Posthemorrhagic hydrocephalus and brain injury in the preterm infant: dilemmas in diagnosis and management

Automatic brain segmentation in preterm infants with post-hemorrhagic hydrocephalus using 3D Bayesian U-Net

Post‐hemorrhagic hydrocephalus (PHH) is a severe complication of intraventricular hemorrhage (IVH) in very preterm infants. PHH monitoring and treatment decisions rely heavily on manual and subjective two‐dimensional measurements of the ventricles. Automatic and reliable three‐dimensional (3D) measurements of the ventricles may provide a more accurate assessment of PHH, and lead to improved monitoring and treatment decisions. To accurately and efficiently obtain these 3D measurements, automatic segmentation of the ventricles can be explored. However, this segmentation is challenging due to the large ventricular anatomical shape variability in preterm infants diagnosed with PHH. This study aims to (a) propose a Bayesian U‐Net method using 3D spatial concrete dropout for automatic brain segmentation (with uncertainty assessment) of preterm infants with PHH; and (b) compare the Bayesian method to three reference methods: DenseNet, U‐Net, and ensemble learning using DenseNets and U‐Nets. A total of 41 T₂‐weighted MRIs from 27 preterm infants were manually segmented into lateral ventricles, external CSF, white and cortical gray matter, brainstem, and cerebellum. These segmentations were used as ground truth for model evaluation. All methods were trained and evaluated using 4‐fold cross‐validation and segmentation endpoints, with additional uncertainty endpoints for the Bayesian method. In the lateral ventricles, segmentation endpoint values for the DenseNet, U‐Net, ensemble learning, and Bayesian U‐Net methods were mean Dice score = 0.814 ± 0.213, 0.944 ± 0.041, 0.942 ± 0.042, and 0.948 ± 0.034 respectively. Uncertainty endpoint values for the Bayesian U‐Net were mean recall = 0.953 ± 0.037, mean  negative predictive value = 0.998 ± 0.005, mean accuracy = 0.906 ± 0.032, and mean AUC = 0.949 ± 0.031. To conclude, the Bayesian U‐Net showed the best segmentation results across all methods and provided accurate uncertainty maps. This method may be used in clinical practice for automatic brain segmentation of preterm infants with PHH, and lead to better PHH monitoring and more informed treatment decisions.

Neuroprotection offered by mesenchymal stem cells in perinatal brain injury: Role of mitochondria, inflammation, and reactive oxygen species

Preclinical studies have shown that mesenchymal stem cells have a positive effect in perinatal brain injury models. The mechanisms that cause these neurotherapeutic effects are not entirely intelligible. Mitochondrial damage, inflammation, and reactive oxygen species are considered to be critically involved in the development of injury. Mesenchymal stem cells have immunomodulatory action and exert mitoprotective effects which attenuate production of reactive oxygen species and promote restoration of tissue function and metabolism after perinatal insults. This review summarizes the present state, the underlying causes, challenges and possibilities for effective clinical translation of mesenchymal stem cell therapy.

Impaired neural differentiation and glymphatic CSF flow in the Ccdc39 rat model of neonatal hydrocephalus: genetic interaction with L1cam

