The accuracy of linear indices of ventricular volume in pediatric hydrocephalus: technical note

Evaluating Linear Heuristics for Ventricular Volume in Healthy Adults Using a Fully Automated Algorithm: Implications for Defining the Normal

BACKGROUND AND OBJECTIVES

Linear metrics for ventricular volume play a large role in the rapid, approximate evaluation of ventricular volume. In this article, we automatically extract linear measures of ventricular volume to explore their correlation with lateral ventricular volume (LVV) in the healthy adult population and comprehensively define normal values.

METHODS

We automatically extract Evans' ratio (ER), Frontal-Occipital Horn Ratio (FOHR), and anteroposterior lateral ventricle index (ALVI) from an open MRI data set of healthy adults ( https://brain-development.org/ixi-dataset/ ). Indices have been correlated with corresponding LVVs and lateral ventricular volumes divided by supratentorial brain volumes. Spearman rank correlation was used to compare strength of correlation.

RESULTS

ER shows correlation with lateral ventricle volume based on sex (r = 0.58; men, r = 0.65; women P < .001), including when controlling for supratentorial volume (r = 0.57; men, r = 0.63). ER did not profoundly correlate with age (r = 0.29, men; r = 0.35, women; P < .001) and seemed normally distributed around 0.25. ALVI showed strong correlation with LVV with only slight gender differences (r = 0.83, men; r = 0.84, women) and LVV to supratentorial cortical volume ratio (r = 0.9, men; r = 0.86, women). FOHR was also normally distributed around a value of 0.37 and showed moderate correlation with LVV (r = 0.68, men; r = 0.73, women) and LVV to supratentorial cortical volume ratio (r = 0.69, men; r = 0.74, women).

CONCLUSION

ALVI is a newer index with strong correlation with LVV and has strong potential for clinical use. Both FOHR and ER show moderate correlation with LVV. Reference values for linear estimates of ventricular volume may help clinicians better identify patients with pathological ventriculomegaly.

Comparison of surgical approaches and outcome for symptomatic pineal cysts: microscopic/endoscopic fenestration vs. stereotactic catheter implantation

PURPOSE

Treatment strategies for space-occupying/symptomatic pineal cysts (PC) are still up for debate. In this study we present PC management, outcome data and risk factors for recurrence after surgery, focusing on microscopic/endoscopic procedures vs. stereotactic catheter implantation as alternative treatment concept to permanently drain PC into ventricles/cisterns.

METHODS

This monocentric retrospective analysis included clinical data from all consecutive PC patients treated surgically between 2000 and 2022. Postoperative neurological and functional outcomes, along with perioperative complications, as well as time to PC recurrence and MR-morphological data were evaluated.

RESULTS

39 patients (median age 32.6 years, range: 5.1-71.6 years) were analyzed. Main presenting symptoms were headaches, visual impairment, and epileptic seizures. In 18 patients (46.2%) an enlarged ventricular system was preoperatively found with 7 patients (18.0%) suffering from occlusive hydrocephalus. 14 patients underwent microscopic/endosocopic surgery, in 25 cases stereotaxy was preferred. No complication was seen in the microsurgery/endoscopy group compared to one intracystic postoperative bleeding (2.6%) and two CSF leaks (5.1%) after stereotaxy (p = 0.5). Overall, clinical improvement and significant cyst volume reduction (p < 0.0001) was seen in all patients. Recurrent PC were seen in 23.1%, independent of surgical procedure (p = 0.2). In cases of recurrence, TTR was 25.2 ± 31.2 months. Male gender (p = 0.01), longer surgery time (p = 0.03) and preoperatively increased Evans index (EI) (p = 0.007) were significant risk factors for PC recurrence in multivariate analysis.

CONCLUSION

In patients suffering from PC, microsurgical and stereotactic approaches can improve clinical symptoms at low procedural risk, with equal extent of volume reduction. However, preoperative ventricular enlargement and EI values should be considered for optimal treatment planning to reduce recurrence.

Risk factors for domain-specific neurocognitive outcome in pediatric survivors of a brain tumor in the posterior fossa-Results of the HIT 2000 trial

BACKGROUND

Neurocognition can be severely affected in pediatric brain tumor survivors. We analyzed the association of cognitive functioning with radiotherapy dose, postoperative cerebellar mutism syndrome (pCMS), hydrocephalus, intraventricular methotrexate (MTX) application, tumor localization, and biology in pediatric survivors of a posterior fossa tumor.

METHODS

Subdomain-specific neurocognitive outcome data from 279 relapse-free survivors of the HIT-2000 trial (241 medulloblastoma and 38 infratentorial ependymoma) using the Neuropsychological Basic Diagnostic tool based on Cattell-Horn-Carroll's model for intelligence were analyzed.

RESULTS

Cognitive performance 5.14 years (mean; range = 1.52-13.02) after diagnosis was significantly below normal for all subtests. Processing speed and psychomotor abilities were most affected. Influencing factors were domain-specific: CSI-dose had a strong impact on most subtests. pCMS was associated with psychomotor abilities (β = -0.25 to -0.16) and processing speed (β = -0.32). Postoperative hydrocephalus correlated with crystallized intelligence (β = -0.20) and short-term memory (β = -0.15), age with crystallized intelligence (β = 0.15) and psychomotor abilities (β = -0.16 and β = -0.17). Scores for fluid intelligence (β = -0.23), short-term memory (β = -0.17) and visual processing (β = -0.25) declined, and scores for selective attention improved (β = 0.29) with time after diagnosis.

CONCLUSIONS

The dose of CSI was strongly associated with neurocognitive outcomes. Low psychomotor abilities and processing speed both in patients treated with and without CSI suggest a strong contribution of the tumor and its surgery on these functions. Future research therefore should analyze strategies to both reduce CSI dose and toxicity caused by other treatment modalities.

Prognostic factors for endoscopic third ventriculostomy success in hydrocephalus with myelomeningocele

PURPOSE

Myelomeningocele (MMC) is a prevalent neural tube closure defect often associated with hydrocephalus, necessitating surgical intervention in a significant proportion of cases. While ventriculoperitoneal shunting (VPS) has been a standard treatment approach, endoscopic third ventriculostomy (ETV) has emerged as a promising alternative. However, factors influencing the success of ETV in MMC patients remain uncertain. This retrospective observational study aimed to identify clinical and radiological factors correlating with a higher success rate of ETV in MMC patients.

METHODS

Medical records of MMC patients who underwent ETV at a tertiary care center between 2015 and 2021 were reviewed. Demographic, clinical, and radiological data were analyzed. ETV success was defined as the absence of further hydrocephalus treatment during follow-up.

