Quantitative Dual Contrast CT Technique for Evaluation of Articular Cartilage Properties. Academic Article uri icon

Overview

abstract

  • Impact injuries of cartilage may initiate post-traumatic degeneration, making early detection of injury imperative for timely surgical or pharmaceutical interventions. Cationic (positively-charged) CT contrast agents detect loss of cartilage proteoglycans (PGs) more sensitively than anionic (negatively-charged) or non-ionic (non-charged, i.e., electrically neutral) agents. However, degeneration related loss of PGs and increase in water content have opposite effects on the diffusion of the cationic agent, lowering its sensitivity. In contrast to cationic agents, diffusion of non-ionic agents is governed only by steric hindrance and water content of cartilage. We hypothesize that sensitivity of an iodine(I)-based cationic agent may be enhanced by simultaneous use of a non-ionic gadolinium(Gd)-based agent. We introduce a quantitative dual energy CT technique (QDECT) for simultaneous quantification of two contrast agents in cartilage. We employ this technique to improve the sensitivity of cationic CA4+ (q =+4) by normalizing its partition in cartilage with that of non-ionic gadoteridol. The technique was evaluated with measurements of contrast agent mixtures of known composition and human osteochondral samples (n = 57) after immersion (72 h) in mixture of CA4+ and gadoteridol. Samples were arthroscopically graded and biomechanically tested prior to QDECT (50/100 kV). QDECT determined contrast agent mixture compositions correlated with the true compositions (R2= 0.99, average error = 2.27%). Normalizing CA4+ partition in cartilage with that of gadoteridol improved correlation with equilibrium modulus (from ρ = 0.701 to 0.795). To conclude, QDECT enables simultaneous quantification of I and Gd contrast agents improving diagnosis of cartilage integrity and biomechanical status.

authors

  • Bhattarai, Abhisek
  • Honkanen, Juuso T J
  • Myller, Katariina A H
  • Prakash, Mithilesh
  • Korhonen, Miitu
  • Saukko, Annina E A
  • Virén, Tuomas
  • Joukainen, Antti
  • Patwa, Amit N
  • Kröger, Heikki
  • Grinstaff, Mark W
  • Jurvelin, Jukka S
  • Töyräs, Juha

publication date

  • April 13, 2018

Research

keywords

  • Cartilage, Articular
  • Contrast Media
  • Knee Injuries
  • X-Ray Microtomography

Identity

Scopus Document Identifier

  • 85045249694

Digital Object Identifier (DOI)

  • 10.1007/s10439-018-2013-y

PubMed ID

  • 29654384

Additional Document Info

volume

  • 46

issue

  • 7