CME Editor
Principal Faculty: Girish Munavalli, M.D., M.H.S., and Robert A. Weiss, M.D.
Method of Participation: Physicians may receive one category 1 credit by reading the article on pages 64 through 68 and successfully answering the questions found on page 69. A score of 70% is required for passing. Submit your answers and evaluation via fax; or you may log on to our Web site at www.skinandaging.com.
Estimated Time to Complete Activity: 1 hour
Date of Original Release: June 1, 2007
Expiration Date: May 31, 2008
Accreditation Statement: This activity is sponsored by the North American Center for Continuing Medical Education (NACCME). NACCME is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. NACCME designates this educational activity for a maximum of 1 AMA PRA Category 1 Credit.™ Physicians should only claim credit commensurate with the extent of their participation in the activity. This activity has been planned and produced in accordance with the ACCME Essential Areas and Policies.
Disclosures: All those with control over the content of continuing education programs sponsored by NACCME are expected to disclose to the meeting audience any real or apparent conflicts of interest related to the content of their presentation. It is not assumed that these financial interests or affiliations will have an adverse impact on presentations; they are simply noted here to fully inform participants.
Dr. Munavallli has disclosed that he is a member of the speakers' bureau for Cool Touch Lasers.
Dr. Weiss has disclosed that he is a consultant, scientific advisor and has other financial interests in Cool Touch.
Sponsor: This activity is sponsored by the North American Center for Continuing Medical Education.
Learning Objectives:
1.Briefly describe the pathophysiology of venous disease of the lower extremities from small vessel spider veins to saphenous reflux
2. Describe the skin changes that accompany chronic venous disease
3. Discuss treatment options for eliminating saphenous reflux using endovenous laser ablation techniques
Target Audience: Dermatologists, Plastic Surgeons, Internists
Commercial Support: None
Sponsor: NACCME
Clinical manifestations of lower extremity venous disease encompasses a wide spectrum of manifestations, from an asymptomatic cluster of spider veins along the medial ankles, to bulging varicose veins extending across the anterior thigh, to stasis dermatitis, leg edema and chronic ulceration of the lower medial calf.
Phlebology, the science of treatment of venous disease, has roots dating to the ancient Greeks in 400 B.C, at which time venous disease was viewed as problematic and unsightly.1 Procedures involving the use of instrumentation to traumatize veins were described by Hippocrates in the fourth century B.C., and procedures such as rudimentary vein stripping were routinely practiced.1
Venous Insufficiency
Venous disease still presents a formidable challenge to diagnose and treat. Venous insufficiency, which is caused by valvular incompetence in the deep or superficial venous system, is the most common form of venous disease.2 Venous disease affects 40% to 55% of the population, with common symptoms of leg pain, swelling, and skin changes.3 The most common form of lower extremity venous disease is superficial venous insufficiency.
The two major divisions of the superficial venous system are the greater or great saphenous vein (GSV) and lesser or small saphenous vein (LSV). (See Figure 1.) From an anatomical standpoint, the distinction between the two divisions is simple to make. The GSV distribution is along the medial aspect of the leg from the groin to the ankle, while the LSV distribution is along the middle of the posterior calf, from the popliteal fossa to the lower posterior calf.
Venus Insufficiency Causes
Venous insufficiency is the result of incompetence or reflux in either or both of these truncal veins. Greater than 90% of the time, the GSV is the cause of venous insufficiency. Venous insufficiency occurs when a high-pressure leakage develops between the deep and superficial systems or within the superficial system itself, followed by sequential failure of the venous valves in superficial veins. This allows venous blood to escape from its normal flow path and to flow in a retrograde direction down into an already congested leg. Over time, incompetent truncal veins acquire the typical dilated and tortuous appearance of varicosities.
Associated Skin Changes
Furthermore, insufficiency can lead to chronic morbidity in the form of ulcerative, edematous, and pigmentary skin changes in the lower extremities. One such example of a skin change, which is a direct consequence of venous insufficiency, is stasis dermatitis. (See Figure 2.)
Stasis dermatitis has an estimated prevalence of 6% to 7% in adults over the age of 50. In the United States, this is thought to be between 6 and 7 million people.4 As mentioned, abnormal function of the one-way venous valvular system in the deep and superficial venous systems of the legs results in backflow of blood from the deep venous system and perforating veins to the superficial venous system, with accompanying venous hypertension.
Causes of loss of valvular function include: genetic predisposition, hormonal influences from pregnancy, trauma, and an age-related decrease in valve competency. Other events, such as deep venous thrombosis or prior vein surgery, can severely damage the lower-extremity venous system function and cause valvular incompetence.
