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Netherlands Institute for Innovative Ocular Surgery
Research and development of ophthalmic surgical techniques
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H.A Maaskantstraat 31, 3071 MJ Rotterdam, The Netherlands
tel +31 (0)10 485 4882, fax +31 (0)10 485 2419

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    Posterior lamellar keratoplasty (PLK): on-line course
       Abstract
       Chapter 1: Introduction
       Chapter 2: Optical visualization of dissection depth during surgery
       Chapter 3: A strategy to minimize interface haze
       Chapter 4: PLK through a 9.0 mm scleral incision
       Chapter 5: PLK through a 5.0 mm scleral tunnel incision
       Chapter 6: Preparation of donor tissue
       Chapter 7: Peri-operative topical and systemic therapy
       Chapter 8: Clinical results
       Chapter 9: Conclusions and recommendations
       References
 Surgical training
 Products and instruments

Chapter 8: Clinical results

Posterior lamellar keratoplasty procedures were performed on a total of 21 patients. In 16 patients (Series I), a posterior lamellar disc was transplanted through a 9 mm scleral incision (see Chapter 4), and through a 5 mm scleral tunnel incision in five patients (Series II, see Chapter 5). All but one patients underwent uneventful surgeries. In one eye, a perforation of the recipient, peripheral stromal bed occurred during lamellar pocket dissection, and the procedure was converted into a penetrating keratoplasty.

In all but one eyes that had a posterior lamellar keratoplasty, the posterior transplant remained in situ throughout the postoperative period, with complete apposition of the donor-to-recipient tissues at the stromal interface. In one eye, a residual layer of visco elastic was present at the donor-to-recipient interface, causing the posterior transplant to slowly detach within the first week. In this patient, a penetrating keratoplasty was performed one month after the initial surgery. All other transplants cleared with a normal, transient degree of inflammation, and biomicroscopy showed minimal interface scarring, and a normal healing response at the posterior stromal wound edges .

Results of Series I

6 months 12 months
BCVA 0.25 to 0.8 0.25 to 1.0
Astigmatism 1.8 D ± 0.7 D 1.5 D ± 0.8 D
Pachymetry n.d. 0.49 ± 0.09 mm
ECD n.d. 2520 ± 340 cells-mm2

Results of Series II

Since this Series is rather small, and the follow-up period is less than a year, it may not be justified to draw any conclusions from the present data. However, it is my clinical impression that the astigmatism is further reduced by performing the posterior transplantation through a 5 mm scleral tunnel incision. In all but one patients a useful visual acuity, 0.5 or more, was reached within the first month. In one patient, the posterior transplant shows a fold in the area of the optical axis, reducing the visual outcome to 0.1.

Complications

  • In one eye, a perforation during surgery, so that the procedure was converted into a penetrating keratoplasty
  • In one eye, redidual visco-elastic at the donor-to-recipient stromal interface, causing a slow detachment of the posterior lamellar disc.
  • Four eyes (3 eyes in Series I and 1 eye in Series II) showed clinically significant interface opacification, that may require future re-transplantation.
  • One eye that previously underwent multiple posterior segment surgeries, developed a severe corneal ulcer four months after surgery. During the four months postoperative time period the transplant was clear and in position, and the development of the ulcer may not have been directly related to the presence of the posterior transplant.
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