Frequently Asked Questions and Answers about Craniotomy

A craniotomy is a surgery performed by neurosurgeons to treat various conditions affecting the brain. In simple terms, craniotomy means a ‘hole in the head’. In this procedure, a piece of the skull is removed for the surgeon to access the brain beneath, for the treatment of a variety of neurological disorders. A craniotomy may be either small or large depending on the severity of the problem. Neurosurgeons or other specialists who perform this surgical procedure need to correctly document the same in the patient’s medical records. Opting for medical billing services from an established medical billing company can help simplify the documentation process.

Here are some frequently asked questions and answers about Craniotomy –

Q: What is Craniotomy and what does the procedure involve?

A: A craniotomy is an opening of the skull – the bone of the head – that encloses the brain and its surrounding structures. Generally, in this procedure the bone is reserved and later fixed into place at the end of the surgical procedure. However, if the bone is left out of the head (done for various reasons in some procedures) the term more appropriately used is a craniectomy. This procedure is done if swelling occurs after the brain surgery or if the skull bone flap cannot be replaced for other reasons.

Generally, a craniotomy may be either small or large depending on the severity of the problem. The openings done during the procedure can be performed at various locations of the skull, depending on the area of the skull being targeted. In order to access the skull, an opening in the skin of the scalp is performed initially. This skin or any underlying tissue like muscle is then retracted or flapped over to expose the underlying skull. The location, size and shape of the opening will generally depend on the type/size of tumor and the other needs of the case. In most cases, the actual craniotomy is normally done by first performing “burr holes” which are then joined together by a different cutting tool. This allows the removal of a large piece of bone which is then further reserved. At the end of the procedure, the bone is fixed into place (by various metal devices or plates), prior to the flap being closed.

Q: What are the reasons for performing a craniotomy?

A: A craniotomy may be done for a variety of reasons like –

  • Diagnose, remove, or treat brain tumors
  • Clip or repair an aneurysm
  • Remove blood or blood clots from a leaking blood vessel
  • Treat hydrocephalus
  • Treat epilepsy
  • Repair skull fractures
  • Repair a tear in the membrane lining the brain (dura mater)
  • Remove an arteriovenous malformation (AVM – an abnormal mass of blood vessels)
  • Remove an arteriovenous fistula (AVF)
  • Relieve intracranial pressure (pressure within the brain) by removing damaged or swollen areas of the brain (caused by traumatic injury or stroke)
  • Implant stimulator devices to treat movement disorders such as Parkinson disease or dystonia
  • Drain an infected pus-filled pocket (abscess)

In addition to the above, a craniotomy also allows a surgeon to inspect the brain for abnormalities, perform a biopsy or relieve pressure inside the skull.

Q: What are the different types of craniotomy?

A: There are different types of craniotomies that vary in size and complexity and these include-

  • Extended bi-frontal craniotomy – This is a traditional skull base approach used to target difficult tumors toward the front of the brain.
  • Minimally invasive supra-orbital “Eyebrow” craniotomy – In this type, neurosurgeons make a small incision within the eyebrow to access tumors in the front of the brain or pituitary tumors.This minimally-invasive procedure may be part of the treatment for Rathke’s cleft cysts, skull base tumors and some pituitary tumors.
  • Retro-Sigmoid “Keyhole” craniotomy – Neurosurgeons may use this approach to remove tumors like meningiomas and acoustic neuromas (vestibular schwannomas).
  • Orbitozygomatic craniotomy – This type is typically used to treat lesions that are too complex for removal by more minimally invasive approaches.
  • Translabyrinthine craniotomy–This procedure involves making an incision in the scalp behind the ear, then removing the mastoid bone and some of the inner ear bone (specifically the semicircular canals which contain receptors for balance).

Q: What are the potential risks associated with the procedure?

A: As any surgical procedure will have its own set of complications, brain surgery risk may depend upon the specific location of the brain that the operation will affect. Some of the general complications include – bleeding, infection of the lungs (pneumonia), unstable blood pressure, seizures, muscle weakness, leakage of the cerebrospinal fluid, brain swelling, blood clots and the risks of general anesthesia. In addition, there may be some other rare complications like – memory problems, paralysis, speech difficulty, coma and abnormal balance or coordination that directly relate to the specific places in the brain.

Q: How is Craniotomy performed?

A: The procedure may vary from one person to another, depending on the condition treated. Craniotomy is generally performed under general anesthesia. The surgeon will make an incision (cut) in the scalp, a skin flap is peeled back, burr holes are drilled in the skull, and then a piece of bone (“bone flap”) is cut out to reveal the brain underneath. The bone flap will be removed and saved. The thick outer covering of the brain directly underneath the bone (dura mater) will be separated from the bone and carefully cut to open it to expose the brain, securing it with retractors. Once the brain surgery is performed, the retractors are removed and the dura is closed with sutures. The bone flap is replaced and secured with plates and screws, which remain permanently to provide support. The muscles and skin are replaced and sutured; a drain may be inserted to prevent fluid retention. A soft adhesive bandage is placed over the incision.

The procedure may take about 4-6 hours. After the completion of the procedure, patients will be taken to the recovery room wherein their vital signs will be clearly monitored. Depending on the type of surgery performed, patients may be given steroid medications (to control swelling) and anticonvulsant medications (to prevent seizures).

