Transient severe motion during arterial phase in patients with Gadoxetic acid administration: Can a five hepatic arterial subphases technique mitigate the artifact?

Gadoxetic acid (Gd-EOB-DTPA) is a hepatocyte-specific magnetic resonance (MR) contrast agent, which has been increasingly used in recent years. However, it has been reported that Gd-EOB-DTPA related transient severe motion (TSM) is sometimes observed during the hepatic arterial phase of MR imaging, which may influence image quality. Since the hepatic arterial phase of contrast enhancement is used for the diagnosis of hepatocellular carcinoma, it is crucial to obtain a decent arterial phase imaging. The present study analyzed motion in patients receiving Gd-EOB-DTPA, comparing a single arterial phase acquisition to a five arterial phase acquisition to determine whether the multiphase acquisition was able to alleviate the TSM-related hepatic arterial MR imaging artifact. It was demonstrated that the single-phase acquisition failed to provide adequate diagnostic image quality in patients with TSM, whereas the multiphase arterial acquisition provided acceptable image quality in 20/22 (90.9%) patients with TSM. In conclusion, the results of the present study demonstrated that multiphase arterial acquisition is superior to single-phase arterial acquisition, mitigating arterial MR imaging artifacts caused by TSM after the administration of Gd-EOB-DTPA.

Serum cystatin c is not superior to serum creatinine for early diagnosis of contrast-induced nephropathy in patients who underwent angiography.

BACKGROUND: Iodiated contrast-induced nephropathy (CIN) is a serious complication of contrast-enhanced imaging. The aim of this study was to evaluate the diagnostic sensitivities and specificities of serum cystatin C (sCys C) and serum creatinine (sCr) for CIN and to further investigate difference of the incidence, risk factors, and in-hospital and 3-month prognosis of CIN according to sCys C criteria and sCr criteria. METHODS: We prospectively evaluated 213 patients who underwent angiography. The sCr and sCys C concentrations were detected before and at 48 hours, 72 hours after the procedure. The incidence, risk factors, and in-hospital and 3-month prognosis of CIN were analyzed. Receiver operating characteristic curve (ROC) analysis was performed for sCr and sCys C 48 hours after procedure. RESULTS: The incidence of CIN was 24.4% (sCys C criteria) and 8% (sCr criteria). Diabetes mellitus, dehydration, and hypoalbuminemia were independent risk factors for CIN. Area under the ROC of sCys C 48 hours after procedure was not superior to sCr (0.715 vs 0.790, P=.178). The mortality of patients with CIN in sCr criteria increased significantly (P<.05). CONCLUSION: In this study, the incidence and risk factors of CIN were related to diagnostic criteria. The sCys C was not superior to sCr for predicting CIN in the patients who underwent angiography.

MRI contrast agents: Classification and application (Review).

Magnetic resonance imaging (MRI) contrast agents are categorised according to the following specific features: chemical composition including the presence or absence of metal atoms, route of administration, magnetic properties, effect on the magnetic resonance image, biodistribution and imaging applications. The majority of these agents are either paramagnetic ion complexes or superparamagnetic magnetite particles and contain lanthanide elements such as gadolinium (Gd3+) or transition metal manganese (Mn2+). These elements shorten the T1 or T2 relaxation time, thereby causing increased signal intensity on T1-weighted images or reduced signal intensity on T2-weighted images. Most paramagnetic contrast agents are positive agents. These agents shorten the T1, so the enhanced parts appear bright on T1-weighted images. Dysprosium, superparamagnetic agents and ferromagnetic agents are negative contrast agents. The enhanced parts appear darker on T2-weighted images. MRI contrast agents incorporating chelating agents reduces storage in the human body, enhances excretion and reduces toxicity. MRI contrast agents may be administered orally or intravenously. According to biodistribution and applications, MRI contrast agents may be categorised into three types: extracellular fluid, blood pool and target/organ-specific agents. A number of contrast agents have been developed to selectively distinguish liver pathologies. Some agents are also capable of targeting other organs, inflammation as well as specific tumors.

