杜雷特（Duret）出血

Duret Hemorrhage

杜雷特出血

来源：《Brain Imaging with MRI and CT》case 64

本章作者：MAURICIO CASTILLO

大师风采（006）：高产神经放射学家Mauricio Castillo

薛琪译站（004）：磁敏感加权成像相位图的临床应用及其局限性

精彩PPT（027）：磁敏感加权像的临床应用及限度

这两个PPT也有MAURICIO CASTILLO的参与！

翻译：张太娟（青岛市中医医院影像科主治医师）

Figure 1. Non-enhanced axial CT image (A) shows a round hemorrhage (arrow) in the upper pons and a second one in its left dorsolateral aspect (white arrowhead). The brainstem is hypodense due to edema. There is subarachnoid hemorrhage and a right subdural hematoma (black arrowheads).

A more cephalad CT (B) shows transtentorial herniation of the right uncus (arrows) with compression of the brainstem (*) and dilation of the left lateral ventricle (arrowheads) indicating entrapment.

图1.CT平扫（A）显示脑桥上部一类圆形出血灶（箭示），它的背外侧可见另一个病灶（白箭头示）。脑干因为水肿呈低密度改变。另外可见蛛网膜下腔出血和右侧硬膜下血肿（黑箭头示）。

B图是A图的上一层面，显示小脑幕切迹疝，海马钩回（箭示）挤入小脑幕切迹压迫脑干（星号示），并伴有左侧侧脑室颞角扩张，提示室间孔阻塞。

Figure 2. CT image shows a central upperpontine hemorrhage (arrow). There is alsodiffuse subarachnoid hemorrhage(arrowheads).

图2.CT平扫图像显示脑桥上部中心灶状出血（箭示），并可见弥漫性蛛网膜下腔出血（箭头示）。

Figure 3. CT image in another patient demonstrates a rounded central hemorrhage (arrow) within the upper pons. Also note a left extra-axial hematoma (white arrowheads) and a small amount of pneumocephalus(black arrowhead) indicating skull fracture.

图3.另一个病人CT平扫图像显示脑桥上部中心圆形出血灶（箭示）。白箭头示左侧脑外血肿，并可见少量的颅内积气改变

（黑箭头示），提示颅骨骨折。

Figure 4. Predominantly linear hemorrhage (arrows) within the mid to lower pons is shown on CT (A). The brainstem is hypodense and swollen from edema. Subarachnoid blood (white arrowhead) and left posterior fossa extra-axial hematoma (black arrowheads) are present. Coronal T2WI (B) reveals right uncal herniation (arrowhead) with contralateral and inferior displacement of the pons.

Also note a right epidural hematoma (*), leftward midline shift and enlarged trapped left lateral ventricle (white arrowheads).

图4.CT图像（A）显示脑桥中下部主要表现为线状的出血灶（箭示）。脑干因为水肿呈低密度并肿胀。白箭头示蛛网膜下腔出血，黑箭头示左侧后颅窝脑外血肿。冠状位T2WI（B）显示右侧钩回疝，脑桥向对侧及下方移位，并可见右侧硬膜外血肿（星号示）、中线左移、左侧侧脑室阻塞扩张。

Specific Imaging Findings

The imaging method of choice is CT, as these patients tend to be in very poor clinical condition. CT shows low-density edema in the brainstem and generally uncal transtentorial herniation with obliteration of the cisterns. Downward herniation is more difficult to identify,but inferior displacement of the cerebellar tonsils without a clear posterior fossa space-occupying lesion suggests it. Within the hypodense brainstem the acute hemorrhages are seen as focal areas of high density. They tend to be of a linear configuration, extending in from ventral to dorsal,but may have any shape.Hemorrhages are generally found in the pons, but may be located in the medulla and/or mid-brain. Duret hemorrhage may be accompanied with other lesions in the brainstem such as shear injuries. MRI with its inherent increased sensitivity to subacute blood products may help to identify them later.