The mechanism by which venous hypertension causes skin inflammation and stasis dermatitis has been extensively studied. It is thought that increased venous hydrostatic pressure is transmitted to the dermal microcirculation, leading to increased permeability of dermal capillaries. This increased permeability enables plasma macromolecules, such as fibrinogen, to leak out of the vasculature into the pericapillary tissue; then, polymerization of fibrinogen to fibrin results in the formation of a fibrin cuff around dermal capillaries, further congesting flow.4
Stasis dermatitis frequently occurs along with a background of skin changes typical for venous insufficiency patients. Changes include edema, varicosities, hyperpigmentation, atrophic patches (atrophie blanche), and diffuse red-brown discoloration representing deep dermal deposits of hemosiderin (from degraded, extravasated erythrocytes). Often, these chronic changes persist despite stasis dermatitis activity.5
Complications That Can Occur
The dreaded complication of skin ulceration often occurs with chronic stasis dermatitis and accompanying edema. It is thought that 60% to 70% of lower leg ulcers can be attributed to venous disease. Aside from skin changes, patients also experience other nagging symptoms such as lower leg throbbing, swelling, itching, aching pain and restless leg tendencies.
Preventing Skin Changes
To prevent chronic skin changes from venous reflux as well as avoid the daily occurrence of pain, definitive treatment for venous hypertension should be sought as soon as possible.
Surgical Correction
Historically, methods for surgical correction have included vein stripping, ligation and division, echosclerotherapy, and valve replacement. Vein stripping has a failure rate as high as 60%6,7,8 and requires general or spinal anesthesia. Recovery times can often take 2 to 3 weeks. Similar to vein stripping, the reported incidence rate for GSV reflux following high ligation alone is significant with up to 71% recurrence.6,7 Postulated reasons for this include under-recognized anomalous anatomic vascular patterns in the saphenous systems and neo-vascularization.
Endovenous Laser Treatment
In 2002, the FDA approved endovenous laser treatment as a minimally invasive method of ablating incompetent saphenous veins. This in-office procedure uses local anesthesia, thus eliminating the need for general or spinal anesthesia, and the inherent risks associated with them.
The use of endovenous procedures to eliminate saphenous and primary branch reflux has been growing exponentially over the last few years. In stark contrast to the very invasive nature of stripping and ligation, the concept of obtaining percutaneous access to a vein under local anesthesia and using a form of directed laser energy from the inside to shrink and seal the targeted vein allows for quick patient recovery. (See Figure 3.)
Although initially developed by dermatologic surgeons, the endovenous ablation has been embraced by many other specialties including radiology, vascular surgery and anesthesiology.
It began with the use of a specially and elegantly designed bipolar radiofrequency (RF) catheter for gentle heating and was quickly applied to bare laser fibers fired within the targeted varicose or refluxing saphenous vein.9 With worldwide clinical experience of more than 60,000 procedures since 1999, radiofrequency shrinkage of veins has been a valuable addition to treating large varicose veins resulting from saphenous reflux.
Today there are numerous systems available that utilize various infrared wavelengths as well as radiofrequency to accomplish endoluminal heating and shrinkage of saphenous trunks.
Endovenous Laser Treatment
The following discussion will focus on two classes of laser endovenous treatment: lasers targeting hemoglobin (810 nm, 940 nm and 980 nm) within blood inside the vein, and lasers targeting water in the vein wall (1320 nm).
Utilization of Tumescent Anesthesia
As a prelude to this discussion, it is important to emphasize the role of tumescent anesthesia in reducing side effects following endovenous laser ablation. Dermatologic surgeons, experienced with large-volume, low-concentration tumescent anesthesia for liposuction and other surgical procedures, were the first to apply tumescent infiltration to endovenous techniques.
Tumescent anesthesia or the placement of large volumes of dilute anesthesia in a peri-vascular position, under the direction of duplex guidance, serves several purposes:
- It protects peri-vascular tissues from the thermal effects of intravascular energy by serving as a heat sink.
- It decreases the diameter of the treated vein to allow for better absorption of energy by the target chromophore and thus secondarily reduce intravascular blood for non-specific coagulation.
- It provides more effective and safer anesthesia for patients.
Using tumescent anesthesia, the GSV could be sealed with endovenous techniques as a totally painless procedure with little downtime and immediate ambulation of the patient.
