Ultrasound lineal measurements predict ventricular volume in posthaemorrhagic ventricular dilatation in preterm infants

Ultrasonographic Estimation of Ventricular Volume in Infants Born Preterm with Posthemorrhagic Ventricular Dilatation: A Nested Substudy of the Randomized Controlled Early Versus Late Ventricular Intervention Study (ELVIS) Trial

OBJECTIVE

To study the potential role of ventricular volume (VV) estimation in the management of posthemorrhagic ventricular dilatation related to the need for ventriculoperitoneal (VP)-shunt insertion and 2-year neurodevelopmental outcome in infants born preterm.

STUDY DESIGN

We included 59 patients from the Early vs Late Ventricular Intervention Study from 4 participating centers. VV was manually segmented in 209 3-dimensional ultrasound scans and estimated from 2-dimensional ultrasound linear measurements in a total of 1226 ultrasounds. We studied the association of both linear measurements and VV to the need for VP shunt and 2-year neurodevelopmental outcome in the overall cohort and in the 29 infants who needed insertion of a reservoir. We used general estimating equations to account for repeated measures per individual.

RESULTS

Maximum pre-reservoir VV (β coefficient = 0.185, P = .0001) and gestational age at birth (β = -0.338; P = .0001) were related to the need for VP shunt. The estimated optimal single VV measurement cut point of 17 cm3 correctly classified 79.31% with an area under the curve of 0.76 (CI 95% 0.74-0.79). Maximum VV (β = 0.027; P = .012) together with VP shunt insertion (β = 3.773; P = .007) and gestational age (β = -0.273; P = .0001) were related to cognitive outcome at 2 years. Maximum ventricular index and anterior horn width before reservoir insertion were independently associated with the need of VP shunt and the proposed threshold groups in the Early vs Late Ventricular Intervention Study trial were associated with long-term outcome.

CONCLUSIONS

Pre-reservoir VV measurements were associated with the need for VP-shunt insertion and 2-year cognitive outcome among infants born preterm with posthemorrhagic ventricular dilatation.

TRIAL REGISTRATION

ISRCTN43171322.

Spontaneous resolution of post-hemorrhagic ventricular dilatation in preterm newborns and neurodevelopment

BACKGROUND

We investigated the temporal evolution of post-hemorrhagic ventricular dilatation (PHVD) and compared neurodevelopmental impairments (NDI) in newborns with (Group 1) spontaneous resolution of PHVD, (Group 2) persistent PHVD without neurosurgical intervention, and (Group 3) progressive PHVD receiving neurosurgical intervention.

METHODS

A multicenter retrospective cohort study of newborns born at ≤34 weeks with PHVD (ventricular index [VI] >97th centile for gestational age and anterior horn width [AHW] >6 mm) from 2012 to 2020. Severe NDI was defined as global developmental delay or cerebral palsy GMFCS III-V at 18 months.

RESULTS

Of 88 survivors with PHVD, 39% had a spontaneous resolution, 17% had persistent PHVD without intervention, and 44% had progressive PHVD receiving intervention. The median time between PHVD diagnosis and spontaneous resolution was 14.0 days (IQR 6.8-32.3) and between PHVD diagnosis and first neurosurgical intervention was 12.0 days (IQR 7.0-22.0). Group 1 had smaller median maximal VI (1.8, 3.4, 11.1 mm above p97; p < 0.001) and AHW (7.2, 10.8, 20.3 mm; p < 0.001) than Groups 2 and 3. Neurodevelopmental outcome data were available for 82% of survivors. Group 1 had reduced severe NDI compared to Group 3 (15% vs 66%; p < 0.001).

CONCLUSION

Newborns with PHVD without spontaneous resolution are at higher risk for impairments despite neurosurgical interventions, which may be due to larger ventricular dilatation.

IMPACT

The natural evolution of post-hemorrhagic ventricular dilatation (PHVD) and developmental implications of spontaneous resolution are not well established. In this study, approximately one in three newborns with PHVD experienced spontaneous resolution and this subset of newborns had reduced rates of neurodevelopmental impairments. More prominent ventricular dilatation was associated with reduced rates of spontaneous resolution and increased rates of severe neurodevelopmental impairment among newborns with PHVD. Understanding clinically relevant time points in the evolution of PHVD and predictors of spontaneous resolution may help inform the discussion around the optimal timing for intervention and allow for more precise prognostication in this population.

