Objective To evaluate the apparent diffusion coefficient(ADC) value of mono-exponential diffusion weighted imaging(DWI) and the true diffusion coefficient(D) value, related diffusion coefficient(D*) value, perfusion fraction (f) value of bi-exponential model DWI in reflecting the expression of vascular endothelial growth factor (VEGF).Methods Using immunohistochemical staining method to detect VEGF expression in the 28 cases of gastric carcinoma tissue section and the surrounding normal gastric tissue.The differences of ADC value, D value, D* value, f value in different VEGF expression grading and gastric carcinoma classification were analyzed respectively.Results The differences of ADC value, D value, f value between different VEGF grading were statically significant,as the higher VEGF grading accompanied wth the lower ADC values, D value and the higher of f value;and the differences of the parameters between high and low differentiated gastric carcinoma were also statically significant (P<0.05).Conclusion The ADC value of mono-exponential DWI and the D value,f value of bi-exponential model DWI could evaluate the expression of VEGF and reflect the gastric carcinoma angiogenesis.

Objective To investigate the clinical characteristics and emergency management of severe hand-foot-mouth disease(HFMD)associated with encephalitis and neurogenic pulmonary edema(NPE)caused by en-terovirus 71(EV71)in children.Method Data of critical patients with severe HFMD associated with encephalitis and NPE admitted to pediatric intensive care unit(PICU)Fuyan city Hospitals Anhni Province from May to June 2008 were reviewed.Results Of 30 patients,the mean age was 15.8 months ranged from 4 months to 48 months.The overall morality was 19.4%.Tha average duration of critical symptoms persisted Was 2.1 days ranged from 12 hours to 5 days.There were no rash found in 12 patients(33.3%).The chinical features of nervous system mani-fested the symptoms of brainstem encephalitis in 27 patients(75%),brainstem encephalitis with myelitis in 6 pa-tients(16.7%),and encephalitis in 3 patients(8.3%).The frothy expectoration tinged with pink or bloody,asyrmmetrical pulmonary edema or hemoptysis were the main features of NPE.The main approaches to the treatment were mechanical ventilation,mannitol,methylpredifiselone,intravenous immunoglobulin(IVIG),and vasoactive a-gents.And nine patients(25%)needed fluid volume resuscitation in addition.Conclusions Young children are particularly vulnerable to the Severe EV71 encephalitis with NPE.The majority of involved fatal patients are aged under 3 years.Patients may die of acute onset of NPE and/or hemoptysis with rapid progress towards cardiopul-monary failure.Early diagnosis and evaluation,respiratory support,lowering intracranial pressure and maintaining hemodynamics ale the essential therapeutic approaches.

Objective:To summarize the imaging features of severe unilateral transverse sinus and sigmoid sinus thromboses, and evaluate the efficacy and safety of intravascular interventional therapy in them.Methods:Thirty-seven patients with severe unilateral transverse sinus and sigmoid sinus thromboses clinically mainly manifested as intracranial hypertension and accepted endovascular intervention in Department of Interventional Radiology, First Affiliated Hospital of Zhengzhou University from June 2012 to September 2022 were chosen; their clinical data were retrospectively analyzed and imaging features were summarized. Short-term efficacy was evaluated according to blood flow restoration degrees and pressure gradient reduction in the occlusive sinus and modified neurological symptoms before and after endovascular intervention. Hospitalized complications were observed; safety and long-term efficacy were evaluated according to postoperative clinical follow-up and imaging results 6-12 months after endovascular intervention.Results:(1) Preoperative brain MRI and (or) CT showed different degrees of swelling of the brain tissues, with the affected side as the target; mixed signals/density shadow could be seen in the blocked transverse sinus and sigmoid sinus; venous cerebral infarction or post-infarction cerebral hemorrhage could be combined in some patients. MRV, CTV and DSA showed poor or completely occluded transverse sinus and sigmoid sinus while normal in the contralateral side; obvious thrombus filling-defect was observed in the occluded venous sinus after mechanical thrombolysis. (2) Occlusive sinus blood flow was restored in all patients after endovascular intervention, and pressure gradient of the occlusive segment decreased from (16.6±3.3) mmHg before to (2.8±0.8) mmHg after endovascular intervention. Before discharge, clinical symptoms of all patients were significantly improved (modified Rankin scale [mRS] scores of 0 in 30 patients, 1 in 5 patients, 2 in 1 patient and 3 in 1 patient), and 2 patients had unilateral limb movement disorder (muscle strength grading III and IV, respectively). All patients received clinical follow-up for (9.6±3.0) months. At the last follow-up, neurological function obviously improved compared with that before endovascular intervention, without new neurosystem-related symptoms (mRS scores of 0 in 30 patients, 1 in 6, and 2 in 1 patient). In 34 patients received MRV or DSA follow-up, 28 had complete recanalization of occlusive sinus and 6 had partial recanalization, without obvious stenosis or recurrent occlusion.Conclusions:Severe unilateral transverse sinus and sigmoid sinus thrombosis can cause local intracranial venous blood stasis, and then cause "increased regional venous sinus pressure", which is manifested as unilateral brain tissue swelling and even venous cerebral infarction or post-infarction cerebral hemorrhage. Early diagnosis and endovascular intervention can obviously improve the prognosis of these patients, enjoying good safety.

