Indocyanine green (ICG) lymphography is superior to lymphoscintigraphy for diagnostic imaging of early lymphedema of the upper limbs.
BACKGROUND
Secondary lymphedema causes swelling in limbs due to lymph retention following lymph node dissection in cancer therapy. Initiation of treatment soon after appearance of edema is very important, but there is no method for early diagnosis of lymphedema. In this study, we compared the utility of four diagnostic imaging methods: magnetic resonance imaging (MRI), computed tomography (CT), lymphoscintigraphy, and Indocyanine Green (ICG) lymphography.


METHODS
Between April 2010 and November 2011, we examined 21 female patients (42 arms) with unilateral mild upper limb lymphedema using the four methods. The mean age of the patients was 60.4 years old (35-81 years old). Biopsies of skin and collecting lymphatic vessels were performed in 7 patients who underwent lymphaticovenous anastomosis.


RESULTS
The specificity was 1 for all four methods. The sensitivity was 1 in ICG lymphography and MRI, 0.62 in lymphoscintigraphy, and 0.33 in CT. These results show that MRI and ICG lymphography are superior to lymphoscintigraphy or CT for diagnosis of lymphedema. In some cases, biopsy findings suggested abnormalities in skin and lymphatic vessels for which lymphoscintigraphy showed no abnormal findings. ICG lymphography showed a dermal backflow pattern in these cases.


CONCLUSIONS
Our findings suggest the importance of dual diagnosis by examination of the lymphatic system using ICG lymphography and evaluation of edema in subcutaneous fat tissue using MRI.
Department of Plastic Surgery and Reconstructive Surgery, The University of Tokyo, Tokyo, Japan. mihara@keiseigeka.name
Makoto
M
Mihara
Hisako
H
Hara
Jun
J
Araki
Kazuki
K
Kikuchi
Mitsunaga
M
Narushima
Takumi
T
Yamamoto
Takuya
T
Iida
Hidehiko
H
Yoshimatsu
Noriyuki
N
Murai
Kito
K
Mitsui
Taro
T
Okitsu
Isao
I
Koshima
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007208:Indocyanine Green; D008209:Lymphedema / Q000000981:diagnostic imaging*; D008220:Lymphography / Q000379:methods*; D061305:Lymphoscintigraphy / Q000379:methods*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D034941:Upper Extremity / Q000000981:diagnostic imaging* / Q000473:pathology
D007208:Indocyanine Green