1892 CE, Francis Sedgwick Watson, in International Clinics, J. B. Lippincott Company; Volume I, page #269:In order to obtain a view of the interior of the bladder it is customary to pass into its cavity spatulæ with solid blades or wire retractors to hold the sides of the wound apart and to distend the bladder. These spatulæ or retractors, usually three in number, one on each side and one above, require to be held by assistants, and, being thus out of the immediate control of the operator’s own hands, are liable to become displaced and to interfere with his manipulations. Solidâ€bladed spatulæ, moreover, should not be used, because they cover up a considerable surface of the bladder.
