Towards medical imaging of drug photoactivation:Development of light responsive magnetic resonance imaging and chemical exchange saturation transfer contrast agents

In recent years,the use of light to selectively and precisely activate drugs has been developed along the fundamental concepts of photopharmacology.One of the key methods in this field relies on transiently silencing the drug activity with photocleavable protecting groups(PPGs).To effectively utilize light-activated drugs in future medical applications,physicians will require a reliable method to assess whether light penetrates deep enough into the tissues to activate the photoresponsive theragnostic agents.Here,we describe the development and evaluation of magnetic resonance(MR)imaging agents that allow for the detection of light penetration and drug activation in the tissues using non-invasive whole-body magnetic resonance imaging(MRI)and chemical exchange saturation transfer(CEST)-MRI modalities.The approach relies on the use of PPG-protected MR contrast agents,which upon irradiation with light change their imaging signal.A Gadolinium(III)-based MRI contrast agent is presented that undergoes a significant change in relaxivity(25%)upon uncaging,providing a reliable indicator of lightinduced cargo release.Additionally,we introduce the first light-responsive CESTMRI imaging agent,enabling positive signal enhancement(off-to-on)upon light activation,offering a novel approach to visualize the activation of photoactive agents in living tissues.This research provides a proof-of-principle for the noninvasive,whole-body imaging of light penetration and drug activation with high temporal resolution characteristic of MR methods.

Effects of psychological nursing in Parkinson's related depression patients undergoing functional magnetic resonance imaging:A randomized controlled trial

BACKGROUND Patients with Parkinson’s disease(PD)often experience depression,and some may require magnetic resonance imaging(MRI)for diagnosis,which can lead to MRI failure due to claustrophobia.AIM To explore the value of psychological interventions in successfully completing functional MRI scans of the brain for PD-related depression.METHODS Ninety-six patients with PD were randomly divided into two groups.The control group(47 patients)received general care,and the experimental group(49 patients)received general care combined with psychological care.The Unified Parkinson's Disease Assessment Scale(UPDRS),Hamilton Depression Scale(HAMD),and Geriatric Depression Scale(GDS)-15 scores,heart rate,systolic blood pressure,and MRI-Anxiety Questionnaire(MRI-AQ)scores before and after the scan were recorded.The completion rate of magnetic resonance(MR)scanning,scanning duration,and image quality scores were recorded.RESULTS Before scanning,no statistically significant difference was observed between the two groups in terms of heart rate,systolic blood pressure,and UPDRS,HAMD,GDS-15,and MRI-AQ scores.After scanning,systolic blood pressure,MRI-AQ score,and scan time in the experimental group were significantly lower than those in the control group,whereas the scan completion rate and image quality score were significantly higher than those in the control group.CONCLUSION Psychological nursing interventions are helpful in alleviating PD-related depression and assessing MR depression scores and may be helpful in the successful completion of functional MRI scans of the patient's brain.

T2* magnetic resonance imaging of the liver in thalassemic patients in Iran

AIM: To investigate the accuracy of T2*-weighted magnetic resonance imaging (MRI T2*) in the evaluation of iron overload in beta-thalassemia major patients. METHODS: In this cross-sectional study, 210 patients with beta-thalassemia major having regular blood transfusions were consecutively enrolled. Serum ferritin levels were measured, and all patients underwent MRI T2* of the liver. Liver biopsy was performed in 53 patients at an interval of no longer than 3 mo after the MRIT2* in each patient. The amount of iron was assessed in both MRI T2* and liver biopsy specimens of each patient. RESULTS: Patients’ ages ranged from 8 to 54 years with a mean of 24.59 ± 8.5 years. Mean serum ferritin level was 1906 ± 1644 ng/mL. Liver biopsy showed a moderate negative correlation with liver MRI T2* (r = -0.573, P = 0.000) and a low positive correlation with ferritin level (r = 0.350, P = 0.001). Serum ferritin levels showed a moderate negative correlation with liver MRI T2* values (r = -0.586, P = 0.000). CONCLUSION: Our study suggests that MRI T2* is a non-invasive, safe and reliable method for detecting iron load in patients with iron overload.

