In trisomy 9 mosaicism, plexus hypertrophy has been described as a phenotypical feature and cause of hydrocephalus. We report on a 15-month-old child with hydrocephalus and trisomy 9 mosaicism primarily diagnosed in amniocentesis. After implantation of a ventriculoperitoneal shunt and subsequent revision, he presented with an exhaustion of peritoneal absorption leading to massive ascites. The implantation of a peritoneal drainage offered the unique opportunity to monitor cerebrospinal fluid (CSF) production indirectly via abdominal CSF drainage. In an individual trial, we performed endoscopic choroid plexus cauterization to reduce cerebrospinal fluid production, which failed to reduce excessive CSF production. In a second procedure, a ventriculoatrial shunt was implanted and succeeded to treat persistent hydrocephalus.

中文翻译：

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脉络丛凝血在三体性9镶嵌相关脑积水中的一例报道。

在三体性9镶嵌症中，神经丛肥大已被描述为一种表型特征和脑积水的病因。我们报告了一个主要在羊膜穿刺术中诊断为脑积水和三体9马赛克的15个月大儿童。植入腹膜－腹膜分流术并随后翻修后，他表现出腹膜吸收力竭，导致大量腹水。腹膜引流的植入提供了独特的机会，可通过腹部CSF引流间接监测脑脊液（CSF）的产生。在一项单独的试验中，我们进行了内窥镜脉络膜烧灼术，以减少脑脊液的产生，但未能减少过多的CSF产生。在第二个步骤中，植入了脑室分流术并成功治疗了持续性脑积水。