Cliotide T2

Objective: To assess for the first time the morphology of the lymphatic system in patients with lipedema and lipo-lymphedema of the lower extremities by MR lymphangiography. Materials and methods: 26 lower extremities in 13 consecutive patients (5 lipedema, 8 lipo-lymphedema) were examined by MR lymphangiography. 18 mL of gadoteridol and 1 mL of mepivacainhydrochloride 1% were subdivided into 10 portions and injected intracutaneously in the forefoot. MR imaging was performed with a 1.5-T system equipped with high-performance gradients. For MR lymphangiography, a 3D-spoiled gradient-echo sequence was used. For evaluation of the lymphedema a heavily T2-weighted 3D-TSE sequence was performed. Results: In all 16 lower extremities (100%) with lipo-lymphedema, high signal intensity areas in the epifascial region could be detected on the 3D-TSE sequence. In the 16 examined lower extremities with lipo-lymphedema, 8 lower legs and 3 upper legs demonstrated enlarged lymphatic vessels up to a diameter of 3 mm. In two lower legs with lipo-lymphedema, an area of dermal back-flow was seen, indicating lymphatic outflow obstruction. In the 10 examined lower extremities with clinically pure lipedema, 4 lower legs and 2 upper legs demonstrated enlarged lymphatic vessels up to a diameter of 2 mm, indicating a subclinical status of lymphedema. In all examined extremities, the inguinal lymph nodes demonstrated a contrast material enhancement in the first image acquisition 15 min after injection. Conclusion: MR lymphangiography is a safe and accurate minimal-invasive imaging modality for the evaluation of the lymphatic circulation in patients with lipedema and lipo-lymphedema of the lower extremities. If the extent of lymphatic involvement is unclear at the initial clinical examination or requires a better definition for optimal therapeutic planning, MR lymphangiography is able to identify the anatomic and physiological derangements and to establish an objective baseline.

Background: Invasive imaging techniques have been applied for lymphedema (LE) assessment; noncontrast MR lymphography (NCMLR) has potential as an alternative, but its performance is not known in secondary lower limb LE. Purpose: To assess the role of NCMRL for the classification and characterization of secondary lower limb LE. Study type: Retrospective. Population: Fifty adults with clinically diagnosed secondary LE. Field strength/sequence: 1.5T, 3D T2 -weighted turbo spin-echo, 3D T2 -weighted turbo spin-echo short tau inversion recovery. Assessment: Three radiologists assessed the following characteristics on NCMRL: honeycomb pattern, dermal thickening, muscular abnormalities, distal dilated lymphatics, inguinal lymph node number, appearance of iliac lymphatic trunks. An LE grading based on the MR images was assigned. The relationship between imaging findings and clinical staging was evaluated, as well as between dermal backflow at lymphoscintigraphy and MR staging, and between the limb swelling duration and peripheral lymphatics dilatation. Statistical tests: Pearson's correlation test and Cramer's V coefficient were computed to measure the strength of association. The Mann-Whitney test was used to compare the limb swelling duration between patients with and without dilated distal vessels. Agreement among raters was assessed through Kendall's W coefficient of correlation. Results: Clinical stage and the MR grading were correlated, with Cramer's V coefficient of 1 for reader 1 (P < 0.05), 0.846 for reader 2 (P < 0.05), and 0.912 (P < 0.05) for reader 3; agreement between interraters was very good (W = 0.0.75; P = 0.05). A honeycomb pattern (P < 0.05), dermal thickening (P < 0.001), muscular abnormalities (P < 0.05), iliac lymphatic trunks appearance (P < 0.05), distal dilated vessels (P < 0.05), and lymph nodes number (P < 0.05) were significantly correlated with LE clinical stage. Dermal backflow at lymphoscintigraphy was described in 10 (20%) patients and showed a significant correlation with the MR grading (P < 0.05). Data conclusion: These preliminary results suggest that NCMRL may provide information useful for the staging and management of patients affected by secondary lower limb LE. Level of Evidence 4 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2021;53:458-466.

Background: Lipedema exhibits excessive lower-extremity subcutaneous adipose tissue (SAT) deposition, which is frequently misidentified as obesity until lymphedema presents. MR lymphangiography may have relevance to distinguish lipedema from obesity or lymphedema. Hypothesis: Hyperintensity profiles on 3T MR lymphangiography can identify distinct features consistent with SAT edema in participants with lipedema. Study type: Prospective cross-sectional study. Subjects: Participants (48 females, matched for age [mean = 44.8 years]) with lipedema (n = 14), lipedema with lymphedema (LWL, n = 12), cancer treatment-related lymphedema (lymphedema, n = 8), and controls without these conditions (n = 14). Field strength/sequence: 3T MR lymphangiography (nontracer 3D turbo-spin-echo). Assessment: Review of lymphangiograms in lower extremities by three radiologists was performed independently. Spatial patterns of hyperintense signal within the SAT were scored for extravascular (focal, diffuse, or not apparent) and vascular (linear, dilated, or not apparent) image features. Statistical tests: Interreader reliability was computed using Fleiss Kappa. Fisher's exact test was used to evaluate the proportion of image features between study groups. Multinomial logistic regression was used to assess the relationship between image features and study groups. The odds ratio (OR) and 95% confidence interval (CI) of SAT extravascular and vascular features was reported in groups compared to lipedema. The threshold of statistical significance was P < 0.05. Results: Reliable agreement was demonstrated between three independent, blinded reviewers (P < 0.001). The frequency of SAT hyperintensities in participants with lipedema (36% focal, 36% diffuse), LWL (42% focal, 33% diffuse), lymphedema (62% focal, 38% diffuse), and controls (43% focal, 0% diffuse) was significantly distinct. Compared with lipedema, SAT hyperintensities were less frequent in controls (focal: OR = 0.63, CI = 0.11-3.41; diffuse: OR = 0.05, CI = 0.00-1.27), similar in LWL (focal: OR = 1.29, CI = 0.19-8.89; diffuse: OR = 1.05, CI = 0.15-7.61), and more frequent in lymphedema (focal: OR = 9.00, CI = 0.30-274.12; diffuse: OR = 5.73, CI = 0.18-186.84). Data conclusion: Noninvasive MR lymphangiography identifies distinct signal patterns indicating SAT edema and lymphatic load in participants with lipedema. Evidence level: 1 TECHNICAL EFFICACY: Stage 1.