The Journal of Vascular Teechnology 21(3):167-172, 1997 Relationship Between Reflux and Greater Saphenous Vein Diameter C. Engelhorn, MD,A. Engelhorn, MD, S. Salles-Cunha, PhD, E Picheth, MD, N. Castro Jr, MD, N. Dabul Jr, MD, C. Gomes, MD ABSTRACT Purpose: Quantitative algorithms to select patients for stripping, ligation, or banding require additionaldataongreatersaphenousvein(GSV)diameterandvalvularfunction.Althoughthefinalgoalisto determine whether reverse flow, or reflux, is due to valvular damage, valvular absence, or vein enlargement with normal valves, this study was a first step in quantifying the influence of venous enlargement as a potential cause of reflux. Methods: Color flow ultrasound venous evaluation was performed in 100 extremities of 65 women and 14 men with primary varicose veins. Greater saphenous vein diameters measured at the junction with the common femoral vein, in the thigh, and in the calf were compared for two groups: veins with significant reflux (defined as peak reflux velocity >30 cm/sec or duration >0.5 sec) and veins without significant reflux. Accuracy and positive (PPV) and negative (NPV) predictive values for reflux were calculated for 1 mm diameter increments. Results: Differences in diameters of veins with significantrefluxversusveinswithoutreflux,7.7+-2.3(SD)mm(n=46)versus5.7+-1.3mm(n=54)atthe junction,5.5+-2.0mm(n=57)versus3.3+-1.2mm(n=43)inthethighand3.5+-1.4mm(n=41)versus2.5 +- 0.6 mm (n=59) in the calf, were statistically significantly different (p=0.000, t-test). Best accuracies for predicting reflux at the junction, thigh, and calf, 71, 75, and 74%, respectively, were achieved with diameter thresholdsequaltoorgreaterthan7,4,and4mmwithcorrespondingPPVof73,81,and89%andNPVof70, 69and70%.Fordiametersequaltoorgreaterthan9,7,and5mmatthejunction,thigh,andcalf,respectively, PPV=100% were achieved. Conclusions: Saphenous vein diameter was a significant factor in valvular insufficiency with significant reflux. In a mixed population, a single diameter criterion accurately predicted reflux in about 70% of the extremities. Diameter thresholds with probable certainty to cause reflux were found.Thesefindingsmayinfluenceselectionoftreatmentalternatives. morbidity,andimprovedvenousfunction. Quantitativealgorithmstoselectpatientsforsaphenectomy, ligation, or banding require additional data saphenous vein diameter and valvular function. General goals for this research program are: (1) to develop algorithms associating reverse flow, or reflux, to valvular damage, valvular absence, or vein enlargement with normal valves and (2) to develop criteriaforexclusionofsourcesofrefluxwhilepreservingthe saphenousvein.Withtheseobjectivesinmind,thisstudywas a first step toward quantifying the influence of large venous diameters as a potential cause of reflux in a population concerned with the cosmetic appearance of their lower extremities. Introduction The surgical treatment for varicose veins has been changing significantly in recent years. Surgeons and patients have concerns about cosmetic results and saphenous preservation for future cardiac or peripheral arterial bypasses. The availability of noninvasive techniques in general and color flow duplex ultrasonography have permitted anatomical and functional evaluation of the deep, communicating, and superficial venous systems. Selective surgery, individualized for eachpatient,isnowpossiblewithavoidanceofunnecessary saphenous vein stripping. The greater saphenous vein can be preserved entirely or segmentally. This approach may have a long-term benefit of bypass conduit availability. Immediate benefits of this simplified surgical procedure, however, are less trauma, decreased postoperative 1-4 Methods PatientPopulation Color flow ultrasound evaluation of the superficial veins was performed in 100 extremities of 79 patients. There were 65 women and 14 men. The mean age was 30 years (18-64 = range). From the Pontifícia Universidade Católica do Paraná, Curitiba, PR, Brazil. Address correspondence to: Sergio Salles-Cunha, Ph-D, Jobst Vascular Center, 2109 Hughes Dr., Suite 400, Toledo, OH 43606.
