Palpation of Increased Skin and Subcutaneous Thickness, Tissue Dielectric Constant, and Water Displacement Method for Diagnosis of Early Mild Arm Lymphedema

Breast Cancer-Related Lymphedema Assessed via Tissue Dielectric Constant Measurements

This review describes the use of tissue dielectric constant (TDC) measurements mainly in the assessment of breast cancer-related lymphedema (BCRL). PubMed, Web of Science, and EMBASE databases were initially searched using criteria that included the terms "dielectric" and "lymphedema." The initial search yielded a total of 131 titles. After removing studies not focused on upper extremity lymphedema, 56 articles remained. These articles, together with relevant articles from their bibliographies, formed the basis of the review. The findings show the potential utility and applications of TDC measurements to help detect and track BCRL, whether present in limbs, breasts, or trunks. It is reported as a non-invasive, simple-to-use method, with each measurement requiring less than 10 seconds, suggesting its practicality and useability as an in-office or in-clinic screening and tracking method. Although there are various ways to quantitatively evaluate lymphedema, most, if not all, are restricted to measurements on limbs. Thus, one significant advantage of the TDC approach is that almost any local region of interest can be effectively measured and tracked, which, for BCRL, could include specific regions of arms or hands, breasts, and truncal areas.

Assessment Modalities for Lower Extremity Edema, Lymphedema, and Lipedema: A Scoping Review

Lower extremity swelling may be broadly characterized as due to edema, lymphedema, or lipedema. Differentiation between these three conditions is important for providing appropriate treatment. This review analyzes and compares different clinical diagnostic modalities for these conditions, with the aim of assisting in the process of choosing the most appropriate diagnostic modality by highlighting the advantages and limitations of each. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for a systematic search of peer-reviewed literature, the following diagnostic methods for lower extremity swelling were investigated: (1) ultrasound (US), (2) lymphoscintigraphy (LSG), (3) computed tomography (CT), (4) bioimpedance spectroscopy (BIS), (5) tissue dielectric constant (TDC), and (6) magnetic resonance imaging (MRI), including magnetic resonance lymphangiography (MRL). The databases used in the search were PubMed, ProQuest, CINAHL Complete, Web of Science, Embase, and Biomedical Reference Collection. After retrieving 115 studies based on predetermined inclusion criteria, a total of 31 studies were critically evaluated. The main results indicate the following: duplex US is the modality of choice to initially identify lower extremity edema such as deep venous thrombosis (DVT) and venous reflux due to its high sensitivity and specificity. CT venography of the lower extremity appears to bethe preferred option for gynecologic cancer patients with lower extremity swelling post-treatment, as it measures subcutaneous tissue volumes to look for DVTs, lymphoceles, and cancer recurrence. TDC is a recommended modality for a variety of conditions, including edema and lymphedema, in part, due to its noninvasive localized assessment capabilities and ease of use. LSG emerges as an effective imaging modality for lymphedema characterization with minimal invasiveness and high sensitivity and specificity. BIS is widely used to identify and monitor lower extremity lymphedema but has been reported to have low sensitivity and lacks the ability to account for changes in tissue composition such as fibrosis. US and MRL are favored for lipedema diagnosis, with MRL providing comprehensive anatomical and functional insights, albeit with cost and accessibility limitations compared to US. While CT, MRI, US, and TDC are all useful for differentiating lymphedema from lipedema, MRI is the preferred modality due to its anatomical and functional diagnostic capabilities. However, US is a pragmatic alternative for use with obese patients or when MRI is not an option.

Medical Applications of Skin Tissue Dielectric Constant Measurements

Tissue dielectric constant (TDC) values assess certain skin properties that are dependent on multiple factors but mainly on the relative amount of water content within a locally measured tissue volume. Because of the non-invasive nature of these measurements and their ease of use, the method has been widely used in various medically related applications. The goal of this paper was to review and describe the uses and findings of such TDC measurements, considering and including the wide array of medical applications. The review is in part based on information derived from an analysis of published material obtained via literature searches of four major electronic databases and, in part, based on the author's experience with the TDC measurement methods and their various applications and his professional experiences. The databases searched were PubMed, Web of Science, EMBASE, and CINAHL Complete. Based on the initial search criteria, a total of 1257 titles were identified. After removing duplicates and filtering according to relevancy, 160 remained for detailed further review. In some cases, the bibliography of these retrieved articles provided additional sources. The findings demonstrate multiple research and medical uses and applications of TDC measurements, focusing on detecting and quantifying localized edema and lymphedema in multiple target sites. These include the upper and lower extremities, breasts, and trunk as regions involved in medical conditions causing lymphedema. In addition, the findings suggest that TDC evaluations are a convenient, non-invasive method to study and evaluate other conditions impacting skin, including diabetes mellitus and skin wounds or ulcers. Its ability to detect aspects of tissue changes simply and rapidly at almost any anatomical location makes it a useful tool for investigating multiple dermatological conditions and their treatment as future applications of this method.

