2015年 · 第128卷第05期

Magnetic resonance imaging (MRI) has been utilized as a promising approach both in clinical application and in experimental research. MRI demonstrates superior ability to investigate the anatomical, metabolic, perfusion, functional, and molecular characteristic of various tissues and organs without radiation injury or invasiveness; therefore, it has been performed in the detection, diagnosis, staging, grading, and treatment of various diseases.

To achieve universal health insurance coverage, China has launched three phases of health care system reforms. The first round of reforms was embarked on in the mid-1980s with the introduction of market incentives. The second round began in 1997 with the introduction of the Urban Employee Basic Medical Insurance (UEBMI) scheme which provided health insurance coverage to all urban workers in addition to a long-term/historical scheme for government workers. Both the government and UEBMI schemes were limited to individual enrolment; however, dependents such as a spouse or child were not covered. The third phase of reforms began in 2003 with the launch of the New Rural Cooperative Medical Care System (NRCMS). This system covers rural residents at the household level. In 2007, the Urban Resident Basic Medical Insurance (URBMI) program was introduced that further expanded the insurance coverage to unemployed urban residents.^[1]UEBMI, URBMI, and NRCMS are acknowledged as basic medical insurance (BMI) and all schemes require payment of enrolment premiums.

Mild hypoxic-ischemic encephalopathy (HIE) injury is becoming the major type in neonatal brain diseases. The aim of this study was to assess brain maturation in mild HIE neonatal brains using total maturation score (TMS) based on conventional magnetic resonance imaging (MRI).

Totally, 45 neonates with clinically mild HIE and 45 matched control neonates were enrolled. Gestated age, birth weight, age after birth and postmenstrual age at magnetic resonance (MR) scan were homogenous in the two groups. According to MR findings, mild HIE neonates were divided into three subgroups: Pattern I, neonates with normal MR appearance; Pattern II, preterm neonates with abnormal MR appearance; Pattern III, full-term neonates with abnormal MR appearance. TMS and its parameters, progressive myelination (M), cortical infolding (C), involution of germinal matrix tissue (G), and glial cell migration bands (B), were employed to assess brain maturation and compare difference between HIE and control groups.

The mean of TMS was significantly lower in mild HIE group than it in the control group (mean ± standard deviation [SD] 11.62 ± 1.53 vs. 12.36 ± 1.26, P < 0.001). In four parameters of TMS scores, the M and C scores were significantly lower in mild HIE group. Of the three patterns of mild HIE, Pattern I (10 cases) showed no significant difference of TMS compared with control neonates, while Pattern II (22 cases), III (13 cases) all had significantly decreased TMS than control neonates (mean ± SD 10.56 ± 0.93 vs. 11.48 ± 0.55, P < 0.05; 12.59 ± 1.28 vs. 13.25 ± 1.29, P < 0.05). It was M, C, and GM scores that significantly decreased in Pattern II, while for Pattern III, only C score significantly decreased.

The TMS system, based on conventional MRI, is an effective method to detect delayed brain maturation in clinically mild HIE. The conventional MRI can reveal the different retardations in subtle structures and development processes among the different patterns of mild HIE.

A comprehensive assessment of various vascular anomalies and variants associated with venous pulsatile tinnitus (PT) by radiography is essential for therapeutic planning and improving the clinical outcome. This study evaluated the incidence of various vascular anomalies and variants on the PT side and determined whether these lesions occurred as multiple or single entities.

The dual-phase contrast-enhanced computed tomography images of 242 patients with unilateral venous PT were retrospectively reviewed. The vascular anomalies and variants on the symptomatic and asymptomatic sides were analyzed, and the incidences of anomalies or variants on each side were compared. The number of anomalies and variants on the symptomatic side in each patient was calculated.

(1) A total 170 patients (170/242) had more than one anomaly or variant on the symptomatic side, and 58 patients (58/242) had a single lesion on tomography. (2) There was a statistically significant difference in the incidence of dehiscent sigmoid plate (P = 0.000), lateral sinus stenosis (P = 0.014), high jugular bulb (P = 0.000), sigmoid sinus diverticulum (P = 0.000), jugular bulb diverticulum (P = 0.000), dehiscent jugular bulb (P = 0.000), and a large emissary vein (P = 0.006) between the symptomatic and asymptomatic sides. (3) Dehiscent sigmoid plate (86.4%) was the most frequent lesion on the symptomatic side, followed by lateral sinus stenosis (55.8%), high jugular bulb (47.1%), sigmoid sinus diverticulum (34.3%), jugular bulb diverticulum (13.6%), dehiscent jugular bulb (13.6%), large emissary vein (4.1%), sinus thrombosis (1.2%), and petrosquamosal sinus (0.8%).

