«Catch» the displacement of the WEB!

• 77-yo male patient with hypertension, multi-vessel arteriopathy, multiple coronary stents, assuming daily dual antiplatelet therapy. Scheduled for left hemicolectomy for a malignant colon polyp.
• During a 12-month MRI follow-up brain MRI exam due to an unruptured aneurysm of bifurcation of the left middle cerebral artery, a dimensional increase of the aneurysm was detected (8x6 mm vs 6x5 mm).
• Endovascular treatment of the aneurysm was planned, and the patient was scheduled for the procedure.

• Under general anesthesia, through a 8F right femoral arterial access, a coaxial system consisting of a guide catheter over an intermediate catheter was positioned in the petrous segment of the left internal carotid artery.
• The aneurysm sac was catheterized with a VIA27 microcatheter and an attempt to position a WEB 8x3 mm was made, which failed due to the excessive size of the device that, once positioned, covered the origin of the division branches of MCA.

• The device was retrieved and a new WEB 7x2 mm was positioned within the aneurysm sac. Subsequent checks showed correct positioning of the device. Detachment was then performed.
• After the detachment, the WEB spontaneously dislocated inside the sac with subsequent patency of the neck.

• We decided to adjust the position of the WEB by catching it and pulling it back at the neck of the aneurysm with a snare.
• Final angiogram checks showed complete exclusion of the aneurysm from circulation with contrast stasis within the device, which appeared correctly positioned.

• Upon awakening, no new neurological symptoms occurred and a control CT scan excluded complications.
• After one month from procedure, outpatient consultation was performed—good post-operative course with complete recovery of daily activities. No headache.
• Next follow-up with an angiographic study at six months from discharge…

Conclusion

• Optimal WEB sizing is essential for successful aneurysm treatment, reduction of costs, and avoidance of complications.
• With the growing experience and more frequent use of WEB devices, neurointerventionists should be increasingly aware of possible bailout techniques in cases of device migration or dislocation.

References

1. Elliot Pressman et al., «Validity of Woven EndoBridge Sizing Based on the Device-to-Aneurysm Volume Ratio», Interventional Neuroradiology, 14 november 2024, https://doi.org/10.1177/15910199241298327
2. Krishna Amuluru et al., «Adjustment of Malpositioned Woven EndoBridge Device Using Gooseneck Snare: Complication Management Technique», Neurointervention 16, fasc. 3 (1 november 2021): 275–79, https://doi.org/10.5469/neuroint.2021.00318

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