What are the causes behind a low capacity bladder. test shows 6 oz, is leakage point. ?

Anatomy: I am not a urologist, but intuition tells me that the cause of low capacity bladder is due to anatomical variation. HOWEVER, if the problem is recent, then I ask what is causing the sudden frequent urination and low capacity? Is it a space occupying lesion? I would suggest continued follow-up with a urologist for testing: ultrasound, cystoscopy, etc.