Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Variations in Lower Limb Deep Venous Anatomy in Latvia

Variations in Lower Limb Deep Venous Anatomy in Latvia 10.2478/chilat-2013-0010 ORIGINAL ARTICLE Dainis Krievins *, ***, Regina Zarina R, ***, Janis Savlovskis **, ***,*, Polina Dombure *, **** * Department of Vascular Surgery, Pauls Stradins Clinical University Hospital, Riga, Latvia ** Department of Radiology, Pauls Stradins Clinical University Hospital, Riga, Latvia *** University of Latvia, Riga, Latvia **** Riga Stradins University, Riga, Latvia Summary Introduction. During the last several decades there have been many new methods introduced for the treatment of lower limb chronic venous insufficiency (laser, foam, subendothelial and thermal coagulation methods). Venous system of lower limbs often presents anatomic variations including venous duplications. Knowledge of venous system variations in the lower limb area is of particular importance due to correct interpretation of imaging in relation to deep vein thrombosis (DVT). There was only a small number of studies published on anatomic variations of venous system in the lower limbs. To the best of our knowledge there have been no previous studies on anatomic variations of lower limb deep venous system performed in Latvia. Aim of the study. To retrospectively review of 216 patients (432 lower limbs) phlebograms in order to establish deep venous system anatomic variations in Latvian population and compare our results to other publications. Materials and methods. Retrospective analysis of 432 lower limb phlebograms performed at Pauls Stradins Clinical University Hospital (Riga, Latvia) of 216 patients treated in different ortopedic centers of Latvia during 2009 and 2012. Assessment made using DICOM Synedra view personal software. Study protocol was developed for definition of veins and assessment of phlebogram images in accordance with anatomic definitions used in previous studies. Two independent radiologists assessed data. Visualised duplications in the deep venous system of both lower limbs in patients were registered (common iliac vein, external iliac vein, common femoral vein, femoral vein, deep femoral vein, popliteal vein). Blood vessels have been listed as single, double or triple / complex. The presence of DVT was recorded upon assessment of phlebograms. Statistical analysis performed using SPSS 20.0 software (IBM). Parametric data comparison performed using Student t-test and ANOVA. Non-parametric data comparison performed using chi-square and Mann Whitney tests. Data comparison type was assessed using Kolmogorova-Smirnovs test. The results are presented as the average ± standard deviation. Results. Retrospective analysis of 432 lower limb phlebograms was performed in 216 patients. Average age of the patients was 34.4 years (range 19-90). 101 patients were female (47%) and 115 (53%) were male with no statistical venous variation differences found between two genders, which is explained by both age and gender (p > 0.05). Analysis of calf vein, popliteal vein and femoral venous variations provided a strong correlation between larger number of duplications in one limb and possibility of such variations in the other limb of the same patient (all p < 0.001). Conclusion. We conclude that there are frequent anatomic variations in SFV and popliteal veins seen in Latvian population. All patients included in this study had high DVT risk, much higher than in the average Latvian population. In almost every sixth Latvian person there is some form of deep veins hypoplasia found. Keywords: venous anatomy; deep veins; femoral vein; popliteal vein; calf veins; venography. INTRODUCTION Up to 73% of women and 53% of men worldwide are diagnosed with chronic venous insufficiency (CVI). In Europe over one third of population is diagnosed with CVI, 40-60% of females and 15-30% of males (5). Furthermore, deep venous thrombosis (DVT) occurs for the first time in about 100 persons per 100 000 each year (6). Precise diagnosis and proper treatment reduce morbidity and mortality from DVT. Therefore it is essential to understand the normal anatomy of lower limb venous system in order to establish correct diagnosis and provide treatment. There are frequent variations found in deep veins of lower limbs. Duplications of femoral veins may be one of the potential reasons for wrong DVT diagnosis. The significance of lower limb normal venous anatomy and its variations was determined in line with the development of minimally invasive surgical interventions methods for the treatment of lower limb chronic venous insufficiency (laser, foam, subendothelial and thermal coagulation methods). The understanding of lower limb normal anatomy changes is important in order to prevent unforeseen complications in this region during intervention. Veins serve as the best material for arterial grafting and therefore the understanding of deep and superficial veins condition is especially important. Apart from that sometimes the duplication of femoral vein is used in arterial reconstructions if large saphenous vein is not available. There is a small number of studies published on anatomic variations in venous system. Quinlan et al report that the incidence of femoral veins' duplications is approximately 20-25%, however this incidence could be higher if also partial duplications were taken into account (5). Until now there have been no studies on lower limb deep venous system anatomic variations performed in Latvia. The aim of this study was retrospective analysis of lower limb deep venous system variations in Latvia and comparison of results to published data on other populations. MATERIALS AND METHODS Retrospective