Early Intervention with a Compression Sleeve in Mild Breast Cancer-Related Arm Lymphedema: A 12-Month Prospective Observational Study

BACKGROUND

In our previous randomized controlled trial (RCT), the progression/no progression of mild breast cancer-related arm lymphedema (BCRL) was examined among women randomized to a compression group (CG) with a compression sleeve (compression class (ccl) 1) or not (NCG) for 6 months. In the present prospective study, BCRL in the CG and NCG was followed for 12 months.

METHODS

At the end of the RCT, 33 women with mild BCRL were eligible in the CG and 37 in the NCG. The proportional differences in no progression/progression of BCRL were defined as a >2% increase from start of RCT or exceeding 10% in the lymphedema relative volume as measured by the water displacement method. In addition, changes in the lymphedema relative volume and tissue dielectric constant ratio, which measures local tissue water, were examined. At the end of the RCT (i.e., after 6 months), a one-month break of the compression treatment was made in the CG. If the lymphedema relative volume progressed by definition, the compression treatment was resumed and continued, with follow-up of all women at 9 and 12 months.

RESULTS

A larger proportion of women in the NCG showed progression (57%, 61%, 67%) compared to the CG (16%, 22%, 31%) at 6, 9, and 12 months (p < 0.001, 0.005, 0.012), respectively. Twelve (33%) women in the NCG did not progress at all. No changes of the lymphedema relative volume and local tissue water were found over time at any follow-ups, but were stable on a low level.

CONCLUSIONS

To avoid the progression of mild BCRL into a chronic issue in the long-term, compression sleeve ccl 1 may be applied immediately after early diagnosis of mild BCRL.

Variation in Leg Tissue Dielectric Constant Values of Healthy Young Adult Females With and Without Compression Bandaging

Background The clinical efficacy of a compression application has been often limited to the assessment of the change in limb volume, change in clinical symptoms (i.e., wound size, pain, range of motion, incidence of cellulitis), or vascular hemodynamics of the whole limb. Assessing compression-related biophysical changes of a localized area, such as around a wound, or in an area outside of an extremity cannot be objectively assessed by these measurements. Tissue dielectric constant (TDC) values, which provide a measure of the local tissue water (LTW) content, offer an alternative method to document variation in the LTW content of the skin in a specific location. The goals of the present research were (1) to characterize TDC values, expressed as percentage tissue water, from multiple areas along the medial aspect of the lower leg of healthy volunteers and (2) to explore the potential utilization of the TDC values to assess change in tissue water content in a localized area following compression applications. Methods TDC was measured at 10, 20, 30, and 40 cm proximal to the medial malleolus on the medial aspect of the right leg of 18 young adult healthy women with an age range of 18-23 years and a body mass index of 18.7 to 30.7kg/m^2.. TDC was measured at baseline and after 10 minutes of exercise with compression in place on three separate days during which three different compression applications were assessed: a longitudinal elastic stockinette, a two-layer cohesive compression kit, and a combination of the two. Leg circumferences and compression-related interface pressures were also measured. Results Test-Retest Reliability of circumferential measurements and TDC values evaluated using Intraclass correlation coefficient (ICC _3,1) revealed excellent and moderate-to-good reliability, respectively. Analysis of TDC values along the length of the limb using Friedman's test, revealed a small but statistically significant overall difference among baseline TDC values attributable to a smaller value at 40 cm. The largest difference in cumulative average was 7.7% which occurred between 20 and 40 cm, with all other differences between locations less than 1%. No significant differences between the compression applications were observed. Conclusion  The present findings demonstrate the utility of TDC measurements as a modality to assess compression-related changes in the legs of healthy women as a foundation for their potential use in assessing outcomes of compression treatments for persons with lower extremity edema or lymphedema. The absence of a significant change in TDC values in these healthy non-edematous conditions and the demonstrated reliability of the TDC measurements on three different days provides further support for the utility of such applications of TDC measurements. The extension to patients with lower extremity edema or lymphedema needs to be evaluated.

