BRANCH RETINAL ARTERY OCCLUSION AFTER INTERNAL CAROTID ARTERY ANGIOPLASTY AND STENTING Peter A. Karth, MD,* Sameer Siddiqui, BA, MA,* Donald Garbett, MD,† Kimberly E. Stepien, MD*
Purpose: A 67-year-old man with an embolic branch retinal artery occlusion occurring as a complication of internal carotid artery stenting, despite the use of a distal filter cerebral protection device was reported. Methods: Observational case report. One patient case is included in this case report. Results: The patient developed a branch retinal arterial occlusion with visible emboli 24 hours after a carotid angioplasty and stenting procedure and was found to have multiple anastomoses between the external carotid artery and ophthalmic artery as a result of carotid stenosis. He required a second, emergent angioplastic procedure. Conclusion: External carotid-ophthalmic arterial anastomoses can act as a pathway for emboli to travel from the internal carotid artery to the retinal circulation, resulting in retinal arterial occlusions, despite the use of cerebral protective devices. Ophthalmologists and interventional radiologists should be aware of these factors, especially as the number of percutaneous carotid artery stenting procedures continues to increase. RETINAL CASES & BRIEF REPORTS 0:1–4, 2013
branches of the left external carotid artery (ECA) (Figure 1), and no anterograde flow from the left ICA to the left ophthalmic artery was observed. Severe stenosis was noted in the proximal cervical and petrous portions of the left ICA. Balloon angioplasty and stenting of the proximal cervical ICA was performed without apparent complication. A distal filter SpiderFX embolic protection device (ev3 Endovascular, Inc, Plymouth, MN) was deployed in the distal cervical ICA throughout the procedure; no proximal protection device was used. Brisk anterograde flow was restored to the middle cerebral artery; however, the ophthalmic artery continued to fill only by means of the anastomosis from the ECA with retrograde flow. The patient remained on heparin after the procedure. Twenty-four hours after the procedure, the patient noted vision changes in the left eye. Examination by interventional radiologists revealed a superior confrontational visual field defect in the left eye. Emergency angioplasty was performed. Flow to the left ophthalmic artery was provided only by small collateral vessels from the left middle meningeal artery without distal retinal perfusion (Figure 1). Angioplasty of the previously identified blockage within the petrous segment of the left ICA was performed, restoring anterograde blood flow to the left ophthalmic artery. Ophthalmology was consulted after this procedure. Ophthalmologic history was not significant. Snellen visual acuity was 20/25+2 in both eyes. A mild afferent pupillary defect was seen in the left eye. Confrontational visual field testing revealed a superior field defect approaching fixation in the left eye. The findings from the intraocular pressure and anterior segment examination were unremarkable. The result of dilated fundus examination revealed 2 inferior quadrants of retinal whitening consistent with an inferior
From the *Eye Institute/Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin; and †Department of Radiology, Aurora St. Luke’s Medical Center, Milwaukee, Wisconsin.
Case Report A 67-year-old man with multiple vasculopathic risk factors (aortic stenosis, hypertension, diabetes mellitus Type 2, hypercholesterolemia, obesity, and obstructive sleep apnea) was found to have high-grade stenosis of his left internal carotid artery (ICA) as a result of atherosclerotic disease on carotid Doppler imaging. Stenosis was found at the proximal left ICA via diagnostic angiography. He was at a high risk for surgical carotid endarterectomy because of his severe cardiac disease. Therefore, the interventional radiology service performed percutaneous transfemoral carotid stenting to recanalize the stenotic left ICA. During the initial angiography, the left ophthalmic artery was seen to fill in a retrograde fashion by means of the anastomotic connections with None of the authors have any conflicting interests to disclose. Supported by an unrestricted grant from the Research to Prevent Blindness. All research for this report was conducted at the Medical College of Wisconsin, Milwaukee, WI. Reprint requests: Peter A. Karth, MD, Eye Institute/Department of Ophthalmology, Medical College of Wisconsin, 925 N 87th St, Milwaukee, Wisconsin 53226; e-mail: [email protected]
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RETINAL CASES & BRIEF REPORTS´ 2013 VOLUME 0 NUMBER 0
Fig. 1. Angiogram of a patient undergoing left carotid artery stenting in whom a left branch retinal artery occlusion occurred. The angiogram shows collateral vessels (A) from the left external carotid circulation to the ophthalmic artery (not visualized here because of the lack of flow). Other arterial vasculature seen includes anterior division of middle meningeal (B), posterior division middle meningeal (C), middle meningeal (D), superficial temporal (E), middle meningeal (F), maxillary (G), external carotid (H), and catheter tip (X).
