Anatomical variation at the sapheno-femoral junction

Termination of the great saphenous vein at variable levels

The assessment of the saphenofemoral junction (SFJ) is important in the diagnosis and treatment of venous reflux of the great saphenous vein (GSV). In the clinical practice of venous medicine, the SFJ is used to represent the region at which the saphenous arch connects with the common femoral vein (CFV). A number of notable variations of the SFJ have been documented, and rare variable courses of the GSV have been described recently. Our case study reports two unusual GSV terminations. In both cases, the SFJ was located below the confluence of the profunda femoris vein (PFV) with the femoral vein (FV). Case 1 showed the SFJ was formed by the GSV and FV; whereas case 2 showed the PFV was joined by the GSV after a transposition with the FV. Anatomical variations of the SFJ are rare; however, they are increasingly diagnosed with the use of duplex ultrasound. The identification of SFJ variants warrants a safe endovenous procedure and prevents surgical complications.

Lymphatic refill in ultrasound and lymphatic washout after lymphaticovenous anastomosis

BACKGROUND

Lymphaticovenous anastomosis (LVA) drains lymph accumulated in the lymphatic vessels into the veins (lymphatic washout). A method to identify the ideal lymphatic vessels to achieve washout has not been established. This study examined the relationship between lymphatic washout, lymphatic ultrasonographic findings, and surgical outcomes.

METHODS

We reviewed consecutive patients who underwent LVA for lower limb lymphedema between September 2020 and March 2021. Patients who lacked data were excluded. Preoperative ultrasonography was performed to measure the lymphatic diameter. After the probe was pressed against the skin and released, the reaction of the lymphatic vessels was classified as either refilled, crushed, undecidable, or solid. Intraoperatively, whether lymphatic washout was observed or not, was recorded and compared to preoperative findings using the chi-square test. In 54 limbs from 32 patients, the total number of LVA, number of anastomoses with washout, number of refills detected by ultrasound, and severity of lymphedema were compared with the surgical result (postoperative limb volume change) by multiple regression analysis (49 limbs whose pre-or postoperative circumference data were lacking or who underwent intensive compression therapy postoperatively were excluded).

RESULTS

Sixty-five patients were reviewed. After excluding six patients with missing data, 59 patients (103 limbs) were included. The median patient age was 63 years (interquartile range, 51-76 years). We performed LVA at 217 sites (mean, 2.1 anastomoses per limb). "Refilled" lymphatics were observed at 156 sites (71.6%) and significantly thicker than those classified as "undecidable" (p = .020 in the lower leg and p < .001 in the thigh). In the thigh, "refilled" lymphatics had a higher rate of a washout than those classified as "undecidable." In Pearson's correlation coefficient for the surgical result, as the number of washout positive LVA increased, the limb volume tended to decrease postoperatively (correlation coefficient: -0.25). However, multiple regression analysis did not identify any factors that significantly affected the surgical outcomes.

CONCLUSION

"Refilled" lymphatic vessels had a higher rate of intraoperative lymphatic washout after anastomosis.

Evaluation of lymphatic vessel diameters in healthy people using lymphatic ultrasound examination

OBJECTIVE

The aim of this study was to examine lymphatic diameters in lower limbs of healthy volunteers in different body positions using lymphatic ultrasound examinations.

METHODS

Thirty-five healthy volunteers participated in this study. Those who had a history of varicose veins in the leg, deep venous thrombosis, or surgery on their legs or abdomen were excluded. We measured the vertical width of the lymphatics with a 33 MHz linear ultrasound probe, at 20 cm above the knee (thigh) and 10 cm below the knee (lower leg). First, the participants were placed supine, then sitting, and then standing. We performed lymphatic ultrasound examinations in each body position. The Student t test was used to compare lymphatic vessel diameters in the supine, sitting, and standing positions. The significance level was set at .05.

