BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and H...BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and HFS caused by NVC. The judgement of NVC is a critical step in the preoperative evaluation of MVD, which is related to the effect of MVD treatment. Magnetic resonance imaging(MRI) technology has been used to detect NVC prior to MVD for several years. Among many MRI sequences, three-dimensional time-of-flight magnetic resonance angiography(3D TOF MRA) is the most widely used. However, 3D TOF MRA has some shortcomings in detecting NVC. Therefore, 3D TOF MRA combined with high resolution T2-weighted imaging(HR T2WI) is considered to be a more effective method to detect NVC.AIM To determine the value of 3D TOF MRA combined with HR T2WI in the judgment of NVC, and thus to assess its value in the preoperative evaluation of MVD.METHODS Related studies published from inception to September 2022 based on PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Studies that investigated 3D TOF MRA combined with HR T2WI to judge NVC in patients with TN or HFS were included according to the inclusion criteria. Studies without complete data or not relevant to the research topics were excluded. The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. The publication bias of the included literature was examined by Deeks’ test. An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize data. Data analysis was performed using the MIDAS module of statistical software Stata 16.0. Two independent investigators extracted patient and study characteristics, and discrepancies were resolved by consensus. Individual and pooled sensitivities and specificities were calculated. The I_(2) statistic and Q test were used to test heterogeneity. The study was registered on the website of PROSERO(registration No. CRD42022357158).RESULTS Our search identified 595 articles, of which 12(including 855 patients) fulfilled the inclusion criteria. Bivariate analysis showed that the pooled sensitivity and specificity of 3D TOF MRA combined with HR T2WI for detecting NVC were 0.96 [95% confidence interval(CI): 0.92-0.98] and 0.92(95%CI: 0.74-0.98), respectively. The pooled positive likelihood ratio was 12.4(95%CI: 3.2-47.8), pooled negative likelihood ratio was 0.04(95%CI: 0.02-0.09), and pooled diagnostic odds ratio was 283(95%CI: 50-1620). The area under the receiver operating characteristic curve was 0.98(95%CI: 0.97-0.99). The studies showed no substantial heterogeneity(I2 = 0, Q = 0.001 P = 0.50).CONCLUSION Our results suggest that 3D TOF MRA combined with HR T2WI has excellent sensitivity and specificity for judging NVC in patients with TN or HFS. This method can be used as an effective tool for preoperative evaluation of MVD.展开更多
Purpose: To evaluate respiratory-triggered three-dimensional (3D) true steady-state free-precession (SSFP) projection magnetic resonance angiographic sequences with time-spatial labeling inversion pulse (Time-SLIP) fo...Purpose: To evaluate respiratory-triggered three-dimensional (3D) true steady-state free-precession (SSFP) projection magnetic resonance angiographic sequences with time-spatial labeling inversion pulse (Time-SLIP) for visualizing the hepatic arteries and to optimize the image acquisition protocol. Materials and Methods: A 1.5-T clinical magnetic resonance imager was used to perform abdominal magnetic resonance angiography (MRA) in 25 consecutive patients before transcatheter arterial chemoembolization or surgery. We compared two selective space-labeling inversion pulse (tag pulse) patterns (Patterns I and II, oblique and parallel tag pulses, respectively). Two experienced radiologists evaluated the number of hepatic arterial branches visible on the acquired MRA images, and the results were referenced with those on images from intra-arterial digital subtraction angiography. Results: Images were acquired from all patients. The two radiologists clearly visualized branches of the left and right hepatic arteries. More peripheral hepatic arterial branches were identified in MRA images captured by using tag pulse Pattern I than in those acquired by using Pattern II (P P > 0.05). Conclusion: Non-contrast-enhanced Time-SLIP hepatic MRA with true SSFP allowed selective visualization of peripheral hepatic vessels.展开更多
