Volumetric Differences in the Suprafascial and Subfascial Compartments of Patients with Secondary Unilateral Lower Limb Lymphedema

The Clinical Usefulness of Ultrasonographic Measurement Technique in Patients with Lower Extremity Lymphedema

Background: A previous study reported a new ultrasonography (US) measurement technique to evaluate the cross-sectional area (ΔCSA) of lymphedema in the upper extremity. This ΔCSA correlated well with parameters, such as the circumference, volumetry, and bioimpedance analysis (BIA) in healthy people and upper extremity lymphedema patients. This study examined whether a US measurement technique is clinically useful in patients with lymphedema in the lower extremity. Methods and Results: Forty patients diagnosed with unilateral lower extremity lymphedema were enrolled in this study. The subjects' leg circumference, BIA, isokinetic strength, and ΔCSA were examined on the same day. The leg circumference was measured at 15 cm above the knee (AK) and below the knee (BK) crease using a tape measure. BIA was performed by a trained physical therapist, and the data of impedance (Z) at 1 and 5 kHz of each side of the lower limbs and extracellular water (ECW) were used. A fully experienced physician measured soft tissue thickness, the distance between the skin and the fascia of the muscle, three times each at the anterior, medial, posterior, and lateral aspects of the bilateral legs by US at 15 cm AK and BK. The amount of soft tissue in the ΔCSA was calculated using the designed formula from the mean values of the thicknesses. Each parameter was calculated as the ratio of the sound side to the lesion side. The Pearson and Spearman correlation coefficients were used to assess the significance of these parameters. The ratio of ΔCSA measured at 15 cm AK and BK showed strong positive correlations with the circumference difference at the same level (rho = 0.790, p = 0.000, and rho = 0.882, p = 0.000, respectively). In addition, it showed moderate or strong correlations with the ratio of Z at 5 and 1 kHz in the BIA of the lower limbs (AK15, r = -0.511, p = 0.001 and r = -0.497, p = 0.001; BK15, r = -0.780, p = 0.000 and r = -0.756, p = 0.000, respectively). Although ECW and body mass index showed weak positive correlations with the ratio of ΔCSA measured at 15 cm BK, there was no significant correlation between the ratio of ΔCSA and the isokinetic muscle strength. Conclusion: The ΔCSA results showed moderate-to-strong correlations with other conveniently used methods except for the isokinetic muscle strength. As the US ΔCSA technique could measure lymphedema status with a structural consideration, it could also be recommended as a conventional measurement method in patients with upper and lower extremity lymphedema.

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

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.

Imaging biomarkers for diagnosis and treatment response in patients with lymphedema

Lymphedema is defined as a dysfunction of the lymphatic system producing an accumulation of lymphatic fluid in the surrounding tissue, as well as edema and fibrosis. A total of 250 million people worldwide are affected by this condition. Greater than 99% of these cases are related to a secondary cause. As there is a lack of curative therapy, the goal involves early diagnosis, in order to prevent the progression of the disease. Additionally, early diagnosis can aid in decreasing the demand for more complex surgical procedures. Currently, there is an impressive breadth of diagnostic tests available for these patients. We aimed to review the available literature in relation to the utilization of imaging biomarkers for the early diagnosis and treatment response in lymphedema.

Computed Tomography-Based Quantitative Analysis of Fibrotic Changes in Skin and Subcutaneous Tissue in Lower Extremity Lymphedema Following Gynecologic Cancer Surgery

Background: Lymphedema produces protein-rich fluids that aggravate inflammation in the skin and subcutaneous tissue. Inflammation then induces fibroadipose tissue deposition and fibrosis. However, few methods have been developed to evaluate the severity of fibrosis. Therefore, we aimed to evaluate the subcutaneous fibrotic changes in lower extremity lymphedema following gynecologic cancer surgery using an image analysis tool, the FIJI software. Methods and Results: Seventy-four patients with lymphedema following gynecologic surgery were enrolled in this study. We quantitatively analyzed the cross-sectional area (CSA) of soft tissue compartments, including subcutaneous tissue with the skin, muscle volume, fibrotic changes in subcutaneous tissue, and the perimeter of skin boundaries. The limb circumference and the CSA of the subcutaneous tissue and skin on the affected side were significantly larger than those on the unaffected side. Fibrotic changes showed the same trend. However, muscle volume patterns were different from those of the other compartments. Some patients showed lower muscle volume on the unaffected side than on the affected side. Circumference and cellulitis significantly affected the extent of fibrotic changes in the skin and subcutaneous tissues. Age and duration of lymphedema did not affect fibrosis. Conclusion: Fibrosis of subcutaneous regions with the skin can be quantitatively calculated using an image analysis tool in lower extremity lymphedema following gynecologic cancer surgery. Edema and cellulitis increase fibrotic changes in the subcutaneous tissue with the skin.

Liposuction of Breast Cancer-Related Arm Lymphedema Reduces Fat and Muscle Hypertrophy

Background: Adipose tissue deposition is a known consequence of lymphedema. A previous study showed that the affected arm in patients with nonpitting breast cancer-related lymphedema (BCRL) had a mean excess volume of 73% fat and 47% muscle. This condition impairs combined physiotherapy as well as more advanced microsurgical methods. Liposuction is, therefore, a way of improving the effects of treatment. This study aims to evaluate the tissue changes in lymphedematous arms after liposuction and controlled compression therapy (CCT) in patients with nonpitting BCRL.

Methods and Results: Eighteen women with an age of 61 years and a duration of arm lymphedema (BCRL) of 9 years were treated with liposuction and CCT. Tissue composition of fat, lean (muscle), and bone mineral was analyzed through dual energy X-ray absorptiometry (DXA) before, and at 3 and 12 months after surgery. Excess volumes were also measured with plethysmography. The median DXA preoperative excess volume was 1425 mL (704 mL fat volume, 651 mL lean volume). The DXA excess volume at 3 months after surgery was 193 mL (−196 mL fat volume, 362 mL lean volume). At 12 months after surgery, the median excess DXA volume was 2 mL (−269 mL fat volume, 338 mL lean volume). From before surgery to 3 months after surgery, the median DXA excess volume reduced by 85% (p < 0.001) (fat volume reduction 128% (p < 0.001), lean volume reduction 37% (p = 0.016)). From before surgery to 12 months after surgery, it reduced by 100% (p < 0.001) (fat volume reduction 139% [p < 0.001], lean volume reduction 54% [p = 0.0013]).

Conclusions: Liposuction and CCT effectively remove the excess fat in patients with nonpitting BCRL, and a total reduction of excess arm volume is achievable. A postoperative decrease in excess muscle volume is also seen, probably due to the reduced weight of the arm postoperatively.