Atypical MRI Manifestation of Contrast-Induced Encephalopathy Following Cerebral Angiography

Atypical MRI Manifestation of Contrast-Induced Encephalopathy Following Cerebral Angiography | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Atypical MRI Manifestation of Contrast-Induced Encephalopathy Following Cerebral Angiography Hui CHENG, Lijiang CHEN, Yi MAO, Zhicai CHEN, Yue PAN This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6973612/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Background Contrast-induced encephalopathy (CIE) is a rare complication associated with the intravascular administration of contrast agents, particularly following neurointerventions. Conventional imaging findings typically include cortical or subcortical contrast enhancement on computed tomography (CT) and vasogenic edema on magnetic resonance imaging (MRI). This case highlights the atypical MRI findings of CIE distinct from those previously reported and emphasizes the importance of early diagnosis and management. Case Presentation A 69-year-old woman developed acute neurological symptoms following a selective cerebral angiography. MRI revealed multiple, scattered lesions that were hyperintense on diffusion-weighted imaging (DWI) and hypointense on the apparent diffusion coefficient (ADC) map, findings consistent with cytotoxic edema. After a diagnosis of CIE was made, the patient received symptomatic treatment, she recovered rapidly and completely after receiving supportive treatment. Follow-up imaging confirmed the full resolution of all lesions. Conclusion This atypical MRI manifestation broadens the understanding of the radiological spectrum of CIE. Contrast-Induced Encephalopathy Cerebral Angiography Diffusion Magnetic Resonance Imaging Ischemic Stroke Figures Figure 1 Figure 2 Background Contrast-induced encephalopathy (CIE) is a rare complication associated with the intravascular administration of contrast agents, particularly following neurointerventions. The reported incidence of CIE in this setting ranges from 0.3–1.0%. Clinically, patients can present with a spectrum of acute neurological symptoms, including cortical blindness, headache, seizures, focal deficits, and disturbances of consciousness. According to previous reports, the widely accepted radiological features are subarachnoid contrast leakage on computed tomography (CT) and cortical/subcortical vasogenic edema on magnetic resonance imaging (MRI)[ 1 ]. This case report describes an atypical presentation of CIE. By presenting this case, we aim to broaden the understanding of the radiological manifestations of CIE and emphasize the importance of its prompt diagnosis. Case Presentation A 69-year-old female with right-sided hemiparesis was diagnosed with acute ischemic stroke in the left basal ganglia region twenty days earlier at a local hospital, caused by occlusion of the left middle cerebral artery (MCA). Neurological examination was unremarkable, with a National Institutes of Health Stroke Scale (NIHSS) score of 0 at admission. Magnetic Resonance Angiography (MRA) combined with Diffusion-Weighted Imaging (DWI) at our hospital identified a subacute infarction in the left basal ganglia and an occlusion in the M1 segment of the left MCA. Digital subtraction angiography confirmed left MCA occlusion. The patient received 32 ml of ioversol for additional 3D imaging of the right carotid artery and 16 ml for the left side. The procedure was uneventful. Two hours later, the patient developed restlessness, headache, and vomiting, accompanied by fever, hypertension, and tachycardia. Symptoms persisted despite prompt symptomatic treatment. By 12 hours, she became drowsy, with left hemiplegia, increased limb muscle tone, and suspected neck stiffness (NIHSS score: 11). Emergency blood tests and cardiac evaluations were normal, excluding metabolic, cardiac, and hepatic causes of acute consciousness disturbance. Urgent CT showed no high-density lesions, and Magnetic Resonance Angiography (MRA) showed no new vascular occlusions. Diffusion-Weighted Imaging (DWI) revealed scattered diffusion-restricted lesions, hyperintense on DWI with reduced apparent diffusion coefficient (ADC), in the cortical and subcortical regions across multiple lobes in the right hemisphere (Fig. 1 ). T2-weighted fluid-attenuated inversion recovery(FLAIR) imaging demonstrated extensive swelling exceeding DWI findings, with sulcal obliteration and gyral widening (Fig. 2 ). That evening, the patient lapsed into a shallow coma and experienced two prolonged seizures. She was diagnosed with CIE and was managed immediately with aggressive fluid resuscitation, intracranial pressure reduction, anticonvulsants, and antiplatelet therapy. By the following morning, the patient's consciousness improved. Approximately 60 hours after symptom onset, her mental clarity and muscle strength