5 ON-LABEL USE (ILLUSTRATIVE CASES)
Abstract
The Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial helped define the on-label indications for use of the Pipeline Embolization Device (Covidien, Medtronic, Irvine, CA). 1 Indications include large or giant aneurysms of the petrous, cavernous, clinoidal, and/or ophthalmic internal carotid artery (ICA) segments (i.e., proximal to the posterior communicating artery [PCoA]) with a diameter of ≥ 10 mm and a neck diameter of ≥ 4 mm. Pipeline was approved by the Food and Drug Administration (FDA) in April 2011 and the next-generation Pipeline Flex was approved in February 2015. Other flow-diverting stents with the CE mark of approval include the Silk (Balt Extrusion; Montgomery, France), Surpass (Stryker Neurovascular, Fremont, CA), and FRED (Microvention, Terumo; Somerset, NJ). Surpass and FRED are undergoing trials for FDA approval in the United States.
5.1 Case 1: H3165540
5.1.1 Clinical Presentation
The patient, a 50-year-old woman, came to our attention while undergoing a workup for transient left-sided hearing loss. She underwent magnetic resonance imaging (MRI) of her brain, which incidentally demonstrated a 7-mm flow void within the R middle cerebral artery (MCA). She was then referred for computed tomography angiography, which revealed a 12-mm irregularly shaped aneurysm involving the cavernous and ophthalmic segments of the right internal carotid artery (ICA). She had no history of headache or neurological deficit apart from the transient hearing loss.
5.1.2 Radiologic studies
Cerebral angiography demonstrated a multilobulated, broad-based aneurysm extending from the distal cavernous segment of right ICA into the ophthalmic segment ICA. The dome measuregd 12 mm in maximum diameter with a neck diameter of 7 mm. The aneurysmal segment of artery involved greater than 180 degrees of the vessel circumference. The ophthalmic artery was demonstrated to be of cavernous origin and remote to the aneurysm. There was a normal variant early bifurcation of the MCA with a normal M1 branch and an accessory anterior temporal artery branch. In venous phase, there was no contrast stagnation within the aneurysm ( Fig. 5.1a–d).
5.1.3 Diagnosis
Large, unruptured, wide-necked multilobulated aneurysm of the right distal cavernous and ophthalmic ICA without involvement of the ophthalmic artery.
5.1.4 Treatment
Equipment
Standard 4F access and 4F catheter (VERT; Cook Medical; Bloomington, IN).
0.035” hydrophilic guidewire (GLIDEWIRE; Terumo; Somerset, NJ).
6F shuttle sheath catheter (KSAW; Cook Medical).
0.058” Navien catheter (Covidien, Irvine, CA).
0.027” Marksman microcatheter (Covidien).
0.014” Synchro II microwire (Stryker Neurovascular, Fremont, CA).
Pipeline Embolization Device (Covidien); 4.75 mm × 18 mm.
Exchange length Synchro II guidewire (Stryker Neurovascular).
6F closure device (Angio-Seal; St. Jude′s Medical, St. Paul, MN).
Intravenous heparin.
Description
The patient was loaded with aspirin and clopidogrel and taken electively to the angiography suite. The patient was intubated, and using Seldinger technique a 6F KSAW Shuttle catheter sheath was introduced. As per our protocol, the patient was then heparinized to an activated clotting time (ACT) of greater than 250 and less than 350, which was maintained throughout the entire procedure.
The KSAW Shuttle was then taken up into the proximal cervical segment of the right ICA. Introduced through this was a Navien 0.058 catheter with an internalized Marksman microcatheter and 0.14 Synchro II microwire. This coaxial construct was then used to pass the Navien catheter tip into the cavernous segment of the ICA. Angiography including three-dimensional (3D) workstation reconstructions was used to align our working angle views. Measurements were taken at the landing zones intended for the Pipeline device, demonstrating arterial calibers of 3.7 mm distally and 4.3 mm proximally with an intervening maximum diameter of 4.8 mm ( Fig. 5.1e).
