CPT® Code 61304

An exploratory supratentorial craniectomy or craniotomy is a surgical procedure performed to investigate potential defects or injuries within the supratentorial region of the brain. The supratentorial area is defined as the portion of the brain located above the tentorium cerebelli, which is a fold of dura mater that separates the cerebrum's frontal and occipital lobes from the cerebellum. This procedure involves either a craniectomy, where a section of the skull is removed, or a craniotomy, where the skull is opened but the bone may be replaced. During a craniectomy, the surgeon creates scalp flaps and drills burr holes in the skull, then uses a saw or craniotome to cut the bone between these holes, allowing for the removal of a large bone flap. In contrast, a craniotomy involves incising the scalp and lifting the scalp, bone, and dural flaps to gain access to the cerebrum. The primary goal of this exploratory procedure is to examine the brain for any abnormalities without performing any definitive surgical intervention. After the exploration, the dural flap is carefully repositioned and sutured to prevent cerebrospinal fluid leakage, and the bone flap is either reattached or, in some cases, the defect is filled with materials such as bone wax or silicone. The procedure concludes with the closure of the fascia, muscle, and scalp in layers to ensure proper healing.