Neonatal hydrocephalus affects about one child per 1000 births and is a major congenital brain abnormality. We previously discovered a gene mutation within the coiled-coil domain-containing 39 (Ccdc39) gene, which causes the progressive hydrocephalus (prh) phenotype in mice due to lack of ependymal-cilia-mediated cerebrospinal fluid (CSF) flow. In this study, we used CRISPR/Cas9 to introduce the Ccdc39 gene mutation into rats, which are more suitable for imaging and surgical experiments. The Ccdc39^prh/prh mutants exhibited mild ventriculomegaly at postnatal day (P)5 that progressed into severe hydrocephalus by P11 (P<0.001). After P11, macrophage and neutrophil invasion along with subarachnoid hemorrhage were observed in mutant brains showing reduced neurofilament density, hypomyelination and increased cell death signals compared with wild-type brains. Significantly more macrophages entered the brain parenchyma at P5 before hemorrhaging was noted and increased expression of a pro-inflammatory factor (monocyte chemoattractant protein-1) was found in the cortical neural and endothelial cells in the mutant brains at P11. Glymphatic-mediated CSF circulation was progressively impaired along the middle cerebral artery from P11 as mutants developed severe hydrocephalus (P<0.001). In addition, Ccdc39^prh/prh mutants with L1 cell adhesion molecule (L1cam) gene mutation, which causes X-linked human congenital hydrocephalus, showed an accelerated early hydrocephalus phenotype (P<0.05-0.01). Our findings in Ccdc39^prh/prh mutant rats demonstrate a possible causal role of neuroinflammation in neonatal hydrocephalus development, which involves impaired cortical development and glymphatic CSF flow. Improved understanding of inflammatory responses and the glymphatic system in neonatal hydrocephalus could lead to new therapeutic strategies for this condition.

This article has an associated First Person interview with the joint first authors of the paper.

Summary: Glymphatic CSF circulation and development of the cerebral cortex are impaired in our new genetic rat model of neonatal hydrocephalus with the onset of parenchymal inflammation and hemorrhage.

Changes in Cerebral Oxygenation in Preterm Infants With Progressive Posthemorrhagic Ventricular Dilatation

BACKGROUND

Optimal timing of intervention in neonatal progressive posthemorrhagic hydrocephalus is often a difficult decision. Unchecked hydrocephalus can lead to irreversible brain injury through impaired perfusion, while placement of a shunt is not without long-term morbidity. The purpose of this study was to assess the use of near-infrared spectroscopy to measure changes in regional cerebral oxygen saturation as an indicator of cerebral perfusion in infants with progressive posthemorrhagic ventricular dilatation.

METHODS

Near-infrared spectroscopy was used to measure regional cerebral oxygen saturation for more than a one-hour period in infants within 24 hours of cranial ultrasound. Simultaneous pulse oximetry was recorded and oxygen extraction was calculated. Ventricular size was measured by ultrasound using the frontal-occipital horn ratio and compared with average oxygen saturation and oxygen extraction. Statistical analysis was done using the Spearman rank test and analysis of variance.

RESULTS

Ventricular measurements were made in 20 very low birth weight premature infants with periventricular-intraventricular hemorrhage and 12 infants with normal ultrasound scans. Ventricular dilatation was associated with lower cerebral oxygen saturation and higher oxygen extraction (P < 0.001). Progressive ventricular dilatation was inversely related to changes in cerebral oxygen saturation (P < 0.001).

CONCLUSIONS

Progressive posthemorrhagic ventricular dilatation is associated with a significant decrease in cerebral oxygenation and increase in oxygen extraction suggesting a decrease in cerebral perfusion. Near-infrared spectroscopy could potentially provide additional clinical information to assist in determining optimal timing of surgical intervention in preterm infants with progressive ventricular enlargement.

Evaluating Affordable Cranial Ultrasonography in East African Neonatal Intensive Care Units

Neuroimaging is a valuable diagnostic tool for the early detection of neonatal brain injury, but equipment and radiologic staff are expensive and unavailable to most hospitals in developing countries. We evaluated an affordable, portable ultrasound machine as a quantitative and qualitative diagnostic tool and to establish whether a novice sonographer could effectively operate the equipment and obtain clinically important information. Cranial ultrasonography was performed on term healthy, pre-term and term asphyxiated neonates in Rwandan and Kenyan hospitals. To evaluate the detection of ventriculomegaly and compression injuries, we measured the size of the lateral ventricles and corpus callosum. The images were also assessed for the presence of other cerebral abnormalities. Measurements were reliable across images, and cases of clinically relevant ventriculomegaly were detected. A novice sonographer had good-to-excellent agreement with an expert. This study demonstrates that affordable equipment and cranial ultrasound protocols can be used in low-resource settings to assess the newborn brain.

