1. q5 Urinary Incontinence

A 55 years old lady presents to the clinic with complaints of leakage of urine on coughing and straining, confirmed by a bladder diary. A urine dipstick is normal. On examination, there is grade 3 cystocele. She has been doing pelvic floor exercises. She is not relieved of her symptoms and is now requesting surgery.  What other investigation is recommended before surgery in this patient?