Neurosurgery Coding Alert

Complex fixes must meet certain parameters.

When a patient experiences an intracranial aneurysm, the surgeon needs to think and act quickly to ensure the best outcome possible for that patient.

You will also need to use your wits and training to ensure that the correct code is chosen and filed with the payer. If you slip up, you could end up with a miscoded claim.

Help’s here: Check out this advice on intracranial aneurysm repair coding.

Know What Constitutes an Aneurysm

There is often confusion about the difference between an arteriovenous (AV) malformation and an aneurysm. An AV malformation could be any of a number of structurally abnormal blood vessel types. An aneurysm, however, occurs when arterial blood vessel wall weakens and makes it susceptible to rupture.

Know What Constitutes a Complex Aneurysm

Once you’re able to identify an aneurysm, you’ll have to determine whether it’s simple or complex. All simple aneurysms can be classified by the definition given above; complex aneurysms, however, require a little more skill and knowledge. And you’ll need to know the difference between simple and complex, because your code choice and reimbursement depend on it.

While individual payers might vary slightly, most will want the aneurysm to meet at least one of the following criteria to qualify as complex:

• The aneurysm is larger than 1.5 cm (15 mm).
• The aneurysm involved calcification at the neck of the aneurysm.
• The aneurysm incorporates normal vessels into the neck of the aneurysm.
• The aneurysm surgery requires one of the following: vessel occlusion, trapping, or cardiopulmonary bypass.

Note: This is not a definitive list of requirements for complex aneurysms. Check with your payer if you have any questions about what constitutes a complex aneurysm.

Check Out These Aneurysm Symptoms

A patient with a potential aneurysm will report to the surgeon with some obvious symptoms. These can include:

• Sudden, severe headache
• Nausea and vomiting
• Neck stiffness
• Sensitivity to light
• Loss of consciousness
• Neurological deficits
• Seizures
• Visual disturbances
• Dilated pupil/drooping eyelid

Your surgeon’s quest to determine whether the patient has an aneurysm will likely start with an evaluation and management (E/M) service that will be location-dependent; for example, you’ll code differently for an office/outpatient E/M than you would for a hospital/inpatient E/M.

After the E/M, the surgeon will likely perform a computed tomography (CT) scan and/or a magnetic resonance imaging (MRI), as well as some form of angiography. The CT will identify if there is bleeding in the brain, and the MRI will show the surgeon what the brain structures and blood vessels look like.

Use These Codes for Complex Fixes

When the surgeon performs an open complex intracranial aneurysm repair, you’ll report either 61697 (Surgery of complex intracranial aneurysm, intracranial approach; carotid circulation) or 61698 (… vertebrobasilar circulation), depending on encounter specifics. If the surgeon doesn’t repair these abnormal dilations of blood vessels in the brain, it could lead to severe complications such as subarachnoid hemorrhage, stroke, or even death.

Carotid circulation: If the aneurysm site is the carotid artery, surgery can be very complicated because of the chance that blood flow to the brain gets compromised.

Vertebrobasilar circulation: If the aneurysm site is vertebrobasilar, the surgery’s risk can be chalked up to the blood vessels involved. Remember, the vertebrobasilar system carries blood to the brainstem, cerebellum, and posterior cerebral hemispheres.

Example: A patient with a vertebral artery aneurysm is placed in a lateral position, with their head secured in a Mayfield head clamp. The surgeon performs a far-lateral craniotomy to expose the vertebrobasilar junction. They perform dissection to expose the basilar artery and its branches, and place temporary clips on the parent artery to stem bleeding. The surgeon then places permanent aneurysm clips to occlude the aneurysm neck. Postoperative evaluation shows that the surgery clipped the aneurysm without complications.

For this encounter, you’d report 61698 with I72.6 (Aneurysm of vertebral artery) appended to indicate that patient’s aneurysm.

Rely on These Codes for Simple Aneurysms

When a patient experiences a simple intracranial aneurysm, you’ll report 61700 (Surgery of simple intracranial aneurysm, intracranial approach; carotid circulation) or 61702 (… vertebrobasilar circulation), depending on encounter specifics.

Example: A patient with an aneurysm of the carotid artery is placed in a Mayfield clamp, and the surgeon performs a standard pterional craniotomy to provide access to the aneurysm. They then perform dissection through the Sylvian fissure and retract the brain tissue to improve visibility. The surgeon then places a curved aneurysm clip across the aneurysm neck. This removes the aneurysm from the blood circulation and preserves the other blood vessels.

For this encounter, you’d report 61700 with I72.0 (Aneurysm of carotid artery) appended to represent the aneurysm.

Chris Boucher, MS, CPC, Senior Development Editor, AAPC