In simple words: The doctor injects chemotherapy medicine into a small device under the skin of the scalp which is connected to a tube leading to the fluid surrounding the brain and spinal cord or directly into brain cavities. This is often done for cancers that have spread to the brain or spinal cord.

This CPT code (96542) represents the administration of chemotherapy, either single or multiple agents, into the subarachnoid space or intraventricularly via a subcutaneous reservoir.The procedure involves delivering chemotherapy drugs into the cerebrospinal fluid (CSF) surrounding the brain and spinal cord or directly into the ventricles of the brain. This method of administration is often used to treat cancers that have spread to the central nervous system, where standard intravenous or oral chemotherapy may not effectively reach the affected areas. The subcutaneous reservoir, frequently an Ommaya reservoir, is a surgically implanted device that allows for repeated drug administration without repeated lumbar punctures.

Example 1: A patient with metastatic brain cancer from lung cancer requires intraventricular chemotherapy.The physician orders chemotherapy administration via an Ommaya reservoir.Code 96542 is reported for the physician’s administration of the chemotherapy agent., A patient with leukemia has central nervous system involvement. The oncologist orders intrathecal chemotherapy via an Ommaya reservoir. The physician administers the chemotherapy, and 96542 is reported., A patient with lymphoma showing meningeal involvement undergoes intrathecal chemotherapy through an existing Ommaya reservoir.The physician oversees and orders the procedure, but the actual administration is performed by qualified nursing staff under the physician's direct supervision.Code 96542 is still reported for the physician's service.

* Complete patient history and physical examination relevant to the diagnosis and treatment.* Oncologist’s order specifying the chemotherapy regimen, dose, and route of administration (intraventricular or subarachnoid via subcutaneous reservoir).* Documentation of the placement and patency of the Ommaya reservoir (if new placement, relevant procedural codes should also be reported).* Detailed record of the chemotherapy administration, including the date, time, drug(s) administered, dosage, and any adverse reactions observed.* Verification that the patient provided informed consent for the procedure.

** This code should only be reported by the physician or other qualified healthcare professional who is responsible for the overall management of the patient's care. The actual administration of the chemotherapy may be performed by nursing staff under the physician's direction.Always ensure proper documentation to support the medical necessity of the procedure and to avoid coding errors.