Endoscopicultrasonographyforsurveillanceofindividualsathighriskfor pancreaticcancer

Pancreatic cancer is a highly lethal disease with a ge-netic susceptibility and familial aggregation found in 3%-16% of patients. Early diagnosis remains the only hope for curative treatment and improvement of prog-nosis. This can be reached by the implementation of an intensive screening program, actually recommended for individuals at high-risk for pancreatic cancer de-velopment. The aim of this strategy is to identify pre-malignant precursors or asymptomatic pancreatic can-cer lesions, curable by surgery. Endoscopic ultrasound (EUS) with or without fine needle aspiration(FNA) seems to be the most promising technique for early de-tection of pancreatic cancer. It has been described as a highly sensitive and accurate tool, especially for small and cystic lesions. Pancreatic intraepithelial neoplasia, a precursor lesion which is highly represented in high-risk individuals, seems to have characteristics chronic pancreatitis-like changes well detected by EUS. Many screening protocols have demonstrated high diagnostic yields for pancreatic pre-malignant lesions, allowing prophylactic pancreatectomies. However, it shows a high interobserver variety even among experienced en-dosonographers and a low sensitivity in case of chronic pancreatitis. Some new techniques such as contrast-en-hanced harmonic EUS, computer-aided diagnostic tech-niques, confocal laser endomicroscopy miniprobe andthe detection of DNA abnormalities or protein markersby FNA, promise improvement of the diagnostic yield ofEUS. As the resolution of imaging improves and as ourknowledge of precursor lesions grows, we believe thatEUS could become the most suitable method to detectcurable pancreatic neoplasms in correctly identifiedasymptomatic at-risk patients.

Liver cell cancer surveillance practice in Nigeria:Pitfalls and future prospects

Hepatocellular carcinoma(HCC)is a disease of public health concern in Nigeria,with chronic hepatitis B and C infections contributing most to the disease burden.Despite the increasing incidence of HCC,surveillance practices for early diagnosis and possible cure are not deeply rooted in the country.This article aims to review the current status of HCC surveillance in Nigeria,stressing the encounters,breaches,and potential prospects.Several factors,such as limited tools for screening and diagnostics,insufficient infrastructure,and low cognizance among the doctors,and the general public affect the surveillance practices for HCC in Nigeria.Moreover,the lack of standardized guidelines and protocols for HCC surveillance further intensifies the suboptimal diagnosis and treatment.Nevertheless,there are opportunities for refining surveillance practices in the country.This would be achieved through boosted public health sensitization campaigns,integrating HCC screening into routine clinical services,and leveraging technological developments for early detection and monitoring.Furthermore,collaboration between government agencies,healthcare providers,and international organizations can facilitate the development of comprehensive HCC surveillance programs person-alized to the Nigerian setting.Thus,HCC surveillance practice faces substantial challenges.By addressing the drawbacks and leveraging prospects,Nigeria can improve HCC surveillance,with subsequent improved outcomes for individuals at risk of developing the disease.

Surveillance for early diagnosis of hepatocellular carcinoma: How best to do it?

Surveillance for hepatocellular carcinoma(HCC)is considered a standard of care for patients with chronic liver disease who are at risk of developing this malignancy.Several studies have shown that surveillance can improve the prognosis of patients diagnosed with HCC through an increased likelihood of application of curative or effective treatments.Repetition of liver ultrasonography(US)every 6 mo is the recommended surveillance program to detect early HCCs,and a positive US has to entrain a well-defined recall policy based on contrast-enhanced,dynamic radiological imaging or biopsy for the diagnosis of HCC.Although HCC fulfills the accepted criteria regarding cost-effective cancer screening and surveillance,the implementation of surveillance in clinical practice is defective and this has a negative impact on the cost-effectiveness of the procedure.Education of both physicians and patients is of paramount importance in order to improve the surveillance application and its benefits in patients at risk of HCC.The promotion of specific educational programs for practitioners,clinicians and patients is instrumental in order to expand the correct use of surveillance in clinical practice and eventually improve HCC prognosis.