The optimal velocity encoding of phase-contrast magnetic resonance angiography （PC MRA） in measuring cerebral blood flow volume （BFV） ranges from 60 to 80 cm/s. To verify the accuracy of two-dimensional （2D） PC ...The optimal velocity encoding of phase-contrast magnetic resonance angiography （PC MRA） in measuring cerebral blood flow volume （BFV） ranges from 60 to 80 cm/s. To verify the accuracy of two-dimensional （2D） PC MRA, the present study localized the region of interest at blood vessels of the neck using PC MRA based on three-dimensional time-of-flight sequences, and the velocity encoding was set to 80 cm/s. Results of the measurements showed that the error rate was 7.0±6.0% in the estimation of BFV in the internal carotid artery, the external carotid artery and the ipsilateral common carotid artery. There was no significant difference, and a significant correlation in BFV between internal carotid artery ＋ external carotid artery and ipsilateral common carotid artery. In addition, the BFV of the common carotid artery was correlated with that of the ipsilateral internal carotid artery. The main error was attributed to the external carotid artery and its branches. Therefore, after selecting the appropriate scanning parameters and protocols, 2D PC MRA is more accurate in the determination of BFV in the carotid arteries.展开更多
OBJECTIVE: To evaluate the value of magnetic resonance imaging (MRI) and three dimensional (3D) contrast magnetic resonance angiography (MRA) in the diagnosis of complications of simultaneous pancreas-kidney transplan...OBJECTIVE: To evaluate the value of magnetic resonance imaging (MRI) and three dimensional (3D) contrast magnetic resonance angiography (MRA) in the diagnosis of complications of simultaneous pancreas-kidney transplantation (SPKT), as confirmed by biopsy and digital subtraction angiography (DSA). METHODS: Five MR examinations of five patients were performed within 28 days to 2 years after surgery on GE 1.5T MR system. Imaging techniques included axial and sagittal chemical fat-suppressed T1-weighted image (T1WI) and T2-weighted image (T2WI), additional contrast axial or saggital chemical fat-suppressed T1WI were obtained after 3D contrast MRA for calculating the mean percentage of the parenchymal enhancement (MPPE) of the pancreas and kidney. 3D contrast MRA was performed with Smartprep technique. MRA data were analyzed with maximum intensity projection (MIP) and multi-planner reformat (MPR). RESULTS: In five cases of transplant pancreases, MRI found two normal pancreas grafts, one case of acute rejection, one case of chronic rejection with 70% fibrosis and one case of late pancreatitis. In five transplant kidneys, MRI detected four normal kidney grafts and one case of acute rejection with infarction. MPPE could distinguish infarction from other complications. 3D contrast MRA could display vascular complications of SPKT, such as stenosis or occlusion, aneurysm formation of transplanted vessels and narrowing at the site of anastomosis, as confirmed by DSA. CONCLUSION: With combined application of MRI and 3D contrast MRA, complications of SPKT can be clearly identified.展开更多
目的研究高分辨率磁共振成像(high-resolution magnetic resonance imaging,HR-MRI)在颅内动脉瘤测量中的应用价值,并与三维数字减影血管造影(three-dimensional DSA,3D-DSA)、三维时间飞跃法磁共振血管成像(threedimensional time of f...目的研究高分辨率磁共振成像(high-resolution magnetic resonance imaging,HR-MRI)在颅内动脉瘤测量中的应用价值,并与三维数字减影血管造影(three-dimensional DSA,3D-DSA)、三维时间飞跃法磁共振血管成像(threedimensional time of fl ight MRA,3D-TOF MRA)作对比。材料与方法选取2013年10月至2015年3月我院神经外科诊断为颅内动脉瘤的患者25例。患者首先行3D-TOF MRA及HR-MRI扫描,并于1周内行DSA检查。分别在3D-TOF MRA、HR-MRI和3D-DSA图像上测量动脉瘤的宽径,采用配对t检验两两比较3D-TOF MRA、HR-MRI与3D-DSA在测量颅内动脉瘤宽径方面的差异。P<0.05为差异有统计学意义。结果 HR-MRI与3D-DSA、HR-MRI与3D-TOF MRA在测量颅内动脉瘤宽径方面的差异[平均差值分别为(3.16±2.66)mm、(5.15±4.89)mm]均有统计学意义(P1<0.05,P2<0.05),3D-DSA与3D-TOF MRA在测量颅内动脉瘤宽径方面的差异[平均差值为(2.53±5.18)mm]无统计学意义(P3>0.05)。结论 HRMRI与3D-DSA、HR-MRI与3D-TOF MRA在显示颅内动脉瘤宽径方面有差异,可能HR-MRI能更准确地显示颅内动脉瘤实际大小,具有较高的临床应用价值。展开更多
目的:探讨压缩感知技术在头颅时间飞跃法磁共振血管造影(TOF-MRA)中的应用价值,并比较不同加速因子对成像的影响。方法:选取在医院同时行头颅并行采集(PI)TOF-MRA和压缩感知(CS)TOF-MRA扫描的21例受试者,根据CS采用的加速因子系数(AF)4....目的:探讨压缩感知技术在头颅时间飞跃法磁共振血管造影(TOF-MRA)中的应用价值,并比较不同加速因子对成像的影响。方法:选取在医院同时行头颅并行采集(PI)TOF-MRA和压缩感知(CS)TOF-MRA扫描的21例受试者,根据CS采用的加速因子系数(AF)4.6和10.3,分别设CS5和CS10,每例患者获得PI、CS5和CS10的3组TOF-MRA图像。定性分析3组图像的诊断质量,分支小血管显示能力,定量分析3组图像的信噪比(SNR)、对比噪声比(CNR)和血管边缘锐利度。结果:PI、CS5和CS10扫描时间分别为4 min 48 s、5 min 4 s和2 min 31 s。图像质量定性评价中CS5优于PI,差异有统计学意义(t=3.062,P<0.05),CS10与PI相当(P=0.086)。图像SNR和CNR定量评估中CS5优于CS10,差异有统计学意义(t=2.744,t=2.428;P<0.05);PI与CS差异无统计学意义。CS图像血管边缘锐利度优于PI,且CS5优于CS10,差异有统计学意义(t=3.729,P<0.05);CS5对分支小血管显示能力最佳。结论:CS技术可缩短头颅TOF-MRA扫描时间,提供与常规PI-TOF相当或更高质量的图像,具有很高的临床应用价值。展开更多
