A surface-modified chylomicron remnant-like emulsion for percutaneous computed tomography lymphography: synthesis and preliminary imaging findings.
OBJECTIVE
To assess a surface-modified emulsion as a percutaneous CT lymphographic agent in normal dogs.


METHODS
An iodinated chylomicron remnant-like microemulsion was formulated with a mean particle size of 91.3 nm and an iodine concentration of 91 mg I/mL. Contrast material (2 mL) was injected into the subcutaneous tissues of the metatarsus and metacarpus of six normal dogs to enhance popliteal and cervical lymph nodes, respectively. CT images were acquired at 0, 15, 30, 45, 60, 240, 480, and 1440 minutes.


RESULTS
Significant lymph node enhancement occurred in as little as 15 minutes after injection and persisted at least 8 hours. Node opacification was most pronounced at 1 to 4 hours postinjection and exceeded 200 HU in some nodes (precontrast attenuation = 45 HU). Marked enhancement of popliteal efferent lymphatics and of iliac and sacral node groups also occurred indicating distribution to second order nodes. Attenuation of enhanced nodes reverted to precontrast levels by 24 hours.


CONCLUSIONS
The new surface-modified, chylomicron remnant-like emulsion provided marked, selective enhancement of targeted lymph nodes after subcutaneous administration. Moreover, the formulation produced significant opacification of more distant node groups from a single injection.
Wisner
Erik R
ER
Department of Clinical Sciences, Ohio State University College of Veterinary Medicine, Columbus, Ohio, USA. erwisner@ucdavis.edu
Weichert
Jamey P
JP
Longino
Marc A
MA
Counsell
Raymond E
RE
Weisbrode
Stephen E
SE
D000818:Animals; D003287:Contrast Media / Q000737:chemistry* / Q000493:pharmacokinetics; D004285:Dogs; D004655:Emulsions; D007455:Iodine / Q000493:pharmacokinetics; D007480:Iopanoic Acid / Q000031:analogs & derivatives / Q000737:chemistry* / Q000493:pharmacokinetics; D008055:Lipids / Q000493:pharmacokinetics; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D008220:Lymphography / Q000295:instrumentation / Q000379:methods*; D008854:Microscopy, Electron; D010316:Particle Size; D051381:Rats; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*
D003287:Contrast Media; D004655:Emulsions; D008055:Lipids; C454326:n-butyliopanoate; D007455:Iodine; D007480:Iopanoic Acid