Tri-linear interpolation-based cerebral white matter fiber imaging

Diffusion tensor imaging is a unique method to visualize white matter fibers three-dimensionally, non-invasively and in vivo, and therefore it is an important tool for observing and researching neural regeneration. Different diffusion tensor imaging-based fiber tracking methods have been already investigated, but making the computing faster, fiber tracking longer and smoother and the details shown clearer are needed to be improved for clinical applications. This study proposed a new fiber tracking strategy based on tri-linear interpolation. We selected a patient with acute infarction of the right basal ganglia and designed experiments based on either the tri-linear interpolation algorithm or tensorline algorithm. Fiber tracking in the same regions of interest （genu of the corpus callosum） was performed separately. The validity of the tri-linear interpolation algorithm was verified by quan- titative analysis, and its feasibility in clinical diagnosis was confirmed by the contrast between tracking results and the disease condition of the patient as well as the actual brain anatomy. Statis- tical results showed that the maximum length and average length of the white matter fibers tracked by the tri-linear interpolation algorithm were significantly longer. The tracking images of the fibers indicated that this method can obtain smoother tracked fibers, more obvious orientation and clearer details. Tracking fiber abnormalities are in good agreement with the actual condition of patients, and tracking displayed fibers that passed though the corpus callosum, which was consistent with the anatomical structures of the brain. Therefore, the tri-linear interpolation algorithm can achieve a clear, anatomically correct and reliable tracking result.

Diffusion tensor imaging with multiple diffusion-weighted gradient directions

Diffusion tensor MRI （DT-MRI or DTI） is emerging as an important non-invasive technology for elucidating intemal brain structures. It has recently been utilized to diagnose a series of diseases that affect the integrity of neural systems to provide a basis for neuroregenerative studies. Results from the present study suggested that neural tissue is reconstructed with multiple diffusion-weighted gradient directions DTI, which varies from traditional imaging methods that utilize 6 gradient directions. Simultaneously, the diffusion tensor matrix is obtained by multiple linear regressions from an equation of echo signal intensity. The condition number value and standard deviation of fractional anisotropy for each scheme can be used to evaluate image quality. Results demonstrated that increasing gradient direction to some extent resulted in improved effects. Therefore, the traditional 6 and 15 directions should not be considered optimal scan protocols for clinical DTI application. In a scheme with 20 directions, the condition number and standard deviation of fractional anisotropy of the encoding gradients matrix were significantly reduced, and resulted in more clearly and accurately displayed neural tissue. Results demonstrated that the scheme with 20 diffusion gradient directions provided better accuracy of structural renderings and could be an optimal scan protocol for clinical DTI application.

Changes in brain function and anatomical structure following treatment of hyperbaric oxygen for visual pathway abnormalities in 16 cases Evaluation of functional magnetic resonance imaging combined with diffusion tensor imaging

