In vitro evaluation of radiopacity of contrast-loaded superabsorbent polymer microspheres (SAP-MS) with static imaging and flow model
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To evaluate the radiopacity of contrast-loaded superabsorbent polymer microspheres (SAP-MS) under X-ray imaging.
Materials and methods
SAP-MS were suspended in contrast material (iodixanol) and the diameter change was assessed. The diameter of contrast-loaded SAP-MS in saline was measured sequentially. Radiography of the contrast-loaded SAP-MS was evaluated as radiopacity by contrast-to-noise ratio and visibility by multiple reader scoring. Under digital subtraction angiography, contrast-loaded SAP-MS were injected into a flow model. The flow speed was 1–10 cm/s, and images were acquired at 1–7.5 frames per second using a pulse width of 10–85 ms. Images were assessed by multiple reader scoring.
The diameter of SAP-MS increased to 4.0–5.0 times its original size for approximately 15 min. The diameter of contrast-loaded SAP-MS in saline further increased by 10–30% within several minutes and returned to the previous size. Radiopacity and visibility of contrast-loaded SAP-MS decreased in 30 min after mixing with saline. Visibility was better with slow flow speed and narrow pulse width.
For effective observation, contrast-loaded SAP-MS should be kept in non-diluted contrast material until use. The conditions of slower flow and use of a narrow pulse width are recommended.
KeywordsEmbolization Microspheres Radiopacity Radiopaque beads
This study was not supported by any funding.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
- 2.Bonomo G, Pedicini V, Monfardini L, Della Vigna P, Poretti D, Orgera G, et al. Bland embolization in patients with unresectable hepatocellular carcinoma using precise, tightly size-calibrated, anti-inflammatory microparticles: first clinical experience and one-year follow-up. Cardiovasc Intervent Radiol. 2010;33:552–9.CrossRefGoogle Scholar
- 9.Hori S, Okada A, Sakamoto K, Jiaqi Y, Minamitani K, Inaba F, et al. A new embolic material: super absorbent polymer microsphere and its embolic effects. Jpn J Intervent Radiol. 1996;11:375–81 (in Japanese).Google Scholar
- 10.Jiaqi Y, Hori S, Minamitani K, Hashimoto T, Yoshimura H, Nomura N, et al. A new embolic material: super absorbent polymer (SAP) microsphere and its embolic effects. Nihon Igaku Hoshasen Gakkai Zasshi. 1996;56:19–24 (in Japanese).Google Scholar
- 13.Flory PJ. CHAPTER XIII. Phase equilibria in polymer systems. Principles of polymer chemistry. 1st ed. Ithaca: Cornell University Press; 1953. p. 584–9.Google Scholar