recovered, and vital signs normalized. Follow-up MRI showed a marked lesion reduction in extent and intensity, and she was discharged two days after recovery. At one-month follow-up, the patient reported no symptoms. Neurological examination showed a modified Rankin Scale (mRS) score of 1 and NIHSS score of 0. A repeat MRI showed complete resolution of CIE lesions and swelling. Interestingly, the original ischemic stroke lesion persisted as a comparison. Discussion and Conclusions Previous studies have highlighted vasogenic edema with DWI hyperintensity and isointense ADC as typical MRI findings in CIE[ 1 ]. However, our case demonstrates that CIE may also present with cytotoxic edema and diffusion-restricted lesions characterized by DWI hyperintensity and ADC hypointensity. CIE is a diagnosis of exclusion, with ischemic stroke being the most common differential. In this case, the patient’s clinical and imaging findings raised suspicion of a new acute ischemic stroke. However, the left MCA occlusion would more likely localize a new infarct to the left hemisphere, while lesions appeared on the right. Interestingly, the old infarct served as a control, as new lesions resolved more rapidly, reflecting distinct pathology. The patient’s sudden rise in blood pressure prompted consideration of posterior reversible encephalopathy syndrome (PRES), but unilateral, cortical lesions confined to the anterior circulation ruled it out. Considering the temporal link to the procedure, unique imaging, and rapid recovery, CIE was diagnosed. Although the exact pathophysiology of CIE remains unclear, disruption of the blood-brain barrier (BBB), leading to contrast leakage and neurotoxicity, is the widely accepted mechanism[ 2 ]. This is supported by studies detecting high iodinated contrast in cerebrospinal fluid (CSF)[ 3 ]. Another possible mechanism is diffuse vasospasm triggered by contrast injection, with cases confirmed through arterial spin labeling (ASL) MRI[ 4 ]. The greater sensitivity of small arteries to vasospasms may also explain the scattered superficial subcortical distribution of the T2-FLAIR lesions. CIE typically resolves quickly with favorable outcomes, though rare cases of permanent deficits occur[ 5 ]. Early recognition and management are essential. Diagnostic tools include CT, MRI, and CSF analysis. Treatments include aggressive hydration, intracranial pressure reduction, corticosteroids for anti-inflammatory effects, and early diuretic therapy for patients with renal insufficiency[ 6 ]. As a rare but heterogeneous acute complication with generally favorable outcomes, CIE should always be considered in patients presenting with neurological deterioration following neurointerventional procedures. CIE may present with DWI hyperintensity and ADC hypointensity, and these findings should not be misinterpreted as ischemic stroke. Abbreviations CIE Contrast-induced encephalopathy CT Computed Tomography MRI Magnetic Resonance Imaging DWI Diffusion-Weighted Imaging ADC Apparent Diffusion Coefficient MCA Middle Cerebral Artery NIHSS National Institutes of Health Stroke Scale MRA Magnetic Resonance Angiography FLAIR Fluid-Attenuated Inversion Recovery mRS Modified Rankin Scale PRES Posterior Reversible Encephalopathy Syndrome BBB Blood-Brain Barrier CSF Cerebrospinal Fluid ASL Arterial Spin Labeling Declarations Ethics approval and consent to participate Ethics approval : approved by Ethics Committee of The Second Affiliated Hospital of Zhejiang University, School of Medicine. Reference number: YAN2025-0639. Consent for publication Written consent obtained from the patient for publication purpose. Detail of the patient has been anonymized. Competing interests The authors declare that they have no competing interests. Funding This work was supported by Medical Health Science and Technology Project of Zhejiang Provincial Health Commission (2025KY835). Author Contribution YP and LC made substantial contributions to the conception of the work. YP drafted the original manuscript. ZC, YM, and HC substantively revised the work. ZC and HC provided supervision. All authors read and approved the final manuscript. All authors had access to the data. Acknowledgements: not applicable. Availability of data and materials: not applicable. References Zevallos CB, Dandapat S, Ansari S, Farooqui M, Quispe-Orozco D, Mendez-Ruiz A, et al. Clinical and Imaging Features of Contrast-Induced Neurotoxicity After Neurointerventional Surgery. World Neurosurg. 2020;142:e316–24. Maclean MA, Rogers PS, Muradov JH, Pickett GE, Friedman A, Weeks A et al. Contrast-Induced Encephalopathy and the Blood-Brain Barrier. Can J Neurol Sci. 2024;:1–10. Uchiyama Y, Abe T, Hirohata M, Tanaka N, Kojima K, Nishimura H, et al. Blood Brain–Barrier Disruption of Nonionic Iodinated Contrast Medium Following Coil Embolization of a Ruptured Intracerebral Aneurysm. Am J Neuroradiol. 