branch retinal artery occlusion (Figure 2). Color fundus photographs and fluorescein angiography (Figure 2) showed multiple intraarterial emboli and decreased arterial flow. Optical coherence tomography (Figure 2) showed thickening and increased reflectivity of the inner inferior retina. Imaging was believed to be consistent with a branch retinal artery occlusion involving the two inferior quadrants.
Discussion In normal circulation, the common carotid arteries bifurcate into the internal and external carotid arteries. The internal carotid arteries give rise to the ophthalmic arteries; the external carotid arteries give rise to the extracerebral circulation. With long-standing carotid stenosis, collateral vessels from the external carotid circulation to internal carotid branches may form to reestablish perfusion.1 These anastomoses are sometimes seen providing flow to the ophthalmic artery during angiography.
A potential complication of carotid artery stenting is retinal vessel occlusion caused by emboli or intimal disturbance. To prevent such complications, the current standard of care uses cerebral protective devices (CPD) to prevent the spread of large emboli. Currently, several different CPD are used. A distal filter device was used in our case. Distal filters are a wire mesh, basketlike device placed downstream from the stenosis and typically block particles larger than 70 mm.2 An advantage of a distal filter device is that it allows uninterrupted blood flow during the procedure; however, the catheter must be threaded through the stenosis before deployment of the distal filter.3 With typical placement, these devices do not block emboli flowing through vascular collaterals that may arise proximal to the occlusion. A study conducted by Vos et al4 found that retinal embolization occurred in 6 of 118 patients (4%) undergoing carotid artery stenting with distal filter CPD, of whom 2 were symptomatic (1.7%). A similar study5 showed retinal emboli in 5 of 33 stenting procedures (15%) using a distal CPD; 2 of those had additional small retinal infarcts. The mean rate of embolization per carotid stenting procedure has been reported as 74 particles per stenotic lesion.6 Fortunately, of all embolic material produced, few are large enough to cause retinal damage; it is emboli larger than 20 mm that typically cause symptomatic retinal artery occlusions in carotid stenting.5 Embolization causing retinal arterial occlusion despite the use of CPD has been reported in the literature. Islam et al7 described a rare case of dual embolization. A symptomatic ipsilateral embolic retinal arterial occlusion and a cerebellar embolization was observed after carotid artery stenting using a distal filter CPD. Anastomosis were seen linking the meningeal artery with the ophthalmic artery and the occipital artery with the vertebral artery. These authors suggested the protection of the ECA with a CPD during ICA stenting to prevent retinal artery occlusion in the presence of anastomoses.7 Yamasaki et al8 reported a branch retinal artery occlusion with carotid artery stenting using a distally placed CPD. Lee et al9 reported two cases of retinal artery occlusions with carotid stenting but did not comment on the use of CPDs. In our case, the ophthalmic artery was supplied by anastomoses from branches of the ECA including the middle meningeal artery, anterior deep temporal artery, infraorbital artery, and superficial temporal artery. Before the second procedure, there was no blood flow from the ICA into the ophthalmic artery because of the blockage in the petrous portion of the ICA; therefore, collaterals from the ECA were the only route of flow to the ophthalmic artery. We believe that emboli flowed through the left ECA, both reducing
Copyright ª by Ophthalmic Communications Society, Inc. Unauthorized reproduction of this article is prohibited.
