Christopher Wirbelauer — Page 2

PubMedDate not supplied

Experimental imaging of intracorneal ring segments with optical coherence tomography.

PURPOSE: To investigate the imaging of corneal structures with optical coherence tomography (OCT) after implantation of intracorneal ring segments (ICRS). METHODS: In an experimental study with six porcine eyes, qualitative and quantitative imaging with corneal OCT using a wavelength of 1310 nm after implantation of ICRS was performed. The optical results were compared with light microscopy of the histological sections. RESULTS: In corneal OCT, the ICRS revealed marked hyporeflective intrastromal areas, which correlated well with macroscopic and microscopic findings. Corneal OCT enabled precise images of the incision depth for the implantation of ICRS, and the exact intrastromal segment position. CONCLUSIONS: Noncontact slit lamp-adapted corneal optical coherence tomography could be employed to clinically monitor corneal changes after implantation of ICRS, evaluate the depth of the segments to correlate refractive changes, and quantify the stromal wound healing response.

Animals↗

PubMedDate not supplied

Intraoperative optical coherence pachymetry during laser in situ keratomileusis--first clinical experience.

PURPOSE: To investigate intraoperative optical coherence pachymetry during laser in situ keratomileusis (LASIK). METHODS: In an initial clinical evaluation, three patients with myopia and myopic astigmatism were studied. Corneal thickness was assessed with optical pachymetry based on low-coherence interferometry during LASIK. RESULTS: The attempted mean spherical equivalent refraction was -5.70 +/- 2.00 D with a mean calculated stromal ablation depth of 95 +/- 18 microm. Intraoperative optical coherence pachymetry was reproducible in all patients during the different stages of LASIK, demonstrating a mean flap thickness of 141 +/- 30 microm with a residual corneal stroma of 274 +/- 24 microm at the end of the laser ablation. The immediate postoperative corneal thickness revealed marked swelling. CONCLUSIONS: This initial clinical evaluation proved that intraoperative optical coherence pachymetry may be an important safety feature for monitoring flap and residual stromal thickness during LASIK. It may be particularly helpful in the effort to avoid iatrogenic corneal ectasia in patients with thin corneas, higher refractive corrections, and LASIK enhancements.

Adult↗