CPT® Code 78630

Cerebrospinal fluid (CSF) flow imaging, designated by CPT® Code 78630, is a diagnostic procedure that utilizes scintigraphy along with a radiolabeled isotope tracer to visualize the movement of CSF within the central nervous system. This imaging technique is crucial for identifying abnormalities in CSF flow, which can include conditions such as communicating and non-communicating hydrocephalus, as well as fistulas that may develop between a CSF reservoir, known as a cistern, and the nasal cavity or ear. The CSF is produced in the lateral ventricles of the brain and flows through various anatomical structures, including the foramen of Monro into the third ventricle, and subsequently into the fourth ventricle via the aqueduct of Sylvius. From the fourth ventricle, the CSF enters the subarachnoid spaces through the medial foramen of Magendie and the lateral foramina of Luschka. The movement of CSF is facilitated by several mechanisms, including bulk flow, which occurs from areas of high pressure to those of lower pressure, as well as pulsatile motion that is influenced by the cardiac cycle of the cerebral arteries. During the procedure, a radiolabeled isotope tracer is introduced into the CSF through a lumbar puncture, and the patient is positioned on an imaging table with a gamma camera placed over the area of interest. Scanning is conducted at predetermined intervals, capturing the radioactive energy emitted, which is then transformed into a visual image for analysis. This procedure specifically focuses on the cisterns, as indicated by the use of Code 78630, while a different code, 78635, is applied when the ventricles are the primary focus of the imaging study. The physician is responsible for interpreting the results of the imaging study and providing a comprehensive written report detailing the findings.