RESULTS

Of 131 MMC patients, 21 met inclusion criteria and underwent ETV. The overall success rate of ETV was 57.1%, with a six-month success rate of 61.9%. Age ≤ 6 months was significantly associated with lower ETV success (25%) compared to older patients (76.9%) (OR: 0.1; 95% CI 0.005-2.006; p = 0.019). Radiological factors, including posterior fossa dimensions and linear indices, did not exhibit statistically significant associations with ETV success.

CONCLUSION

Age emerged as a significant factor affecting ETV success in MMC patients, with younger patients exhibiting lower success rates. Radiological variables did not significantly influence ETV outcomes in this study. Identifying predictors of ETV success in MMC patients is crucial for optimizing treatment strategies and improving patient outcomes.

Radiologically defined acute hydrocephalus in aneurysmal subarachnoid haemorrhage

BACKGROUND

Ventriculomegaly is common in aneurysmal subarachnoid haemorrhage (aSAH). An imaging measure to predict the need for cerebrospinal fluid (CSF) diversion may be useful. The bicaudate index (BCI) has been previously applied to aSAH. Our aim was to derive and test a threshold BCI above which CSF diversion may be required.

METHODS

Review of prospective registry. The derivation group (2009-2015) included WFNS grade 1-2 aSAH patients who deteriorated clinically, had a repeat CT brain and underwent CSF diversion. BCI was measured on post-deterioration CTs and the lower limit of the 95% confidence interval (95%CI) was the hydrocephalus threshold. In a separate test group (2016), in WFNS ≥ 2 patients, we compared BCI on diagnostic CTs with CSF diversion within 24 hours.

RESULTS

The derivation group (n = 62) received an external ventricular (n = 57, 92%) or lumbar drain (n = 5, 8%). Mean post-deterioration BCI was 0.19 (95%CI 0.17-0.22) for age ≤49 years, 0.22 (95%CI 0.20-0.23) for age 50-64 years and 0.24 (95%CI 0.22-0.27) for age ≥65 years. Hydrocephalus thresholds were therefore 0.17, 0.20 and 0.22, respectively. In the test group (n = 105), there was no significant difference in BCI on the diagnostic CT between good and poor grade patients aged ≤49 years (p = 0.31) and ≥65 years (p = 0.96). 30/66 WFNS ≥ 2 patients underwent CSF diversion, although only 15/30 (50%) exceeded BCI thresholds for hydrocephalus.

CONCLUSION

A significant proportion of aSAH patients may undergo CSF diversion without objective evidence of hydrocephalus. Our threshold values require further testing but may provide an objective measure to aid clinical decision making in aSAH.

Postoperative hydrocephalus is a high-risk lethal factor for patients with low-grade optic pathway glioma

OBJECTIVES

To explore the prognostic factors of patients with low-grade optic pathway glioma (OPG) and the optimal treatment to reduce the incidence of postoperative hydrocephalus.

PATIENTS AND METHODS

This single-center study retrospectively analyzed data from 66 patients with OPGs who underwent surgery. The patients were followed, and overall survival (OS) and progression-free survival (PFS) were determined. The effects of different treatments on the hydrocephalus of patients were compared.

RESULTS

Postoperative hydrocephalus was identified as a factor to increase the risk of mortality by 1.99-fold (p = .028). And, 5-year survival rate was significantly lower among patients with postoperative hydrocephalus (p = .027). The main factors leading to preoperative hydrocephalus in patients are large tumor volume and invasion into the third ventricle. Gross total resections (GTR) could reduce the risk of long-term hydrocephalus (p = .046). Age younger than 4 years (p = .046) and tumor invasion range/classification (p = .029) are the main factors to reduce the five-year survival rate. Postoperative radiotherapy (RT) and chemotherapy (CT) had no significant effects on OS. Extraventricular drainage (EVD) was not associated with perioperative infection (p = .798 > .05) and bleeding (p = .09 > .05). Compared with 2 stage surgery (external ventricular drainage or ventriculoperitoneal shunt (VPS) was first placed, followed by tumor resection), 1 stage surgery (direct resection of tumor) had no complication increase.

CONCLUSIONS

Postoperative hydrocephalus is mostly obstructive hydrocephalus, and it is an important factor that reduces the OS of patients with low-grade OPGs. Surgery to remove the tumor to the greatest extent improves cerebrospinal fluid circulation is effective at reducing the incidence postoperative hydrocephalus. For patients whose ventricles are still dilated after surgery, in addition to considering poor ventricular compliance, they need to be aware of the persistence and progression of hydrocephalus.

Optic nerve sheath diameter correlates with both success and failure of hydrocephalus treatment in pediatric patients with pineal region lesions

BACKGROUND

Pineal region lesions in children are heterogenous pathologies often symptomatic due to occlusive hydrocephalus and thus elevated intracranial pressure (ICP). MRI-derived parameters to assess hydrocephalus are the optic nerve sheath diameter (ONSD) as a surrogate for ICP and the frontal occipital horn ratio (FOHR), representing ventricle volume. As elevated ICP may not always be associated with clinical signs, the adjunct of ONSD could help decision making in patients undergoing treatment. The goal of this study is to assess the available magnetic resonance imaging (MRI) of patients with pineal region lesions undergoing surgical treatment with respect to pre- and postoperative ONSD and FOHR as an indicator for hydrocephalus.

METHODS

Retrospective data analysis was performed in all patients operated for pineal region lesions at a tertiary care center between 2010 and 2023. Only patients with pre- and postoperative MRI were selected for inclusion. Clinical data and ONSD at multiple time points, as well as FOHR were analyzed. Imaging parameter changes were correlated with clinical signs of hydrocephalus before and after surgical treatment.

RESULTS

Thirty-three patients with forty operative cases met the inclusion criteria. Age at diagnosis was 10.9 ± 4.6 years (1-17 years). Hydrocephalus was seen in 80% of operative cases preoperatively (n = 32/40). Presence of hydrocephalus was associated with significantly elevated preoperative ONSD (p = 0.006). There was a significant decrease in ONSD immediately (p < 0.001) and at 3 months (p < 0.001) postoperatively. FOHR showed a slightly less pronounced decrease (immediately p = 0.006, 3 months p = 0.003). In patients without hydrocephalus, no significant changes in ONSD were observed (p = 0.369). In 6/6 patients with clinical hydrocephalus treatment failure, ONSD increased, but in 3/6 ONSD was the only discernible MRI change with unchanged FOHR.

CONCLUSIONS

ONSD measurements may have utility in evaluating intracranial hypertension due to hydrocephalus in patients with pineal region tumors. ONSD changes appear to have value in assessing hydrocephalus treatment failure.

