Estimating Ultrasound Attenuation in Human Pregnant Cervix

描述（由申请人提供）：早产是母亲及其婴儿的严重医疗保健问题。在过去的40年里，尽管采取了干预措施来阻止早产的发生，但早产的发生率并没有降低。早产给社会带来的代价是惊人的。在美国，早产是婴儿死亡的第二大原因，也是黑人婴儿死亡的主要原因。我们推测，早期诊断和治疗策略，需要在妇女目前与早产的收缩。对早产宫颈成熟机制的理解的进展导致了动物和一些人类干预来改变人类宫颈成熟。缺少的是一种客观的非侵入性方法来检测宫颈组织微结构的变化与宫颈成熟一致。这项研究计划的长期目标是开发一种非侵入性超声技术，该技术将检测人类早期宫颈成熟，并导致科学干预以改变早产。宫颈缩短和扩张可以用临床超声系统检测到。然而，一个客观的非侵入性的方法来确定与宫颈成熟相关的组织性质的变化（增加胶原解体和水浓度）并不存在。超声衰减（超声波在组织中传播时的能量损失）的估计已用于评估健康和疾病中组织的结构和功能。已经发现衰减与组织硬度、胶原蛋白含量和组织的水浓度有关。我们希望通过评估两个孕妇样本的宫颈衰减，将我们在动物模型中检测宫颈组织变化的能力转化为人类妊娠中的变化。在第一个样本（n = 25）中，我们将在人类妊娠过程中对宫颈衰减进行6次评估，以确定是否可以检测到差异以及是否可以在纵向研究中招募/保留女性。在第二个样本（n = 20）中，我们将确定衰减的估计值是否可以检测到与医学诱导的宫颈成熟（一个已知的过程，在短时间内发生明显的宫颈组织变化）相关的宫颈变化。在妊娠期必须通过药物引产的情况下，在引产前，使用前列腺素等药物可加速宫颈成熟过程。56前列腺素可在5至12小时内使宫颈明显成熟。本研究的具体目标是确定：目标1。招募和保留孕妇进行纵向超声研究的可行性。目标2.人类妊娠中宫颈衰减的纵向评估是否可以检测到妊娠过程中与宫颈成熟相关的宫颈变化。目标3：超声衰减估计是否可以检测到人类妊娠中药物诱导宫颈成熟前后的差异。 公共卫生相关性：早产的治疗集中在治疗宫缩，而不是早产前宫颈“成熟”或变薄的长期过程。对早产宫颈成熟机制的理解的进展导致了动物和人类干预来改变人类宫颈成熟。目前缺少的是一种非侵入性的方法来检测这种变化。这项研究计划的长期目标是开发一种非侵入性超声技术，该技术将检测人类早期宫颈成熟，并导致科学干预以改变早产。

DESCRIPTION (provided by applicant): Preterm birth is a serious healthcare concern for mothers and their infants. The incidence of preterm birth has not been reduced in the last 40 years in spite of interventions to stop contractions of preterm labor. The cost of prematurity to society is staggering. In the United States, prematurity is the second leading cause of infant mortality and the leading cause of infant mortality for Black infants. We postulate that earlier diagnosis and treatment strategies are needed before women present with the contractions of preterm labor. Advances in the understanding of mechanisms of preterm cervical ripening have led to both animal and some human interventions to modify human cervical ripening. What is missing is an objective noninvasive method to detect changes in cervix tissue microstructure consistent with cervical ripening. The long-term goal of this research program is to develop a noninvasive ultrasound technique that will detect early cervical ripening in humans and lead to scientific interventions to modify preterm birth. Cervical shortening and dilation can be detected with clinical ultrasound systems. However, an objective noninvasive method to determine tissue property changes (increased collagen disorganization and water concentration) associated with cervical ripening does not exist. Estimates of ultrasound attenuation (the loss of energy as an ultrasonic wave propagates through tissue) have been used to evaluate the structure and function of tissue in health and disease. Attenuation has been found to be related to tissue stiffness, collagen content and water concentration of tissues. We want to translate our capabilities to detect cervical tissue changes in the animal model to those changes in human pregnancy by assessing cervical attenuation in two samples of pregnant women. In the first sample (n = 25), we will conduct six assessments of cervical attenuation over the course of human pregnancy to determine whether differences can be detected and whether women can be recruited/retained in a longitudinal study. In the second sample (n = 20), we will determine whether estimates of attenuation can detect changes in the cervix associated with medically induced cervical ripening (a known process where marked cervix tissue changes occur in a short time frame). In conditions where labor must be medically induced in pregnancy, pharmacological agents such as prostaglandins can accelerate the process of cervical ripening before inducing the contractions of labor.56 Prostaglandins have been noted to produce marked cervical ripening in five to twelve hours. The specific aims of this study are to determine: Aim 1. The feasibility of recruitment and retention of pregnant women for a longitudinal ultrasound study. Aim 2. Whether longitudinal assessments of cervical attenuation in human pregnancy can detect changes in the cervix associated with cervical ripening over the course of pregnancy. Aim 3. Whether ultrasound attenuation estimates can detect differences between pre- and post medically induced cervical ripening in term human pregnancy. PUBLIC HEALTH RELEVANCE: Treatment of preterm labor has focused on treating contractions rather than the long process of cervical "ripening" or thinning that precedes preterm labor. Advances in the understanding of mechanisms of preterm cervical ripening have led to both animal and human interventions to modify human cervical ripening. What is missing is a noninvasive method to detect such changes. The long-term goal of this research program is to develop a noninvasive ultrasound technique that will detect early cervical ripening in humans and lead to scientific interventions to modify preterm birth.