Various vascular anomalies and variants occur more frequently on the venous PT side. Preliminary findings suggest that venous PT patients may have multiple vascular anomalies or variants on the symptomatic side.

Differentiating benign from malignant sinonsal lesions is essential for treatment planning as well as determining the patient’s prognosis, but the differentiation is often difficult in clinical practice. The study aimed to determine whether the combination of diffusion-weighted (DW) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can improve the performance in differentiating benign from malignant sinonasal tumors.

This retrospective study included 197 consecutive patients with sinonasal tumors (116 malignant tumors and 81 benign tumors). All patients underwent both DW and DCE-MRI in a 3-T magnetic resonance scanner. Two different settings of b values (0,700 and 0,1000 s/mm²) and two different strategies of region of interest (ROI) including whole slice (WS) and partial slice (PS) were used to calculate apparent diffusion coefficients (ADCs). A DW parameter with WS ADCs_b0,1000 and two DCE-MRI parameters (time intensity curve [TIC] and time to peak enhancement [Tpeak]) were finally combined to use in differentiating the benign from the malignant tumors in this study.

The mean ADCs of malignant sinonasal tumors (WS ADCs_b0,1000 = 1.084 × 10⁻³ mm²/s) were significantly lower than those of benign tumors (WS ADCs_b0,1000 = 1.617 × 10⁻³ mm²/s, P < 0.001). The accuracy using WS ADCs_b0,1000 alone was 83.7% in differentiating the benign from the malignant tumors (85.3% sensitivity, 81.2% specificity, 86.4% positive predictive value [PPV], and 79.5% negative predictive value [NPV]). The accuracy using DCE with Tpeak and TIC alone was 72.1% (69.1% sensitivity, 74.1% specificity, 77.5% PPV, and 65.1% NPV). Using DW-MRI parameter was superior than using DCE parameters in differentiation between benign and malignant sinonasal tumors (P < 0.001). The accuracy was 87.3% (90.5% sensitivity, 82.7% specificity, 88.2% PPV, and 85.9% NPV) using DW-MRI combined with DCE-MRI, which was superior than that using DCE-MRI alone or using DW-MRI alone (both P < 0.001) in differentiating the benign from the malignant tumors.

Diffusion-weighted combined with DCE-MRI can improve imaging performance in differentiating benign from malignant sinonasal tumors, which has the potential to improve diagnostic accuracy and to provide added value in the management for these tumors.

Neuroimaging studies have found that functional changes exist in patients with Parkinson’s disease (PD). However, the majority of functional magnetic resonance imaging (fMRI) studies in patients with PD are task-related and cross-sectional. This study investigated the functional changes observed in patients with PD, at both baseline and after 2 years, using resting-state fMRI. It further investigated the relationship between whole-brain spontaneous neural activity of patients with PD and their clinical characteristics.

Seventeen patients with PD underwent an MRI procedure at both baseline and after 2 years using resting-state fMRI that was derived from the same 3T MRI. In addition, 20 age- and sex-matched, healthy controls were examined using resting-state fMRI. The fractional amplitude of low-frequency fluctuation (fALFF) approach was used to analyze the fMRI data. Nonlinear registration was used to model within-subject changes over the scanning interval, as well as changes between the patients with PD and the healthy controls. A correlative analysis between the fALFF values and clinical characteristics was performed in the regions showing fALFF differences.

Compared to the control subjects, the patients with PD showed increased fALFF values in the left inferior temporal gyrus, right inferior parietal lobule (IPL) and right middle frontal gyrus. Compared to the baseline in the 2 years follow-up, the patients with PD presented with increased fALFF values in the right middle temporal gyrus and right middle occipital gyrus while also having decreased fALFF values in the right cerebellum, right thalamus, right striatum, left superior parietal lobule, left IPL, left precentral gyrus, and left postcentral gyrus (P < 0.01, after correction with AlphaSim). In addition, the fALFF values in the right cerebellum were positively correlated with the Unified PD Rating Scale (UPDRS) motor scores (r = 0.51, P < 0.05, uncorrected) and the change in the UPDRS motor score (r = 0.61, P < 0.05, uncorrected).