Glymphatic Imaging in Pediatrics

The glymphatic system, which facilitates cerebrospinal fluid (CSF) flow through the brain parenchyma, is important for brain development and waste clearance. Advances in imaging techniques, particularly magnetic resonance imaging, have make it possible to evaluate glymphatic structures and functions in vivo. Recently, several studies have focused on the development and alterations of the glymphatic system in pediatric disorders. This review discusses the development of the glymphatic system, advances of imaging techniques and their applications in pediatric disorders. First, the results of the reviewed studies indicate that the development of the glymphatic system is a long-lasting process that continues into adulthood. Second, there is a need for improved glymphatic imaging techniques that are non-invasive and fast to improve suitability for pediatric applications, as some of existing methods use contrast injection and are susceptible to motion artifacts from long scanning times. Several novel techniques are potentially feasible for pediatric patients and may be used in the future. Third, the glymphatic dysfunction is associated with a large number of pediatric disorders, although only a few have recently been investigated. In conclusion, research on the pediatric glymphatic system remains an emerging field. The preliminary applications of glymphatic imaging techniques have provided unique insight into the pathological mechanism of pediatric diseases, but mainly limited in visualization of enlarged perivascular spaces and morphological measurements on CSF volumes. More in-depth studies on glymphatic functions are required to improve our understanding of the mechanisms underlying brain development and pediatric diseases. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 3.

Fast Quantitative Magnetic Resonance Imaging Evaluation of Hydrocephalus Using 3-Dimensional Fluid-Attenuated Inversion Recovery: Initial Experience

OBJECTIVE

This study aimed to demonstrate the initial experience of using fast quantitative magnetic resonance imaging (MRI) to evaluate hydrocephalus.

METHODS

A total of 109 brain MRI volumetry examinations (acquisition time, 7 minutes 30 seconds) were performed in 72 patients with hydrocephalus. From the measured ventricular system and brain volumes, ventricle-brain volume percentage was calculated to standardize hydrocephalus severity (processing time, <5 minutes). The obtained values were categorized into no, mild, and severe based on the fronto-occipital horn ratio (FOHR) and the ventricle-brain volume percentages reported in the literature. The measured volumes and percentages were compared between patients with mild hydrocephalus and those with severe hydrocephalus. The diagnostic performance of brain hydrocephalus MRI volumetry was evaluated using receiver operating characteristic curve analysis.

RESULTS

Ventricular volumes and ventricle-brain volume percentages were significantly higher in in patients with severe hydrocephalus than in those with mild hydrocephalus (FOHR-based severity: 352.6 ± 165.6 cm 3 vs 149.1 ± 78.5 cm 3 , P < 0.001, and 26.8% [20.8%-33.1%] vs 12.1% ± 6.0%, P < 0.001; percentage-based severity: 359.5 ± 143.3 cm 3 vs 137.0 ± 62.9 cm 3 , P < 0.001, and 26.8% [21.8%-33.1%] vs 11.3% ± 4.2%, P < 0.001, respectively), whereas brain volumes were significantly lower in patients with severe hydrocephalus than in those with mild hydrocephalus (FOHR-based severity: 878.1 ± 363.5 cm 3 vs 1130.1 cm 3 [912.1-1244.2 cm 3 ], P = 0.006; percentage-based severity: 896.2 ± 324.6 cm 3 vs 1142.3 cm 3 [944.2-1246.6 cm 3 ], P = 0.005, respectively). The ventricle-brain volume percentage was a good diagnostic parameter for evaluating the degree of hydrocephalus (area under the curve, 0.855; 95% confidence interval, 0.719-0.990; P < 0.001).

CONCLUSIONS

Brain MRI volumetry can be used to evaluate hydrocephalus severity and may provide guide interpretation because of its rapid acquisition and postprocessing times.

Normal values of the fronto-occipital relationship in fetuses between 18 and 40 weeks at two maternal fetal medicine units: Bogotá, Colombia

OBJECTIVE

To establish nomograms for linear measurements of the frontal and occipital horns of the lateral ventricle and their relationship, in pregnant patients between 18 and 40 weeks of gestation and having attended 2 units of Maternal Fetal Medicine in Bogotá-Colombia.

METHODOLOGY

A descriptive cross-sectional study with an analytical component was carried out on pregnant patients who utilized the ultrasound services at 2 Maternal-Fetal Medicine units in Bogotá, between 18 and 40 weeks of pregnancy who underwent measurement. From the anterior and posterior horns of the lateral ventricles, the fronto-occipital ratio was calculated at each gestational week, and nomograms were created for each of these variables.

RESULTS

Nine hundred and seventy-eight patients were included in the study. The distance of the frontal horns ranged between 6.9 and 51.6 mm with a mean of 19.1 ± 5.8 mm; that of the occipital horns had a measurement between 8.7 and 53 mm with a mean of 28, 1 ± 8.9 mm; on the other hand, the fronto-occipital ratio (FOR) yielded a mean of 0.365 ± 0.067 (0.136-0.616) without bearing any relation to gestational age. The trend of normal values for the studied population is displayed, plotted in percentile curves and nomograms for each gestational age.

CONCLUSION

The measurement of the frontal and occipital horns, and the calculation of the fronto-occipital relationship is technically possible between 18 and 40 weeks, finding that the anterior and posterior horns have a positive linear relationship with gestational age. Contrarily, the FOR does not correlate with the gestational age, it was possible to establish a table of percentiles that allows determining the normal values for these measurements during pregnancy.

Post-traumatic hydrocephalus: An overview of classification, diagnosis, treatment, and post-treatment imaging evaluation

The syndrome of post-traumatic hydrocephalus (PTH) has been recognized since Dandy's report in 1914. The pathogenesis of PTH has not been fully clarified. At present, it is believed that the obstacles of cerebrospinal fluid (CSF) secretion, absorption and circulation pathways are the reasons for the development of PTH. However, recent studies have also suggested that the osmotic pressure load of CSF and the pathological changes of CSF dynamics are caused by the development of hydrocephalus. Therefore, a better understanding of the definition, classification, diagnostic criteria, treatment, and evaluation of post-treatment effects of PTH is critical for the effective prevention and treatment of PTH. In this paper, we reviewed the classification and diagnosis of PTH and focused on the treatment and the imaging evaluation of post-treatment effects of PTH. This review might provide a judgment criterion for diagnosis of PTH and a basis for the effective prevention and treatment of PTH in the future.

Predictors of Neurodevelopment in Microcephaly Associated with Congenital Zika Syndrome: A Prospective Study

The municipality of Salvador, situated in Brazil, distinguished itself as the epicenter of the emergence of microcephaly related to congenital manifestations of Zika syndrome. Despite the anticipated significant developmental setbacks in these children, research has indicated a varied range of outcomes, with certain instances even reflecting minimal developmental delay. Our objective was to pinpoint determinants that could forecast developmental anomalies in children diagnosed with microcephaly associated with congenital Zika syndrome (CZS).