Ultrasonographic evaluation of the early brain growth pattern in very low birth weight infants

BACKGROUND

Preterm infants develop smaller brain volumes compared to term newborns. Our aim is to study early brain growth related to perinatal factors in very low birth weight infants (VLBWI).

METHODS

Manual segmentation of total brain volume (TBV) was performed in weekly 3D-ultrasonographies in our cohort of VLBWI. We studied the brain growth pattern related to term magnetic resonance image (term-MRI).

RESULTS

We found different brain growth trajectories, with smaller brain volumes and a decrease in brain growth rate in those VLBWI who would later have an abnormal term-MRI (mean TBV 190.68 vs. 213.9 cm3; P = 0.0001 and mean TBV growth rate 14.35 (±1.27) vs. 16.94 (±2.29) cm3/week; P = 0.0001). TBV in those with normal term-MRI was related to gestational age (GA), being small for gestational age (SGA), sex, and duration of parenteral nutrition (TPN) while in those with abnormal term-MRI findings it was related to GA, SGA, TPN, and comorbidities. We found a deceleration in brain growth rate in those with ≥3 comorbidities.

CONCLUSIONS

An altered brain growth pattern in VLBWI who subsequently present worst scores on term-MRI is related to GA, being SGA and comorbidities. Early ultrasonographic monitoring of TBV could be useful to detect deviated patterns of brain growth.

IMPACT STATEMENT

We describe the brain growth pattern in very low birth weight infants during their first postnatal weeks. Brain growth may be affected in the presence of certain perinatal factors and comorbidities, conditioning a deviation of the normal growth pattern. The serial ultrasound follow-up of these at-risk patients allows identifying these brain growth patterns early, which offers a window of opportunity for implementing earlier interventions.

Intraparenchymal hemorrhage after serial ventricular reservoir taps in neonates with hydrocephalus and association with neurodevelopmental outcome at 2 years of age

OBJECTIVE

Decompressing the ventricles with a temporary device is often the initial neurosurgical intervention for preterm infants with hydrocephalus. The authors observed a subgroup of infants who developed intraparenchymal hemorrhage (IPH) after serial ventricular reservoir taps and sought to describe the characteristics of IPH and its association with neurodevelopmental outcome.

METHODS

In this multicenter, case-control study, for each neonate with periventricular and/or subcortical IPH, a gestational age-matched control with reservoir who did not develop IPH was selected. Digital cranial ultrasound (cUS) scans and term-equivalent age (TEA)-MRI (TEA-MRI) studies were assessed. Ventricular measurements were recorded prior to and 3 days and 7 days after reservoir insertion. Changes in ventricular volumes were calculated. Neurodevelopmental outcome was assessed at 2 years corrected age using standardized tests.

RESULTS

Eighteen infants with IPH (mean gestational age 30.0 ± 4.3 weeks) and 18 matched controls were included. Reduction of the ventricular volumes relative to occipitofrontal head circumference after 7 days of reservoir taps was greater in infants with IPH (mean difference -0.19 [95% CI -0.37 to -0.004], p = 0.04). Cognitive and motor Z-scores were similar in infants with and those without IPH (mean difference 0.42 [95% CI -0.17 to 1.01] and 0.58 [95% CI -0.03 to 1.2]; p = 0.2 and 0.06, respectively). Multifocal IPH was negatively associated with cognitive score (coefficient -0.51 [95% CI -0.88 to -0.14], p = 0.009) and ventriculoperitoneal shunt with motor score (coefficient -0.50 [95% CI -1.6 to -0.14], p = 0.02) after adjusting for age at the time of assessment.

CONCLUSIONS

This study reports for the first time that IPH can occur after a rapid reduction of the ventricular volume during the 1st week after the initiation of serial reservoir taps in neonates with hydrocephalus. Further studies on the use of cUS to guide the amount of cerebrospinal fluid removal are warranted.

