Perspectives Commentary on: Correlation Between the Aneurysm Morphometry and Severity of Subarachnoid Hemorrhage in the Posterior Cerebral Circulation by Tykocki and Kostkiewicz World Neurosurg 82:1100-1105, 2014
Should I Treat or Should I Not? Behnam Rezai Jahromi, Mika Niemela¨, Juha Hernesniemi
CONFLICT OF TREATMENT OPTIONS
U
nruptured intracranial aneurysms and their treatment methods have been under discussion since endovascular coiling started more than 20 years ago (6). The question is simple: When should an intracranial aneurysm be treated and when not? Which is the better treatment option, clipping or coiling? The answers to these questions are more complex, and one might easily find him or herself in the middle of the battle of randomized controlled trials (8). For many years, it seemed that size of an aneurysm was the only factor affecting rupture rate. However, hypertension, smoking, female sex, and immediate family member with aneurysmal subarachnoid hemorrhage increase risk of aneurysm rupture (13).
HELSINKI DATA The Helsinki aneurysm database comprises more than 10,900 patients with more than 13,500 aneurysms. One beneficial factor in a Nordic health care system is that each person has health care insurance covered by government. Also, there are, for example, in the whole Finland only 5 neurosurgical centers responsible from defined catchment area. Thus, our epidemiologic studies are more representative because there is less selection bias in our studies with a long follow-up time. The anatomical and morphologic study of Elsharkawy et al. (3) shows that in middle cerebral artery aneurysms, the location at the main bifurcation, wall irregularity, and less spherical geometry are independently associated with rupture of middle cerebral artery aneurysms with correlation to aneurysm size. The distal anterior cerebral artery aneurysm (DACA) study showed greater presentation of hematomas than ruptured aneurysms in general (53% vs. 26%). Mostly hematomas occurred in frontal lobe and thus were better tolerated. Ruptured and unruptured DACAs
Key words Anatomy - Cerebral aneurysm - Computed tomography angiography - Hemodynamics - Morphology -
1034
Abbreviations and Acronyms DACA: Distal anterior cerebral artery aneurysm PCA: Posterior cerebral artery
www.SCIENCEDIRECT.com
have their own specific characteristics. When ruptured, DACAs also are smaller than average aneurysms: their mean size varied from 5 to 8 mm (9). Ruptured posterior cerebral artery (PCA) aneurysms usually are smaller than 10 mm and are located distally in the artery. At each PCA segment, saccular PCA aneurysms have a typical dome orientation (5). In study of Lehto et al. (10) on posterior inferior cerebellar artery aneurysms, most aneurysms occur either on the dominant vertebral artery or on a vessel with the same diameter as its contralateral counterpart. A multicenter international study of surgical clipping of unruptured very small intracranial aneurysms, which is still in progress, showed that even mini-aneurysms can be clipped (2). Naturally, the neurosurgeon should justify surgery to patient and oneself. Because cerebrovascular lesions are still among the most demanding lesions in neurosurgery, it is justified to centralize their treatment in large centers with greatest experience. Experience is one crucial factor, but one should not forget the need for outstanding neuroanesthesia, nurses, and other department staff. With these factors, neurosurgeon is able to provide the best treatment for patients.
BALANCING The best treatment is prophylaxis. Risks of treatment should be weighed against the natural history of the disease together with patients’ wishes. But how to identify rupture-prone aneurysms? Is it aneurysm wall structure, projection, location or combination of all? And when decision of treatment has been done, how the aneurysm should be treated? It is far safer for the patient to quit smoking than to go through invasive treatment. How to find reliable predictors for daily clinical practice? Tykocki and Kostkiewicz found a “correlation between the aneurysm morphometry and severity of subarachnoid
Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland To whom correspondence should be addressed: Juha Hernesniemi, M.D., Ph.D. [E-mail: [email protected]] Citation: World Neurosurg. (2015) 83, 6:1034-1035. http://dx.doi.org/10.1016/j.wneu.2015.01.050
WORLD NEUROSURGERY, http://dx.doi.org/10.1016/j.wneu.2015.01.050
PERSPECTIVES