analysis of lower limb phlebograms in 216 patients (432 limbs) was performed. Phlebographies were performed in the period between 2009 and 2012 in Pauls Stradins Clinical University Hospital (Riga, Latvia). All patients have undergone hip or knee endoprosthetic replacement and received prophylactic anticoagulant therapy in different ortopedic clinics in Latvia. The subiect group represents unselected patients proportionally coming from all regions in Latvia. Phlebography was performed in order to exclude DVT, which is an often complication after joint replacement surgery. Phlebograms of 15 patients have been excluded from the study due to poor imaging quality preventing from assessing venous anatomy. Phlebograms were assessed using DICOM Synedra view personal software. Prior to commencing the study there was a study protocol developed for definition of veins and assessment of phlebogram images in accordance with anatomic definitions used in previous studies. Two independent radiologists assessed data. In case of discordance of the results between them, patient was re-evaluated and final conclusion made. Visualised duplications in the deep venous system of both lower limbs in patients was registered (common iliac vein, external iliac vein, common femoral vein, femoral vein, deep femoral vein, popliteal vein). Blood vessels have been listed as single, double or triple / complex. In-flow point (junction) of every limb's vein into the calf or popliteal vein and the location of this junction with respect to other vessels was marked. Using this information the classification was made defined as calf's veins join in trifurcation before creating a popliteal vein. Hypoplasticity of calf's deep veins was also marked. Hypoplastic veins were defined as those with diameter <50% from other calf's deep veins diameter. Number of vessels in popliteal fossa have been assessed and counted, including those vessels crossing the knee joint. Using popliteal fossa as the landmark, the location of popliteal vein creation was recorded. Duplications and `true' duplication of popliteal vein were recorded. The `true' popliteal vein duplication is when popliteal vein commences and finishes in the popliteal fossa region. Popliteal vein was classified as single, double or triple. Femoral vein (FV) was registered as single, double or triple /complex. Special attention was paid to analysis of deep femoral vein and large saphenous vein in order to avoid wrong interpretation of the aforesaid veins as FV. FV duplications were assed at the point of their origin, position, length and size with respect to the original FV that was defined as the vessel that most closely followed the course of the superficial femoral artery. Position of FV duplication was registered as medial or lateral against the true FV, or both, if such duplications were from both sides of the true FV. Lengths of FV duplications were divided into the following length groups: 1-5 cm, 6-10 cm, 11-20 cm, 21-30 cm and 31 cm or larger. In addition to that the level of lowest duplication point was recorded: above or in adductor channel region, above or under patella. Each direct FV and deep femoral vein junctions with distal anastomoses have been recorded. The presence of DVT was recorded upon assessment of phlebograms. Statistical analysis performed using SPSS 20.0 software (IBM). Parametric data comparison performed using Student t-test and ANOVA. Non-parametric data comparison performed using chi-square and Mann Whitney tests. Data comparison type was assessed using Kolmogorova-Smirnovs test. The results are presented as the average ± standard deviation. RESULTS Retrospective analysis of 432 lower limb phlebograms was performed in 216 patients. Average age of the patients was 34.4 years (range 19-90). Out of all patients 101 patients were female (47%) and 115 (53%) were male with no statistical venous variation differences found between two genders, which is explained by both age and gender (p > 0.05). Analysis of calf vein, popliteal vein and femoral venous variations provided a strong correlation between larger number of duplications in one limb and possibility of such variations in the other limb of the same patient (all p < 0.001). The majority of anterior tibial veins and posterior tibial veins and peroneal veins were paired ­ respectively: 71% (307 and 432), 90% (388 and 432) and 89% (384 and 432). Single veins were seen in 26% (111 our of 432), 9% (39 out of 432) and 5% (23 out of 432) cases respectively. Three or more peroneal veins were found in 6% (25 out of 432), part of anterior tibial veins in 3% (14 out of 432), posterior tibial veins in 1% (5 out of 432) patients. Drainage of the peroneal veins into the trifurcation occurred in 67% (288 out of 432) of cases; into the posterior tibial vein in 25% (110 out of 432) cases and into anterior tibial veins in 8% (34 out of 432) cases respectively. Gastrocnemius vein were only visible in 60% (259 out of 432) cases, and 78% (202 out of 259) cases the drainage was above the knee joint. A variable number of gastrocnemius veins (one to six) were visualised. In the venous system of the calf 18% (79 out of 432 lower limbs) of veins were hypoplastic. Out of these 11% (49 out of 432 lower limbs) had hypoplastic anterior tibial veins, 6% (27 out of 432 lower limbs) posterior tibial veins and 0.7% (3 out of 432 lower limbs) peroneal veins. The incidence of hypoplastic veins did not differ between right and left limbs, between gender and age of the patients (all p>0.05). In neither of the limbs we have visualised venous agenesis. Most frequently (49 out of 79 hypoplastic veins) anterior tibial vein hypoplasticity was diagnosed. However hypoplastic