Calf Perforators Research Articles

The athlete's vein: venous adaptations in the lower limbs of endurance athletes.

Endurance exercise induces cardiovascular adaptations; the athletic phenotypes of the heart and arteries are well characterized, but few studies have investigated the effects of chronic exercise on the venous system. The aim of this study was to describe the anatomy and function of lower-limb deep and superficial veins in athletes compared with controls. Endurance-trained athletes and untrained controls (13 males, 7 females per group) were examined using ultrasound to measure vein diameter and flow, and air plethysmography to assess calf venous volume dynamics and muscle pump function at rest, during a single step, ambulation (10 steps) and after acute treadmill exercise (30 min ∼80% age-predicted heart rate maximum). Diameters of three of the seven deep veins assessed were larger in athletes (P ≤ 0.0167) and more medial calf perforators were detectable (5 vs. 3, P = 0.0039). Calf venous volume was 22% larger in athletes (P = 0.0057), and calf muscle pump ejection volume and ambulatory venous volume after 10 steps were both greater in athletes (20 and 46% respectively, P ≤ 0.0482). Following acute exercise, flow recovery profiles in deep and superficial veins draining the leg were not different between groups, despite athletes performing approximately four times more work. After exercise, venous volume and ejection volume were reduced by ∼20% in athletes with no change in controls (interaction, P ≤ 0.0372) and although ambulatory venous volume reduced, this remained greater in athletes. These findings highlight venous adaptations that compensate for the demands of regular endurance exercise, all of which are suited to enhance flow through the lower-limb venous system.NEW & NOTEWORTHY Although much literature exists describing adaptations to the heart and arteries in response to endurance exercise training, less is known about the effects on the venous system. Characteristics of "the athlete's vein" described here include deep and perforator vein remodeling, improved drainage, and greater calf venous volume at rest and on calf muscle pump activation. Following exercise, athletes demonstrated prompt flow recovery and appropriate volume reductions, and veins beneficially adapt to better tolerate the demands of regular physical activity.

Historical view onto the contribution of phlebodynamometry to the knowledge of venous hemodynamics in the lower extremity

Contribution of phlebodynamometry to the knowledge of the venous hemodynamics in the lower extremity is assessed from the historical point of view. Höjensgard, Stürup, and Arnoldi yielded in the 50's and 60's of the last century substantial information concerning changes of venous pressure in superficial and deep veins of the lower extremity arising during calf pump activity. They confirmed the previous finding that the venous pressure in the quiet standing position corresponds to the column of blood extending from the point of measurement to the heart. During calf pump activity, the systolic-diastolic amplitudes in lower leg veins are very marked; in contrast to that, they are only modest in the popliteal vein. The mentioned authors documented marked decrease in pressure in the posterior tibial vein as well as in the great saphenous vein arising during calf pump activity in healthy people. Contrary to that, the pressure in the popliteal vein did not decrease; it kept principally the value of the resting hydrostatic pressure. This difference of pressure between the thigh veins and the lower leg veins has been called ambulatory pressure gradient; its value in the examined patient cohort was 37.4±6.4 mm Hg. Ambulatory pressure gradient constitutes the suction force that triggers reflux in incompetent superficial and deep veins; this refluxing flow causes ambulatory venous hypertension. Simultaneous pressure recordings in the posterior tibial vein and great saphenous vein in healthy volunteers documented that the systolic and diastolic pressure amplitudes were similar in both veins. The systolic pressure in the posterior tibial vein increased on average by 75 mm Hg; this generates a strong impulse propelling the venous blood mainly into the popliteal vein, and partially into the great saphenous vein. Thus, there is a double-barreled outflow of venous blood from the lower extremity toward the heart. The steep increase in systolic pressure in the great saphenous vein gave evidence of the incompetence of the calf perforators system in healthy people. At present, plethysmography is able to yield similar information on the hemodynamic status of the lower limbs like phlebodynamometry.