RESULTS

Among 35 healthy volunteers, 17 were men and 18 were women. Mean age was 30.9 (range, 23-55) years. The mean body mass index was 21.3 kg/m² (range, 29.0-16.1 kg/m²). We could not detect lymphatic vessels in 1 thigh and 3 lower legs, leaving 69 thighs and 67 lower legs for evaluation. In the thigh, the mean lymphatic diameters in the supine and standing positions were 0.154 mm and 0.150 mm, respectively, which were not significantly different. In the lower leg, the mean lymphatic diameters in the supine, sitting, and standing positions were 0.160 mm, 0.163 mm, and 0.164 mm, respectively, which were not significantly different. In the thigh, the mean lymphatic diameter in the supine position was larger in the men (0.17 mm) than in the women (0.14 mm) (P = .022). Similarly, in the lower leg, the mean lymphatic diameter in the supine position was greater in the men (0.19 mm) than in the women (0.14 mm) (P = .0044). There was no correlation between the supine lymphatic diameters and the age or body mass index of the participants.

CONCLUSIONS

In healthy legs, lymphatic diameters do not change with body positioning. Supine lymphatic vessel diameters are greater in men than in women.

Diagnosis of Lymphatic Dysfunction by Evaluation of Lymphatic Degeneration with Lymphatic Ultrasound

Background: The standard examination for diagnosing lymphedema is lymphoscintigraphy, which has a disadvantage in versatility and radiation exposure. We have reported the usefulness of echography in observing the lymphatic degeneration. The purpose of this study was to investigate the usefulness of lymphatic ultrasound in diagnosing lymphedema. Methods and Results: The study included 14 patients (28 lower limbs) who underwent lymphaticovenous anastomosis for lower limb lymphedema. Preoperative echography with a common 18-MHz linear probe was used to detect lymphatic vessels. We evaluated abnormal expansion or sclerosis of lymphatic vessels in the medial legs, which indicated the presence of lymphedema. We proposed the method "D-CUPS" on how to detect and observe the lymphatic vessels. We then performed indocyanine green (ICG) lymphography to diagnose lymphedema. The results of examination were compared. Stage 1 lymphedema was diagnosed in 9 limbs, Stage 2a in 7, Stage 2b in 8, and Stage 3 in 4. Lymphatic vessel detection was possible in all 28 medial thighs and in 27 medial lower legs. The sensitivity and specificity for diagnosis of lymphedema based on echography of the medial leg were 95.0% and 100.0%, respectively. The accuracy rate was 94.6%. We could detect lymphatic vessels with echography in 39 of 54 areas that failed detection using lymphoscintigraphy or ICG lymphography (72.2%). Conclusion: The location and degeneration of lymphatic vessels in lymphedematous limbs can be evaluated with a commonly used ultrasound device. Although exclusion of comorbidities is still necessary, lymphatic ultrasound has potential for use in diagnosis of lymphedema or lymphatic dysfunction.

Change of the Lymphatic Diameter in Different Body Positions

Background: Until now, lymphatic ultrasound was performed with the patients in the prone position. The aim of this study was to evaluate the change in the lymphatic diameter in different body positions. Methods: We performed a retrospective study. We performed indocyanine green (ICG) lymphography and lymphatic ultrasound as a pre-operative examination for lymphaticovenous anastomosis (LVA). ICG was injected at three lymphosomes per limb (the saphenous lymphatics, lateral thigh lymphatics, and lateral calf lymphatics). For the lymphatic ultrasound, a commonly used ultrasound device with an 18 MHz linear probe was employed. We measured the lymphatic diameter in the designed LVA sites in prone, sitting, and upright position. Results: We investigated 61 limbs of 31 female patients with lower limb lymphedema. The mean age was 62.0 (range: 42-86) years. We measured the lymphatic diameter at 78 sites in the thigh and 76 sites in the lower leg. In the thigh, the mean lymphatic diameters in the supine and upright positions were 0.43 ± 0.02 mm and 0.40 ± 0.02 mm, respectively, with no significant difference (p = 0.10). In the lower leg, the mean lymphatic diameters in the supine, sitting, and upright positions were 0.68 ± 0.04 mm, 0.63 ± 0.04 mm, and 0.63 ± 0.04, respectively. A significant decrease was noted between the supine and sitting positions (p = 0.02). Conclusions: The lymphatic diameter in the lymphedematous lower limbs tended to decrease when the patients changed their body position from supine to the sitting or upright positions.

Safety steps for a non-fluoroscopic approach in right-sided electrophysiology procedures: A point of view

Background

Electro-anatomic 3D mapping systems enable the fluoroscopy (FL) exposure to be reduced. In right-heart supraventricular tachycardia (SVT) procedures, FL could potentially be avoided. Our aim was to discuss some steps focusing on safety.