peroneal veins were visualised only in three patients (Table 1 and 2). Data on popliteal vein are presented in Table 3. In total there have been 51% (220 out of 432 limbs) popliteal vein true and false duplications visualised. Out of these 176 were duplications, whereas five triple or complex. Jointly 181 (42%) popliteal vein duplications were diagnosed, out of which true duplications recorded in 39 (9%) out of 432 lower limbs. The length of duplicated popliteal vein in both limbs was ranging from 6.0 up to almost more than 8.9 cm with average length being 7.5±6.9 cm. Length of duplications in the right and left limb as well as intra-gender differences have been significantly different (p<0.05). The origin of popliteal vein at popliteal fossa level was found in only six (1%) of patients' limbs, proximally from fossa in 269 (62%) of cases and distally from the knee joint in 157 (36%) out of 432 lower limbs. Within a popliteal fossa a single vessel was identified in 47 (11%) of phlebograms, two vessels in 307 (71%) phlebograms, three or more vessels in 78 (18%) out of 432 lower limbs. The incidence of popliteal veins did not differ between patients' age and gender (p>0.05). However there was a statistically significant incidence of true popliteal vein duplication found between patients' age and gender (p<0.05). Full details provided in Table 4. FV duplications were found in 188 (43%) out of 432 limbs, out of which the majority 38% (166 out of 188) were double (Figure 1b). The remaining 5% (22 out of 432) had more complex venous system. Complex femoral veins provided in Figure 1a. Medial duplications (Figure 2a) found in 120 (63%) of 188 duplicated vessels, out of which 74 (39%) originated in the middle of the thigh (above adductor channel) and 68 (36%) originated in the adductor channel area. The length of duplicated femoral veins in both limbs differed from 1 up to more than 30 cm, with average length 14.9 ± 6.1 cm (standard deviation): 13.5 ± 6.0 cm duplicated and 16.5 ± 7.4 cm complex duplicated veins. More details can be found in Tables 4 and 5. In cases of complex venous segment (triple/complex) these were longer than double veins (p < 0.05 in both limbs). In comparison to duplications, complex veins were located in adductor channel projection (p < 0.05 for both limbs). Out of 188 femoral veins duplications 122 (65%) femoral vein diameters were smaller than one third of the main femoral vein, but 53 (28%) were half the diameter. In only small number of cases, that is 13 out of 188 (7%) was the duplicated FV the same size. Most frequently in 32% of cases (130 out of 432 limbs) there was FV seen without duplication with popliteal vein originating from the knee joint level (Figure 3a). Out of FV duplication types 19% (83 out of 432 limbs) FV duplications were found with popliteal veins originating proximally from the knee joint. Most frequently found popliteal vein variations were true duplications (5%) originating and ending in popliteal fossa region (Figure 3.O). Axial transformation of FV (Figure 2b) was found in 22% (95 out of 432 limbs) cases. No duplications were found in common iliac veins and deep femoral veins. However in three (0.7%) patient limbs external iliac vein duplications were found. All three external iliac vein duplications were located in the right limb. Common femoral vein duplications were found in 11 (3.5%) cases in both limbs. Seven duplications were located in the right limb and four in the left limb (Tables 6 and 7). On comparison of common femoral vein duplications between right and left patient limbs it was found that the incidence of common femoral vein duplications is significantly different between two limbs (p=0.008). Upon assessment of phlebograms DVT was found in 6% (24 out of 432) cases. Right limbs of the patients had DVT in 11 (5%) of phlebograms analysed and left limbs had DVT in 13 phlebograms (6%). No significant difference found between in gender prevalence (p=0.266) (Table 6). DISCUSSION There was a significant range in the length of duplicated veins. The lengths of duplications did not differ on average in terms of the size, both on comparison of patients' limbs and gender differences. Only popliteal vein short duplications lengths have shown significant differences on comparison between genders and right and left limbs. In our study the dominant limb of the patient was the left limb, which was found to have significant differences in longer duplications. Similar findings were published in the study of Park et al. Hypoplastic calf veins were found comparatively more often (18%). We compared the studies of Eifert and their findings have significantly differed from our results, where 392 patients were studied and 8% of calf veins were found to be hypoplastic. This study has included patients with already diagnosed congenital vascular malformations (1). Data provided by our study also differs from Quinlan et al results (5), where they report the majority (65%) of cases in popliteal vein duplications lengths to originate distally from the knee joint. In our study we found that in 62% of cases popliteal vein was originating proximally from the knee joint, which is similar to the findings of Park et al (5). Such differences could again be explained by different study methodology, where, for example, Quinlan et al study analysed only the phlebograms of the patients participating in enoxaparin study (MEDENOX) (5). All patients with a history of DVT were excluded from the study. In the study of Park et al the analysis of venous system was performed using computer tomography images and not phlebograms. This study included patients with varicose veins complications and the analysis was made based