The value of sonographic microvascular imaging in the diagnosis of lipedema

BACKGROUND

Lipedema is a chronic disease marked by symmetric enlargement of painful nodular and fibrotic adipose tissue, predominantly affecting the limbs. Since there is no specific test or biomarker for this condition, years often pass before the diagnosis of lipedema is established for the first time, thereby causing psychosocial distress, including depression, eating disorders, and social isolation. Over the last few years several advanced Doppler-based technologies have been developed to visualize slow flow blood vessels and superficial microvascular architecture undetectable by traditional color Doppler flow imaging (CDFI).

OBJECTIVE

The aim of this study was to evaluate the superficial microvascular anatomy in lipedema patients compared to healthy controls and investigate the clinical significance of the Ultra Micro Angiography (UMA) technology in the diagnosis of lipedema. This new technique may contribute to reduce the diagnostic delay and, eventually, establish and guide treatment strategies toward a better therapeutic outcome in lipedema patients.

METHODS

25 patients with lipedema and ten healthy controls with no history of lipedema were included in this study. All ultrasound examinations were performed on a novel high-performance ultrasound system (Resona R9/Mindray) using CDFI and the UMA technique.

RESULTS

In all of the patients, Ultra Micro Angiography achieved the excellent visualization of microvascular structures, revealing that most lipedema patients showed grade 3 (n = 13) or grade 2 (n = 8) flow. UMA was superior to CDFI for depicting the microvascular structures.

CONCLUSIONS

Here we show that UMA imaging characterizes the subcutaneous microvasculature with an unprecedented accuracy. The method has the advantage of being sensitive to small, slow-flowing vessels. This allows for the assessment of the course of vessels and vascular pathologies in great detail. Thus, UMA as a non-invasive diagnostic method can improve diagnostic accuracy in lipedema.

Diagnostic imaging in lipedema: A systematic review

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.

Lipedema: The Use of Cultured Adipocytes for Identification of Diagnostic Markers

BACKGROUND

Lipedema, diagnosed most often in women, is a progressive disease characterized by the disproportionate and symmetrical distribution of adipose tissue, primarily in the extremities. Although numerous results from in vitro and in vivo studies have been published, many questions regarding the pathology and genetic background of lipedema remain unanswered.

METHODS

In this study, adipose tissue-derived stromal/stem cells were isolated from lipoaspirates derived from nonobese and obese donors with or without lipedema. Growth and morphology, metabolic activity, differentiation potential, and gene expression were evaluated using quantification of lipid accumulation, metabolic activity assay, live-cell imaging, reverse transcription polymerase chain reaction, quantitative polymerase chain reaction, and immunocytochemical staining.

RESULTS

The adipogenic potential of lipedema and nonlipedema adipose tissue-derived stromal/stem cells did not rise in parallel with the donors' body mass index and did not differ significantly between groups. However, in vitro differentiated adipocytes from nonobese lipedema donors showed significant upregulation of adipogenic gene expression compared with nonobese controls. All other genes tested were expressed equally in lipedema and nonlipedema adipocytes. The adiponectin/leptin ratio was significantly reduced in adipocytes from obese lipedema donors compared with their nonobese lipedema counterparts. Increased stress fiber-integrated smooth muscle actin was visible in lipedema adipocytes compared with nonlipedema controls and appeared enhanced in adipocytes from obese lipedema donors.

CONCLUSIONS

Not only lipedema per se but also body mass index of donors affect adipogenic gene expression substantially in vitro. The significantly reduced adiponectin/leptin ratio and the increased occurrence of myofibroblast-like cells in obese lipedema adipocyte cultures underscores the importance of attention to the co-occurrence of lipedema and obesity. These are important findings toward accurate diagnosis of lipedema.

CLINICAL RELEVANCE STATEMENT

Our study highlights not only the difficulty in lipedema diagnostics but also the tremendous need for further studies on lipedema tissue. Although lipedema might seem to be an underestimated field in plastic and reconstructive surgery, the power it holds to provide better treatment to future patients can not be promoted enough.

Characterization of somatic mutations in the pathogenesis of lipedema

Background

Lipedema, a complex and enigmatic adipose tissue disorder, remains poorly understood despite its significant impact on the patients' quality of life. Genetic investigations have uncovered potential contributors to its pathogenesis, including somatic mutations, which are nonheritable genetic alterations that can play a pivotal role in the development of this disease.

Aim

This review aims to elucidate the role of somatic mutations in the etiology of lipedema by examining their implications in adipose tissue biology, inflammation, and metabolic dysfunction.

