title: Evaluation of early anatomical changes following canaloplasty with anterior segment spectral-domain optical coherence tomography and ultrasound biomicroscopy.
abstract: OBJECTIVE
  To analyse structural changes in conjunctiva, sclera and Schlemm's canal (SC) following canaloplasty with optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM).
  
  
  METHODS
  Fifteen patients undergoing canaloplasty were included in this prospective study. AS-OCT images were acquired pre- and 1, 7, 30 and 90 days postoperatively. UBM was performed 3 months postoperatively. The surgical site was evaluated for the presence of SC, transscleral filtration, a scleral lake and the visibility of intra-Schlemm-sutures. The height and width of SC were measured at the 3 and 9 o'clock limbus position.
  
  
  RESULTS
  After canaloplasty, SC was detectable with AS-OCT in 93% of the patients on day 1. The increase in height was higher than that in width (height: +369%, p = 0.0004, width: +152%, p = 0.002). IOP was negatively correlated to SC's width 1 week postoperatively (r = -0.63, p = 0.04) and to SC's height until 3 months (r = -0.66, p = 0.02) postoperatively. Using UBM, a reflection of the traction sutures indicated SC's position in all patients. Transscleral filtration was found in all patients using AS-OCT, demonstrating a peak 1 week postoperatively. At 3 months, a scleral lake could be visualized in 50% and 83% of patients using AS-OCT and UBM, respectively.
  
  
  CONCLUSIONS
  AS-OCT offers a high resolution for imaging superficial conjunctival areas and SC after canaloplasty, whereas UBM is capable of detecting deeper structures such as scleral lakes or intra-canal-sutures. The results imply a correlation of the dilation of SC with the IOP-lowering effect and an early pronounced transscleral filtration following canaloplasty.
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Fuest
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Kuerten
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Koch
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Jakob
authors.initials: J
authors.lastname: Becker
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Thalia
authors.initials: T
authors.lastname: Hirsch
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Walter
authors.affiliation: Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
authors.forename: Niklas
authors.initials: N
authors.lastname: Plange
mesh_terms: D000368:Aged; D003228:Conjunctiva / Q000000981:diagnostic imaging*; D017889:Exfoliation Syndrome / Q000601:surgery; D005260:Female; D018463:Filtering Surgery / Q000379:methods*; D005902:Glaucoma, Open-Angle / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D016850:Limbus Corneae / Q000000981:diagnostic imaging*; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D011446:Prospective Studies; D012590:Sclera / Q000000981:diagnostic imaging*; D013524:Surgical Flaps; D041623:Tomography, Optical Coherence; D014065:Tonometry, Ocular; D014129:Trabecular Meshwork / Q000601:surgery*
keywords: bleb; canaloplasty; glaucoma; intraocular pressure