Correspondence

Fibromuscular Dysplasia

N Engl J Med 2004; 351:509-510July 29, 2004

Article

To the Editor:

Slovut and Olin (April 29 issue)1 provide a valuable review of the current concepts of fibromuscular dysplasia. To their discussion regarding the craniocervical arteries should be added the topic of intracranial aneurysms and subarachnoid hemorrhage related to fibromuscular dysplasia. In our experience, more or less pronounced angiographic signs of fibromuscular dysplasia are frequently apparent in the context of ruptured and unruptured intracranial aneurysms. The numbers in the literature for the incidence of unruptured aneurysms in patients with fibromuscular dysplasia vary widely, from 7 percent to more than 50 percent.2 Specific forms of intracranial aneurysms such as giant and dissecting aneurysms and multiple aneurysms appear to be particularly associated with fibromuscular dysplasia.3,4 The practical importance of fibromuscular dysplasia for the management of intracranial aneurysms remains unclear. Complications associated with endovascular catheterization (i.e., vasospasm and dissections) may be more frequent, as well as later development of new aneurysms.5

Hans J. Steiger, M.D.
Bernd Turowski, M.D.
University Hospital Düsseldorf, D-40225 Düsseldorf, Germany
steiger@uni-duesseldorf.de

5 References

1. 1

   Slovut DP, Olin JW. Fibromuscular dysplasia. N Engl J Med 2004;350:1862-1871
   Full Text | Web of Science | Medline

2. 2

   Cloft HJ, Kallmes DF, Kallmes MH, Goldstein JH, Jensen ME, Dion JE. Prevalence of cerebral aneurysms in patients with fibromuscular dysplasia: a reassessment. J Neurosurg 1998;88:436-440
   CrossRef | Web of Science | Medline

3. 3

   Schievink WI, Puumala MR, Meyer FB, Raffel C, Katzmann JA, Parisi JE. Giant intracranial aneurysm and fibromuscular dysplasia in an adolescent with alpha 1-antitrypsin deficiency. J Neurosurg 1996;85:503-506
   CrossRef | Web of Science | Medline

4. 4

   Pilz P, Hartjes HJ. Fibromuscular dysplasia and multiple dissecting aneurysms of intracranial arteries: a further cause of Moyamoya syndrome. Stroke 1976;7:393-398
   CrossRef | Web of Science | Medline

5. 5

   Nakamura M, Rosahl SK, Vorkapic P, Forster C, Samii M. De novo formation of an aneurysm in a case of unusual intracranial fibromuscular dysplasia. Clin Neurol Neurosurg 2000;102:259-264
   CrossRef | Web of Science | Medline

Author/Editor Response

Drs. Steiger and Turowski make an important point regarding the association between fibromuscular dysplasia and intracranial aneurysms, for which the prevalence has been reported to be as high as 51 percent.1,2 However, the prevalence estimates may be falsely elevated because of selection bias; many of the patients with aneurysms in these series underwent angiography after presenting with subarachnoid hemorrhage. Fibromuscular dysplasia was an incidental finding in some of the reported cases.3

When patients who presented with subarachnoid hemorrhage are excluded from the prevalence estimates, the prevalence of incidental, asymptomatic cerebral aneurysms in patients with internal-carotid-artery or vertebral-artery fibromuscular dysplasia is only 7.3 percent.3 By comparison, a meta-analysis of 23 studies (with a total of 56,304 patients) showed a prevalence of intracranial aneurysms of 0.4 percent in retrospective autopsy series, 3.6 percent in prospective autopsy series, 3.7 percent in retrospective angiography studies, and 6.0 percent in prospective angiography studies; the annual risk of rupture was 0.7 percent.4 Given the wide variation in prevalence reported in the literature, we recommend routine screening with magnetic resonance angiography in all patients with cerebrovascular fibromuscular dysplasia.5

David P. Slovut, M.D., Ph.D.
Jeffrey W. Olin, D.O.
Mount Sinai School of Medicine, New York, NY 10029
jeffrey.olin@msnyuhealth.org

5 References

1. 1

   Mettinger KL. Fibromuscular dysplasia and the brain. II. Current concept of the disease. Stroke 1982;13:53-58
   CrossRef | Web of Science | Medline

2. 2

   George B, Mourier KL, Gelbert F, Reizine D, Raggueneau JL. Vascular abnormalities in the neck associated with intracranial aneurysms. Neurosurgery 1989;24:499-508
   CrossRef | Web of Science | Medline

3. 3

   Cloft HJ, Kallmes DF, Kallmes MH, Goldstein JH, Jensen ME, Dion JE. Prevalence of cerebral aneurysms in patients with fibromuscular dysplasia: a reassessment. J Neurosurg 1998;88:436-440
   CrossRef | Web of Science | Medline

4. 4

   Rinkel GJ, Djibuti M, Algra A, van Gijn J. Prevalence and risk of rupture of intracranial aneurysms: a systematic review. Stroke 1998;29:251-256
   CrossRef | Web of Science | Medline

5. 5

   Slovut DP, Olin JW. Fibromuscular dysplasia. N Engl J Med 2004;350:1862-1871
   Full Text | Web of Science | Medline