hemorrhage in the posterior cerebral circulation.” Inflow angle and aneurysm size ratio were found to be correlated with grading in Fisher revised scale, and the World Federation of Neurosurgical Societies scale was correlated with inflow angle. Perhaps the authors can design a prospective study in which they analyze conservatively treated aneurysms based on the anatomical and morphologic factor and see how these affect patient outcome. In the future, individual hemodynamic models can guide us to the ideal treatment options and their timing. We hope that further investigations and multidisciplinary approach to these lesions could provide us clinical guidelines. With these
REFERENCES 1. Bilguvar K, Yasuno K, Niemelä M, Ruigrok YM, und zu Fraunberg von M, van Duijn CM, van den Berg LH, Mane S, Mason CE, Choi M, Gaál E, Bayri Y, Kolb L, Arlier Z, Ravuri S, Ronkainen A, Tajima A, Laakso A, Hata A, Kasuya H, Koivisto T, Rinne J, Ohman J, Breteler MM, Wijmenga C, State MW, Rinkel GJ, Hernesniemi J, Jääskeläinen JE, Palotie A, Inoue I, Lifton RP, Günel M: Susceptibility loci for intracranial aneurysm in European and Japanese populations. Nat Genet 40:1472-1477, 2008. 2. Bruneau M, Amin-Hanjani S, Koroknay-Pál P, Bijlenga P, Jahromi BR, Lehto H, Kivisaari R, Schaller K, Charbel FT, Kahn S, Melot C, Niemela MR, Hernesniemi JA: 129 A multicenter international study of surgical clipping for unruptured very small intracranial aneurysms. Neurosurgery 61(Suppl 1):201-202, 2014. 3. Elsharkawy A, Lehecka M, Niemelä M, Kivelev J, Billon-Grand R, Lehto H, Kivisaari R, Hernesniemi J: Anatomic risk factors for middle cerebral artery aneurysm rupture. Neurosurgery 73:825-837; discussion 836-837 2013. 4. Frösen J, Piippo A, Paetau A, Kangasniemi M, Niemelä M, Hernesniemi J, Jääskeläinen J: Remodeling of saccular cerebral artery aneurysm wall is associated with rupture histological analysis of 24 unruptured and 42 ruptured cases. Stroke 35:2287-2293, 2004. 5. Goehre F, Jahromi BR, Hernesniemi J, Elsharkawy A, Kivisaari R, und zu Fraunberg von M, Jääskeläinen J, Lehto H, Lehecka M: Characteristics of posterior cerebral artery aneurysms. Neurosurgery 75:134-144, 2014. 6. Guglielmi G, Viñuela F, Duckwiler G, Dion J, Lylyk P, Berenstein A, Strother C, Graves V, Halbach V, Nicholas D, Hopkins N, Ferguson R, Sepetka I: Endovascular treatment of posterior
medical guidelines, clinicians can standardize medical care more effectively. When ruptured, an aneurysm’s morphometry and location have great impact on patient outcome. Inflammation, hemodynamics, genetics, aneurysm wall structure, and many other factors are related to aneurysm formation (1, 4, 11, 12, 14). When etiologies of aneurysm formations are understood, we can provide the ultimate treatment for patients suffering from these lesions (7). With new imaging systems we are able to treat patients more selectively and accurately, by means of endovascular treatment and open microsurgery. Because we all are lifelong students of anatomy, Tykocki and Kostkiewicz’s study should be noted.
circulation aneurysms by electrothrombosis using electrically detachable coils. J Neurosurg 77: 515-524, 1992. 7. Huttunen T, und zu Fraunberg von M, F rösen J, Lehecka M, Tromp G, Helin K, Koivisto T, Rinne J, Ronkainen A, Hernesniemi J, Jääskeläinen JE: Saccular intracranial aneurysm disease: distribution of site, size, and age suggests different etiologies for aneurysm formation and rupture in 316 familial and 1454 sporadic eastern Finnish patients. Neurosurgery 66: 631-638, 2010. 8. Korja M, Hernesniemi J, Lawton MT, Spetzler RF, Morgan MK: Is cerebrovascular neurosurgery sacrificed on the altar of RCTs? Lancet 384:27-28, 2014. 9. Lehecka M, Dashti R, Lehto H, Kivisaari R, Niemelä M, Hernesniemi J: Distal anterior cerebral artery aneurysms. Acta Neurochir Suppl 107: 15-26, 2010. 10. Lehto H, Kivisaari R, Niemelä M, Dashti R, Elsharkawy A, Harati A, Satopää J, KoroknayPál P, Laakso A, Hernesniemi J: Seventy aneurysms of the posterior inferior cerebellar artery: anatomical features and value of computed tomography angiography in microneurosurgery. World Neurosurg 82:1106-1112, 2014. 11. Marbacher S, Marjamaa J, Bradacova K, Gunten von M, Honkanen P, Abo-Ramadan U, Hernesniemi J, Niemelä M, Frösen J: Loss of mural cells leads to wall degeneration, aneurysm growth, and eventual rupture in a rat aneurysm model. Stroke 45:248-254, 2014. 12. Tulamo R, Frösen J, Junnikkala S, Paetau A, Pitkäniemi J, Kangasniemi M, Niemelä M, Jääskeläinen J, Jokitalo E, Karatas A, Hernesniemi J, Meri S: Complement activation associates with saccular cerebral artery aneurysm
WORLD NEUROSURGERY 83 [6]: 1034-1035, JUNE 2015
