Simulation of the natural history of cerebral aneurysms based on data from the International Study of Unruptured Intracranial Aneurysms

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  • 1 Department of Neurological Surgery, Aichi Medical University, Aichi, Japan
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Object

Despite recent publications of large-scale study data, controversy over the management of unruptured cerebral aneurysms continues. The low rupture rates in the International Study of Unruptured Intracranial Aneurysms (ISUIA) apparently contradicted surgeons’ experiences with ruptured aneurysms. In the present study, based on data from the ISUIA, a mathematical model describing the natural history of cerebral aneurysms was developed. With this model, the author aimed to examine the validity of data from the ISUIA and to provide a better treatment guideline for unruptured aneurysms.

Methods

The author made a computer simulation of the natural history of cerebral aneurysms that was used to calculate such figures as the prevalence of unruptured aneurysms, incidence of subarachnoid hemorrhage (SAH), and age and size distribution of both unruptured and ruptured aneurysms. The lifetime lesion rupture probability for individual patients with various ages and aneurysm sizes was also computed, thereby providing a useful index to help patients in the medical decision-making process.

The computer model produced a sample of unruptured aneurysms in the general population with a prevalence of 4.2% and a median diameter of 5.8 mm. These unruptured aneurysms—affected by the rupture rate reported in the ISUIA—had a yearly SAH incidence of 19.6 per 100,000 persons. The median diameter of these aneurysms was 9.4 mm.

Conclusions

Findings in the present study validated the results of the ISUIA by showing that the seemingly low rupture rates could explain the statistical data for ruptured aneurysms. With the featured model, the author calculated the lifetime probability of lesion rupture—a useful measure for deciding on the optimal treatment for unruptured aneurysms.

Abbreviations used in this paper:ISUIA = International Study of Unruptured Intracranial Aneurysms; SAH = subarachnoid hemorrhage; SD = standard deviation.

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Contributor Notes

Address reprint requests to: Han Soo Chang, M.D., Department of Neurological Surgery, Aichi Medical University, Yazako-Karimata, Nagakute-cho, Aichi-gun, Aichi 480-1195, Japan. email: chang@aichi-med-u.ac.jp.
  • 1

    Anonymous: Unruptured intracranial aneurysms—risk of rupture and risks of surgical intervention. International Study of Unruptured Intracranial Aneurysms Investigators. N Engl J Med 339:17251733, 1998

    • Search Google Scholar
    • Export Citation
  • 2

    Ausman JI: Why the International Study of Unruptured Intracranial Aneurysms had lost credibility with neuroscientists. Surg Neurol 58:287290, 2002

    • Search Google Scholar
    • Export Citation
  • 3

    Ausman JI, & Roitberg B: A response from the ISUIA. International Study on Unruptured Intracranial. Aneurysms Surg Neurol 52:428430, 1999

    • Search Google Scholar
    • Export Citation
  • 4

    Bederson JB, , Awad IA, , Wiebers DO, , Piepgras D, , Haley EC Jr, & Brott T, : Recommendations for the management of patients with unruptured intracranial aneurysms: a statement for healthcare professionals from the Stroke Council of the American Heart Association. Circulation 102:23002308, 2000

    • Search Google Scholar
    • Export Citation
  • 5

    Bland M: Mortality statistics and population structure. An Introduction to Medical Statistics. Oxford, Oxford University Press, 1995. 291305

    • Search Google Scholar
    • Export Citation
  • 6

    Chang HS, , Hongo K, , Nakagawa H, & Tsuge T: Surgical decision-making on cerebral cavernous malformations. J Clin Neurosci 8:416420, 2001

  • 7

    Chang HS, & Kirino T: Quantification of operative benefit for unruptured cerebral aneurysms: a theoretical approach. J Neurosurg 83:413420, 1995

    • Search Google Scholar
    • Export Citation
  • 8

    Chang HS, & Nihei H: Theoretical comparison of surgery and radiosurgery in cerebral arteriovenous malformations. J Neurosurg 90:709719, 1999

    • Search Google Scholar
    • Export Citation
  • 9

    Dickey P, & Kailasnath P: The diameter-cube hypothesis: a new biophysical model of aneurysm rupture. Surg Neurol 58:166180, 2002

  • 10

    Imaizumi S, , Onuma T, , Motohashi O, & Kameyama M: Growth of small unruptured intracranial aneurysm: case report. Surg Neurol 58:155157, 2002

