To study the effects of tissue manipulation, two different techniques and tools were used for tissue separation and extraction. First, a one-tool technique was utilized in which the paddle-shaped separator (Reinstein Lenticule Separator; Malosa Medical, Elland, UK) was used to dissect the anterior and posterior surfaces and to extract by dragging out the lenticule. In contrast, the two-tool technique employed the Reinstein dissector or the needle-shaped separator of the Shroff dissector (Shroff Dissector and Opener, Double Ended; Epsilon Eye Care, Mumbai, India) to separate the anterior and posterior surfaces, followed by forceps (SMILE Lenticule Removal Forceps; Duckworth & Kent, Hertfordshire, UK) to extract the lenticule. For all other studies, the lenticular surfaces were first separated using a LASIK spatula (Seibel II Intralase Flap Lifter & Retreatment Spatula Titanium; Katena Products, Parsippany, NJ) and then extracted using forceps. When single scans and single lenticular surfaces were made, the surface of the cornea was gently stroked with the spatula to release any bubbles. Flaps created by ELITA and iFS were lifted using the LASIK spatula. The spatula was inserted under the flap near the hinge and slid across the bed to separate the flap surfaces. After the flap was lifted, the flap was placed back on the host cornea.