基金Supported by the Key Research and Development Plan of Shaanxi Province,No.2021SF-298.
文摘BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and HFS caused by NVC. The judgement of NVC is a critical step in the preoperative evaluation of MVD, which is related to the effect of MVD treatment. Magnetic resonance imaging(MRI) technology has been used to detect NVC prior to MVD for several years. Among many MRI sequences, three-dimensional time-of-flight magnetic resonance angiography(3D TOF MRA) is the most widely used. However, 3D TOF MRA has some shortcomings in detecting NVC. Therefore, 3D TOF MRA combined with high resolution T2-weighted imaging(HR T2WI) is considered to be a more effective method to detect NVC.AIM To determine the value of 3D TOF MRA combined with HR T2WI in the judgment of NVC, and thus to assess its value in the preoperative evaluation of MVD.METHODS Related studies published from inception to September 2022 based on PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Studies that investigated 3D TOF MRA combined with HR T2WI to judge NVC in patients with TN or HFS were included according to the inclusion criteria. Studies without complete data or not relevant to the research topics were excluded. The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. The publication bias of the included literature was examined by Deeks’ test. An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize data. Data analysis was performed using the MIDAS module of statistical software Stata 16.0. Two independent investigators extracted patient and study characteristics, and discrepancies were resolved by consensus. Individual and pooled sensitivities and specificities were calculated. The I_(2) statistic and Q test were used to test heterogeneity. The study was registered on the website of PROSERO(registration No. CRD42022357158).RESULTS Our search identified 595 articles, of which 12(including 855 patients) fulfilled the inclusion criteria. Bivariate analysis showed that the pooled sensitivity and specificity of 3D TOF MRA combined with HR T2WI for detecting NVC were 0.96 [95% confidence interval(CI): 0.92-0.98] and 0.92(95%CI: 0.74-0.98), respectively. The pooled positive likelihood ratio was 12.4(95%CI: 3.2-47.8), pooled negative likelihood ratio was 0.04(95%CI: 0.02-0.09), and pooled diagnostic odds ratio was 283(95%CI: 50-1620). The area under the receiver operating characteristic curve was 0.98(95%CI: 0.97-0.99). The studies showed no substantial heterogeneity(I2 = 0, Q = 0.001 P = 0.50).CONCLUSION Our results suggest that 3D TOF MRA combined with HR T2WI has excellent sensitivity and specificity for judging NVC in patients with TN or HFS. This method can be used as an effective tool for preoperative evaluation of MVD.
文摘Purpose: To evaluate respiratory-triggered three-dimensional (3D) true steady-state free-precession (SSFP) projection magnetic resonance angiographic sequences with time-spatial labeling inversion pulse (Time-SLIP) for visualizing the hepatic arteries and to optimize the image acquisition protocol. Materials and Methods: A 1.5-T clinical magnetic resonance imager was used to perform abdominal magnetic resonance angiography (MRA) in 25 consecutive patients before transcatheter arterial chemoembolization or surgery. We compared two selective space-labeling inversion pulse (tag pulse) patterns (Patterns I and II, oblique and parallel tag pulses, respectively). Two experienced radiologists evaluated the number of hepatic arterial branches visible on the acquired MRA images, and the results were referenced with those on images from intra-arterial digital subtraction angiography. Results: Images were acquired from all patients. The two radiologists clearly visualized branches of the left and right hepatic arteries. More peripheral hepatic arterial branches were identified in MRA images captured by using tag pulse Pattern I than in those acquired by using Pattern II (P P > 0.05). Conclusion: Non-contrast-enhanced Time-SLIP hepatic MRA with true SSFP allowed selective visualization of peripheral hepatic vessels.