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BRAO AFTER CAROTID ARTERY STENTING
Fig. 2. Ophthalmic images of a patient undergoing carotid artery stenting in whom a branch retinal artery occlusion occurred. A. Fundus photographs of the left eye showing intraarterial emboli and inferior retinal whitening in the inferior two retinal quadrants. B. Fluorescein angiography of the left eye showing decreased flow to the inferior retinal vasculature. C. Optical coherence tomographic images of the left eye showing increased thickness of the inner retina in the inferior retina.
flow through the anastomoses and allowing emboli to reach the retina. Emboli may have been released during the initial procedure that eventually lodged in the retinal vasculature, or a loosened atherosclerotic plaque may have dislodged after the initial procedure. Although a distal filter CPD was placed in the ICA, turbulent flow may have carried emboli to the ECA and its downstream anastomosis, resulting in the occlusion. Use of a CPD placed to also protect the ECA and its downstream collaterals may have blocked these emboli. Current common treatments of embolic retinal artery occlusions include maneuvers to lower intraocular pressure and digital massage; however, no therapy has been conclusively proven to be efficacious.10 More recently, intravascular thrombolytic agents have been used; however, this technique is still being evaluated.10
Conclusion This case highlights the ophthalmologic complications possible with carotid artery stenting. External carotid ophthalmic arterial anastomosis can act as a pathway of emboli to the retinal circulation, causing vision loss. Furthermore, as not all blood flow is shielded by CPDs, retinal emboli can occur during
stenting procedures. Ophthalmologists and interventional radiologists should be aware of these factors, especially as the number of percutaneous carotid artery stenting procedures continue to increase. Key words: anastomosis, branch retinal artery occlusion, carotid artery angioplasty, carotid artery stenting, retinal emboli. References 1. Henderson RD, Eliasziw M, Fox AJ, et al. Angiographically defined collateral circulation and risk of stroke in patients with severe carotid artery stenosis. Stroke 2000;31:128–132. 2. Siewiorek GM, Wholey MH, Finol EA. In vitro performance assessment of distal protection devices for carotid artery stenting: effect of physiological anatomy on vascular resistance. J Endovasc Ther 2007;14:712–724. 3. Schneider PA, Ansel G. How do I select cerebral protection devices today? J Cardiovasc Surg (Torino) 2010;51:873–883. 4. Vos JA, Werkum MH, Bistervels JH. Retinal embolization during carotid angioplasty and stenting: periprocedural data and follow-up. Cardiovasc Intervent Radiol 2009;33:714–719. 5. Wilentz JR, Chati Z, Krafft V, Amor M. Retinal embolization during carotid angioplasty and stenting: mechanisms and role of cerebral protection systems. Catheter Cardiovasc Interv 2002;56:320–327. 6. Jordan WD, Voellinger DC, Doblar DD, et al. Microemboli detected by transcranial Doppler monitoring in patients during carotid angioplasty versus carotid endarterectomy. Cardiovasc Surg 1999;7:33–38. 7. Islam S, Manabe H, Hasegawa S, et al. Retinal embolization and cerebellar asymptomatic embolization after carotid stenting
Copyright ª by Ophthalmic Communications Society, Inc. Unauthorized reproduction of this article is prohibited.
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RETINAL CASES & BRIEF REPORTS´ 2013 VOLUME 0 NUMBER 0
using distal balloon protection. A case report. Interv Neuroradiol 2003;9:311–314. 8. Yamasaki H, Matsubara S, Sasaki I, Nagahiro S. Retinal artery embolization during carotid angioplasty and carotid artery stenting: case report. Neurol Med Chir (Tokyo) 2009;49:213–216.
9. Lee SJ, Kim SY, Kim SD. Two cases of branch retinal arterial occlusion after carotid artery stenting in the carotid stenosis. Korean J Ophthalmol 2009;23:53–56. 10. Fraser SG, Adams W. Interventions for acute non-arteritic central retinal artery occlusions. Cochrane Database Syst Rev 2009;(1):CD001989.