Characteristics of venous leg ulcer patients at a tertiary wound care center

ObjectiveThe objective of this study was to assess patient, wound, care, and reflux characteristics of venous leg ulcers (VLUs) to update and improve knowledge of disease etiology, identify barriers to healing, and improve treatment. MethodsPatients diagnosed with VLUs treated at the Stanford Advanced Wound Care Center between 2018 and 2019 were identified from the Healogics iHeal database. We identified 327 VLU entries, of which 133 were patients who had multiple or recurring wounds. An additional 27 patients were labeled as misdiagnosis, resulting in a final patient sample of 167. Patient demographics, wound, care, and ultrasound data for these patients were extracted from the Stanford electronic medical records regarding characteristics. The initial data analysis suggested possible differences in VLU characteristics depending on patient age and body mass index (BMI), which was then further analyzed. ResultsOf the 167 VLU patients assessed, 53.9% were male and 46.1% were female. The mean age was 74.7 years, and the average BMI was 30.2 kg/m2, including 41.1% of patients with a BMI over 30 kg/m2. Approximately 50% of wounds were presented in multiples, had cellulitis, or were recurring, and 39.5% were caused by trauma. Most common venous reflux patterns on duplex ultrasound examination were below-knee great saphenous vein reflux and calf perforator reflux, which was identified in 37.7% and 29.3% of the patients, respectively. Axial great saphenous vein reflux was detected in 14.4% of patients. When looking at the patient sample under 60 years of age, 67.7% were male, 61.3% presented with venous skin changes, and 51.6% had diabetes. In the patients older than 60, only 51.9% were male, 37.6% presented with venous skin changes, and 31.6% had diabetes. BMI was greater in the patients under age 60, with an average of 39.2 kg/m2, compared with 28.2 kg/m2 in those above 60. Of the patients with a BMI ≥30 kg/m2, 64.3% had multiple wounds, 61.4% had recurring wounds, and 56.5% had venous skin changes. In contrast, in patients with BMI <30 kg/m2, 47.4% had multiple wounds, 39.2% had recurring wounds, and 32.0% had venous skin changes. ConclusionsVLU pathology appears to differ depending on patient demographics and characteristics. Different drivers may influence disease cause, progression, and prognosis, making a standard approach to VLUs difficult. Our findings suggest that identifying different subtypes of VLUs and adapting an algorithm of care with a personalized treatment may help optimize management of these patients.

The lower limb perforator veins in normal subjects

ObjectiveWith the developments in vascular ultrasound technology, the opportunity has arisen to examine in greater detail the distribution and behavior of the perforators in normal lower limbs and the implications in understanding their normal role. MethodsThe lower limbs of 20 healthy participants free of any cardiovascular or venous disease were examined. The anatomical characteristics and distribution as well as the functional features of all ultrasound-detectable lower limb venous perforators were evaluated in these normal limbs. Perforator flow was tested at rest, supine, sitting, standing, and with exercise. Comparisons were made between standard augmentation and isometric foot plantar flexion. ResultsTwenty individuals (13 females, 7 males; mean age, 36.9 ± 12 years) participated in the study. On average each limb had 14.2 (range, 8-21) perforators identified by ultrasound examination, with an average size of 1.3 ± 0.56 mm (range, 0.4-3.5 mm), most in the medial calf and those in the lower third were larger. On ultrasound examination, the valves were observed only within these larger direct perforators (17%; 18/105). All maneuvers resulted in flow which was only from superficial to the deep system and no two-way flow was observed. Spontaneous flow at rest occurred in a small proportion, but treadmill walking led to the recruitment of most perforators with spontaneous pulsatile flow at greatly increased velocities. The estimated total perforator volume flow could be increased by up to five-fold and accounting for as much as 80 mL/min in a leg. Isometric foot plantar flexion stopped any spontaneous flow and, on relaxation, resulted in a reproduceable short burst of inflow in the calf perforators. Augmentation by calf or foot cuff compression produced a brief variable inward, flow but this flow did not correlate with the perforator flow, with the more physiological maneuvers of isometric foot plantar flexion and exercise. ConclusionsThis study has shown that normal perforator veins in the leg are unidirectional from superficial to deep veins. Although few perforators have spontaneous flow at rest, most are recruited with exercise to substantially increase spontaneous perforator flow secondary to the increased skin blood flow. The augmentation maneuver is not comparable with more physiological activity. These normal features should be taken into account in the assessment of the abnormal perforator.