Pulsed arterial spin labeling effectively and dynamically observes changes in cerebral blood flow after mild traumatic brain injury.

Cerebral blood flow is strongly associated with brain function, and is the main symptom and diagnostic basis for a variety of encephalopathies. However, changes in cerebral blood flow after mild traumatic brain injury remain poorly understood. This study sought to observe changes in cerebral blood flow in different regions after mild traumatic brain injury using pulsed arterial spin labeling. Our results demonstrate maximal cerebral blood flow in gray matter and minimal in the white matter of patients with mild traumatic brain injury. At the acute and subacute stages, cerebral blood flow was reduced in the occipital lobe, parietal lobe, central region, subcutaneous region, and frontal lobe. Cerebral blood flow was restored at the chronic stage. At the acute, subacute, and chronic stages, changes in cerebral blood flow were not apparent in the insula. Cerebral blood flow in the temporal lobe and limbic lobe diminished at the acute and subacute stages, but was restored at the chronic stage. These findings suggest that pulsed arterial spin labeling can precisely measure cerebral blood flow in various brain regions, and may play a reference role in evaluating a patient's condition and judging prognosis after traumatic brain injury.

Pituitary metastasis of choriocarcinoma: A case report.

Choriocarcinoma is an aggressive obstetric or gynecological neoplasm with a high malignant potential. It is a form of gestational trophoblastic disease and often secondary to hydatidiform mole, and intrauterine or ectopic pregnancy. Choriocarcinoma has a proclivity to metastasize to the lung, vagina, pelvis or liver in over 50% of patients, which always occurs in the early stage of the disease. With an appropriate amount of chemotherapy, the tumor may be treated effectively. However, pituitary metastasis of choriocarcinoma is extremely rare. To the best of our knowledge, no cases of choriocarcinoma metastasizing to the pituitary have been cited previously. Here, we report a case of choriocarcinoma that presented with pituitary metastasis.

Evaluation of hypointense liver lesions during hepatobiliary phase MR imaging in normal and cirrhotic livers: is increasing flip angle reliable?

Gd-EOB-DTPA is a newly developed liver specific magnetic resonance contrast agent, which is widely used for focal liver lesion (FLL) detection and liver function evaluation. However, it has been demonstrated that hepatocytes uptake of Gd-EOB-DTPA obviously decreased in cirrhotic liver, and cirrhotic liver parenchyma may show reduced enhancement in hepatobiliary phase, which would result in decreased liver-to-lesion contrast (LLC) and liver to lesion signal intensity ratio (LLSIR). Therefore, it is important to improve the image quality in cirrhotic liver, as it may alter therapeutic strategy. In this paper, we have shown adjustments of the flip angle (FA) provides a simple step to achieve better image quality for evaluation of FLLs, especially to those patients with severe liver cirrhosis. On the basis of our quantitative analysis, both of the LLC and the LLSIR with high FA protocol were always higher than those of low FA protocol. Additionally, on high FA images, more FLLs were detected, peritumoral invasion was found, boundary of the tumor was more remarkably, and better visualization of bile duct was observed. In conclusion, for the patient with severe liver cirrhosis, increasing FA can obviously improve the image quality, which is helpful for FLLs depiction.

Thalidomide Effects in Patients with Hereditary Hemorrhagic Telangiectasia During Therapeutic Treatment and in Fli-EGFP Transgenic Zebrafish Model.

BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease characterized by recurrent epistaxis, mucocutaneous telangiectasia, and arteriovenous malformations. The efficacy of traditional treatments for HHT is very limited. The aim of this study was to investigate the therapeutic role of thalidomide in HHT patients and the effect in FLI-EGFP transgenic zebrafish model. METHODS: HHT was diagnosed according to Shovlin criteria. Five HHT patients were treated with thalidomide (100 mg/d). The Epistaxis Severity Score (ESS), telangiectasia spots, and hepatic computed tomography angiography (CTA) were used to assess the clinical efficacy of thalidomide. The Fli-EGFP zebrafish model was investigated for the effect of thalidomide on angiogenesis. Dynamic real-time polymerase chain reaction assay, ELISA and Western blotting from patient's peripheral blood mononuclear cells and plasma were used to detect the expression of transforming growth factor beta 3 (TGF-ß3) messenger RNA (mRNA) and vascular endothelial growth factor (VEGF) protein before and after 6 months of thalidomide treatment. RESULTS: The average ESS before and after thalidomide were 6.966 ± 3.093 and 1.799 ± 0.627, respectively (P = 0.009). The "telangiectatic spot" on the tongue almost vanished; CTA examination of case 2 indicated a smaller proximal hepatic artery and decreased or ceased hepatic artery collateral circulation. The Fli-EGFP zebrafish model manifested discontinuous vessel development and vascular occlusion (7 of 10 fishes), and the TGF-ß3 mRNA expression of five patients was lower after thalidomide therapy. The plasma VEGF protein expression was down-regulated in HHT patients. CONCLUSIONS: Thalidomide reverses telangiectasia and controls nosebleeds by down-regulating the expression of TGF-ß3 and VEGF in HHT patients. It also leads to vascular remodeling in the zebrafish model.

Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging: A potential utility for the evaluation of regional liver function impairment following transcatheter arterial chemoembolization.

The present study aimed to evaluate regional liver function impairment following transcatheter arterial chemoembolization (TACE), assessed by magnetic resonance imaging (MRI) enhanced by gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA). Additionally, this study evaluated the associations between signal intensity and various clinical factors. A prospective study was conducted between March 2012 and May 2013 with a total of 35 patients. Gd-EOB-DTPA-enhanced MRI was performed 3-5 days after TACE therapy. The signal to noise ratio (SNR) was subsequently calculated for healthy liver tissue regions and peritumoral regions, prior to and 20 min after Gd-EOB-DTPA administration. The correlation between clinical factors and relative SNR was assessed using Pearson's correlation coefficient or Spearman's rank correlation coefficient. Prior to Gd-EOB-DTPA administration, the SNR values showed no significant difference (t=1.341, P=0.191) in healthy liver tissue regions (50.53±15.99; range, 11.25-83.46) compared with peritumoral regions (49.81±15.85; range, 12.34-81.53). On measuring at 20 min following Gd-EOB-DTPA administration, the SNR in healthy liver tissue regions (82.55±33.33; range, 31.45-153.02) was significantly higher (t=3.732, P<0.001) compared with that in peritumoral regions (75.77±27.41; range, 31.42-144.49). The relative SNR in peritumoral regions correlated only with the quantity of iodized oil used during TACE therapy (r=0.528, P=0.003); the age, gender, diameter and blood supply of the tumor, or Child-Pugh class of the patient did not correlate with relative SNR. Gd-EOB-DTPA-enhanced MRI may be an effective way to evaluate regional liver function impairment following TACE therapy.

Increased regional homogeneity in internet addiction disorder: a resting state functional magnetic resonance imaging study.

BACKGROUND: Internet addition disorder (IAD) is currently becoming a serious mental health problem among Chinese adolescents. The pathogenesis of IAD, however, remains unclear. The purpose of this study applied regional homogeneity (ReHo) method to analyze encephalic functional characteristic of IAD college students under resting state. METHODS: Functional magnetic resonanc image (fMRI) was performed in 19 IAD college students and 19 controls under resting state. ReHo method was used to analyze the differences between the average ReHo in two groups. RESULTS: The following increased ReHo brain regions were found in IAD group compared with control group: cerebellum, brainstem, right cingulate gyrus, bilateral parahippocampus, right frontal lobe (rectal gyrus, inferior frontal gyrus and middle frontal gyrus), left superior frontal gyrus, left precuneus, right postcentral gyrus, right middle occipital gyrus, right inferior temporal gyrus, left superior temporal gyrus and middle temporal gyrus. The decreased ReHo brain regions were not found in the IAD group compared with the control group. CONCLUSIONS: There are abnormalities in regional homogeneity in IAD college students compared with the controls and enhancement of synchronization in most encephalic regions can be found. The results reflect the functional change of brain in IAD college students. The connections between the enhancement of synchronization among cerebellum, brainstem, limbic lobe, frontal lobe and apical lobe may be relative to reward pathways.

