Daichi Nakagawa1, Cameron Cushing2, Yasunori Nagahama2, Lauren Allan3, David Hasan4. 1. Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA; Department of Biomedical Engineering, Seamans Center for the Engineering Arts and Sciences, University of Iowa, Iowa City, Iowa, USA. 2. Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA. 3. Department of General Surgery, Mercy Medical Center, Des Moines, Iowa, USA. 4. Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA. Electronic address: david-hasan@uiowa.edu.
Abstract
BACKGROUND: Sentinel headache (SH) occurs before aneurysm rupture in an estimated 15%-60% of cases of aneurysmal subarachnoid hemorrhage (aSAH). By definition, noncontrast computed tomography (CT) scan of the brain and lumbar puncture are both negative in patients presenting with SH. One of the theories explaining this phenomenon is that microhemorrhage (MH) from the aneurysm wall contribute to iron deposition in the interface between the aneurysm wall and brain parenchyma. Quantitative susceptibility mapping (QSM) is a recently introduced magnetic resonance imaging (MRI) technique that has proven capable of localizing the deposition of paramagnetic metals, particularly ferric iron. Thus, the QSM sequence may be able to detect iron deposition secondary to MH. CASE DESCRIPTION: A 76-year-old male presented with the "worst headache of my life." Noncontrast head CT scan and lumbar puncture were negative. Magnetic resonance angiography (MRA) of the brain revealed an anterior communicating artery (A-com) aneurysm measuring 7 mm with a large bleb. T1-weighted imaging (WI), T2-WI, MRA, T2 star-weighted angiography (SWAN), and QSM sequences were obtained. T2-WI, SWAN, and QSM revealed isointense, hypointense, and hyperintense signals, respectively, at the interface of the aneurysm wall and brain tissue. These findings were consistent with deposition of ferric iron at this interface. The A-com aneurysm was treated with coil embolization, and the patient exhibited no postoperative deficits. CONCLUSIONS: The MRI QSM sequence can localize iron deposition resulting from MH within an aneurysmal wall. This sequence may be a promising imaging tool for screening patients presenting with SH.
BACKGROUND: Sentinel headache (SH) occurs before aneurysm rupture in an estimated 15%-60% of cases of aneurysmal subarachnoid hemorrhage (aSAH). By definition, noncontrast computed tomography (CT) scan of the brain and lumbar puncture are both negative in patients presenting with SH. One of the theories explaining this phenomenon is that microhemorrhage (MH) from the aneurysm wall contribute to iron deposition in the interface between the aneurysm wall and brain parenchyma. Quantitative susceptibility mapping (QSM) is a recently introduced magnetic resonance imaging (MRI) technique that has proven capable of localizing the deposition of paramagnetic metals, particularly ferric iron. Thus, the QSM sequence may be able to detect iron deposition secondary to MH. CASE DESCRIPTION: A 76-year-old male presented with the "worst headache of my life." Noncontrast head CT scan and lumbar puncture were negative. Magnetic resonance angiography (MRA) of the brain revealed an anterior communicating artery (A-com) aneurysm measuring 7 mm with a large bleb. T1-weighted imaging (WI), T2-WI, MRA, T2 star-weighted angiography (SWAN), and QSM sequences were obtained. T2-WI, SWAN, and QSM revealed isointense, hypointense, and hyperintense signals, respectively, at the interface of the aneurysm wall and brain tissue. These findings were consistent with deposition of ferric iron at this interface. The A-com aneurysm was treated with coil embolization, and the patient exhibited no postoperative deficits. CONCLUSIONS: The MRI QSM sequence can localize iron deposition resulting from MH within an aneurysmal wall. This sequence may be a promising imaging tool for screening patients presenting with SH.
Authors: Daichi Nakagawa; Kohsuke Kudo; Olatilewa Awe; Mario Zanaty; Yasunori Nagahama; Cameron Cushing; Vincent Magnotta; Minako Hayakawa; Lauren Allan; Jeremy Greenlee; Issam A Awad; Timothy Carroll; James Torner; Madhavan L Raghavan; David M Hasan Journal: J Neurosurg Date: 2018-05-01 Impact factor: 5.115
Authors: Daizo Ishii; Daichi Nakagawa; Mario Zanaty; Jorge A Roa; Sami Al Kasab; Amir Shaban; Joseph S Hudson; Carlos Osorno-Cruz; Stefano Byer; Lauren Allan; James C Torner; Issam A Awad; Timothy J Carroll; Edgar A Samaniego; David M Hasan Journal: J Clin Med Date: 2020-04-01 Impact factor: 4.241