Surveillance and diagnosis of hepatocellular carcinoma: A systematic review

BACKGROUND Hepatocellular carcinoma (HCC) appears in most of cases in patients with advanced liver disease and is currently the primary cause of death in this population.Surveillance of HCC has been proposed and recommended in clinical guidelines to obtain earlier diagnosis,but it is still controversial and is not accepted worldwide.AIM To review the actual evidence to support the surveillance programs in patients with cirrhosis as well as the diagnosis procedure.METHODS Systematic review of recent literature of surveillance (tools,interval,cost-benefit,target population) and the role of imaging diagnosis (radiological non-invasive diagnosis,optimal modality and agents) of HCC.RESULTS The benefits of surveillance of HCC,mainly with ultrasonography,have been assessed in several prospective and retrospective analysis,although the percentage of patients diagnosed in surveillance programs is still low.Surveillance of HCC permits diagnosis in early stages allows better access to curative treatment and increases life expectancy in patients with cirrhosis.HCC is a tumor with special radiological characteristics in computed tomography and magnetic resonance imaging,which allows highly accurate diagnosis without routine biopsy confirmation.The actual recommendation is to perform biopsy only in indeterminate nodules.CONCLUSION The evidence supports the recommendation of performing surveillance of HCC in patients with cirrhosis susceptible of treatment,using ultrasonography every 6 mo.The diagnosis evaluation of HCC can be established based on noninvasive imaging criteria in patients with cirrhosis.

A COMPARATIVE STUDY OF TRANSVAGINAL ULTRASONOGRAPHY AND PELVIC ARTERIOGRAM IN ASSESSMENT OF PATIENTS WITH GESTATIONAL TROPHOBLASTIC TUMOUR

Objective:To compare the reliability of transvaginal ultrasonography with pelvic arteriography in the assessment of patients with gestational trophoblastic disease. Methods. Transvaginal ultrasonography was performed in 24 patients with gestational trophoblastic tumour. Within one week after ultrasound investigation, pelvic arteriography was carried out in each patient. Of 24 cases, 16 patients hadn’t been treated by chemical reagent, 5 had accepted 2 to 5 courses of chemotherapy, and 3 had achieved complete remission before both investigations performed. Results. In 3 patients with complete remission, 2 had no evidence of abnormal findings either on transvaginal ultrasonography or on pelvic arteriography, 1 showed intramyometrial lesions by both methods. In the remaining 21 patients, all demostrated a abnormal uterine image, and 5 of them accompanied with the finding of parametrium metastatic signs by transvaginal ultrasonography; these abnormal results were confirmed by pelvic arteriographic imaging. However, in two cases without clinical and ultrasonic signs of parametrium metastasis, pelvic arteriography indicated the early metastasis of parametrium ves- sels. Conclusions. Even though it is difficult to predict the early parametrium metastasis in patients with gestational trophoblastic disease by B-ultrasonic investigation, our data would support the introduction of transvaginal ultrasonography in the diagnosis and evaluation of gestational trophoblastic tumour.

探讨经腹部超声引导宫腔管置入在不同分期宫颈癌患者三维腔内近距离放射治疗中的应用价值分析

目的:探讨经腹部超声(TAUS)引导宫腔管置入在ⅠB1~ⅣB期宫颈癌患者三维腔内近距离放射治疗(3D-ICB)中的临床应用及价值。方法:选取2023年6月—12月在贵州省人民医院收治的48例宫颈癌患者为研究对象,按宫腔管置入方法分为常规置入组(24例)和TAUS组(24例),每组均进行120次近距离放射治疗,经CT定位扫描验证两组患者的子宫隐匿穿孔率。结果:TAUS组与常规置入组比较,操作时长缩短(18.71 min vs 13.09 min,P=0.001),术中出血比例下降(19.16%vs 15.83%,P=0.611),CT扫描次数减少(121次vs 132次),隐匿性穿孔率下降(0.83%vs 5.83%,P=0.031),其中TAUS组与常规置入组各个分期穿孔率比较:ⅠB1~ⅡA2期(0.00%vs 0.00%);ⅡB~ⅢB期(0.00%vs 2.20%,P=0.343);ⅢC~ⅣB期(1.54%vs 10.00%,P=0.040)。结论:TAUS引导可以减少不同分期宫颈癌患者在3D-ICB宫腔管置入术中的时长,同时降低ⅢC~ⅣB期宫颈癌患者术后隐匿性穿孔率,为宫颈癌患者尤其是晚期患者的3D-ICB提供了一个更加安全有效的方法。