Methods and results

The patient cohort comprised 70 consecutive SVT patients who underwent electrophysiologic (EP) catheterization. FL was routinely avoided in all cases (54.2% males, age 57.2 ± 13.3 years): 51 ablations and 19 EP study procedures. The Carto^®3 (Biosense Webster) mapping system was used in 17/70 cases (24.3%), and the EnSite Precision™ (Abbott) system in the remaining 53/70 (75.7%). The mean procedure time was 94.1 ± 33.2 min; no FL was used. No major complications occurred. Acute procedural success was achieved in all 51 patients who underwent ablation. Over 3-month follow-up, arrhythmia recurred in 1 patient. There were no significant differences in procedural times between the two mapping systems, except for the time dedicated to the full geometry creation, which was longer for the EnSite Precision™ system: 10 min (8.5–15 IQR) vs 8 min (5–10 IQR) for the Carto^® system (p < 0.001) mainly due to the sub-diaphragmatic navigation. The following procedural steps were considered critical in order to safely avoid FL use: “loop” advancing of catheters, the use of a fixed intracardiac reference, His signal landmark centered maps and the careful acquisition of sub-diaphragmatic extracardiac geometry.

Conclusions

A routine zero X-ray approach by means of electro-anatomic 3D mapping systems is safe and effective in right-atrium procedures. Some ad-hoc discussed procedural steps may enhance safety.

Systematic review and meta-analysis of the anatomic variants of the saphenofemoral junction

BACKGROUND

The aim of this systematic review was to provide comprehensive data on the prevalence of variations of the saphenofemoral junction (SFJ) to prevent misidentification of the SFJ or the incomplete ligation of the tributaries of the great saphenous vein.

METHODS

A systematic review was conducted using the PubMed, Embase, and Cochrane Library databases through September 14, 2017. To be included in the meta-analysis, a study had to report prevalence data on the morphology of the SFJ or the presence of venous tributaries.

RESULTS

A total of 16 studies (7433 legs) were included. The majority of studies were performed during varicose vein surgery (74.14%), with fewer studies by means of computed tomography venography and cadaveric dissection. The pooled prevalence estimate (PPE) for a duplication of the SFJ with a bifid junction was 9.6% (P = .001). The PPE for a duplication of the SFJ with two separate junctions was 1.7%. The PPE for ectasia of the SFJ was 2.3% in type 1, 1.2% in type 2, and 1.7% in type 3. The distribution of the PPE for the number of venous SFJ tributaries was approximately normal with a slight right skew; a higher rate was observed in the group with four venous tributaries to the SFJ.

CONCLUSIONS

This analysis found high heterogeneity in the prevalence of SFJ anatomic variants and the number of venous SFJ tributaries. For this reason, it is highly recommended that a preoperative Doppler ultrasound assessment of the SFJ and great saphenous vein be performed.

Anatomic variations of lower extremity venous system in varicose vein patients: demonstration by three-dimensional CT venography

Background Understanding the anatomy of the lower extremity veins is essential for successful varicose vein treatment. Computed tomography (CT) venography may be used to obtain a comprehensive overview and detailed information regarding this. Purpose To describe anatomic variations of the lower extremity venous system in patients with varicose veins, using three-dimensional (3D) CT venography. Material and Methods A total of 810 limbs in 405 patients with suspected varicose veins were prospectively referred to undertake CT venography and included in our study population retrospectively. The CT venography images were evaluated by consensus of two cardiovascular radiologists. Anatomical variations of the lower extremity venous system and their incidence were analyzed. Specifically, the number of tributaries at saphenofemoral junction, relative location of the great saphenous vein (GSV) with respect to the common femoral artery bifurcation, pattern of saphenopopliteal junction, and end of thigh extension from the small saphenous vein (SSV) were assessed. Results The most frequent number of tributaries joining the GSV was four (44.4%, 360/810). Only 0.7% (6/810) of the limbs demonstrated unusual location of the GSV between the bifurcated superficial and deep femoral arteries. The most common pattern of veins at the saphenopopliteal junction was a larger caliber of saphenopopliteal junction than thigh extension from SSV (43.8%, 355/810), end of which joining the femoral vein directly (41.0%, 288/703). Conclusion CT venography with 3D reconstruction can be used to understand the anatomy of lower extremity veins and how their variations contribute to varicose veins.