Neurosurgery medical billing and coding can be challenging as it involves using several codes. Neurosurgeons and other specialists who perform craniotomy must use the relevant medical codes to bill for the procedure. CPT codes for used to report craniotomy include –

  • 61304 – Craniectomy or craniotomy, exploratory; supratentorial
  • 61305 – Craniectomy or craniotomy, exploratory; infratentorial (posterior fossa)
  • 61312 – Craniectomy or craniotomy for evacuation of hematoma, supratentorial; extradural or subdural
  • 61313 – Craniectomy or craniotomy for evacuation of hematoma, supratentorial; intracerebral
  • 61314 – Craniectomy or craniotomy for evacuation of hematoma, infratentorial; extradural or subdural
  • 61315 – Craniectomy or craniotomy for evacuation of hematoma, infratentorial; intracerebellar
  • 61320 – Craniectomy or craniotomy, drainage of intracranial abscess; supratentorial
  • 61321 – Craniectomy or craniotomy, drainage of intracranial abscess; infratentorial
  • 61322 – Craniectomy or craniotomy, decompressive, with or without duraplasty, for treatment of intracranial hypertension, without evacuation of associated intraparenchymal hematoma; without lobectomy
  • 61323 – Craniectomy or craniotomy, decompressive, with or without duraplasty, for treatment of intracranial hypertension, without evacuation of associated intraparenchymal hematoma; with lobectomy
  • 61343 – Craniectomy, suboccipital with cervical laminectomy for decompression of medulla and spinal cord, with or without dural graft
  • 61345 – Other cranial decompression, posterior fossa
  • 61458 – Craniectomy, suboccipital; for exploration or decompression of cranial nerves
  • 61460 – For section of 1 or more cranial nerves
  • 61510 – Craniectomy, trephination, bone flap craniotomy; for excision of brain tumor, supratentorial, except meningioma
  • 61512 – Craniectomy, trephination, bone flap craniotomy; for excision of meningioma, supratentorial
  • 61514 – Craniectomy, trephination, bone flap craniotomy; for excision of brain abscess, supratentorial
  • 61516 – Craniectomy, trephination, bone flap craniotomy; for excision or fenestration of cyst, supratentorial
  • 61518 – Craniectomy for excision of brain tumor, infratentorial or posterior fossa; except meningioma, cerebellopontine angle tumor, or midline tumor at base of skull
  • 61519 – Craniectomy for excision of brain tumor, infratentorial or posterior fossa; meningioma
  • 61520 – Craniectomy for excision of brain tumor, infratentorial or posterior fossa; cerebellopontine angle tumor
  • 61521 – Craniectomy for excision of brain tumor, infratentorial or posterior fossa; midline tumor at base of skull
  • 61522 – Craniectomy, infratentorial or posterior fossa; for excision of brain abscess
  • 61524 – Craniectomy, infratentorial or posterior fossa; for excision or fenestration of cyst
  • 61526 – Craniectomy, bone flap craniotomy, transtemporal (mastoid) for excision of cerebellopontine angle tumor;
  • 61530 – Craniectomy, bone flap craniotomy, transtemporal (mastoid) for excision of cerebellopontine angle tumor; combined with middle/posterior fossa craniotomy/craniectomy
  • 61533 – Craniotomy with elevation of bone flap; for subdural implantation of an electrode array, for long-term seizure monitoring
  • 61534 – Craniotomy with elevation of bone flap; for excision of epileptogenic focus without electrocorticography during surgery
  • 61535 – Craniotomy with elevation of bone flap; for removal of epidural or subdural electrode array, without excision of cerebral tissue (separate procedure)
  • 61536 – Craniotomy with elevation of bone flap; for excision of cerebral epileptogenic focus, with electrocorticography during surgery (includes removal of electrode array)
  • 61537 – Craniotomy with elevation of bone flap; for lobectomy, temporal lobe, without electrocorticography during surgery
  • 61538 – Craniotomy with elevation of bone flap; for lobectomy, temporal lobe, with electrocorticography during surgery
  • 61539 – Craniotomy with elevation of bone flap; for lobectomy, other than temporal lobe, partial or total, with electrocorticography during surgery
  • 61540 – Craniotomy with elevation of bone flap; for lobectomy, other than temporal lobe, partial or total, without electrocorticography during surgery
  • 61541 – Craniotomy with elevation of bone flap; for transection of corpus callosum
  • 61543 – Craniotomy with elevation of bone flap; for partial or subtotal (functional) hemispherectomy
  • 61544 – Craniotomy with elevation of bone flap; for excision or coagulation of choroid plexus
  • 61545 – Craniotomy with elevation of bone flap; for excision of craniopharyngioma
  • 61546 – Craniotomy for hypophysectomy or excision of pituitary tumor, intracranial approach
  • 61548 – Hypophysectomy or excision of pituitary tumor, transnasal or transseptal approach, nonstereotactic
  • 61566 – Craniotomy with elevation of bone flap; for selective amygdalohippocampectomy
  • 61567 – For multiple subpial transections, with electrocorticography during surgery
  • 61570 – Craniectomy or craniotomy; with excision of foreign body from brain
  • 61571 – Craniectomy or craniotomy; with treatment of penetrating wound of brain
  • 61575 – Transoral approach to skull base, brain stem or upper spinal cord for biopsy, decompression or excision of lesion;
  • 61576 – Transoral approach to skull base, brain stem or upper spinal cord for biopsy, decompression or excision of lesion; requiring splitting of tongue and/or mandible (including tracheostomy)

Immediately after the procedure, patients will be taken to a recovery room for observation before being taken to the intensive care unit (ICU) to be closely monitored. Medications will be given to reduce swelling. The recovery period will vary depending upon the type of procedure done and the type of anesthesia given. However, it is important for patients to carefully follow the recovery guidelines. Most patients are instructed to avoid engaging in strenuous activities, consuming alcohol and tobacco products and driving until cleared for these activities by their treatment team.

With the high specificity of the new CPT codes, neurosurgeons or other specialists who perform craniotomy needs to correctly document the different types of procedures performed. Partnering with an experienced medical coding company is a great option for physicians to ensure accurate and timely claim submissions.