Timing of external ventricular drainage and neurodevelopmental outcome in preterm infants with posthemorrhagic hydrocephalus

OBJECTIVE

To delineate the impact of early (≤ 25 days of life) versus late (> 25 days) external ventricular drainage (EVD) on the neurodevelopmental outcome of preterm infants with posthemorrhagic hydrocephalus (PHH) following intraventricular hemorrhage (IVH).

METHODS

We retrospectively categorized 32 premature infants with PHH into two groups according to whether they underwent early (n = 10) or late (n = 22) EVD. We administered the Battelle Developmental Inventory II and a neuromotor examination (median age, 73 months, range: 29-100).

RESULTS

In adjusted comparisons, early EVD was associated with better scores than late EVD in adaptive (79 ± 22.6 vs. 58.8 ± 8.1, P = .01), personal social (90.7 ± 26 vs. 67.3 ± 15.9, P = .02), communication (95.4 ± 27.5 vs. 69.6 ± 20.5, P = .04) and cognitive (78.9 ± 24.4 vs. 60.7 ± 11.5, P = .055) functions. Three (30%) early EVD infants had severe (<2.5 standard deviation) cognitive disability compared to 18 (82%) late EVD infants (P = .03). The incidences of cerebral palsy and neurosurgical complications were equal for the two groups. Subgroup analyses suggested that early EVD was beneficial in infants with original grade III IVH (n = 15, P < 0.05), but that it had no beneficial effects in infants with prior parenchymal injury (n = 17, P = NS).

CONCLUSION

In this small retrospective series, early EVD is associated with lower rates of cognitive, communication and social disabilities than later EVD in infants with PHH without prior parenchymal injury. A randomized prospective trial is warranted.

Biomarkers in neonatal posthemorrhagic hydrocephalus

Posthemorrhagic hydrocephalus (PHH) is a rare but serious outcome among premature babies in the NICU, with consequences including mortality and severe neurodevelopmental disabilities. The causes of PHH are still not entirely understood, and its prevention and treatment are controversial. Various cerebrospinal fluid biomarkers have been studied in infants with PHH in order to recognize the causes, diagnose brain injury, and predict neurodevelopmental outcomes. This systematic review summarizes studies on biomarkers of extracellular matrix activity, fibrinolysis/coagulation, hypoxia/cell death, and inflammation in the cerebrospinal fluid of infants with PHH.

Neurodevelopmental outcome of post-hemorrhagic ventricular dilatation at 12 and 24 months corrected age with high-threshold therapy

BACKGROUND

The management of post-hemorrhagic hydrocephalus remains a discussion. We describe the neurodevelopmental outcome at the corrected age of 12 and 24 months of infants with PHVD treated with high-threshold therapy.

OBJECTIVE

To describe, and compare the neurodevelopmental outcome of a cohort of premature infants with grade III or IV intraventricular hemorrhage with or without development of PHVD.

METHODS

Retrospective chart and image review of all IVH grade III and IV infants admitted to the department of Neonatology of the Academic Medical Center, Amsterdam, the Netherlands between January 1999 and December 2006. A standardized neurodevelopmental examination was performed at the corrected ages of 12 and 24 months.

RESULTS

In total, 118 cases with IVH were identified. IVH grade III: n = 63, mean gestational age (GA): 28 weeks (SD 2.3), median birth weight (BW): 1130 g (range 908-1460 g); IVH IV: n = 31, mean GA: 28 weeks (SD 2.4), median BW: 1105 g (range 925-1230 g). Grade III and IV cases developed PHVD in 75% versus 42% respectively. Abnormal outcome in IVH III patients mainly occurred in cases with PHVD (12 months: 47% abnormal, 24 months: 64% abnormal). In the IVH IV cases, outcome was comparable with or without PHVD. Developmental delay was more pronounced at 24 months.

