Application of susceptibility-weighted imaging in intracranial dural arteriovenous fistula / 国际脑血管病杂志

Objective:To investigate the application value of susceptibility-weighted imaging (SWI) in the diagnosis of intracranial dural arteriovenous fistula (DAVF).Methods:Patients with DAVF confirmed by digital subtraction angiography (DSA) in Weihai Municipal Hospital from January 2014 to January 2021 were retrospectively included. All patients underwent conventional T 1-weighted imaging (T 1WI), T 2-weighted imaging (T 2WI) and SWI, and some patients also underwent 3D time-of-flight magnetic resonance angiography (3D-TOF-MRA). Results:A total of 36 patients with DAVF were enrolled, 29 of them received 3D-TOF-MRA. The fistula location of 24 patients (24/36, 66.7%) underwent SWI and 26 patients (26/29, 89.7%) underwent 3D-TOF-MRA were correctly judged, and the difference was statistically significant (Fisher's Exact Test, P=0.039). SWI showed that the proportion of patients with thickened supply arteries (7/36, 19.4%) was significantly lower than that on 3D-TOF-MRA (14/29, 48.3%; χ2=6.105, P=0.013). T 2WI, 3D-TOF-MRA and SWI showed no cerebral venous abnormalities in all 7 patients with DAVF without cortical venous reflux; in 29 patients with DAVF with cortical venous reflux revealed by DSA, SWI and T 2WI showed all patients (100%) and 26 patients (89.7%) had superficial venous dilatation respectively, but there was no significant difference ( χ2=0.693, P=0.405). SWI showed medullary vein dilation in 17 patients (47.2%), and only 2 patients (5.6%) had medullary vein thickening on T 2WI, and the difference was statistically significant ( P<0.001). The proportion of patients with venous cerebral infarction on T 2WI was significantly higher than that on SWI (22.2% vs. 0%; Fisher’s Exact Test P=0.005), and the proportion of patients with intracerebral hemorrhage on SWI was significantly higher than that on T 2WI (61.1% vs. 25.0%; χ2=9.574, P=0.004). Conclusion:SWI is helpful to evaluate the abnormal drainage vein of DAVF and the secondary changes in brain, especially intracerebral hemorrhage.

Combination of conventional axial and thin-layer sagittal diffusion-weighted imaging to improve the detection ability of acute brainstem infarction / 国际脑血管病杂志

Objective:To investigate whether the combination of conventional axial and thin-layer sagittal diffusion-weighted imaging (DWI) can improve the detection ability of acute brainstem infarction (ABI).Methods:Patients with ABI diagnosed clinically and admitted to Weihai Municipal Hospital, Shandong University from January 2019 to July 2020 were enrolled retrospectively. All patients underwent conventional axial and thin-layer sagittal DWI examination after admission. Those who could not make a definite diagnosis were confirmed by DWI reexamination before discharge. The numbers of positive and negative cases of brainstem infarction at different sites detected by conventional axial and conventional axial+ thin-layer sagittal DWI were recorded.Results:A total of 65 patients with ABI were included. Conventional axial DWI was positive in 51 patients (78.5%) and was negative in 14 (21.5%); conventional axial+ thin-layer sagittal DWI were positive in 60 patients (92.3%) and was negative in 5 (7.7%). In 8 patients with medullary infarction, only 4 (50.0%) were positive on conventional axial DWI, and 6 (75.0%) were positive on conventional axial+ thin-layer sagittal DWI; in 50 patients with pontine infarction, only 44 (88.0%) were positive on conventional axial DWI, and 48 (96.0%) were positive on conventional axial+ thin-layer sagittal DWI; in 4 patients with midbrain infarction, only 1 (25.0%) was positive on conventional axial DWI, and 3 (75.0%) were positive on conventional axial+ thin-layer sagittal DWI; in 3 patients with pontine+ midbrain infarction, only 2 (66.7%) were positive on conventional axial DWI, and 3 (100.0%) were positive on conventional axial DWI+ thin-layer sagittal DWI. The detection rate of ABI on conventional axial+ thin-layer sagittal DWI was significantly higher than that on conventional axial DWI, and difference was statistically significant (92.3% vs. 78.5%; χ2=4.993, P=0.026). Conclusion:The combination of conventional axial and thin-layer sagittal DWI improved the detection rate of ABI. For ABI patients whose axial DWI did not find lesions or whose diagnosis was not clear, thin-layer sagittal DWI should be added.

