Atracurium Versus Atracurium and Magnesium Sulphate As Adjuvants to Local Anesthetic

Who May Qualify: - Patients undergoing elective cataract surgery (phacoemulsification and intraocular lens implantation). Patients aged 20-80 years. Both sexes. ASA physical status I\&II. Who Should NOT Join This Trial: \- Refusal of the patient to participate in the study. Any disorder of neuromuscular system known from history or clinical examination e.g., Guillarian barre syndrome, Myasthenia gravies and Myopathies. Patients are known to have a history of fits. Patients on medication known to interact with neuromuscular blocking drugs as antipyretics (aminoglycosides and tetracyclines), antiarrhythmic (quinidine). Local sepsis. Coagulation abnormalities (INR\>1.4). High myopia with axial length more than 30 mm or less than 21. Mentally retarded patients and failure of proper communication as in deafness. Morbidly obese patients (BMI\>40). Patients with glaucoma (increased IOP\>20mmgh). Patients with history of hypersensitivity to study drugs. Very dense or very soft cataract . Always talk to your doctor about whether this trial is right for you.