METHODOLOGY

A forward-looking clinical and neurodevelopmental examination was conducted focusing on neonates diagnosed with microcephaly with CZS, birthed between September 2015 and April 2016 at the Hospital Geral Roberto Santos, in Salvador city. That infants were monitored up to their third year by a multiprofessional team. Child development was assessed using the composite Bayley III score. Undertaken by two blinded experts, cranial CT scan analysis was performed during the neonate period for the detection of brain abnormalities and to quantify ventricle enlargement, measured by Evans' index (EI).

RESULTS

Fifty newborns were evaluated with a median head circumference of 28 cm (interquartile range 27-31 cm). EI was associated with neurodevelopmental delay at three years and remained significant after adjustment for head circumference. A 0.1-point increase in EI was associated with a delay of 3.2 months in the receptive language (p = 0.016), 3.4 months in the expressive language (p = 0.016), 3.4 months in the cognitive (p = 0.016), 2.37 months in the gross motor (p = 0.026), and 3.1 months in the fine motor (p = 0.021) domains.

CONCLUSIONS

EI predicted neurodevelopmental delay in all Bayley domains in children with microcephaly associated with CZS.

A comparison of ventricular volume and linear indices in predicting shunt dependence in aneurysmal subarachnoid hemorrhage

Background

Guidelines for determining shunt dependence after aneurysmal subarachnoid hemorrhage (aSAH) remain unclear. We previously demonstrated change in ventricular volume (VV) between head CT scans taken pre- and post-EVD clamping was predictive of shunt dependence in aSAH. We sought to compare the predictive value of this measure to more commonly used linear indices.

Methods

We retrospectively analyzed images of 68 patients treated for aSAH who required EVD placement and underwent one EVD weaning trial, 34 of whom underwent shunt placement. We utilized an in-house MATLAB program to analyze VV and supratentorial VV (sVV) in head CT scans obtained before and after EVD clamping. Evans' index (EI), frontal and occipital horn ratio (FOHR), Huckman's measurement, minimum lateral ventricular width (LV-Min.), and lateral ventricle body span (LV-Body) were measured using digital calipers in PACS. Receiver operating curves (ROC) were generated.

Results

Area under the ROC curves (AUC) for the change in VV, sVV, EI, FOHR, Huckman's, LV-Min., and LV-Body with clamping were 0.84, 0.84, 0.65, 0.71.0.69, 0.67, and 0.66, respectively. AUC for post-clamp scan measurements were 0.75, 0.75, 0.74, 0.72, 0.72, 0.70, and 0.75, respectively.

Conclusion

VV change with EVD clamping was more predictive of shunt dependence in aSAH than change in linear measurements with clamping and all post-clamp measurements. Measurement of ventricular size on serial imaging with volumetrics or linear indices utilizing multidimensional data points may therefore be a more robust metric than unidimensional linear indices in predicting shunt dependence in this cohort. Prospective studies are needed for validation.

Linear indices of ventricular volume on brain computed tomography as markers of effectiveness of epidural blood patch for spontaneous intracranial hypotension: A case report

RATIONALE

Epidural blood patch (EBP) is an effective treatment for spontaneous intracranial hypotension (SIH). However, its effectiveness can only be judged through subjective symptom improvement; no objective markers have been reported. Linear indices of ventricular volume on brain computed tomography (CT) may aid the objective evaluation of the effectiveness of EBP in patients with SIH.

PATIENT CONCERNS

A 45-year-old man was hospitalized due to a 3-week history of orthostatic headache, dizziness, and neck pain. He had visited a local emergency department at symptom onset. His neurological examination results were normal and vital signs were stable.

DIAGNOSES

Brain magnetic resonance imaging (MRI) revealed pachymeningeal enhancement in both convexities with a small subdural hematoma (SDH). Based on the clinical features and MRI findings, he was diagnosed with SIH complicated by SDH.

INTERVENTIONS

Non-targeted EBP was performed, first at the lumbar level and subsequently at the thoracic level. Linear indices of ventricular volume, including the Evans' index, frontal-occipital horn ratio, and bicaudate index, were measured through brain CT performed before and after EBP.

OUTCOMES

After lumbar EBP, there was no symptom relief or increase in linear indices of ventricular volume on brain CT. In contrast, the patient's symptoms completely resolved and the linear indices of ventricular volume increased after thoracic EBP.

LESSONS

The effectiveness of EBP, which is currently evaluated solely based on changes in symptom severity, can be assessed using linear indices of ventricular volume.

Ventriculomegaly in children: nocturnal ICP dynamics identify pressure-compensated but active paediatric hydrocephalus

INTRODUCTION

Paediatric ventriculomegaly without obvious signs or symptoms of raised intracranial pressure (ICP) is often interpreted as resulting from either relative brain atrophy, arrested "benign" hydrocephalus, or "successful" endoscopic third ventriculostomy (ETV). We hypothesise that the typical ICP "signature" found in symptomatic hydrocephalus can be present in asymptomatic or oligosymptomatic children, indicating pressure-compensated, but active hydrocephalus.

METHODS

A total of 37 children fulfilling the mentioned criteria underwent computerised ICP overnight monitoring (ONM). Fifteen children had previous hydrocephalus treatment. ICP was analysed for nocturnal dynamics of ICP, ICP amplitudes (AMP), magnitude of slow waves (SLOW), and ICP/AMP correlation index RAP. Depending on the ONM results, children were either treated or observed. The ventricular width was determined at the time of ONM and at 1-year follow-up.

RESULTS

The recordings of 14 children (group A) were considered normal. In the 23 children with pathologic recordings (group B), all ICP values and dependent variables (AMP, SLOW) were significantly higher, except for RAP. In group B, 12 of 15 children had received a pre-treatment and 11 of 22 without previous treatment. All group B children received treatment for hydrocephalus and showed a significant reduction of frontal-occipital horn ratio at 1 year. During follow-up, a positive neurological development was seen in 74% of children of group A and 100% of group B.

CONCLUSION

Ventriculomegaly in the absence of signs and symptoms of raised ICP was associated in 62% of cases to pathological ICP dynamics. In 80% of pre-treated cases, ETV or shunt failure was found. Treating children with abnormal ICP dynamics resulted in an outcome at least as favourable as in the group with normal ICP dynamics. Thus, asymptomatic ventriculomegaly in children deserves further investigation and, if associated with abnormal ICP dynamics, should be treated in order to provide a normalised intracranial physiology as basis for best possible long-term outcome.

