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91.
Fetal growth restriction   总被引:1,自引:0,他引:1  
Normal fetal growth is determined by the genetically predetermined growth potential and further modulated by maternal, fetal, placental, and external factors. Fetal growth restriction (FGR) is a failure to reach this potential and is clinically suspected if sonographic estimates of fetal weight, size, or symmetry are abnormal. Integration of fetal anatomy assessment, amniotic fluid dynamics, uterine, umbilical, and fetal middle cerebral artery Doppler is the most effective approach to differentiate potentially manageable placenta-based FGR from aneuploidy, nonaneuploid syndromes, and viral infection. Although placental dysfunction results in a multisystem fetal syndrome with impacts on short- and long-term outcome, only cardiovascular and behavioral responses are helpful to guide surveillance and intervention. Early-onset FGR before 34 weeks gestation is readily recognized but challenging to manage as questions about optimal delivery timing remain unanswered. In contrast, near-term FGR provides less of a management challenge but is often missed as clinical findings are more subtle. Once placenta-based FGR is diagnosed, integrating multivessel Doppler and biophysical profile score provides information on longitudinal progression of placental dysfunction and degree of fetal acidemia, respectively. Choosing appropriate monitoring intervals based on anticipated disease acceleration and intervention when fetal risks exceed neonatal risks are the prevailing current management approaches.  相似文献   
92.
Background High intensity focused ultrasound (HIFU) is a novel method which offers the non-invasive ablation of tissues without harming overlying organs or skin. It has been introduced successfully in urology for the ablation of prostatic hyperplasia and seems to be promising in the treatment of uterine fibroids. In this study we aimed to examine the feasibility and possible side effects of HIFU treatment of uterine tissues using an experimental mobile HIFU unit with ultrasound guidance. Methods For these experiments, a 1.07 MHz ultrasound source was used which allows treatment depths between 0 and 10 cm. In 12 patients scheduled to have abdominal hysterectomy, 5–60 impulses of HIFU were applied through the intact skin upon uterine tissues directly prior to the surgical procedure. Tissue intensities lay between 3,200 and 6,300 W/cm2 and a fixed pulse length of 4 s was used. Results No side effects were encountered other than one first-degree skin burn and the treatment was well tolerated. Histology showed clearly demarcated coagulative necrosis in the targeted tissues. Treatment was concluded in less than 45 min for each patient. Conclusion Focused ultrasound is an effective method to selectively destroy tissue within the uterus and the transabdominal access route is very feasible. This study shows that a mobile ultrasound source can be used safely and effectively to destroy uterine tissues, such as fibroids, without major side effects.  相似文献   
93.
Objective  To develop and validate a pictorial chart that documents ultrasound examination of the anal sphincter.
Design  A new pictorial chart (Liverpool Ultrasound Pictorial Chart [LUPIC]) depicting the normal anatomy of the anal sphincter was developed.
Methods  To validate LUPIC, two observers documented the findings of 296 endoanal scans. Reliability was assessed between observers using kappa agreement for presence and position of sphincter defects. To validate the use of LUPIC by different observers, a video of ten endoanal ultrasound scans was reviewed by our local expert (gold standard). Seven clinicians underwent test-retest analysis. Kappa agreement was calculated to assess intra-observer and gold standard versus observer agreement for the overall presence of sphincter defects and compared with the gold standard. Complete agreement for the position and level of sphincter defects was assessed for the five abnormal scans.
Main outcome measures  Excellent agreement between the two observers was found for the presence (kappa 0.99), position and level of external anal sphincter defects documented using LUPIC. The intra-observer and gold standard versus observer kappa values of experienced clinicians (A–E) showed good agreement for the overall presence of sphincter defects. Complete agreement for the position and level of sphincter defects was found in 23 of 35 (66%) observations.
Conclusions  LUPIC is designed and validated method of documenting anal sphincter injury diagnosed by endoanal ultrasound. Standardisation of endoanal ultrasound findings by using LUPIC may help correlate the degree of damage with patient symptoms.  相似文献   
94.
Objective  To evaluate the outcome of severely anaemic monochorionic (MC) twins surviving the death of their co-twin following early intrauterine rescue transfusion in cases of feto-fetal transfusion syndrome (FFTS).
Study design  We reviewed all MC pregnancies complicated with FFTS following primary management, in which a single intrauterine fetal death (IUFD) was diagnosed with certainty within 24 hours between January 1999 and December 2006. We included MC survivors who presented ultrasound or Doppler features of fetal anaemia following the death of their co-twin. Intrauterine transfusion (IUT) was given to all survivors who were anaemic.
Results  Nineteen MC twin pregnancies presented a single intrauterine death (IUD) associated with an anaemic co-twin. Median gestational age at IUD was 23 [20–28] weeks. The median interval between IUD and IUT was 12 [8–24] hours. There were 58% (11/19) healthy survivors. Perinatal death rate was 26% (5/19) including 16% (3/19) intrauterine and 10% (2/19) neonatal deaths. Abnormal prenatal cerebral findings developed in 21% (4/19) cases, always within 1 month after the death of the co-twin. Considering occlusive techniques and other management separately, there were 64% (7/11) and 50% (4/8) healthy survivors, respectively, and perinatal death occurred in 36% (4/11) and 12.5% (1/8) of fetuses, respectively. Prenatal fetal cerebral lesions developed in 9% (1/11) of cases following occlusive techniques and in 37.5% (3/8) of fetuses when managed differently. The median gestational age at delivery in the survivors was 31 [25–38] weeks.