BACKGROUND： There is a growing research focus on the combination of blood oxygenation level dependent functional magnetic resonance imaging （BOLD-fMRI） and diffusion tensor imaging （DTI） to evaluate visual cortical function and structural changes in the cerebrum, as well as morphological changes to the white matter fiber tracks, after visual pathway lesions. However, the combined application of BOLD-fMRI and DTI in treating of visual pathway abnormalities still requires further studies. OBJECTIVE： To observe and evaluate the effects of hyperbaric oxygen on visual pathway abnormalities, and to evaluate the characteristics of cerebral function and anatomic structural changes by using BOLD-fMRI combined with DTI technique. DESIGN： Case contrast observation. SETTING： Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA. PARTICIPANTS： Sixteen patients （9 males and 7 females, 15-77 years old） with lateral or bilateral visual disorder induced by visual pathway lesions were selected from the Department of Neurology, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from January 2006 to May 2007. These patients comprised the lesion group. Measures of interventional therapy： hyperbaric oxygen of two normal atmospheres for three courses （10 d/course） and routine internal medicine treatment. In addition, 12 healthy subjects of similar sex and age to the lesion group were regarded as the control group. The control group underwent routine ophthalmological and ocular fundus examinations; diagnostic results were normal. The experiment received confirmed consent from the local ethic committee, and all patients provided informed consent. METHODS： BOLD-fMRI and DTI manifestations in the lesion group were observed before and after hyperbaric oxygen intervention, and the results were compared with the control group. The subjects were positioned on their back, and BOLD-fMRI images were collected with the following GRE EPI sequence： TR = 2 000 ms, TE = 40 ms, layer thickness = 5 mm, and 20-layer successive scanning to cover the whole brain. While, DTI images were collected with SE EPI sequence of single excitation： TR=10 000 ms, TE = 112 ms, layer thickness = 4 mm, layer spacing = 0.5 mm, and a 30-layer successive scanning, matrix = 128×128. A diffusion gradient was applied at 13 directions, and one layer without diffusion weighted imaging was collected at b =1 000 s/mm^2. Numbers of activated voxels in cortical-activated regions, and fractional anisotropy in bilateral cerebral optical radiation regions, were calculated. Displacement, continuity, and destruction of fibrous tracts were analyzed. MAIN OUTCOME MEASURES： Results of BOLD-fMRI and DTI examinations. RESULTS： All 16 patients and 12 controls were included in the final analysis. ① Numbers of activated voxels through the use of BOLD-fMRI： prior to hyperbaric oxygen therapy, the number of activated voxels in the bilateral cortex of occipital lobe were significantly less in the lesion group than in the control group （t =3.23, P 〈 0.01）. In addition, the number of activated voxels significantly increased after treatment compared to before treatment （t = 2.46, P 〈 0.05）. ② Fractional anisotropy in optical radiation regions of bilateral cerebrum： fractional anisotropy in the lesion group was significantly less than the control group （t =2.89, P 〈 0.05）. In addition, fractional anisotropy after treatment was significantly higher than before treatment （t = 2.48, P 〈 0.05）. Moreover, fractional anisotropy of optical neuropathy was significantly higher in 6 patients in the lesion group than the occipital lobe optical central lesion （t = 2.35, P 〈 0.05）. CONCLUSION： BOLD-fMRI combined with DTI can indicate the occurrence, development, and therapeutic course of action for optical pathway lesions. The results acquired from these methods can provide information for function and structure, which can provide reliable verification in the treatment of cerebral function.

Common bile duct diameter in an asymptomatic population:A magnetic resonance imaging study

AIM: To measure the common bile duct(CBD) diameter by magnetic resonance cholangiopancreatography(MRCP) in a large asymptomatic population and analyze its some affecting factors.METHODS: This study included 862 asymptomatic subjects who underwent MRCP. The CBD diameter was measured at its widest visible portion on regular endexpiration MRCP for all subjects. Among these 862 subjects, 221 volunteers also underwent end-inspiration MRCP to study the effect of respiration on the CBD diameter. The age, sex, respiration, body length, body weight, body mass index(BMI), portal vein diameter(PVD), length of the extrahepatic duct and CBD, cystic junction radial orientation and location were recorded. The subjects were divided into 7 groups according to age. All of the above factors were compared with the CBD diameter on end-expiration MRCP.RESULTS: Among the 862 subjects, the CBD diameter was 4.13 ± 1.11 mm(range, 1.76-9.45 mm) and was correlated with age(r = 0.484; P < 0.05), with a dilation of 0.033 mm per year. The upper limit of the 95% reference range was 5.95 mm, resulting in a reasonable upper limit of 6 mm for the asymptomatic population. Respiration and other factors, including sex, body length, body weight, BMI, PVD, length of the extrahepatic duct and CBD, cystic junction radia orientation and location, were not related to the CBD diameter.CONCLUSION: We established a reference range for the CBD diameter on MRCP for an asymptomatic population. The CBD diameter is correlated with age. Respiration did not affect the non-dilated CBD diameter.

