{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:42:42Z","timestamp":1760060562990,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2025,9,3]],"date-time":"2025-09-03T00:00:00Z","timestamp":1756857600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Open Access Publishing Fund of Leipzig University"},{"name":"German Research Foundation within the Open Access Pub"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: Delayed cerebral ischemia (DCI) after an aneurysmal subarachnoid hemorrhage (aSAH) often presents with bilateral vasospasm and cortical spreading depolarizations. Computer tomography perfusion (CTP) is the prevailing screening method for detecting early changes in the cerebral blood flow. Commonly used CTP thresholds include an rCBF &lt; 30% for the core volume and a Tmax &gt; 6 s for hypoperfused tissue detection in acute ischemic stroke. These stroke algorithm computing thresholds compared to the contralateral hemisphere may or may not apply to detect tissue at risk of DCI. We aimed to quantify the volumetric agreement of three different stroke algorithms compared to the final infarct volumes as the standard. Methods: Furthermore, 123 CTP datasets of 75 patients with aSAH suspicious of DCI were processed using Intellispace Portal (ISP), Cercare Threshold, and Cercare Artificial Intelligence (AI) to calculate the tissue-at-risk (hypoperfused) and non-viable tissue (core) volumes. CT infarct volumes in plain CTs were segmented in the follow-up study by using a 3D slicer. Results: The calculated core volumes corresponded best to the final infarct volumes if DCI-related treatment was performed subsequently. Additional postprocessing improved the calculation of core volumes but overestimated the tissue at risk of hypoperfusion in DCI. Whereas the accuracy of tissue-at-risk prediction accelerated without treatment, underlining the importance of intra-arterial spasmolysis and induced hypertension in the prevention of DCI. Conclusions: Cercare AI and ISP revealed a sensitivity of 100% each, with a serious low specificity of &lt;5% that was independent of treatment. Overall, the Cercare Threshold, applying the commonly used stroke thresholds, performed the best in predicting tissue at risk of hypoperfusion in DCI.<\/jats:p>","DOI":"10.3390\/diagnostics15172236","type":"journal-article","created":{"date-parts":[[2025,9,3]],"date-time":"2025-09-03T12:07:32Z","timestamp":1756901252000},"page":"2236","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Comparison of Three Perfusion Algorithms in Patients at Risk of Delayed Cerebral Ischemia After Subarachnoid Hemorrhage"],"prefix":"10.3390","volume":"15","author":[{"given":"Lea Katharina","family":"Falter","sequence":"first","affiliation":[{"name":"Department of Neuroradiology, Leipzig University Hospital, Liebigstr. 20, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9662-3733","authenticated-orcid":false,"given":"Dirk","family":"Halama","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Leipzig University Hospital, Liebigstr. 20, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cordula","family":"Scherlach","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Leipzig University Hospital, Liebigstr. 20, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3749-2494","authenticated-orcid":false,"given":"Felix","family":"Arlt","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Leipzig University Hospital, Liebigstr. 20, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0595-2698","authenticated-orcid":false,"given":"Kristin","family":"Starke","sequence":"additional","affiliation":[{"name":"Department of Neurology, Leipzig University Hospital, Liebigstr. 20, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karl-Titus","family":"Hoffmann","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Leipzig University Hospital, Liebigstr. 20, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5105-9676","authenticated-orcid":false,"given":"Cindy","family":"Richter","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Leipzig University Hospital, Liebigstr. 20, 04103 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1118","DOI":"10.1212\/WNL.0000000000003091","article-title":"Incidence of subarachnoid hemorrhage is decreasing together with decreasing smoking rates","volume":"87","author":"Korja","year":"2016","journal-title":"Neurology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1001\/jamaneurol.2019.0006","article-title":"Worldwide Incidence of Aneurysmal Subarachnoid Hemorrhage According to Region, Time Period, Blood Pressure, and Smoking Prevalence in the Population: A Systematic Review and Meta-analysis","volume":"76","author":"Etminan","year":"2019","journal-title":"JAMA Neurol."