Conclusion  In cases of FFTS with single anaemic survivors, early IUT could be offered following extensive counselling and close follow up.  相似文献   
95.
96.
Transvaginal ultrasound with an empty bladder is recommended as a standardised ultrasonic technique for the accurate diagnosis of the retroverted uterus. Using this method, the prevalence of the retroverted uterus in 480 general gynaecological patients attending for subspecialist gynaecological ultrasound was 18%. The anteverting effect of the full bladder required for transabdominal ultrasound reduces the prevalence of the retroverted uterus to 13% (P < 0.001).  相似文献   
97.
Real-time ultrasound is a dynamic imaging technique that allows in utero orientation to the fetus. It permits rapid and efficient examination of fetal anatomy and provides a dynamic assessment of fetal well-being. The energy dissipation can be comparable to that in conventional ultrasonic B-mode scanning. We have used both linear and dynamically focused phased arrays for fetal examinations in conjunction with conventional gray scale B-mode scanners. The sophisticated phased-array real-time systems have demonstrated higher resolution and an improved gray scale as compared with the linear arrays. Applications of real-time ultrasound in obstetrics are discussed, and appropriate clinical examples are cited that illustrate the value of the technique for study of both normal and abnormal fetal development. We believe that this technique is the most sensitive method of detecting intrauterine fetal demise. The relative advantages and disadvantages of linear and dynamically focused phased arrays in obstetric evaluation are considered.  相似文献   
98.
江雨珊 《中外医疗》2016,(15):10-12
目的:探究与分析三维超声成像诊断乳腺肿块的临床应用价值。方法方便选取并回顾性分析该院自2013年9月—2015年9月收治的90例乳腺肿块患者的临床资料,该组患者均接受了二维超声、三维超声及弹性成像检查,将上述3种检查结果与术后病理结果进行对照。结果二维超声敏感性为79.03%,特异性为70.83%,准确性为74.63%,三维超声敏感性为89.83%,特异性为78.95%,准确性为84.33%,弹性超声成像敏感性为92.60%,特异性为82.5%,准确性为86.57%,三维超声与弹性超声成像敏感性、特异性及准确性相比均差异无统计学意义(P>0.05)。三维超声与弹性超声成像敏感性、特异性及准确性与二维超声相比均明显增高,差异有统计学意义(P<0.05)。结论三维超声的诊断准确率明显高于二维超声,且与弹性超声成像无明显差异,临床医生可将其应用于乳腺肿块的诊断过程中,为进一步治疗提供合理依据。  相似文献   
99.
目的: 探讨应用超声靶向破坏微泡 (UTMD) 技术介导小鼠肝癌细胞株JNK1基因的表达、细胞迁移和侵袭抑制的作用,阐明其作用机制。方法: 构建并筛选RNA干扰效果最好的短发夹RNA(shRNA)。将小鼠肝癌细胞株Hca-F分为正常Hca-F细胞组、shRNA质粒组、脂质体组、超声微泡结合超声辐照组及脂质体结合超声微泡加超声辐照组。采用倒置荧光显微镜观察各组细胞转染率,荧光定量PCR和Western blotting 法检测JNK1基因mRNA和蛋白表达水平,CCK-8法检测各组细胞的细胞活性,应用Transwell 实验检测各组细胞的体外迁移能力。结果: 脂质体结合超声微泡加超声辐照组细胞转染率高于shRNA质粒组、脂质体组和超声微泡结合超声辐照组(均P<0.05),脂质体组和超声微泡结合超声辐照组比较差异无统计学意义(P>0.05)。脂质体结合超声微泡加超声辐照组JNK1 mRNA和蛋白表达水平低于其他各组(P<0.05);脂质体结合超声微泡加超声辐照组细胞活性和平均穿膜细胞数均低于其他各组(P<0.05)。结论: UTMD技术结合脂质体转染法可以提高小鼠肝癌细胞株JNK1 shRNA的转染效率,增强其对基因表达、细胞活力、迁移和侵袭能力的抑制。  相似文献   
100.
目的:分析多节段胸椎后纵韧带骨化症(ossification of the posterior longitudinal ligament, OPLL)术中超声辅助下环形减压术的手术疗效和术后神经功能改善情况。方法:选择2016年1月至2021年1月北京大学第三医院多节段胸椎OPLL患者的病例资料进行回顾性分析,所有病例均完成后壁切除后行术中超声检查确定环形减压节段,并进行环形减压。纳入研究的30例患者男性14例,女性16例,平均年龄(49.3±11.4)岁。首发症状以下肢麻木无力为主(83.3%),平均症状持续时间为(33.9±42.9)个月(1~168个月)。神经功能通过术前及末次随访时改良日本骨科协会(modified Japanese Orthopedic Association, mJOA)评分(0~11分)评估,神经功能改善率根据Harabayashi法计算。根据神经功能改善率是否大于25%将患者分为较优改善组和较差改善组,收集两组患者的年龄、体重指数(body mass index, BMI)、病程时间、手术时间、出血量、mJOA评分、手术节段、脑脊液漏并进行分析比较。结...  相似文献   
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