Automated Lateral Ventricular and Cranial Vault Volume Measurements in 13,851 Patients Using Deep Learning Algorithms

BACKGROUND

No large dataset-derived standard has been established for normal or pathologic human cerebral ventricular and cranial vault volumes. Automated volumetric measurements could be used to assist in diagnosis and follow-up of hydrocephalus or craniofacial syndromes. In this work, we use deep learning algorithms to measure ventricular and cranial vault volumes in a large dataset of head computed tomography (CT) scans.

METHODS

A cross-sectional dataset comprising 13,851 CT scans was used to deploy U-Net deep learning networks to segment and quantify lateral cerebral ventricular and cranial vault volumes in relation to age and sex. The models were validated against manual segmentations. Corresponding radiologic reports were annotated using a rule-based natural language processing framework to identify normal scans, cerebral atrophy, or hydrocephalus.

RESULTS

U-Net models had high fidelity to manual segmentations for lateral ventricular and cranial vault volume measurements (Dice index, 0.878 and 0.983, respectively). The natural language processing identified 6239 (44.7%) normal radiologic reports, 1827 (13.1%) with cerebral atrophy, and 1185 (8.5%) with hydrocephalus. Age-based and sex-based reference tables with medians, 25th and 75th percentiles for scans classified as normal, atrophy, and hydrocephalus were constructed. The median lateral ventricular volume in normal scans was significantly smaller compared with hydrocephalus (15.7 vs. 82.0 mL; P < 0.001).

CONCLUSIONS

This is the first study to measure lateral ventricular and cranial vault volumes in a large dataset, made possible with artificial intelligence. We provide a robust method to establish normal values for these volumes and a tool to report these on CT scans when evaluating for hydrocephalus.

Risk Factors of Persistent Hydrocephalus in Children with Brain Tumor: A Retrospective Analysis

OBJECT

Hydrocephalus is one of the main complications of brain tumors in children, being present in about 50% of cases at the time of the tumor diagnosis and persisting up to 10-40% of cases after surgical resection. This is a single-institution retrospective study on the variables that may predict the need for treatment of persistent hydrocephalus in pediatric patients presenting with a brain tumor.

METHODS

Retrospective case note review of 43 newly diagnosed brain tumors in children referred between April 2012 and January 2018 to our regional pediatric neuro-oncology service was carried out. Diagnosis of hydrocephalus was carried out using both preoperative and postoperative MRI to determine Evans' index (EI) and the fronto-occipital horn ratio (FOHR) from each scan. Simple logistic regression was used to analyze categorical variables as appropriate. A p value <0.05 was considered significant.

RESULTS

Forty-three children were analyzed, 26 males and 17 females with a median age at diagnosis 10.4 years (IQR: 5.2-13.5). Hydrocephalus was present in 22/43 children (51%) preoperatively; in 8/22 children (36%) with hydrocephalus undergoing tumor resection, hydrocephalus persisted also in the postoperative period. An EI >0.34 (p = 0.028) and an FOHR >0.46 (p = 0.05) before surgery were associated with a higher prevalence of persistent hydrocephalus and therefore to the need for a cerebrospinal fluid drain device in the postoperative phase.

CONCLUSION

Preoperative identification of children at risk for developing persistent hydrocephalus would avoid delays in planning the permanent cerebrospinal fluid drain devices. This study finds that an EI >0.34 and an FOHR >0.46 at diagnosis could impact on the therapeutic management of children with hydrocephalus associated with brain tumors. Prospective and larger-scale studies are needed to standardize this approach.

A preliminary exploration of acute intracranial pressure-cerebrospinal fluid production relationships in experimental hydrocephalus

CONTEXT

By occluding the fourth ventricle simultaneously obtaining telemetric data on intracranial pressure (ICP) and cerebrospinal fluid (CSF) production, the authors of this study investigate a variety of physiologic parameters in cases of experimental hydrocephalus.

AIMS

The aim of this study is to provide a new context on the disrupted homeostasis in hydrocephalus and guide toward improved treatment based on multiple physiological parameters.

MATERIALS AND METHODS

Hydrocephalus was induced in ten 21-day-old Sprague-Dawley rats by blocking the flow of CSF to the fourth ventricle with kaolin. Ten days post induction, when physical signs of ventriculomegaly reached Evan's ratio (ER) of ≥0.46, CSF flow and ICP were measured while manipulating body position (0°, 45°, 90°) and heart rate.

RESULTS

In hydrocephalic animals (ER ≥0.46), we found a near-steady average acute ICP (13.638 ± 2.331) compared to age-matched controls (ER <0.30) (13.068 ± 8.781), whose ICP fluctuated with the position. Hydrocephalic and controls exhibited an insignificant degree of parabolic shifts in CSF production when body position was changed from prone to 90° and again when moved back to the prone position, a trend more noteworthy in controls (P = 0.1322 and 0.2772). A Pearson's Correlation found CSF production and ICP to be correlated at baseline 0° posture (P = 0.05) in the control group, but not the hydrocephalic group. Weight appeared to play a role when animals were held at 90°. No significant changes in ICP or CSF flow patterns were observed when the heart rate was increased within either group.

CONCLUSIONS

These preliminary findings suggest that our standard assumptions of posture-dependent changes in ICP created using data from physiologic data may be inaccurate in the hydrocephalic patient, and thus describe a need to further explore these relationships.

Normal cerebral ventricular volume growth in childhood

OBJECTIVE

Normal percentile growth charts for head circumference, length, and weight are well-established tools for clinicians to detect abnormal growth patterns. Currently, no standard exists for evaluating normal size or growth of cerebral ventricular volume. The current standard practice relies on clinical experience for a subjective assessment of cerebral ventricular size to determine whether a patient is outside the normal volume range. An improved definition of normal ventricular volumes would facilitate a more data-driven diagnostic process. The authors sought to develop a growth curve of cerebral ventricular volumes using a large number of normal pediatric brain MR images.

METHODS

The authors performed a retrospective analysis of patients aged 0 to 18 years, who were evaluated at their institution between 2009 and 2016 with brain MRI performed for headaches, convulsions, or head injury. Patients were excluded for diagnoses of hydrocephalus, congenital brain malformations, intracranial hemorrhage, meningitis, or intracranial mass lesions established at any time during a 3- to 10-year follow-up. The volume of the cerebral ventricles for each T2-weighted MRI sequence was calculated with a custom semiautomated segmentation program written in MATLAB. Normal percentile curves were calculated using the lambda-mu-sigma smoothing method.