From the authors’ experience with tumescent anesthesia (utilized in every endovenous ablation surgical case), the technique is vital to prevent the formation of deep vein thrombosis (DVT). The incidence of DVT as measured by duplex ultrasound follow-up at 3 to 14 days is 0% (personal communication, R. Weiss, M.D.). It is our firm belief that the use of tumescent anesthesia in non-sedated, conscious patients followed by immediate ambulation at the conclusion of the procedure is the reason for lack of serious adverse sequelae such as DVT.
Targeting Hemoglobin
Endovenous laser treatment allows delivery of laser energy directly into the blood vessel lumen in order to produce endothelial and vein wall damage with subsequent fibrosis. The various lasers available for endovenous are summarized in Table 1.
The presumed target for lasers with 810-nm, 940-nm, and 980-nm wavelengths is intravascular red blood cell absorption of laser energy with dissipation of heat and thrombotic vein occlusion with some intramural heat damage.
Steam bubbles occurring as blood is boiled within the lumen have been shown to occur as the primary mechanism for hemoglobin targeting laser endovenous occlusion effects.10
Direct thermal effects on the vein wall without the presence of blood probably do not occur.11 The extent of thermal injury to tissue depends strongly on the amount and duration of heat the tissue is exposed to, which for these lasers depends on multiple factors including blood in the lumen, rate of pullback and amount of tumescent anesthesia placed around the vein.12
Initial reports have shown this technique with an 810-nm diode laser to have good short-term efficacy in the treatment of the incompetent GSV, with 96% or higher occlusion at 9 months with a less than 1% incidence of transient paresthesia.13,14 More recently, 2-year follow-up of 499 limbs has been completed with a recurrence rate of less than 7% at 2-year follow-up. However, 90% of these patients experienced degrees of post-operative ecchymosis and varying degrees of discomfort.15 Skin burns have been observed by our center and recently have been reported using the 810-nm wavelength.16 DVT extending into the femoral vein recently has also been reported with endovenous laser treatment.17
Post-Treatment Effects
Patients treated with an 810-nm diode laser have shown an increase in post-treatment purpura and tenderness. Most patients do not return to complete functional normality for 2 to 7 days as opposed to the 1 day “down-time” with RF closure of the GSV. Recent studies suggest that pulsed 810-nm diode laser treatment, with its increased risk for perforation of the vein as opposed to continuous treatment (which does not have intermittent vein perforations), may be responsible for the increased symptoms with 810-nm laser vs. RF treatment.18
When using a wavelength strongly absorbed by hemoglobin, such as 810 nm, there is a significant amount of intraluminal blood heating with transmission of heat to the surrounding tissue through long heating times. Temperatures in animal models have been reported as high as 1200°C.18 When we have tried ex-vivo vein treatment without blood, the 810-nm wavelength simply chars a groove along the inside of the vein.
Minimizing Complications
Minimizing direct contact with the vein wall for hemoglobin-dependent methods minimizes the charring of the vein wall and probably lowers the post-operative pain levels. Ideally for a hemoglobin-absorbed wavelength to work, it would be best to have a well-defined layer of hemoglobin between the fiber and the vein wall. In reality, however, varicose veins are not straight segments, but rather saccular and irregular, so that pockets of hemoglobin are frequently encountered, leading to sharp rises in temperature and vein perforations when using hemoglobin-absorbing wavelengths such as 810 nm.
A further concern occurs when using tumescent anesthesia with a hemoglobin-targeting wavelength. It can sometimes be very difficult to gauge the correct amount of solution needed to compress the vein and still leave some intraluminal blood (necessary for the mechanism of action). If too much tumescence is used, and hemoglobin is eliminated, there can be charring of the inner wall of the vein without heating of the vein wall, with resulting pain and failure of vein occlusion.
Targeting Water
In an attempt to circumvent problems associated with hemoglobin-absorbing wavelengths, 1320 nm was investigated for endovenous ablation beginning in 2002. Clinical trials were performed resulting in FDA clearance in September 2004 for treatment of the greater saphenous vein, and in August of 2005 sufficient data for approval for obliteration of reflux in the lesser saphenous vein was cleared by the FDA.
Some laser models with the 1320-nm wavelength use a special conducting laser fiber coupled to an automatic device pre-set to pull back at 1 mm/sec. Tissue water is the target and the presence or absence of red blood cells within the vessels is not relevant to effectiveness of the procedure. This 1.32 micron wavelength is unique among endovenous ablation lasers in that this wavelength is absorbed only by water and not by hemoglobin. (See Figure 4.) This makes it significantly different in mechanism of action compared to the other (hemoglobin targeting) wavelengths used for endovenous laser treatments.