wall degeneration and rupture. Neurosurgery 59: 1069-1076; discussion 1076-1077 2006. 13. Wiebers DO, Whisnant JP, Huston J, Meissner I, Brown RD, Piepgras DG, Forbes GS, Thielen K, Nichols D, O’Fallon WM, Peacock J, Jaeger L, Kassell NF, Kongable-Beckman GL, Torner JC; International Study of Unruptured Intracranial Aneurysms Investigators: Unruptured intracranial aneurysms: natural history, clinical outcome, and risks of surgical and endovascular treatment. Lancet 362:103-110, 2003. 14. Yasuno K, Bilguvar K, Bijlenga P, Low S-K, Krischek B, Auburger G, Simon M, Krex D, Arlier Z, Nayak N, Ruigrok YM, Niemelä M, Tajima A, von und zu Fraunberg M, Dóczi T, Wirjatijasa F, Hata A, Blasco J, Oszvald A, Kasuya H, Zilani G, Schoch B, Singh P, Stüer C, Risselada R, Beck J, Sola T, Ricciardi F, Aromaa A, Illig T, Schreiber S, van Duijn CM, van den Berg LH, Perret C, Proust C, Roder C, Ozturk AK, Gaál E, Berg D, Geisen C, Friedrich CM, Summers P, Frangi AF, State MW, Wichmann HE, Breteler MM, Wijmenga C, Mane S, Peltonen L, Elio V, Sturkenboom MC, Lawford P, Byrne J, Macho J, Sandalcioglu EI, Meyer B, Raabe A, Steinmetz H, Rüfenacht D, Jääskeläinen JE, Hernesniemi J, Rinkel GJ, Zembutsu H, Inoue I, Palotie A, Cambien F, Nakamura Y, Lifton RP, Günel M: Genome-wide association study of intracranial aneurysm identifies three new risk loci. Nat Genet 42:420-425, 2010.
Citation: World Neurosurg. (2015) 83, 6:1034-1035. http://dx.doi.org/10.1016/j.wneu.2015.01.050 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2015 Elsevier Inc. All rights reserved.
www.WORLDNEUROSURGERY.org
1035
Should I Treat or Should I Not? Behnam Rezai Jahromi, Mika Niemela¨, Juha Hernesniemi
CONFLICT OF TREATMENT OPTIONS
U
nruptured intracranial aneurysms and their treatment methods have been under discussion since endovascular coiling started more than 20 years ago (6). The question is simple: When should an intracranial aneurysm be treated and when not? Which is the better treatment option, clipping or coiling? The answers to these questions are more complex, and one might easily find him or herself in the middle of the battle of randomized controlled trials (8). For many years, it seemed that size of an aneurysm was the only factor affecting rupture rate. However, hypertension, smoking, female sex, and immediate family member with aneurysmal subarachnoid hemorrhage increase risk of aneurysm rupture (13).
HELSINKI DATA The Helsinki aneurysm database comprises more than 10,900 patients with more than 13,500 aneurysms. One beneficial factor in a Nordic health care system is that each person has health care insurance covered by government. Also, there are, for example, in the whole Finland only 5 neurosurgical centers responsible from defined catchment area. Thus, our epidemiologic studies are more representative because there is less selection bias in our studies with a long follow-up time. The anatomical and morphologic study of Elsharkawy et al. (3) shows that in middle cerebral artery aneurysms, the location at the main bifurcation, wall irregularity, and less spherical geometry are independently associated with rupture of middle cerebral artery aneurysms with correlation to aneurysm size. The distal anterior cerebral artery aneurysm (DACA) study showed greater presentation of hematomas than ruptured aneurysms in general (53% vs. 26%). Mostly hematomas occurred in frontal lobe and thus were better tolerated. Ruptured and unruptured DACAs
Key words Anatomy - Cerebral aneurysm - Computed tomography angiography - Hemodynamics - Morphology -
1034
Abbreviations and Acronyms DACA: Distal anterior cerebral artery aneurysm PCA: Posterior cerebral artery
www.SCIENCEDIRECT.com
have their own specific characteristics. When ruptured, DACAs also are smaller than average aneurysms: their mean size varied from 5 to 8 mm (9). Ruptured posterior cerebral artery (PCA) aneurysms usually are smaller than 10 mm and are located distally in the artery. At each PCA segment, saccular PCA aneurysms have a typical dome orientation (5). In study of Lehto et al. (10) on posterior inferior cerebellar artery aneurysms, most aneurysms occur either on the dominant vertebral artery or on a vessel with the same diameter as its contralateral counterpart. A multicenter international study of surgical clipping of unruptured very small intracranial aneurysms, which is still in progress, showed that even mini-aneurysms can be clipped (2). Naturally, the neurosurgeon should justify surgery to patient and oneself. Because cerebrovascular lesions are still among the most demanding lesions in neurosurgery, it is justified to centralize their treatment in large centers with greatest experience. Experience is one crucial factor, but one should not forget the need for outstanding neuroanesthesia, nurses, and other department staff. With these factors, neurosurgeon is able to provide the best treatment for patients.