Observation of activation status of motor-related cortex of patients with acute ischemic stroke through functional magnetic resonance imaging

BACKGROUND： About more than three fourth of patients with stroke have motor dysfunction at different degrees, especially hand motor dysfunction. Functional magnetic resonance imaging （fMRI） provides very reliable visible evidence for studying central mechanism of motor dysfunction after stroke, and has guiding and applicable value for clinical therapy. OBJECTIVE： To observe the activation of motor-related cortex of patients with acute ischemic stroke with functional magnetic resonance imaging, and analyze the relationship between brain function reconstruction and motor restoration after stroke. DESIGN ： A contrast observation SETTING： Medical Imaging Center, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA. PARTICIPANTS ： Nine patients with acute ischemic stroke who suffered from motor dysfunction and received the treatment in the Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA between August and December 2005 were recruited, serving as experimental group. The involved patients including 5 male and 4 female, aged 16 to 87 years, all met the diagnostic criteria of cerebrovascular disease revised by The Fourth National Conference on Cerebrovascular Disease, mainly presenting paralysis in clinic, and underwent fMRI. Another 9 right handed persons matched in age and gender who simultaneously received healthy body examination were recruited, serving as control group. All the subjects were informed of the detected items. METHODS ： ①Muscular strength of patients of the experimental group was evaluated according to Brunnstrom grading muscular strength （Grade Ⅰ -Ⅳ）. ②Passive finger to finger motion was used as the mission （alternate style of quiescence, left hand motion and quiescence, nght hand motion was repeated 3 times, serving as 1 sequence, 20 s per block and 20 s time interval. The whole process of scanning was 260 s）, and subjects of 2 groups were given Bold-fMRI examination with GEl .5T double gradient 16-channel magnetic resonance imaging system. All the data were given off-line management, and fMRI was treated with SPM2 softwere. The activation of passive finger-to-finger motion-related cortex of subjects in 2 groups was observed. ③ Results of fMRI of subjects in 2 groups were compared. The size of activation region of brain and signal intensity were measured and unilateral index was calculated. The data of activation region of cerebral hemisphere of different sides at finger motion were given statistical analysis of unilateral index. Differences among unilateral indexes at hand motion were compared between intact and affected hands of patients in experimental group. The relationship between unilateral index and muscular strength of affected hands at affected hand motion in patients of the experimental group was performed Spearman correlation analysis. MAIN OUTCOME MEASURES： ① The activation of motion-related cortex passive finger-to-finger motion between handedness and non-handedness was detected with functional magnetic resonance imaging of subjects in 2 groups. ②Relationship between unilateral index and muscular strength of subjects of experimental group at affected hand motion. RESULTS： Nine patients with ischemic stroke and 9 controls all participated in the final result analysis. ① Passive fMRI detection results between handedness and non-handedness of controls： Right-handed finger-to-finger motion of subjects of control group mainly activated contralateral sensonmotor cortex, and left-handed finger-to-finger motion not only activated above-mentioned brain region, but also activated supplementary motor area （SMA） of contralateral brain region; ②In the experimental group, sensorimotor cortex of contralateral hemisphere was activated at affected hand motion, and homolateral posterior parietal cortex （PPC）was also obviously activated. Bilateral sensonmotor cortex was activated at affected hand motion in 2 patients, and homolateral activation area was larger than contralateral one. At intact hand motion, contralateral sensorimotor cortex was activated, but no obvious homolateral activation area was found. ③ Correlation of unilateral index with muscular strength： Passive finger-to-finger fMRI （ between affected and intact hands of subjects of experimental group： Unilateral index at passive single finger motion of affected and intact hand of subjects of experimental group was -0.018±0.01 and 0.319±0.187, respectively, with significant difference （t=4.059, P 〈 0.01 ）. Unilateral index was significantly positively correlated with the muscular strength of affected hand at affected hand motion（r=0.834, P 〈 0.05）.CONCLUSION ： ①fMRI can objectively shows different activation states of motor cortex between patients with ischemic stroke and healthy controls, and brain functional compensation and recombination exist. Both primary sensorimotor cortex and SMA of bilateral hemispheres participant in affected hand motion, at the same time, parietal lobe and cortex of intact side also obviously participant in the affected hand motion. ②Correlation analysis of unilateral index and muscular strength of affected hand performed through fMRI can be used as an effective means to investigate the relationship between motion rehabilitation and brain functional recombination after stroke.

