Strengthen Weak Intracranial Aneurysm Coding
By David Zielske, MD, CPC, CPC-H, CPC-CARDIO, CCS, RCC
Complex procedures are performed at sites previously considered amenable only to open neurosurgical techniques. Interventions performed by these physicians include, but are not limited to: endovascular procedures such as intracranial thrombolysis, thrombectomy, angioplasty, stent placement, embolization, venous sampling; and spine procedures such as vertebroplasty, kyphoplasty, and sacroplasty. These interventions treat a myriad of diseases including embolic or atherosclerotic stroke, transient ischemic attacks (TIAs), aneurysms, pseudoaneurysms, vasospasm, arteriovenous and venous malformations, venous thrombosis, carotid cavernous or dural fistulae, epistaxis, neoplasms, traumatic bleeding or dissection, and vertebral body compression fractures. Let’s focus on embolization procedures for intracranial aneurysm therapeutic treatments.
Familiarize Yourself with Aneurysm Types
An aneurysm is an abnormal outward pouch on a blood vessel due to a weakening of the vessel wall. Neurointerventional surgeons focus on aneurysms affecting the brain or central nervous system. The most common aneurism is a berry aneurysm, which is found where an artery divides into two branches (bifurcation). Other aneurysms are fusiform (diffuse enlargement of the entire vessel) and dissecting (separations in the vessel wall layers). Intracranial aneurysms may be small in size, such as a berry aneurysm averaging 3-6 mm, or may be large, such as a giant internal carotid artery (ICA) aneurysm at 20 mm. Treatment options vary based on size, location, indications for therapy, and appearance whether dissecting, wide-mouthed, giant, berry, etc. Endovascular therapeutic options require vascular access and inflow vessels to be amenable to percutaneous techniques. This option also requires high quality imaging; training and expertise; coil-scaffolding and deployment systems; and technologically advanced wires, guides, and catheters to be available for performing these complex procedures.
Aneurysms are often found prior to rupture by computed tomography (CT) and magnetic resonance imaging (MRI) scans that may have been done for other reasons. If an aneurism is found after rupture, other therapies such as catheter directed non-thrombolytic infusions of verapamil and vasospasm balloon therapy may be necessary. Diagnostic work-up for a suspected intracranial aneurysm includes a four-vessel cerebral angiogram. Submit catheter placement and imaging codes as documented. As aneurysms occur in all age groups, the evaluation may or may not include imaging of the arch, CPT® code 75650 Angiography, cervicocerebral, catheter, including vessel origin, radiological supervision and interpretation, and cervical carotid arteries, code 75680 Angiography, carotid, cervical, bilateral, radiological supervision and interpretation. Patients younger than 30-years-old rarely have atherosclerotic vessel narrowing and images of the arch and cervical carotids may only be used as guiding shots and are not separately billable. Older patients may have significant atherosclerotic inflow stenoses, changing or limiting potential endovascular treatments. Where an aneurysm is found, it is common to find another, so complete studies of the vertebrobasilar system, CPT® code 75685 Angiography, vertebral, cervical, and/or intracranial, radiological supervision, and interpretation x 2, and carotid-cerebral circulation, CPT® code 75671 Angiography, carotid, cerebral, bilateral, radiological supervision and interpretation, are necessary to diagnose and treat the aneurysm. Often times, additional 3-D images, codes 76376 3D rendering with interpretation and reporting of computed tomography, magnetic resonance imaging, ultrasound, or other tomographic modality; not requiring image postprocessing on an independent workstation or 76377 3D rendering with interpretation and reporting of computed tomography, magnetic resonance imaging, ultrasound, or other tomographic modality; requiring image postprocessing on an independent workstation, need to be reconstructed from initial data to fully evaluate the anatomy of an aneurysm and devise a treatment plan.
