Table 1 Current clinical application of lymphatic resolution

X-ray

lymphography

Lipiodol

No limit

 ~ 1 mm

Deep tissue penetration

Invasiveness,

Time consuming

Radiation exposure

Central and collecting lymphatic imaging

[25, 30,31,32,33]

Lymphoscintigraphy/SPECT

^99mTc-coupled

radioactive probes

No limit

1–1.5 cm

Deep tissue penetration, high sensitively

Exposure to ionizing radiation Planar image

Poor spatiotemporal resolution

Visualization of collecting lymphatic vessels and dermal backflow, Quantitative assessment of lymphatic function, SLN mapping

[26, 34,35,36,37,38]

MR lymphography

Gd-based tracers or SPIO

No limit

0.5–2 mm

High imaging depth, 3D imaging can be realized without radiation

Low lymphatic specificity of clinically approved contrast,

Venous signal interference,

High cost

Collecting lymphangiography, Functional (dynamic contrast-enhanced MRL) and morphological evaluation of lymphatic vessels, SLN mapping

[27, 39,40,41,42,43]

Fluorescence imaging

Mainly ICG

1.5–2.0 cm

In the μm range (Depending on the instrument and depth)

Simple operation, no ionizing radiation, high temporal and spatial resolution, low costs

Limited depth of imaging, serious self-aggregation, lack of better clinically-approved tracers

Precise imaging of peripheral lymphatic vessels, Visualization of dermal backflow and quantitative assessment of lymphatic function, SLN mapping

[28, 29, 44,45,46,47]