The baseline and longitudinal changes of the fALFF values in our study suggest that dysfunction in the brain may affect the regions related to cortico-striato-pallido-thalamic loops and cerebello-thalamo-cortical loops as the disease progresses and that alterations to the spontaneous neural activity of the cerebellum may also play an important role in the disease’s progression in patients with PD.

Previous studies have indicated that the cognitive deficits in patients with Alzheimer’s disease (AD) may be due to topological deteriorations of the brain network. However, whether the selection of a specific frequency band could impact the topological properties is still not clear. Our hypothesis is that the topological properties of AD patients are also frequency-specific.

Resting state functional magnetic resonance imaging data from 10 right-handed moderate AD patients (mean age: 64.3 years; mean mini mental state examination [MMSE]: 18.0) and 10 age and gender-matched healthy controls (mean age: 63.6 years; mean MMSE: 28.2) were enrolled in this study. The global efficiency, the clustering coefficient (CC), the characteristic path length (CpL), and "small-world" property were calculated in a wide range of thresholds and averaged within each group, at three different frequency bands (0.01–0.06 Hz, 0.06–0.11 Hz, and 0.11–0.25 Hz).

At lower-frequency bands (0.01–0.06 Hz, 0.06–0.11 Hz), the global efficiency, the CC and the "small-world" properties of AD patients decreased compared to controls. While at higher-frequency bands (0.11–0.25 Hz), the CpL was much longer, and the "small-world" property was disrupted in AD, particularly at a higher threshold. The topological properties changed with different frequency bands, suggesting the existence of disrupted global and local functional organization associated with AD.

This study demonstrates that the topological alterations of large-scale functional brain networks in AD patients are frequency dependent, thus providing fundamental support for optimal frequency selection in future related research.

The objective was to qualitatively and quantitatively evaluate hepatic metastases using computed tomography (CT) virtual noncontrast (VNC) spectral imaging in a retrospective analysis.

Forty hepatic metastases patients underwent CT scans including the conventional true noncontrast (TNC) and the tri-phasic contrast-enhanced dual energy spectral scans in the hepatic arterial, portal venous, and equilibrium phases. The tri-phasic spectral CT images were used to obtain three groups of VNC images including in the arterial (VNCa), venous (VNCv), and equilibrium (VNCe) phase by the material decomposition process using water and iodine as a base material pair. The image quality and the contrast-to-noise ratio (CNR) of metastasis of the four groups were compared with ANOVA analysis. The metastasis detection rates with the four nonenhanced image groups were calculated and compared using the Chi-square test.

There were no significant differences in image quality among TNC, VNCa and VNCv images (P > 0.05). The quality of VNCe images was significantly worse than that of other three groups (P < 0.05). The mean CNR of metastasis in the TNC and VNCs images was 1.86, 2.42, 1.92, and 1.94, respectively; the mean CNR of metastasis in VNCa images was significantly higher than that in other three groups (P < 0.05), while no statistically significant difference was observed among VNCv, VNCe and TNC images (P > 0.05). The metastasis detection rate of the four nonenhanced groups with no statistically significant difference (P > 0.05).

The quality of VNCa and VNCv images is identical to that of TNC images, and the metastasis detection rate in VNC images is similar to that in TNC images. VNC images obtained from arterial phase show metastases more clearly. Thus, VNCa imaging may be a surrogate to TNC imaging in hepatic metastasis diagnosis.

Amide proton transfer (APT) imaging has recently emerged as an important contrast mechanism for magnetic resonance imaging (MRI) in the field of molecular and cellular imaging. The aim of this study was to evaluate the feasibility of APT imaging to detect cerebral abnormality in patients with Alzheimer’s disease (AD) at 3.0 Tesla.

