May Be Caused by

Air bubbles

Arterial collaterals

Cholesteatoma

Endometriosis

Eosinophilic ureteritis

Granulomas

Leukoplakia

Malacoplakia

Multiple calculi

Papillomatosis

Polyp

Schistosomiasis haematobium

Squamous metaplasia

Strictures

Submucosal hemorrhage

Thrombus

Transitional cell carcinoma

Tuberculosis

Ureteritis cystica

Varicosities

Venous collaterals