Results

Studies focusing on leukocyte clones, genetic alterations like TET2 and DNMT3A, and the intricate interplay between adipose tissue and other organs have shed light on the underlying mechanisms driving lipedema. From the study of the scientific literature, mutations to genes correlated to three main pathways could be involved in the somatic development of lipedema: genes related to mitochondrial activity, genes related to localized disorders of subcutaneous adipose tissue, and genes of leukocyte clones.

Conclusions

The insights gained from these diverse studies converge to highlight the complex genetic underpinnings of lipedema and offer potential avenues for therapeutic interventions targeting somatic mutations to alleviate the burden of this condition on affected individuals.

Targeting Mast Cells: Sodium Cromoglycate as a Possible Treatment of Lipedema

Background

Mast cells are immune cells that mediate hypersensi-tivity and allergic reactions in the body, secreting histamine and other inflammatory molecules. They have been associated with different inflammatory conditions such as obesity and other adipose tissue di-sorders. Lipedema is a chronic disease characterized by an abnormal accumulation of adipose tissue on the legs and arms, pain, and other symptoms. Mast cells may play a role in the pathology of lipedema.

Objective

Pilot study to determine levels of histamine and its metabolites in lipedema subcutaneous adipose tissue (SAT) biopsy samples, and to test sodium cromoglycate for the treatment of mast cells in women with lipedema.

Methods

Biopsies from lipedema and control SAT were collected and analyzed histologically for the presence of mast cells. Mass spec-trometry was used to measure the levels of histamine, a key marker of mast cells, and its metabolites in SAT in women with lipedema and controls, and after a group of women with lipedema were administered oral and topical doses of sodium cromoglycate for two weeks.

Results

Histological examination of biopsies from lipedema patients confirmed the presence of mast cells. Metabolomic analysis revealed high levels of histamine and its metabolites in samples from women with lipedema compared to controls. Following a two-week treatment period, lipedema tissue samples exhibited reduced levels of histamine, suggesting a reduction of mast cell activity.

Conclusion

Sodium cromoglycate has the ability to stabilize mast cells and reduce histamine levels in lipedema patients, which could be useful in lowering the symptoms of lipedema.

Lipedema stage affects adipocyte hypertrophy, subcutaneous adipose tissue inflammation and interstitial fibrosis

Introduction

Lipedema is a painful subcutaneous adipose tissue (SAT) disease characterized by adipocyte hypertrophy, immune cell recruitment, and fibrosis in the affected areas. These features are thought to contribute to the development and progression of the condition. However, the relationship between lipedema disease stage and the associated adipose tissue changes has not been determined so far.

Methods

SAT biopsies of 32 lipedema patients, ranging across the pathological stages I to III, and 14 BMI- and age-matched controls were harvested from lipedema-affected thighs and non-symptomatic lower abdominal regions. Histological and immunohistochemical (IHC) staining and expression analysis of markers for adipogenesis, immunomodulation, and fibrosis were performed on the tissue biopsies.

Results

Lipedema patients showed increased adipocyte areas and a stage-dependent shift towards larger cell sizes in the thighs. Lipedema SAT was linked with increased interstitial collagen accumulation in the thighs, but not the lower abdominal region when compared to controls. There was a trend toward progressive SAT fibrosis of the affected thighs with increasing lipedema stage. Elevated gene expression levels of macrophage markers were found for thigh SAT biopsies, but not in the abdominal region. IHC staining of lipedema thigh biopsies confirmed a transiently elevated macrophage polarization towards an M2-like (anti-inflammatory) phenotype.

Conclusions

In summary, lipedema SAT is associated with stage-dependent adipocyte hypertrophy, stage-progressive interstitial fibrosis and elevated proportion of M2-like macrophages. The character of the inflammatory response differs from primary obesity and may possess an essential role in the development of lipedema.