BALANCING The best treatment is prophylaxis. Risks of treatment should be weighed against the natural history of the disease together with patients’ wishes. But how to identify rupture-prone aneurysms? Is it aneurysm wall structure, projection, location or combination of all? And when decision of treatment has been done, how the aneurysm should be treated? It is far safer for the patient to quit smoking than to go through invasive treatment. How to find reliable predictors for daily clinical practice? Tykocki and Kostkiewicz found a “correlation between the aneurysm morphometry and severity of subarachnoid
Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland To whom correspondence should be addressed: Juha Hernesniemi, M.D., Ph.D. [E-mail: [email protected]] Citation: World Neurosurg. (2015) 83, 6:1034-1035. http://dx.doi.org/10.1016/j.wneu.2015.01.050
WORLD NEUROSURGERY, http://dx.doi.org/10.1016/j.wneu.2015.01.050
PERSPECTIVES
hemorrhage in the posterior cerebral circulation.” Inflow angle and aneurysm size ratio were found to be correlated with grading in Fisher revised scale, and the World Federation of Neurosurgical Societies scale was correlated with inflow angle. Perhaps the authors can design a prospective study in which they analyze conservatively treated aneurysms based on the anatomical and morphologic factor and see how these affect patient outcome. In the future, individual hemodynamic models can guide us to the ideal treatment options and their timing. We hope that further investigations and multidisciplinary approach to these lesions could provide us clinical guidelines. With these
REFERENCES 1. Bilguvar K, Yasuno K, Niemelä M, Ruigrok YM, und zu Fraunberg von M, van Duijn CM, van den Berg LH, Mane S, Mason CE, Choi M, Gaál E, Bayri Y, Kolb L, Arlier Z, Ravuri S, Ronkainen A, Tajima A, Laakso A, Hata A, Kasuya H, Koivisto T, Rinne J, Ohman J, Breteler MM, Wijmenga C, State MW, Rinkel GJ, Hernesniemi J, Jääskeläinen JE, Palotie A, Inoue I, Lifton RP, Günel M: Susceptibility loci for intracranial aneurysm in European and Japanese populations. Nat Genet 40:1472-1477, 2008. 2. Bruneau M, Amin-Hanjani S, Koroknay-Pál P, Bijlenga P, Jahromi BR, Lehto H, Kivisaari R, Schaller K, Charbel FT, Kahn S, Melot C, Niemela MR, Hernesniemi JA: 129 A multicenter international study of surgical clipping for unruptured very small intracranial aneurysms. Neurosurgery 61(Suppl 1):201-202, 2014. 3. Elsharkawy A, Lehecka M, Niemelä M, Kivelev J, Billon-Grand R, Lehto H, Kivisaari R, Hernesniemi J: Anatomic risk factors for middle cerebral artery aneurysm rupture. Neurosurgery 73:825-837; discussion 836-837 2013. 4. Frösen J, Piippo A, Paetau A, Kangasniemi M, Niemelä M, Hernesniemi J, Jääskeläinen J: Remodeling of saccular cerebral artery aneurysm wall is associated with rupture histological analysis of 24 unruptured and 42 ruptured cases. Stroke 35:2287-2293, 2004. 5. Goehre F, Jahromi BR, Hernesniemi J, Elsharkawy A, Kivisaari R, und zu Fraunberg von M, Jääskeläinen J, Lehto H, Lehecka M: Characteristics of posterior cerebral artery aneurysms. Neurosurgery 75:134-144, 2014. 6. Guglielmi G, Viñuela F, Duckwiler G, Dion J, Lylyk P, Berenstein A, Strother C, Graves V, Halbach V, Nicholas D, Hopkins N, Ferguson R, Sepetka I: Endovascular treatment of posterior
medical guidelines, clinicians can standardize medical care more effectively. When ruptured, an aneurysm’s morphometry and location have great impact on patient outcome. Inflammation, hemodynamics, genetics, aneurysm wall structure, and many other factors are related to aneurysm formation (1, 4, 11, 12, 14). When etiologies of aneurysm formations are understood, we can provide the ultimate treatment for patients suffering from these lesions (7). With new imaging systems we are able to treat patients more selectively and accurately, by means of endovascular treatment and open microsurgery. Because we all are lifelong students of anatomy, Tykocki and Kostkiewicz’s study should be noted.