Association between vein diameters, reflux characteristics, and clinical severity in patients with chronic venous insufficiency in Northwest China

ObjectiveOur goal was to summarize the relationship between vein diameters, reflux characteristics, and clinical severity in consecutive patients with chronic venous insufficiency (CVI) in Northwest China. MethodsWe evaluated 531 consecutive patients with CVI (249 women) who presented to the Department of Ultrasound of Xijing Hospital from September 2017 to July 2019. Reflux times and the mean diameters of the great saphenous, the small saphenous, and the calf perforator veins based on duplex ultrasound scans obtained in the standing position were recorded. Venous-specific assessment tools—the Heaviness, Achiness, Swelling, Throbbing, Itching (HASTI) score, the Venous Clinical Severity Score (VCSS), and the Clinical, Etiological, Anatomical, Pathophysiological (CEAP) class—were analyzed. Regression analysis was used to investigate the relationship between the clinical scores, vein diameters, and reflux times. A P value of less than .05 was considered statistically significant. ResultsWe analyzed 531 consecutive patients with 728 limbs. The mean age was 55.24 ± 11.38 years; the mean body mass index (BMI) was 24.75 ± 3.49 kg/m2. Three hundred thirty-four patients (62.9%) presented with unilateral limb findings and 197 (37.1%), with bilateral limb involvement. No significant changes were noted in age and BMI across CEAP classes (F = 2.322 and F = 3.917, respectively; P > .05 for both). Both the HASTI score (r2 = 0.8741; P < .001) and the VCSS (r2 = 0.9257; P < .001) correlated with the CEAP class. The HASTI score strongly correlated with the mean diameters of the great saphenous and small saphenous veins (r2 = 0.9252, r2 = 0.6304, respectively; P < .001 for both) similarly to VCSS (r2 = 0.9396, r2 = 0.7195, respectively; P < .001 for both). The HASTI score and VCSS correlated equally with the mean diameters of the calf perforator veins (r = 0.7773 and r = 0.7781, respectively; P < .001 for both). In those with C6, both great saphenous vein (F = 4.608; P < .001) and small saphenous vein reflux times (F = 14.97; P < .001) were significantly higher than those in C1. Both the HASTI score and VCSS strongly associated with the reflux times of the great saphenous (r2 = 0.7706 and r2 = 0.8181, respectively; P < .001 for both) and small saphenous veins (r2 = 0.6470 and r2 = 0.7865, respectively; P < .001 for both). ConclusionsThis analysis is one of the few epidemiologic studies of patients with CVI in Northwest China. Age and BMI did not correlate with CEAP class. Both the HASTI score and VCSS correlated strongly with the CEAP classification; vein diameters and reflux time in both the great saphenous vein and the small saphenous vein, indicating the validity of these outcome tools to venous hemodynamics and to CVI in general.

The hemodynamic impact of the bidirectional flow within calf perforators and conductive veins in varicose vein disease

The hemodynamic assessment of the bidirectional flow within calf perforators and in the conductive veins in varicose vein disease is presented. The bidirectional streaming within calf perforators is induced by the changing polarity of the systolic and diastolic pressure gradients arising during calf pump activity between the deep veins and the saphenous system of the lower leg, as documented by simultaneous pressure measurements in the posterior tibial vein and the great saphenous vein. This bidirectional flow makes the deep and superficial veins of the lower leg conjoined vessels. The vector of the bidirectional streaming in varicose vein patients is oriented inward, into the deep veins. The enlarged calf perforators are the consequence of the saphenous reflux; after elimination of saphenous reflux the diameter of calf perforators diminishes significantly. Results of venous pressure, plethysmographic and electromagnetic flow measurements rebut the still prevalent opinion that the outward flow within calf perforators is a reflux. There is an up-and-down flow in the conductive veins during calf pump activity with a prevailing systolic centripetal (orthograde) flow in the popliteal/femoral axis and a diastolic centrifugal (retrograde) flow in the incompetent great saphenous vein. The popliteal vein represents actually the drain pipe of the calf muscle pump. The ambulatory venous pressure gradient arising during the diastolic phase of the calf pump activity resembles the diastolic pressure difference between the aorta and the left ventricle.

