TY - JOUR
T1 - Biomechanics of LASIK Flap and SMILE Cap
T2 - A Prospective, Clinical Study
AU - Khamar, Pooja
AU - Shetty, Rohit
AU - Vaishnav, Ravish
AU - Francis, Mathew
AU - Nuijts, Rudy M. M. A.
AU - Roy, Abhijit Sinha
N1 - Funding Information:
Supported in part by the Indo-German Science and Technology Center, India.
Publisher Copyright:
© 2019 Slack Incorporated. All rights reserved.
PY - 2019/5
Y1 - 2019/5
N2 - PURPOSE: To analyze the acute effect of flap cut in laser in situ keratomiteusis (LASIK) eyes and cap cut in small incision tenticule extraction (SMILE) eyes on corneal biomechanical properties of patients undergoing surgery.METHODS: This was a prospective, interventional, longitudinal case series. Forty-eight eyes of 24 patients underwent contrataterat LASIK and SMILE. Corvis ST (Oculus Optikgerate GmbH, Wetztar, Germany) measurements were performed preoperatively, intraoperativety, and 1 week and 1 month after surgery. In LASIK eyes, the flap was cut but not lifted before intraoperative measurements. In SMILE eyes, the cap and side cut incision were made before intraoperative measurement. Thirty biomechanical variables were analyzed, assuming multiple comparisons.RESULTS: In LASIK and SMILE eyes, 36.7% and 13.3% of the total number of variables detected biomechanical weakening after flap and cap cuts (P = .02), respectively. Further, 13.3% and 40% of the total variables detected no biomechanical changes after flap and cap cut, respectively (P = .03). These acute biomechanical effects of flap and cap cuts did not influence 1-week and 1-month measurements (P > .05) because both LASIK and SMILE eyes showed similar biomechanical weakening.CONCLUSIONS: Flap and cap cuts induced biomechanical weakening in patient corneas. The flap caused more weakening than the cap intraoperatively. However, biomechanical differences between LASIK and SMILE eyes were similar after removal of tissue and ongoing wound healing.
AB - PURPOSE: To analyze the acute effect of flap cut in laser in situ keratomiteusis (LASIK) eyes and cap cut in small incision tenticule extraction (SMILE) eyes on corneal biomechanical properties of patients undergoing surgery.METHODS: This was a prospective, interventional, longitudinal case series. Forty-eight eyes of 24 patients underwent contrataterat LASIK and SMILE. Corvis ST (Oculus Optikgerate GmbH, Wetztar, Germany) measurements were performed preoperatively, intraoperativety, and 1 week and 1 month after surgery. In LASIK eyes, the flap was cut but not lifted before intraoperative measurements. In SMILE eyes, the cap and side cut incision were made before intraoperative measurement. Thirty biomechanical variables were analyzed, assuming multiple comparisons.RESULTS: In LASIK and SMILE eyes, 36.7% and 13.3% of the total number of variables detected biomechanical weakening after flap and cap cuts (P = .02), respectively. Further, 13.3% and 40% of the total variables detected no biomechanical changes after flap and cap cut, respectively (P = .03). These acute biomechanical effects of flap and cap cuts did not influence 1-week and 1-month measurements (P > .05) because both LASIK and SMILE eyes showed similar biomechanical weakening.CONCLUSIONS: Flap and cap cuts induced biomechanical weakening in patient corneas. The flap caused more weakening than the cap intraoperatively. However, biomechanical differences between LASIK and SMILE eyes were similar after removal of tissue and ongoing wound healing.
KW - INCISION LENTICULE EXTRACTION
KW - LASER-ASSISTED LASIK
KW - IN-SITU KERATOMILEUSIS
KW - CORNEAL BIOMECHANICS
KW - VIVO
KW - PRK
U2 - 10.3928/1081597X-20190319-01
DO - 10.3928/1081597X-20190319-01
M3 - Article
C2 - 31059582
SN - 1081-597X
VL - 35
SP - 324
EP - 332
JO - Journal of Refractive Surgery
JF - Journal of Refractive Surgery
IS - 5
ER -