Twenty AD patients (9 men and 11 women; age range, 67–83 years) and 20 age-matched normal controls (11 men and 9 women; age range, 63–82 years) underwent APT and traditional MRI examination on a 3.0 Tesla MRI system. The magnetic resonance ratio asymmetry (MTR_asym) values at 3.5 ppm of bilateral hippocampi (Hc), temporal white matter regions, occipital white matter regions, and cerebral peduncles were measured on oblique axial APT images. MTR_asym (3.5 ppm) values of the cerebral structures between AD patients and control subjects were compared with independent samples t-test. Controlling for age, partial correlation analysis was used to investigate the associations between mini-mental state examination (MMSE) and the various MRI measures among AD patients.

Compared with normal controls, MTR_asym (3.5 ppm) values of bilateral Hc were significantly increased in AD patients (right 1.24% ± 0.21% vs. 0.83% ± 0.19%, left 1.18% ± 0.18% vs. 0.80%± 0.17%, t= 3.039, 3.328, P = 0.004, 0.002, respectively). MTR_asym (3.5 ppm) values of bilateral Hc were significantly negatively correlated with MMSE (right r = −0.559, P = 0.013; left r = −0.461, P = 0.047).

Increased MTR_asym (3.5 ppm) values of bilateral Hc in AD patients and its strong correlations with MMSE suggest that APT imaging could potentially provide imaging biomarkers for the noninvasive molecular diagnosis of AD.

To compare the diagnostic values of magnetic resonance elastography (MRE) and diffusion-weighted imaging (DWI) in staging hepatic fibrosis (HF) in an animal model.

This study consisted of 44 rabbits served as HF group and 9 normal rabbits. HF group was divided into two subgroups: Group A (n = 32) and Group B (n = 12). Rabbits in Group B were served as a complementary group when rabbits in Group A suddenly died during the study. Rabbits from control and Group A underwent abdominal MR imaging (MRI), MRE, and DWI. In Group A, random eight rabbits underwent MRI examinations at 4, 5, 6, 10 weeks after carbon tetrachloride oil subcutaneous injection. Liver stiffness (LS) and apparent diffusion coefficient (ADC) values of liver parenchyma were measured. The diagnostic performance of MRE and DWI for staging HF was compared using the receiver operating characteristic curve analysis on the basis of the histopathological analysis of HF.

Significant differences of LS and DWI values were present among HF stages (P < 0.005). The LS values measured on MRE (r = 0.838, P < 0.001) were more strongly correlated with the HF stages than with ADC values (r = −0.527, P < 0.001). The area under the receiver operating characteristic curve values of LS were significantly larger than those of DWI were for discriminating two stages of HF (0.979 vs. 0.712 for ≥ S1, 0.922 vs. 0.699 for ≥ S2). MRE showed higher specificity for predicting all stages of HF compared to DWI.

MRE more strongly correlated with the HF stages than DWI and is more specific in predicting all HF stages.

Diffusion weighted imaging (DWI), with the applying of intravoxel incoherent motion model, has showed promising results in obtaining additional information about microperfusion and tubular flow associated with morphologic changes in chronic kidney diseases. The study aims to evaluate the potential of T2-weighted signal intensity (SI) and DWI with mono- and bi-exponential models to reflect the serial changes on cisplatin (CP) induced rat renal fibrosis models.

Magnetic resonance exams were performed prior to and 2^nd day, 4^th day, 6^th day, 8^th day, 2^nd week, 3^rd week and 4^th week after CP injection at a 3.0T with an animal coil. Besides T2-weighted images (T2WI), DWI of 13 b values from 0 to 1500 s/mm² was acquired. Apparent diffusion coefficient (ADC), fluid fraction f, pure diffusivity D and pseudodiffusivity D* values were calculated. The regions of interest were placed on cortex (CO), outer stripe of the outer medulla (OM) and inner stripe of the outer medulla (OM), parameters were measured and compared among different time points. Five rats were scarified at each time point for pathological examination.

OM revealed remarkable hyperintense and broadened before it became an obscure thread, while CO demonstrated moderate hyperintense and IM didn’t show significant change on T2WI. On all three stripes, ADC values decreased firstly then kept increasing since the 4^th day; f values decreased on all stripes; D values had a tendency to increase with fluctuations but the changes didn’t achieve statistical significance; D* values increased at the 2^nd day then tended to be steady thereafter. Pathological findings revealed tubules epitheliums swelling followed by inflammation cells infiltration, interstitial fibrosis was observed since the 2^nd week.