on perioperative imaging studies (4). An important hypothesis is whether duplication is a separate DVT risk factor. In our study in non-duplicated limbs there have been only 6% (24 out of 432) DVT cases recorded. This number is different from the previously published data of other authors. Liu et al study has recorded DVT in 19% of patients (3). In our study and also other published studies the hypothesis of increased DVT risk at auxiliary diagnosed duplications was not confirmed. Different methodology of our study could have influenced this result. In the study performed by Liu et al there were patients with high DVT risk analysed however symptomatic DVT patients were not excluded from the study (3). As a bias for the study authors should point out fact, that all patients included in this study had high DVT risk, much higher than in the average Latvian population due to orthopaedic surgery they underwent (7). CONCLUSIONS We conclude that there are frequent anatomic variations in FV and popliteal veins seen in Latvian population. In almost every sixth Latvian person there is some form of deep veins hypoplasia found. Conflict of interest: None REFERENCES 1. Eifert S, Villavicencio JL, Kao TC, Taute BM, Rich NM. Prevalence of deep venous anomalies in congenital vascular malformations of venous predominance // J Vasc Surg, 2000 Mar; 31(3):46271. 2. Evans CJ, Fowkes FG, Ruckley CV, Lee AJ. Prevalence of varicose veins and chronic venous insufficiency in men and women in the general population: Edinburgh Vein Study// J Epidemiol Community Health, 1999; 53:149­153. 3. Liu GC, Ferris EJ, Reifsteck JR, Baker ME. Effect of anatomic variations on deep venous thrombosis of the lower extremity // AJR Am J Roentgenol, 1986; 146:845­848. 4. Park EA, Chung JW, Lee W, Yin YH, Ha J, Kim SJ, Park SH. Three-Dimensional Evaluation of the Anatomic Variations of the Femoral Vein and Popliteal Vein in Relation to the Accompanying Artery by Using CT Venography // Korean J Radiol, 2011 May-Jun; 12(3): 327­340. 5. Quinlan DJ, Alikhan R, Gishen P, Sidhu PS. Variations in Lower Limb Venous Anatomy: Implications for US Diagnosis of Deep Vein Thrombosis // Radiology, 2003; 228:443­448 6. White RH. Epidemiology of Venous Thromboembolism // Circulation, 2003; 107 (23) I­3. 7. Paiement GD, Mendelsohn C. The risk of venous thrombembolism in the orthopedic patient: epidemiological and physiological data // Orthopedics, 1997; 20 Suppl:7-9. Table 1. Comparison of hypoplastic deep veins in the right and left calf of patients Hypoplastic Vein Right Limb 20 12 2 34 Left Limb 29 15 1 45 Both Limbs (n = 432) 49 (11%); p>0.05 27 (6%); p>0.05 3 (0,7%); p>0.05 79 (18%); p>0.05 Anterior tibial veins Posterior tibial veins Peroneal veins Total Table 2. Incidence of hypoplastic calf veins in different genders Hypoplastic vein Anterior tibial veins Posterior tibial veins Peroneal veins Total Females 21 13 1 35 Males 28 14 2 44 Total (n=432) 49 (11%); p > 0.05 27 (6%); p > 0.05 3 (0,7%); p > 0.05 79 (18%); p > 0.05 Table 3. Origin of popliteal vein and number of vessels in popliteal fossa Origin of popliteal vein At knee joint level Proximally from knee joint Distally from knee joint Number of vessels in popliteal fossa region Single Double Three or more 6 (1%) p>0.05 269 (62%) p>0.05 157 (36%) p>0.05 47 (11%); p>0.05 307 (71%); p>0.05 78 (18%); p>0.05 39 (9%); p<0.05 Address: Regina Zarina University of Latvia 13 Pilsonu Street, LV-1002, Riga, Latvia Email: regina_zarina@inbox.lv True popliteal vein duplication Table 4. Average length of FV and popliteal vein duplications in different limbs Length of duplications (cm) Popliteal vein duplication True popliteal vein duplication FV duplication True FV duplication Right Limb 7.4 ± 0.7 3.2 ± 0.5 14.3 ± 6.1 19.1 ± 6.4 Left Limb 7.6 ± 0.7 4.2 ± 0.8 13.6 ± 6.2 16.0 ± 6.5 Both Limbs (n = 432) 7.5 ± 0.7; p > 0.05 4.0 ± 0.6; p < 0.05 13.5 ± 6.0; p > 0.05 16.5 ± 7.4; p < 0.05 Table 6. Incidence of deep vein duplications in different limbs Duplication Common iliac vein External iliac vein Common femoral vein Femoral vein Deep femoral vein Popliteal vein True popliteal vein duplication Right Limb 0 3 7 94 0 88 17 Left Limb 0 0 4 94 0 93 22 0 3 (0.7%); p < 0.05 11 (2.5%); p < 0.05 188 (43.5%); p > 0.05 0 181 (42%); p > 0.05 39 (9%); p < 0.05 Both Limbs (n=432) Table 5. Position, length and lowest point of FV duplication FV Position Medial Lateral Both Length (cm) 1-5 6-10 11-20 21-30 >30 Lowest point Under patella Above patella In adductor channel Above adductor channel 2 26 25 40 1 17 43 34 3 (2%); p > 0.05 43 (23%); p > 0.05 68 (36%); p < 0.05 74 (39%); p < 0.05 4 22 52 15 1 6 31 44 12 1 10 (5%); p > 0.05 53 (28%); p > 0.05 96 (51%); p > 0.05 27 (14%); p > 0.05 2 (1%); p > 0.05 53 32 9 59 33 3 120 (63%); p > 0.05 56 (30%); p > 0.05 12 (6%); p > 0.05 Right Limb Left Limb Both Limbs Table 7. Duplications of deep veins in different genders Duplications Common iliac vein External iliac vein Common femoral vein Femoral vein Deep femoral vein Popliteal vein True popliteal vein duplication Females 0 2 7 Males 0 1 4 Total (n=432) 0 3 (0.7%); p > 0.05 11 (2.5%); p < 0.05 188 (43.5%); p > 0.05 0 181 (42%); p > 0.05 39 (9%); p < 0.05 Table 8. Isolated FV duplications and DVT a) b) Fig. 2. a) Medial duplication of FV; b) Axial transformation of deep femoral vein and duplication of FV a) b) Fig. 3: Variations in deep femoro-popliteal veins (adopted from Park et al, 2011) (4) Fig. 1. a) Complex femoral vein duplication; b) Simultaneous duplication of femoral and popliteal veins http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Acta Chirurgica Latviensis de Gruyter

Variations in Lower Limb Deep Venous Anatomy in Latvia

Loading next page...