Role of MR imaging in the diagnosis of intracranial germinoma

Objective: To investigate the role of MRI in the diagnosis of intracranial germinoma. Methods: MRI features of 19 cases of intracranial germinoma confirmed by operations and pathological findings were analyzed retrospectively. Results: Germinomas were found in the sellar region in 10 patients (including 5 males and 5 females), in the pineal region in 6 and in the thalamus and basal ganglia in 3, the 9 patients in the latter 2 groups all being males. The characteristic MRI findings of intracranial germinomas were as follows: (1) Lesions were isointense or slightly hypointense on T1WI while isointense or slightly hyperintense on T2WI. The germinomas in the sellar region and pineal region showed no edema, but lesions in the thalamus basal ganglia showed mild to moderate edema and space-occupying effects. (2) Homogeneous or inhomogeneous Gd-DTPA enhancement were seen in most of the tumors. Conclusion: Multiaxial imaging and Gd-DTPA enhancement in MRI are helpful in the diagnosis and differentiation of intracranial germinomas on the basis of the patient's gender, the location of the tumor and its imaging characteristics.

A cadaveric breast cancer tissue phantom for phase-contrast X-ray imaging applications

Background:As mammography X-ray imaging technologies advance and provide elevated contrast in soft tissues,a need has developed for reliable imaging phantoms for use in system design and component calibration.In advanced imaging modalities such as refraction-based methods,it is critical that developed phantoms capture the biological details seen in clinical precancerous and cancerous cases while minimizing artifacts that may be caused due to phantom production.This work presents the fabrication of a breast tissue imaging phantom from cadaveric breast tissue suitable for use in both transmission and refraction-enhanced imaging systems.Methods:Human cancer cell tumors were grown orthotopically in nude athymic mice and implanted into the fixed tissue while maintaining the native tumor/adipose tissue interface.Results:The resulting human–murine tissue hybrid phantom was mounted on a clear acrylic housing for absorption and refraction X-ray imaging.Digital breast tomosynthesis was also performed.Conclusion:Both attenuation-based imaging and refraction-based imaging of the phantom are presented to confirm the suitability of this phantom's use in both imaging modalities.

Recent developments of the reconstruction in magnetic particle imaging

Magnetic particle imaging(MPI)is an emerging molecular imaging technique with high sensitivity and temporal-spatial resolution.Image reconstruction is an important research topic in MPI,which converts an induced voltage signal into the image of superparamagnetic iron oxide particles concentration distribution.MPI reconstruction primarily involves system matrix-and x-space-based methods.In this review,we provide a detailed overview of the research status and future research trends of these two methods.In addition,we review the application of deep learning methods in MPI reconstruction and the current open sources of MPI.Finally,research opinions on MPI reconstruction are presented.We hope this review promotes the use of MPI in clinical applications.

SPIO-enhanced magnetic resonance imaging for differentiating metastatic from hyperplastic lymph nodes: A study in rabbits

Objective: To investigate the potential of superparamagnetic iron oxide particles (SPIO) in MR imaging for the differentiation between hyperplastic and metastatic lymph node. Methods: Animal models of malignant lymph node metastasis were established in 6 New-Zealand rabbits by a unilateral intra-muscular injection of VX2 carcinoma cells, and models of hyperplastic lymph nodes were induced in another 6 rabbits by a unilateral intra-muscular injection of egg yolk emulsion. MR images of the lymph nodes were obtained before and 12 h after interstitial injection of SPIO. Image results were analyzed and compared with pathological findings. Results: On unenhanced images, the signal intensity of hyperplastic and metastatic lymph nodes did not differ significantly. After administration of SPIO, the signal intensity of both hyperplastic and metastatic lymph nodes remained unchanged on T1-weighted SE images. On T2-weighted SE images, the signal intensity of hyperplastic lymph nodes decreased heterogeneously, while that of all metastatic ones remained unchanged. On T2-weighted GRE images, the signal intensity of hyperplastic lymph nodes decreased significantly and homogeneously, while that of 4 metastatic ones remained unchanged and that of the rest 2 decreased heterogeneously. Conclusion: SPIO-enhanced MR imaging may enable the differentiation between the hyperplastic and metastatic lymph nodes.

