title: Effect of fiber structure on dialysate flow profile and hollow-fiber hemodialyzer reliability: CT perfusion study.
abstract: BACKGROUND
  Uniform dialysate distributions in hollow-fiber hemodialyzers facilitate effective solute removal, and the fiber structure inside hemodialyzers plays a significant role in determining dialysate flow distribution and dialysis efficiency. The authors analyzed the effects of undulated fibers on dialysate flow profiles and hemodialyzer reliability using a perfusion CT technique.
  
  
  METHODS
  Using a multi-detector row CT unit, perfusion studies were performed on two different types of hemodialyzers: (A) straight fiber configuration; (B) undulated fiber configuration (wavy-shaped fibers). Deconvolution theory was used for image processing to derive dialysate flows, dialysate volumes, and mean transit time distributions. Three-dimensional perfusion maps for the two types of hemodialyzers were reconstructed using high resolution images and these parameters were compared at hemodialyzer midsections.
  
  
  RESULTS
  Dialysate maldistributions were observed in both types of hemodialyzer. However, dialysate flow distributions were more uniform in the undulated-fiber hemodialyzer, whereas more complex flow distributions developed in straight-fiber hemodialyzer. Reliability as determined using intraclass correlation coefficients was markedly higher for the hemodialyzer containing undulated fiber (0.968 vs. 0.496 for type A and type B, respectively).
  
  
  CONCLUSIONS
  The undulated-fiber type was found to have more uniform, consistent dialysate flow profiles. It is believed that this type of hemodialyzer will be found helpful for measurement and prescription of the delivered hemodialysis dose due to its better consistency.
authors.affiliation: Interdisciplinary Program in Bioengineering Major, Seoul National University, Seoul - Republic of Korea.
authors.forename: J C
authors.initials: JC
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: H-C
authors.initials: HC
authors.lastname: Kim
authors.forename: E
authors.initials: E
authors.lastname: Kang
authors.forename: K G
authors.initials: KG
authors.lastname: Kim
authors.forename: H C
authors.initials: HC
authors.lastname: Kim
authors.forename: B G
authors.initials: BG
authors.lastname: Min
authors.forename: C
authors.initials: C
authors.lastname: Ronco
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D015314:Dialysis Solutions; D004867:Equipment Design; D007091:Image Processing, Computer-Assisted; D008422:Materials Testing; D008567:Membranes, Artificial; D008968:Molecular Conformation; D010477:Perfusion; D006435:Renal Dialysis / Q000295:instrumentation* / Q000592:standards; D015203:Reproducibility of Results; D012212:Rheology / Q000379:methods*; D013997:Time Factors; D014057:Tomography, X-Ray Computed
chemical_list: D001672:Biocompatible Materials; D015314:Dialysis Solutions; D008567:Membranes, Artificial