title: Intraoperative Optical Coherence Tomography Using the RESCAN 700: Preliminary Results in Collagen Crosslinking.
abstract: OBJECTIVE
  To compare the penetration of riboflavin using a microscope-integrated real time spectral domain optical coherence tomography (ZEISS OPMI LUMERA 700 and ZEISS RESCAN 700) in keratoconus patients undergoing accelerated collagen crosslinking (ACXL) between epithelium on (epi-on) and epithelium off (epi-off).
  
  
  METHODS
  Intraoperative images were obtained during each of the procedures. Seven keratoconus patients underwent epi-on ACXL and four underwent epi-off ACXL. A software tool was developed using Microsoft.NET and Open Computer Vision (OpenCV) libraries for image analysis. Pre- and postprocedure images were analyzed for changes in the corneal hyperreflectance pattern as a measure of the depth of riboflavin penetration.
  
  
  RESULTS
  The mean corneal hyperreflectance in the epi-on group was 12.97 ± 1.49 gray scale units (GSU) before instillation of riboflavin and 14.46 ± 2.09 GSU after AXCL (P = 0.019) while in the epi-off group it was 11.43 ± 2.68 GSU and 16.98 ± 8.49 GSU, respectively (P = 0.002). The average depth of the band of hyperreflectance in the epi-on group was 149.39 ± 15.63 microns and in the epi-off group it was 191.04 ± 32.18 microns.
  
  
  CONCLUSIONS
  This novel in vivo, real time imaging study demonstrates riboflavin penetration during epi-on and epi-off ACXL.
authors.affiliation: Department of Cornea & Refractive Surgery, Narayana Nethralaya 121/C, Chord Road, 1st "R" Block, Rajajinagar, Bangalore, Karnataka 560 010, India.
authors.forename: Natasha
authors.identifier: 0000-0001-5331-2110
authors.initials: N
authors.lastname: Pahuja
authors.affiliation: Department of Cornea & Refractive Surgery, Narayana Nethralaya 121/C, Chord Road, 1st "R" Block, Rajajinagar, Bangalore, Karnataka 560 010, India.
authors.forename: Rohit
authors.initials: R
authors.lastname: Shetty
authors.affiliation: Department of Cornea & Refractive Surgery, Narayana Nethralaya 121/C, Chord Road, 1st "R" Block, Rajajinagar, Bangalore, Karnataka 560 010, India.
authors.forename: Chaitra
authors.identifier: 0000-0001-8392-7159
authors.initials: C
authors.lastname: Jayadev
authors.affiliation: Department of Ophthalmology, Maastricht University Medical Center, Netherlands.
authors.forename: Rudy
authors.identifier: 0000-0003-2218-9660
authors.initials: R
authors.lastname: Nuijts
authors.affiliation: Forus Health Pvt. Ltd, No. 2234, 23rd Cross, Banashankari 2nd Stage, Bangalore 560070, India.
authors.forename: Bharath
authors.initials: B
authors.lastname: Hedge
authors.affiliation: Department of Cataract & Refractive Lens Surgery, Narayana Nethralaya, 121/C, Chord Road, 1st "R" Block Rajajinagar, Bangalore, Karnataka 560 010, India.
authors.forename: Vishal
authors.initials: V
authors.lastname: Arora
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000627:therapeutic use; D003315:Cornea / Q000000981:diagnostic imaging / Q000473:pathology*; D063171:Corneal Pachymetry; D003432:Cross-Linking Reagents / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D008297:Male; D011859:Radiography; D041623:Tomography, Optical Coherence
chemical_list: D003432:Cross-Linking Reagents; D003094:Collagen