Advantages of 132o nm over 810 nm
The authors’ experience reflects a reduction in pain and bruising of 80% when switching from 810-nm endovenous to 1320-nm endovenous. No significant pain and interference with ambulation, such as observed with 810 nm, has been observed. Having treated more than 200 greater saphenous veins with 1320 nm, our incidence of mild pain is 5% and our success rate of vein ablation is 95% at 2 years. Goldman et al19 have reported a similar experience, concluding that at 6 months follow-up, a 5-W, 1320-nm intravascular laser with 1 mm/s automatic pullback, delivered through a diffusion-tip fiber, is safe and effective in treating an incompetent great saphenous vein up to 1.2 cm in diameter.
It is postulated that there is reduced pain with 1320 nm versus hemoglobin targeting wavelengths probably due to less vein perforations, less thrombus formation and more uniform heating by 1320 nm targeting water in the vein wall. Although rarely patients experience mild pain after 1320 nm, this is probably related to heat dissipated into surrounding tissue, not vein perforations, as the incidence of bruising is extremely low. Cumulative experience in the literature indicates that 1320-nm water targeting versus 810-nm, 940-nm or 980-nm hemoglobin targeting endovenous occlusion is more gentle, leading to far less bruising and post-operative pain. (See Figure 5.)
Summary
The latest techniques for endovenous occlusion using radiofrequency ablation catheters or endoluminal laser targeting water are our preferred methods to treat saphenous-related varicose veins. Clinical experience with endovenous techniques in more than 1,000 patients shows a high degree of success with minimal side effects, most of which can be prevented or minimized with use of tumescent anesthesia.
Tumescent anesthesia is critical to the safety of endovenous techniques. Within the next 5 years, these minimally invasive endovenous ablative procedures involving saphenous trunks should have virtually replaced open surgical strippings. More than 100,000 patients have been already been treated worldwide.
ME Course #131 — June 2007: Lower Extremity Venous Disease and Advances in Techniques for Endovenous Ablation
1. What percentage of lower leg ulcers can be attributable to venous disease?
a. 10% to 20%
b. 30% to 40%
c. 50% to 60%
d. 70% to 80%
e. Less than 10%
2. Which are the main two veins comprising the superficial venous system of the lower extremities?
a. Small saphenous vein
b. Femoral vein
c. Great saphenous vein
d. Popliteal vein
e. Choices A and C
f. Choices B and D
3. Which of the following can occur as a consequence of venous reflux?
a. Superficial venous hypertension
b. Increased diameter of the veins of the
superficial system
c. Non-functioning valves in the superficial
venous system
d. Bulging branches become visible on the
lower extremities
e. Spider veins become more abundant on
the lower extremities
f. All of the above
4. What is the approximate incidence of stasis dermatitis in the United States?
a. 1 to 2 million people
b. 2 to 3 million people
c. 5 to 6 million people
d. 6 to 7 million people
e. Less than 1 million people
5. What percentage of venous disease is due to reflux of the great saphenous vein?
a. None
b. Less than 20%
c. Between 30% to 50%
d. Between 60% to 80%
e. Greater than 85%
6. Which laser wavelengths are most commonly used for endovenous ablation?
a. 532 nm
b. 980 nm
c. 810 nm
d. 1320 nm
e. All of the above
f. Answers B and C
g. Answers B, C, and D
7. What was the first modality approved for endovenous ablation?
a. Steam
b. Laser
c. Radiofrequency
d. Pulsed light
e. None of the above
8. What chromophore is targeted using the CTEV endovenous system (1320-nm laser)
a. Hemoglobin/blood inside the vein
b. Collagen in the vein wall
c. Water in the vein wall
d. A, B, and C
e. None of the above
9. What is the incidence of deep venous thrombosis (DVT) occurring in the immediate post-operative period following endovenous ablation?
a. Less than 3%
b. 80% to 90%
c. 30% to 50%
d. 10% to 20%
e. None of the above
10. What symptoms can occur in patients with superficial venous reflux?
a. Lower leg swelling
b. Throbbing
c. Aching pain
d. Restless legs
e. All of the above
f. None of the above
Skin & Aging is proud to bring you this latest installment in its CME series. This series consists of regular CME activities that qualify you for one category 1 physician credit hour. As a reader of Skin & Aging, this course is brought to you free of charge — you aren’t required to pay a processing fee.
Lower extremity venous disease symptoms and complications range from asymptomatic clusters of spider veins along the medial ankles, to bulging varicose veins extending across the anterior thigh, to stasis dermatitis, leg edema and chronic ulceration of the lower medial calf. Citing the often disappointing results historically achieved with surgery, authors Girish Munavalli, M.D., M.H.S., and Robert A. Weiss, M.D., first describe the pathophysiology of venous disease of the lower and the skin changes that accompany chronic venous disease, then discuss treatment options for eliminating saphenous reflux using endovenous laser ablation techniques.
