Evaluation of lymphedema in upper extremities by MR lymphangiography: Comparison with lymphoscintigraphy.

Abstract

Purpose: To validate usefulness of magnetic resonance (MR) lymphangiography for evaluation of peripheral lymphedema in upper extremities by comparison with lymphoscintigraphy.

Materials and methods: This prospective study had institutional review board approval and written informed consent was obtained from all patients. Initially, protocol of MR lymphangiography for upper extremity was established in seven healthy volunteers with 3.0T fat-saturated three-dimensional gradient-echo MR after gadobutrol injection. Then six patients with unilateral lymphedema of the upper extremities were examined with MR lymphangiography and lymphoscintigraphy, and the results were correlated with each other. Four categories were defined to scale the quality of drainage.Results of both techniques were separately evaluated by two radiologists and a nuclear physician. We evaluated sensitivity, specificity and correlation of both techniques.

Results: MR lymphangiography showed sensitivities of 100% for all four categories, while lymphoscintigraphy yielded a sensitivity of 83.3% for delineation of lymph vessels and 100% for the other three categories. Specificity of MR lymphangiography was 85.7% for delay of drainage and 100% for other three categories, while lymphoscintigraphy showed specificity of 66.7% for pattern of lymphatic drainage and 100% for other three categories. Delay and pattern of drainage was same in 83.3% and non-visualization of axillary LNs was indistinguishably noted in all patients on both techniques. Anatomic level of enhanced lymph vessel was identical in 66.7% of the patients.

Conclusion: MR lymphangiography showed better performance for depiction of lymph vessels. MR lymphangiography and lymphoscintigraphy yielded same results in all or most patients for evaluation of axillary lymph nodes enhancement and lymphatic drainage in upper extremity.