OBJECTIVE: To determine the frequency and characteristics of microembolic signals (MES) in subarachnoid hemorrhage (SAH). METHODS: Twenty-three patients with aneurysmal SAH were monitored with transcranial Doppler ultrasonography for the presence of MES and vasospasm. Each middle cerebral artery was monitored for 30 minutes three times each week. Patients were excluded if they had traumatic SAH or cardiac or arterial sources of emboli. Monitoring was initiated 6.3 days (1-16 d) after SAH and lasted 6.6 days (1-13 d). Eleven individuals without SAH or other cerebrovascular diseases who were treated in the same unit served as control subjects. Each patient underwent monitoring of both middle cerebral arteries a mean of three times; therefore, 46 vessels were studied (a total of 138 observations). Control subjects underwent assessment of each middle cerebral artery once, for a total of 22 control vessels. RESULTS: MES were detected for 16 of 23 patients (70%) and 44 of 138 patient vessels (32%) monitored, compared with 2 of 11 control subjects (18%) and 2 of 22 control vessels (9%) (P < 0.05). MES were observed for 83% of patients with clinical vasospasm and 54% of those without clinical vasospasm. Ultrasonographic vasospasm was observed for 71 of 138 vessels monitored; MES were observed for 28% of vessels with vasospasm and 36% of those without vasospasm. Aneurysms proximal to the monitored artery were identified in 38 of 138 vessels, of which 34% exhibited MES, which is similar to the frequency for vessels without proximal aneurysms (31%). Coiled, clipped, and unsecured aneurysms exhibited similar frequencies of MES. CONCLUSION: MES were common in SAH, occurring in 70% of cases of SAH and one-third of all vessels monitored. Although MES were more frequent among patients with clinical vasospasm, this difference did not reach statistical significance. We were unable to demonstrate a relationship between ultrasonographic vasospasm and MES, and the presence of a proximal secured or unsecured aneurysm did not alter the chance of detection of MES. Further studies are required to determine the origin and clinical relevance of MES in SAH.
OBJECTIVE: To determine the frequency and characteristics of microembolic signals (MES) in subarachnoid hemorrhage (SAH). METHODS: Twenty-three patients with aneurysmalSAH were monitored with transcranial Doppler ultrasonography for the presence of MES and vasospasm. Each middle cerebral artery was monitored for 30 minutes three times each week. Patients were excluded if they had traumatic SAH or cardiac or arterial sources of emboli. Monitoring was initiated 6.3 days (1-16 d) after SAH and lasted 6.6 days (1-13 d). Eleven individuals without SAH or other cerebrovascular diseases who were treated in the same unit served as control subjects. Each patient underwent monitoring of both middle cerebral arteries a mean of three times; therefore, 46 vessels were studied (a total of 138 observations). Control subjects underwent assessment of each middle cerebral artery once, for a total of 22 control vessels. RESULTS:MES were detected for 16 of 23 patients (70%) and 44 of 138 patient vessels (32%) monitored, compared with 2 of 11 control subjects (18%) and 2 of 22 control vessels (9%) (P < 0.05). MES were observed for 83% of patients with clinical vasospasm and 54% of those without clinical vasospasm. Ultrasonographic vasospasm was observed for 71 of 138 vessels monitored; MES were observed for 28% of vessels with vasospasm and 36% of those without vasospasm. Aneurysms proximal to the monitored artery were identified in 38 of 138 vessels, of which 34% exhibited MES, which is similar to the frequency for vessels without proximal aneurysms (31%). Coiled, clipped, and unsecured aneurysms exhibited similar frequencies of MES. CONCLUSION:MES were common in SAH, occurring in 70% of cases of SAH and one-third of all vessels monitored. Although MES were more frequent among patients with clinical vasospasm, this difference did not reach statistical significance. We were unable to demonstrate a relationship between ultrasonographic vasospasm and MES, and the presence of a proximal secured or unsecured aneurysm did not alter the chance of detection of MES. Further studies are required to determine the origin and clinical relevance of MES in SAH.
Authors: Jared M Pisapia; Xiangsheng Xu; Jane Kelly; Jamie Yeung; Geneive Carrion; Huaiyu Tong; Sudha Meghan; Omar M El-Falaky; M Sean Grady; Douglas H Smith; Sergei Zaitsev; Vladimir R Muzykantov; Michael F Stiefel; Sherman C Stein Journal: Exp Neurol Date: 2011-11-04 Impact factor: 5.330
Authors: J Caspers; C Rubbert; B Turowski; D Martens; D C Reichelt; R May; J Aissa; D Hänggi; N Etminan; C Mathys Journal: Clin Neuroradiol Date: 2015-05-05 Impact factor: 3.649
Authors: Jasper H van Lieshout; Maxine Dibué-Adjei; Jan F Cornelius; Philipp J Slotty; Toni Schneider; Tanja Restin; Hieronymus D Boogaarts; Hans-Jakob Steiger; Athanasios K Petridis; Marcel A Kamp Journal: Neurosurg Rev Date: 2017-02-18 Impact factor: 3.042
Authors: F Cagnazzo; I Derraz; P-H Lefevre; G Gascou; C Dargazanli; C Riquelme; P Perrini; D di Carlo; A Bonafe; V Costalat Journal: AJNR Am J Neuroradiol Date: 2019-06-06 Impact factor: 3.825
Authors: Eva A Rocha; Felipe Rocha; Izadora Deliberalli; João Brainer C de Andrade; Irapuá F Ricarte; Aneesh B Singhal; Gisele S Silva Journal: Neurocrit Care Date: 2020-08-07 Impact factor: 3.210