Ultrasonography of Hepatocellular Carcinoma:From Diagnosis to Prognosis

Hepatocellular carcinoma(HCC)is a prominent contributor to cancer-related mortality worldwide.Early detection and diagnosis of liver cancer can significantly improve its prognosis and patient survival.Ultrasound technology,serving has undergone substantial advances as the primary method of HCC surveillance and has broadened its scope in recent years for effective management of HCC.This article is a comprehensive overview of ultrasound technology in the treatment of HCC,encompassing early detection,diagnosis,staging,treatment evaluation,and prognostic assessment.In addition,the authors summarized the application of contrast-enhanced ultrasound in the diagnosis of HCC and assessment of prognosis.Finally,the authors discussed further directions in this field by emphasizing overcoming existing obstacles and integrating cutting-edge technologies.

纵隔子宫患者妊娠晚期剖宫产母儿结局分析

目的:分析妊娠晚期行剖宫产术的纵隔子宫患者的母儿结局情况。方法:收集于华中科技大学同济医学院附属同济医院行剖宫产术的≥34周的纵隔子宫孕妇80例作为研究组,选取同期≥34周行剖宫产的正常子宫孕妇80例作为对照组。比较2组孕妇的一般情况、胎盘和胎儿情况、术中出血量和新生儿情况。结果:2组孕妇年龄、孕次、产前体质量、辅助生殖技术助孕、母体合并症、胎盘异常情况、胎膜早破、脐带绕颈2周及以上、术中出血量、新生儿窒息和低出生体质量儿等方面比较,差异无统计学意义(均P>0.05),纵隔子宫组孕妇既往产次、终止妊娠孕周和新生儿出生体质量低于对照组,胎儿臀位比例高于对照组,差异有统计学意义(均P<0.05)。结论:≥34周的纵隔子宫孕妇常常合并胎方位的临床问题,适时终止妊娠并适当采取剖宫产术,母儿结局与子宫正常孕妇相似。

Diagnosing early scar pregnancy in the lower uterine segment after cesarean section by intracavitary ultrasound

BACKGROUND Early scar pregnancy(CSP)in the lower uterine segment after cesarean section is a type of ectopic pregnancy that can cause major complications if left untreated.Transabdominal ultrasound is a common procedure but is influenced by external factors.Thus,intracavitary ultrasound may have better diagnostic efficiency for CSP.AIM To assess the value of intracavitary ultrasound for diagnosing CSP in the lower uterine segment after cesarean section.METHODS Patients diagnosed with CSP in our hospital from October 2019 to April 2021 were recruited.Transabdominal and intracavitary ultrasound examinations were performed to compare the diagnostic differences for CSP and its types.RESULTS Sixty-three patients were diagnosed during the study period.The diagnostic accuracy for CSP was higher in intracavitary ultrasound(96.83%)than in transabdominal ultrasound(84.13%)(P<0.05).The missed diagnosis and misdiagnosis rates did not differ among the ultrasound types(intra:0.00%and 3.17%;trans:4.76%and 11.11%,respectively;P>0.05).For the diagnostic rates for the CSP types,the rates for gestational sac(100.00%vs 90.48%),heterogeneous mass(93.75%vs 75.00%),and part of the uterine cavity(80.00%vs 60.00%)were higher in intracavitary ultrasound than in transabdominal ultrasound,but the difference was not statistically significant(P>0.05).For gestational sac CSP patients,intracavitary ultrasound showed that the gestational sac was located in the lower uterine segment scar with abundant peripheral blood flow;the distance between the gestational sac and the serosal layer was 2.42±0.50 cm.Intracavitary ultrasound for heterogeneous mass CSP patients indicated that the mass mainly occurred in the lower anterior uterine wall,protruding into the bladder,and was surrounded by abundant internal and peripheral blood flow;the distance between the mass and serosal layer was 1.79±0.30 cm.For CSP type partly located in the uterine cavity,the gestational sac was partly located in the lower uterine cavity and partly in the scar with abundant internal and peripheral blood flow;the distance between the gestational sac and the serosal layer was 2.29±0.28 cm.CONCLUSION Intracavitary ultrasound had a higher diagnostic accuracy and application value for diagnosing CSP than transabdominal ultrasound,with reduced risk of missed diagnoses and misdiagnosis,thereby preventing delayed treatment.