Effects of early energy intake on neonatal cerebral growth of preterm newborn: an observational study

Current guidelines for preterm newborns recommend high energy nutrition soon after birth in order to limit growth retardation. However, long-term effects of this nutritional approach are still debated, and it has been demonstrated that cerebral growth depends on protein intake in early life. A negative impact of early high energy intake by parenteral nutrition (PN) has been reported for patients in critically ill conditions, observed in intensive care unit. We aimed at evaluating the impact of energy intake on cerebral growth in preterm neonates early in life. We included preterm newborns with gestational age < 32 weeks or birth weight (BW) < 1500 g. Measurement of cerebral structures was performed by cranial Ultrasonography (cUS) between 3 and 7 days of life (DOL, T0) and at 28 DOL (T1). We evaluated the relation between energy intake and cerebral growth in the first 28 DOL. We observed in 109 preterm newborns a significant (p < 0.05) negative correlation between energy intake received by PN and right caudate head growth (r = - 0.243*) and a positive correlation between total energy intake and transverse cerebellum diameter (r = 0.254*). Multivariate analysis showed that energy intake administered by enteral nutrition (EN), independently increased growth of left caudate head (β = 0.227*) and height cerebellar vermis (β = 0.415*), while PN independently affected growth of both right and left caudate head (β = - 0.164* and β = - 0.228*, respectively) and cerebellum transverse diameter (β = - 0.849*). The route of energy administration may exert different effects on cerebral growth in early life. High energy intake administered through EN seems to be positively correlated to cerebral growth; conversely, PN energy intake results in a poorer cerebral growth evaluated with cUS.

Automatic segmentation of ventricular volume by 3D ultrasonography in post haemorrhagic ventricular dilatation among preterm infants

To train, evaluate, and validate the application of a deep learning framework in three-dimensional ultrasound (3D US) for the automatic segmentation of ventricular volume in preterm infants with post haemorrhagic ventricular dilatation (PHVD). We trained a 2D convolutional neural network (CNN) for automatic segmentation ventricular volume from 3D US of preterm infants with PHVD. The method was validated with the Dice similarity coefficient (DSC) and the intra-class coefficient (ICC) compared to manual segmentation. The mean birth weight of the included patients was 1233.1 g (SD 309.4) and mean gestational age was 28.1 weeks (SD 1.6). A total of 152 serial 3D US from 10 preterm infants with PHVD were analysed. 230 ventricles were manually segmented. Of these, 108 were used for training a 2D CNN and 122 for validating the methodology for automatic segmentation. The global agreement for manual versus automated measures in the validation data (n = 122) was excellent with an ICC of 0.944 (0.874–0.971). The Dice similarity coefficient was 0.8 (± 0.01). 3D US based ventricular volume estimation through an automatic segmentation software developed through deep learning improves the accuracy and reduces the processing time needed for manual segmentation using VOCAL. 3D US should be considered a promising tool to help deepen our current understanding of the complex evolution of PHVD.

Ultrasonographic Estimation of Total Brain Volume: 3D Reliability and 2D Estimation. Enabling Routine Estimation During NICU Admission in the Preterm Infant

Objectives: The aim of this study is to explore if manually segmented total brain volume (TBV) from 3D ultrasonography (US) is comparable to TBV estimated by magnetic resonance imaging (MRI). We then wanted to test 2D based TBV estimation obtained through three linear axes which would enable monitoring brain growth in the preterm infant during admission. Methods: We included very low birth weight preterm infants admitted to our neonatal intensive care unit (NICU) with normal neuroimaging findings. We measured biparietal diameter, anteroposterior axis, vertical axis from US and MRI and TBV from both MRI and 3D US. We calculated intra- and interobserver agreement within and between techniques using the intraclass correlation coefficient and Bland-Altman methodology. We then developed a multilevel prediction model of TBV based on linear measurements from both US and MRI, compared them and explored how they changed with increasing age. The multilevel prediction model for TBV from linear measures was tested for internal and external validity and we developed a reference table for ease of prediction of TBV. Results: We used measurements obtained from 426 US and 93 MRI scans from 118 patients. We found good intra- and interobserver agreement for all the measurements. US measurements were reliable when compared to MRI, including TBV which achieved excellent agreement with that of MRI [ICC of 0.98 (95% CI 0.96-0.99)]. TBV estimated through 2D measurements of biparietal diameter, anteroposterior axis, and vertical axis was comparable among both techniques. We estimated the population 95% confidence interval for the mean values of biparietal diameter, anteroposterior axis, vertical axis, and total brain volume by post-menstrual age. A TBV prediction table based on the three axes is proposed to enable easy implementation of TBV estimation in routine 2D US during admission in the NICU. Conclusions: US measurements of biparietal diameter, vertical axis, and anteroposterior axis are reliable. TBV segmented through 3D US is comparable to MRI estimated TBV. 2D US accurate estimation of TBV is possible through biparietal diameter, vertical, and anteroposterior axes.

