Ultrasound and necropsy study of periventricular haemorrhage in preterm infants.

The diagnostic accuracy of cerebral ultrasound for periventricular haemorrhage was determined by comparing this with necropsy findings in 30 preterm neonates of 30 weeks'' gestation or less and birthweight under 1500 g. Ultrasound gave an accurate diagnosis of 85% in infants with germinal layer haemorrhage, 92% in intraventricular haemorrhage, and 97% in intracerebral haemorrhage. False positive errors were caused by vascular congestion; false negative errors occurred when the maximum dimension of haemorrhage was less than 3 mm. Cerebral ultrasound gave a diagnostic accuracy of 63% for periventricular leucomalacia. False negative errors occurred when periventricular leucomalacia was microscopic or when it was out of range of the scanner. The maximum width of the germinal layer was measured in 77 neonates of gestational age 23 to 36 weeks who died and had no periventricular haemorrhage at necropsy. The progressive involution of the germinal layer with increasing gestational age paralleled the steady decrease in incidence of periventricular haemorrhage diagnosed over the same gestational age range. Neonates of the youngest gestational age who had the most extensive germinal layers also had the highest risk for periventricular haemorrhage.     

Serum creatine kinase BB as predictor of periventricular haemorrhage in preterm infants

Serum creatine kinase BB (CK-BB) determinations were performed daily in 49 newborn infants of less than 34 weeks gestation to evaluate its usefulness in predicting the occurrence of periventricular-intraventricular haemorrhage (PIVH). Using ultrasound PIVH was detected in 20 infants (41%); five grade I, seven grade II, two grade III, six grade IV (grading according to Papile et al.). Infants who developed severe PIVH (grade IV) during the study period had significantly higher serum CK-BB activities immediately after birth when compared with infants who developed less severe haemorrhages (grades I, II and III) or no PIVH. We postulate that these high serum enzyme activities are caused by perinatal brain cell damage which is an important antecedent of severe PIVH. Therefore, serum CK-BB activities at birth can be used as predictor of severe PIVH.     

Serum creatine kinase BB as predictor of periventricular haemorrhage in preterm infants

Serum creatine kinase BB (CK-BB) determinations were performed daily in 49 newborn infants of less than 34 weeks gestation to evaluate its usefulness in predicting the occurrence of periventricular-intraventricular haemorrhage (PIVH). Using ultrasound PIVH was detected in 20 infants (41%); five grade I, seven grade II, two grade III, six grade IV (grading according to Papile et al.). Infants who developed severe PIVH (grade IV) during the study period had significantly higher serum CK-BB activities immediately after birth when compared with infants who developed less severe haemorrhages (grades I, II and II) or no PIVH. We postulate that these high serum enzyme activities are caused by perinatal brain cell damage which is an important antecedent of severe PIVH. Therefore, serum CK-BB activities at birth can be used as predictor of severe PIVH.     

A study of periventricular haemorrhage, post-haemorrhagic ventricular dilatation and periventricular leucomalacia in Chinese preterm infants

Serial cranial ultrasound scans were performed in 178 preterm Chinese infants (gestation less than 35 weeks, birthweight less than 2000 g) to study the incidence, age of onset and associating risk factors of periventricular haemorrhage (PVH), and also the occurrence of post-haemorrhagic ventricular dilatation and periventricular leucomalacia (PVL). Sixty-four infants developed haemorrhage, giving an incidence of 36%. Among infants of birthweight less than 1500 and less than 1000 g the respective incidence was 52 and 69%. Seventy-two per cent (46 of 64) of haemorrhages were initially detected within the first 3 days of life, but delayed haemorrhage occurring after 1 week of age occurred in nine infants. In eight of these infants PVH had been shortly preceded by a major clinical disaster. Eleven perinatal factors were found to be significantly associated with PVH but only systemic hypotension showed a significant independent association. Post-haemorrhagic ventricular dilatation developed in 17 (46%) of the 37 infants who survived for more than 1 month after PVH. This was transient in 41%, persistent but stable in 29% and progressive in 29%. PVL was detected in eight infants who survived the initial period following PVH.     