RESULTS

Ventricular volume was calculated for 687 normal brain MR images obtained in 617 different patients. A chart with standardized growth curves was developed from this set of normal ventricular volumes representing the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles. The charted data were binned by age at scan date by 3-month intervals for ages 0-1 year, 6-month intervals for ages 1-3 years, and 12-month intervals for ages 3-18 years. Additional percentile values were calculated for boys only and girls only.

CONCLUSIONS

The authors developed centile estimation growth charts of normal 3D ventricular volumes measured on brain MRI for pediatric patients. These charts may serve as a quantitative clinical reference to help discern normal variance from pathologic ventriculomegaly.

Hydrocephalus: Ventricular Volume Quantification Using Three-Dimensional Brain CT Data and Semiautomatic Three-Dimensional Threshold-Based Segmentation Approach

OBJECTIVE

To evaluate the usefulness of the ventricular volume percentage quantified using three-dimensional (3D) brain computed tomography (CT) data for interpreting serial changes in hydrocephalus.

MATERIALS AND METHODS

Intracranial and ventricular volumes were quantified using the semiautomatic 3D threshold-based segmentation approach for 113 brain CT examinations (age at brain CT examination ≤ 18 years) in 38 patients with hydrocephalus. Changes in ventricular volume percentage were calculated using 75 serial brain CT pairs (time interval 173.6 ± 234.9 days) and compared with the conventional assessment of changes in hydrocephalus (increased, unchanged, or decreased). A cut-off value for the diagnosis of no change in hydrocephalus was calculated using receiver operating characteristic curve analysis. The reproducibility of the volumetric measurements was assessed using the intraclass correlation coefficient on a subset of 20 brain CT examinations.

RESULTS

Mean intracranial volume, ventricular volume, and ventricular volume percentage were 1284.6 ± 297.1 cm³, 249.0 ± 150.8 cm³, and 19.9 ± 12.8%, respectively. The volumetric measurements were highly reproducible (intraclass correlation coefficient = 1.0). Serial changes (0.8 ± 0.6%) in ventricular volume percentage in the unchanged group (n = 28) were significantly smaller than those in the increased and decreased groups (6.8 ± 4.3% and 5.6 ± 4.2%, respectively; p = 0.001 and p < 0.001, respectively; n = 11 and n = 36, respectively). The ventricular volume percentage was an excellent parameter for evaluating the degree of hydrocephalus (area under the receiver operating characteristic curve = 0.975; 95% confidence interval, 0.948-1.000; p < 0.001). With a cut-off value of 2.4%, the diagnosis of unchanged hydrocephalus could be made with 83.0% sensitivity and 100.0% specificity.

CONCLUSION

The ventricular volume percentage quantified using 3D brain CT data is useful for interpreting serial changes in hydrocephalus.

Suprasellar arachnoid cysts in adults: clinical presentations, radiological features, and treatment outcomes

A tendency for suprasellar arachnoid cysts (SACs) to occur in young children is known. Data of adult SACs were rare in previous reports. The aim of this study is to discuss their clinical presentations, radiological features, and treatment outcomes based on 23 adult patients who underwent endoscopic fenestration in our hospital between January 2003 and December 2018. Preoperative cyst volume ranged from 12.3 to 72.5 cm³ (mean 39.8 ± 19.8). Endocrine disorders occurred in 7 (30.4%) patients. Hydrocephalus was observed in 20 patients. In the patients with hydrocephalus, the mean preoperative Evans' index (EI) (%) and frontooccipital horn ratio (FOHR) (%) were 44.8 (ranged 32.2-63.4) and 49.6 (ranged 36.7-59.8), respectively. A bivariate correlation showed significant positive association between preoperative cyst volume and preoperative EI or FOHR (Pearson correlation, r = 0.607, p = 0.005; r = 0.583, p = 0.007). The slit-valve phenomenon was observed in 13 (56.5%) patients. Pale/tenacious cyst walls were observed in 12 (52.2%) patients. Postoperatively, all patients achieved the improvement in clinical symptoms and a decrease in cyst size. The mean decreases in cyst volume, EI, and FOHR were 64.7%, 7.89%, and 5.8%, respectively. A bivariate correlation indicated the irrelevance between the postoperative cyst volume and postoperative EI or FOHR (Pearson correlation: r = 0.37, p = 0.11; r = 0.43, p = 0.054). These results reveal that there are a few differences in several aspects between adult patients and child patients. The severity of hydrocephalus is correlated with cyst size in adult patients. Additionally, the excellent outcomes in adult SACs can be obtained by endoscopic fenestration.

Planar single plane area determination is a viable substitute for total volumetry of CSF and brain in childhood hydrocephalus

BACKGROUND

In the treatment of childhood hydrocephalus, 3D volumetry seems to have many advantages over classical planar index measurements for dedicated monitoring of changes in cerebrospinal fluid and brain volume. Nevertheless, this method requires extensive technical effort and access to the complete three-dimensional data set. Against this background, we evaluated the possibility of planar area determination in a single plane and the correlation to volumetry.

METHODS

138 routinely performed true FISP MRI sequences (1 mm isovoxel) were analyzed retrospectively in 68 patients with pediatric hydrocephalus. After preprocessing, the 3D-data sets were skull stripped to estimate the inner skull volume. A 2-class segmentation into different tissue types (brain matter and CSF) was performed, and the volumes of CSF (VCSF) and brain matter (VBrain) were calculated. A plane at the level of the foramina of Monro was manually identified in the ac-pc oriented data. In this plane, the areas of brain (ABrain) and CSF (ACSF) in cm² were calculated and used for further correlation analysis.

RESULTS

Mean VCSF was 340 ± 145 cm³ and VBrain 1173 ± 254 cm³. In the selected plane, ACSF was 26 ± 14 cm², and ABrain was 107 ± 25 cm². There was a very strong positive correlation between both ACSF and VCSF (r = 0.895) and between ABrain and VBrain (r = 0.846). The prediction equations for VBrain and VCSF were highly significant.

CONCLUSION

Planar area determination of brain and CSF correlates excellently with both VCSF and VBrain. Thus, areas can serve as a surrogate marker for total brain and CSF volumes for a quantitated objective tracking of changes during treatment of childhood hydrocephalus.

Automatic volumetry of cerebrospinal fluid and brain volume in severe paediatric hydrocephalus, implementation and clinical course after intervention

BACKGROUND

In childhood hydrocephalus, both the amount of cerebrospinal fluid and the brain volume are relevant for the prognosis of the development and for therapy monitoring. Since classical planar measurements of ventricular size are subject to strong limitations, imprecise and neglect brain volume, 3D volumetry is most desirable. We used and evaluated the robust segmentation algorithms of the freely available FSL-toolbox in paediatric hydrocephalus patients before and after specific therapy.