All of T2-weighted SI, ADC, and biexponential models parameters vary during fibrotic process; biexponential model is superior to monoexponential model in separating changes of microperfusion together with tubular flow from pure diffusion.

China has achieved universal health insurance coverage. This study examined how patients and hospitals react to the different designs of the plans and to monitoring of patients by the local authority in the Chinese multiple health security schemes.

The sample for analysis consisted of 1006 orthopedic inpatients who were admitted between January and December 2011 at a tertiary teaching hospital located in Beijing. We conducted general linear regression analyses to investigate whether medical expenditure and length of stay differed according to the different incentives.

Patients under plans with lower copayment rates consumed significantly more medication compared with those under plans with higher copayment rates. Under plans with an annual ceiling for insurance coverage, patients spent significantly more in the second half of the year than in the first half of the year. The length of stay was shorter among patients when there were government monitoring and a penalty to the hospital service provider.

Our results indicate that the different designs and monitoring of the health security systems in China cause opportunistic behavior by patients and providers. Reformation is necessary to reduce those incentives, and improve equity and efficiency in healthcare use.

Depression is one of the most prevalent psychiatric diseases and significantly negatively impacts patients’ productivity, quality of life, and cognitive functions.^[1]According to a recent survey by the World Health Organization, it has been estimated that depression currently ranks the third in terms of disability-adjusted life years and will be the leading cause of disease and injury burden by 2030, surpassing cancer as well as cardiovascular and respiratory disease.^[2]This troubling situation, which has raised concern among the international field of psychiatry, challenges researchers worldwide to investigate the prevention and control of depression and identify the necessary funding to support this research. Given the expansive and interdisciplinary nature of biomedicine, no single researcher or institution can stay current on all developments within depression research. Thus, scientific collaboration becomes indispensable to make progress in biomedicine as it strengthens communication, encourages competency sharing, and facilitates the discovery of new scientific knowledge. Despite this fact, there have been few scientific publications to date regarding collaborative research within the field studying depression. Therefore, this article aimed to measure scientific collaborations at three levels – authors, institutions, and countries. By examining scientific collaboration, this article also identified hot topics in depression research, which represent the areas of focus that numerous researchers have decided to have substantial potential to prevent and cure this pervasive disease.

Despite a higher incidence of postoperative complications, splenectomy is a commonly performed procedure for splenic space-occupying lesions. A retrospective analysis of 2796 splenectomy patients showed that 119 patients (4.25%) had postoperative bacterial infections, and 71 (60%) died due to infections.^[1]Therefore, emphasis on the preservation of splenic function has been raised that is, at least 25% of the spleen’s weight must be retained to maintain splenic immunologic functions, with the prerequisite of adequate arterial blood supply. After the partial splenectomy was firstly performed in 1980s, the first case of laparoscopic partial splenectomy was reported in the literature in 1990s.^[2]Laparoscopic partial splenectomy has currently become a common option for many spleen diseases. However, laparoscopic partial splenectomy specific for solid hemangioma, which is at a high risk of bleeding, is not commonly reported in the literature. This study reviewed the six cases of laparoscopic partial splenectomy for the splenic hemangioma to evaluate whether the surgical procedure was feasible and safe.

Horseshoe kidney is a type of renal fusion by the lower poles anomaly during embryogenesis. Polycystic kidney that occurs in adults is an autosomal dominant disease due to the genetic mutations leading to the expression of the proteins polycystin 1 (ADPKD1) and polycystin 2 (ADPKD2). The two kidney diseases are common congenital disorders respectively, but it is very rare for one patient to have both anomalies simultaneously with the incidence of 1 in 134,000–1 in 8,000,000.^[1,2]

To the Editor: In August 2013, a 22-year-old female was referred to a psychiatric hospital with 6 months history of insomnia, suicidal thought, social withdrawal, irritability and persecutory delusion. She was given the diagnosis of schizophrenia and started on risperidone and chlorpromazine, which were stopped abruptly after 1-week due to lack of any improvement in her mental state. Two days later, she developed recurrent episodes of generalized tonic-clonic seizures and was transferred to our hospital in a comatose state. She was emergently intubated and started on phenobarbital and valproic acid. Per family, the patient also had 6 months history of dizziness, fatigue, and scanty menses. Cushing’s syndrome was suspected but serum cortisol was 534.6 nmol/L at 800 h, 445.5 nmol/L at 1600 h, and 382.7 nmol/L at 2400 h (normal range: 85.3–618.0 nmol/L); corticotrophin was 5.1 ng/L at 800 h, ≤5 ng/L at 1600 h, and ≤5 ng/L at 2400 h (normal range: 0–46.0 ng/L); 24 h urinary 17-hydroxysteroid was 15.7 µmol (normal range: 5.5–22.2 µmol/day).