2004;25:1783–6. Romano DG, Frauenfelder G, Locatelli G, Panza MP, Siani A, Tartaglione S, et al. Arterial Spin Labeling Magnetic Resonance Imaging to Diagnose Contrast-Induced Vasospasm After Intracranial Stent Embolization. World Neurosurg. 2019;126:341–5. Zhao W, Zhang J, Song Y, Sun L, Zheng M, Yin H, et al. Irreversible fatal contrast-induced encephalopathy: a case report. BMC Neurol. 2019;19:46. Matsubara N, Izumi T, Miyachi S, Ota K, Wakabayashi T. Contrast-induced Encephalopathy Following Embolization of Intracranial Aneurysms in Hemodialysis Patients. Neurol Med Chir(Tokyo). 2017;57:641–8. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editor invited by journal 26 Jun, 2025 Editor assigned by journal 26 Jun, 2025 Submission checks completed at journal 26 Jun, 2025 First submitted to journal 25 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6973612","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":476533344,"identity":"3b2fbbf1-0ba4-4ae7-8725-c27f21752580","order_by":0,"name":"Hui CHENG","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital","correspondingAuthor":false,"prefix":"","firstName":"Hui","middleName":"","lastName":"CHENG","suffix":""},{"id":476533345,"identity":"207f36a5-1f54-46f3-96e1-29a631abb021","order_by":1,"name":"Lijiang CHEN","email":"","orcid":"","institution":"Shaoxing city Keqiao District Hospital of traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Lijiang","middleName":"","lastName":"CHEN","suffix":""},{"id":476533360,"identity":"8ea00484-de75-45c9-96ee-ce3deeb7ef79","order_by":2,"name":"Yi MAO","email":"","orcid":"","institution":"Zhejiang University School of Medicine, The First People’s Hospital of Jiande","correspondingAuthor":false,"prefix":"","firstName":"Yi","middleName":"","lastName":"MAO","suffix":""},{"id":476533365,"identity":"e3d57024-56c8-4d65-9956-0243ac926978","order_by":3,"name":"Zhicai CHEN","email":"","orcid":"","institution":"The Second Affiliated Hospital of Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Zhicai","middleName":"","lastName":"CHEN","suffix":""},{"id":476533366,"identity":"6e152378-5bd6-4ee3-ad75-cc9e4700998d","order_by":4,"name":"Yue PAN","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6UlEQVRIie3RsUoDQRCA4TkW9pqRazegeYaFa4QE8iozCEkTrC0sFoSkCaQ9nyOQepaDVBts09lpe08QXVNZrWsnuH83MB/MsgCl0h+sqdciA35gA0BxVj+T0Saw767VeORyiT1R2+NUtVYucwYBIfLdUvPuRd4MPEzY1UdJisr5+JaAvBeZGwgLdnhPSaIqR/55Y3jv3dxUq56dQZskWoHtr86Wd08QyTmDoI4EkVqrv4jLICau+w5lbALc3dJh0a5wmSaz1/d+GFCw2QY+DY+Tm20d0uT7jXT5TJ27H6vlF8ulUqn0n/oE665KFN20el8AAAAASUVORK5CYII=","orcid":"","institution":"The Second Affiliated Hospital of Zhejiang University","correspondingAuthor":true,"prefix":"","firstName":"Yue","middleName":"","lastName":"PAN","suffix":""}],"badges":[],"createdAt":"2025-06-25 10:38:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6973612/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6973612/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":85618763,"identity":"8c782629-8d4f-4756-b803-a212385f487b","added_by":"auto","created_at":"2025-06-29 14:51:53","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":2464851,"visible":true,"origin":"","legend":"\u003cp\u003eDiffusion MRI\u003c/p\u003e\n\u003cp\u003eOne day post-surgery, MRI revealed multiple diffusion-restricted lesions, hyperintense on DWI with reduced ADC, located in the cortical and subcortical regions of several lobes. A follow-up MRI conducted 5 days after symptom onset showed a marked reduction in the extent and intensity of the previously identified lesions. A repeat MRI showed complete resolution of those lesions. The last row shows old lesions for comparison. The arrows point to the newly developed lesions, and the asterisks indicate the old ischemic infarction lesions.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-6973612/v1/adc913fed95b0761ff9ebf69.png"},{"id":85618761,"identity":"eacae5b0-8263-46c6-af3d-aba0243837af","added_by":"auto","created_at":"2025-06-29 14:51:53","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":2226012,"visible":true,"origin":"","legend":"\u003cp\u003eFLAIR MRI\u003c/p\u003e\n\u003cp\u003eOne day after symptom onset, FLAIR imaging revealed extensive swelling in the right hemisphere, predominantly involving the temporal and occipital lobes. This was characterized by sulcal obliteration, gyral widening, and widespread high signal intensity in both cortical and subcortical regions. The swelling extended beyond the areas of diffusion-restricted lesions observed on DWI. At the one-month follow-up, repeat MRI revealed complete resolution of the previously noted diffusion-restricted lesions and brain swelling. Panel A illustrates DWI sequence images, while Panels B and C illustrate FLAIR sequence images.