JVT 21(3) ENGELHORN ETAL. 168 All patients were referred to the vascular laboratory for preoperative assessment prior to varicose vein surgery. None had clinical signs of deep venous thrombosis or leg ulcers. were evaluated as reflux sources in the calf. Reflux patterns aredescribedintheAppendix. Statistics . GSV average diameters (1) at the Group differences DiameterMeasurements junction with the common femoral vein, (2) in the thigh, and (3) in the calf were compared for two groups: Group I, veins with significant reflux, and Group II, veins without significant reflux.Averages were compared using a Student's t-test. All patients were evaluated with color flow duplex ultrasoundinawarmroom,usuallyattheendofaworkday. With the patient supine, a 5-MHZ transducer was used to ruleoutchronicorrecentdeepvenousthrombosis.Withthe patient standing, a 7-MHZ transducer was used to measure greater saphenous vein (GSV) diameters. Measurements were performed in cross-sectional B-mode images at different levels: sapheno-femoral junction at the groin; upper, mid-, and distal thigh; knee; and upper, mid-, and distal calf.Thigh and calf measurements were averaged for analysis. RefluxDetection Using color flow imaging in the longitudinal view, the saphenous valvular function was evaluated at the femoral junction, thigh, and calf levels. Flow direction was noted duringValsalvamaneuverandproximalanddistalmuscular compressions. Reflux was quantified based on maximum reversevelocityand/orvalveclosuretimefromtheDoppler spectral tracings obtained in longitudinal section. Reflux was considered significant if peak velocity greater than 30 cm/sec or a valve closure time greater than 0.5 sec was detected. Sourcesofrefluxroutinelyexaminedinthegroin were the sapheno-femoral junction, pelvic veins, and greater saphenous accessories and tributaries. In the thigh, saphenous accessories, tributaries, and perforating veins, primarily Dodd's and Hunter's, were investigated as potentialsourcesofreflux.Branchesfromlessersaphenous vein and perforating veins, primarily Cockett's and Boyd's, 4-5
169 1997 REFLUXAND GREATER SAPHENOUS VEIN DIAMETER . Probability of reflux given by Reflux prediction decreased by 2 mm from the junction to the thigh and then from the thigh to the calf.At the junction and the thigh, veins with reflux were 2 mm larger in diameter than veins without reflux. At the calf level, the difference in diameter between veins with and without reflux was less, 1 mm. These differenceswerestatisticallysignificantbyt-test. Accuracies to predict reflux based on GSV diameters are depicted in Figures 1-3. At the junction, a 7-mm diameter threshold had the best accuracy (71%) for predicting reflux (equal to or greater than 7 mm had reflux, less than 7 mm correspondingtonoreflux).Inthethigh,thebestaccuracyfor predictive accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated as a function of GSV diameters at the femoral junction, thigh, andcalflevels. Results Table I lists the average GSV diameters as a function of reflux.Greatersaphenousveindiametersrangedfrom2.7to 14.0mmatthefemoraljunction,1.5to12.0mminthethigh, and 1.3 to 8.0 mm in the calf. On average, GSV diameters
JVT 21(3) ENGELHORN ETAL. 170 predicting reflux (75%) was achieved with a 4-mm diameter threshold.Inthecalf,a4mm-diameterthresholdalsogavethe bestaccuracyforpredictingreflux(74%).Thecorresponding PPV for the 7-mm threshold at the junction and 4-mm thresholds at the thigh and calf were 73, 81, and 89%, respectively, and the NPV were 70, 69, and 70% for veins smallerthanthesethresholds. PositiveandnegativepredictivevaluesareshowninFigures 4-6 and 7-9.At the junction, all veins with 9 mm or more had reflux (n = 10).At this level, 18 of 22 veins with less than 5- mm diameter had no reflux. In the thigh, all 14 veins with diameters equal to or greater than 7 mm had reflux. The majorityofveinswithlessthan3-mmdiameter(17of20)did not have reflux. In the calf, almost all veins with diameters of 4mmormorehadreflux(17/19).Withoneexception(13/14), veinswithlessthan2-mmdiameterhadnoreflux. Discussion Varicose vein surgery has grown, with great demands for excellent cosmetic results. Because the saphenous vein is often treated in conjunction with varicectomy, informed patients have inquired about the saphenous vein value as a conduit for cardiac or peripheral bypasses. Besides leg appearance or future bypasses, we now have a growing awareness of functional or clinical outcome after treatment, and remaining saphenous vein segments may benefit venous function. These concerns have led to increased saphenous veinpreservationinconnectionwithvaricoseveintreatment. Thesaphenousveincanbepreservedtotallyorsegmentally. Saphenous vein banding or ligation at the femoral junction hasbeenperformedsuccessfully. Ifthesourcesanddrainages of reflux are complex (see Appendix), individual surgery is planned accordingly. It is beyond the scope of this paper to discuss treatment algorithms in detail. Treatment options, however, have been selected empirically. We have yet to define quantitative methods to determine, for example, if banding or ligation will be successful in eliminating reflux or in reducing vein diameter. Which of these two goals is more important? This is an important question without a quantitative answer. We still must investigate differences between residual or recurrent reflux after treatment and welcome reverse flow that maintains the saphenous vein intact.Itisalsofundamentaltoseparateconditionsofvalvular damage from venous enlargement as a cause of reflux. As a first step in this quantification process, we investigated the relationship between diameter and reflux observed preoperatively. An important technical consideration is that venous enlargement with daily activities and standing may cause reflux. In normal veins of young, healthy subjects, daily activities may not affect valvular function significantly. As venous elasticity degenerates, however, reflux appearance may follow conditions affecting venodilation. The patients included in this study were evaluated under conditions favoring the occurrence of reflux. Exercise, a warm environment, and standing favor venodilation. Greater saphenous vein diameters measured were compatible with literature data measured in similar conditions. These values may be slightly larger than values obtained during saphenous veinmappinginsearchforinfrainguinalbypassconduits. 6 7 7 8-14 .