The Prevalence of Lower Limb and Genital Lymphedema after Prostate Cancer Treatment: A Systematic Review

(1) Background: Secondary lymphedema is a chronic, progressive, and debilitating condition with an important impact on quality of life. Lymphedema is a frequently reported complication in oncological surgery but has not been systematically studied in the setting of prostate cancer. (2) Methods: Pubmed/MEDLINE and Embase were systematically searched to identify articles reporting on lower limb or genital lymphedema after primary treatment (surgery of radiation therapy) of the prostate and the pelvic lymph nodes in men with prostate cancer. Primary outcome was the prevalence of lower limb and genital lymphedema. (3) Results: Eighteen articles were eligible for qualitative synthesis. Risk of bias was high in all included studies, with only one study providing a prespecified definition of secondary lymphedema. Eleven studies report the prevalence of lower limb (0-14%) and genital (0-1%) lymphedema after radical prostatectomy with pelvic lymph node dissection (PLND) Seven studies report a low prevalence of lower limb (0-9%) and genital (0-8%) lymphedema after irradiation of the pelvic lymph nodes. However, in the patient subgroups that underwent pelvic irradiation after staging pelvic lymph node dissections, the prevalence of lower limb (18-29%) and genital (2-22%) lymphedema is substantially elevated. (4) Conclusion: Prostate cancer patients undergoing surgery or irradiation of the pelvic lymph nodes are at risk of developing secondary lymphedema in the lower limbs and the genital region. Patients receiving pelvic radiation after pelvic lymph node dissection have the highest prevalence of lymphedema. The lack of a uniform definition and standardized diagnostic criteria for lower limb and genital lymphedema hampers the accurate estimation of their true prevalence. Future clinicals trials are needed to specifically evaluate secondary lymphedema in patients undergoing prostate cancer treatments, to identify potential risk factors and to determine the impact on quality of life.

Early intervention with compression garments prevents progression in mild breast cancer-related arm lymphedema: a randomized controlled trial

BACKGROUND

Early diagnosis and compression treatment are important to prevent progression in breast cancer-related arm lymphedema (BCRAL). However, some mild BCRAL can be reversible, and therefore, compression treatment may not be needed. The aim of this study was to investigate the proportion of women with mild BCRAL showing progression/no progression of lymphedema after treatment with or without compression garments, differences in changes of lymphedema relative volume (LRV), local tissue water and subjective symptoms during 6 months. Also, adherence to self-care was examined.

MATERIAL AND METHODS

Seventy-five women diagnosed with mild BCRAL were randomized to a compression group (CG) or noncompression group (NCG). Both groups received self-care instructions, and the CG were treated with a standard compression garment (ccl 1). Women in the NCG who progressed in LRV ≥2%, or exceeded 10% dropped out, and received appropriate treatment. The proportion showing progression/no progression of LRV, and changes in LRV was measured by Water Displacement Method. Changes in local tissue water were measured by Tissue Dielectric Constant (TDC), subjective symptoms by Visual Analogue Scale, and self-care by a questionnaire.

RESULTS

A smaller proportion of LRV progression was found in the CG compared to the NCG at 1, 2 and 6 months follow-up (p ≤ 0.013). At 6 months, 16% had progression of LRV in the CG, compared to 57% in the NCG, (p = 0.001). Thus, 43% in the NCG showed no progression and could manage without compression. Also, CG had a larger reduction in LRV, at all time-points (p ≤ 0.005), and in the highest TDC ratio, when same site followed, at 6 months (p = 0.025). Subjective symptoms did not differ between the groups, except at 1 month, where the CG experienced more reduced tension (p = 0.008). There were no differences in adherence to self-care.

CONCLUSION

Early treatment with compression garment can prevent progression in mild BCRAL. Trial registration: ISRCT nr ISRCTN51918431.

Impedance of Extracellular Fluid, Volume, and Local Tissue Water Can Be Reliably Measured in People With Lower Limb Lymphedema

OBJECTIVE

Lower limb lymphedema (LLL) is a chronic condition. To be able to evaluate changes of LLL over time and effects of interventions, reliable measurement methods are important. Currently, there is limited knowledge of the reliability of commonly used measurement methods in LLL. The study objective was to evaluate the test-retest (intrarater) reliability of impedance of extracellular fluid, volume, and local tissue water measurements in people with unilateral or bilateral LLL and measurement errors both for a group of people and for a single individual.