CONCLUSION

Mainly IVH III cases developed PHVD. Comparing our results with the literature neurodevelopmental outcome was poorer with our high-threshold therapy.

Ultrasound measurements of the lateral ventricles in neonates: why, how and when? A systematic review

Germinal matrix-intraventricular haemorrhage and subsequent post-haemorrhagic ventricular dilatation (PHVD) are frequently encountered complications in preterm neonates. As progressive dilatation of the lateral ventricles may be associated with elevated intracranial pressure, ultrasound measurements of ventricular size play a major role in the evaluation of neonates at risk of ventricular dilatation as well as in assessing the effect of intervention for PHVD. A systematic search was carried out in Medline and Embase to identify neonatal and foetal ultrasound studies on lateral ventricular size. This review presents an overview of the available data concerning neonatal reference values for lateral ventricular size, the influence of gender, ventricular asymmetry and the effect of the mode of delivery on the phenomenon of ventricular reopening following birth.

CONCLUSION

Serial cranial ultrasound measurements of the lateral ventricles play a key role in the early recognition and therapeutic evaluation of post-haemorrhagic ventricular dilation and can be of prognostic value in neonates with ventricular dilatation.

Intracranial hemorrhage in the preterm infant: understanding it, preventing it

New discoveries in neonatal imaging, cerebral monitoring, and hemodynamics, and greater understanding of inflammatory and genetic mechanisms involved in intracranial hemorrhage (ICH) in the preterm infant are creating opportunities for innovative early detection and prevention approaches. This article covers the spectrum of ICH in the preterm infant, including germinal matrix intraventricular hemorrhage, its complications, and associated phenomena, such as the emerging role of cerebellar hemorrhage. The overall aim of this article is to review the current knowledge of the mechanisms, diagnosis, outcome, and management of preterm ICH; to revisit the origins from which they develop; and to discuss future expectations.

Diuretics in pediatrics : current knowledge and future prospects

This review summarizes current knowledge on the pharmacology, pharmacokinetics, pharmacodynamics, and clinical application of the most commonly used diuretics in children. Diuretics are frequently prescribed drugs in children. Their main indication is to reduce fluid overload in acute and chronic disease states such as congestive heart failure and renal failure. As with most drugs used in children, optimal dosing schedules are largely unknown and empirical. This is undesirable as it can potentially result in either under- or over-treatment with the possibility of unwanted effects. The pharmacokinetics of diuretics vary in the different pediatric age groups as well as in different disease states. To exert their action, all diuretics, except spironolactone, have to reach the tubular lumen by glomerular filtration and/or proximal tubular secretion. Therefore, renal maturation and function influence drug delivery and consequently pharmacodynamics. Currently advised doses for diuretics are largely based on adult pharmacokinetic and pharmacodynamic studies. Therefore, additional pharmacokinetic and pharmacodynamic studies for the different pediatric age groups are necessary to develop dosing regimens based on pharmacokinetic and pharmacodynamic models for all routes of administration.

Hydrocephalus after intraventricular hemorrhage in preterm and low–birth weight infants: analysis of associated risk factors for ventriculoperitoneal shunting

BACKGROUND

Intraventricular hemorrhage and posthemorrhagic hydrocephalus are common causes of neonatal morbidity and mortality among preterm and low-birth weight infants (PT-LBWIs). Clinical management of posthemorrhagic hydrocephalus (PHH) is difficult and not well standardized. In this study, we aimed to determine the incidence of hydrocephalus after intraventricular hemorrhage (IVH) and the associated risk factors for ventriculoperitoneal (V-P) shunting in PT-LBWIs. We also aimed to identify the medical-care practices for these babies.

