Fig. 4: In vivo dual PA/SC-ULM image of a mouse popliteal lymph node.
From: Hybrid photoacoustic and fast super-resolution ultrasound imaging
a Near-infrared fluorescence lymphatic imaging (IVIS) of indocyanine green (ICG) shows the locations of mouse popliteal lymph nodes (PLNs) where ICG accumulates. The ICG solution (20 µL, 0.2 mg ml−1) was administered to both hind footpads and drained to PLNs within 15 min. The imaging area is 48 × 87 mm. b 3D ultrasound image of a mouse hind limp close to the popliteal fossa area. c 3D SC-ULM image shows the blood vessels within the hindlimb tissue near the PLN. d 3D PA imaging of ICG confirms the ICG accumulation in the PLN. Three laser wavelengths (750, 790, and 850 nm) are used for multi-wavelength PA imaging, and linear spectral unmixing is used for identifying ICG signal spectroscopically. e 3D dual PA/SC-ULM image. The PLN is labeled with ICG; the SC-ULM shows blood vessels surrounding/within the PLN. The 3D imaging volume in (b–e) is 22.9 mm (x) × 8.0 mm (y) × 1.6 mm (z).