Research progresses of resting-state functional MRI in mild cognitive impairment and Alzheimer's disease

Alzheimer's disease(AD)is a prevalent neurodegenerative disease characterized by cognitive decline in the early stage.Mild cognitive impairment(MCI)is considered as an intermediate stage between normal aging and AD.In recent years,studies related to resting-state functional MRI(rs-fMRI)indicated that the occurrence and development process of MCI and AD might be closely linked to spontaneous brain activity and alterations in functional connectivity among brain regions,and rs-fMRI could provide important reference for specific diagnosis and early treatment of MCI and AD.The research progresses of rs-fMRI for MCI and AD were reviewed in this article.

Deep learning models semi-automatic training system for quality control of transthoracic echocardiography

Objective To explore the value of deep learning(DL)models semi-automatic training system for automatic optimization of clinical image quality control of transthoracic echocardiography(TTE).Methods Totally 1250 TTE videos from 402 patients were retrospectively collected,including 490 apical four chamber(A4C),310 parasternal long axis view of left ventricle(PLAX)and 450 parasternal short axis view of great vessel(PSAX GV).The videos were divided into development set(245 A4C,155 PLAX,225 PSAX GV),semi-automated training set(98 A4C,62 PLAX,90 PSAX GV)and test set(147 A4C,93 PLAX,135 PSAX GV)at the ratio of 5∶2∶3.Based on development set and semi-automatic training set,DL model of quality control was semi-automatically iteratively optimized,and a semi-automatic training system was constructed,then the efficacy of DL models for recognizing TTE views and assessing imaging quality of TTE were verified in test set.Results After optimization,the overall accuracy,precision,recall,and F1 score of DL models for recognizing TTE views in test set improved from 97.33%,97.26%,97.26%and 97.26%to 99.73%,99.65%,99.77%and 99.71%,respectively,while the overall accuracy for assessing A4C,PLAX and PSAX GV TTE as standard views in test set improved from 89.12%,83.87%and 90.37%to 93.20%,90.32%and 93.33%,respectively.Conclusion The developed DL models semi-automatic training system could improve the efficiency of clinical imaging quality control of TTE and increase iteration speed.

Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study

BACKGROUND Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high incidence worldwide.As a common local treatment,RFA has attracted much attention for its efficacy and influence on liver function.AIM To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by RFA.METHODS The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and June 2023 were collected.The chi-square test was used to compare the data between groups.The Kaplan-Meier method and Cox regression were used to analyze the associ-ations between serum ALP and GGT levels and overall survival,progression-free survival(PFS)and clinical characteristics of patients before treatment.RESULTS The 1-year survival rates of patients with normal(≤135 U/L)and abnormal(>135 U/L)serum ALP before treatment were 91%and 79%,respectively;the 2-year survival rates were 90%and 68%,respectively;and the 5-year survival rates were 35%and 18%,respectively.The difference between the two groups was statistically significant(P=0.01).Before treatment,the 1-year survival rates of patients with normal serum GGT levels(≤45 U/L)and abnormal serum GGT levels(>45 U/L)were 95%and 87%,the 2-year survival rates were 85%and 71%,and the 5-year survival rates were 37%and 21%,respectively.The difference between the two groups was statist-ically significant(P<0.001).Serum ALP[hazard ratio(HR)=1.766,95%confidence interval(95%CI):1.068-2.921,P=0.027]and GGT(HR=2.312,95%CI:1.367-3.912,P=0.002)is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic factor.The 1-year PFS rates were 72%and 50%,the 2-year PFS rates were 52%and 21%,and the 5-year PFS rates were 14%and 3%,respectively.The difference between the two groups was statistically significant(P<0001).The 1-year PFS rates were 81%and 56%in patients with normal and abnormal serum GGT levels before treatment,respectively;the 2-year PFS rates were 62%and 35%,respectively;and the 5-year PFS rates were 18%and 7%,respectively,with statistical significance between the two groups(P<0.001).The serum ALP concentration(HR=1.653,95%CI:1.001-2.729,P=0.049)and GGT(HR=1.949,95%CI:1.296-2.930,P=0.001)was closely associated with PFS after RFA in patients with PLC.The proportion of male patients with abnormal ALP levels is high,the Child-Pugh grade of liver function is poor,and the incidence of ascites is high.Among GGT-abnormal patients,the Child-Pugh grade of liver function was poor,the tumor stage was late,the proportion of patients with tumors≥5 cm was high,and the incidence of hepatic encephalopathy was high.CONCLUSION Serum ALP and GGT levels before treatment can be used to predict the prognosis of patients with PLC after RFA,and they have certain guiding significance for the long-term survival of patients with PLC after radiofrequency therapy.

