The surgery went well and took the patient to PACU. After that I went back to OR to get ready for my next patient and pull out the lens for the next case. That time I realized that we had two patients with the same last name and immediately panicked then called the doctor to let him know that I accidently switched the lens. My mistake was even though I did the time out, correct patient, correct eye site, I did not check the patients name but just checked the last name only. It turned out that the two patients that we had were related with the same last name such as mother who is 92 years old and her daughter 64. Moreover, mistake happened due to mix-up of the patients order of schedule and doctor forgot to bring his booklet to verify the lens number of each patient. I gave the wrong lens to my patients’ mother which had to be 22.3 but I gave the 23.3. However, when surgeon checked his computer on measurements that he did it was correct but the mistake was the technician entered 22.3 whereas the doctors order was 23.2. this time I was off the hook but never again this mistake is going to happened to me