Isolated progressive visual loss after coiling of paraclinoid aneurysms

Abstract

Background and purpose: The proximity of the paraclinoid segment of the internal carotid artery to the visual pathways may result in visual deficits when patients present with aneurysms in this segment. Although surgical clip ligation of these aneurysms has been the standard of care for decades, the advent of coil embolization has permitted endovascular therapy in those aneurysms with favorable dome-to-neck ratios. Although immediate nonprogressive visual loss after coil embolization of paraclinoid aneurysms has been well described, isolated progressive visual loss immediately or shortly following coil embolization, to our knowledge, has not. We have identified 8 patients who experienced progressive loss of vision, unassociated with any other neurologic deficits, developing immediately or shortly after apparently uncomplicated coil embolization of a paraclinoid aneurysm.

Materials and methods: This study is a retrospective case series of 8 patients seen at 4 separate academic institutions. Inpatient and outpatient records were examined to determine patient demographics, previous ocular and medical history, and ophthalmic status before endovascular embolization. In addition, details of the primary endovascular therapy and subsequent surgical and nonsurgical interventions were recorded. Follow-up data, including most recent best-corrected visual acuity, postoperative course, and duration of follow-up were documented.

Results: Eight patients developed progressive visual loss in 1 or both eyes immediately or shortly after apparently uncomplicated coiling of a paraclinoid aneurysm. MR imaging findings suggested that the visual loss was most likely caused by perianeurysmal inflammation related to the coils used to embolize the aneurysm, enlargement or persistence of the aneurysm despite coiling, or a combination of these mechanisms. Most patients experienced improvement in vision, 2 apparently related to treatment with systemic corticosteroids.

Conclusion: Patients in whom endovascular treatment of a paraclinoid aneurysm is contemplated should be warned about the potential for both isolated nonprogressive and progressive visual loss in 1 or both eyes. Patients in whom progressive visual loss occurs may benefit from treatment with systemic corticosteroids.

Fig 1.

Case 4. A 52-year-old woman with progressive visual loss in the left eye beginning 5 days following coiling of a left paraclinoid aneurysm. A, Preoperative MR imaging: T2-weighted axial image shows an aneurysm arising from the paraclinoid portion of the left ICA. B, Preoperative MR imaging: T1-weighted axial image following administration of gadolinium shows marked enhancement of the aneurysm. C, Preoperative MR imaging: T1-weighted coronal image following administration of gadolinium shows marked enhancement of the aneurysm. D, Five days after coiling: T2-weighted axial MR image shows a heterogeneous signal intensity from within the aneurysm, consistent with coil packing. E, Five days after coiling: T1-weighted axial MR image following administration of gadolinium shows that most of the aneurysm no longer enhances; however, there is generalized irregular enhancement surrounding it. F, Five days after coiling: T1-weighted coronal MR image following administration of gadolinium shows a thin layer of irregular enhancement either in the wall of the aneurysm or in adjacent tissue. G, Six months after coiling: T2-weighted axial MR image shows that the aneurysm is slightly larger (1–2 mm) than before coiling. H, Six months after coiling: T1-weighted axial MR image following administration of gadolinium shows areas of persistent slight enhancement around the margin of the coiled aneurysm. I, Six months after coiling: T1-weighted coronal MR image following administration of gadolinium shows a thin margin of irregular enhancement around the coiled aneurysm.

Fig 2.

Case 5. A 53-year-old man with progressive visual loss in the left eye beginning 24 hours following coiling of a left paraclinoid aneurysm. T1-weighted axial (A) and coronal (B) MR images show irregular enhancement, suggesting recanalization of the aneurysm as well as mildly diminished flow within the left cavernous and supraclinoid ICA, thought to be related to mass effect from the partially occluded aneurysm.

Fig 3.

Case 8. A 71-year-old woman with progressive visual loss in the right eye beginning 2 weeks following coiling of a right paraclinoid aneurysm. A, Conventional angiogram following endovascular embolization demonstrates compaction of coils at the anterior portion of the aneurysm. B, Automated static perimetry 8 weeks postcoiling reveals a field defect in the right eye and a minimal superior temporal defect in the left eye. C, Eleven weeks after coiling, the visual field (automated static perimetry) of the right eye shows minimal worsening and there is now a more significant superior temporal defect in the visual field of the left eye. D, Thirty-nine weeks after coiling, the visual field (automated static perimetry) of the right eye shows improvement and there is minimal change in the superior temporal defect in the visual field of the left eye. E, Automated static perimetry 54 weeks after the coiling procedure reveals an improved superior and inferior arcuate scotoma on the right side. The left eye reveals a subtle superotemporal defect.