Polarization-sensitive OCT as an early predictor of spontaneous pre-term birth.

自发早产每年花费英国NHS超过10亿英镑，是年轻人残疾的主要原因。在正常的38周妊娠期之前出生的婴儿必须在孵化器中人工存活。现代孵化器代表了早产儿医疗保健的巨大进步，这意味着早在妊娠28周出生的婴儿现在有80-90%的机会存活到成年。尽管如此，早产儿在成长过程中患脑瘫、智力发育迟缓、视力和听力缺陷、呼吸困难等残疾的风险增加。因此，世界各地的产科医生和妇科医生都在迫切地尝试开发能够预测特定妇女何时可能有早产风险的工具，因此可以采取预防措施来尝试延迟分娩和/或尝试在婴儿出生之前加速婴儿肺部的发育。目前正在进行大量的研究，以开发这样一种预测工具，特别是在谢菲尔德，我们正在开创性的方法，物理检查宫颈组织本身，以及分析母亲的血液或阴道液样本。然而，尽管做出了这些努力，研究人员仍在继续寻找一种足够可靠的测试方法，以便对医生有用，人类胎儿在子宫内发育，并包含在称为胎盘的保护性充满液体的袋子中。胎盘由子宫颈固定，子宫颈是将子宫与阴道分开的狭窄开口。子宫颈的机械强度将发育中的婴儿保持在母亲体内，直到准备好分娩。正常的分娩需要子宫颈的软化（技术上称为“成熟”），以便婴儿能够挤出。大多数身体组织的力量，包括子宫颈，来自一种叫做胶原蛋白的蛋白质。随着年龄的增长，我们皮肤中的胶原蛋白含量福尔斯下降，因此我们的皮肤变得更松弛，更有弹性。胶原蛋白可以被称为松弛素的激素降解;这种激素是由女性身体在怀孕期间产生的，被认为有助于减少子宫颈内的胶原蛋白含量。如果胶原蛋白降解率过高，自发性早产的风险是否会增加？在怀孕的不同阶段，是否有可能非侵入性地测量子宫颈胶原蛋白含量的“指数”？如果是这样的话，该指数是否能够识别出早产风险较高的女性，以便及时进行治疗以避免早产？我们将通过构建一种新型的新型相机来回答这些问题，该相机可以通过插入阴道并放置在离子宫颈表面几毫米处的小型成像探头（类似于锁孔手术中使用的探头）来测量子宫颈的胶原蛋白含量。该程序将类似于一种名为“阴道镜”的检查（旨在检测宫颈癌），但将重点放在胶原蛋白的丰度上，而不是细胞的健康状况。我们的技术被称为“偏振敏感光学相干断层扫描”，我们已经证明它可以测量子宫颈组织样本的胶原蛋白含量，这些样本是由接受子宫颈切除术的妇女慷慨捐赠的。下一步是在临床上使用这种测量技术，在自然状态下对宫颈进行成像。为此，我们将建立一种新型的成像探头和相关的数据收集系统，然后在志愿者中进行试验测量。我们将了解这项技术在预测早产方面的潜在好处。

Spontaneous pre-term birth costs the UK NHS over £1billion annually and is a major cause of disability in the young. Babies that are born before the normal 38 weeks of gestation must spend the first weeks or months of their lives being kept alive artificially in incubators. Modern incubators represent a huge advance in medical care for premature babies and means that babies born as early as 28 weeks gestation now have an 80-90% chance of surviving to adulthood. Nonetheless, premature babies have an increased risk of growing up with disabilities such as cerebral palsy, retarded mental development, visual and hearing defects, breathing difficulties etc. Obstetricians and gynaecologists around the world are thus urgently trying to develop tools that can predict when a particular woman might be at risk of delivering her baby prematurely, so that preventative measures can be taken to try to delay the delivery and/or to try to speed up the development of the baby's lungs before he or she is born. A great deal of research is being undertaken currently to develop such a predictive tool, especially at Sheffield where we are pioneering methods that physically examine the cervical tissues themselves, as well as analyzing samples of the mother's blood or vaginal fluid. Despite these efforts however, the search is still ongoing to find a test that is sufficiently reliable to be useful to doctors, The human foetus develops in the womb and is contained within the protective, fluid-filled sack called the placenta. The placenta is held in position by the cervix, which is the narrow opening that separates the womb from the vagina. The mechanical strength of the cervix is what holds the developing baby inside the mothers body until it is ready to be delivered. Normal birth requires a softening (technically called "ripening") of the cervix, so that the baby can squeeze its way out. The strength of most body tissues, including the cervix, comes from a protein called collagen. As we age, the collagen content of our skin falls and so our skin becomes looser and more stretchy. Collagen can be degraded by a hormone called relaxin; this hormone is produced by the female body during pregnancy and is believed to contribute to a reduction in collagen content within the cervix. Might the risk of spontaneous preterm birth increase if the rate of collagen degradation is too high? Might it be possible to measure an "index" of collagen content of the cervix non-invasively, at various stages of a pregnancy? If so, might this index be able to identify women with an elevated risk of delivering prematurely sufficiently early that treatments can be applied in time to avoid the premature delivery? We will answer these questions by building a novel new type of camera that can measure the collagen content of the cervix, via a small imaging probe (similar to those used in keyhole surgery) that is inserted into the vagina and placed a few millimeters from the surface of the cervix. The procedure will be similar to an examination called "colposcopy" (which aims to detect cervical cancer) but will focus on the abundance of the collagen protein, not the health of the cells. Our technique is called "polarization sensitive optical coherence tomography" and we have already shown that it can measure the collagen content of cervical tissue samples that have been generously donated by women undergoing hysterectomies. The next stage is to use this measurement technique in the clinic, to image the cervix in its natural state. to this we will build a novel imaging probe and associated data collection system and then make trial measurements in volunteers. We will this learn what is the potential benefits of this technology for predicting pre-term birth.