Lipedema and the Potential Role of Estrogen in Excessive Adipose Tissue Accumulation

Lipedema is a painful fat disorder that affects ~11% of the female population. It is characterized by bilateral, disproportionate accumulation of subcutaneous adipose tissue predominantly in the lower body. The onset of lipedema pathophysiology is thought to occur during periods of hormonal fluctuation, such as puberty, pregnancy, or menopause. Although the identification and characterization of lipedema have improved, the underlying disease etiology remains to be elucidated. Estrogen, a key regulator of adipocyte lipid and glucose metabolism, and female-associated body fat distribution are postulated to play a contributory role in the pathophysiology of lipedema. Dysregulation of adipose tissue accumulation via estrogen signaling likely occurs by two mechanisms: (1). altered adipocyte estrogen receptor distribution (ERα/ERß ratio) and subsequent metabolic signaling and/or (2). increased release of adipocyte-produced steroidogenic enzymes leading to increased paracrine estrogen release. These alterations could result in increased activation of peroxisome proliferator-activated receptor γ (PPARγ), free fatty acid entry into adipocytes, glucose uptake, and angiogenesis while decreasing lipolysis, mitochondriogenesis, and mitochondrial function. Together, these metabolic alterations would lead to increased adipogenesis and adipocyte lipid deposition, resulting in increased adipose depot mass. This review summarizes research characterizing estrogen-mediated adipose tissue metabolism and its possible relation to excessive adipose tissue accumulation associated with lipedema.

Lipedematous scalp. A rare entity in the pediatric ageLipedema de cuero cabelludo: una entidad infrecuente en pediatría

Lipedematous scalp is an uncommon entity of unknown etiology, rarely described in the pediatric age. It is characterized by boggy thickening of the scalp predominantly located at the vertex and occiput, which acquires a cotton-like consistency. This condition is palpable rather than visible. It is a casual finding because it is usually asymptomatic, although it may involve alopecia, pruritus, or dysesthesia. We report a 10-year-old girl with lipedematous scalp without alopecia. Sonographic and MRI findings confirmed the diagnosis of lipidematous scalp.  El lipedema de cuero cabelludo o cuero cabelludo lipedematoso es una entidad infrecuente y de etiología desconocida, rara vez descrita en la edad pediátrica. Se caracteriza por un engrosamiento difuso y de tacto esponjoso del tejido celular subcutáneo localizado principalmente en vértex y occipucio. Suele ser un hallazgo casual dado que habitualmente cursa de forma asintomática, aunque puede asociar alopecia, prurito o disestesias. Presentamos el caso de una niña de 10 años de edad con lipedema de cuero cabelludo sin alopecia asociada. Los hallazgos ecográficos y de resonancia magnética confirmaron el diagnóstico de lipedema de cuero cabelludo.

Left ventricular rotational mechanics differ between lipedema and lymphedema: Insights from the three-dimensional speckle tracking echocardiographic MAGYAR-path study

The present study aimed to assess LV rotational mechanics by three-dimensional speckle-tracking echocardiography (3DSTE) in lipedema (n=25), lymphedema (n=26) patient groups with age- and gender-matched healthy controls (n=54). 3 lipedema and 4 lymphedema patients were excluded due to insufficient image quality for 3DSTE analysis. LV apical rotation (9.61 ± 4.25 degree vs. 6.40 ± 2.63 degree, p <0.05) and LV twist (13.83 ± 4.89 degree vs. 10.04 ± 3.56 degree, p <0.05) are impaired in lipedema patients as compared to matched controls; similar alterations in lymphedema were not found. Moreover, in some lipedema and lymphedema patients severe LV rotational abnormalities could be detected. Our results suggest that lipedema-associated impaired LV apical rotation and twist assessed by 3DSTE could be a novel differential diagnostic point between lipedema and lymphedema.

[Lipedema an often overlooked but treatable disease]

Lipedema an often overlooked but treatable disease Lipedema is a painful disease that affects some women between puberty and menopause through a subcutaneous fat accumulation especially in the lower extremities. Patients suffer from pain and pressure tenderness. The larger fat accumulation, especially on the inside of the thighs and knees, causes walking difficulties. This can successfully be treated by liposuction with good long-term results in terms of pain reduction and prevention of osteoarthritis development in the knee and ankle joints.

Lipoedematous scalp: is there an association with fatty infiltration of the parotid?

Lipoedematous scalp (LS) is an extremely rare condition characterised by a soft and boggy consistency in the scalp due to an increased layer of subcutaneous tissue.In this report, we present a case of LS in a 64-year-old Indian woman. Clinical examination revealed only vague boggy lumpiness involving the whole of occipital scalp extending to parietal scalp. MRI scalp showed diffuse fatty infiltration of the scalp, particularly at the posterior parietal and occipital convexity extending to both lateral aspects of the cranium, with homogeneous signal in keeping with fat. Incidentally MRI also found diffuse fatty infiltration of the parotids.The aethiopathogenesis of LS is still unknown, however it is believed that the hormone leptin could be the key hormone in the dysregulation of fat deposition and distribution. This case report highlights the subtle features with which these cases can present and explores the literature on reported cases of LS.