In the current study, it is hypothesized that adding low dose atracurium to lidocaine, bupivacaine and hyaluronidase mixture would provide an early onset of akinesia and favorable surgical condition in per-caruncular peribulbar anesthesia for high myopes undergoing phacoemulsification Initially, informed consents from the eligible patients will be obtained. Preoperatively, the axial length of the enrolled patients will be measured by ultrasound biometry and the presence of staphyloma was identified by B-scan.