GENERAL SCIENTIFIC SESSION 3 GENERAL SCIENTIFIC SESSION 3
Aneurysm Remnants After Coiling and Clipping: Considerations in Surgical and Endovascular Treatment Options Mandy J. Binning, MD Erol Veznedaroglu, MD Capital Institute of Neurosciences, Capital Health Systems, Trenton and Pennington, New Jersey Correspondence: Erol Veznedaroglu, MD, Two Capital Way, Ste 456, Pennington, NJ 08534. E-mail: [email protected]
Copyright © 2015 by the Congress of Neurological Surgeons.
T
he clinical significance of remnants or recurrences of treated intracranial aneurysms is not a new concern for vascular neurosurgeons. However, in the endovascular era of aneurysm treatment, there has been more focus on this problem. It should be noted, first and foremost, that not all aneurysm remnants are created equally. Although the Raymond and Roy classification system1 is widely used as a simple method to describe aneurysm remnants, the system does not have widespread clinical utility. For example, it does not indicate which patients require retreatment and which should be followed up with serial imaging. Diagrammatic classification systems fail to account for important clinical details such as rupture status, sidewall recurrences, follow-up stability, and patient comorbidities (Table). In the modern era of aneurysm treatment, remnants must be addressed in a comprehensive way on a case-bycase basis to ensure the best patient outcomes.
BACKGROUND
The 2014 CNS Annual Meeting presentation on which this article is based is available at http://bit.ly/1EO5oXR.
CLINICAL NEUROSURGERY
Although widely used, the Raymond and Roy aneurysm recurrence classification is purely illustrative (not prognostic) when it comes to which aneurysm remnants are of clinical significance or should be retreated. The classification was originally created to describe angiographic follow-up for unruptured aneurysms that were treated endovascularly. Class 1 was described as no residual aneurysm; Class 2 had angiographic filling at the neck; and Class 3 involved residual aneurysm filling anywhere beyond the neck. Although this classification is simple, it is too simple to use as any sort of guideline for treating patients. What the classification does not and was never meant to take into account are patient factors that determine whether aneurysm remnants should be treated or observed. For example, the original article by Roy et al1 described only follow-up in unruptured aneurysms. Aneurysm filling beyond the neck in a ruptured aneurysm intuitively carries a much different risk
compared with filling of an electively treated unruptured aneurysm. In addition, the degree and location of filling or recurrence within the treated aneurysm are important factors when reviewing the angiographic remnant. Sidewall filling between the coil mass and wall of the aneurysm is a more ominous sign than a 10% recurrence centrally just above the neck (Figure 1). Sidewall filling can signal an endovascular leak of sorts that can lead to a high rate of rerupture by allowing filling to reach the dome (Figure 2A-2C). In our practice, sidewall recurrences are treated expeditiously. Length of follow-up and stability of the remnant on angiographic or noninvasive imaging are also factored into whether an aneurysm remnant requires treatment. For example, an aneurysm remnant that has remained unchanged on magnetic resonance angiography and 5-year follow-up angiography is unlikely to change and rarely requires intervention (Figure 3). Finally, patients who smoke have a higher risk for aneurysm recurrence and should be observed more closely and for a longer period of time or should be treated early, depending on the other factors mentioned above.2
TREATMENT The first choice to make when addressing an aneurysm remnant is whether the aneurysm
TABLE. Angiographic and Patient Factors That Increase Risk of Aneurysm Rerupture Previously ruptured aneurysm A remnant that enlarges over time on serial imaging (magnetic resonance angiography/ angiography) A remnant that fills between the coil mass and the wall of the aneurysm toward the dome (sidewall filling) Patient is a smoker
VOLUME 62 | NUMBER 1 | AUGUST 2015 | 103
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BINNING AND VEZNEDAROGLU
FIGURE 3. A remnant from a previously ruptured but coiled superior cerebellar artery aneurysm has remained stable over 5 years and will continue to be observed.
FIGURE 1. A basilar bifurcation aneurysm was previously coiled and, on followup angiography, shows a sidewall recurrence between the coil mass and the dome.
When remnants need to be retreated, it is important to recognize that endovascular aneurysm retreatment carries a low complication rate.3 A series of 311 patients who underwent 352 retreatment procedures revealed a total risk of death or major disability of 1.13% per procedure or 1.28% per patient. Although the goal is always to provide the best possible treatment the first time, that study showed that retreatment
needs to be retreated. Although endovascular recurrences are more common, remnants can be seen in both clipped and coiled aneurysms. As discussed, a remnant located at or just above the neck carries a low risk of long-term change. It is common to follow up these remnants radiographically (Figures 3-4).