    • Search Google Scholar
    • Export Citation
  • 11

    Juvela S: Unruptured aneurysms.. J Neurosurg 96:5860, 2002. (Editorial)

  • 12

    Juvela S, , Porras M, & Heiskanen O: Natural history of unruptured aneurysms: a long-term follow-up study. J Neurosurg 79:174182, 1993

  • 13

    Kassell NF, & Torner JC: The International Cooperative Study on Timing of Aneurysm Surgery—an update. Stroke 15:566570, 1984

  • 14

    McCormick WF, Problems and pathogenesis of intracranial arterial aneurysms. Toole JF, , Moossy J, & Janeway R: Cerebral Vascular Diseases. New York, Grune & Stratton, 1971. 219231

    • Search Google Scholar
    • Export Citation
  • 15

    McCormick WF, & Acosta-Rua GJ: The size of intracranial saccular aneurysms. An autopsy study. J Neurosurg 33:422427, 1970

  • 16

    Phan TG, , Huston J III, , Brown RD Jr, , Wiebers DO, & Piepgras DG: Intracranial saccular aneurysm enlargement determined using serial magnetic resonance angiography. J Neurosurg 97:10231028, 2002

    • Search Google Scholar
    • Export Citation
  • 17

    Riina HA, & Spetzler RF: Unruptured aneurysms . J Neurosurg 96:6162, 2002

  • 18

    Rinkel GJ, , Djibuti M, , Algra A, & van Gijn J: Prevalence and risk of rupture of intracranial aneurysms: a systematic review. Stroke 29:251256, 1998

    • Search Google Scholar
    • Export Citation
  • 19

    Suga M, , Yamamoto Y, , Sunami N, , Abe T, & Kondo A: [Growth of asymptomatic unruptured aneurysms in follow-up study: report of three cases.] . No Shinkei Geka 31:303308, 2003

    • Search Google Scholar
    • Export Citation
  • 20

    Tsutsumi K, , Ueki K, , Morita A, & Kirino T: Risk of rupture from incidental cerebral aneurysms. J Neurosurg 93:550553, 2000

  • 21

    Ujiie H, , Sato K, , Onda H, , Oikawa A, , Kagawa M, & Takakura K, : Clinical analysis of incidentally discovered unruptured aneurysms. Stroke 24:18501856, 1993

    • Search Google Scholar
    • Export Citation
  • 22

    Vates GE, , Zabramski JM, , Spetzler RF, & Lawton MT, Intracranial aneurysms. Mohr JP, , Choi DW, & Grotta JC, : Stroke: Pathophysiology, Diagnosis, and Management, ed 4. Philadelphia, Churchill Livingstone, 2004. 12791335

    • Search Google Scholar
    • Export Citation
  • 23

    Weir B: Unruptured intracranial aneurysms: a review. J Neurosurg 96:342, 2002

  • 24

    Weir B, , Amidei C, , Kongable G, , Findlay JM, , Kassell NF, & Kelly J, : The aspect ratio (dome/neck) of ruptured and unruptured aneurysms. J Neurosurg 99:447451, 2003

    • Search Google Scholar
    • Export Citation
  • 25

    Weir B, , Disney L, & Karrison T: Sizes of ruptured and unruptured aneurysms in relation to their sites and the ages of patients. J Neurosurg 96:6470, 2002

    • Search Google Scholar
    • Export Citation
  • 26

    White PM, & Wardlaw J: Unruptured intracranial aneurysms: prospective data have arrived. Lancet 362:9091, 2003

  • 27

    Wiebers DO, , Piepgras DG, , Brown RD Jr, , Meissner I, , Torner J, & Kassell NF, : Unruptured aneurysms. J Neurosurg 96:5051, 5860, 2002

  • 28

    Wiebers DO, , Whisnant JP, , Huston J III, , Meissner I, , Brown RD Jr, & Piepgras DG, : Unruptured intracranial aneurysms: natural history, clinical outcome, and risks of surgical and endovascular treatment. Lancet 362:103110, 2003

    • Search Google Scholar
    • Export Citation
  • 29

    Winn HR: Section overview: unruptured aneurysms. J Neurosurg 96:12, 2002

  • 30

    Winn HR, , Jane JA Sr, , Taylor J, , Kaiser D, & Britz GW: Prevalence of asymptomatic incidental aneurysms: review of 4568 arteriograms. J Neurosurg 96:4349, 2002

    • Search Google Scholar
    • Export Citation

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