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-6973612/v1/1b5227a9c5b3ca333a9ae45c.png"},{"id":85619991,"identity":"1297d290-2c5b-4f2b-8b2d-c2c28f074adb","added_by":"auto","created_at":"2025-06-29 15:07:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6289450,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6973612/v1/26194174-d3d5-4044-86a3-8e27b7fa5bfb.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Atypical MRI Manifestation of Contrast-Induced Encephalopathy Following Cerebral Angiography","fulltext":[{"header":"Background","content":"\u003cp\u003eContrast-induced encephalopathy (CIE) is a rare complication associated with the intravascular administration of contrast agents, particularly following neurointerventions. The reported incidence of CIE in this setting ranges from 0.3\u0026ndash;1.0%. Clinically, patients can present with a spectrum of acute neurological symptoms, including cortical blindness, headache, seizures, focal deficits, and disturbances of consciousness. According to previous reports, the widely accepted radiological features are subarachnoid contrast leakage on computed tomography (CT) and cortical/subcortical vasogenic edema on magnetic resonance imaging (MRI)[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. This case report describes an atypical presentation of CIE. By presenting this case, we aim to broaden the understanding of the radiological manifestations of CIE and emphasize the importance of its prompt diagnosis.\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eA 69-year-old female with right-sided hemiparesis was diagnosed with acute ischemic stroke in the left basal ganglia region twenty days earlier at a local hospital, caused by occlusion of the left middle cerebral artery (MCA). Neurological examination was unremarkable, with a National Institutes of Health Stroke Scale (NIHSS) score of 0 at admission. Magnetic Resonance Angiography (MRA) combined with Diffusion-Weighted Imaging (DWI) at our hospital identified a subacute infarction in the left basal ganglia and an occlusion in the M1 segment of the left MCA. Digital subtraction angiography confirmed left MCA occlusion. The patient received 32 ml of ioversol for additional 3D imaging of the right carotid artery and 16 ml for the left side. The procedure was uneventful.\u003c/p\u003e \u003cp\u003eTwo hours later, the patient developed restlessness, headache, and vomiting, accompanied by fever, hypertension, and tachycardia. Symptoms persisted despite prompt symptomatic treatment. By 12 hours, she became drowsy, with left hemiplegia, increased limb muscle tone, and suspected neck stiffness (NIHSS score: 11). Emergency blood tests and cardiac evaluations were normal, excluding metabolic, cardiac, and hepatic causes of acute consciousness disturbance.\u003c/p\u003e \u003cp\u003eUrgent CT showed no high-density lesions, and Magnetic Resonance Angiography (MRA) showed no new vascular occlusions. Diffusion-Weighted Imaging (DWI) revealed scattered diffusion-restricted lesions, hyperintense on DWI with reduced apparent diffusion coefficient (ADC), in the cortical and subcortical regions across multiple lobes in the right hemisphere (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). T2-weighted fluid-attenuated inversion recovery(FLAIR) imaging demonstrated extensive swelling exceeding DWI findings, with sulcal obliteration and gyral widening (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). That evening, the patient lapsed into a shallow coma and experienced two prolonged seizures. She was diagnosed with CIE and was managed immediately with aggressive fluid resuscitation, intracranial pressure reduction, anticonvulsants, and antiplatelet therapy.\u003c/p\u003e\u003cp\u003eBy the following morning, the patient's consciousness improved. Approximately 60 hours after symptom onset, her mental clarity and muscle strength recovered, and vital signs normalized. Follow-up MRI showed a marked lesion reduction in extent and intensity, and she was discharged two days after recovery. At one-month follow-up, the patient reported no symptoms. Neurological examination showed a modified Rankin Scale (mRS) score of 1 and NIHSS score of 0. A repeat MRI showed complete resolution of CIE lesions and swelling. Interestingly, the original ischemic stroke lesion persisted as a comparison.\u003c/p\u003e "},{"header":"Discussion and Conclusions","content":"\u003cp\u003ePrevious studies have highlighted vasogenic edema with DWI hyperintensity and isointense ADC as typical MRI findings in CIE[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. However, our case demonstrates that CIE may also present with cytotoxic edema and diffusion-restricted lesions characterized by DWI hyperintensity and ADC hypointensity.