One Case of Right Posterior Mediastinum Intraneural Hemangioma Misdiagnosed as Neurilemmoma

Although rare, intraneural hemangiomas should be considered in the differential diagnosis of peripheral nerve lesions. We report on a 59-year-old female patient, who was admitted to the hospital due to the discovery of bilateral breast masses for 3 months, there was no paresthesia or dyskinesia. The patient accidentally found a mass in the right upper mediastinum while completing a plain chest X-ray, initially suspected as a benign neurilemmoma on CT. Surgical resection and pathological analysis confirmed an intraneural hemangioma. Unexpectedly, the patient developed new-onset right upper limb numbness and paresthesia 3 months post-operatively, probably related to surgical nerve injury. This case underscores the importance of maintaining a broad differential for mediastinal masses, and the potential for iatrogenic neurological complications when managing these rare, yet vascular lesions.

密度指数：形状指数在描述三维图像时的推广

针对将形状指数(SI)应用于三维图像时缺乏对应的推广形式,常通过计算三维图像的3个截面的SI来组合表达,导致在肠道肿瘤检测等应用中造成了大量的误检的问题,研究了三维情形SI的推广.首先选取球坐标系表达的单位球面以消除灰度变化尺度的影响;然后分析了球面的6个等价区域,并选取其一作为灰度变化的表征区域;由于SI原有的表达式不利于推广到三维空间,因此推导了一种等价的表达式,并通过分析此表达式在三维情形的推广,得到了描述三维图像局部灰度变化的指标——密度指数(DI).通过研究DI所表征区域的几何特性,得到了一条具有重要性质的曲线——逆Z线,并分析了其上典型特征点所对应的灰度变化模式.仿真实验结果表明,对于肠道肿瘤检测的典型情况,使用DI检测的误检率明显低于SI.

Application of 3D reconstruction for surgical treatment of hepatic alveolar echinococcosis

AIM: To evaluate the reliability and accuracy of threedimensional(3D) reconstruction for liver resection in patients with hepatic alveolar echinococcosis(HAE).METHODS: One-hundred and six consecutive patients with HAE underwent hepatectomy at our hospital between May 2011 and January 2015. Fifty-nine patients underwent preoperative 3D reconstruction and "virtual" 3D liver resection before surgery(Group A). Another 47 patients used conventional imaging methods for preoperative assessment(Group B). Outcomes of hepatectomy were compared between the two groups.RESULTS: There was no significant difference in preoperative data between the two groups. Compared with patients in Group B, those in Group A had a significantly shorter operation time(227.1 ± 51.4 vs 304.6 ± 88.1 min; P < 0.05), less intraoperative blood loss(308.1 ± 135.4 vs 458.1 ± 175.4 m L; P < 0.05), and lower requirement for intraoperative blood transfusion(186.4 ± 169.6 vs 289.4 ± 199.2 m L; P < 0.05). Estimated resection liver volumes in bothgroups had good correlation with actual graft weight(Group A: r = 0.978; Group B: r = 0.960). There was a significant higher serum level of albumin in Group A(26.3 ± 5.9 vs 22.6 ± 4.3 g/L, P < 0.05). Other postoperative laboratory parameters(serum levels of aminotransferase and bilirubin; prothrombin time) and duration of postoperative hospital stay were similar. Sixteen complications occurred in Group A and 19 in Group B. All patients were followed for 3-46(mean, 17.3) mo. There was no recurrence of lesions in Group A, but two recurrences in Group B. There were three deaths: two from cerebrovascular accident, and one from car accident.CONCLUSION: 3D reconstruction provides comprehensive and precise anatomical information for the liver. It also improves the chance of success and reduces the risk of hepatectomy in HAE.

