A bilobed anterior communicating artery (ACoA) aneurysm in an 80-year-old man with a transient ischemic attack five years prior to presentation was noted to have aneurysm growth up to 7 mm in maximal diameter on serial imaging. During an elective endovascular embolization procedure, severe tortuosity was noted at the femoral iliac junction during guide catheter access, as well as at the origin of the left common carotid artery, which shared an origin with the innominate off the aorta. The f inal guide catheter access consisted of a 90 cm length multipurpose tip shape Neuron Max 088 (Penumbra Inc, Alameda, CA, USA) guide catheter to the left distal common carotid artery over a 115 cm length Navien 058 (Covidien Neurovascular, Irvine, CA, USA) intermediate guide catheter to the left distal cervical internal carotid artery (ICA). Both guide catheters were "hubbed-out" or inserted entirely into the patient. Attempts to advance a 150 cm length SL-10 (Stryker Neurovascular, Fremont, CA) microcatheter over a wire only allowed access to the A1 segment of the left anterior cerebral artery, whereby the hub of the microcatheter was in contact with the hub of the intermediate catheter.

A 165 cm Marathon microcatheter with a distal inner diameter (ID) of 0.013" instead was advanced over a Synchro 10 guidewire (Stryker Neurovascular, Fremont, CA, USA) and access to the dome of the aneurysm was obtained (Fig. 1A). A 5 mm × 13 cm Barricade coil (Blockade Medical, Irvine, CA, USA) was then advanced easily and smoothly through the Marathon microcatheter. The pusher wire length was insufficient to completely deploy the coil, necessitating removal of the rotating hemostatic valve (RHV), and therefore the continuous flush to the microcatheter. This shorter length was sufficient to completely deploy the coil with enough pusher wire length to attach a circuit clip to electrolytically detach the coil. Detachment was also complicated by the lack of a proximal radio-opaque marker on the distal aspect of the Marathon microcatheter which by convention is located 3 cm from the most distal tip of other catheters used to deploy coils. This required additional time to slowly and carefully advance the pusher wire until detachment zone was out of the microcatheter and detachment actually occurred. Five coils in total were deployed, including a 5 mm × 13 cm, 4 mm × 7 cm, 3 mm × 6 cm, 2.5 mm × 6 cm and a 2.5 mm × 4 cm. The f inal coil was able to achieve a satisfactory occlusion grade and the microcatheter was removed without issue (Fig. 1B). The patient tolerated the procedure well and was discharged home the next day with a normal neurologic examination.

A 48-year-old man was admitted with a severe headache and subarachnoid hemorrhage in the suprasellar cistern, interhemispheric f issure, and bilateral sylvian fissures. He was found to have a 5 mm bilobed, inferiorly directed ACoA aneurysm (Fig. 2A). Using a 6-Fr Neuron guide catheter, access was obtained to the right cervical ICA. A Marathon microcatheter was advanced over a Synchro 10 guidewire to selectively catheterize the aneurysm. Upon withdrawal of the wire, there was some movement of the microcatheter tip that required adjustment of forward tension on the microcatheter. Coil embolization with a 3 mm × 6 cm and 3 mm × 4 cm Barricade coils proceeded with caution. As in the previous case, the RHV and hence continuous flush had to be removed to accommodate the complete deployment of the coils. The lack of a 3 cm distal marker on the Marathon microcatheter prolonged the detachment times since caution was necessary to avoid advancing the pusher wire out of the distal microcatheter tip. Upon placement of a third 2 mm × 4 cm coil, there appeared to be increased resistance within the microcatheter causing buckling of the microcatheter near the carotid siphon. This was presumably because of clot collecting within the microcatheter. The microcatheter was removed, and after straightening out the catheter, the undetached coil was retrieved. The microcatheter was flushed on the back table, and clot emerged from the microcathter (Fig. 3). Another Marathon microcatheter was then advanced into the aneurysm and coil embolization was completed without complication (Fig. 2B). The patient tolerated the procedure well and was discharged home after an uneventful hospital stay with a normal neurologic examination.

A 48-year-old female with a strong history of familial cerebral aneurysms was found to have a 4 mm saccular aneurysm with a broad neck at the right ICA terminus on a screening MRA of the brain. The patient was consented for an elective stent-assisted coil embolization of the aneurysm (Fig. 4) given the family history a ruptured cerebral aneurysms and patient preference. On the day of the procedure, the right common carotid artery was selected with a 6-Fr Neuron guide catheter through a right common femoral artery access. A 4.5 × 20 mm Neuroform EZ stent (Stryker, Kalamazoo, MI, USA) was deployed from the A1 segment into the ICA. A Marathon microcatheter was used to catheterize the ICA terminus aneurysm through the stent and a 3 mm × 6 cm and 2 mm × 4 cm Target Ultrasoft coils (Stryker, Kalamazoo, MI, USA) were deployed through the Marathon catheter without complication. During deployment of each coil, the RHV and thus continuous flush was temporally removed to accommodate the Styrker electrolytic detachment device (Fig. 5). After the coils were detached from the pusher wire, the electrolytic detachment device was removed and the RHV was replaced restoring the continuous flush before the pusher wire was withdrawn from the catheter to avoid clot formation within the microcatheter. The patient tolerated the procedure well and later discharged home neurologically intact.