FIGURE 2. A, sidewall filling of this coiled aneurysm from Figure 1. B and C, filling of the dome of the aneurysm in Figure 1. Sidewall filling acted as an endovascular leak between the aneurysm wall and the coil mass.
104 | VOLUME 62 | NUMBER 1 | AUGUST 2015
FIGURE 4. A remnant from a previously clipped, unruptured posterior inferior cerebellar artery aneurysm has remained stable over 5 years and will continue to be observed.
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ANEURYSM REMNANTS
FIGURE 5. A, angiographic recurrence of a posterior communicating artery aneurysm that was previously ruptured and clipped 20 years earlier. B, microcatheter angiographic injection nicely demonstrates the aneurysm neck, which is narrowed by the clip and amenable to endovascular coiling. C, the aneurysm is shown after coiling.
is relatively safe and in some instances safer than ignoring aneurysm remnants. In addition, it is very important to understand the angioarchitecture of the remnant. Improved visualization can often be
obtained with strategic 2-dimensional angiographic views, 3-dimensional angiography, and in selected cases, microcatheter injections just proximal to or lightly within the aneurysm. Figure 5 depicts a previously clipped aneurysm that was shown to have
FIGURE 6. A previously coiled ophthalmic artery aneurysm is seen with a recurrence after a second endovascular treatment. Note that the length of the recurrence is roughly twice the width of the neck.
FIGURE 7. The aneurysm in Figure 6 is shown through the operative microscope. This remnant was treated with microsurgical clipping. Note the excellent visualization of the neck with the original coils in place.
CLINICAL NEUROSURGERY
VOLUME 62 | NUMBER 1 | AUGUST 2015 | 105
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BINNING AND VEZNEDAROGLU
FIGURE 9. Basic algorithm for aneurysm remnant monitoring with serial imaging.
FIGURE 8. Basic algorithm for aneurysm remnant treatment.
recurrence on angiography, but the neck could not be defined until microcatheter injections were performed. New endovascular devices may be considered when deciding how to treat and aneurysm remnant. For example, recurrences of large or giant internal carotid artery aneurysms may be amenable to some of the flow diversion devices on the market. In certain instances, surgical clipping of aneurysm remnants from previously coiled aneurysms will be necessary. Just as in endovascular treatments, it is imperative to understand the angiogram and the anatomy of the recurrence. As a general guideline for clipping, the length of the remnant should be twice the length of the neck to allow enough room for clip application without compromising the parent vessel.4 In addition, it is inadvisable to remove coils that were previously placed. If the neck is adequate for clipping, coil removal does not aid in visualization or exposure for most aneurysms and can lead to disintegration of the aneurysm wall (Figures 6-7).4 The most important factors to consider for aneurysm remnants, of course, are the best course of action for the patient and the intervention that will produce the best clinical outcome. Comprehensive open and endovascular neurosurgeons have all of the tools for aneurysm treatment in our armamentarium. It is important that we truly understand how to use those tools and to exercise the best decision making that is based on patientspecific factors (Figures 8-9).
106 | VOLUME 62 | NUMBER 1 | AUGUST 2015
CONCLUSION The decision of whether to treat or observe aneurysm remnants requires a comprehensive and individualized approach. It is important to treat the patient holistically, not just the “film.” In this modern era of aneurysm treatment, both open and endovascular options must be evaluated with the patient by either a multidisciplinary team or a comprehensive neurosurgeon skilled in both. This approach ensures that the decision is based on the modality that will achieve the best outcome for the patient and reduces physician bias. Disclosures Dr Veznedaroglu is a consultant for CORDIS, Codman, Microvention, and Stryker. Dr Binning has no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article.
REFERENCES 1. Roy D, Milot G, Raymond J. Endovascular treatment of unruptured aneurysms. Stroke. 2001;32(9):1998-2004. 2. Ortiz R, Stefanski M, Rosenwasser R, Veznedaroglu E. Cigarette smoking as a risk factor for recurrence of aneurysms treated by endosaccular occlusion. J Neurosurg. 2008;108(4):672-675. 3. Ringer AJ, Rodriguez-Mercado R, Veznedaroglu E, et al. Defining the risk of retreatment for aneurysm recurrence or residual after initial treatment by endovascular coiling: a multicenter study. Neurosurgery. 2009;65(2):311-315. 4. Veznedaroglu E, Benitez RP, Rosenwasser RH. Surgically treated aneurysms previously coiled: lessons learned. Neurosurgery. 2008;62(6 suppl 3): 1516-1524.
www.neurosurgery-online.com
Copyright © Congress of Neurological Surgeons. Unauthorized reproduction of this article is prohibited
Aneurysm Remnants After Coiling and Clipping: Considerations in Surgical and Endovascular Treatment Options Mandy J. Binning, MD Erol Veznedaroglu, MD Capital Institute of Neurosciences, Capital Health Systems, Trenton and Pennington, New Jersey Correspondence: Erol Veznedaroglu, MD, Two Capital Way, Ste 456, Pennington, NJ 08534. E-mail: [email protected]
Copyright © 2015 by the Congress of Neurological Surgeons.