At the end of this article, you’ll find an exam. Mark your responses in the designated area, then fax page 70 to NACCME at (610) 560-0501.
We’ll also post this course on our Web site, which you can access at www.skinandaging.com. I hope this CME contributes to your clinical skills.
Amy McMichael, M.D.
CME Editor
Principal Faculty: Girish Munavalli, M.D., M.H.S., and Robert A. Weiss, M.D.
Method of Participation: Physicians may receive one category 1 credit by reading the article on pages 64 through 68 and successfully answering the questions found on page 69. A score of 70% is required for passing. Submit your answers and evaluation via fax; or you may log on to our Web site at www.skinandaging.com.
Estimated Time to Complete Activity: 1 hour
Date of Original Release: June 1, 2007
Expiration Date: May 31, 2008
Accreditation Statement: This activity is sponsored by the North American Center for Continuing Medical Education (NACCME). NACCME is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. NACCME designates this educational activity for a maximum of 1 AMA PRA Category 1 Credit.™ Physicians should only claim credit commensurate with the extent of their participation in the activity. This activity has been planned and produced in accordance with the ACCME Essential Areas and Policies.
Disclosures: All those with control over the content of continuing education programs sponsored by NACCME are expected to disclose to the meeting audience any real or apparent conflicts of interest related to the content of their presentation. It is not assumed that these financial interests or affiliations will have an adverse impact on presentations; they are simply noted here to fully inform participants.
Dr. Munavallli has disclosed that he is a member of the speakers' bureau for Cool Touch Lasers.
Dr. Weiss has disclosed that he is a consultant, scientific advisor and has other financial interests in Cool Touch.
Sponsor: This activity is sponsored by the North American Center for Continuing Medical Education.
Learning Objectives:
1.Briefly describe the pathophysiology of venous disease of the lower extremities from small vessel spider veins to saphenous reflux
2. Describe the skin changes that accompany chronic venous disease
3. Discuss treatment options for eliminating saphenous reflux using endovenous laser ablation techniques
Target Audience: Dermatologists, Plastic Surgeons, Internists
Commercial Support: None
Sponsor: NACCME
Clinical manifestations of lower extremity venous disease encompasses a wide spectrum of manifestations, from an asymptomatic cluster of spider veins along the medial ankles, to bulging varicose veins extending across the anterior thigh, to stasis dermatitis, leg edema and chronic ulceration of the lower medial calf.
Phlebology, the science of treatment of venous disease, has roots dating to the ancient Greeks in 400 B.C, at which time venous disease was viewed as problematic and unsightly.1 Procedures involving the use of instrumentation to traumatize veins were described by Hippocrates in the fourth century B.C., and procedures such as rudimentary vein stripping were routinely practiced.1
Venous Insufficiency
Venous disease still presents a formidable challenge to diagnose and treat. Venous insufficiency, which is caused by valvular incompetence in the deep or superficial venous system, is the most common form of venous disease.2 Venous disease affects 40% to 55% of the population, with common symptoms of leg pain, swelling, and skin changes.3 The most common form of lower extremity venous disease is superficial venous insufficiency.
The two major divisions of the superficial venous system are the greater or great saphenous vein (GSV) and lesser or small saphenous vein (LSV). (See Figure 1.) From an anatomical standpoint, the distinction between the two divisions is simple to make. The GSV distribution is along the medial aspect of the leg from the groin to the ankle, while the LSV distribution is along the middle of the posterior calf, from the popliteal fossa to the lower posterior calf.
Venus Insufficiency Causes
Venous insufficiency is the result of incompetence or reflux in either or both of these truncal veins. Greater than 90% of the time, the GSV is the cause of venous insufficiency. Venous insufficiency occurs when a high-pressure leakage develops between the deep and superficial systems or within the superficial system itself, followed by sequential failure of the venous valves in superficial veins. This allows venous blood to escape from its normal flow path and to flow in a retrograde direction down into an already congested leg. Over time, incompetent truncal veins acquire the typical dilated and tortuous appearance of varicosities.
Associated Skin Changes
Furthermore, insufficiency can lead to chronic morbidity in the form of ulcerative, edematous, and pigmentary skin changes in the lower extremities. One such example of a skin change, which is a direct consequence of venous insufficiency, is stasis dermatitis. (See Figure 2.)
