BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that t...BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that timely interventions can be implemented to safeguard the health and safety of the fetus.AIM To identify the relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine distress.METHODS Clinical data of pregnant women admitted between January 2021 and January 2023 were collected and divided into the observation and control groups(n=50 each),according to the presence or absence of intrauterine distress.The ultrasound hemodynamic parameters of the uterine artery(UtA),fetal middle cerebral artery(MCA),and umbilical artery(UmA)were compared with neonatal outcomes and occurrence of intrauterine distress in the two groups.RESULTS Comparison of ultrasonic hemodynamic parameters,resistance index(RI),pulsatility index(PI),and systolic maximal blood flow velocity of UmA compared to diastolic blood flow velocity(S/D),revealed higher values of fetal MCA,PI,and S/D of UmA in pregnant women with UtA compared to controls(P<0.05),while there was no difference between the two groups in terms of RI(P<0.05)The incidence of a neonatal Apgar score of 8-10 points was lower in the observation group(66.7%)than in the control group(90.0%),and neonatal weight(2675.5±27.6 g)was lower than in the control group(3117.5±31.2 g).Further,cesarean section rate was higher in the observation group(70.0%)than in the control group(11.7%),and preterm labor rate was higher in the observation group(40.0%)than in the control group(10.0%).The incidence of fetal distress,neonatal growth restriction and neonatal asphyxia were also higher in the observation group(all P<0.05).CONCLUSION Fetal MCA,UmA,and maternal UtA hemodynamic abnormalities all develop in pregnant women with intrauterine distress during late pregnancy,which suggests that clinical attention should be paid to them,and monitoring should be strengthened to provide guidance for clinical intervention.展开更多
Coded excitation technology (CET) can effectively enhance the penetration and resolution of ultrasonic testing. To analyze the influence of rock properties on pulse compression performance (PCP) of coded excitatio...Coded excitation technology (CET) can effectively enhance the penetration and resolution of ultrasonic testing. To analyze the influence of rock properties on pulse compression performance (PCP) of coded excitation signals (CES), a numerical simulation, and an ultrasonic experiment on different rock samples are performed; and the detection ability of several CESs are also investigated and compared. The results of experiments showed that the loss of the signal-to-noise ratio (SNR) of Barker coded signal with tapered linear frequency modulated carrier (BTLFM) is always less than Barker coded signal with sine carrier (BS), while the resolution loss of BTLFM is lower than tapered linear frequency modulated signal (TLFM). In sum, the results not only verifiy the effectiveness of CET, but also provide a basis for the parameter settings of coded signals used in rock ultrasonic testing.展开更多
Ultrasound is widely used in biomedical engineering and has applications in conventional diagnosis and drug delivery.Recent advances in ultrasound-induced drug delivery have been summarized previously in several revie...Ultrasound is widely used in biomedical engineering and has applications in conventional diagnosis and drug delivery.Recent advances in ultrasound-induced drug delivery have been summarized previously in several reviews that have primarily focused on the fabrication of drug delivery carriers.This review discusses the mechanisms underlying ultrasound-induced drug delivery and factors affecting delivery efficiency,including the characteristics of drug delivery carriers and ultrasound parameters.Firstly,biophysical effects induced by ultrasound,namely thermal effects,cavitation effects,and acoustic radiation forces,are illustrated.Secondly,the use of these biophysical effects to enhance drug delivery by affecting drug carriers and corresponding tissues is clarified in detail.Thirdly,recent advances in ultrasound-triggered drug delivery are detailed.Safety issues and optimization strategies to improve therapeutic outcomes and reduce side effects are summarized.Finally,current progress and future directions are discussed.展开更多
BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcome...BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcomes such as miscarriage,preterm birth,and other complications.Early detection and accurate assessment of SCH are crucial for appropriate management and improved pregnancy outcomes.AIM To evaluate the diagnostic efficacy of virtual organ computer-assisted analysis(VOCAL)in measuring the volume ratio of SCH to gestational sac(GS)combined with serum progesterone on early pregnancy outcomes in patients with SCH.METHODS A total of 153 patients with SCH in their first-trimester pregnancies between 6 and 11 wk were enrolled.All patients were followed up until a gestational age of 20 wk.The parameters of transvaginal two-dimensional ultrasound,including the circumference of SCH(Cs),surface area of SCH(Ss),circumference of GS(Cg),and surface area of GS(Sg),and the parameters of VOCAL with transvaginal three-dimensional ultrasound,including the three-dimensional volume of SCH(3DVs)and GS(3DVg),were recorded.The size of the SCH and its ratio to the GS size(Cs/Cg,Ss/Sg,3DVs/3DVg)were recorded and compared.RESULTS Compared with those in the normal pregnancy group,the adverse pregnancy group had higher Cs/Cg,Ss/Sg,and 3DVs/3DVg ratios(P<0.05).When 3DVs/3DVg was 0.220,the highest predictive performance predicted adverse pregnancy outcomes,resulting in an AUC of 0.767,and the sensitivity,specificity were 70.2%,75%respectively.VOCAL measuring 3DVs/3DVg combined with serum progesterone gave a diagnostic AUC of 0.824 for early pregnancy outcome in SCH patients,with a high sensitivity of 82.1%and a specificity of 72.1%,which showed a significant difference between AUC.CONCLUSION VOCAL-measured 3DVs/3DVg effectively quantifies the severity of SCH,while combined serum progesterone better predicts adverse pregnancy outcomes.展开更多
文摘BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that timely interventions can be implemented to safeguard the health and safety of the fetus.AIM To identify the relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine distress.METHODS Clinical data of pregnant women admitted between January 2021 and January 2023 were collected and divided into the observation and control groups(n=50 each),according to the presence or absence of intrauterine distress.The ultrasound hemodynamic parameters of the uterine artery(UtA),fetal middle cerebral artery(MCA),and umbilical artery(UmA)were compared with neonatal outcomes and occurrence of intrauterine distress in the two groups.RESULTS Comparison of ultrasonic hemodynamic parameters,resistance index(RI),pulsatility index(PI),and systolic maximal blood flow velocity of UmA compared to diastolic blood flow velocity(S/D),revealed higher values of fetal MCA,PI,and S/D of UmA in pregnant women with UtA compared to controls(P<0.05),while there was no difference between the two groups in terms of RI(P<0.05)The incidence of a neonatal Apgar score of 8-10 points was lower in the observation group(66.7%)than in the control group(90.0%),and neonatal weight(2675.5±27.6 g)was lower than in the control group(3117.5±31.2 g).Further,cesarean section rate was higher in the observation group(70.0%)than in the control group(11.7%),and preterm labor rate was higher in the observation group(40.0%)than in the control group(10.0%).The incidence of fetal distress,neonatal growth restriction and neonatal asphyxia were also higher in the observation group(all P<0.05).CONCLUSION Fetal MCA,UmA,and maternal UtA hemodynamic abnormalities all develop in pregnant women with intrauterine distress during late pregnancy,which suggests that clinical attention should be paid to them,and monitoring should be strengthened to provide guidance for clinical intervention.