Invited commentary on 'The hemodynamic impact of the bidirectional flow within calf perforators and conductive veins in varicose vein disease', by C Recek

Invited commentary on 'The hemodynamic impact of the bidirectional flow within calf perforators and conductive veins in varicose vein disease', by C Recek

Answers to the invited commentaries on 'The hemodynamic impact of the bidirectional flow within calf perforators and conductive veins in varicose vein disease', by C Recek

Answers to the invited commentaries on 'The hemodynamic impact of the bidirectional flow within calf perforators and conductive veins in varicose vein disease', by C Recek

Invited commentary on 'The hemodynamic impact of the bidirectional flow within calf perforators and conductive veins in varicose vein disease', by C Recek

Invited commentary on 'The hemodynamic impact of the bidirectional flow within calf perforators and conductive veins in varicose vein disease', by C Recek

Comparison of combined compression and surgery with high ligation-endovenous laser ablation-foam sclerotherapy with compression alone for active venous leg ulcers

We aimed to assess the ulcer healing time and recurrence rates after treatment with compression therapy (CT) with or without high ligation-endovenous laser ablation-foam sclerotherapy (HL-EVLA-FS) in people with active venous leg ulcers (VLUs). A retrospective cohort study was conducted with 350 patients with active VLUs treated by compression with or without HL-EVLA-FS in our hospital from 2013 to 2017. The primary outcome was the ulcer healing time; secondary outcomes were the 12-month recurrence rates, the relationship between recurrence and venous reflux, and the complications of the two treatments. In total, 193 patients (200 limbs) underwent compression plus HL-EVLA-FS, and 157 patients (177 limbs) underwent CT alone. The ulcer healing time was shorter in the compression plus HL-EVLA-FS group than in the CT alone group (Hazard Ratio [HR] for ulcer healing, 1.845 [95% CI, 1.474–2.309], P = 0.0001). The 12-month ulcer recurrence rates were significantly reduced in the compression plus HL-EVLA-FS group (HR for ulcer recurrence, 0.418 [95% CI, 0.258–0.677], P = 0.0001). Calf perforator vein reflux (CPVR) and isolated superficial venous reflux (ISVR) were risk factors for ulcer recurrence. The combined operation with CT resulted in faster healing of VLUs, a lower ulcer recurrence rate and lower VCSS values after intervention than CT alone.

LEV 2. Preliminary First in Human Ultrasound-Guided High-Intensity Focused Ultrasound Treatment in Superficial Lower Limb Veins

High-intensity focused ultrasound (HIFU) is an alternative to surgery or other thermal methods widely used in the treatment of thyroid, breast fibroadenoma, and uterine fibroma. HIFU generated by the Echopulse (Theraclion, Malakoff, France) device penetrates through tissues and causes localized hyperthermia responsible for irreversible protein denaturation and vein wall coagulation, whereas overlying and surrounding tissues are spared by focusing a beam into a given target. A focused transducer (3 MHz frequency) generates the ultrasound field. An imaging array of 7.5 MHz is centrally integrated to allow perfect alignment between the real-time imaging and the focal point. A first in human prospective study is ongoing, and patients were observed up to 3 months. We have several examples of positive results that are currently available. Most of the cases were performed without anesthesia and were well tolerated, and no severe adverse events were observed. A female patient presenting with recurrence after great saphenous vein (GSV) stripping received 12 pulses with a mean power of 45 W. No anesthesia was performed. The treated area was occluded acutely, and this result persisted at 3 months. A female patient presenting with a refluxing stump and neovascularization after GSV stripping as well as an active ulcer was treated at the groin level, over the stump and area of the neovessels. Ten pulses were delivered with a mean power of 42.9 W. No anesthesia was performed. The recurrent flow was abolished, and the ulcer was healed at 3 months. A male patient presenting with a refluxing calf perforator was treated after unsuccessful surgery and sclerotherapy. Nine pulses were delivered at a mean power of 45 W. No anesthesia was performed. The perforator was occluded acutely, and this result persisted at 3 months. A male patient presenting with a refluxing GSV and active ulcer was treated after surgery. Thirty-nine pulses were delivered with a mean power of 38 W. Tumescent anesthesia was performed. The vein was occluded acutely, and this result persisted at 3 months. The ulcer was healed at 3 months. In this first study using HIFU, the preliminary results are encouraging and show that HIFU could become a credible alternative method. In future studies, more cases and longer follow-up will be needed.