 
/lp/de-gruyter/variations-in-lower-limb-deep-venous-anatomy-in-latvia-4Kf3rlm1I0
Publisher
de Gruyter
Copyright
Copyright © 2013 by the
ISSN
1407-981X
DOI
10.2478/chilat-2013-0010
Publisher site
See Article on Publisher Site

Abstract

10.2478/chilat-2013-0010 ORIGINAL ARTICLE Dainis Krievins *, ***, Regina Zarina R, ***, Janis Savlovskis **, ***,*, Polina Dombure *, **** * Department of Vascular Surgery, Pauls Stradins Clinical University Hospital, Riga, Latvia ** Department of Radiology, Pauls Stradins Clinical University Hospital, Riga, Latvia *** University of Latvia, Riga, Latvia **** Riga Stradins University, Riga, Latvia Summary Introduction. During the last several decades there have been many new methods introduced for the treatment of lower limb chronic venous insufficiency (laser, foam, subendothelial and thermal coagulation methods). Venous system of lower limbs often presents anatomic variations including venous duplications. Knowledge of venous system variations in the lower limb area is of particular importance due to correct interpretation of imaging in relation to deep vein thrombosis (DVT). There was only a small number of studies published on anatomic variations of venous system in the lower limbs. To the best of our knowledge there have been no previous studies on anatomic variations of lower limb deep venous system performed in Latvia. Aim of the study. To retrospectively review of 216 patients (432 lower limbs) phlebograms in order to establish deep venous system anatomic variations in Latvian population and compare our results to other publications. Materials and methods. Retrospective analysis of 432 lower limb phlebograms performed at Pauls Stradins Clinical University Hospital (Riga, Latvia) of 216 patients treated in different ortopedic centers of Latvia during 2009 and 2012. Assessment made using DICOM Synedra view personal software. Study protocol was developed for definition of veins and assessment of phlebogram images in accordance with anatomic definitions used in previous studies. Two independent radiologists assessed data. Visualised duplications in the deep venous system of both lower limbs in patients were registered (common iliac vein, external iliac vein, common femoral vein, femoral vein, deep femoral vein, popliteal vein). Blood vessels have been listed as single, double or triple / complex. The presence of DVT was recorded upon assessment of phlebograms. Statistical analysis performed using SPSS 20.0 software (IBM). Parametric data comparison performed using Student t-test and ANOVA. Non-parametric data comparison performed using chi-square and Mann Whitney tests. Data comparison type was assessed using Kolmogorova-Smirnovs test. The results are presented as the average ± standard deviation. Results. Retrospective analysis of 432 lower limb phlebograms was performed in 216 patients. Average age of the patients was 34.4 years (range 19-90). 101 patients were female (47%) and 115 (53%) were male with no statistical venous variation differences found between two genders, which is explained by both age and gender (p > 0.05). Analysis of calf vein, popliteal vein and femoral venous variations provided a strong correlation between larger number of duplications in one limb and possibility of such variations in the other limb of the same patient (all p < 0.001). Conclusion. We conclude that there are frequent anatomic variations in SFV and popliteal veins seen in Latvian population. All patients included in this study had high DVT risk, much higher than in the average Latvian population. In almost every sixth Latvian person there is some form of deep veins hypoplasia found. Keywords: venous anatomy; deep veins; femoral vein; popliteal vein; calf veins; venography. INTRODUCTION Up to 73% of women and 53% of men worldwide are diagnosed with chronic venous insufficiency (CVI). In Europe over one third of population is diagnosed with CVI, 40-60% of females and 15-30% of males (5). Furthermore, deep venous thrombosis (DVT) occurs for the first time in about 100 persons per 100 000 each year (6). Precise diagnosis and proper treatment reduce morbidity and mortality from DVT. Therefore it is essential to understand the normal anatomy of lower limb venous system in order to establish correct diagnosis and provide treatment. There are frequent variations found in deep veins of lower limbs. Duplications of femoral veins may be one of the potential reasons for wrong DVT diagnosis. The significance of lower limb normal venous anatomy and its variations was determined in line with the development of minimally invasive surgical interventions methods for the treatment of lower limb chronic venous insufficiency (laser, foam, subendothelial and thermal coagulation methods). The understanding of lower limb normal anatomy changes is important in order to prevent unforeseen complications in this region during intervention. Veins serve as the best material for arterial grafting and therefore the understanding of deep and superficial veins condition is especially important. Apart from that sometimes the duplication of femoral vein is used in arterial reconstructions if large saphenous vein is not available. There is a small number of studies published on anatomic variations in venous system. Quinlan et al report that the incidence of femoral veins' duplications is approximately 20-25%, however this incidence could be higher if also partial duplications were taken into account (5). Until now there have been no studies on lower limb deep venous system anatomic variations performed in Latvia. The aim of this study was retrospective analysis of lower limb deep venous system variations in Latvia and comparison of results