T
he clinical significance of remnants or recurrences of treated intracranial aneurysms is not a new concern for vascular neurosurgeons. However, in the endovascular era of aneurysm treatment, there has been more focus on this problem. It should be noted, first and foremost, that not all aneurysm remnants are created equally. Although the Raymond and Roy classification system1 is widely used as a simple method to describe aneurysm remnants, the system does not have widespread clinical utility. For example, it does not indicate which patients require retreatment and which should be followed up with serial imaging. Diagrammatic classification systems fail to account for important clinical details such as rupture status, sidewall recurrences, follow-up stability, and patient comorbidities (Table). In the modern era of aneurysm treatment, remnants must be addressed in a comprehensive way on a case-bycase basis to ensure the best patient outcomes.
BACKGROUND
The 2014 CNS Annual Meeting presentation on which this article is based is available at http://bit.ly/1EO5oXR.
CLINICAL NEUROSURGERY
Although widely used, the Raymond and Roy aneurysm recurrence classification is purely illustrative (not prognostic) when it comes to which aneurysm remnants are of clinical significance or should be retreated. The classification was originally created to describe angiographic follow-up for unruptured aneurysms that were treated endovascularly. Class 1 was described as no residual aneurysm; Class 2 had angiographic filling at the neck; and Class 3 involved residual aneurysm filling anywhere beyond the neck. Although this classification is simple, it is too simple to use as any sort of guideline for treating patients. What the classification does not and was never meant to take into account are patient factors that determine whether aneurysm remnants should be treated or observed. For example, the original article by Roy et al1 described only follow-up in unruptured aneurysms. Aneurysm filling beyond the neck in a ruptured aneurysm intuitively carries a much different risk
compared with filling of an electively treated unruptured aneurysm. In addition, the degree and location of filling or recurrence within the treated aneurysm are important factors when reviewing the angiographic remnant. Sidewall filling between the coil mass and wall of the aneurysm is a more ominous sign than a 10% recurrence centrally just above the neck (Figure 1). Sidewall filling can signal an endovascular leak of sorts that can lead to a high rate of rerupture by allowing filling to reach the dome (Figure 2A-2C). In our practice, sidewall recurrences are treated expeditiously. Length of follow-up and stability of the remnant on angiographic or noninvasive imaging are also factored into whether an aneurysm remnant requires treatment. For example, an aneurysm remnant that has remained unchanged on magnetic resonance angiography and 5-year follow-up angiography is unlikely to change and rarely requires intervention (Figure 3). Finally, patients who smoke have a higher risk for aneurysm recurrence and should be observed more closely and for a longer period of time or should be treated early, depending on the other factors mentioned above.2
TREATMENT The first choice to make when addressing an aneurysm remnant is whether the aneurysm
TABLE. Angiographic and Patient Factors That Increase Risk of Aneurysm Rerupture Previously ruptured aneurysm A remnant that enlarges over time on serial imaging (magnetic resonance angiography/ angiography) A remnant that fills between the coil mass and the wall of the aneurysm toward the dome (sidewall filling) Patient is a smoker
VOLUME 62 | NUMBER 1 | AUGUST 2015 | 103
Copyright © Congress of Neurological Surgeons. Unauthorized reproduction of this article is prohibited
BINNING AND VEZNEDAROGLU
FIGURE 3. A remnant from a previously ruptured but coiled superior cerebellar artery aneurysm has remained stable over 5 years and will continue to be observed.
FIGURE 1. A basilar bifurcation aneurysm was previously coiled and, on followup angiography, shows a sidewall recurrence between the coil mass and the dome.
When remnants need to be retreated, it is important to recognize that endovascular aneurysm retreatment carries a low complication rate.3 A series of 311 patients who underwent 352 retreatment procedures revealed a total risk of death or major disability of 1.13% per procedure or 1.28% per patient. Although the goal is always to provide the best possible treatment the first time, that study showed that retreatment
needs to be retreated. Although endovascular recurrences are more common, remnants can be seen in both clipped and coiled aneurysms. As discussed, a remnant located at or just above the neck carries a low risk of long-term change. It is common to follow up these remnants radiographically (Figures 3-4).
FIGURE 2. A, sidewall filling of this coiled aneurysm from Figure 1. B and C, filling of the dome of the aneurysm in Figure 1. Sidewall filling acted as an endovascular leak between the aneurysm wall and the coil mass.