Timing and antecedents of periventricular haemorrhage and of cerebral atrophy in very preterm infants

The brains of 95 consecutively admitted infants born at less than 33 weeks gestation were scanned with ultrasound. Thirty-six (38%) had periventricular haemorrhage (PVH). Eight (8%) had cerebral atrophy (together with PVH in 5).Twelve (40%) of the 30 infants in whom satisfactory timing of PVH was possible bled on the first day of life, but the median age when PVH was first detected was during the second day. The median age when PVH reached its maximum extent was the fourth day. The most significant antecedents of PVH were very short gestation and the presence of severe respiratory illness, particularly hyaline membrane disease, necessitating mechanical ventilation. Analysis of variance showed that pneumothorax arising during ventilation was the single most significant antecedent of PVH. Other significant antecedents, notably prolonged coagulation times, were found almost exclusively in infants with severe respiratory illness.Cerebral atrophy appeared usually to be attributable either to severe asphyxia during delivery or later, or to the formation of cysts at the site of previous haemorrhage into brain tissue.     

Blood pressure,heart rate,and skin temperature in preterm infants: associations with periventricular haemorrhage.

The mean arterial blood pressure (MABP), heart rate, and skin temperature were monitored every 15 minutes in the first 10 days after birth in 34 preterm infants, gestational age 24 to 33 weeks. Ultrasound brain scans carried out daily showed that a periventricular haemorrhage (PVH) occurred in a subgroup of infants (n = 15) of lower birthweight and gestational age. In infants without PVH the daily median of MABP increased with birthweight and postnatal age; that of heart rate was not affected by postnatal age, body weight, or gestational age; and that of skin temperature showed a slight fall with postnatal age. In infants with PVH, on or before the day of PVH, daily medians of MABP and skin temperature were not significantly different from those of infants without PVH, but the daily median of heart rate tended to be slightly higher. The percentage of positive correlations between the 96 15 minute values per day for heart rate and MABP increased with postnatal age and with birthweight, but did not differ in infants who developed a PVH. The coefficient of variation (CV) of the 96 15 minute values for MABP tended to be higher in infants on the day of PVH, and a similar trend was apparent on the day before. The processes of development of blood pressure, heart rate, and skin temperature are similar in infants with or without PVH but at lower gestational ages altered blood pressure control may cause brain haemorrhage.     

Factors associated with periventricular haemorrhage in very low birthweight infants.

Periventricular haemorrhage was diagnosed in vivo in 20 of 29 consecutively admitted infants of birthweight below 1500 g using an ultrasound scanner. Ten (51%) infants with haemorrhages survived. Mortality was related to the extent of the bleeding. Statistically significant associations with respiratory distress, ventilator therapy, metabolic acidosis, and hypercapnia were observed, lending support to their role in the pathogenesis of periventricular haemorrhage.     

早产儿脑室周围白质软化的多因素分析

目的　探讨早产儿脑室周围白质软化 (PVL)的高危因素。方法　对合并PVL与未合并PVL的早产儿(各 2 6例 )进行病例对照研究 ,对 18种危险因素进行Logistic回归分析。结果　胎膜早破 (PROM )、生后 4h内的pH值、动脉氧分压、生后 3d内最低二氧化碳分压、生后第 1周超声发现脑室周围强回声团 (PVE)的OR值分别为 2 383、3 2 77、3 76 9、3 96 5、1 931(P <0 0 1)。建立的早产儿PVL主效应模型为Logit(P) =β0 +0 897PROM - 1 346PaO2 - 1 2 78pH - 1 4 6 7PaCO2 +0 792PVE(χ2 =2 1 378,P =0 0 0 1)。结论　PROM、低氧血症、酸中毒、低碳酸血症、PVE为早产儿PVL的高危因素。     

Amplitude-integrated electroencephalography in preterm infants with cystic periventricular leukomalacia

Aim

This study aimed to assess amplitude-integrated electroencephalography (aEEG) findings in preterm infants with cystic periventricular leukomalacia (cPVL) in the early neonatal period.