基金supported by the National Natural Science Foundation of China(41104117)
文摘Coded excitation technology (CET) can effectively enhance the penetration and resolution of ultrasonic testing. To analyze the influence of rock properties on pulse compression performance (PCP) of coded excitation signals (CES), a numerical simulation, and an ultrasonic experiment on different rock samples are performed; and the detection ability of several CESs are also investigated and compared. The results of experiments showed that the loss of the signal-to-noise ratio (SNR) of Barker coded signal with tapered linear frequency modulated carrier (BTLFM) is always less than Barker coded signal with sine carrier (BS), while the resolution loss of BTLFM is lower than tapered linear frequency modulated signal (TLFM). In sum, the results not only verifiy the effectiveness of CET, but also provide a basis for the parameter settings of coded signals used in rock ultrasonic testing.
基金supported by the National Natural Science Foundation of China(31971169,81822022,81771846,81571810)the Beijing Natural Science Foundation(7182180)+2 种基金National Key Research and Development Program of China(2018YFC0116003,2016YFA0201400)Beijing Talents Foundation(2018000021223ZK48)Peking University Third Hospital(BYSYZD2019018,jyzc2018-02,BYSY2015023)。
文摘Ultrasound is widely used in biomedical engineering and has applications in conventional diagnosis and drug delivery.Recent advances in ultrasound-induced drug delivery have been summarized previously in several reviews that have primarily focused on the fabrication of drug delivery carriers.This review discusses the mechanisms underlying ultrasound-induced drug delivery and factors affecting delivery efficiency,including the characteristics of drug delivery carriers and ultrasound parameters.Firstly,biophysical effects induced by ultrasound,namely thermal effects,cavitation effects,and acoustic radiation forces,are illustrated.Secondly,the use of these biophysical effects to enhance drug delivery by affecting drug carriers and corresponding tissues is clarified in detail.Thirdly,recent advances in ultrasound-triggered drug delivery are detailed.Safety issues and optimization strategies to improve therapeutic outcomes and reduce side effects are summarized.Finally,current progress and future directions are discussed.
文摘BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcomes such as miscarriage,preterm birth,and other complications.Early detection and accurate assessment of SCH are crucial for appropriate management and improved pregnancy outcomes.AIM To evaluate the diagnostic efficacy of virtual organ computer-assisted analysis(VOCAL)in measuring the volume ratio of SCH to gestational sac(GS)combined with serum progesterone on early pregnancy outcomes in patients with SCH.METHODS A total of 153 patients with SCH in their first-trimester pregnancies between 6 and 11 wk were enrolled.All patients were followed up until a gestational age of 20 wk.The parameters of transvaginal two-dimensional ultrasound,including the circumference of SCH(Cs),surface area of SCH(Ss),circumference of GS(Cg),and surface area of GS(Sg),and the parameters of VOCAL with transvaginal three-dimensional ultrasound,including the three-dimensional volume of SCH(3DVs)and GS(3DVg),were recorded.The size of the SCH and its ratio to the GS size(Cs/Cg,Ss/Sg,3DVs/3DVg)were recorded and compared.RESULTS Compared with those in the normal pregnancy group,the adverse pregnancy group had higher Cs/Cg,Ss/Sg,and 3DVs/3DVg ratios(P<0.05).When 3DVs/3DVg was 0.220,the highest predictive performance predicted adverse pregnancy outcomes,resulting in an AUC of 0.767,and the sensitivity,specificity were 70.2%,75%respectively.VOCAL measuring 3DVs/3DVg combined with serum progesterone gave a diagnostic AUC of 0.824 for early pregnancy outcome in SCH patients,with a high sensitivity of 82.1%and a specificity of 72.1%,which showed a significant difference between AUC.CONCLUSION VOCAL-measured 3DVs/3DVg effectively quantifies the severity of SCH,while combined serum progesterone better predicts adverse pregnancy outcomes.