104 | VOLUME 62 | NUMBER 1 | AUGUST 2015
FIGURE 4. A remnant from a previously clipped, unruptured posterior inferior cerebellar artery aneurysm has remained stable over 5 years and will continue to be observed.
www.neurosurgery-online.com
Copyright © Congress of Neurological Surgeons. Unauthorized reproduction of this article is prohibited
ANEURYSM REMNANTS
FIGURE 5. A, angiographic recurrence of a posterior communicating artery aneurysm that was previously ruptured and clipped 20 years earlier. B, microcatheter angiographic injection nicely demonstrates the aneurysm neck, which is narrowed by the clip and amenable to endovascular coiling. C, the aneurysm is shown after coiling.
is relatively safe and in some instances safer than ignoring aneurysm remnants. In addition, it is very important to understand the angioarchitecture of the remnant. Improved visualization can often be
obtained with strategic 2-dimensional angiographic views, 3-dimensional angiography, and in selected cases, microcatheter injections just proximal to or lightly within the aneurysm. Figure 5 depicts a previously clipped aneurysm that was shown to have
FIGURE 6. A previously coiled ophthalmic artery aneurysm is seen with a recurrence after a second endovascular treatment. Note that the length of the recurrence is roughly twice the width of the neck.
FIGURE 7. The aneurysm in Figure 6 is shown through the operative microscope. This remnant was treated with microsurgical clipping. Note the excellent visualization of the neck with the original coils in place.
CLINICAL NEUROSURGERY
VOLUME 62 | NUMBER 1 | AUGUST 2015 | 105
Copyright © Congress of Neurological Surgeons. Unauthorized reproduction of this article is prohibited
BINNING AND VEZNEDAROGLU
FIGURE 9. Basic algorithm for aneurysm remnant monitoring with serial imaging.
FIGURE 8. Basic algorithm for aneurysm remnant treatment.
recurrence on angiography, but the neck could not be defined until microcatheter injections were performed. New endovascular devices may be considered when deciding how to treat and aneurysm remnant. For example, recurrences of large or giant internal carotid artery aneurysms may be amenable to some of the flow diversion devices on the market. In certain instances, surgical clipping of aneurysm remnants from previously coiled aneurysms will be necessary. Just as in endovascular treatments, it is imperative to understand the angiogram and the anatomy of the recurrence. As a general guideline for clipping, the length of the remnant should be twice the length of the neck to allow enough room for clip application without compromising the parent vessel.4 In addition, it is inadvisable to remove coils that were previously placed. If the neck is adequate for clipping, coil removal does not aid in visualization or exposure for most aneurysms and can lead to disintegration of the aneurysm wall (Figures 6-7).4 The most important factors to consider for aneurysm remnants, of course, are the best course of action for the patient and the intervention that will produce the best clinical outcome. Comprehensive open and endovascular neurosurgeons have all of the tools for aneurysm treatment in our armamentarium. It is important that we truly understand how to use those tools and to exercise the best decision making that is based on patientspecific factors (Figures 8-9).
106 | VOLUME 62 | NUMBER 1 | AUGUST 2015
CONCLUSION The decision of whether to treat or observe aneurysm remnants requires a comprehensive and individualized approach. It is important to treat the patient holistically, not just the “film.” In this modern era of aneurysm treatment, both open and endovascular options must be evaluated with the patient by either a multidisciplinary team or a comprehensive neurosurgeon skilled in both. This approach ensures that the decision is based on the modality that will achieve the best outcome for the patient and reduces physician bias. Disclosures Dr Veznedaroglu is a consultant for CORDIS, Codman, Microvention, and Stryker. Dr Binning has no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article.
REFERENCES 1. Roy D, Milot G, Raymond J. Endovascular treatment of unruptured aneurysms. Stroke. 2001;32(9):1998-2004. 2. Ortiz R, Stefanski M, Rosenwasser R, Veznedaroglu E. Cigarette smoking as a risk factor for recurrence of aneurysms treated by endosaccular occlusion. J Neurosurg. 2008;108(4):672-675. 3. Ringer AJ, Rodriguez-Mercado R, Veznedaroglu E, et al. Defining the risk of retreatment for aneurysm recurrence or residual after initial treatment by endovascular coiling: a multicenter study. Neurosurgery. 2009;65(2):311-315. 4. Veznedaroglu E, Benitez RP, Rosenwasser RH. Surgically treated aneurysms previously coiled: lessons learned. Neurosurgery. 2008;62(6 suppl 3): 1516-1524.
www.neurosurgery-online.com
Copyright © Congress of Neurological Surgeons. Unauthorized reproduction of this article is prohibited