Methods

We analyzed five infants with cPVL, whose gestational age was between 27 and 30 weeks, and 15 matched control infants. Two-channel (C3-O1 and C4-O2) aEEG was obtained by digital conversion from a conventional electroencephalogram, which was recorded at days 0-5, 6-13, and 21-34 in each infant. We evaluated the averaged two-channel values of several measurements using visual and quantitative analyses.

Results

Infants with cPVL had a significant higher maximal upper-margin amplitude value, with a median of 47.5 μV (range of 42.5-60) compared with the control infants (median, 33.8; range, 23.8-50) in the second visual-analysis record. Infants with cPVL also had a significantly higher mean upper-margin amplitude value, with a median of 18.8 μV (range, 17.7-23.2) compared with the control infants (median, 16.3; range, 10.3-19.0) in the second quantitative-analysis record.

Conclusions

We demonstrated that the upper-margin amplitude of aEEG in infants with cPVL was significantly higher than that in the control infants at 6-13 days after birth.     

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??Abstract:Objective??Using the skill of head ultrasound to make an early diagnosis for preterm infants with periventricular leukomalacia??PVL????analyze some related risk factors which may result in PVL. Methods??Between Jan. 2006 and Jun. 2009??443 preterm infants were chosen?? who were born in Anhui Provincial Children’s Hospital. All subjects were divided into PVL group??125?? and non PVL group??318????non Cystic PVL group??116?? and Cystic PVL group??9?? by different grades of PVL. The factors of PVL were analyzed by Backward Stepwise Logistic regression. Results??Univariate factor analysis showed?? the difference was significant ??P < 0.05 or P < 0.01??among gestational age?? birth weight?? delivery pattern?? hypothermia?? apnea?? blood sugar?? myocardial enzyme?? postnatal infection?? cAMP receptor protein and albumin between PVL group and non PVL group. Multiple factors Logistic regression showed?? low birth weight and incidence of uterine-incision delivery?? postnatal infection?? higher level of myocardial enzyme and albumin were risk factors of PVL?? and postnatal infection was risk factor of cystic PVL. Conclusion??Low birth weight?? spontaneous delivery?? postnatal infection and high levels of albumin and myocardial enzyme are risk factors of PVL. Preterm infants with postnatal infection have higher incidence of cystic PVL.     

早产儿脑室周围白质软化的影像学研究进展

脑室周围白质软化(PVL)是早产儿脑损伤的主要形式,包括囊性和弥漫性PVL.近年来其发病率有逐渐增高趋势,已成为影响早产儿生存质量及导致小儿脑瘫的主要疾病.因早产儿PVL缺乏特异的临床表现,故其诊断必须依赖于影像学检查.B超是目前确诊PVL最常用的检测手段,但其漏诊率较高;常规磁共振成像对评价PVL的脑损伤程度及预后判定具有重要意义,但在早期,特别是对弥漫性PVL也有其局限性;而弥散加权成像作为一种新型的检测技术,弥补了B型超声及常规磁共振成像的不足,为弥漫性PVL早期诊断提供了有价值的影像学信息.     

Patent ductus arteriosus and cystic periventricular leucomalacia in preterm infants

AIM: To test the association between early disturbances in hemodynamics induced by left-to-right shunting through the duct and cystic periventricular leucomalacia. PATIENTS: Forty-six preterm infants (27-32 wk) admitted to the neonatal intensive care unit with risk criteria. METHODS: Patent ductus arteriosus was evaluated on days 1 and 4, and was significant (sPDA) in cases of absent or reversed end diastolic flow in the subductal aorta. Resistance index was measured in the anterior cerebral artery and in the subductal aorta. MAIN OUTCOME: Diagnosis of cystic periventricular leucomalacia between day 10 and day 50. RESULTS: The 12 infants who developed cystic periventricular leucomalacia were compared with those who did not. On day 1, sPDA was more frequent (64% vs 26%; p = 0.03) in the cystic periventricular leucomalacia group, left ventricular output was higher (median = 341 vs 279 ml kg-1.min-1; p = 0.005), and rescue surfactant was more frequently used (83% vs 47%; p = 0.03). This latter association was confirmed by multivariate analysis. Resistance index in the anterior cerebral artery was increased in cases of significant patent ductus arteriosus (p < 0.01) and was correlated with resistance index in the subductal aorta. CONCLUSION: On day 1 in this selected population, sPDA has an effect on blood flow velocity waveform in cerebral arteries and is associated with an increase in the emergence of cystic periventricular leucomalacia. This association could be casual rather than causal.     