超声检测子宫内膜容受性在单角子宫妊娠结局评估中的价值

目的探讨超声检测子宫内膜容受性在单角子宫妊娠结局评估中的价值。方法回顾性分析2011年1月—2021年5月收治的单角子宫妊娠46例临床资料,患者均行阴道超声检查,比较不同子宫内膜容受性分型患者超声参数。以子宫内膜容受性A、B型作为妊娠成功的预测指标,C型作为妊娠失败的预测指标,以实际妊娠结局作为金标准,计算超声检测子宫内膜容受性预测妊娠结局的敏感度、特异度、阳性预测值、阴性预测值、准确度和Kappa值。结果46例中子宫内膜容受性A型17例(36.96%),B型22例(47.83%),C型7例(15.22%)。不同子宫内膜容受性分型患者子宫内膜厚度、收缩期血流峰值/舒张末期血流速度、搏动指数、阻力指数比较差异均无统计学意义(P>0.05)。子宫内膜容受性分型A型患者妊娠成功率明显高于C型(P<0.05),但A型与B型、B型与C型患者妊娠成功率比较差异均无统计学意义(P>0.05)。超声检测子宫内膜容受性对单角子宫妊娠结局的预测敏感度、特异度、阳性预测值、阴性预测值、准确度和Kappa值分别为96.55%、35.29%、71.79%、85.71%、73.91%、0.36。结论超声检测子宫内膜容受性预测单角子宫妊娠结局的价值较高,并可为单角子宫妊娠患者的诊治提供重要的指导作用。

超声诊断单角子宫合并残角子宫伴左输卵管妊娠1例

患者女,30岁,停经57天、反复阴道出血伴腹痛1周;既往孕1产0,月经规律,半年前因“左输卵管妊娠”接受药物流产。查体:左附件区触及约3cm×2cm包块,伴轻压痛。实验室检查:血人绒毛膜促性腺激素β亚单位测定942.3mIU/ml。经腹联合阴道超声:子宫偏小,未见右侧宫角(图1A);右侧宫腔内见3.5cm×1.7cm低回声团,边界清晰,其内无明显内膜回声(图1B);宫内未见妊娠囊回声;左附件区见4.5cm×3.9cm混合回声包块,边界不清,形态尚规则,CDFI于其内见线状血流信号,周边见环状血流信号(图1C)。

基于超声检查与血脂相关指标构建子宫肌瘤发病的预测模型及其价值验证

目的基于超声检查与血脂相关指标构建子宫肌瘤发病的预测模型,并对其预测价值进行验证。方法选取女性体检者6333例,统计子宫肌瘤发病情况,根据是否发生子宫肌瘤分为观察组与对照组,比较2组临床资料、超声检查指标[超声特征、子宫动脉收缩期峰值血流速度(peak systolic velocit,PSV)、血流阻力指数(resistance index,RI)、搏动指数(pulsation index,PI)]、血脂相关指标[三酰甘油(triglyceride,TG)、高密度脂蛋白胆固醇(high-density lipoprotein cholesterol,HDL-C)、低密度脂蛋白胆固醇(low density lipoprotein cholestero,LDL-C)、总胆固醇(total cholesterol,TC)、血浆致动脉硬化指数(atherogenic index of plasma,AIP)、三酰甘油-葡萄糖指数(triglyceride glucose index,TyG)],构建列线图预测模型,并进行验证。结果经选取标准筛选后,共纳入女性体检者4812例作为入组对象,超声诊断发生子宫肌瘤1065例,子宫肌瘤发病率为22.13%,其中肌壁间肌瘤854例,占80.19%,浆膜下肌瘤156例,占14.65%,黏膜下肌瘤55例,占5.16%;平均子宫肌瘤数目(4.18±1.02)个,平均最大肌瘤直径(6.64±1.89)cm。观察组子宫动脉PSV、PI高于对照组,RI低于对照组(P<0.05);2组HDL-C水平差异无统计学意义(P>0.05),TG、LDL-C、TC、AIP、TyG水平高于对照组(P<0.05);Logistic回归分析,子宫动脉PSV、RI、PI、TG、LDL-C、TC、AIP、TyG是子宫肌瘤发病的独立影响因素(P<0.05);根据上述超声与血脂相关指标构建子宫肌瘤发病的列线图预测模型,校准曲线显示,该预测模型一致性指数为0.827,具有较好的一致性;Hosmer-Lemeshow拟合优度检验显示,P=0.710>0.05,该预测模型拟合度较好;受试者工作特征曲线(receiver operating characteristic,ROC)分析,该预测模型预测子宫肌瘤发病的曲线下面积(area under curve,AUC)为0.912(95%CI:0.837~0.994),敏感度为92.02%,特异度为90.74%。结论基于超声检查参数子宫动脉PSV、RI、PI与血脂指标TG、LDL-C、TC、AIP、TyG构建子宫肌瘤发病预测模型具有可行性,且预测价值较为可靠。