特征性影像学表现

首选的影像学检查是CT，因为这些病人临床症状重、条件差。CT显示脑干水肿呈低密度，一般会有钩回小脑幕切迹疝并脑池受压闭塞改变。脑组织向下疝有时候很难确定，但是通过观察小脑扁桃体向下移位并且后颅窝未发现占位性病变，提示下疝的存在。在低密度的脑干中可见局灶性高密度出血灶。出血灶倾向于表现为线状形态，从脑干腹侧到背侧走行，但是可见各种形态改变。出血灶一般位于脑桥，但是也可以见于延髓和/或中脑。杜雷特出血可以伴有其他脑干病变如剪切伤。MRI因为它对亚急性出血产物先天的敏感性，稍后也能帮助我们明确诊断。

Pertinent Clinical Information

Duret hemorrhages are considered secondary brain injuries and in most patients there is a significant supratentorial abnormality leading to transtentorial herniations. Because intracranial trauma is strongly associated with these hemorrhages, they tend to be found in younger patients. Most patients are obtunded or comatose and show significant brainstem-associated findings (decerebration) which depend also upon the severity of the herniation and extent of the hemorrhages.

临床表现

杜雷特出血被认为是一种继发的脑损伤，在大部分病人中都有明显的幕上异常，从而导致小脑幕切迹疝。因为这些出血与颅脑损伤明显的相关，也就多见于年轻病人。大部分病人出现迟钝或昏迷，出现明显的脑干相关表现（去大脑改变），这些也取决于脑疝的严重性和出血的范围。

Differential Diagnosis

1. Shearing Injuries (DAI) (114)

· generally affect the dorsolateral aspect of the brainstem

· accompanied by supratentorial axonal injuries, generally not hemorrhagic and bright on DWI

2. Hypertensive Hematoma (177)

· generally larger

· possible history of uncontrolled hypertension

· no supratentorial acute abnormalities,no transtentorial herniations

· typically spontaneous, non-traumatic

鉴别诊断

1. 剪切伤（DAI）

· 一般累及脑干背外侧面

· 伴有幕上轴索损伤，一般不出血，DWI为高信号。

2. 高血压血肿

· 一般更大

· 有难控制高血压病史

· 无幕上急性病变，无小脑幕切迹疝

· 典型的为自发性而非外伤造成。

Background

Increased supratentorial pressure leading to transtentorial herniation is the main cause of Duret hemorrhages. These findings were first described in 1955. Regardless of the cause of the herniation, the results are the same. The term Kernohan notch refers to an indentation in the lateral aspect of the upper brainstem contralateral to the herniation, which accompanies Duret hemorrhages. Not only is side-to-side herniation responsible, many think that cranio-caudad herniation must also be present for these bleeds to occur. As the brainstem is displaced there is traction on the perforating arteries, stretching them and tearing them, resulting in bleeding inside the brainstem. It is also possible that veins are stretched, occluded and that the hemorrhages are the result of venous infarctions. Duret hemorrhages may occur after craniotomy and their etiology in this setting is uncertain. Duret hemorrhages generally portray a poor prognosis although patients with a good recovery have been reported.

背景知识

幕上压力增高引起的小脑幕切迹疝是杜雷特出血的主要原因。这些表现在1955年首次报道。不考虑造成疝的原因，脑干病变都是一样的。“Kernohan切迹”是指脑疝对侧脑干上部外侧面受小脑幕压迫形成的凹陷，伴有杜雷特出血。不仅左右方向的脑疝可以造成这些表现，头尾方向的脑疝也可以造成这种出血。因为脑干移位，其内穿支动脉受牵拉破裂，导致脑干内出血；也可能是静脉受牵拉阻塞，继而静脉性梗死出血。杜雷特出血也见于开颅术后，病因尚不明确。尽管有报道称一些病人恢复很好，但是杜雷特出血一般预后不良。

参考文献

1. Parizel PM, Makkat S, Jorens PG, et al. Brainstem hemorrhage in descending transtentorial herniation (Duret hemorrhage). Intensive Care Med 2002;28:85–8.

2. Stiver SI, Gean AD, Manley GT. Survival with good outcome after cerebral herniation and Duret hemorrhage caused by traumatic brain injury. J Neurosurg 2009;110:1242–6.

3. Kamijo Y, Soma K, Kishita R, Hamanaka S. Duret hemorrhage is not always suggestive of poor prognosis: a case of severe hyponatremia. Am J Emerg Med 2005;23:908–10.

4. Duret RL. A rare and little known hemorrhagic syndrome. [In French.] Brux Med 1955;16:797–800.

5. Chew KL, Baber Y, Iles L, O’Donnell C. Duret hemorrhage:

demonstration of ruptured paramedian pontine branches of the basilar artery on minimally invasive, whole body postmortem CT angiography.Forensic Sci Med Pathol 2012 Apr 7. [Epub ahead of print]

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