Development of Gun-type Tube-Guide Device of Laser Fiber / 中国医疗器械杂志

With the development of laryngeal microsurgery, the requirements for the flexibility and convenience of surgical instruments are increasing. The research on related instruments has important value for the clinical application of laryngeal microsurgery. We have redesigned a gun-type tube-guide device of laser fiber by comparing the shortcomings of existing laser fiber introducers. The innovation of this design lies in its rotating nut device with adjustable laser angle and pre-bent tip. The corresponding

Thrombopoietic stimulating activity of rhTyrRS (Y341A).

Tumor radiotherapy induces hematopoietic organ damage and reduces thrombocyte counts. Thrombocytopenia is a common disease. Some studies have shown that tRNA synthetase plays not only catalytic tRNA aminoacylation roles, but also functions similarly to cytokines. Recombinant human tyrosyl-tRNA synthetase with a mutated Y341A (rhTyrRS (Y341A)) promotes megakaryocyte migrate from bone marrow to peripheral blood. It would promote megakaryocytes in the lungs adhering to vascular endothelial cells and resulting in the platelet production. The purpose of this research was to investigate the efficacy of rhTyrRS (Y341A) as a therapy for thrombocytopenia and to explore its mechanism of action. We found platelet number was effectively increased by rhTyrRS (Y341A) via platelet count and reticulated platelets (RPs) flow cytometry. We also demonstrated radiation-induced thrombocytopenia could be prevented by rhTyrRS (Y341A). The results of immunohistochemistry and H&E staining showed the number of pulmonary mature megakaryocytes was significantly increased in rhTyrRS (Y341A) treated groups. In transgenic zebrafish larvae, confocal microscopy results showed rhTyrRS (Y341A) promoted the migration and adhesion of megakaryocytes. These results suggested that rhTyrRS (Y341A) promote megakaryocytes in bone marrow migrating to lungs through blood circulation. rhTyrRS (Y341A) may be an effective medicine which could be used to treat patients suffering from thrombocytopenia.

Diagnosing left ventricular noncompaction by cardiac MRI and its differential diagnosis on left ventricular hypertrabeculation / 中华放射学杂志

Objective To define the diagnostic criteria of cardiovascular magnetic resonance imaging in distinguishing isolated left ventricular noncompaction (LVNC) from lesser degrees of hypertrabeculation. Methods Twenty-five patients with LVNC, 39 with dilated cardiomyopathy ( DCM), 16 with aortic stenosis(AS), 15 with aortic regurgitation(AR) , 19 with hypertension (HT) and 22 normal subjects were enrolled in this study. Cardiac magnetic resonance imaging was performed to evaluate the left chamber diameter, functional parameters and noncompaction or hypertrabeculation of the left ventricle in diastole with one-way ANOVA. The left ventricle was divided into 17 segments for localizing all involved segments in this present study. Results The LVNC patients had the commonest myocardial segments involved (10±2)in all subjects. Each patient with LVNC was unexceptionally associated with apical noncompaction (17th segment) , which was seldom found in the other subjects. The lateral walls including 16th, 12th and 11th segments were the most vulnerable segments in all subjects, but nobody was found to involve the basal and mid septum including 2nd, 3rd, 8th and 9th segments. The end-diastolic NC/C (noncompaction/compaction) ratio was, on average, the greatest in patients with LVNC (3.3±0.6), compared with all other subjects(AS:1.0 ±0.3, AR:1.0 ±0.3,HT:0.8 ±0.1,healthy volunteers:0.9 ±0. 2) (F = 169. 62,P <0.05). Receiver operating characteristics analysis identified the end-diastolic NC/C ratio of>2.5 as a valuable parameter to distinguish LVNC from DCM.with values for sensitivity of 96.O%(24/25)and specificity of 94.9%(37/39),respectively.The mean number of NC/C ratio>2.5 segments in the LVNC patients was 4.0 ±2.0.while 8 of 39 patients with DCM had only one segment of NC/C ratio >2.5.Conclusions MRI is all exceUent imaging modality to diagnose LVNC and distinguish LIVNC from hypertrabeeulation.The criteria of LVNC is the NC/C ratio>2.5 in two or more than two segments of free ventricular walls associated with the left ventrieular apex involved.