Correlations of amide proton transfer-weighted MRI of cerebral infarction with clinico-radiological findings

Abstract

Objective To clarify the relationship between amide proton transfer-weighted (APTW) signal, which reflects intracellular pH, and clinico-radiological findings in patients with hyperacute to subacute cerebral infarction. Materials and methods Twenty-nine patients (median age, 70 years [IQR, 54 to 74]; 15 men) were retrospectively examined. The 10th, 25th, 50th, 75th, and 90th percentiles of APTW signal (APT 10 , APT 25 , APT 50 , APT 75 and APT 90 , respectively) were measured within the infarction region-of-interest (ROI), and compared between poor prognosis and good prognosis groups (modified Rankin Scale [mRS] score �2 and mRS score <2, respectively). Correlations between APTW signal and time after onset, lesion size, National Institutes of Health Stroke Scale (NIHSS) score, mRS score, and mean apparent diffusion coefficient (ADC) were evaluated. Results The poor prognosis group had lower APT 50 , APT 75 , and APT 90 than the good prognosis group (

Clinical translation of amide proton transfer (APT) MRI for ischemic stroke: a systematic review (2003–2020)

“…Figure 3 shows representative APT images of ischemic stroke patients adapted from the included studies (26,29,30,33,40,43). Generally, the clinical studies shared the consensus that APT effect in ischemic tissue (inclusive of the ischemic core, penumbra, and benign oligemia) is smaller compared to normal healthy tissue in early stroke imaging.…”

“…The number of published clinical studies showed a gradual increase over the years. In the 14 studies, a total of 282 patients had been scanned with APT imaging after accounting for those judged to be duplicate analyses (using the same patient data but for different purposes); the study by Harston et al (33) and two studies by Msayib et al (34,35) (26,(33)(34)(35)(36)(37), three studies involved only acute stroke patients (29,38,39), one study included both hyperacute and acute patients (40), two studies involved acute and early subacute patients (41,42), while two studies involved patients from the hyperacute to early subacute stages (30,43). Further information on these studies such as the treatment received by patients, scanner field strength, radio frequency (RF) saturation scheme, imaging acquisition parameters, image acquisition time, APT effect quantification method, and other MRI sequences acquired, are presented in https://cdn.amegroups.cn/static/public/qims-20-1339-1.…”

“…Momosaka et al (43) later published a detailed investigation of the relationship between APT effect with clinico-radiological findings in ischemic stroke patients. It was discovered that APT effect was lower in the poor prognosis group compared to the good counterpart.…”

“…Six of the included studies involved only hyperacute patients, scanned within 24 hours from onset (26,(33)(34)(35)(36)(37), whereas the other eight studies involved patients that were scanned outside of this time frame (29,30,(38)(39)(40)(41)(42)(43). Among which, three studies investigated the progression of the disease with time, namely the studies by Song et al (40), Yu et al (30), and Momosaka et al (43). All three studies found APT signal within the ischemic lesion to gradually increase with increasing time from symptom onset.…”

“…In the studies by Song et al (40), Yu et al (30), and Momosaka et al (43), the authors attributed the increase in APT effect days after symptom onset to an increase of intracellular pH. However, these deductions may only be partially true since it is difficult to estimate the degree to which intracellular pH was acting as the main contributing factor to the increased APT effect.…”