title: Vascularization of coralline versus synthetic hydroxyapatite orbital implants assessed by gadolinium enhanced magnetic resonance imaging.
abstract: OBJECTIVE
  To evaluate the fibrovascular in-growth of coralline and synthetic hydroxyapatite orbital implants by reporting the enhancement patterns on Gadolinium-Dietilen triamin penta acetic acid (Gad-DTPA) enhanced magnetic resonance imaging (MRI).
  
  
  METHODS
  The medical records of 26 patients who had undergone primary or secondary orbital implantation between April 2008 and February 2011 were reviewed. T1 weighted Gad-DTPA MRI was performed between 5 and 12 months (mean 9.2 ± 5.9 months) after implantation and graded as follows to evaluate the fibrovascular in-growth of the implants; grade 1 (rim enhancement), grade 2 (peripheral foci of enhancement, not including the center), grade 3 (central, non-homogenous enhancement), grade 4 (central, homogenous enhancement) and grade 5 (central, intense enhancement).Results were analysed according to vascularization patterns on Gad-DTPA MRI.
  
  
  RESULTS
  Central vascularization patterns (grade 3, 4 or 5) were seen 62.5% of coralline orbital implants and 46.1% of synthetic orbital implants. Central fibrovascular in-growth of the coralline implants were found significantly more than synthetic implants (p < 0.05). Central vascularization of coralline implants with primary implantation was 75% and with secondary implantation was 50%. Synthetic orbital implantation with primary surgery demonstrated 66.6% and synthetic orbital implantation with secondary surgery demonstrated 26.6% central vascularization pattern. In both natural coralline and synthetic implants, primary orbital implantation was demonstrated significantly better fibrovascular in-growth than secondary implantation (p < 0.05). Two patients with synthetic orbital implants had dehiscence that was repaired by using autogenous fascia lata.
  
  
  CONCLUSIONS
  In both coralline and synthetic orbital implants, central vascular in-growth was observed much more with primary orbital implantation. This study indicates that coralline HA orbital implants significantly supply more rapid and homogenous vascularization than synthetic implants.
authors.affiliation: Department of Ophthalmology, Bolu Gerede State Hospital , Bolu , Turkey .
authors.forename: Tuba
authors.initials: T
authors.lastname: Celik
authors.forename: Dilek
authors.initials: D
authors.lastname: Yuksel
authors.forename: Mustafa
authors.initials: M
authors.lastname: Kosker
authors.forename: Remzi
authors.initials: R
authors.lastname: Kasim
authors.forename: Saban
authors.initials: S
authors.lastname: Simsek
mesh_terms: D000293:Adolescent; D000328:Adult; D001672:Biocompatible Materials; D002516:Ceramics; D002648:Child; D003238:Connective Tissue / Q000502:physiology; D003287:Contrast Media; D017886:Durapatite / Q000138:chemical synthesis; D015353:Eye Enucleation; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D006882:Hydroxyapatites; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018919:Neovascularization, Physiologic / Q000502:physiology*; D009915:Orbit / Q000601:surgery*; D020273:Orbital Implants; D016062:Porosity; D055815:Young Adult
chemical_list: D001672:Biocompatible Materials; D003287:Contrast Media; D006882:Hydroxyapatites; C119955:coralline hydroxyapatite; D017886:Durapatite; D019786:Gadolinium DTPA
keywords: Coralline; gadolinium; hydroxyapatite; magnetic resonance imaging; orbital implants