术前误诊为浆膜下子宫肌瘤的卵巢纤维瘤临床误诊分析

目的探讨卵巢纤维瘤术前误诊为浆膜下子宫肌瘤的原因及防范措施。方法对2019年4月—2021年5月收治的术前一度误诊为浆膜下子宫肌瘤的卵巢纤维瘤10例的临床资料进行回顾性分析。结果本组均体检发现左侧单发盆腔肿物,5例出现下腹痛及坠胀感,3例出现腰痛,2例出现尿频、尿急,伴阴道不规则出血3例。超声检查皆于子宫左上方探及一均质团块状低回声。初步诊断为浆膜下子宫肌瘤,行手术治疗,经术后病理结合临床确诊为卵巢纤维瘤。误诊时间1~2 d。10例均行全子宫双附件切除,术后切口愈合后出院。结论临床上无腹腔积液且以盆腔肿物、下腹坠胀、阴道不规则出血、肿瘤压迫症状就诊,超声检查亦不能明确肿瘤来源的卵巢纤维瘤患者,术前极易误诊为子宫肌瘤。加强对该病认识,及早行阴道彩色多普勒超声检查,必要时行手术病理检查,可减少或避免该病误诊误治。

超声自动全容积扫查系统测量晚孕期瘢痕子宫前壁下段肌层厚度

目的通过与传统二维高频超声及术中超声的对比,探讨超声自动全容积扫查系统(AVSS)预测瘢痕子宫前壁下段肌层厚度的价值。方法对24名预行剖宫产的晚孕期瘢痕子宫孕妇,于手术前一天分别进行AVSS成像及二维高频超声(2DHF)扫查,记录图像并分别测量子宫前壁下段肌层厚度;次日,将术中高频超声直接放置于子宫瘢痕区域测量肌壁厚度,并与术前AVSS及2DHF结果对比分析。结果 AVSS系统可以显示孕妇腹壁下段的皮肤、皮下脂肪及腹直肌结构;同时可以清晰显示子宫浆膜层、肌层与黏膜层的结构关系。AVSS的测值与术中超声测值呈正相关(r=0.76,P<0.01),与术中超声的测量差值集中在≤0.5mm范围内。结论 AVSS测量晚孕期瘢痕子宫前壁下段肌层厚度重复性好,其测值更接近术中实际厚度。

超声诊断子宫动静脉瘘

目的探讨子宫动静脉瘘的超声表现及鉴别诊断。方法回顾性分析12例子宫动静脉瘘的超声表现,并与子宫动脉造影相对照。结果子宫动静脉瘘超声表现为近内膜处子宫肌壁或剖宫产切口处肌壁回声不均匀,可见不规则无回声区,典型者呈"蜂窝样"改变,CDFI显示局部区域血流异常丰富,呈"湖泊样"或"五彩镶嵌样"改变,频谱多普勒表现为高速低阻的血流频谱。子宫动脉造影结果与超声检查结果一致。结论超声结合子宫动脉造影有助于确诊子宫动静脉瘘。

阴道超声在腹腔镜多发子宫肌瘤剔除术中的应用价值

目的探讨在腹腔镜剔除子宫多发肌瘤术中应用阴道超声减少肌瘤残留及降低复发的临床价值。方法2010年1月一2011年12月85例多发子宫肌瘤按入院日期单、双号分为阴道超声引导腹腔镜组（n=42）与腹腔镜组（n=43）。阴道超声引导腹腔镜组于腹腔镜手术后经阴道超声引导将残留的子宫肌瘤继续在腔镜下剔除。结果2组术中出血量、术后排气时间、术后住院时间无统计学差异（P〉0．05）。阴道超声引导腹腔镜组术中发现11枚残留肌瘤，均为肌壁间肌瘤，肌瘤直径1．5—2．5cm。腹腔镜组7例复发（16．3％，7／43），阴道超声引导腹腔镜组1例复发（2．4％，1／42），均为肌壁间肌瘤，2组复发率比较无统计学差异（x2=3．321，P=0．068）。结论阴道超声引导下腹腔镜子宫肌瘤剔除术可以最大限度地避免肌瘤残留。