circulation aneurysms by electrothrombosis using electrically detachable coils. J Neurosurg 77: 515-524, 1992. 7. Huttunen T, und zu Fraunberg von M, F rösen J, Lehecka M, Tromp G, Helin K, Koivisto T, Rinne J, Ronkainen A, Hernesniemi J, Jääskeläinen JE: Saccular intracranial aneurysm disease: distribution of site, size, and age suggests different etiologies for aneurysm formation and rupture in 316 familial and 1454 sporadic eastern Finnish patients. Neurosurgery 66: 631-638, 2010. 8. Korja M, Hernesniemi J, Lawton MT, Spetzler RF, Morgan MK: Is cerebrovascular neurosurgery sacrificed on the altar of RCTs? Lancet 384:27-28, 2014. 9. Lehecka M, Dashti R, Lehto H, Kivisaari R, Niemelä M, Hernesniemi J: Distal anterior cerebral artery aneurysms. Acta Neurochir Suppl 107: 15-26, 2010. 10. Lehto H, Kivisaari R, Niemelä M, Dashti R, Elsharkawy A, Harati A, Satopää J, KoroknayPál P, Laakso A, Hernesniemi J: Seventy aneurysms of the posterior inferior cerebellar artery: anatomical features and value of computed tomography angiography in microneurosurgery. World Neurosurg 82:1106-1112, 2014. 11. Marbacher S, Marjamaa J, Bradacova K, Gunten von M, Honkanen P, Abo-Ramadan U, Hernesniemi J, Niemelä M, Frösen J: Loss of mural cells leads to wall degeneration, aneurysm growth, and eventual rupture in a rat aneurysm model. Stroke 45:248-254, 2014. 12. Tulamo R, Frösen J, Junnikkala S, Paetau A, Pitkäniemi J, Kangasniemi M, Niemelä M, Jääskeläinen J, Jokitalo E, Karatas A, Hernesniemi J, Meri S: Complement activation associates with saccular cerebral artery aneurysm
WORLD NEUROSURGERY 83 [6]: 1034-1035, JUNE 2015
wall degeneration and rupture. Neurosurgery 59: 1069-1076; discussion 1076-1077 2006. 13. Wiebers DO, Whisnant JP, Huston J, Meissner I, Brown RD, Piepgras DG, Forbes GS, Thielen K, Nichols D, O’Fallon WM, Peacock J, Jaeger L, Kassell NF, Kongable-Beckman GL, Torner JC; International Study of Unruptured Intracranial Aneurysms Investigators: Unruptured intracranial aneurysms: natural history, clinical outcome, and risks of surgical and endovascular treatment. Lancet 362:103-110, 2003. 14. Yasuno K, Bilguvar K, Bijlenga P, Low S-K, Krischek B, Auburger G, Simon M, Krex D, Arlier Z, Nayak N, Ruigrok YM, Niemelä M, Tajima A, von und zu Fraunberg M, Dóczi T, Wirjatijasa F, Hata A, Blasco J, Oszvald A, Kasuya H, Zilani G, Schoch B, Singh P, Stüer C, Risselada R, Beck J, Sola T, Ricciardi F, Aromaa A, Illig T, Schreiber S, van Duijn CM, van den Berg LH, Perret C, Proust C, Roder C, Ozturk AK, Gaál E, Berg D, Geisen C, Friedrich CM, Summers P, Frangi AF, State MW, Wichmann HE, Breteler MM, Wijmenga C, Mane S, Peltonen L, Elio V, Sturkenboom MC, Lawford P, Byrne J, Macho J, Sandalcioglu EI, Meyer B, Raabe A, Steinmetz H, Rüfenacht D, Jääskeläinen JE, Hernesniemi J, Rinkel GJ, Zembutsu H, Inoue I, Palotie A, Cambien F, Nakamura Y, Lifton RP, Günel M: Genome-wide association study of intracranial aneurysm identifies three new risk loci. Nat Genet 42:420-425, 2010.
Citation: World Neurosurg. (2015) 83, 6:1034-1035. http://dx.doi.org/10.1016/j.wneu.2015.01.050 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2015 Elsevier Inc. All rights reserved.
www.WORLDNEUROSURGERY.org
1035