Stasis dermatitis has an estimated prevalence of 6% to 7% in adults over the age of 50. In the United States, this is thought to be between 6 and 7 million people.4 As mentioned, abnormal function of the one-way venous valvular system in the deep and superficial venous systems of the legs results in backflow of blood from the deep venous system and perforating veins to the superficial venous system, with accompanying venous hypertension.
Causes of loss of valvular function include: genetic predisposition, hormonal influences from pregnancy, trauma, and an age-related decrease in valve competency. Other events, such as deep venous thrombosis or prior vein surgery, can severely damage the lower-extremity venous system function and cause valvular incompetence.
The mechanism by which venous hypertension causes skin inflammation and stasis dermatitis has been extensively studied. It is thought that increased venous hydrostatic pressure is transmitted to the dermal microcirculation, leading to increased permeability of dermal capillaries. This increased permeability enables plasma macromolecules, such as fibrinogen, to leak out of the vasculature into the pericapillary tissue; then, polymerization of fibrinogen to fibrin results in the formation of a fibrin cuff around dermal capillaries, further congesting flow.4
Stasis dermatitis frequently occurs along with a background of skin changes typical for venous insufficiency patients. Changes include edema, varicosities, hyperpigmentation, atrophic patches (atrophie blanche), and diffuse red-brown discoloration representing deep dermal deposits of hemosiderin (from degraded, extravasated erythrocytes). Often, these chronic changes persist despite stasis dermatitis activity.5
Complications That Can Occur
The dreaded complication of skin ulceration often occurs with chronic stasis dermatitis and accompanying edema. It is thought that 60% to 70% of lower leg ulcers can be attributed to venous disease. Aside from skin changes, patients also experience other nagging symptoms such as lower leg throbbing, swelling, itching, aching pain and restless leg tendencies.
Preventing Skin Changes
To prevent chronic skin changes from venous reflux as well as avoid the daily occurrence of pain, definitive treatment for venous hypertension should be sought as soon as possible.
Surgical Correction
Historically, methods for surgical correction have included vein stripping, ligation and division, echosclerotherapy, and valve replacement. Vein stripping has a failure rate as high as 60%6,7,8 and requires general or spinal anesthesia. Recovery times can often take 2 to 3 weeks. Similar to vein stripping, the reported incidence rate for GSV reflux following high ligation alone is significant with up to 71% recurrence.6,7 Postulated reasons for this include under-recognized anomalous anatomic vascular patterns in the saphenous systems and neo-vascularization.
Endovenous Laser Treatment
In 2002, the FDA approved endovenous laser treatment as a minimally invasive method of ablating incompetent saphenous veins. This in-office procedure uses local anesthesia, thus eliminating the need for general or spinal anesthesia, and the inherent risks associated with them.
The use of endovenous procedures to eliminate saphenous and primary branch reflux has been growing exponentially over the last few years. In stark contrast to the very invasive nature of stripping and ligation, the concept of obtaining percutaneous access to a vein under local anesthesia and using a form of directed laser energy from the inside to shrink and seal the targeted vein allows for quick patient recovery. (See Figure 3.)
Although initially developed by dermatologic surgeons, the endovenous ablation has been embraced by many other specialties including radiology, vascular surgery and anesthesiology.
It began with the use of a specially and elegantly designed bipolar radiofrequency (RF) catheter for gentle heating and was quickly applied to bare laser fibers fired within the targeted varicose or refluxing saphenous vein.9 With worldwide clinical experience of more than 60,000 procedures since 1999, radiofrequency shrinkage of veins has been a valuable addition to treating large varicose veins resulting from saphenous reflux.
Today there are numerous systems available that utilize various infrared wavelengths as well as radiofrequency to accomplish endoluminal heating and shrinkage of saphenous trunks.
Endovenous Laser Treatment
The following discussion will focus on two classes of laser endovenous treatment: lasers targeting hemoglobin (810 nm, 940 nm and 980 nm) within blood inside the vein, and lasers targeting water in the vein wall (1320 nm).
Utilization of Tumescent Anesthesia
As a prelude to this discussion, it is important to emphasize the role of tumescent anesthesia in reducing side effects following endovenous laser ablation. Dermatologic surgeons, experienced with large-volume, low-concentration tumescent anesthesia for liposuction and other surgical procedures, were the first to apply tumescent infiltration to endovenous techniques.
Tumescent anesthesia or the placement of large volumes of dilute anesthesia in a peri-vascular position, under the direction of duplex guidance, serves several purposes:
- It protects peri-vascular tissues from the thermal effects of intravascular energy by serving as a heat sink.