Copyright ª by Ophthalmic Communications Society, Inc. Unauthorized reproduction of this article is prohibited.
Purpose: A 67-year-old man with an embolic branch retinal artery occlusion occurring as a complication of internal carotid artery stenting, despite the use of a distal filter cerebral protection device was reported. Methods: Observational case report. One patient case is included in this case report. Results: The patient developed a branch retinal arterial occlusion with visible emboli 24 hours after a carotid angioplasty and stenting procedure and was found to have multiple anastomoses between the external carotid artery and ophthalmic artery as a result of carotid stenosis. He required a second, emergent angioplastic procedure. Conclusion: External carotid-ophthalmic arterial anastomoses can act as a pathway for emboli to travel from the internal carotid artery to the retinal circulation, resulting in retinal arterial occlusions, despite the use of cerebral protective devices. Ophthalmologists and interventional radiologists should be aware of these factors, especially as the number of percutaneous carotid artery stenting procedures continues to increase. RETINAL CASES & BRIEF REPORTS 0:1–4, 2013
branches of the left external carotid artery (ECA) (Figure 1), and no anterograde flow from the left ICA to the left ophthalmic artery was observed. Severe stenosis was noted in the proximal cervical and petrous portions of the left ICA. Balloon angioplasty and stenting of the proximal cervical ICA was performed without apparent complication. A distal filter SpiderFX embolic protection device (ev3 Endovascular, Inc, Plymouth, MN) was deployed in the distal cervical ICA throughout the procedure; no proximal protection device was used. Brisk anterograde flow was restored to the middle cerebral artery; however, the ophthalmic artery continued to fill only by means of the anastomosis from the ECA with retrograde flow. The patient remained on heparin after the procedure. Twenty-four hours after the procedure, the patient noted vision changes in the left eye. Examination by interventional radiologists revealed a superior confrontational visual field defect in the left eye. Emergency angioplasty was performed. Flow to the left ophthalmic artery was provided only by small collateral vessels from the left middle meningeal artery without distal retinal perfusion (Figure 1). Angioplasty of the previously identified blockage within the petrous segment of the left ICA was performed, restoring anterograde blood flow to the left ophthalmic artery. Ophthalmology was consulted after this procedure. Ophthalmologic history was not significant. Snellen visual acuity was 20/25+2 in both eyes. A mild afferent pupillary defect was seen in the left eye. Confrontational visual field testing revealed a superior field defect approaching fixation in the left eye. The findings from the intraocular pressure and anterior segment examination were unremarkable. The result of dilated fundus examination revealed 2 inferior quadrants of retinal whitening consistent with an inferior
From the *Eye Institute/Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin; and †Department of Radiology, Aurora St. Luke’s Medical Center, Milwaukee, Wisconsin.
Case Report A 67-year-old man with multiple vasculopathic risk factors (aortic stenosis, hypertension, diabetes mellitus Type 2, hypercholesterolemia, obesity, and obstructive sleep apnea) was found to have high-grade stenosis of his left internal carotid artery (ICA) as a result of atherosclerotic disease on carotid Doppler imaging. Stenosis was found at the proximal left ICA via diagnostic angiography. He was at a high risk for surgical carotid endarterectomy because of his severe cardiac disease. Therefore, the interventional radiology service performed percutaneous transfemoral carotid stenting to recanalize the stenotic left ICA. During the initial angiography, the left ophthalmic artery was seen to fill in a retrograde fashion by means of the anastomotic connections with None of the authors have any conflicting interests to disclose. Supported by an unrestricted grant from the Research to Prevent Blindness. All research for this report was conducted at the Medical College of Wisconsin, Milwaukee, WI. Reprint requests: Peter A. Karth, MD, Eye Institute/Department of Ophthalmology, Medical College of Wisconsin, 925 N 87th St, Milwaukee, Wisconsin 53226; e-mail: [email protected]
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Copyright ª by Ophthalmic Communications Society, Inc. Unauthorized reproduction of this article is prohibited.