METHODS

We reviewed the medical records of 42 babies with IVH diagnosed by cranial ultrasonography (classification of Papile et al, J Pediatr 1978;92:529-34). We compared 11 babies who required a V-P shunt with the 31 control subjects who did not require a V-P shunt or who died before discharge with respect to risk factors involved in V-P shunting. Maternal, perinatal, and neonatal risk factors, and therapies for IVH and PHH were studied as the V-P shunt-associated risk factors.

RESULTS

The mean gestational age studied was 28.9 +/- 2.7 weeks, and the mean birth weight was 1164 +/- 391 g. This study revealed an incidence of 26% of PHH in PT-LBWIs with IVH. The most important risk factor for V-P shunt was found to be the severity of IVH (P < .05). Late gestational age and the time of IVH were found to be significant as well (P < .05). The length of hospitalization was found to be longer in patients with V-P shunt (P < .05). Therapies used for IVH and/or PHH were not significant as a risk factor for V-P shunt. In addition, the mortality rate was found to be 38% for all patients with IVH.

CONCLUSION

Intraventricular hemorrhage in PT-LBWIs remains a significant problem, particularly when it is associated with PHH leading to long-term neurological impairment and decreased survival rate.

CSF removal in infantile posthemorrhagic hydrocephalus results in significant improvement in cerebral hemodynamics

Rational intervention in infants with posthemorrhagic hydrocephalus (PHH) would be facilitated greatly by bedside measure of impaired cerebral perfusion, as there is substantial evidence that impaired perfusion and oxidative metabolism contribute to irreversible brain injury in hydrocephalus. Near-infrared spectroscopy (NIRS) measures changes in the cerebral concentration of oxygenated and deoxygenated hemoglobin and oxidized cytochrome oxidase at the bedside of infants continuously and noninvasively. The total hemoglobin and the hemoglobin difference signal are derived from the sum and difference, respectively, of oxygenated and deoxygenated hemoglobin. Changes in total hemoglobin reflect changes in cerebral blood volume; our previous work has shown that changes in hemoglobin difference signal reflect changes in cerebral blood flow. We hypothesized that cerebrospinal fluid (CSF) removal in infants with PHH would result in significant increases in cerebral perfusion, cerebral blood volume, and oxidative metabolism, as measured by NIRS. Continuous NIRS recordings were performed during CSF removal on 16 infants with PHH. There was a statistically significant increase in oxygenated hemoglobin (p < 0.001), total hemoglobin (p = 0.001), and hemoglobin difference signal (p = 0.006), but not oxidized cytochrome oxidase, accompanying CSF removal. There was no significant correlation between either the volume of CSF removed (in milliliters per kilogram body weight) or the opening pressure and the change in any of the measured or calculated NIRS signals. These findings demonstrate the pronounced effect of CSF removal on cerebral perfusion in infants with PHH. NIRS may be a useful technique to detect impending cerebral ischemia in such infants and thereby provide a means to guide the rational management of PHH.

Germinal matrix-intraventricular hemorrhage in the premature newborn: management and outcome

Germinal matrix-intraventricular hemorrhage (GMH-IVH) in the premature newborn results from rupture of fragile capillaries in the germinal matrix. Its pathogenesis is multifactorial and relates principally to a pressure-passive cerebral circulation, fluctuations in cerebral blood flow, and derangements of coagulation and fragility of the germinal matrix microvasculature. Several interventions have beneficial effects for prevention of GMH-IVH. Outcome after GMH-IVH relates largely to the severity of hemorrhage, the extent of hemorrhagic and ischemic parenchymal involvement, and complications (e.g., posthemorrhagic hydrocephalus). Even in the absence of neuroimaging abnormalities, VLBW infants have a high incidence of academic and behavioral problems which persist into adolescence and early adulthood.

Ultrasound grading of cerebral ventricular dilatation in preterm neonates

OBJECTIVE

To compare three grading systems previously described for the measurement of cerebral ventricular dilatation in preterm neonates using ultrasound scans and then to compare these with expert clinical judgement.

