Correspondence
Cerebral Aneurysms
N Engl J Med 2006; 355:2703-2705December 21, 2006
- Article
To the Editor:
Hyponatremia, a common and important complication of subarachnoid hemorrhage, is not mentioned in the review of cerebral aneurysms by Brisman et al. (Aug. 31 issue).1 Hyponatremia is associated with substantially increased morbidity among neurosurgical patients. A recent study2 indicated that hyponatremia developed in 66% of patients who underwent aneurysmal clipping and 62% of patients who underwent coiling after subarachnoid hemorrhage. The pathophysiology of hyponatremia is often complex and should influence the treatment approach. Clinicians should be aware of the importance of this problem so that appropriate measures can be implemented to correct hyponatremia in a timely fashion.
2 ReferencesFrancis M. Finucane, M.B.
Medical Research Council Epidemiology Unit, Cambridge CB1 9NL, United Kingdom
francis.finucane@mrc-epid. cam. ac. uk 1
Brisman JL ,Song JK ,Newell DW . Cerebral aneurysms. N Engl J Med 2006;355:928-939
Full Text | Web of Science | Medline2
Sherlock M ,O'Sullivan E ,Agha A , et al. The incidence and pathophysiology of hyponatraemia after subarachnoid haemorrhage. Clin Endocrinol (Oxf) 2006;64:250-254
CrossRef | Web of Science | Medline
To the Editor:
In their review article, Brisman et al. state that 5 to 40% of patients with autosomal dominant polycystic kidney disease have intracranial aneurysms and that screening with intracranial magnetic resonance angiography is indicated for all these patients. In studies of patients with autosomal dominant polycystic kidney disease, prospective screening detected intracranial aneurysms in 16% of 77 patients with a family history of intracranial aneurysms and in 6% of 186 patients without such a family history.1 All these aneurysms were small (mean diameter, 3.5 mm; range, 1 to 7); most were in the anterior circulation. According to the International Study of Unruptured Intracranial Aneurysms, the expected rupture rate is very low.2 Among patients with autosomal dominant polycystic kidney disease, no ruptures occurred during a decade of follow-up in 27 patients with intracranial aneurysms detected by screening that were smaller than 7 mm; two aneurysms increased in size.3 Repeat imaging after 9 years 10 months showed new aneurysms in 1 of 76 patients with negative results on initial screening.4
The claim for universal screening in autosomal dominant polycystic kidney disease is based on a 1996 decision-analysis study5 that used a 15.0% prevalence for intracranial aneurysms and a 1.6% annual rupture rate. Other analyses of at-risk populations have shown a marginal benefit or none.
In our practice, indications for screening patients with autosomal dominant polycystic kidney disease who have a good life expectancy are a family history of intracranial aneurysms, previous rupture of an aneurysm, major elective surgery, a high-risk occupation, and anxiety on the part of the patient despite adequate information.
5 ReferencesVicente E. Torres, M.D.
Mayo Clinic College of Medicine, Rochester, MN 55905
torres.vicente@mayo. edu Yves Pirson, M.D.
Université Catholique de Louvain, B-1200 Brussels, BelgiumDavid O. Wiebers, M.D.
Mayo Clinic College of Medicine, Rochester, MN 559051
Pirson Y ,Chauveau D ,Torres VE . Management of cerebral aneurysms in autosomal dominant polycystic kidney disease. J Am Soc Nephrol 2002;13:269-276
Web of Science | Medline2
Wiebers DO ,Whisnant JP ,Huston J III , et al. Unruptured intracranial aneurysms: natural history, clinical outcome, and risks of surgical and endovascular treatment. Lancet 2003;362:103-110
CrossRef | Web of Science | Medline3
Gibbs GF ,Huston J III ,Qian Q , et al. Follow-up of intracranial aneurysms in autosomal-dominant polycystic kidney disease. Kidney Int 2004;65:1621-1627
CrossRef | Web of Science | Medline4
Schrier RW ,Belz MM ,Johnson AM , et al. Repeat imaging for intracranial aneurysms in patients with autosomal dominant polycystic kidney disease with initially negative studies: a prospective ten-year follow-up. J Am Soc Nephrol 2004;15:1023-1028
CrossRef | Web of Science | Medline5
Butler WE ,Barker FG II ,Crowell RM . Patients with polycystic kidney disease would benefit from routine magnetic resonance angiographic screening for intracerebral aneurysms: a decision analysis. Neurosurgery 1996;38:506-516
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To the Editor:
Brisman et al. recommend the use of the Hunt and Hess Scale in the assessment of patients with recent subarachnoid hemorrhage. However, this clinical scale has poor interobserver reliability1 and does not predict the outcome well. Furthermore, the Hunt and Hess Scale measures both headache and neck stiffness, neither of which has prognostic significance and both of which can be difficult to assess reproducibly.
