Zanini Marco Antonio, de Lima Resende Luiz Antonio, de Souza Faleiros Antonio Tadeu, Gabarra Roberto Colichio
Department of Neurology and Psychiatry, School of Medicine of Botucatu, São Paulo State University, Botucatu, Brazil.
J Trauma. 2008 Mar;64(3):705-13. doi: 10.1097/TA.0b013e3180485cfc.
Traumatic subdural hygroma (TSHy) is an accumulation of cerebrospinal fluid (CSF) in the subdural space after head injury. It appears to be relatively common, but its onset time and natural history are not well defined. Considered a benign epiphenomenon of trauma, the pathogenesis of TSHy is still unclear and many questions remain unanswered. This study adds to the information on TSHy, and proposes a classification based on pathogenesis.
Thirty-four consecutive adult patients with TSHy were analyzed for clinical evolution and serial CT scan, during a period of several months. TSHy diagnosis was based on published CT scan criteria of hypodense subdural collection after trauma, without enhancement and neomembrane, with a minimum distance of 3 mm between the skull and brain. Ventricle size was analyzed by calculating the bicaudate index (BCI). For comparison, the BCI was measured from CT scan at three moments: admission, at time of TSHy diagnosis, and from last CT scan.
There were 34 patients, aged between 16 and 85 years (mean 40), half of them were below 40 years. Road traffic crashes were the main cause of head injury. The mean time for hygroma diagnosis was 9 days. Twenty-one patients (61.8%) underwent conservative treatment for TSHy and 13 (38.2%), surgical treatment. TSHy are early lesions and can be detected in the first 24 hours after trauma, usually as small subdural effusion (SSEff). Based on clinical and CT scan findings, we divided the 34 patients into 3 groups, (Ia and Ib) without evident mass effect and (II) with evident mass effect. Group Ia includes patients without ventricle dilation; Ib, patients with associated ventricle dilations.
SSEff detected in the first 24 hours posttrauma in our series evolved into TSHy suggesting that this is an early lesion; all THSy were divided in three groups according to the pathophysiologic mechanism. These three groups probably represent a continuum of CSF absorption impairment. Group Ia represents what most authors consider a simple hygroma, with no impairment on CSF absorption. Group Ib represent the external hydrocephalus form with various degrees of CSF imbalance, and group II were the cases presenting marked mass effect.
创伤性硬膜下积液（TSHy）是头部受伤后硬膜下腔脑脊液（CSF）的积聚。它似乎相对常见，但其发病时间和自然病程尚不明确。TSHy被认为是创伤的一种良性附带现象，其发病机制仍不清楚，许多问题仍未得到解答。本研究补充了有关TSHy的信息，并提出了一种基于发病机制的分类方法。
对34例连续的成年TSHy患者进行了为期数月的临床病程和系列CT扫描分析。TSHy的诊断基于已发表的创伤后硬膜下低密度积液的CT扫描标准，无强化和新膜形成，颅骨与脑之间的最小距离为3毫米。通过计算双尾状核指数（BCI）分析脑室大小。为作比较，在三个时间点从CT扫描测量BCI：入院时、TSHy诊断时和最后一次CT扫描时。
有34例患者，年龄在16至85岁之间（平均40岁），其中一半年龄在40岁以下。道路交通事故是头部受伤的主要原因。积液诊断的平均时间为9天。21例患者（61.8%）接受了TSHy的保守治疗，13例（38.2%）接受了手术治疗。TSHy是早期病变，可在创伤后24小时内检测到，通常为小的硬膜下积液（SSEff）。根据临床和CT扫描结果将34例患者分为3组，（Ia和Ib）无明显占位效应组和（II）有明显占位效应组。Ia组包括无脑室扩张的患者；Ib组为伴有脑室扩张的患者。
在我们的系列研究中，创伤后24小时内检测到的SSEff演变为TSHy，提示这是一种早期病变；所有TSHy根据病理生理机制分为三组。这三组可能代表脑脊液吸收障碍的一个连续过程。Ia组代表大多数作者认为的单纯积液，脑脊液吸收无损害。Ib组代表具有不同程度脑脊液失衡的外部脑积水形式，II组为出现明显占位效应的病例。