Antecedents of periventricular haemorrhage in infants weighing 1250 g or less at birth.

Fifty infants who weighed 1250 g or less at birth were studied with serial real time cerebral ultrasound to evaluate the temporal relation of various perinatal factors to the onset and progression of periventricular haemorrhage (PVH). The significant antecedents of PVH were severe bruising at birth, low birthweight, short gestation, ratio of arterial oxygen pressure (PaO2) to fractional inspired oxygen (FiO2), and haematocrit on admission, hyaline membrane disease, assisted ventilation, pneumothorax, administration of tubocurarine, hypercapnia, hypoxaemia, and hypotension. Case control studies, in which infants with PVH at 26 weeks'' and 28 weeks'' gestation were compared with matched infants without PVH, confirmed that the antecedents identified were independent of gestational influences. A multivariate discriminant analysis for the antecedents of PVH showed that hyaline membrane disease, hypercapnia, and short gestation correctly classified presence or absence of PVH in 78% of the study group. A similar analysis comparing infants with germinal layer haemorrhage or intraventricular haemorrhage with those who developed intracerebral extension of haemorrhage showed that three factors found on admission (hypothermia, a low PaO2:FiO2 ratio, and severe bruising) combined to classify correctly 90% of the haemorrhages. Our data suggest that prevention of perinatal trauma and asphyxia as well as respiratory illness, especially hyaline membrane disease, and stabilisation of blood gas tensions, blood pressure, and haematocrit within the physiological range, are likely to be the most effective ways of preventing PVH in extremely preterm infants.     

Possible etiological factors in extensive periventricular leukomalacia of preterm infants

During a twelve-month period five cases of extensive periventricular leukomalacia (PVL) in preterm infants with a gestational age of 31-32 weeks were diagnosed by routine ultrasound screening of preterm infants. The perinatal courses and later development of these infants were compared with 12 other infants with a comparable gestational age born during the same time period. PVL babies were delivered more often by the vaginal route (p = 0.0034), and their mean highest serum total bilirubin value was significantly higher (p = 0.0054) than that of the control infants. The mean value of the highest blood pH during the first 72 hours of life was also significantly higher (p = 0.0311) in PVL babies than in control babies. On the basis of these results we speculate that in addition to ischaemia in the periventricular area, bilirubin toxicity may play an additional role in the severe damage seen in extensive periventricular leukomalacia.     

Preventing periventricular haemorrhage

Over the past two decades, the incidence of periventricular haemorrhage has decreased dramatically, mainly related to the introduction of endogenous surfactant and the use of antenatal steroids in preterm labour. Despite this, periventricular haemorrhage remains a major cause of morbidity and mortality in premature infants. As most occur within the first hours of birth, any intervention needs to be aimed at the late antenatal period or very early postnatal period. Many drug therapies have been tried such as vitamin K, vitamin E, ethamsylate, phenobarbital, indomethacin and tranexamic acid, as well as the use of fresh frozen plasma, late cord clamping and early volume expansion. At the present time, there is insufficient evidence to recommend any specific treatment for the prophylaxis of periventricular haemorrhage in the neonatal unit.     

早产儿囊性脑室周围白质软化症高危因素探讨

目的探讨早产儿囊性脑室周围白质软化症(cPVL)的高危因素。方法对cPVL(12例)与非cPVL早产儿(30例)进行回顾性研究,对多种围产期高危因素进行Logistic回归分析。结果胎膜早破、生后48 h内PaCO2<3.33 kPa(25 mm Hg)、生后4 h内pH<7.25、生后1周内发现脑室周围强回声的OR值分别为2.125、3.312、2.820和3.712(P<0.05或P<0.01)。结论胎膜早破、生后48 h内PaCO2<3.33 kPa、生后4 h内pH<7.25、生后1周内脑室周围有强回声为早产儿cPVL的高危因素。