[A functional MRI study in ADHD children with impulsivity].

OBJECTIVE: Impulsivity is one of the core symptoms of children with attention deficit hyperactivity disorder (ADHD). In order to understand the neuromechanism of the impulsive behaviors in ADHD children, this study investigated the specific functional areas of the brain by functional MRI. METHODS: The subjects consisted of 10 ADHD children with impulsivity, 7 ADHD children without impulsivity and 9 normal children. A functional MRI examination was performed when the subjects were instructed to finish GO and STOP tasks with the GO-STOP impulsivity paradigm. The MRI data during the two tasks of GO and STOP were averaged and the corresponding activation regions between groups were compared. RESULTS: The data from the GO task revealed that the main activation regions of the normal children included frontal pole (superior frontal gyrus, middle frontal gyrus and medial frontal gyrus); the main activation regions of ADHD children without impulsivity were cerebellum (posterior lobe and anterior lobe bouton) and cingulated gyrus; those of ADHD children with impulsivity were medial globus pallidus and insula. The data from the STOP task showed that the main activation regions of normal children included superior frontal gyrus and middle frontal gyrus; those of ADHD children without impulsivity were middle frontal gyrus and cingulate gyrus; those of ADHD children with impulsivity were uncus and putamen. The activation regions of ADHD children with impulsivity were much fewer than the other two groups. CONCLUSIONS: The behavior of impulsivity-control involves a number of specific functional areas in the cerebral cortex. Compared with normal children, ADHD children without impulsivity have weaker brain function and brain activation, and ADHD children with impulsivity demonstrate much fewer brain activation regions, worse brain function and little awareness of the cerebral cortex.

[Preliminary clinical application of percutaneous vertebroplasty].

OBJECTIVE: To investigate the clinical application of percutaneous vertebroplasty (PVP). METHODS: PVP was performed in 21 cases of 37 vertebral lesions,including 14 osteoporotic compression fractures, 6 metastases, 1 hemangioma,and 17 lesions in thoracic vertebra and 20 in lumbar. The procedures of PVP were as follows: The needle was inserted via percutaneous transpedicular approach or percutaneous posterolateral vertebral approach; the needle tip was placed at the junction of the anterior located the one third of the vertebral body; intraosseous venography was performed; and last bone cement was injected at 2-10 mL. The technical success rate, clinical efficacy and complications were observed after the procedure. Results The procedure was successful in 18 cases with 31 lesions,and the success rate according to the number of cases and vertebral lesions was 85.7% (18/21) and 83.8% (31/37), respectively. After the procedure, the numbers of complete remission, partial remission, mild remission and no remission were 10, 5, 2 and 1, respectively; and the total effective rate was 94.4% (17/18). Progressive compression did not occur. Three patients had transient neuropathy and recovered after physiotherapy. Other complications were insignificant; no severe complications occurred. Conclusion PVP is an effective and micro-traumatic treatment for patients with benign and malignant lesions in vertebral bodies.

[Relation between vascular endothelial growth factor and reoccurence-metastasis after transcatheter arterial chemoembolization in hepatocellar carcinoma].

