Assessment of veins in T2*-weighted MR angiography predicts infarct growth in hyperacute ischemic stroke

SWI and CTP fusion model based on sparse representation method to predict cerebral infarction trend

Objective

SWI image signal is related to venous reflux disorder and perfusion defect. Computed tomography perfusion (CTP) contains perfusion information in space and time. There is a complementary basis between them to affect the prognosis of cerebral infarction.

Methods

Sixty-six patients included in the retrospective study were designated as the training set. Effective perfusion indicator features and imaging radiomic features of the peri-infarction area on Susceptibility weighted imaging (SWI) and CTP modality images were extracted from each case. Thirty-three patients from the prospectively included group were designated as the test set of the machine learning model based on a sparse representation method. The predicted results were compared with the DWI results of the patients' 7-10 days review to assess the validity and accuracy of the prediction.

Results

The AUC of the SWI + CTP integrated model was 0.952, the ACC was 0.909, the SEN was 0.889, and the SPE was 0.933. The prediction performance is the highest. Compared with the value of AUC: the SWI model is 0.874, inferior to the performance of the SWI + CTP model, and the CTP model is 0.715.

Conclusion

The prediction efficiency of the changing trend of infarction volume is further improved by the correlation between the combination of the two image features.

Application of Multimodal Magnetic Resonance Imaging in Green Channel of Acute and Hyperacute Ischemic Stroke

The purpose of this study was to observe the effects of multimodal magnetic resonance imaging (MRI) in the green channel of acute and hyperacute ischemic strokes, in order to better guide clinical treatment. The clinical data of 126 patients with acute and hyperacute ischemic stroke who received interventional treatment in the emergency green channel was collected retrospectively. The patients who received multimodal computed tomography (CT) were included in the CT group. Patients who underwent multimodal MRI examinations were included in the MRI group, and the door-to-needle time (DNT), neurological function, and prognosis of the two groups were compared. The result turned out that among the 126 patients included, 40 patients underwent CT examination (CT group) and 86 patients underwent MRI examination (MRI group). A comparison of general data between the CT group and the MRI group showed $P>0.05$ . The MRI group’s DNT time (61.23 ± 9.32) min was shorter than that of the CT group (87.22 ± 14.26) min, $P<0.05$ . Through comparison, the $P$ values of mRS scores and NIHSS scores in both groups were greater than 0.05. After treatment, the mRS score and NIHSS score of the MRI group was lower, with $P<0.05$ . According to the results of this study, it can be concluded that emergency multimodal MRI could shorten the DNT time of patients with acute and hyperacute ischemic stroke, reduce the degree of neurological impairment, and improve the prognosis.

Hypointensity of draining veins on susceptibility-weighted magnetic resonance images might indicate normal venous flow and a lower risk of intracerebral hemorrhage in patients with intracranial arteriovenous shunt(s)

Patients with intracranial arteriovenous shunt(s) have a risk of intracerebral hemorrhage (ICH). We investigated the signal intensity of draining veins on susceptibility-weighted imaging (SWI) and the status of venous drainage shown by digital subtraction angiography (DSA). We then evaluated whether the signal intensity of draining veins on SWI is related to normal venous flow (NVF) and/or ICH. We analyzed SWI and DSA in 10 consecutive patients with intracranial arteriovenous shunt(s). Opacification of draining veins in the normal venous phase by DSA was judged as NVF. We evaluated the relationship between the intensity of draining veins on SWI and the presence of NVF before and after treatment. The relationship between the intensity of draining veins on SWI and the presence of ICH surrounding the draining veins was also evaluated. Of 10 patients with untreated arteriovenous shunt(s), two had arteriovenous malformation and eight had a dural arteriovenous fistula with cortical venous reflux. We analyzed 26 draining veins before treatment. In preoperative analysis, draining veins with hypointensity were significantly more likely to show NVF than were draining veins with isointensity or hyperintensity (45.5% vs. 0.0%, P = 0.007). While 69.2% of the areas surrounding draining veins with isointensity or hyperintensity showed ICH, no veins with hypointensity showed ICH (P = 0.011, odds ratio 0.036; 95% confidence interval 0.0017-0.80). In conclusion, draining veins with hypointensity on SWI may contain NVF, despite arteriovenous shunting. The areas surrounding these veins might have a lower risk of ICH because of less venous hypertension.