\u003c/p\u003e\u003cp\u003eCIE is a diagnosis of exclusion, with ischemic stroke being the most common differential. In this case, the patient’s clinical and imaging findings raised suspicion of a new acute ischemic stroke. However, the left MCA occlusion would more likely localize a new infarct to the left hemisphere, while lesions appeared on the right. Interestingly, the old infarct served as a control, as new lesions resolved more rapidly, reflecting distinct pathology.\u003c/p\u003e\u003cp\u003eThe patient’s sudden rise in blood pressure prompted consideration of posterior reversible encephalopathy syndrome (PRES), but unilateral, cortical lesions confined to the anterior circulation ruled it out. Considering the temporal link to the procedure, unique imaging, and rapid recovery, CIE was diagnosed.\u003c/p\u003e\u003cp\u003eAlthough the exact pathophysiology of CIE remains unclear, disruption of the blood-brain barrier (BBB), leading to contrast leakage and neurotoxicity, is the widely accepted mechanism[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. This is supported by studies detecting high iodinated contrast in cerebrospinal fluid (CSF)[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Another possible mechanism is diffuse vasospasm triggered by contrast injection, with cases confirmed through arterial spin labeling (ASL) MRI[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. The greater sensitivity of small arteries to vasospasms may also explain the scattered superficial subcortical distribution of the T2-FLAIR lesions.\u003c/p\u003e\u003cp\u003eCIE typically resolves quickly with favorable outcomes, though rare cases of permanent deficits occur[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Early recognition and management are essential. Diagnostic tools include CT, MRI, and CSF analysis. Treatments include aggressive hydration, intracranial pressure reduction, corticosteroids for anti-inflammatory effects, and early diuretic therapy for patients with renal insufficiency[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAs a rare but heterogeneous acute complication with generally favorable outcomes, CIE should always be considered in patients presenting with neurological deterioration following neurointerventional procedures. CIE may present with DWI hyperintensity and ADC hypointensity, and these findings should not be misinterpreted as ischemic stroke.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCIE\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eContrast-induced encephalopathy\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eComputed Tomography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMagnetic Resonance Imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eDWI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eDiffusion-Weighted Imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eADC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eApparent Diffusion Coefficient\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMCA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMiddle Cerebral Artery\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eNIHSS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eNational Institutes of Health Stroke Scale\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMagnetic Resonance Angiography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eFLAIR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eFluid-Attenuated Inversion Recovery\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003emRS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eModified Rankin Scale\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePRES\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePosterior Reversible Encephalopathy Syndrome\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eBBB\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eBlood-Brain Barrier\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCSF\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eCerebrospinal Fluid\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eASL\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eArterial Spin Labeling\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e: approved by Ethics Committee of The Second Affiliated Hospital of Zhejiang University, School of Medicine. Reference number: YAN2025-0639.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten consent obtained from the patient for publication purpose. Detail of the patient has been anonymized.\u003c/p\u003e\n\u003ch2\u003eCompeting interests\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eThis work was supported by Medical Health Science and Technology Project of Zhejiang Provincial Health Commission (2025KY835).\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eYP and LC made substantial contributions to the conception of the work. YP drafted the original manuscript. ZC, YM, and HC substantively revised the work. ZC and HC provided supervision. All authors read and approved the final manuscript. All authors had access to the data.