METHODS

Forty-two people with mild to moderate unilateral or bilateral, primary or secondary LLL were measured twice, 2 weeks apart. Impedance of extracellular fluid was measured by bioimpedance spectroscopy and calculated as arm-to-leg ratio, volume with circumference measurements every 4 cm, and local tissue water with tissue dielectric constant at 14 points. Test-retest reliability was evaluated using the intraclass correlation coefficient [ICC(2,1)], changes in the mean, SE of measurement in relative terms (SEM%), and the smallest real difference in relative terms (SRD%).

RESULTS

For the impedance ratio, the reliability was high [ICC(2,1) = 0.79-0.90] and the measurement errors were acceptable (SEM% = 5.0%-5.2%; SRD% = 14.0%-14.4%). For volume, the reliability was high (ICC = 0.99) and the measurement errors were low (SEM% = 1.1%-1.7%; SRD% = 3.1%-4.6%). For the tissue dielectric constant, the reliability was fair to excellent [ICC(2,1) = 0.68-0.96] and the measurement errors were acceptable (SEM% = 4.2%-9.7%; SRD% = 11.7%-26.8%).

CONCLUSIONS

Measurements of impedance of extracellular fluid, volume, and local tissue water are reliable in people with mild to moderate LLL. The measurement errors were acceptable in all 3 methods indicating that real, clinical changes in lymphedema can be measured both for a group of people and a single individual.

IMPACT

The results from this test-retest reliability study can help clinicians and researchers to interpret if real clinical changes in lymphedema occur over time or after an intervention in people with mild to moderate LLL.

Lymphedema Index Ratio As Predictive Factor of Treatment in Patients with Breast Cancer-Related Lymphedema

Background: This retrospective observational study aimed to evaluate the lymphedema index ratio to predict the effect of complex decongestive therapy (CDT) in patients with breast cancer-related lymphedema (BCRL) and to establish a lymphedema index ratio cutoff value for the extent of CDT effect. Materials and Methods: All 108 enrolled patients with BCRL underwent volume measurements and bioelectrical impedance analysis before and after CDT. The difference in percent excess volume (PEV) before and after CDT was defined as the therapeutic effect, and each patient was assigned to Groups A, B, or C based on therapeutic effects of 0%-5%, 5%-10%, and 10%-20%, respectively. Results: The mean lymphedema index ratios of Groups A, B, and C were 1.27, 1.38, and 1.46, respectively, with significant differences between the groups (p < 0.01). The cutoff lymphedema index ratio values for diagnosis between Groups A and B and between Groups B and C were 1.277 (sensitivity: 71.7%, specificity: 61.8%) and 1.357 (sensitivity: 76.9%, specificity: 62.1%), respectively. The Spearman coefficients for the linear relationship between lymphedema index ratio and initial PEV and between lymphedema index ratio and therapeutic effect were found to be significant at 0.615 and 0.360, respectively (p < 0.01). Conclusion: The results of this study found that the lymphedema index ratio may predict the volume reduction in patients with BCRL. A less reduction (therapeutic effect <5%) was predicted in patients with a lymphedema index ratio of <1.277, while a greater reduction (therapeutic effect >10%) was predicted in patients with a lymphedema index ratio of >1.357.

Tissue Dielectric Constant and Water Displacement Method Can Detect Changes of Mild Breast Cancer-Related Arm Lymphedema

Background: Most commonly, volume measurements are used to evaluate the effect of lymphedema treatment, but as the accumulation of lymph fluid can be local, this method may not always be the best. Tissue dielectric constant (TDC) can be applied to identify local lymphedema changes, but has not been used before when evaluating treatment in mild arm lymphedema. Thus, the overall aim of this study was to examine if TDC and water displacement method (WDM) can measure changes in mild breast cancer-related lymphedema during the 6-month standard treatment. More specifically, we examined changes within and between three defined groups based on lymphedema thresholds of TDC and WDM at start of treatment, as well as changes of the highest TDC ratio and site. Methods and Results: Forty-six women with mild arm lymphedema, received treatment with compression sleeves, mostly ccl 1, and instructions about self-care. Local tissue water was measured by TDC at six defined sites and lymphedema relative volume (LRV) by WDM before treatment and at first, second, third, and sixth month. There was a significant decrease in the site with the highest TDC ratio, as well as LRV at all follow-up visits. At 6 months, TDC ratio had decreased mean 0.26 (p < 0.001) and LRV mean - 3.3% (p < 0.001). There was a significant difference between the groups in change of TDC ratio, but not in LRV. Sixty percent changed the overall highest TDC ratio to another site during 6 months. Conclusion: Both TDC and WDM could detect changes in mild arm lymphedema but should be interpreted separately.