The World Federation of Neurosurgical Societies has devised a preferable scale (Table 1Table 1
Grading Scales for Subarachnoid Hemorrhage.). It has reasonable interobserver reliability, is a potent predictor of the outcome in both randomized, controlled trials and observational cohorts,2 and is based on the Glasgow Coma Scale, which is familiar to most clinicians.2 ReferencesWilliam Whiteley, M.A., M.R.C.P.
Rustam Al-Shahi Salman, Ph.D., M.R.C.P.
Western General Hospital, Edinburgh EH4 2XU, United Kingdom
wwhitele@staffmail.ed. ac. uk 1
Lindsay KW ,Teasdale G ,Knill-Jones RP ,Murray L . Observer variability in grading patients with subarachnoid hemorrhage. J Neurosurg 1982;56:628-633
CrossRef | Web of Science | Medline2
Al-Shahi R ,White PM ,Davenport RJ ,Lindsay KW . Subarachnoid haemorrhage. BMJ 2006;333:235-240
CrossRef | Web of Science | Medline
Author/Editor Response
We agree with Finucane that it is important to monitor and treat hyponatremia after a ruptured cerebral aneurysm. He cites a study that showed fewer instances of hyponatremia among patients with spontaneous subarachnoid hemorrhage who were treated conservatively than among those who were treated with clipping or coiling.1 The group treated conservatively, however, consisted mostly of patients with subarachnoid hemorrhage in which an aneurysm could not be detected. The natural history of nonaneurysmal subarachnoid hemorrhage usually differs from that of aneurysmal subarachnoid hemorrhage. Hyponatremia is infrequently the cause of significant impairment or death in patients with subarachnoid hemorrhage. For example, one recent multicenter review showed that hyponatremia had no bearing on the outcome 3 months after subarachnoid hemorrhage.2
Torres et al. share their algorithm for screening patients with autosomal dominant polycystic kidney disease. Although the incidence of cerebral aneurysms in the population with this disease is generally thought to be higher than that in the population without this disease, estimates of the prevalence have varied considerably. On the basis of currently available data, the screening approach outlined by Torres and colleagues appears to be reasonable.
Whiteley and Al-Shahi point out the importance of the World Federation of Neurosurgical Societies Scale for subarachnoid hemorrhage. More than 30 clinical grading scales for subarachnoid hemorrhage have been described. The most commonly used scales are the World Federation of Neurosurgical Societies Scale and the Hunt and Hess Scale. Both have reasonable interobserver reliability and correlate well with the ultimate clinical outcome.3 Despite the recommendations of the World Federation of Neurological Surgeons to use their scale as a universal scale, most neurosurgeons still prefer the Hunt and Hess Scale; in a review of articles on subarachnoid hemorrhage that were published between 1985 and 1992, 71% of reported studies used the Hunt and Hess Scale, whereas only 19% used the World Federation of Neurosurgical Societies Scale.4
4 ReferencesJonathan L. Brisman, M.D.
JFK Medical Center, Edison, NJ 08818
jbrisman@solarishs.org Joon K. Song, M.D.
Roosevelt Medical Center, New York, NY 10019David W. Newell, M.D.
Swedish Medical Center, Seattle, WA 981221
Sherlock M ,O'Sullivan E ,Agha A , et al. The incidence and pathophysiology of hyponatraemia after subarachnoid haemorrhage. Clin Endocrinol (Oxf) 2006;64:250-254
CrossRef | Web of Science | Medline2
Qureshi AI ,Suri MF ,Sung GY , et al. Prognostic significance of hypernatremia and hyponatremia among patients with aneurysmal subarachnoid hemorrhage. Neurosurgery 2002;50:749-755
CrossRef | Web of Science | Medline3
Oshiro EM ,Walter KA ,Piantadosi S ,Witham TF ,Tamargo RJ . A new subarachnoid hemorrhage grading system based on the Glasgow Coma Scale: a comparison with the Hunt and Hess and World Federation of Neurological Surgeons Scales in a clinical series. Neurosurgery 1997;41:140-147
CrossRef | Web of Science | Medline4
van Gijn J ,Bromberg JE ,Lindsay KW ,Hasan D ,Vermeulen M . Definition of initial grading, specific events, and overall outcome in patients with aneurysmal subarachnoid hemorrhage: a survey. Stroke 1994;25:1623-1627
CrossRef | Web of Science | Medline
