The purpose of this study is to find out which pain relief method works better for people having video-assisted thoracoscopic surgery. We will compare two techniques: thoracic paravertebral block (TPVB), a numbing injection near the spine, and intrathecal morphine (ITM), a small dose of morphine injected into the spinal fluid. We want to see if ITM works as well as TPVB in reducing the need for pain medicine during the first 24 hours after surgery. People in the study will get either TPVB or ITM before going to sleep for surgery, use a patient-controlled pain pump after surgery, and have their pain scores, medicine use, recovery, and possible side effects checked for up to 30 days after surgery.