},{"key":"ref_3","first-page":"e314","article-title":"2023 Guideline for the Management of Patients With Aneurysmal Subarachnoid Hemorrhage: A Guideline From the American Heart Association\/American Stroke Association","volume":"54","author":"Hoh","year":"2023","journal-title":"Stroke"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"242","DOI":"10.1177\/17474930221093501","article-title":"Fight INflammation to Improve outcome after aneurysmal Subarachnoid HEmorRhage (FINISHER) trial: Study protocol for a randomized controlled trial","volume":"18","author":"Lampmann","year":"2023","journal-title":"Int. J. Stroke"},{"key":"ref_5","first-page":"593","article-title":"Prophylactic hyperdynamic postoperative fluid therapy after aneurysmal subarachnoid hemorrhage: A clinical, prospective, randomized, controlled study","volume":"49","author":"Egge","year":"2001","journal-title":"Neurosurgery"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"383","DOI":"10.1161\/01.STR.31.2.383","article-title":"Effect of hypervolemic therapy on cerebral blood flow after subarachnoid hemorrhage: A randomized controlled trial","volume":"31","author":"Lennihan","year":"2000","journal-title":"Stroke"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"809","DOI":"10.1016\/S0140-6736(05)67214-5","article-title":"International subarachnoid aneurysm trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: A randomised comparison of effects on survival, dependency, seizures, rebleeding, subgroups, and aneurysm occlusion","volume":"366","author":"Molyneux","year":"2005","journal-title":"Lancet"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1016\/S0140-6736(20)32518-6","article-title":"Ultra-early tranexamic acid after subarachnoid haemorrhage (ULTRA): A randomised controlled trial","volume":"397","author":"Post","year":"2021","journal-title":"Lancet"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"597","DOI":"10.1007\/s12975-019-00713-y","article-title":"Inflammation: A Good Research Target to Improve Outcomes of Poor-Grade Subarachnoid Hemorrhage","volume":"10","author":"Suzuki","year":"2019","journal-title":"Transl. Stroke Res."},{"key":"ref_10","first-page":"939","article-title":"Evaluation of vasospasm after subarachnoid hemorrhage by use of multislice computed tomographic angiography","volume":"51","author":"Otawara","year":"2002","journal-title":"Neurosurgery"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1007\/s11883-017-0690-x","article-title":"Delayed Cerebral Ischemia after Subarachnoid Hemorrhage: Beyond Vasospasm and Towards a Multifactorial Pathophysiology","volume":"19","author":"Geraghty","year":"2017","journal-title":"Curr. Atheroscler. Rep."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1038\/nm.2333","article-title":"The role of spreading depression, spreading depolarization and spreading ischemia in neurological disease","volume":"17","author":"Dreier","year":"2011","journal-title":"Nature Med."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Merkel, H., Lindner, D., Gaber, K., Ziganshyna, S., Jentzsch, J., Mucha, S., Gerhards, T., Sari, S., Stock, A., and Vothel, F. (2022). Standardized Classification of Cerebral Vasospasm after Subarachnoid Hemorrhage by Digital Subtraction Angiography. J. Clin. Med., 11.","DOI":"10.3390\/jcm11072011"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2391","DOI":"10.1161\/STROKEAHA.110.589275","article-title":"Definition of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage as an outcome event in clinical trials and observational studies: Proposal of a multidisciplinary research group","volume":"41","author":"Vergouwen","year":"2010","journal-title":"Stroke"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1257","DOI":"10.3171\/2015.4.JNS15428","article-title":"Vasospasm on transcranial Doppler is predictive of delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage: A systematic review and meta-analysis","volume":"124","author":"Kumar","year":"2016","journal-title":"J. Neurosurg."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"708","DOI":"10.1056\/NEJMoa1713973","article-title":"Thrombectomy for Stroke at 6 to 16 Hours with Selection by Perfusion Imaging","volume":"378","author":"Albers","year":"2018","journal-title":"N. Engl. J. Med."