to published data on other populations. MATERIALS AND METHODS Retrospective analysis of lower limb phlebograms in 216 patients (432 limbs) was performed. Phlebographies were performed in the period between 2009 and 2012 in Pauls Stradins Clinical University Hospital (Riga, Latvia). All patients have undergone hip or knee endoprosthetic replacement and received prophylactic anticoagulant therapy in different ortopedic clinics in Latvia. The subiect group represents unselected patients proportionally coming from all regions in Latvia. Phlebography was performed in order to exclude DVT, which is an often complication after joint replacement surgery. Phlebograms of 15 patients have been excluded from the study due to poor imaging quality preventing from assessing venous anatomy. Phlebograms were assessed using DICOM Synedra view personal software. Prior to commencing the study there was a study protocol developed for definition of veins and assessment of phlebogram images in accordance with anatomic definitions used in previous studies. Two independent radiologists assessed data. In case of discordance of the results between them, patient was re-evaluated and final conclusion made. Visualised duplications in the deep venous system of both lower limbs in patients was registered (common iliac vein, external iliac vein, common femoral vein, femoral vein, deep femoral vein, popliteal vein). Blood vessels have been listed as single, double or triple / complex. In-flow point (junction) of every limb's vein into the calf or popliteal vein and the location of this junction with respect to other vessels was marked. Using this information the classification was made defined as calf's veins join in trifurcation before creating a popliteal vein. Hypoplasticity of calf's deep veins was also marked. Hypoplastic veins were defined as those with diameter <50% from other calf's deep veins diameter. Number of vessels in popliteal fossa have been assessed and counted, including those vessels crossing the knee joint. Using popliteal fossa as the landmark, the location of popliteal vein creation was recorded. Duplications and `true' duplication of popliteal vein were recorded. The `true' popliteal vein duplication is when popliteal vein commences and finishes in the popliteal fossa region. Popliteal vein was classified as single, double or triple. Femoral vein (FV) was registered as single, double or triple /complex. Special attention was paid to analysis of deep femoral vein and large saphenous vein in order to avoid wrong interpretation of the aforesaid veins as FV. FV duplications were assed at the point of their origin, position, length and size with respect to the original FV that was defined as the vessel that most closely followed the course of the superficial femoral artery. Position of FV duplication was registered as medial or lateral against the true FV, or both, if such duplications were from both sides of the true FV. Lengths of FV duplications were divided into the following length groups: 1-5 cm, 6-10 cm, 11-20 cm, 21-30 cm and 31 cm or larger. In addition to that the level of lowest duplication point was recorded: above or in adductor channel region, above or under patella. Each direct FV and deep femoral vein junctions with distal anastomoses have been recorded. The presence of DVT was recorded upon assessment of phlebograms. Statistical analysis performed using SPSS 20.0 software (IBM). Parametric data comparison performed using Student t-test and ANOVA. Non-parametric data comparison performed using chi-square and Mann Whitney tests. Data comparison type was assessed using Kolmogorova-Smirnovs test. The results are presented as the average ± standard deviation. RESULTS Retrospective analysis of 432 lower limb phlebograms was performed in 216 patients. Average age of the patients was 34.4 years (range 19-90). Out of all patients 101 patients were female (47%) and 115 (53%) were male with no statistical venous variation differences found between two genders, which is explained by both age and gender (p > 0.05). Analysis of calf vein, popliteal vein and femoral venous variations provided a strong correlation between larger number of duplications in one limb and possibility of such variations in the other limb of the same patient (all p < 0.001). The majority of anterior tibial veins and posterior tibial veins and peroneal veins were paired ­ respectively: 71% (307 and 432), 90% (388 and 432) and 89% (384 and 432). Single veins were seen in 26% (111 our of 432), 9% (39 out of 432) and 5% (23 out of 432) cases respectively. Three or more peroneal veins were found in 6% (25 out of 432), part of anterior tibial veins in 3% (14 out of 432), posterior tibial veins in 1% (5 out of 432) patients. Drainage of the peroneal veins into the trifurcation occurred in 67% (288 out of 432) of cases; into the posterior tibial vein in 25% (110 out of 432) cases and into anterior tibial veins in 8% (34 out of 432) cases respectively. Gastrocnemius vein were only visible in 60% (259 out of 432) cases, and 78% (202 out of 259) cases the drainage was above the knee joint. A variable number of gastrocnemius veins (one to six) were visualised. In the venous system of the calf 18% (79 out of 432 lower limbs) of veins were hypoplastic. Out of these 11% (49 out of 432 lower limbs) had hypoplastic anterior tibial veins, 6% (27 out of 432 lower limbs) posterior tibial veins and 0.7% (3 out of 432 lower limbs) peroneal veins. The incidence of hypoplastic veins did not differ between right and left limbs, between gender and age of the patients (all p>0.05). In neither of the limbs we have visualised venous agenesis. Most frequently (49 out of 79 hypoplastic veins) anterior