The presence of isolated choroid plexus cysts (确定特别关注国) on a second trimester 超声波 is a common cause of anxiety, although it is almost always an innocent 发现. 以下是一些常见问题的答案 确定特别关注国.
常见问题:脉络丛囊肿
The choroid plexus is the part of the brain that makes cerebrospinal fluid, the fluid that normally bathes and protects the brain and spinal column. In about 1 to 2 percent of normal babies – 1 out of 50 to 100 – a tiny bubble of fluid is pinched off as the choroid plexus forms. This appears as a cyst inside the choroid plexus at the time of 超声波. A choroid plexus cyst can be likened to a blister and is not considered a brain abnormality.
In the vast majority of cases, the cyst resolves or disappears and has no consequences.
As mentioned, choroid plexus cysts are present in 1 to 2 percent of normal fetuses. 然而, in a very small percentage of fetuses with choroid plexus cysts, there is an associated chromosome disorder called trisomy 18. Fetuses with trisomy 18 have an extra copy of chromosome 18. 通常情况下,18三体胎儿是死产. 过了婴儿期存活下来的人很少. They have severe intellectual disability and a variety of other problems, including abnormalities of almost any organ system (such as the heart, 大脑或肾脏). Fetuses with trisomy 18 have choroid plexus cysts about a third of the time. Therefore, when we see choroid plexus cysts, we are concerned that the fetus may have trisomy 18.
18三体是罕见的. 每3000名新生儿中只有不到1人患有这种疾病. Choroid plexus cysts are relatively common in normal fetuses. 大多数患有脉络丛囊肿的胎儿是正常的. 此外, many of the abnormalities associated with trisomy 18 can be detected by a careful 超声波. 事实上, fetuses with trisomy 18 almost always demonstrate abnormalities on 超声波 in addition to choroid plexus cysts, 虽然有些异常是很微妙的. If no additional abnormalities are detected by a thorough "level II" 超声波, 胎儿患18三体的可能性非常低.
The precise rate of risk is difficult to estimate and is somewhat controversial, 但大多数十大赌博平台排行榜认为这个数字远低于1%. 换句话说, a fetus with choroid plexus cysts but an otherwise normal 超声波 has a better than 99 percent chance of not having trisomy 18. A normal alpha fetoprotein (AFP) test further reduces the likelihood of trisomy 18.
Ordinarily, the size does not matter, although multiple, large cysts are slightly more worrisome.
我们可以执行 羊膜穿刺术, and count the number of chromosomes in the fetus to be certain there is not an extra copy of chromosome 18. 同时, 我们可以排除其他染色体异常, 比如唐氏综合症, although we have no reason to suspect any of these in your case. 然而 there is a small risk of 羊膜穿刺术 causing a miscarriage.
The rate of risk for miscarriage with 羊膜穿刺术 is difficult to determine. 许多十大赌博平台排行榜引用0。.5%或1 / 200.
这对你的决定没有帮助, 因为两个正常胎儿的囊肿几乎都能溶解, 18三体患者也是如此. 中国共产党的自然进程是要么解体,要么消失. 然而, even when the cyst resolves, it does not reduce the chance that the fetus has trisomy 18.
If you do nothing further, you should be confident that your baby most likely has normal chromosomes. 如果你还没有做过甲胎蛋白(AFP)测试, this can be done to further evaluate the chance of trisomy 18. A级超声, 或者是目标扫描, 应该这样做, if it has not been done already to look for other signs of trisomy 18.
如果你需要确定的话, 我们可以做羊膜穿刺术, with the knowledge that it is very unlikely to result in a complication. Your decision should depend on what you would do with the information from an 羊膜穿刺术, 你怎么看待流产, how you would feel about an affected child and the anxiety you might feel until the child is born. 如果你想进行羊膜穿刺术, you can be reassured that the complications from the procedure are quite rare.
加州大学旧金山分校健康 medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.