Early Protein Intake Influences Neonatal Brain Measurements in Preterms: An Observational Study

Introduction: To limit extrauterine growth restriction, recent guidelines on nutrition of preterm neonates recommended high protein intake since the first day of life (DOL). The impact of this nutritional strategy on the brain is still controversial. We aimed to evaluate the effects of protein intake on early cerebral growth in very low birth weight newborns.

Materials and Methods: We performed serial cranial ultrasound (cUS) scans at 3–7 DOL and at 28 DOL in very low birth weight newborns consecutively observed in the neonatal intensive care unit. We analyzed the relation between protein intake and cerebral measurements at 28 DOL performed by cUS.

Results: We enrolled 100 newborns (gestational age 29 ± 2 weeks, birth weight 1,274 ± 363 g). A significant (p < 0.05) positive correlation between enteral protein intake and biparietal diameter (r = 0.490^**), occipital–frontal diameter (r = 0.608^**), corpus callosum (length r = 0.293^*, genu r = 0.301^*), caudate head (right r = 0.528^**, left r = 0.364^**), and cerebellum (transverse diameter r = 0.440^**, vermis height r = 0.356^**, vermis width r = 0.377^**) was observed at 28 DOL. Conversely, we found a significant negative correlation of protein intake given by parenteral nutrition (PN) with biparietal diameter (r = −0.524^**), occipital–frontal diameter (r = −0.568^**), body of corpus callosum (r = −0.276^*), caudate head (right r = −0.613^**, left r = −0.444^**), and cerebellum (transverse diameter r = −0.403^**, vermis height r = −0.274^*, vermis width r = −0.462^**) at 28 DOL. Multivariate regression analysis showed that measurements of occipital–frontal diameter, caudate head, and cerebellar vermis at 28 DOL depend positively on protein enteral intake (r = 0.402^*, r = 0.305^*, and r = 0.271^*) and negatively by protein parenteral intake (r = −0.278^*, r = −0.488^*, and r = −0.342^*).

Conclusion: Brain development in neonatal life depends on early protein intake. High protein intake affects cerebral structures' measurements of preterm newborn when administered by PN. Positive impact on brain development encourages the administration of recommended protein intake mainly by enteral nutrition.

Two-dimensional ultrasound measurements vs. magnetic resonance imaging-derived ventricular volume of preterm infants with germinal matrix intraventricular haemorrhage

BACKGROUND

Post-haemorrhagic ventricular dilatation can be measured accurately by MRI. However, two-dimensional (2-D) cranial US can be used at the bedside on a daily basis.

OBJECTIVE

To assess whether the ventricular volume can be determined accurately using US.

MATERIALS AND METHODS

We included 31 preterm infants with germinal matrix intraventricular haemorrhage. Two-dimensional cranial US images were acquired and the ventricular index, anterior horn width and thalamo-occipital distance were measured. In addition, cranial MRI was performed. The ventricular volume on MRI was determined using a previously validated automatic segmentation algorithm. We obtained the correlation and created a linear model between MRI-derived ventricular volume and 2-D cranial US measurements.

RESULTS

The ventricular index, anterior horn width and thalamo-occipital distance as measured on 2-D cranial US were significantly associated with the volume of the ventricles as determined with MRI. A general linear model fitted the data best: ∛ventricular volume (ml) = 1.096 + 0.094 × anterior horn width (mm) + 0.020 × thalamo-occipital distance (mm) with R² = 0.831.

CONCLUSION

The volume of the lateral ventricles of infants with germinal matrix intraventricular haemorrhage can be estimated using 2-D cranial US images by application of a model.