METHODS

Eighty-one preterm neonates <1500 g birthweight or < 32 weeks' gestation, with normal, mild, moderate or severely dilated ventricles recorded predominantly during the first 2 weeks of life were selected to ensure a broad representation of ventricular size. Their cranial ultrasound scans obtained nearest to 6 weeks of age were studied. The ventricular index, the diagonal width in the coronal plane and the ventricular height in the parasagittal plane were measured adjacent to the foramen of Monro and were used to grade the degree of dilatation. In 20 of these neonates, this grading was compared with grading based on expert clinical judgement.

RESULTS

Grading according to the ventricular index defined 79% of the scans as normal. However, only 44% and 39% were considered to be normal according to vertical height and diagonal width, respectively. There was a high level of correlation between expert clinical judgement and grading based on ventricular height measurement (r = 0.812; area under receiver operating characteristic (ROC) curve = 0.922) and the diagonal width (r = 0.806; area under ROC curve = 0.935). Ventricular index correlated poorly with clinical judgement (r = 0.298; area under ROC curve = 0.604).

CONCLUSIONS

The measurement of ventricular height and the measurement of diagonal width correlated well with expert clinical judgement. The ventricular index correlated poorly and was less sensitive to mild dilatation. There was no correlation between the ventricular index and the other two measures. The ventricular height and the diagonal width are more appropriate for assessing ventricular dilatation in preterm neonates.

Intracranial pressure changes during intermittent CSF drainage

Premature very-low-birth-weight infants with posthemorrhagic hydrocephalus are often managed with intermittent cerebrospinal fluid drainage from a ventricular reservoir. There are little data regarding intracranial pressure changes during intermittent drainage to determine the amount and frequency of cerebrospinal fluid removal or to determine the correct resistance of future programmable shunts. The objective of this study was to determine the feasibility of using a commercially available intracranial pressure transducer to measure changes in pressure associated with this procedure. Continuous intracranial pressure was measured in three infants with a transducer placed at the time of ventricular reservoir insertion. Daily reservoir taps began 48 hours after placement and intracranial pressure was monitored for 7 days. Intracranial pressure before the initial tap was comparable to levels previously reported as normal. The daily removal of 10 cc/kg of cerebrospinal fluid was sufficient to lower intracranial pressure below baseline, however it was associated with wide swings in pressure and, in one patient, sustained negative pressure. The use of direct intracranial pressure monitoring may be useful in determining the optimal amount and frequency of cerebrospinal drainage from infants with posthemorrhagic hydrocephalus managed with a ventricular reservoir, as well as determining resistance settings of subsequent programmable shunts.

Intracranial pressure and cerebral blood flow velocity in preterm infants with posthaemorrhagic ventricular dilatation

AIM

To determine the volume of cerebrospinal fluid (CSF) that should be tapped in preterm infants with posthaemorrhagic ventricular dilatation as guided by intracranial pressure (ICP) and cerebral blood flow velocity (CBFV).

METHODS

The total number of measurements was 106 in 22 infants. Birth weights ranged from 630 to 2050 g, gestational age from 24.5 to 30.3 weeks, and age at insertion from 12 to 67 days. A subcutaneous ventricular catheter reservoir for repetitive CSF drainage was placed when the diameter of a ventricle was > 4 mm above the 97th centile. A volume of 5 ml/kg body weight was removed twice daily. ICP and CBFV were determined before and after CSF tapping.

RESULTS

If the ICP after tapping exceeded 7 cm H(2)O, tapping did not result in a significant improvement in CBFV. If the ICP before tapping was less than 6 cm H(2)O, tapping also had no effect on CBFV. Longitudinal studies in individual infants showed a slight correlation between ICP and CBFV.

CONCLUSION

Volume of repetitive CSF drainage in preterm infants with posthaemorrhagic ventricular dilatation guided by ICP and CBFV may be a useful technique. An ICP of about 6 cm H(2)O is the cut off point for CSF drainage.