- It decreases the diameter of the treated vein to allow for better absorption of energy by the target chromophore and thus secondarily reduce intravascular blood for non-specific coagulation.
- It provides more effective and safer anesthesia for patients.
Using tumescent anesthesia, the GSV could be sealed with endovenous techniques as a totally painless procedure with little downtime and immediate ambulation of the patient.
From the authors’ experience with tumescent anesthesia (utilized in every endovenous ablation surgical case), the technique is vital to prevent the formation of deep vein thrombosis (DVT). The incidence of DVT as measured by duplex ultrasound follow-up at 3 to 14 days is 0% (personal communication, R. Weiss, M.D.). It is our firm belief that the use of tumescent anesthesia in non-sedated, conscious patients followed by immediate ambulation at the conclusion of the procedure is the reason for lack of serious adverse sequelae such as DVT.
Targeting Hemoglobin
Endovenous laser treatment allows delivery of laser energy directly into the blood vessel lumen in order to produce endothelial and vein wall damage with subsequent fibrosis. The various lasers available for endovenous are summarized in Table 1.
The presumed target for lasers with 810-nm, 940-nm, and 980-nm wavelengths is intravascular red blood cell absorption of laser energy with dissipation of heat and thrombotic vein occlusion with some intramural heat damage.
Steam bubbles occurring as blood is boiled within the lumen have been shown to occur as the primary mechanism for hemoglobin targeting laser endovenous occlusion effects.10
Direct thermal effects on the vein wall without the presence of blood probably do not occur.11 The extent of thermal injury to tissue depends strongly on the amount and duration of heat the tissue is exposed to, which for these lasers depends on multiple factors including blood in the lumen, rate of pullback and amount of tumescent anesthesia placed around the vein.12
Initial reports have shown this technique with an 810-nm diode laser to have good short-term efficacy in the treatment of the incompetent GSV, with 96% or higher occlusion at 9 months with a less than 1% incidence of transient paresthesia.13,14 More recently, 2-year follow-up of 499 limbs has been completed with a recurrence rate of less than 7% at 2-year follow-up. However, 90% of these patients experienced degrees of post-operative ecchymosis and varying degrees of discomfort.15 Skin burns have been observed by our center and recently have been reported using the 810-nm wavelength.16 DVT extending into the femoral vein recently has also been reported with endovenous laser treatment.17
Post-Treatment Effects
Patients treated with an 810-nm diode laser have shown an increase in post-treatment purpura and tenderness. Most patients do not return to complete functional normality for 2 to 7 days as opposed to the 1 day “down-time” with RF closure of the GSV. Recent studies suggest that pulsed 810-nm diode laser treatment, with its increased risk for perforation of the vein as opposed to continuous treatment (which does not have intermittent vein perforations), may be responsible for the increased symptoms with 810-nm laser vs. RF treatment.18
When using a wavelength strongly absorbed by hemoglobin, such as 810 nm, there is a significant amount of intraluminal blood heating with transmission of heat to the surrounding tissue through long heating times. Temperatures in animal models have been reported as high as 1200°C.18 When we have tried ex-vivo vein treatment without blood, the 810-nm wavelength simply chars a groove along the inside of the vein.
Minimizing Complications
Minimizing direct contact with the vein wall for hemoglobin-dependent methods minimizes the charring of the vein wall and probably lowers the post-operative pain levels. Ideally for a hemoglobin-absorbed wavelength to work, it would be best to have a well-defined layer of hemoglobin between the fiber and the vein wall. In reality, however, varicose veins are not straight segments, but rather saccular and irregular, so that pockets of hemoglobin are frequently encountered, leading to sharp rises in temperature and vein perforations when using hemoglobin-absorbing wavelengths such as 810 nm.
A further concern occurs when using tumescent anesthesia with a hemoglobin-targeting wavelength. It can sometimes be very difficult to gauge the correct amount of solution needed to compress the vein and still leave some intraluminal blood (necessary for the mechanism of action). If too much tumescence is used, and hemoglobin is eliminated, there can be charring of the inner wall of the vein without heating of the vein wall, with resulting pain and failure of vein occlusion.
Targeting Water
In an attempt to circumvent problems associated with hemoglobin-absorbing wavelengths, 1320 nm was investigated for endovenous ablation beginning in 2002. Clinical trials were performed resulting in FDA clearance in September 2004 for treatment of the greater saphenous vein, and in August of 2005 sufficient data for approval for obliteration of reflux in the lesser saphenous vein was cleared by the FDA.