Berry Treatments Vary
For berry aneurysms or other aneurysms with a narrow opening off the main artery, therapy is base vessel (e.g., common carotid artery) catheterization with a guiding sheath or catheter, through which a microcatheter can be advanced over a wire as small as 0.010 inches for placement into the aneurysm. Once in the aneurysm, correctly sized and configured coils are placed safely. Once deployed, these coils can be straight, helical, tornado-like, flower-like, or of other complex configurations. This allows aneurysm sac filling with coils for complete thrombosis and successful embolization to occur. Many coils are attached to a deployment wire for retracting if they are malpositioned. Once they are placed properly in the correct location, they can be released with great accuracy. A few coils or as many as 60 coils can be placed in one aneurysm, depending on its size. Use code 61624 Transcatheter permanent occlusion or embolization (eg, for tumor destruction, to achieve hemostasis, to occlude a vascular malformation), percutaneous, any method; central nervous system (intracranial, spinal cord) to accurately describe the placement of coils to embolize an intracranial aneurysm. Code 75894 Transcatheter therapy, embolization, any method, radiological supervision and interpretation describes the embolization procedure’s associated imaging, supervision and interpretation. Catheter placement and diagnostic imaging codes are submitted additionally as appropriate. The rules for intracranial embolization differ from other body part embolizations (i.e., non-central nervous system) because follow-up angiography, code 75898 Angiography through existing catheter for follow-up study for transcatheter therapy, embolization or infusion may be used as often as medically necessary during this procedure. Performing multiple follow-up angiograms during an intracranial embolization is common to ensure the procedure is safely performed. To use code 75898, each follow-up study and findings should be well documented for each procedure code submitted. CPT® code 75898 may only be billed once per surgical site in non-central nervous system locations. When a central nervous system embolization is performed and coded with code 61624 Transcatheter permanent occlusion or embolization (eg, for tumor destruction, to achieve hemostasis, to occlude a vascular malformation), percutaneous, any method; central nervous system (intracranial, spinal cord), this is an inpatient only procedure for Medicare (status indicator C).
Difficult aneurysms to treat are wide-mouthed aneurysms, as they have a large opening to the aneurysm of the normal vessel. If you place a coil in a wide-mouthed aneurysm, it has a tendency to float out of the aneurysm, embolize back into the native artery and potentially cause thrombosis and stroke. A special stent was developed for safe endovascular repair of wide-mouthed aneurysms. The stent is placed in the involved artery, across the segment of artery including the wide-mouthed aneurysm. The lattice-work of the stent is very fine, allowing microcatheter passage through the mesh work into the aneurysm for coil deployment. Once deployed, the coils are trapped in the aneurysm by the stent. Two commercially available stents are the Enterprise and the Neuroform stents. If placed at the same session as the embolization with coils, the stent placement is considered part of the embolization, coded using 61624, and is not billed with a separate code. When performed on non-Medicare patients at a separate session prior to the deployment of coils, the stent may be billed with the established intracranial stent placement code 61635 Transcatheter placement of intravascular stent(s), intracranial (eg, atherosclerotic stenosis), including balloon angioplasty, if performed. For Medicare, intracranial stent placement is covered only when performed for greater than or equal to 50 percent atherosclerotic stenosis. Since Feb. 2007, the hospital and physician must be part of a Class B-IDE study and the procedure must be billed with CPT® code 37799 Unlisted procedure, vascular surgery—not code 61635.
The third type of aneurysm treated using percutaneous techniques is the giant aneurysm, usually located on the internal carotid artery. Treatment is usually for evidence of distal embolization and stroke and not for the potential of rupture. A carotid test occlusion is often initially performed, CPT® code 61623 Endovascular temporary balloon arterial occlusion, head or neck (extracranial/intracranial) including selective catheterization of vessel to be occluded, positioning and inflation of occlusion balloon, concomitant neurological monitoring, and radiologic supervision and interpretation of all angiography required for balloon occlusion and to exclude vascular injury post occlusion, to determine if it is safe to permanently occlude the entire artery, including the aneurysm. If the patient passes the test occlusion, permanent treatment of the aneurysm is coded with 61624, 75894, and 75898, as would any intracranial aneurysm embolization procedure.
Other procedures performed with intracranial aneurysm embolotherapy include vasospasm balloon therapy, CPT® codes 61640 Balloon dilatation of intracranial vasospasm, percutaneous; initial vessel, 61641 Balloon dilatation of intracranial vasospasm, percutaneous; each additional vessel in same vascular family (List separately in addition to code for primary procedure), and 61642 Balloon dilatation of intracranial vasospasm, percutaneous; each additional vessel in different vascular family (List separately in addition to code for primary procedure), vasospasm infusion therapy, codes 37202 Transcatheter therapy, infusion other than for thrombolysis, any type (eg, spasmolytic, vasoconstrictive) and 75896 Transcatheter therapy, infusion, any method (eg, thrombolysis other than coronary), radiological supervision and interpretation, and intracranial arterial thrombectomy, codes 37184 Primary percutaneous transluminal mechanical thrombectomy, noncoronary, arterial or arterial bypass graft, including fluoroscopic guidance and intraprocedural pharmacological thrombolytic injection(s); initial vessel and 37185 Primary percutaneous transluminal mechanical thrombectomy, noncoronary, arterial or arterial bypass graft, including fluoroscopic guidance and intraprocedural pharmacological thrombolytic injection(s); second and all subsequent vessel(s) within the same vascular family (List separately in addition to code for primary mechanical thrombectomy procedure).
Advancements in technology, technique, expertise, and training have expanded neurointerventional surgeons’ capabilities allowing excellent treatment results for nearly all intracranial aneurysms by percutaneous methods.