Contribution of the calf pump and foot pump to the return of venous blood from the lower extremity

The anatomy and function of the calf pump and the foot pump as well as the interplay of their activity are described. The calf muscle pump constitutes an effective mechanism enhancing efficiently the return of venous blood toward the heart. During calf muscle contractions, the venous blood is ejected mainly into the popliteal vein, but a smaller part escapes through calf perforators into the saphenous system and streams further in the centripetal, i.e. physiological direction toward the heart. Calf muscle contractions induce marked increase in systolic pressure and calf muscle relaxations entail decrease of diastolic pressure both in deep and superficial veins of the lower leg. The systolic and diastolic pressure changes are produced in deep veins and are transmitted through calf perforators into the saphenous system, as documented by simultaneous pressure recordings in the posterior tibial and great saphenous veins. The systolic increase of pressure in the great saphenous vein is caused by the outward flow within calf perforators; competent valves in calf perforators would preclude any relevant pressure increase. Calf pump activity entails a distinct decrease of ambulatory venous pressure in lower leg veins, whereas in the thigh veins the pressure does not decrease; in this way, the ambulatory pressure gradient of 37.4 +- 6.4 mm Hg arises between thigh and lower leg veins and triggers the venous reflux in incompetent venous channels connecting both poles of the ambulatory pressure gradient. In contrast to the very efficient performance of the calf pump, the performance of the foot pump is hemodynamically unimportant. The ejection volume produced by the calf muscle pump comes at about 60 ml or more, whereas the blood volume ejected by the foot pump reaches a negligible value of 3-4 ml.

Calf Perforator Flaps: A Freestyle Solution for Oral Cavity Reconstruction.

Reconstruction of oral cavity defects requires a thin, pliable flap for optimal functional results. Traditional flap choices are imperfect: the anterolateral thigh flap is excessively thick, whereas the radial forearm flap has a poor donor site. The authors therefore favor calf perforator flaps such as the medial sural artery perforator flap to provide thin tissue with an acceptable donor site. This two-part study aims to demonstrate their suitability for intraoral reconstruction. In the radiologic part of the study, the authors compared thigh and calf tissue thickness by examining lower limb computed tomographic scans of 100 legs. For their clinical study, they collected data prospectively on 20 cases of oral cavity reconstruction using calf perforator flaps. The mean thickness of the calf tissue envelope was significantly less than that of the thigh (8.4 mm compared with 17 mm) based on computed tomographic analysis. In the clinical study, a medial sural artery perforator was used in the majority of cases (17 of 20). The mean pedicle length was 10.2 cm and the mean time to raise a flap was 85 minutes. There were no flap losses. One patient was returned to the operating room for management of late hematoma and wound dehiscence. Calf perforator flaps provide ideal tissue for intraoral reconstruction and are significantly thinner than anterolateral thigh flaps. In addition to medial sural artery perforator flaps, the authors raised both sural and soleal artery perforator flaps in this series. Opportunistic use of the calf donor site allows the harvest of thin tissue with minimal donor-site morbidity. Therapeutic, IV.

Discussion: Calf Perforator Flaps: A Freestyle Solution for Oral Cavity Reconstruction

Discussion: Calf Perforator Flaps: A Freestyle Solution for Oral Cavity Reconstruction

Competent and incompetent calf perforators in primary varicose veins: a resistant myth

The pathophysiology of calf perforators is presented. Bidirectional flow within calf perforators with a prevailing inward, into deep veins oriented component arises during calf pump activity in varicose vein patients, as evidenced by venous pressure measurements, plethysmographic findings, duplex ultrasonography, and electromagnetic flow measurements. Reflux within calf perforators is an inward, not outward, flow; the opinion that the outward flow within calf perforators is a reflux is at odds with the reality. During calf muscle contraction, the pressure in the posterior tibial vein is higher than in the great saphenous vein; it induces the harmless outward flow within calf perforators, which runs further via great saphenous vein in the physiological direction toward the heart. Deep and superficial veins of the lower leg form conjoined vessels, as documented by nearly equal pressure curves registered simultaneously in the posterior tibial and great saphenous veins both in varicose vein patients and in healthy people. Calf perforators do not entail ambulatory venous hypertension or any other hemodynamic disorder, even if enlarged and incompetent; their ligation is needless. The diameter of calf perforators is influenced by the intensity of saphenous reflux; it enlarges with increasing intensity of saphenous reflux and diminishes after the abolition of reflux.