METHODS

Retrospectively 76 pre- and postoperative high-resolution T2-weighted MRI sequences (true FISP, 1 mm isovoxel) were analyzed in 38 patients with paediatric hydrocephalus (mean 4.4 ± 5.1 years) who underwent surgical treatment (ventriculo-peritoneal (VP) shunt n = 22, endoscopic third ventriculostomy (ETV) n = 16). After preprocessing, the 3D-datasets were skull stripped to estimate the inner skull surface. Following, a 2 class segmentation into different tissue types (brain matter and CSF) was performed. The volumes of CSF and brain were calculated.

RESULTS

The method could be implemented in an automated fashion in all 76 MRIs. In the VP shunt cohort, the amount of CSF (p < 0.001) decreased. Consecutively brain volume increased significantly (p < 0.001). Following ETV, CSF volume (p = 0.019) decreased significantly (p = 0.012) although the reduction was less pronounced than after shunt implantation. Brain volume expanded (p = 0.02).

CONCLUSION

A reliable automated segmentation of CSF and brain could be performed with the implemented algorithm. The method was able to track changes after therapy and detected significant differences in CSF and brain volumes after shunting and after ETV.

Changes of third ventricle diameter (TVD) mirror changes of the entire ventricular system after initial therapy and during follow-up in pediatric hydrocephalus

PURPOSE

Regular measurement of ventricular size is important in children with hydrocephalus. After closure of the fontanelle this is currently addressed by repetitive cranial MRI or CT imaging, coming along with risks of anaesthesia or radiation. As the third ventricle is accessible via the temporal bone window using ultrasound, determination of its diameter might be an easy and radiation-free alternative to assess the ventricular system. An essential precondition is that changes of the third ventricle diameter (TVD) mirror changes of the whole ventricular system. This study compares changes of TVD with changes of ventricular indices before and after initial treatment of hydrocephalus and during the following evolution.

METHODS

MRT/CT images from 117 children with hydrocephalus were evaluated at time of diagnosis, after initial therapy and during follow-up with functional shunts. Measurements included axial TVD and three standard linear measures of the lateral ventricles (Evans Index - EI, fronto-occipital horn ratio - FOHR Index, and Cella Media Index - CMI). Furthermore, a correlation within subjects was calculated in 8 patients over the entire available follow-up.

RESULTS

Relative changes of TVD were significantly correlated to relative changes of all ventricular indices (r = 0.48, r = 0.68 and r = 0.701 for EI, FOHR and CMI, respectively, p < 0.01). The correlation within subjects was outstanding for EI (r = 0.988), FOHR (r = 0.99) and CMI (r = 0.99).

CONCLUSION

TVD showed a significant correlation with all three linear indices at the time of diagnosis and during follow-up changes independently of age, aetiology and ventricular width. TVD and its changes are therefore a reliable surrogate of changes in ventricular size in pediatric hydrocephalus undergoing treatment.

Measurement of lateral ventricle volume of normal infant based on magnetic resonance imaging

Background

Many neurophysiological diseases during infancy stage are associated with the morphology and size of the lateral ventricle. This research aims to measure the normal value range of lateral ventricle volume of normal infant and thus provide basic data for clinical treatment.

Method

By retrospective analysis of magnetic resonance inspection (MRI) cranial image of 165 infants in the Department of Pediatric Neurosurgery, Beijing Tiantan Hospital, the infants were divided into four groups according to their age, including the first group (1~3 month, n = 12), the second group (4~6 month, n = 33), the third group (7~9 month, n = 51), and the fourth group (10~12 month, n = 69). On Neurosoft image workstation, it can measure the sectional area of the lateral ventricle volume at each layer of axis T2W image and calculate the lateral ventricle volume using the Cavalieri method. Moreover, the correlations between lateral ventricle volume and gender, side difference, and month age were analyzed.

Results

95% confidence interval of total bilateral ventricle volume of normal infant: 11920.22~14,266.28 mm³ for male infant and 9922.22~12,263.17 mm³ for female infant; 95% confidence interval of left side ventricle volume: 6254.72~7546.94 mm³ for male infant and 5206.03~6479.99 mm³ for female infant; 95% confidence interval of right side ventricle volume: 5041.56~6743.29 mm³ for male infant and 4695.00~5804.40 mm³ for female infant. The lateral ventricle volume of the male infant was normally larger than that of the female infant (p < 0.05). For both male and female infants, the left side ventricle volume was larger than the right ventricle volume (p < 0.01). There was no significant difference in lateral ventricle volume between infants over 3 months old.

Conclusion

The normal value range of lateral ventricle volume of the infant can be obtained via referring MRI image. The lateral ventricle volume of infant varies upon gender and ventricle side.

Impaired hippocampal development and outcomes in very preterm infants with perinatal brain injury

Preterm infants are at high risk for brain injury during the perinatal period. Intraventricular hemorrhage and periventricular leukomalacia, the two most common patterns of brain injury in prematurely-born children, are associated with poor neurodevelopmental outcomes. The hippocampus is known to be critical for learning and memory; however, it remains unknown how these forms of brain injury affect hippocampal growth and how the resulting alterations in hippocampal development relate to childhood outcomes. To investigate these relationships, hippocampal segmentations were performed on term equivalent MRI scans from 55 full-term infants, 85 very preterm infants (born ≤32 weeks gestation) with no to mild brain injury and 73 very preterm infants with brain injury (e.g., grade III/IV intraventricular hemorrhage, post-hemorrhagic hydrocephalus, cystic periventricular leukomalacia). Infants then underwent standardized neurodevelopmental testing using the Bayley Scales of Infant and Toddler Development, 3rd edition at age 2 years, corrected for prematurity. To delineate the effects of brain injury on early hippocampal development, hippocampal volumes were compared across groups and associations between neonatal volumes and neurodevelopmental outcomes at age 2 years were explored. Very preterm infants with brain injury had smaller hippocampal volumes at term equivalent age compared to term and very preterm infants with no to mild injury, with the smallest hippocampi among those with grade III/IV intraventricular hemorrhage and post-hemorrhagic hydrocephalus. Further, larger ventricle size was associated with smaller hippocampal size. Smaller hippocampal volumes were related to worse motor performance at age 2 years across all groups. In addition, smaller hippocampal volumes in infants with brain injury were correlated with impaired cognitive scores at age 2 years, a relationship specific to this group. Consistent with our preclinical findings, these findings demonstrate that perinatal brain injury is associated with hippocampal size in preterm infants, with smaller volumes related to domain-specific neurodevelopmental impairments in this high-risk clinical population.

