CPT® Code 78730

Add-On Code

A urinary bladder residual study, identified by CPT® Code 78730, is a diagnostic procedure that evaluates the efficiency of bladder emptying and identifies potential obstructions or dysfunctions within the urinary system. This study employs scintigraphy, a technique that utilizes a radiolabeled isotope tracer to visualize the bladder's function. The procedure can be conducted using two primary methods: direct radionucleotide cystography (DRC) and indirect radionucleotide cystography (IRC). In DRC, the bladder is catheterized, and the radiolabeled isotope tracer is instilled along with fluid to expand the bladder. Following this, the patient is asked to void, and the volume of urine remaining in the bladder is measured or calculated. Alternatively, in IRC, the tracer is injected into the circulatory system, allowing for imaging of the kidneys, ureters, and bladder, including assessments of residual urine after voiding. Proper patient preparation is essential for both methods, which may involve catheterization or intravenous line insertion. A gamma camera is utilized to capture images of the bladder at designated intervals, converting the emitted radioactive energy into visual data. The physician then interprets the results and generates a comprehensive written report detailing the findings of the study.