At this point, the Marksman catheter was advanced into the M1 segment on the right. A premeasured 4.75 mm × 18 mm Pipeline Embolization Device was placed into the Marksman catheter and then deployed across the neck of the aneurysm with good overlap achieved proximal and distal to the neck. A high-resolution XperCT 3D angiogram was performed which demonstrated excellent apposition of the deployed Pipeline device to the normal surrounding parent vessel walls and no evidence of endoleak.
Final branch vessel and working angle views demonstrated good flow through the normal and parent vessels, no evidence of any thromboembolic event, and early stasis of flow in the large aneurysm. Flow through the ophthalmic artery and the choroidal blush of the retina remained intact both pre– and post–device placement. The microcatheters and guide catheters were then removed and the common femoral arteriotomy was sealed with a closure device.
5.1.5 Outcome
The patient was discharged home on postoperative day 1 without complication and maintained on dual-antiplatelet therapy. Angiography at 6 months demonstrated almost total thrombosis and resolution of the aneurysm, which at this point appeared as a 0.7-mm irregularity on the sidewall of the otherwise normal-in-appearance parent vessel ( Fig. 5.1f, g). Angiography at 12 months demonstrated no residual aneurysm opacification ( Fig. 5.1g). Clopidogrel was discontinued, and aspirin was changed to 81 mg daily. Magnetic resonance angiography (MRA) obtained 2 years after treatment demonstrated stable result, and the patient was at her preoperative baseline.
5.1.6 Discussion
This patient was offered treatment for this unruptured aneurysm for several reasons. First, the aneurysm carried a 1 to 2% per year risk of rupture at minimum. 2 , 3 Second, the aneurysm was multilobulated and highly irregular in appearance which also has been shown to increase the risk of rupture. 3
Placement of a flow-diverting stent was presented to this patient as the safest and most effective treatment for several reasons. The wide neck of the aneurysm would make coil embolization or balloon-assisted coil embolization difficult to perform safely due to the risk of coil herniation into the ICA. Performing stent-assisted coil embolization may have been effective in producing thrombosis in the dome of the aneurysm; however, the affected segment of the ICA appeared to demonstrate aneurysmal irregularity spanning more than half of the circumference of the parent artery. Thus, scaffold stent-assisted coil embolization would accept a high rate of recurrence in the long term. 4 This pathologic feature called for either open microsurgical clip reconstruction or flow diversion. The wide neck of the aneurysm and the pathologic dilatation of an extensive portion of the ICA made microsurgical clip reconstruction a less attractive option due to the high risk of parent vessel stenosis, need for prolonged brain retraction, and potential progression of dilatation into previously unaffected segments.
Fortunately, the origin of the ophthalmic artery was not involved in the aneurysmal segment. Persistent anterograde flow through large vessels, in proximity to or involved in the aneurysm, counteracts the flow diversion effect of the stent and portends a high risk of residual filling of the aneurysm on follow-up imaging. 5
The ability of a flow diverting device to achieve endoluminal reconstruction of the vessel wall makes it ideal for the treatment of aneurysms involving large portions of the affected segment of the parent vessel.
5.2 Case 2: H3205881
5.2.1 Clinical Presentation
The patient was a 75-year-old woman, who presented with 2 years of progressive worsening of headaches and right-sided retro-orbital pain. She reported a 30-year smoking history, but was in otherwise excellent health. She underwent an MRI/MRA of the brain that demonstrated a 10-mm right ophthalmic ICA aneurysm. She was counseled that due to the large size of her aneurysm and her smoking history she faced a significant risk of rupture within her lifetime. Owing to her advanced age and the broad neck of the aneurysm, we recommended endovascular treatment with the Pipeline Embolization Device with coil embolization. She was started on aspirin 325 mg PO daily and clopidogrel 75 mg PO daily 1 week prior to treatment, and taken to the angiography suite for evaluation.
5.2.2 Radiologic Studies
Cerebral angiography demonstrated a 10-mm wide-necked saccular aneurysm of the ophthalmic segment of the right ICA. The neck measured 4.5 mm, while the dome measured 12 x 8 mm in maximum dimension. There was no significant stasis of contrast in the dome and filling downstream of the aneurysm appeared to be within normal limits ( Fig. 5.2a–c).
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