Preterm brain injury: Germinal matrix-intraventricular hemorrhage and post-hemorrhagic ventricular dilatation

Germinal matrix hemorrhage and intraventricular hemorrhages (GMH-IVH) remain a common and clinically significant problem in preterm infants, particularly extremely preterm infants. A large GMH-IVH is often complicated by posthemorrhagic ventricular dilation (PHVD) or parenchymal hemorrhagic infarction and is associated with an increased risk of adverse neurologic sequelae. The widespread use of cranial ultrasonography since the early 1980s has shown a gradual decrease in the incidence of GMH-IVH and has helped with the identification of antenatal and perinatal risk factors and timing of the lesion. The increased use of magnetic resonance imaging (MRI) has contributed to more detailed visualization of the site and extent of the GMH-IVH. In addition, MRI has contributed to the awareness of associated white matter changes as well as associated cerebellar hemorrhages. Although GMH-IVH and PHVD still cannot be prevented, cerebrospinal fluid drainage initiated in the early stage of PHVD development seems to be associated with a better neurodevelopmental outcome. Further studies are underway to improve treatment strategies for PHVD and to potentially prevent and repair GMH-IVH and PHVD and associated brain injury. This chapter discusses the pathogenesis, incidence, risk factors, and management, including preventive measures, of GHM-IVH and PHVD.

Normal Cerebellar Growth by Using Three-dimensional US in the Preterm Infant from Birth to Term-corrected Age

Purpose To establish cross-sectional and longitudinal reference values for cerebellar size in preterm infants with normal neuroimaging findings and normal 2-year neurodevelopmental outcome by using cranial ultrasonography (US). Materials and Methods This prospective study consecutively enrolled preterm infants admitted to a neonatal intensive care unit from June 2011 to June 2014 with a birth weight of less than or equal to 1500 g and/or gestational age (GA) of less than or equal to 32 weeks. They underwent weekly cranial US from birth to term-equivalent age and magnetic resonance (MR) imaging at term-equivalent age. The infants underwent neurodevelopmental assessments at age 2 years with Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III). Patients with adverse outcomes (death or abnormal neuroimaging findings and/or BSID-III score of <85) were excluded. The following measurements were performed: vermis height, craniocaudal diameter, superior width, inferior width, vermis area, and transcerebellar diameter. Statistical analyses were conducted by using multilevel analyses. Results A total of 137 infants with a mean GA at birth of 29.4 weeks (range, 25-32 weeks) were included. Transcerebellar diameter increased by 1.04 mm per week on average; vermis height and craniocaudal diameter increased by 0.55 mm and 0.59 mm, respectively. Superior vermian width increased by an average of 0.45 mm, whereas inferior vermian width increased by an average of 0.51 mm per week. Vermis area was found to increase by 0.22 cm² per week on average. The sex effect was significant (female lower than male) for vermis height (P < .05), craniocaudal diameter (P < .05), inferior vermian width (P <. 05), and vermis area (P <. 05). Conclusion Cross-sectional and longitudinal reference values were established for cerebellar growth in preterm infants, which may be included in routine cranial US.

Bedside transcranial sonography monitoring in a patient with hydrocephalus post subarachnoid hemorrhage

Background

Development of hydrocephalus can occur after subarachnoid hemorrhage (SAH). Typically, it is diagnosed with computed tomography, CT, scan. However, transcranial sonography (TCS) can be used particularly in patients with craniotomy which removes the acoustic interference of the skull and allows a closer up visualization of brain structures through the skin.

Case presentation

We report a 73-year-old woman who was hospitalized for SAH and developed acute hydrocephalus requiring an external ventricular drain (EVD). In this patient, detection and monitoring of hydrocephalus was done and monitored with a small pocket-sized TCS device. Nine days after surgery, weaning of the EVD was attempted. Prior to EVD closure and removal, TCS showed a measurement of the 3rd ventricle at around 1.16 cm. On the third day, the patient deteriorated clinically and the TCS showed a dilated 3rd ventricle measuring 1.37 cm which correlated well with computed tomography and with clinical signs of active hydrocephalus as both her sensorium and communication were affected. Subsequently following EVD re-installation, on the next day, TCS showed that the 3rd ventricle dimension was reduced to 0.99 cm and the following day it went down to 0.69 cm.

Conclusions

Patients with SAH and in particular those with a craniotomy can be monitored easily at the bedside with hand-held TCS for the development and monitoring of hydrocephalus.