171 1997 REFLUXAND GREATER SAPHENOUS VEIN DIAMETER That reflux would be more frequent in large veins is common knowledge. This numerical analysis quantified such a general concept. For example, based on the average diameter difference for the two groups, with and without reflux, a 2-mm dilation of the veins could cause reflux. Conversely, it should be possible to eliminate reflux if venous compression with stockings or venous banding reducedthediameterby2mm. We also have determined that certain specific diameter thresholds, 9 mm at the junction, 7 mm in the thigh, and 5 mm in the calf, are markers for certainty of reflux. A question yet to be answered is whether such large veins are damaged and therefore inadequate for cardiac or peripheral bypasses. Another question to be considered is whether banding or ligation can decrease such large diameters significantlytoimprovepatientwellbeing.. On the other side of the spectrum, minimum diameters correlatewithlackofreflux,particularlydiameterslessthan 5 mm at the femoral junction and less than 3 mm in the thigh. These veins ought to be preserved. In the calf, it has become apparent that reflux is a more complex issue. In the midrange of diameters, reflux is relatively unrelated to diameterandindividualevaluationhelpsdirecttreatment. In summary, venous diameter is significantly related to reflux, as expected. We obtained specific large diameters thatareassociatedwithaveryhighprobabilityofreflux.We also determined specific small diameters associated with virtual lack of reflux, particularly at the femoral junction and thigh. Finally, the effect of therapy on venous diameter must be evaluated to create quantitative algorithms for saphenous vein preservation, either for arterial bypass or improved venous function, and to better understand the differencesbetweenvalvedamageorvalvedysfunctiondue tovenousdilation. 6 preservation of the saphenous vein: A comparison between high ligation-avulsion versus saphenofemoral bandind valvuloplasty-avulsion.JVascSurg20:684-687,1994. 7 Criado E, Daniel PF, Marston W, et al.: Physiologic variations in lower extremity venous valvular function. Ann VascSurg9:102-108,1995. 8 Hanna LJ, Stedge KJ, Skorcz MJ, et al.: Mapping of the greatersaphenousveinpriortoinsitugraftingusingrealtime B-modeultrasound.Bruit9:70,1985. 9 Fitzgerald KM, Kupinski AM, Kay C, et al.: B-mode ultrasoundveinmapping.JVascTechnol12:63-66,1988. 10 BerrySM,SusmanB,IbrahimIM,etal.:Determinationof “good” saphenous veins for use in situ bypass grafts by real timeB-modeimaging.JVascTechnol12:184-189,1988. 11 Bagi P, Schroeder T, Sillisen H, et al.: Real-time B-mode mappingofthegreatersaphenousvein.EurJVasc3:103-105, 1989. 12 FligelstoneL,CarolanG,PughN,etal.:Anassessmentof thelongsaphenousveinforpotentialuseasavascularconduit aftervaricoseveinsurgery.JVascSurg18:836-840,1993. 13 Rizzo JL, Baker LA, Boyajian RA, et al.:Accuracy of B- modeultrasoundveinmappingforvesselsize.JVascTechnol 17:287-289,1993. 14 Blebea J, Schomaker WR, Hod G, et al.: Preoperative duplex venous mapping: A comparison of positional techniques in patients with and without arteriosclerosis. J VascSurg21:226-234,1994. Schanzer H, Skladany M: Varicose vein surgery with Appendix References Greater Saphenous Vein (GSV): Reflux Patterns Reflux source None GSV: none Tributaries Femoral junction branches Femoral junction (GSV) Type 0 I Reflux drainage None GSV: none Tributaries 1 Talbot SR: Use of real-time imaging in identifying deep venous obstruction: A preliminary report. Bruit 6:41-42, 1982. 2 Salles-Cunha SX, Beebe HG: Direct noninvasive tests (duplex scan) for evaluation of acute venous disease. In: Gloviczki P,Yao JST(eds): Handbook of venous disorders. Guidelines of the American Venous Forum. London: ChapmanandHallMedical,pp112-129,1996. 3 Engelhorn C, Picheth F, Castro N, et al.: Color flow localization of insufficient communicating or perforating veins prior to surgical ligation. J Vasc Technol 17:251-253, 1993. 4 Summer DS. Direct noninvasive tests for the evaluation of chronic venous obstruction and valvular incompetence. In: Gloviczki P, Yao JST (eds): Handbook of venous disorders. Guidelines of the American Venous Forum. London:ChapmanandHallMedical,pp130-151,1996. 5 Van Bemelen PS, Beach K, et al.: The mechanism of venous valve closure. Its relationship to the velocity of reverseflow.ArchSurg125:617-619,1990. II Varicose branches Perforating veins Distal GSV with reflux III Perforating vein Varicose branch Perforating vein Varicose branch Diffuse GSV reflux IV Perforating vein Varicose branch Diffuse V In types 0 and I, the GSVis not involved; in type II, GSVhas reflux only proximally; in type III, GSV has reflux only distally; in type IV, GSV has reflux segmentally; and in type V,theentireGSVisinvolved.