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RETINAL CASES & BRIEF REPORTS´ 2013 VOLUME 0 NUMBER 0
Fig. 1. Angiogram of a patient undergoing left carotid artery stenting in whom a left branch retinal artery occlusion occurred. The angiogram shows collateral vessels (A) from the left external carotid circulation to the ophthalmic artery (not visualized here because of the lack of flow). Other arterial vasculature seen includes anterior division of middle meningeal (B), posterior division middle meningeal (C), middle meningeal (D), superficial temporal (E), middle meningeal (F), maxillary (G), external carotid (H), and catheter tip (X).
branch retinal artery occlusion (Figure 2). Color fundus photographs and fluorescein angiography (Figure 2) showed multiple intraarterial emboli and decreased arterial flow. Optical coherence tomography (Figure 2) showed thickening and increased reflectivity of the inner inferior retina. Imaging was believed to be consistent with a branch retinal artery occlusion involving the two inferior quadrants.
Discussion In normal circulation, the common carotid arteries bifurcate into the internal and external carotid arteries. The internal carotid arteries give rise to the ophthalmic arteries; the external carotid arteries give rise to the extracerebral circulation. With long-standing carotid stenosis, collateral vessels from the external carotid circulation to internal carotid branches may form to reestablish perfusion.1 These anastomoses are sometimes seen providing flow to the ophthalmic artery during angiography.
A potential complication of carotid artery stenting is retinal vessel occlusion caused by emboli or intimal disturbance. To prevent such complications, the current standard of care uses cerebral protective devices (CPD) to prevent the spread of large emboli. Currently, several different CPD are used. A distal filter device was used in our case. Distal filters are a wire mesh, basketlike device placed downstream from the stenosis and typically block particles larger than 70 mm.2 An advantage of a distal filter device is that it allows uninterrupted blood flow during the procedure; however, the catheter must be threaded through the stenosis before deployment of the distal filter.3 With typical placement, these devices do not block emboli flowing through vascular collaterals that may arise proximal to the occlusion. A study conducted by Vos et al4 found that retinal embolization occurred in 6 of 118 patients (4%) undergoing carotid artery stenting with distal filter CPD, of whom 2 were symptomatic (1.7%). A similar study5 showed retinal emboli in 5 of 33 stenting procedures (15%) using a distal CPD; 2 of those had additional small retinal infarcts. The mean rate of embolization per carotid stenting procedure has been reported as 74 particles per stenotic lesion.6 Fortunately, of all embolic material produced, few are large enough to cause retinal damage; it is emboli larger than 20 mm that typically cause symptomatic retinal artery occlusions in carotid stenting.5 Embolization causing retinal arterial occlusion despite the use of CPD has been reported in the literature. Islam et al7 described a rare case of dual embolization. A symptomatic ipsilateral embolic retinal arterial occlusion and a cerebellar embolization was observed after carotid artery stenting using a distal filter CPD. Anastomosis were seen linking the meningeal artery with the ophthalmic artery and the occipital artery with the vertebral artery. These authors suggested the protection of the ECA with a CPD during ICA stenting to prevent retinal artery occlusion in the presence of anastomoses.7 Yamasaki et al8 reported a branch retinal artery occlusion with carotid artery stenting using a distally placed CPD. Lee et al9 reported two cases of retinal artery occlusions with carotid stenting but did not comment on the use of CPDs. In our case, the ophthalmic artery was supplied by anastomoses from branches of the ECA including the middle meningeal artery, anterior deep temporal artery, infraorbital artery, and superficial temporal artery. Before the second procedure, there was no blood flow from the ICA into the ophthalmic artery because of the blockage in the petrous portion of the ICA; therefore, collaterals from the ECA were the only route of flow to the ophthalmic artery. We believe that emboli flowed through the left ECA, both reducing
Copyright ª by Ophthalmic Communications Society, Inc. Unauthorized reproduction of this article is prohibited.