To the Editor: The anti-tuberculosis (TB) therapy can cause various drug adverse effects including hepatotoxicity, nephrotoxicity and skin rash.^[1,2]There are some case reports about interstitial lung disease (ILD) such as pneumonitis caused by isoniazid (INH), rifampin (RFP), ethambutol (EMB).^[3,4]The causative drug was discontinued permanently or re-administrated after desensitization therapy. But the pulmonary fibrosis induced by short anti-TB medication was very rare. We herein report a case of pulmonary fibrosis due probably to INH, which was developed after 3 weeks of anti-TB treatment.

To the Editor: We report a strategy for an asymptomatic anastomotic pseudoaneurysm that occurred 30 years after aorta surgery.

To the Editor: Mikulicz’s disease (MD), also known as benign lymphoepithelial lesion, refers to idiopathic, bilateral, painless, and symmetrical swelling of the lacrimal, parotid, and submandibular glands. The complications of MD include autoimmune pancreatitis, retroperitoneal fibrosis, tubulointerstitial nephritis, autoimmune hypophysitis, and Riedel’s thyroiditis, all of which show elevated serum immunoglobulin G4 (IgG4) levels and prominent infiltration of IgG4-positive plasmacytes. Members of two Japanese research teams from the Ministry of Health, Labor and Welfare agreed, at their second meeting in Kanazawa in 2010, to use the term "IgG4-related disease (IgG4-RD)" to identify this clinical disease entity. IgG4-RD mainly affects middle-aged to elderly men. It often involves one or multiple organs. As its clinical symptoms are relatively mild, the condition usually comes to clinical attention as a result of organ swelling or damage.^[1]Asymptomatic IgG4-related lymphadenopathy is common, and sometimes can be the initial or only manifestation.^[2]Comprehensive clinical diagnostic criteria (CCD criteria) for IgG4-RD were introduced by Japan in 2012.^[3]Here, we report a typical case of IgG4-RD, who was mis-diagnosed 5 years ago.

To the Editor: A 49-year-old woman was admitted with hypertension and diabetes. Electrocardiogram demonstrated inverted T waves in V_{1- 6}. Blood pressure was 180/110 mmHg. Total cholesterol was 4.82 mmol/L, high-density lipoprotein-cholesterol was 1.12 mmol/L, and low-density lipoprotein-cholesterol was 3.08 mmol/L. To exclude coronary heart disease and renal artery stenosis, coronary angiography (CAG) and renal artery angiography were performed simultaneously through the right radial artery by 5 Fr Terumo Optitorque TIG catheter, the results showed that both coronary and renal arteries were normal. After CAG, multifunctional catheter was also used for renal artery angiography. But she complained of a gradually aggravated pain in the right waist immediately after the right renal artery angiography, and blood pressure was decreased to 90/40 mmHg half an hour later. The abdominal ultrasonography indicated a perirenal hematoma around the right kidney [Figure 1a]. We finally found that the right renal artery angiography was just slightly emerged by an accident injection from renal capsular artery above the right renal artery [Figure 1b]. Then an appropriate dosage of protamine was given by venous injection, vasopressor agents were used at the early stage, and the condition become stable after transfusion of totally 1600 ml red blood cells. She was discharged 3 weeks later.

To the Editor: Large granular lymphocytic leukemia (LGLL) is a rare chronic clonal lymphoproliferative disease characterized by a persistent increase in large granular lymphocytes, which are large lymphocytes with a low nucleus to cytoplasm ratio and an abundant cytoplasm with azurophilic granules.^[1]Here we report two cases diagnosed as refractory LGLL treated with porcine antihuman thymocyte immunoglobulin (ATG) in West China Hospital.