tibial vein hypoplasticity was diagnosed. However hypoplastic peroneal veins were visualised only in three patients (Table 1 and 2). Data on popliteal vein are presented in Table 3. In total there have been 51% (220 out of 432 limbs) popliteal vein true and false duplications visualised. Out of these 176 were duplications, whereas five triple or complex. Jointly 181 (42%) popliteal vein duplications were diagnosed, out of which true duplications recorded in 39 (9%) out of 432 lower limbs. The length of duplicated popliteal vein in both limbs was ranging from 6.0 up to almost more than 8.9 cm with average length being 7.5±6.9 cm. Length of duplications in the right and left limb as well as intra-gender differences have been significantly different (p<0.05). The origin of popliteal vein at popliteal fossa level was found in only six (1%) of patients' limbs, proximally from fossa in 269 (62%) of cases and distally from the knee joint in 157 (36%) out of 432 lower limbs. Within a popliteal fossa a single vessel was identified in 47 (11%) of phlebograms, two vessels in 307 (71%) phlebograms, three or more vessels in 78 (18%) out of 432 lower limbs. The incidence of popliteal veins did not differ between patients' age and gender (p>0.05). However there was a statistically significant incidence of true popliteal vein duplication found between patients' age and gender (p<0.05). Full details provided in Table 4. FV duplications were found in 188 (43%) out of 432 limbs, out of which the majority 38% (166 out of 188) were double (Figure 1b). The remaining 5% (22 out of 432) had more complex venous system. Complex femoral veins provided in Figure 1a. Medial duplications (Figure 2a) found in 120 (63%) of 188 duplicated vessels, out of which 74 (39%) originated in the middle of the thigh (above adductor channel) and 68 (36%) originated in the adductor channel area. The length of duplicated femoral veins in both limbs differed from 1 up to more than 30 cm, with average length 14.9 ± 6.1 cm (standard deviation): 13.5 ± 6.0 cm duplicated and 16.5 ± 7.4 cm complex duplicated veins. More details can be found in Tables 4 and 5. In cases of complex venous segment (triple/complex) these were longer than double veins (p < 0.05 in both limbs). In comparison to duplications, complex veins were located in adductor channel projection (p < 0.05 for both limbs). Out of 188 femoral veins duplications 122 (65%) femoral vein diameters were smaller than one third of the main femoral vein, but 53 (28%) were half the diameter. In only small number of cases, that is 13 out of 188 (7%) was the duplicated FV the same size. Most frequently in 32% of cases (130 out of 432 limbs) there was FV seen without duplication with popliteal vein originating from the knee joint level (Figure 3a). Out of FV duplication types 19% (83 out of 432 limbs) FV duplications were found with popliteal veins originating proximally from the knee joint. Most frequently found popliteal vein variations were true duplications (5%) originating and ending in popliteal fossa region (Figure 3.O). Axial transformation of FV (Figure 2b) was found in 22% (95 out of 432 limbs) cases. No duplications were found in common iliac veins and deep femoral veins. However in three (0.7%) patient limbs external iliac vein duplications were found. All three external iliac vein duplications were located in the right limb. Common femoral vein duplications were found in 11 (3.5%) cases in both limbs. Seven duplications were located in the right limb and four in the left limb (Tables 6 and 7). On comparison of common femoral vein duplications between right and left patient limbs it was found that the incidence of common femoral vein duplications is significantly different between two limbs (p=0.008). Upon assessment of phlebograms DVT was found in 6% (24 out of 432) cases. Right limbs of the patients had DVT in 11 (5%) of phlebograms analysed and left limbs had DVT in 13 phlebograms (6%). No significant difference found between in gender prevalence (p=0.266) (Table 6). DISCUSSION There was a significant range in the length of duplicated veins. The lengths of duplications did not differ on average in terms of the size, both on comparison of patients' limbs and gender differences. Only popliteal vein short duplications lengths have shown significant differences on comparison between genders and right and left limbs. In our study the dominant limb of the patient was the left limb, which was found to have significant differences in longer duplications. Similar findings were published in the study of Park et al. Hypoplastic calf veins were found comparatively more often (18%). We compared the studies of Eifert and their findings have significantly differed from our results, where 392 patients were studied and 8% of calf veins were found to be hypoplastic. This study has included patients with already diagnosed congenital vascular malformations (1). Data provided by our study also differs from Quinlan et al results (5), where they report the majority (65%) of cases in popliteal vein duplications lengths to originate distally from the knee joint. In our study we found that in 62% of cases popliteal vein was originating proximally from the knee joint, which is similar to the findings of Park et al (5). Such differences could again be explained by different study methodology, where, for example, Quinlan et al study analysed only the phlebograms of the patients participating in enoxaparin study (MEDENOX) (5). All patients with a history of DVT were excluded from the study. In the study of Park et al the analysis of venous system was performed using computer tomography images and not phlebograms. This study included patients