Published ahead of print on July 21, 2011
doi: 10.3174/ajnr.A2647
American Journal of Neuroradiology 32:E161, September 2011
© 2011 American Society of Neuroradiology
J. Linna
aDepartment of Neuroradiology
University Hospital Munich
Munich, Germany
With great interest I read the letter by Chandra et al1 referring to a review article by Cuvinciuc et al.2
Chandra et al1 present a 70-year-old male patient with a focal subarachnoid hemorrhage (fSAH) in the left central sulcus. They conclude that an 80% stenosis of the left internal carotid artery (ICA), resulting in a shift of the watershed between the middle cerebral artery and the posterior cerebral artery territories toward the central sulcus, was responsible for the fSAH. Undoubtedly, the potential pathomechanism proposed by the authors is of interest; however, it is not at all proved in this case. We would like to draw attention to an alternative cause of this fSAH, namely cerebral amyloid angiopathy (CAA).
There is more and more evidence that CAA is the most important cause of nontraumatic fSAHs in older patients.3,4 fSAHs in patients with CAA most often affect the central sulcus, and patients typically present with transient ischemic attack (TIA)–like symptoms.3,5 According to the authors, CAA has been excluded by MR imaging in their case. I conclude that they found no additionaltypical MR imaging signs of CAA, such as old micro- or macrobleeds.However, several studies have found that fSAH or superficial siderosis as a residue of fSAH can be the only pathologic MR imaging finding in patients with histologically proved CAA.5 We propose that the coincidence of ICA stenosis and fSAH could be incidental.
On the basis of the available data in the literature and taking into account the advanced age of the patient (70 years), thelocalization of the fSAH (in the central sulcus), and the clinical presentation with “recurrent events” of “transient aphasia anddysarthria, along with right face and arm numbness,” we regard CAA as the major differential diagnosis.
The consideration of CAA as the underlying cause in older patients with TIA-like symptoms and fSAH in the central sulcus is not only of academic interest, it also has a great clinical impact on patient management, especially in light of the risk of hemorrhagic complications of antiplatelet and anticoagulation therapy.
References
- Chandra RV, Leslie-Mazwi TM, Oh D, et al. Extracranial internal carotid artery stenosis as a cause of cortical subarachnoid hemorrhage. AJNR Am J Neuroradiol 2011;32:E51–E52. Epub 2011 Feb 24[Free Full Text]
- Cuvinciuc V, Viguier A, Calviere L, et al. Isolated acute nontraumatic cortical subarachnoid hemorrhage. AJNR Am J Neuroradiol 2010;31:1355–62. Epub 2010 Jan 21[Abstract/Free Full Text]
- Kumar N, Goddeau RP, Jr, Selim MH, et al. Atraumatic convexal subarachnoid hemorrhage: clinical presentation, imaging patterns, and etiologies. Neurology 2010;74:893–99[Abstract/Free Full Text]
- Raposo N, Viguier A, Cuvinciuc V, et al. Cortical subarachnoid haemorrhage in the elderly: a recurrent event probably related to cerebral amyloid angiopathy. Eur J Neurol 2011;18:597–603. Epub 2010 Oct 6[CrossRef][Medline]
- Linn J, Halpin A, Demaerel P, et al. Prevalence of superficial siderosis in patients with cerebral amyloid angiopathy. Neurology 2010;74:1346–50[Abstract/Free Full Text]
Reply
Published ahead of print on July 21, 2011
doi: 10.3174/ajnr.A2676
American Journal of Neuroradiology 32:E162, September 2011
© 2011 American Society of Neuroradiology
R.V. Chandraa, T.M. Leslie-Mazwia, D. Oha, A.J. Yooa and B. Mehtab
aDepartment of Interventional Neuroradiology/
Endovascular Neurosurgery
bDepartment of Neurocritical Care
Massachusetts General Hospital
Harvard Medical School
Boston, Massachusetts
We thank Dr Linn for her response to our letter entitled “Extracranial Internal Carotid Artery Stenosis as a Cause of Cortical Subarachnoid Hemorrhage.”1We certainly agree that cerebral amyloid angiopathy (CAA) is an important cause of focal sulcal subarachnoid hemorrhage (fsSAH) in the elderly. We further appreciate that patients with histologic evidence of CAA may manifest radiologically as having superficial siderosis (SS) without evidence of macro-or microbleeds.2 However, we disagree that CAA is the leading differential consideration in our particular case.
A recent study of the Boston criteria by Linn et al2 demonstrated that the addition of SS as a diagnostic criterion improves the sensitivity for identifying CAA-related hemorrhage to 94.7%. Therefore, in our case in which there was no MR imaging evidence of CAA (including no evidence of SS), the likelihood of CAA should be low if the study is correct. Unfortunately, the definitive diagnosis requires a histopathologic specimen, which was thought to be unnecessary and aggressive in a patient who did not meet criteria for “possible CAA” by using the Boston criteria.3
Moreover, the Boston criteria and the modified version proposed by Linn et al2 require that other causes of intracranial hemorrhage be excluded.3 As we have described in our letter, steno-occlusive disease is a recognized cause of fsSAH, which is supported by numerous reports in the literature.4–6 In fact, a recent article by Raposo et al,7 which examines the association of CAA and cortical SAH, excludes those patients with apparent causes of SAH including carotid occlusion.
We commend Dr Linn for her work on the “modified” Boston criteria2 to increase the sensitivity for the diagnosis of CAA and look forward to its further validation. However in our specific case, we maintain that our postulated hemodynamic cause is the likely mechanism for fsSAH.
References
- Chandra RV, Leslie-Mazwi TM, Oh D, et al. Extracranial internal carotid artery stenosis as a cause of cortical subarachnoid hemorrhage. AJNR Am J Neuroradiol 2011;32:E51–52. Epub 2011 Feb 24[Free Full Text]
- Linn J, Halpin A, Demaerel P, et al. Prevalence of superficial siderosis in patients with cerebral amyloid angiopathy. Neurology 2011;74:1346–50
- Knudsen KA, Rosand J, Karluk D, et al. Clinical diagnosis of cerebral amyloid angiopathy: validation of the Boston criteria. Neurology 2001;56:537–39[Abstract/Free Full Text]
- Cuvinciuc V, Viguier A, Calviere L, et al. Isolated acute nontraumatic cortical subarachnoid hemorrhage. AJNR Am J Neuroradiol 2010;31:1355–62. Epub 2010 Jan 21[Abstract/Free Full Text]
- Kleinig TJ, Kimber TE, Thompson PD. Convexity subarachnoid haemorrhage associated with bilateral internal carotid artery stenoses. J Neurol 2009;256:669–71[CrossRef][Medline]
- Geraldes R, Santos C, Canhao P. Atraumatic localized convexity subarachnoid hemorrhage associated with acute carotid artery occlusion. Eur J Neurol 2011;18:e28–29. Epub 2010 Sep 27[CrossRef][Medline]
- Raposo N, Viguier A, Cuvinciuc V, et al. Cortical subarachnoid haemorrhage in the elderly: A recurrent event probably related to cerebral amyloid angiopathy. Eur J Neurol 2011;18:597–603[CrossRef][Medline]