Multilocular hydrocephalus: ultrasound studies of origin and development

Multilocular hydrocephalus is a complication of neonatal hydrocephalus. Its main feature is the presence of multiple cysts inside the ventricles, which requires a specific therapeutic approach. The case of a preterm infant with intracranial hemorrhage grade II-III and central nervous system infection is reported. The cysts developed at the subependymal layer in the posterior area of the patient's thalamus. Their growth and development were charted by ultrasound imaging for several weeks. These types of cysts may grow to occupy the totality of the lateral ventricles, isolating the temporal horns. Of all the reviewed pathogenic mechanisms, we support the hypothesis of an inflammatory vasculitis at the subependymal level, with the subsequent infarct giving rise to the cysts. The osmotic pressure within the cavities, rather than intraventricular fluid, would account for the enlargement of the cysts.

Diuretic therapy for newborn infants with posthemorrhagic ventricular dilatation

BACKGROUND

Intraventricular hemorrhage remains a serious complication of premature birth and post hemorrhagic hydrocephalus still has no satisfactory treatment. Acetazolamide and furosemide, which both reduce the production of cerebrospinal fluid, have been suggested as non-invasive therapies to reduce hydrocephalus and the need for ventriculo-peritoneal (V-P) shunting.

OBJECTIVES

The aim of this review was to determine whether the use of acetazolamide and furosemide improves outcome, especially shunt dependence, in infants developing post-hemorrhagic ventricular dilatation.

SEARCH STRATEGY

The standard search strategy of the Cochrane Collaboration was used.

SELECTION CRITERIA

Randomised, or quasi-randomised trials, of acetazolamide and/or furosemide compared with standard therapy in infants with IVH or post-hemorrhagic ventricular dilatation

DATA COLLECTION AND ANALYSIS

Data were extracted independently by each author and were analysed by the standard methods of the Cochrane Collaboration using relative risk (RR) and risk difference (RD), a fixed effect model and sensitivity analyses where appropriate.

MAIN RESULTS

There were two eligible trials: one randomized 16 infants and the other, 177. Neither showed a decreased risk for V-P shunt or for V-P shunt or death associated with acetazolamide and furosemide therapy. The larger trial showed that acetazolamide and furosemide treatment resulted in a borderline increase in the risk for motor impairment at one year (RR 1.27, CI 1.02 to 1.58; RD 0.16, CI 0.02 to 0.31), but did not significantly affect the risk for the combined outcome of delay, disability or motor impairment among survivors, or the risk of the combined outcome of death, delay, disability or impairment at one year. The larger trial showed that diuretic treatment increased the risk for nephrocalcinosis (RR 5.31, CI 1.90 to 14.84; RD 0.19, CI 0.09 to 0.29); meta-analysis confirmed this result.

REVIEWER'S CONCLUSIONS

Acetazolamide and furosemide therapy is neither effective nor safe in treating post hemorrhagic ventricular dilatation. Acetazolamide and furosemide cannot be recommended as therapy for post hemorrhagic hydrocephalus.

Periventricular leukomalacia: an important cause of visual and ocular motility dysfunction in children

The immature visual system in infants born preterm is vulnerable to adverse events during the perinatal period. Periventricular leukomalacia affecting the optic radiation has now become the principal cause of visual impairment and dysfunction in children born prematurely. Visual dysfunction is characterized by delayed visual maturation, subnormal visual acuity, crowding, visual field defects, and visual perceptual-cognitive problems. Magnetic resonance imaging is the method of choice for diagnosing this brain lesion, which is associated with optic disk abnormalities, strabismus, nystagmus, and deficient visually guided eye movements. Children with periventricular leukomalacia may present to the ophthalmologist within a clinical spectrum from severe cerebral visual impairment in combination with cerebral palsy and mental retardation to only early-onset esotropia, normal intellectual level, and no cerebral palsy. Optimal educational and habilitational strategies need to be developed to meet the needs of this group of visually impaired children.