Dataset Information

Noninvasive In Vivo Thrombus Imaging in Patients With Ischemic Stroke or Transient Ischemic Attack-Brief Report.

ABSTRACT:

Background

¹⁸F-GP1 is a novel positron-emitting radiotracer that is highly specific for activated platelets and thrombus. In a proof-of-concept study, we aimed to determine its potential clinical application in establishing the role and origin of thrombus in ischemic stroke.

Methods

Eleven patients with recent ischemic stroke (n=9) or transient ischemic attack (n=2) underwent ¹⁸F-GP1 positron emission tomography and computed tomography angiography at a median of 11 (range, 2-21) days from symptom onset. ¹⁸F-GP1 uptake (maximum target-to-background ratio) was assessed in the carotid arteries and brain.

Results

¹⁸F-GP1 uptake was identified in 10 of 11 patients: 4 in the carotid arteries only, 3 in the brain only, and 3 in both the brain and carotid arteries. In those with carotid uptake, 4 participants had >50% stenosis and 3 had nonstenotic disease. One case had bilateral stenotic disease (>70%), but only the culprit carotid artery demonstrated ¹⁸F-GP1 uptake. The average uptake was higher in the culprit (median maximum target-to-background ratio, 1.55 [interquartile range, 1.26-1.82]) compared with the contralateral nonculprit carotid artery (maximum target-to-background ratio, 1.22 [1.19-1.6]). In those with brain ¹⁸F-GP1 uptake (maximum target-to-background ratio, 6.45 [4.89-7.65]), areas of acute infarction on computed tomography correlated with brain ¹⁸F-GP1 uptake in 6 cases. Ex vivo autoradiography of postmortem infarcted brain tissue showed focal uptake corresponding to intraluminal thrombus within the culprit vessel and downstream microvasculature. There was also evidence of diffuse uptake within some of the infarcted brain tissue reflecting parenchymal petechial hemorrhage.

Conclusions

¹⁸F-GP1 positron emission tomography and computed tomography angiography is a novel noninvasive method of identifying in vivo cerebrovascular thrombosis, which holds major promise in understanding the role and origin of thrombosis in stroke.

Registration

URL: https://www.

Clinicaltrials

gov; Unique identifier: NCT03943966.

SUBMITTER: Whittington B

PROVIDER: S-EPMC10443628 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

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Publications

Noninvasive In Vivo Thrombus Imaging in Patients With Ischemic Stroke or Transient Ischemic Attack-Brief Report.

Whittington Beth B Tzolos Evangelos E Bing Rong R Andrews Jack J Lucatelli Christophe C MacAskill Mark G MG Tavares Adriana A S AAS Clark Tim T Mills Nicholas L NL Nash Jennifer J Dey Damini D Slomka Piotr J PJ Koglin Norman N Stephens Andrew W AW van Beek Edwin J R EJR Smith Colin C Dweck Marc R MR Williams Michelle C MC Whiteley William W Wardlaw Joanna M JM Newby David E DE

Arteriosclerosis, thrombosis, and vascular biology 20230713 9

<h4>Background</h4><sup>18</sup>F-GP1 is a novel positron-emitting radiotracer that is highly specific for activated platelets and thrombus. In a proof-of-concept study, we aimed to determine its potential clinical application in establishing the role and origin of thrombus in ischemic stroke.<h4>Methods</h4>Eleven patients with recent ischemic stroke (n=9) or transient ischemic attack (n=2) underwent <sup>18</sup>F-GP1 positron emission tomography and computed tomography angiography at a median ...[more]

PMID: 37439259

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Dataset Information

Noninvasive In Vivo Thrombus Imaging in Patients With Ischemic Stroke or Transient Ischemic Attack-Brief Report.

Background

Methods

Results

Conclusions

Registration

Clinicaltrials

Publications

Noninvasive In Vivo Thrombus Imaging in Patients With Ischemic Stroke or Transient Ischemic Attack-Brief Report.

Similar Datasets

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