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1056\/NEJMoa1706442","article-title":"Thrombectomy 6 to 24 Hours after Stroke with a Mismatch between Deficit and Infarct","volume":"378","author":"Nogueira","year":"2018","journal-title":"N. Engl. J. Med."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"875","DOI":"10.1002\/ana.25479","article-title":"Penumbra detection in acute stroke with perfusion magnetic resonance imaging: Validation with 15 O-positron emission tomography","volume":"85","author":"Fleischer","year":"2019","journal-title":"Ann. Neurol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1780","DOI":"10.1177\/0271678X15610586","article-title":"A benchmarking tool to evaluate computer tomography perfusion infarct core predictions against a DWI standard","volume":"36","author":"Cereda","year":"2016","journal-title":"J. Cereb. Blood Flow Metab."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1401","DOI":"10.2214\/AJR.21.26139","article-title":"Automated Processing of Head CT Perfusion Imaging for Ischemic Stroke Triage: A Practical Guide to Quality Assurance and Interpretation","volume":"217","author":"Chung","year":"2021","journal-title":"Am. J. Roentgenol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1017","DOI":"10.1161\/STROKEAHA.119.028337","article-title":"Review of Perfusion Imaging in Acute Ischemic Stroke: From Time to Tissue","volume":"51","author":"Demeestere","year":"2020","journal-title":"Stroke"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1407","DOI":"10.3174\/ajnr.A4303","article-title":"Perfusion Deficits and Mismatch in Patients with Acute Lacunar Infarcts Studied with Whole-Brain CT Perfusion","volume":"36","author":"Rudilosso","year":"2015","journal-title":"Am. J. Neuroradiol."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Pennig, L., Thiele, F., Goertz, L., Laukamp, K.R., Perkuhn, M., Kabbasch, C., Schlamann, M., Fink, G.R., and Borggrefe, J. (2020). Comparison of Accuracy of Arrival-Time-Insensitive and Arrival-Time-Sensitive CTP Algorithms for Prediction of Infarct Tissue Volumes. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-66041-6"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Koopman, M.S., Hoving, J.W., Tolhuisen, M.L., Jin, P., Thiele, F.O., Bremer-van der Heiden, L., van Voorst, H., Berkhemer, O.A., Coutinho, J.M., and Beenen, L.F.M. (2023). Accuracy of Four Different CT Perfusion Thresholds for Ischemic Core Volume and Location Estimation Using IntelliSpace Portal. J. Cardiovasc. Dev. Dis., 10.","DOI":"10.3390\/jcdd10060239"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1249","DOI":"10.1136\/neurintsurg-2019-014822","article-title":"Comparison of three commonly used CT perfusion software packages in patients with acute ischemic stroke","volume":"11","author":"Koopman","year":"2019","journal-title":"J. Neurointerv. Surg."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"206","DOI":"10.3174\/ajnr.A6395","article-title":"Assessment of a Bayesian Vitrea CT Perfusion Analysis to Predict Final Infarct and Penumbra Volumes in Patients with Acute Ischemic Stroke: A Comparison with RAPID","volume":"41","author":"Rava","year":"2020","journal-title":"Am. J. Neuroradiol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"781","DOI":"10.1136\/jnnp-2023-331513","article-title":"Endovascular treatment for large-core ischaemic stroke: A meta-analysis of randomised controlled clinical trials","volume":"94","author":"Palaiodimou","year":"2023","journal-title":"J. Neurol. Neurosurg. Psychiatry"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Lolli, V.E., Guenego, A., Sadeghi, N., Jodaitis, L., Lubicz, B., Taccone, F.S., and Gouvea Bogossian, E. (2024). CT perfusion imaging in aneurysmal subarachnoid hemorrhage. State of the art. Front. Radiol., 4.","DOI":"10.3389\/fradi.2024.1445676"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1053\/j.sult.2006.02.004","article-title":"Using CT in the diagnosis and management of patients with cerebral vasospasm","volume":"27","author":"Sanelli","year":"2006","journal-title":"Semin. Ultrasound CT MR"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"3493","DOI":"10.1161\/STROKEAHA.109.559013","article-title":"Diagnosing delayed cerebral ischemia with different CT modalities in patients with subarachnoid hemorrhage with clinical deterioration","volume":"40","author":"Dankbaar","year":"2009","journal-title":"Stroke"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1862","DOI":"10.1161\/01.STR.0000133132.76983.8e","article-title":"Predictors of cerebral infarction in aneurysmal subarachnoid hemorrhage","volume":"35","author":"Rabinstein","year":"2004","journal-title":"Stroke"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1007\/s00062-015-0399-6","article-title":"Timing of Mean Transit Time Maximization is Associated with Neurological Outcome After Subarachnoid Hemorrhage","volume":"27","author":"Caspers","year":"2017","journal-title":"Clin. Neuroradiol."