Effect of Lymphaticovenous Anastomosis on Muscle Edema, Limb, and Subfascial Volume in Lower Limb Lymphedema: MRI Studies

Abstract

Background: Although satisfactory volume reduction in secondary unilateral lower limb lymphedema after lymphaticovenous anastomosis (LVA) in the affected limb has been well reported, alleviation of muscle edema and the impact of LVA on the contralateral limb have not been investigated.

Study design: This retrospective cohort study enrolled patients who underwent supermicrosurgical LVA between November 2015 and January 2017. Pre- and post-LVA muscle edema were assessed using fractional anisotropy (FA) and apparent diffusion coefficient (ADC). The primary endpoint was changes in limb/subfascial volume assessed with magnetic resonance volumetry at least 6 months after LVA.

Results: Twenty-one patients were enrolled in this study. Significant percentage reductions in post-LVA muscle edema were found in the affected thigh (83.6% [interquartile range = range of Q1 to Q3; 29.8-137.1] [FA], 53.3% [27.0-78.4] [ADC]) as well as limb (21.7% [4.4-26.5]) and subfascial (18.7% [10.7-39.1]) volumes. Similar findings were noted in the affected lower leg: 71.8% [44.0-100.1] (FA), 59.1% [45.8-91.2] (ADC), 21.2% [6.8-38.2], and 28.2% [8.5-44.8], respectively (all p < 0.001). Significant alleviation of muscle edema was also evident in the contralateral limbs (thigh: 25.1% [20.4-57.5] [FA]; 10.7% [6.6-17.7] [ADC]; lower leg: 47.1% [35.0-62.8] [FA]; 14.6% [6.5-22.1] [ADC]; both p < 0.001), despite no statistically significant difference in limb and subfascial volumes.

Conclusions: Our study found significant reductions in muscle edema and limb/subfascial volumes in the affected limb after LVA. Our findings regarding edema in the contralateral limb were consistent with possible lymphedema-associated systemic influence on the unaffected limb, which could be surgically relieved.

Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American College of Surgeons.

Figures

Figure 1.

Inclusion and exclusion criteria for patient selection. DTI, diffusion tensor imaging; LLL, lower limb lymphedema; LVA, lymphaticovenous anastomosis; VLNT, vascularized lymph node transfer.

Figure 2.

A 65-year-old woman with BMI 22.8 kg/m2, who had received endometrial cancer ablation and lymph node dissection 5 years ago with postoperative radiotherapy, suffered from stage II to III left lower limb lymphedema for 4 years with 2 cellulitis episodes. A total of 8 lymphaticovenous anastomoses (LVA) were performed. (A) Lymphoscintigraphy showing marked radiocolloid stasis in her left lower (affected) limb without evidence of lymphedema in her right lower (contralateral) limb. (B) Pre-LVA appearance of lower limbs demonstrating prominent swelling in the affected limb. (C) Appearance of lower limbs at 2 years and 6 months post-LVA follow-up with notable improvements in both legs and contralateral ankle. (D) Pre-LVA magnetic resonance (MR) volumetry showing notably increased volume of the affected limb (affected limb 8,273.0 mL; contralateral limb 6,059.2 mL). (E) Post-LVA percentage volume reductions assessed with MR volumetry at 2 years and 6 months follow-up of her affected and contralateral lower limbs were 63.4% [(8,273.0 mL – 6,691.5 mL)/(8,273.0 mL – 5,779.0 mL) × 100%] and 4.6% [(5,779.0 mL – 6,059.2 mL)/6,059.2 mL × 100%], respectively.

Figure 3.

Preoperative magnetic resonance diffusion tensor imaging (DTI) and volumetry acquisition for a 52-year-old man with a BMI of 34.0 kg/m2 suffering from stage III right lower limb lymphedema. (A) Computation of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) through selecting 4 sets of regions of interest (ROI; small white rectangles) in the muscle compartment by a senior radiologist at 4 different levels (a: proximal thigh; b: distal thigh; c: proximal lower leg; d: distal lower leg) of the affected (lymphedematous) and contralateral limbs. Preoperative volumetric calculations of limb volume (B) and subfascial volume (C).

Figure 4.

Percentage reduction in muscle edema after lymphaticovenous anastomosis (LVA) assessed with fractional anisotropy (FA) and apparent diffusion coefficient (ADC). In the contralateral limbs, (A) and (B) both demonstrated significant post-LVA reductions at all 4 different levels (distal/proximal lower leg and distal/proximal thigh; both †‡p < 0.001). In the affected limbs, (D) and (E) followed the same trend (both †‡p < 0.001). (C) The average values of FA and ADC both demonstrated significant post-LVA reductions in the regions of lower leg and thigh of the contralateral, and (F) the affected limbs (both †‡p < 0.001). Statistical analyses were performed with Kruskal−Wallis rank sum test and Mann–Whitney Wilcoxon test which were represented by † and ‡, respectively.

Figure 5.

Percentage reductions in limb and subfascial volumes after lymphaticovenous anastomosis (LVA) quantified by magnetic resonance (MR) volumetry. Nonsignificant post-LVA reductions in (A) limb volume [lower leg and thigh (†p = 0.79 and 0.24, respectively] (‡p = 0.53), and (B) subfascial volume (†p = 0.79 and 0.40, respectively; ‡p = 0.82) of the contralateral limbs. Significant reductions in post-LVA (C) limb, and (D) subfascial volumes in lower leg and thigh of the affected limb (all †‡p < 0.001). Statistical analyses were performed with Kruskal−Wallis rank sum test and Mann–Whitney Wilcoxon test that were represented by † and ‡, respectively.