Some laser models with the 1320-nm wavelength use a special conducting laser fiber coupled to an automatic device pre-set to pull back at 1 mm/sec. Tissue water is the target and the presence or absence of red blood cells within the vessels is not relevant to effectiveness of the procedure. This 1.32 micron wavelength is unique among endovenous ablation lasers in that this wavelength is absorbed only by water and not by hemoglobin. (See Figure 4.) This makes it significantly different in mechanism of action compared to the other (hemoglobin targeting) wavelengths used for endovenous laser treatments.
Advantages of 132o nm over 810 nm
The authors’ experience reflects a reduction in pain and bruising of 80% when switching from 810-nm endovenous to 1320-nm endovenous. No significant pain and interference with ambulation, such as observed with 810 nm, has been observed. Having treated more than 200 greater saphenous veins with 1320 nm, our incidence of mild pain is 5% and our success rate of vein ablation is 95% at 2 years. Goldman et al19 have reported a similar experience, concluding that at 6 months follow-up, a 5-W, 1320-nm intravascular laser with 1 mm/s automatic pullback, delivered through a diffusion-tip fiber, is safe and effective in treating an incompetent great saphenous vein up to 1.2 cm in diameter.
It is postulated that there is reduced pain with 1320 nm versus hemoglobin targeting wavelengths probably due to less vein perforations, less thrombus formation and more uniform heating by 1320 nm targeting water in the vein wall. Although rarely patients experience mild pain after 1320 nm, this is probably related to heat dissipated into surrounding tissue, not vein perforations, as the incidence of bruising is extremely low. Cumulative experience in the literature indicates that 1320-nm water targeting versus 810-nm, 940-nm or 980-nm hemoglobin targeting endovenous occlusion is more gentle, leading to far less bruising and post-operative pain. (See Figure 5.)
Summary
The latest techniques for endovenous occlusion using radiofrequency ablation catheters or endoluminal laser targeting water are our preferred methods to treat saphenous-related varicose veins. Clinical experience with endovenous techniques in more than 1,000 patients shows a high degree of success with minimal side effects, most of which can be prevented or minimized with use of tumescent anesthesia.
Tumescent anesthesia is critical to the safety of endovenous techniques. Within the next 5 years, these minimally invasive endovenous ablative procedures involving saphenous trunks should have virtually replaced open surgical strippings. More than 100,000 patients have been already been treated worldwide.
ME Course #131 — June 2007: Lower Extremity Venous Disease and Advances in Techniques for Endovenous Ablation
1. What percentage of lower leg ulcers can be attributable to venous disease?
a. 10% to 20%
b. 30% to 40%
c. 50% to 60%
d. 70% to 80%
e. Less than 10%
2. Which are the main two veins comprising the superficial venous system of the lower extremities?
a. Small saphenous vein
b. Femoral vein
c. Great saphenous vein
d. Popliteal vein
e. Choices A and C
f. Choices B and D
3. Which of the following can occur as a consequence of venous reflux?
a. Superficial venous hypertension
b. Increased diameter of the veins of the
superficial system
c. Non-functioning valves in the superficial
venous system
d. Bulging branches become visible on the
lower extremities
e. Spider veins become more abundant on
the lower extremities
f. All of the above
4. What is the approximate incidence of stasis dermatitis in the United States?
a. 1 to 2 million people
b. 2 to 3 million people
c. 5 to 6 million people
d. 6 to 7 million people
e. Less than 1 million people
5. What percentage of venous disease is due to reflux of the great saphenous vein?
a. None
b. Less than 20%
c. Between 30% to 50%
d. Between 60% to 80%
e. Greater than 85%
6. Which laser wavelengths are most commonly used for endovenous ablation?
a. 532 nm
b. 980 nm
c. 810 nm
d. 1320 nm
e. All of the above
f. Answers B and C
g. Answers B, C, and D
7. What was the first modality approved for endovenous ablation?
a. Steam
b. Laser
c. Radiofrequency
d. Pulsed light
e. None of the above
8. What chromophore is targeted using the CTEV endovenous system (1320-nm laser)
a. Hemoglobin/blood inside the vein
b. Collagen in the vein wall
c. Water in the vein wall
d. A, B, and C
e. None of the above
9. What is the incidence of deep venous thrombosis (DVT) occurring in the immediate post-operative period following endovenous ablation?
a. Less than 3%
b. 80% to 90%
c. 30% to 50%
d. 10% to 20%
e. None of the above
10. What symptoms can occur in patients with superficial venous reflux?
a. Lower leg swelling
b. Throbbing
c. Aching pain
d. Restless legs
e. All of the above
f. None of the above
