Compilation of recent publications on Lipoedema

Key Findings

• Study Group and Response Rate: The study involved 30 patients, a larger sample size compared to other prospective lipedema studies. The response rate was high at 86%, which is significantly better than other studies with lower response rates (e.g., 57%)​​.
• Use of Validated Test Instruments: Unlike previous research, this study employed four comprehensive validated questionnaires to assess the quality of life in its multidimensionality, allowing for better comparison with the norm population​​.
• Uniformity in Surgical Procedure: Liposuction was consistently performed by the same surgical team, enhancing the comparability of the results​​.
• Prospective Study Design: The study was designed as a prospective study with a uniform observation period of six months, making the results more objective and comparable across participants​​.
• Quality of Life Improvement: The hypothesis that liposuction in lipedema improves the quality of life as a multidimensional construct was confirmed. Significant improvements were observed in several quality of life dimensions, including friends, hobbies, health, living conditions, family life, and partner relationships​​.
• Emotional Stability: The Freiburg Personality Inventory (FPI-R) results indicated significant improvements in emotional stability post-operatively, with fewer patients classified as emotionally unstable six months after the surgery​​.
• Recommendations for Further Research: The study suggests that further research is needed to fully understand the long-term impact of liposuction in lipedema patients. It recommends follow-up surveys one and two years post-operatively and consideration of other conservative therapies like manual lymphatic drainage and compression​​.
• Encouragement for Health Insurance Support: The study encourages health insurance companies to support liposuctions for lipedema patients to improve their long-term well-being and to foster further research in this area​​.

Background: Diagnosing lipedema remains a challenge due to its heterogeneous presentation, co-existing diseases, and the lack of objective diagnostic imaging.

Objective: This systematic review aims to outline the currently available diagnostic imaging methods to characterize lipedema in the legs along with their diagnostic performance.

Methods: PubMed, Embase, Google Scholar, Scopus, and Web of Science were searched. The quality assessment of diagnostic accuracy studies (QUADAS) tool was used for quality assessment.

Results: Thirty-two studies describing a total of 1154 patients with lipedema were included for final analysis. Features for lipedema have been defined using ultrasound (increased subcutaneous adipose tissue), lymphoscintigraphy (slowing of the lymphatic flow and a frequent asymmetry between the lower extremities), computed tomography (symmetrical bilateral soft tissue enlargement without either skin thickening or subcutaneous edema), magnetic resonance imaging (increased subcutaneous
adipose tissue), MR lymphangiography (enlarged lymphatic vessels up to a diameter of 2 mm), and dual-energy X-ray absorptiometry (fat mass in the legs adjusted for body mass index (BMI) ≥ 0.46 or fat mass in the legs adjusted for total fat mass
≥ 0.384).

Conclusion: The diagnostic performance of currently available imaging modalities for assessing lipedema is limited. Prospective studies are needed to evaluate and compare the diagnostic performance of each imaging modality. Imaging techniques
focusing on the pathogenesis of the disease are needed.

Key Findings

1. Study Selection and Characteristics:
   • A total of 32 studies involving 1154 patients with lipedema were included.
   • The imaging techniques evaluated were ultrasound, lymphoscintigraphy, CT scan, MRI/MR lymphangiography, dual-energy X-ray absorptiometry (DXA), and indocyanine green lymphography.
2. Ultrasound:
   • Seven studies prospectively evaluated ultrasound findings, comparing lipedema patients with control populations (e.g., lymphedema and obesity patients, healthy controls).
   • Significant increases in cutis and subcutis thickness were observed in lipedema compared to healthy controls.
   • One study showed excellent performance of ultrasound in measuring pretibial subcutaneous fat thickness with high sensitivity and specificity.
3. Lymphoscintigraphy:
   • Eleven studies evaluated lymphoscintigraphy, often including control populations like lymphedema patients or healthy controls.
   • Delayed lymphatic transport and asymmetry in lymph transport were commonly observed in lipedema patients.
4. CT Scan:
   • Two studies reported increased subcutaneous fat characteristic of lipedema.
5. MRI/MR Lymphangiography:
   • Eight studies reported on MRI findings, with MRI and MR lymphangiography showing dilated distal lymphatic vessels in about 40% of cases.
6. DXA:
   • Two studies used DXA, presenting cutoff values for identifying lipedema based on leg fat mass ratios.
7. Indocyanine Green Lymphography:
   • Four studies revealed significant changes in superficial lymph flow in lipedema, including slower lymph flow and higher fluorescent intensity in the skin.
8. Diagnostic Accuracy:
   • Only three studies reported cutoff values for diagnosing lipedema, and five studies reported the diagnostic accuracy of imaging studies.
9. Limitations and Challenges:
   • The review highlighted variability in clinical diagnosis criteria and biases in patient selection and reference standards.
   • The diagnostic value of imaging techniques in lipedema is not thoroughly evaluated, and none of the imaging patterns found are pathognomonic for lipedema.
10. Conclusion:
    • Despite the availability of various imaging methods, no consensus exists on the best imaging technique to assess lipedema.
    • The study emphasizes the need for standardized diagnostic criteria and further research to validate imaging techniques for lipedema diagnosis.

These findings underscore the complexity and variability in diagnosing lipedema and the need for standardized approaches in clinical practice​​.

Background: Our aim is to propose a framework for the development of a research case definition of lipedema, based on current available literature and those observations that can be applied to future lipedema research with the intent to standardize and strengthen the scientific evidence base.

Methods and Results: We conducted a narrative review of the literature, and identified consensus characteristics and disputed characteristics that could be included in a research case definition of lipedema. After considering the strength of the evidence and how each characteristic might be measured in a research study, we recommended an approach for the development of a research case definition of lipedema that would be based on consideration of five agreed-upon characteristics, and five disputed, or less substantiated, characteristics as additional evidence to enhance specificity.

Conclusions: We present a case definition framework for lipedema drawn from the scientific literature that can be applied to future studies on lipedema. Utilizing this framework should help to increase the sensitivity and specificity of case definition and provide an opportunity for meta-analysis of clinical studies and facilitate future research intercomparisons.