Objective:To investigate the application value of optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in evaluating flow diverter (FD) apposition and endothelialization in aneurysm animal models, and analyze the effect of incomplete stent apposition (ISA) on aneurysm lumen healing and stent endothelialization.Methods:Lateral common carotid artery aneurysm models in swines were established by surgical method and then FD was implanted. Immediately after surgery, OCT and IVUS were used to evaluate the locations and degrees of ISA, and difference between these 2 methods in evaluating FD apposition was compared. DSA was performed at 12 weeks after surgery to evaluate the aneurysm occlusion (Kamran grading) and stent patency. OCT and IVUS were used again to observe the stent endothelial situation; by comparing with histopathologic results, effect of ISA on aneurysm healing and stent endothelialization was analyzed.Results:Lateral common carotid artery aneurysm models in 6 swines were established, and 6 Tubridge FDs were successfully implanted. Compared with IVUS (3 stents, 4 locus), OCT could detect more ISA (6 stents, 14 locus); and the vascular diameter change area (7 locus), aneurysm neck area (4 locus) and the head and tail of FD (3 locus) were the main sites of FD malapposition; average distance between stent wire and vessel wall was (560.14±101.48) μm. At 12 weeks after surgery, DSA showed that 1 patient had a little residual contrast agent at the aneurysm neck (Kamran grading 3), and the remaining 5 had complete aneurysm occlusion (Kamran grading 4). One FD had moderate lumen stenosis, and the other 5 FDs had lumen patency. OCT indicated mostly disappeared acute ISA; ISA proportion decreased to 21.4 % (3/14), including 2 in the aneurysm neck and 1 in the partial stent. Histopathological results showed bare stent woven silk, without obvious endothelial coverage; in one FD with luminal stenosis, intimal hyperplasia was mainly composed of vascular smooth muscle cells.Conclusion:In carotid artery aneurysm model with FD implantation, OCT can detect more ISA than IVUS; most acute ISA have good outcome at 12 th week of follow-up, while severe ISA can cause delayed FD endothelialization and delayed aneurysm occlusion.

Objective:To establish the carotid artery in-stent restenosis (ISR) models in Bama pigs after Neuroform EZ stent implantation, and observe and summarize their imaging and pathological characteristics.Methods:Thirteen healthy Bama pigs from Guangxi Province were chosen; carotid artery intima was injuried by balloon over-dilation; Neuroform EZ stents were implanted at the vascular injury sites to establish ISR models. Blood flow at areas accepted carotid artery stent implantation in Bama pigs was monitored by bedside color ultrasound every 2 weeks after surgery; once hemodynamic changes (acceleration or deceleration of the blood flow) in stents were detected, DSA, intravascular ultrasound (IVUS), optical coherence tomography (OCT) and high-resolution MRI (HR-MRI) were performed immediately. Bama pigs were then sacrificed and tissues at the stents were taken; HE staining was used to observe the pathological changes.Results:Thirteen Neuroform EZ stents were implanted into 13 Bama pigs after balloon over-dilation of the unilateral carotid arteries with a technical success rate of 100%. Hemodynamic changes in stents were detected in these 13 pigs (10 with acceleration and 3 with deceleration) at (12.46±3.57) weeks after stenting (ranged from 6-18 weeks); ISR of different degrees was found in all these 13 pigs by DSA with an average stenosis rate of (44.23±9.39)%. IVUS and OCT found that the main body of stents was covered by hyperplastic intima, and thickened intima resulted in local lumen stenosis; and obvious vascular wall enhancement in these lumens was shown on HR-MRI. HE staining showed rupture of intravascular internal elastic lamina and severely arterial intimal hyperplasia;and the hyperplastic intima was mainly composed of smooth muscle cells.Conclusion:Carotid artery ISR models in Bama pigs can be accurately and reliably established at approximately 12 weeks by tearing endovascular intima with balloon over-dilation and implanting Neuroform EZ stents, and multiple imaging and pathology methods confirm that ISR is caused by hyperplastic intima.