with varicose veins complications and the analysis was made based on perioperative imaging studies (4). An important hypothesis is whether duplication is a separate DVT risk factor. In our study in non-duplicated limbs there have been only 6% (24 out of 432) DVT cases recorded. This number is different from the previously published data of other authors. Liu et al study has recorded DVT in 19% of patients (3). In our study and also other published studies the hypothesis of increased DVT risk at auxiliary diagnosed duplications was not confirmed. Different methodology of our study could have influenced this result. In the study performed by Liu et al there were patients with high DVT risk analysed however symptomatic DVT patients were not excluded from the study (3). As a bias for the study authors should point out fact, that all patients included in this study had high DVT risk, much higher than in the average Latvian population due to orthopaedic surgery they underwent (7). CONCLUSIONS We conclude that there are frequent anatomic variations in FV and popliteal veins seen in Latvian population. In almost every sixth Latvian person there is some form of deep veins hypoplasia found. Conflict of interest: None REFERENCES 1. Eifert S, Villavicencio JL, Kao TC, Taute BM, Rich NM. Prevalence of deep venous anomalies in congenital vascular malformations of venous predominance // J Vasc Surg, 2000 Mar; 31(3):46271. 2. Evans CJ, Fowkes FG, Ruckley CV, Lee AJ. Prevalence of varicose veins and chronic venous insufficiency in men and women in the general population: Edinburgh Vein Study// J Epidemiol Community Health, 1999; 53:149­153. 3. Liu GC, Ferris EJ, Reifsteck JR, Baker ME. Effect of anatomic variations on deep venous thrombosis of the lower extremity // AJR Am J Roentgenol, 1986; 146:845­848. 4. Park EA, Chung JW, Lee W, Yin YH, Ha J, Kim SJ, Park SH. Three-Dimensional Evaluation of the Anatomic Variations of the Femoral Vein and Popliteal Vein in Relation to the Accompanying Artery by Using CT Venography // Korean J Radiol, 2011 May-Jun; 12(3): 327­340. 5. Quinlan DJ, Alikhan R, Gishen P, Sidhu PS. Variations in Lower Limb Venous Anatomy: Implications for US Diagnosis of Deep Vein Thrombosis // Radiology, 2003; 228:443­448 6. White RH. Epidemiology of Venous Thromboembolism // Circulation, 2003; 107 (23) I­3. 7. Paiement GD, Mendelsohn C. The risk of venous thrombembolism in the orthopedic patient: epidemiological and physiological data // Orthopedics, 1997; 20 Suppl:7-9. Table 1. Comparison of hypoplastic deep veins in the right and left calf of patients Hypoplastic Vein Right Limb 20 12 2 34 Left Limb 29 15 1 45 Both Limbs (n = 432) 49 (11%); p>0.05 27 (6%); p>0.05 3 (0,7%); p>0.05 79 (18%); p>0.05 Anterior tibial veins Posterior tibial veins Peroneal veins Total Table 2. Incidence of hypoplastic calf veins in different genders Hypoplastic vein Anterior tibial veins Posterior tibial veins Peroneal veins Total Females 21 13 1 35 Males 28 14 2 44 Total (n=432) 49 (11%); p > 0.05 27 (6%); p > 0.05 3 (0,7%); p > 0.05 79 (18%); p > 0.05 Table 3. Origin of popliteal vein and number of vessels in popliteal fossa Origin of popliteal vein At knee joint level Proximally from knee joint Distally from knee joint Number of vessels in popliteal fossa region Single Double Three or more 6 (1%) p>0.05 269 (62%) p>0.05 157 (36%) p>0.05 47 (11%); p>0.05 307 (71%); p>0.05 78 (18%); p>0.05 39 (9%); p<0.05 Address: Regina Zarina University of Latvia 13 Pilsonu Street, LV-1002, Riga, Latvia Email: regina_zarina@inbox.lv True popliteal vein duplication Table 4. Average length of FV and popliteal vein duplications in different limbs Length of duplications (cm) Popliteal vein duplication True popliteal vein duplication FV duplication True FV duplication Right Limb 7.4 ± 0.7 3.2 ± 0.5 14.3 ± 6.1 19.1 ± 6.4 Left Limb 7.6 ± 0.7 4.2 ± 0.8 13.6 ± 6.2 16.0 ± 6.5 Both Limbs (n = 432) 7.5 ± 0.7; p > 0.05 4.0 ± 0.6; p < 0.05 13.5 ± 6.0; p > 0.05 16.5 ± 7.4; p < 0.05 Table 6. Incidence of deep vein duplications in different limbs Duplication Common iliac vein External iliac vein Common femoral vein Femoral vein Deep femoral vein Popliteal vein True popliteal vein duplication Right Limb 0 3 7 94 0 88 17 Left Limb 0 0 4 94 0 93 22 0 3 (0.7%); p < 0.05 11 (2.5%); p < 0.05 188 (43.5%); p > 0.05 0 181 (42%); p > 0.05 39 (9%); p < 0.05 Both Limbs (n=432) Table 5. Position, length and lowest point of FV duplication FV Position Medial Lateral Both Length (cm) 1-5 6-10 11-20 21-30 >30 Lowest point Under patella Above patella In adductor channel Above adductor channel 2 26 25 40 1 17 43 34 3 (2%); p > 0.05 43 (23%); p > 0.05 68 (36%); p < 0.05 74 (39%); p < 0.05 4 22 52 15 1 6 31 44 12 1 10 (5%); p > 0.05 53 (28%); p > 0.05 96 (51%); p > 0.05 27 (14%); p > 0.05 2 (1%); p > 0.05 53 32 9 59 33 3 120 (63%); p > 0.05 56 (30%); p > 0.05 12 (6%); p > 0.05 Right Limb Left Limb Both Limbs Table 7. Duplications of deep veins in different genders Duplications Common iliac vein External iliac vein Common femoral vein Femoral vein Deep femoral vein Popliteal vein True popliteal vein duplication Females 0 2 7 Males 0 1 4 Total (n=432) 0 3 (0.7%); p > 0.05 11 (2.5%); p < 0.05 188 (43.5%); p > 0.05 0 181 (42%); p > 0.05 39 (9%); p < 0.05 Table 8. Isolated FV duplications and DVT a) b) Fig. 2. a) Medial duplication of FV; b) Axial transformation of deep femoral vein and duplication of FV a) b) Fig. 3: Variations in deep femoro-popliteal veins (adopted from Park et al, 2011) (4) Fig. 1. a) Complex femoral vein duplication; b) Simultaneous duplication of femoral and popliteal veins

Journal

Acta Chirurgica Latviensisde Gruyter

Published: Dec 1, 2013

There are no references for this article.