OBJECTIVE: To investigate the relation between changes in serum vascular endothelial growth factor (VEGF) level after transcatheter arterial chemoembolization (TACE) and hepatocellular carcinoma (HCC) progression, especially in relation to metastasis. METHODS: Serum VEGF expression level, measured by quatitative sandwich enzyme-linked immunosorbent assay (ELISA, R&D system), was measured before, 3 days and 4 weeks after TACE in 30 patients with HCC. The development of metastasis was evaluated at the end of the third month after TACE. RESULTS: 1. The serum VEGF level in 30 patients was 154.47 +/- 90.17 pg/ml, 2. Post-TACE total serum VEGF level increased as compared with their basal level in 30 patients (P < 0.05) and serum VEGF level had a tendency to increase in patients with heterogeneous uptake of iodized oil and portal vein thrombosis. During the follow-up of 1 - 2 years, metastatic foci were found in 74% (20) patients with SVEGF increase, while none of the patients showing SVEGF decrease developed metastasis. CONCLUSION: Serum VEGF expression increase is associated with the development of metastasis in hepatocellular carcinoma after TACE.

[Influential factors to therapeutic efficacy of uterine artery embolization in the treatment of uterine fibroids].

OBJECTIVE: To investigate the therapeutic efficacy of uterine artery embolization in the treatment of uterine fibroids and to analyse the influential factors to the therapeutic efficacy. METHODS: Thirty-two patients with symptomatic uterine myomas were treated by superselective catheterization and embolization of bilateral uterine arteries using PVA particles. Patients were followed for 6 months after uterine artery embolization. Baseline symptoms and the volume of the fibroids were used as parameters to evaluate the therapeutic efficacy. Influential factors to therapeutic efficacy were analyzed. RESULTS: The clinical symptoms, especially heavy menstrual bleeding, were improved markedly. An average of 55.6% volume reduction of the fibroids was achieved during the 6 month follow-up. The submucosal and intramural location of the myomas reduced more in the volume compared with that of the subserosal location. CONCLUSION: Selective uterine artery embolization is effective for uterine myoma. Influential factors to the therapeutic efficacy may include: postprocedural vascular reconstruction in the fibroid, location of the fibroid, hemodynamic status of the fibroid, and the mode of embolization (unilateral or bilateral).

[Interventional therapy in the treatment of hysteromyoma].

OBJECTIVE: To study the clinical effect of bilateral super-selective arterial embolism therapy in the treatment of fibroids. METHODS: Twenty-eight cases of symptomatic uterine myoma were treated by Seldinger's bilateral super-selective uterine artery embolization. The changes of the clinical symptoms and volume of the uterus and myoma were observed with a mean follow-up of 3 and 6 months. RESULTS: Arteriography showed that hysteromyomas were bloody tumor, supplied by bilateral uterine arteries. The blood supply of uterine myoma could be occluded and pathological vessel signs of myoma disappeared after bilateral uterine artery embolization. With a mean follow-up of 3 and 6 months, the menorrhagia and menstrual cycles returned to normal and anemia was improved. The volume of the uterus and myoma was obviously smaller. CONCLUSION: Bilateral super-selective uterine artery embolization is a new, safe and effective method for the treatment of uterine myoma.

[Large-diameter balloon dilation in the treatment of esophageal achalasia].

OBJECTIVE: To evaluate the effectiveness and method of the large-diameter balloon dilation in the treatment of esophageal achalasia. METHODS: The hydrophilic guide wire and Wilson-Cook's Savary-Gilliard dilators were inserted into the stomach through the oral cavity under fluoroscopy. The Boston's balloon (35 mm in diameter) was introduced to the stricture site at the cardia through the guide wire and was inflated by the pressure pump (maximum pressure 15 PSI) with the method of "graded intermittent inflation". The balloon was inflated again to the maximum diameter for 3-5 times with the maximum of 8 times. RESULTS: The insertion of the Savary-Gilliard dilators and the Boston's balloon were technically successful in all the 204 patients. The cardia regions of the esophagus was ruptured and cured with conservative treatment in 2 patients. The follow-up time was 1-38 months (mean 18.5 months). Recurrent stenosis did not occur in any patient. The remission rate of dysphagia was 100%. The swallowing function was absolutely normal in 152 of the 204 patients (74.5%). CONCLUSION: The Boston's balloon dilatation is simple and effective in the treatment of esophageal achalasia. It is considered to be an alternative to surgical procedures.