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An intraventricular hemorrhage (or haemorrhage in British English; both abbreviated as IVH) is a bleeding into the brain's ventricular system, where the cerebrospinal fluid is produced and circulates through towards the subarachnoid space. It can result from physical trauma or from hemorrhaging in stroke. ==In infants== This type of hemorrhage is particularly common in infants, especially premature infants or those of very low birth weight.〔Annibale DJ and Hill J. 2006. (Periventricular Hemorrhage-Intraventricular Hemorrhage ). Emedicine.com. Retrieved on June 19, 2007.〕 The cause of IVH in premature infants, unlike that in older infants, children or adults, is rarely due to trauma. Instead it is thought to result from changes in perfusion of the delicate cellular structures that are present in the growing brain, augmented by the immaturity of the cerebral circulatory system, which is especially vulnerable to hypoxic ischemic encephalopathy. The lack of blood flow results in cell death and subsequent breakdown of the blood vessel walls, leading to bleeding. While this bleeding can result in further injury, it is itself a marker for injury that has already occurred. Most intraventricular hemorrhages occur in the first 72 hours after birth.〔 The risk is increased with use of extracorporeal membrane oxygenation in preterm infants. The amount of bleeding varies. IVH is often described in four grades: * Grade I - bleeding occurs just in the germinal matrix * Grade II - bleeding also occurs inside the ventricles, but they are not enlarged * Grade III - ventricles are enlarged by the accumulated blood * Grade IV - bleeding extends into the brain tissue around the ventricles Grades I and II are most common, and often there are no further complications. Grades III and IV are the most serious and may result in long-term brain injury to the infant. After a grade III or IV IVH, blood clots may form which can block the flow of cerebrospinal fluid, leading to increased fluid in the brain (hydrocephalus). There have been various therapies employed into preventing the high rates of morbidity and mortality, including diuretic therapy, repeated lumbar puncture, streptokinase therapy and most recently combination a novel intervention called DRIFT (drainage, irrigation and fibrinolytic therapy). In 2002, a Dutch retrospective study analysed cases where neonatologists had intervened and drained CSF by lumbar or ventricular punctures if ventricular width (as shown on ultrasound) exceeded the 97th centile as opposed to the 97th centile plus 4 mm. Professors Whitelaw's original cochrane 〔 review published in 2001 as well as evidence from previous randomised control trials indicated that interventions should be based on clinical signs and symptoms of ventricular dilatation. An international trial has instead looked an early (97th centile) versus late (97th centile plus 4 mm) for intervening and draining CSF.〔http://www.bris.ac.uk/clinicalsciencenorth/neonatal/ri/phitt.html〕 DRIFT has been tested in an international randomised clinical trial; although it did not significantly lower the need for shunt surgery, severe cognitive disability at two years Bayley (MDI <55) was significantly reduced. Repeated lumbar punctures are used widely to reduce the effects in increased intracranial pressure and an alternative to ventriculo-shunt (VP) surgery that cannot be performed in case of intraventricular haemorrhage. The relative risk of repeated lumbar puncture is close to 1.0, therefore it is not statistically therapeutic when compared to conservative management and does raise the risk of subsequent CSF infection.〔 Another DRIFT trial is planned involving a large number of infants to validate previous data and expand on the viability of performing the invasive procedure nationwide. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「intraventricular hemorrhage」の詳細全文を読む スポンサード リンク
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