妊娠晚期子宫下段瘢痕高频超声影像学特征及意义

目的应用高频超声检查妊娠晚期子宫下段瘢痕,为妊娠分娩方式的选择提供参考。方法 118例剖宫产后再次妊娠患者,在妊娠36～40周,经腹超声检查胎儿后,换用频率7.5～12 MHz的高频探头,观察子宫下段瘢痕的高频超声表现特征,并与再次剖宫产时术中子宫下段不全破裂及瘢痕愈合不良等情况进行分析比较。结果妊娠晚期子宫下段瘢痕的高频超声表现特征分为"截断状"(6.8%,8/118)、"鼠尾状"(44.1%,52/118)、"均匀一致"(49.1%,58/118)3种类型。"截断状"型诊断不全破裂、"鼠尾状"型诊断瘢痕愈合不良、"均匀一致"型诊断瘢痕愈合正常的符合率均分别高于其他两型(χ2值分别为20.42、19.03、33.08,P均<0.001)。以"截断状"型诊断不全破裂、"鼠尾状"型诊断瘢痕愈合不良、"均匀一致"型诊断瘢痕愈合正常的敏感性、特异性、阳性预测值、阴性预测值分别为80.0%、96.5%、50%、99.0%,70.0%、73.8%、67.3%、76.2%,72.9%、74.6%、74.1%、73.3%。结论高频超声能显示妊娠晚期子宫下段瘢痕的变化,是判断子宫下段不全破裂、瘢痕愈合不良、瘢痕愈合正常的有效方法。为避免子宫破裂的发生,高频超声显示为"截断状"和"鼠尾状"的患者,应慎重选择阴道试产。

静脉内平滑肌瘤病超声误诊分析

目的观察静脉内平滑肌瘤病(IVL)的超声声像图特点。方法分析7例IVL患者的超声声像图特点,与组织学特征和临床发病特点对照,分析超声误诊原因。结果7例IVL患者中位年龄40岁,5例患者曾接受子宫全切手术,平均复发间期13.8个月。7例IVL伴血管内生长,3例延伸至右心房,3例蔓延至下腔静脉,1例局限于盆腔静脉内。7例IVL声像图特征:子宫实性病灶伴血管内病变;子宫切除术后盆腔实性占位伴血管内病变;子宫切除术后盆腔、腹部大血管及心腔内占位病变。主要误诊原因:声像图特征与子宫肌瘤相似,难以鉴别;IVL发病率低,认识不足;影像学检查难以发现早期血管内病灶。结论超声对IVL有较好的临床应用价值,是IVL术后随访的首选影像学方式,检查时应该特别注意病灶与静脉的关系。

不完全纵隔子宫早期妊娠42例的超声声像图临床分析

目的通过对42例不完全纵隔子宫早期妊娠的声像图分析,探讨不完全纵隔子宫早期妊娠的超声诊断与鉴别诊断。方法选择重庆医科大学附属大学城医院2012年9月至2015年9月的超声诊断和(或)临床妇产科诊断为不完全性纵隔子宫妊娠42例,对其早期妊娠(<14周)超声声像图进行观察和分析,总结不完全纵隔子宫妊娠早期的超声声像图特征及其鉴别诊断要点。结果 42例孕妇平均年龄28.5岁,其中超声诊断不完全纵隔子宫妊娠39例,临床证实为不完全纵隔子宫妊娠35例,超声诊断不完全纵隔子宫妊娠正确率83.33%(35/42),假阳性4例,假阳性率9.52%,其中3例为过早宫内妊娠,1例经手术及病理证实为宫角妊娠;假阴性3例,假阴性率7.15%,其中2例被超声诊断为可疑宫内早孕,1例被诊断为宫角妊娠。结论超声对不完全纵隔子宫早期妊娠的声像图表现具有一定特异性,能准确诊断并更好地指导临床。