},{"key":"ref_33","first-page":"26","article-title":"Vasospasm after subarachnoid hemorrhage: Utility of perfusion CT and CT angiography on diagnosis and management","volume":"27","author":"Wintermark","year":"2006","journal-title":"Am. J. Neuroradiol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"3107","DOI":"10.1007\/s10143-021-01509-1","article-title":"Intravenous milrinone for treatment of delayed cerebral ischaemia following subarachnoid haemorrhage: A pooled systematic review","volume":"44","author":"Lai","year":"2021","journal-title":"Neurosurg. Rev."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"138","DOI":"10.1097\/CNQ.0000000000000299","article-title":"Pharmacologic Management of Cerebral Vasospasm in Aneurysmal Subarachnoid Hemorrhage","volume":"43","author":"Smetana","year":"2020","journal-title":"Crit. Care Nurs. Q."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/0163-7258(95)00025-9","article-title":"Calcium channels in cerebral arteries","volume":"68","author":"Alborch","year":"1995","journal-title":"Pharmacol. Ther."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"206","DOI":"10.2174\/187152509789105453","article-title":"Phosphodiesterase 3 (PDE3): Structure, localization and function","volume":"7","author":"Murata","year":"2009","journal-title":"Cardiovasc. Hematol. Agents Med. Chem."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"735","DOI":"10.1161\/01.STR.20.6.735","article-title":"Early collateral blood supply and late parenchymal brain damage in patients with middle cerebral artery occlusion","volume":"20","author":"Bozzao","year":"1989","journal-title":"Stroke"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1002\/ana.21130","article-title":"Systematic comparison of perfusion-CT and CT-angiography in acute stroke patients","volume":"61","author":"Tan","year":"2007","journal-title":"Ann. Neurol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"643","DOI":"10.1148\/radiol.2017162445","article-title":"Absence of Cortical Vein Opacification Is Associated with Lack of Intra-arterial Therapy Benefit in Stroke","volume":"286","author":"Jansen","year":"2018","journal-title":"Radiology"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"288","DOI":"10.7461\/jcen.2023.E2022.11.005","article-title":"The impact of collateral status on cerebral vasospasm and delayed cerebral ischemia in subarachnoid hemorrhage","volume":"25","author":"Topcu","year":"2023","journal-title":"J. Cerebrovasc. Endovasc. Neurosurg."},{"key":"ref_42","first-page":"638","article-title":"Severity of cerebral vasospasm associated with development of collaterals following aneurysmal subarachnoid hemorrhage","volume":"10","author":"Witsch","year":"2018","journal-title":"J. Neurointerv. Surg."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"282","DOI":"10.3171\/2014.9.PEDS14313","article-title":"Extent of collateralization predicting symptomatic cerebral vasospasm among pediatric patients: Correlations among angiography, transcranial Doppler ultrasonography, and clinical findings","volume":"15","author":"Moftakhar","year":"2015","journal-title":"J. Neurosurg. Pediatr."},{"key":"ref_44","first-page":"1077","article-title":"Multisection Dynamic CT Perfusion for Acute Cerebral Ischemia: The \u201cToggling-table\u201d Technique","volume":"22","author":"Roberts","year":"2001","journal-title":"Am. J. Neuroradiol."},{"key":"ref_45","first-page":"720","article-title":"Dynamic perfusion CT: Optimizing the temporal resolution and contrast volume for calculation of perfusion CT parameters in stroke patients","volume":"25","author":"Wintermark","year":"2004","journal-title":"Am. J. Neuroradiol."}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/15\/17\/2236\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:38:43Z","timestamp":1760035123000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/15\/17\/2236"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,3]]},"references-count":45,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["diagnostics15172236"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics15172236","relation":{},"ISSN":["2075-4418"],"issn-type":[{"type":"electronic","value":"2075-4418"}],"subject":[],"published":{"date-parts":[[2025,9,3]]}}}