Diagnostic value of two dimensional shear wave elastography combined with texture analysis in early liver fibrosis

BACKGROUND Staging diagnosis of liver fibrosis is a prerequisite for timely diagnosis and therapy in patients with chronic hepatitis B.In recent years,ultrasound elastography has become an important method for clinical noninvasive assessment of liver fibrosis stage,but its diagnostic value for early liver fibrosis still needs to be further improved.In this study,the texture analysis was carried out on the basis of two dimensional shear wave elastography(2D-SWE),and the feasibility of 2D-SWE plus texture analysis in the diagnosis of early liver fibrosis was discussed.AIM To assess the diagnostic value of 2D-SWE combined with textural analysis in liver fibrosis staging.METHODS This study recruited 46 patients with chronic hepatitis B.Patients underwent 2DSWE and texture analysis;Young's modulus values and textural patterns were obtained,respectively.Textural pattern was analyzed with regard to contrast,correlation,angular second moment(ASM),and homogeneity.Pathological results of biopsy specimens were the gold standard;comparison and assessment of the diagnosis efficiency were conducted for 2D-SWE,texture analysis and their combination.RESULTS 2D-SWE displayed diagnosis efficiency in early fibrosis,significant fibrosis,severe fibrosis,and early cirrhosis(AUC>0.7,P<0.05)with respective AUC values of 0.823(0.678-0.921),0.808(0.662-0.911),0.920(0.798-0.980),and 0.855(0.716-0.943).Contrast and homogeneity displayed independent diagnosis efficiency in liver fibrosis stage(AUC>0.7,P<0.05),whereas correlation and ASM showed limited values.AUC of contrast and homogeneity were respectively 0.906(0.779-0.973),0.835(0.693-0.930),0.807(0.660-0.910)and 0.925(0.805-0.983),0.789(0.639-0.897),0.736(0.582-0.858),0.705(0.549-0.883)and 0.798(0.650-0.904)in four liver fibrosis stages,which exhibited equivalence to 2D-SWE in diagnostic efficiency(P>0.05).Combined diagnosis(PRE)displayed diagnostic efficiency(AUC>0.7,P<0.01)for all fibrosis stages with respective AUC of 0.952(0.841-0.994),0.896(0.766-0.967),0.978(0.881-0.999),0.947(0.835-0.992).The combined diagnosis showed higher diagnosis efficiency over 2D-SWE in early liver fibrosis(P<0.05),whereas no significant differences were observed in other comparisons(P>0.05).CONCLUSION Texture analysis was capable of diagnosing liver fibrosis stage,combined diagnosis had obvious advantages in early liver fibrosis,liver fibrosis stage might be related to the hepatic tissue hardness distribution.

Acupuncture inhibits cue-induced heroin craving and brain activation

Previous research using functional MRI has shown that specific brain regions associated with drug dependence and cue-elicited heroin craving are activated by environmental cues. Craving is an important trigger of heroin relapse, and acupuncture may inhibit craving. In this study, we performed functional MRI in heroin addicts and control subjects. We compared differences in brain activation between the two groups during heroin cue exposure, heroin cue exposure plus acupuncture at the Zusanli point （ST36） without twirling of the needle, and heroin cue exposure plus acupuncture at the Zusanli point with twirling of the needle. Heroin cue exposure elicited significant activation in craving-related brain regions mainly in the frontal lobes and callosal gyri. Acupuncture without twirling did not significantly affect the range of brain activation induced by heroin cue exposure, but significantly changed the extent of the activation in the heroin addicts group. Acupuncture at the Zusanli point with twirling of the needle significantly decreased both the range and extent of activation induced by heroin cue exposure compared with heroin cue exposure plus acupuncture without twirling of the needle. These experimental findings indicate that presentation of heroin cues can induce activation in craving-related brain regions, which are involved in reward, learning and memory, cognition and emotion. Acupuncture at the Zusanli point can rapidly suppress the activation of specific brain regions related to craving, supporting its potential as an intervention for drug craving.