基金the Medical Program of Scientific & Technical Foundation in Xiamen in 2008, No. 3502Z20084028
文摘The optimal velocity encoding of phase-contrast magnetic resonance angiography （PC MRA） in measuring cerebral blood flow volume （BFV） ranges from 60 to 80 cm/s. To verify the accuracy of two-dimensional （2D） PC MRA, the present study localized the region of interest at blood vessels of the neck using PC MRA based on three-dimensional time-of-flight sequences, and the velocity encoding was set to 80 cm/s. Results of the measurements showed that the error rate was 7.0±6.0% in the estimation of BFV in the internal carotid artery, the external carotid artery and the ipsilateral common carotid artery. There was no significant difference, and a significant correlation in BFV between internal carotid artery ＋ external carotid artery and ipsilateral common carotid artery. In addition, the BFV of the common carotid artery was correlated with that of the ipsilateral internal carotid artery. The main error was attributed to the external carotid artery and its branches. Therefore, after selecting the appropriate scanning parameters and protocols, 2D PC MRA is more accurate in the determination of BFV in the carotid arteries.
文摘OBJECTIVE: To evaluate the value of magnetic resonance imaging (MRI) and three dimensional (3D) contrast magnetic resonance angiography (MRA) in the diagnosis of complications of simultaneous pancreas-kidney transplantation (SPKT), as confirmed by biopsy and digital subtraction angiography (DSA). METHODS: Five MR examinations of five patients were performed within 28 days to 2 years after surgery on GE 1.5T MR system. Imaging techniques included axial and sagittal chemical fat-suppressed T1-weighted image (T1WI) and T2-weighted image (T2WI), additional contrast axial or saggital chemical fat-suppressed T1WI were obtained after 3D contrast MRA for calculating the mean percentage of the parenchymal enhancement (MPPE) of the pancreas and kidney. 3D contrast MRA was performed with Smartprep technique. MRA data were analyzed with maximum intensity projection (MIP) and multi-planner reformat (MPR). RESULTS: In five cases of transplant pancreases, MRI found two normal pancreas grafts, one case of acute rejection, one case of chronic rejection with 70% fibrosis and one case of late pancreatitis. In five transplant kidneys, MRI detected four normal kidney grafts and one case of acute rejection with infarction. MPPE could distinguish infarction from other complications. 3D contrast MRA could display vascular complications of SPKT, such as stenosis or occlusion, aneurysm formation of transplanted vessels and narrowing at the site of anastomosis, as confirmed by DSA. CONCLUSION: With combined application of MRI and 3D contrast MRA, complications of SPKT can be clearly identified.
文摘目的:探讨压缩感知技术在头颅时间飞跃法磁共振血管造影(TOF-MRA)中的应用价值,并比较不同加速因子对成像的影响。方法:选取在医院同时行头颅并行采集(PI)TOF-MRA和压缩感知(CS)TOF-MRA扫描的21例受试者,根据CS采用的加速因子系数(AF)4.6和10.3,分别设CS5和CS10,每例患者获得PI、CS5和CS10的3组TOF-MRA图像。定性分析3组图像的诊断质量,分支小血管显示能力,定量分析3组图像的信噪比(SNR)、对比噪声比(CNR)和血管边缘锐利度。结果:PI、CS5和CS10扫描时间分别为4 min 48 s、5 min 4 s和2 min 31 s。图像质量定性评价中CS5优于PI,差异有统计学意义(t=3.062,P<0.05),CS10与PI相当(P=0.086)。图像SNR和CNR定量评估中CS5优于CS10,差异有统计学意义(t=2.744,t=2.428;P<0.05);PI与CS差异无统计学意义。CS图像血管边缘锐利度优于PI,且CS5优于CS10,差异有统计学意义(t=3.729,P<0.05);CS5对分支小血管显示能力最佳。结论:CS技术可缩短头颅TOF-MRA扫描时间,提供与常规PI-TOF相当或更高质量的图像,具有很高的临床应用价值。