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BRAO AFTER CAROTID ARTERY STENTING
Fig. 2. Ophthalmic images of a patient undergoing carotid artery stenting in whom a branch retinal artery occlusion occurred. A. Fundus photographs of the left eye showing intraarterial emboli and inferior retinal whitening in the inferior two retinal quadrants. B. Fluorescein angiography of the left eye showing decreased flow to the inferior retinal vasculature. C. Optical coherence tomographic images of the left eye showing increased thickness of the inner retina in the inferior retina.
flow through the anastomoses and allowing emboli to reach the retina. Emboli may have been released during the initial procedure that eventually lodged in the retinal vasculature, or a loosened atherosclerotic plaque may have dislodged after the initial procedure. Although a distal filter CPD was placed in the ICA, turbulent flow may have carried emboli to the ECA and its downstream anastomosis, resulting in the occlusion. Use of a CPD placed to also protect the ECA and its downstream collaterals may have blocked these emboli. Current common treatments of embolic retinal artery occlusions include maneuvers to lower intraocular pressure and digital massage; however, no therapy has been conclusively proven to be efficacious.10 More recently, intravascular thrombolytic agents have been used; however, this technique is still being evaluated.10
Conclusion This case highlights the ophthalmologic complications possible with carotid artery stenting. External carotid ophthalmic arterial anastomosis can act as a pathway of emboli to the retinal circulation, causing vision loss. Furthermore, as not all blood flow is shielded by CPDs, retinal emboli can occur during
stenting procedures. Ophthalmologists and interventional radiologists should be aware of these factors, especially as the number of percutaneous carotid artery stenting procedures continue to increase. Key words: anastomosis, branch retinal artery occlusion, carotid artery angioplasty, carotid artery stenting, retinal emboli. References 1. Henderson RD, Eliasziw M, Fox AJ, et al. Angiographically defined collateral circulation and risk of stroke in patients with severe carotid artery stenosis. Stroke 2000;31:128–132. 2. Siewiorek GM, Wholey MH, Finol EA. In vitro performance assessment of distal protection devices for carotid artery stenting: effect of physiological anatomy on vascular resistance. J Endovasc Ther 2007;14:712–724. 3. Schneider PA, Ansel G. How do I select cerebral protection devices today? J Cardiovasc Surg (Torino) 2010;51:873–883. 4. Vos JA, Werkum MH, Bistervels JH. Retinal embolization during carotid angioplasty and stenting: periprocedural data and follow-up. Cardiovasc Intervent Radiol 2009;33:714–719. 5. Wilentz JR, Chati Z, Krafft V, Amor M. Retinal embolization during carotid angioplasty and stenting: mechanisms and role of cerebral protection systems. Catheter Cardiovasc Interv 2002;56:320–327. 6. Jordan WD, Voellinger DC, Doblar DD, et al. Microemboli detected by transcranial Doppler monitoring in patients during carotid angioplasty versus carotid endarterectomy. Cardiovasc Surg 1999;7:33–38. 7. Islam S, Manabe H, Hasegawa S, et al. Retinal embolization and cerebellar asymptomatic embolization after carotid stenting
Copyright ª by Ophthalmic Communications Society, Inc. Unauthorized reproduction of this article is prohibited.
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RETINAL CASES & BRIEF REPORTS´ 2013 VOLUME 0 NUMBER 0
using distal balloon protection. A case report. Interv Neuroradiol 2003;9:311–314. 8. Yamasaki H, Matsubara S, Sasaki I, Nagahiro S. Retinal artery embolization during carotid angioplasty and carotid artery stenting: case report. Neurol Med Chir (Tokyo) 2009;49:213–216.
9. Lee SJ, Kim SY, Kim SD. Two cases of branch retinal arterial occlusion after carotid artery stenting in the carotid stenosis. Korean J Ophthalmol 2009;23:53–56. 10. Fraser SG, Adams W. Interventions for acute non-arteritic central retinal artery occlusions. Cochrane Database Syst Rev 2009;(1):CD001989.
Copyright ª by Ophthalmic Communications Society, Inc. Unauthorized reproduction of this article is prohibited.
