【Abstract】ObjectiveTo evaluate the role of MRA, IPVG and DUS in the hemodynamics studies of portal hypertension. MethodsThirtyeight patients with portal hypertension were examined with Philips Gyroscan 1.0 Tesla MR imaging system. 3DDCE MRA and 2DPC MR were used for study of portal venous anatomy and its hemodynamics. The results were compared with those obtained from IPVG and DUS. Results3DDCE MRA could clearly display the anatomical imaging of portal venous system and its imaging quality was better than that of IPVG. The data of hemodynamics from 2DPC MR including diameter, blood velocity and blood flow were closely correlated to those from DUS. ConclusionAs a noninvasive technique, MRA can display the anatomy of portal venous system and measure its hemodynamics exactly. It should be applied as the first choice in hemodynamics evaluation for portal hypertension.
Objective To assess the overall diagnostic value of magnetic resonance angiography ( MRA) in patients with suspected pulmonary embolism. Methods A search in Cochrane Library,Medline,Embase,Wanfang and China Biology Medicine disc ( CBMdisc) was performed to identify relevant English and Chinese language publications from1990 to 2012. Criteria for inclusion was established based on validity criteria for diagnostic research published by the Cochrane Methods Group on Screening and Diagnostic Tests. Subsequently, the characteristics of the included articles were appraised and extracted. Statistical analysis was performed byMeta-disc version1. 4. Heterogeneity of the included articles was tested, which was used to select proper effect model to calculate pooled weighted sensitivity, specificity, positive likelihood ratio and negative likelihood ratio. Summary receiver opertating characteristic ( SROC) curve was performed and the area under the curve ( AUC) was calculated.Results 6 literatures in English were finally collected, with a total of 534 cases recruited into the study. Heterogeneity was found because of threshold effect. A Metaanalysis was performed using the randomeffect model. The value of the positive likelihood ratio and negative likelihood ratio of MRA with 95% confidence interval ( 95% CI) were 32. 392( 15. 951-65. 778) and 0. 217( 0. 160-0. 294) , respectively. The pooled weighted sensitivity and specificity were 0. 800 ( 0. 728-0. 860)and 0. 984( 0. 966-0. 994) , respectively. The AUC of SROC was 0. 9783. Conclusions MRA has certain diagnosis value for pulmonary embolismwith high sensitivity and specificity. MRA may be the best choice for some patients with renal mysfunction and allergy to radiographic contrast material. Otherwise, patients who are detected by MRA avoid exposure to ionizeing radiation.
ObjectiveTo observe the characteristics of magnetic resonance angiography of (MRA) ophthalmic artery in patients with diabetic retinopathy (DR).MethodsA total of 36 eyes of DR patients (DR group) diagnosed by clinical examination were included in the study. Among them, there were 42 eyes in 21 males and 15 eyes in 15 females. The average age was 55.2 years old. The average duration of diabetes was 7.56 years. All eyes were examined by MRA and fluorescein fundus angiography (FFA) in the ophthalmic artery. At the same time, 24 eyes of 12 patients were examined by computed tomography angiography (CTA). Twenty-two healthy volunteers with age and gender matching were selected as the control group. Among them, there were 13 males and 9 females. All patients underwent MRA examination of the ophthalmic artery; at the same time, 5 eyes of 5 eyes were examined by CTA. MRA and CTA were classified into three grades according to the development condition and shape change of the ophthalmic artery. 0 grade : no abnormality; grade Ⅰ: mild lesion; grade Ⅱ: obvious lesion. According to the results of FFA examination, it was divided into no obvious disease stage, background stage, proliferative stage, proliferative stage. The morphological features of the MRA of the ophthalmic artery in the DR group and the control group were compared. The relationship between the MRA grading of the ophthalmic artery and the FFA staging was observed in the DR group. The consistency analysis between the MRA and CTA grades of the ophthalmic artery in the DR group was performed by Kappa test; the relationship between the MRA grade and the FFA staging of the ophthalmic artery was analyzed by Spearson correlation analysis of the same data with two-way ordered attributes.ResultsIn 44 eyes of the control group, the MRA in grade 0 and Ⅰ of the ophthalmic artery were 41 and 3 eyes, respectively; all eyes of the CTA examination of the ophthalmic artery were grade 0. In 72 eyes of the DR group, the MRA in grade 0, Ⅰ, and Ⅱ of the ophthalmic artery were 28, 28, and 16 eyes, respectively. Among the 24 eyes examined by CTA, there were 13, 6, and 5 eyes in grade 0, Ⅰ, and Ⅱ, respectively. In the DR group, the classification of MRA and CTA of the ophthalmic artery was highly consistent (Kappa value = 0.86). There were significant differences in the number of eyes with different grades of MRA in the DR group and the control group (Z=-5.74, P=0.000). In 72 eyes of the DR group, there were 8, 12, 22, and 30 eyes in no obvious disease stage, background stage, proliferative stage, and proliferative stage, respectively. Correlation analysis showed that there was a significant correlation between MRA grading and FFA staging in the DR group (r=0.405, P=0.000).ConclusionsMRA can show the changes of ophthalmic artery morphology and reflect DR staging to a certain extent. It has a high consistency with FFA vascular changes.