Deep Trephination Allows High Rates of Successful Pneumatic Dissection for DALK Independent of Surgical Experience

Cornea. 2019 May;38(5):645-647. doi: 10.1097/ICO.0000000000001881.


Purpose: To evaluate the relationship between surgical experience and the success rate of pneumatic dissection for deep anterior lamellar keratoplasty (DALK) using deep trephination.

Methods: A noncomparative case series evaluating the first 10 consecutive keratoconic eyes without deep stromal scarring, operated by 8 surgeons of 3 different experience levels, was conducted; there were a total of 80 patients. Standardized DALK was performed, including deep trephination 450 to 550 μm in depth and 9 mm in diameter, pneumatic dissection, removal of the stroma, and transplantation of a 9-mm partial-thickness anterior lamellar graft. The success rate of pneumatic dissection correlated with surgical experience.

Results: Pneumatic dissection succeeded in 7, 7, 8, and 9 cases of 10 cases in the first group of 4 inexperienced surgeons (under 10 previous keratoplasties of any kind); in 9 and 10 of 10 cases in the second group of 2 relatively experienced surgeons (under 100 keratoplasties); and in 10 and 8 of 10 cases in the third group of 2 very experienced surgeons (more than 1000 previous keratoplasties). No difference between the groups was found to be statistically significant with the χ test (P > 0.05).

Conclusions: The standardized DALK technique using a deep trephination allows high success rates of pneumatic dissection even for surgeons inexperienced in keratoplasty.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Clinical Competence
  • Corneal Stroma / surgery*
  • Corneal Transplantation / methods*
  • Dissection / methods*
  • Female
  • Humans
  • Keratoconus / surgery*
  • Male
  • Middle Aged
  • Retrospective Studies
  • Visual Acuity