Calf perforator flaps: first choice for oral cavity reconstruction

Introduction: Calf perforator flaps are emerging as a popular choice in H&N reconstruction due to their favourable donor site morbidity. There are multiple source vessels in this region – the medial sural artery (MSAP) flap is the most commonly used. We document our clinical experience using calf perforator flaps in oral cavity reconstruction. In addition, we performed a cadaveric dissection study to determine predictability of perforator topography.

The fate of calf perforator veins after saphenous vein laser ablation.

We aimed to assess hemodynamic changes in calf perforator veins (PVs) after endovenous laser ablation (EVLA) of saphenous veins. The series comprised 60 limbs of 41 patients (27 female, 14 male; median age, 43 years [range, 22-78 years]) who underwent EVLA for varicose veins. All patients were prospectively evaluated by means of color Doppler ultrasonography before and after the procedure. EVLA did not change the rate of incompetent PVs (preoperatively, 154/483 [32%] vs. postoperatively, 167/501 [33%]; P = 0.173), but significantly increased the total number of all PVs (n=483 vs. n=501, P = 0.036). Following EVLA, 28% of the limbs had thrombosis of PVs, 34% had new US-detectable PVs, 42% showed new competency, and 52% showed new incompetency. New competent PVs were found more commonly in the medial leg (ablation site) than the lateral leg (nonablation site) (28.3% vs. 11.7%, P = 0.016), while new incompetent PVs were found more commonly in nonablation site than ablation site (31.7% vs. 18.3%, P = 0.086). Additionally, new competent PVs in the posterior leg were found more often in patients who had small saphenous vein ablation than patients who did not (30% vs. 0%, P = 0.002). EVLA induces numerous changes in calf PVs. These changes seem to result from flow offloading in ablation site and onloading in nonablation site in the early postablation period.

The haemodynamic role of calf perforators

The haemodynamic role of calf perforators

Calf pump activity influencing venous hemodynamics in the lower extremity.

Calf muscle pump is the motive force enhancing return of venous blood from the lower extremity to the heart. It causes displacement of venous blood in both vertical and horizontal directions, generates ambulatory pressure gradient between thigh and lower leg veins, and bidirectional streaming within calf perforators. Ambulatory pressure gradient triggers venous reflux in incompetent veins, which induces ambulatory venous hypertension in the lower leg and foot. Bidirectional flow in calf perforators enables quick pressure equalization between deep and superficial veins of the lower leg; the outward (into the superficial veins) oriented component of the bidirectional flow taking place during calf muscle contraction is no pathological reflux but a physiological centripetal flow streaming via great saphenous vein into the femoral vein. Calf perforators are communicating channels between both systems making them conjoined vessels; they are not involved in the generation of pathological hemodynamic situations, nor do they cause ambulatory venous hypertension. The real cause why recurrences develop has not as yet been cleared. Pressure gradient arising during calf pump activity between the femoral vein and the saphenous remnant after abolition of saphenous reflux triggers biophysical and biochemical events, which might induce recurrence. Thus, abolition of saphenous reflux removes the hemodynamic disturbance, but at the same time it generates precondition for reflux recurrence and for the comeback of the previous pathological situation; this chain of events has been called hemodynamic paradox.

Images in vascular medicine

A 10-year-old male presented with right calf painful swelling 2 years after he accidentally hit his right calf against a wrought-iron bed railing. A localized bruise and edema progressed in size along with symptoms over the past 2 years. At presentation, the swelling measured 51 mm (Panel A). Certain movements, such as dorsiflexion and running, exacerbated his symptoms. Vascular surgery and interventional radiology at an outside facility diagnosed cavernous venous malformation and possible arteriovenous malformation, based on magnetic resonance venography and computed tomographic venogram. Venous color duplex at our institution showed right distal calf perforator (Cockett’s perforator) incompetency with varicosities (Panel B). A subsequent venogram showed prominent varicose veins without vascular malformation (Panel C). The Panel A