\u003c/p\u003e\n\u003ch2\u003eAcknowledgements:\u003c/h2\u003e\n\u003cp\u003enot applicable.\u003c/p\u003e\n\u003ch2\u003eAvailability of data and materials:\u003c/h2\u003e\n\u003cp\u003enot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eZevallos CB, Dandapat S, Ansari S, Farooqui M, Quispe-Orozco D, Mendez-Ruiz A, et al. Clinical and Imaging Features of Contrast-Induced Neurotoxicity After Neurointerventional Surgery. World Neurosurg. 2020;142:e316\u0026ndash;24.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaclean MA, Rogers PS, Muradov JH, Pickett GE, Friedman A, Weeks A et al. Contrast-Induced Encephalopathy and the Blood-Brain Barrier. Can J Neurol Sci. 2024;:1\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUchiyama Y, Abe T, Hirohata M, Tanaka N, Kojima K, Nishimura H, et al. Blood Brain\u0026ndash;Barrier Disruption of Nonionic Iodinated Contrast Medium Following Coil Embolization of a Ruptured Intracerebral Aneurysm. Am J Neuroradiol. 2004;25:1783\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRomano DG, Frauenfelder G, Locatelli G, Panza MP, Siani A, Tartaglione S, et al. Arterial Spin Labeling Magnetic Resonance Imaging to Diagnose Contrast-Induced Vasospasm After Intracranial Stent Embolization. World Neurosurg. 2019;126:341\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhao W, Zhang J, Song Y, Sun L, Zheng M, Yin H, et al. Irreversible fatal contrast-induced encephalopathy: a case report. BMC Neurol. 2019;19:46.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMatsubara N, Izumi T, Miyachi S, Ota K, Wakabayashi T. Contrast-induced Encephalopathy Following Embolization of Intracranial Aneurysms in Hemodialysis Patients. Neurol Med Chir(Tokyo). 2017;57:641\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-neurology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"nurl","sideBox":"Learn more about [BMC Neurology](http://bmcneurol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/nurl","title":"BMC Neurology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Contrast-Induced Encephalopathy, Cerebral Angiography, Diffusion Magnetic Resonance Imaging, Ischemic Stroke","lastPublishedDoi":"10.21203/rs.3.rs-6973612/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6973612/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eContrast-induced encephalopathy (CIE) is a rare complication associated with the intravascular administration of contrast agents, particularly following neurointerventions. Conventional imaging findings typically include cortical or subcortical contrast enhancement on computed tomography (CT) and vasogenic edema on magnetic resonance imaging (MRI). This case highlights the atypical MRI findings of CIE distinct from those previously reported and emphasizes the importance of early diagnosis and management.\u003c/p\u003e\u003ch2\u003eCase Presentation\u003c/h2\u003e \u003cp\u003eA 69-year-old woman developed acute neurological symptoms following a selective cerebral angiography. MRI revealed multiple, scattered lesions that were hyperintense on diffusion-weighted imaging (DWI) and hypointense on the apparent diffusion coefficient (ADC) map, findings consistent with cytotoxic edema. After a diagnosis of CIE was made, the patient received symptomatic treatment, she recovered rapidly and completely after receiving supportive treatment. Follow-up imaging confirmed the full resolution of all lesions.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis atypical MRI manifestation broadens the understanding of the radiological spectrum of CIE.\u003c/p\u003e","manuscriptTitle":"Atypical MRI Manifestation of Contrast-Induced Encephalopathy Following Cerebral Angiography","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-29 14:51:49","doi":"10.21203/rs.3.rs-6973612/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvited","content":"","date":"2025-06-26T19:57:05+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-26T04:49:25+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-06-26T04:46:16+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Neurology","date":"2025-06-25T10:24:24+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-neurology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"nurl","sideBox":"Learn more about [BMC Neurology](http://bmcneurol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/nurl","title":"BMC Neurology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"feaaffdf-8250-484d-9c2c-04b675130470","owner":[],"postedDate":"June 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-07-21T06:38:33+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-29 14:51:49","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6973612","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6973612","identity":"rs-6973612","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}