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Perinatal brain injury is related to smaller hippocampal volumes in preterm infants

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Infants with high-grade intraventricular hemorrhage have smallest hippocampi

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Larger ventricular size is related to smaller hippocampal volumes in hydrocephalus

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Smaller hippocampi are related to worse cognitive outcomes in brain injured infants

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Smaller hippocampal volumes associated with worse motor performance across groups

The Importance of Measuring Mamillopontine Distance as a Diagnostic Criterion of Hydrocephalus Degrees

OBJECTIVES

The occurrence of obstructive hydrocephalus (ObH) as sequelae of deep midline brain tumors (third and lateral ventricles, thalamic, pineal region, brainstem, and fourth ventricle) can be estimated up to 90% of cases. We believe that the mamillopontine distance (MPD) - the distance between the lower surface of the mammillary body and the upper surface of the pons in the sagittal images - can be a sufficiently reliable alternative to the Evans' index (EI) for the diagnosis of ObH.

PATIENTS AND METHODS

The results of mamillopontine distance (MPD), Evans' index (EI), and angle of corpus callosum (ACC) measurement of 43 patients with non-communicative hydrocephalus were analyzed compared with results of 30 people without brain pathology.

RESULTS

Findings revealed that MPD is a strong and reliable alternative to the EI. MPD showed high specificity and sensitivity in the diagnosis of occlusive hydrocephalus. Moreover, from those findings, we have proposed classification of the degree of hydrocephalus severity, depending on the MPD.

CONCLUSION

MPD one of the more accurate and powerful method for defining presence of hydrocephalus in-patient even in early stage of occlusion. It has high specificity and sensitivity and capable classify hydrocephalus into grades according to severity.

Overdrainage-related ependymal bands: a postulated cause of proximal shunt obstruction

OBJECTIVEVentricular shunts have an unacceptably high failure rate, which approaches 50% of patients at 2 years. Most shunt failures are related to ventricular catheter obstruction. The literature suggests that obstructions are caused by in-growth of choroid plexus and/or reactive cellular aggregation. The authors report endoscopic evidence of overdrainage-related ventricular tissue protrusions ("ependymal bands") that cause partial or complete obstruction of the ventricular catheter.METHODSA retrospective review was completed on patients undergoing shunt revision surgery between 2008 and 2015, identifying all cases in which the senior author reported endoscopic evidence of ependymal tissue in-growth into ventricular catheters. Detailed clinical, radiological, and surgical findings are described.RESULTSFifty patients underwent 83 endoscopic shunt revision procedures that revealed in-growth of ventricular wall tissue into the catheter tip orifices (ependymal bands), producing partial, complete, or intermittent shunt obstructions. Endoscopic ventricular explorations revealed ependymal bands at various stages of development, which appear to form secondarily to siphoning. Ependymal bands are associated with small ventricles when the shunt is functional, but may dilate at the time of obstruction.CONCLUSIONSVentricular wall protrusions are a significant cause of proximal shunt obstruction, and they appear to be caused by siphoning of surrounding tissue into the ventricular catheter orifices.

Time-to-event analysis of surgically treated posthemorrhagic hydrocephalus in preterm infants: a single-institution retrospective study

PURPOSE

The purpose of this study is to report time points relevant to the neurosurgical management of posthemorrhagic hydrocephalus (PHH).

METHODS

Data were collected retrospectively on 104 preterm infants with intraventricular hemorrhage (IVH) who received neurosurgical intervention for PHH at St. Louis Children's Hospital from 1994 to 2016. Kaplan-Meier curves were constructed for various endpoints.

RESULTS

IVH grade on head ultrasound obtained through routine clinical care was II, III, and IV in 5 (4.8%), 33 (31.7%), and 66 (63.5%) of the patients, respectively. Neither IVH size nor location appeared to affect development of PHH. Days from birth to IVH, ventriculomegaly, temporizing neurosurgical procedure (TNP), and permanent neurosurgical intervention were 2.0 (95% CI 1.7-2.3), 3.0 (2.5-3.5), 24.0 (22.2-25.8), and 101.0 (90.4-111.6), respectively. Grades III and IV IVH did not differ in age at IVH diagnosis (Χ ² (1 d.f.) = 1.32, p = 0.25), ventriculomegaly (Χ ² = 0.73, p = 0.40), TNP (Χ ² = 0.61, p = 0.43), or permanent intervention (Χ ² = 2.48, p = 0.17). Ventricular reservoirs and ventriculosubgaleal shunts were used in 71 (68.3%) and 30 (28.8%), respectively. Eighty (76.9%) of the patients ultimately received a VPS. Five (4.8%) underwent a primary endoscopic third ventriculostomy (ETV), and two (1.9%) had ETV for a revision procedure. Four of the seven ETVs had choroid plexus cauterization.

CONCLUSIONS

Although most infants who develop IVH and ventriculomegaly will do so within a few days of birth, at-risk infants should be observed for at least 4 weeks with serial head ultrasounds to monitor for PHH requiring surgery.

Quantitative Synthetic MRI in Children: Normative Intracranial Tissue Segmentation Values during Development

BACKGROUND AND PURPOSE

Synthetic MR imaging is a new technique to create absolute R1 relaxivity (1/T1), R2 relaxivity (1/T2), and proton-density maps using a single multiple-spin-echo saturation recovery sequence. These relaxivity maps allow rapid automated intracranial segmentation of tissue types. To assess its utility in children, we created a normative data base of intracranial volume and brain parenchymal, GM, WM, CSF, and myelin volumes in a pediatric population with normal brain MRI findings using synthetic MR imaging.

MATERIALS AND METHODS

All multiple-spin-echo saturation recovery sequences containing brain MR imaging examinations performed during 34 months were retrospectively reviewed. Abnormal examination findings were excluded following a detailed radiographic and clinical chart review. The remaining normal examination findings were then quantitatively analyzed with synthetic MR imaging. Intracranial, brain parenchymal, GM, WM, CSF, and myelin volumes were plotted versus age. Qualitative assessment of segmentation accuracy was performed. Selected abnormal examination findings were compared with these normative curves.

RESULTS

One hundred twenty-two MRI examinations with normal findings were included of individuals ranging from 0.1 to 21.5 years of age (median, 11.8 years). Resulting normative data plots compared favorably with previously published data obtained using more onerous techniques. Differentiation from pathologic states was possible using quantitative values in select cases.

CONCLUSIONS

A pediatric data base of normal intracranial tissue volumes using a single sequence and rapid software analysis has been compiled and correlates with previously published data. This provides a framework for clinical interpretation of quantitative synthetic MR images during development. Improved age-based segmentation algorithms in young children are needed.

Environmental enrichment reduces brain damage in hydrocephalic immature rats

PURPOSE

We investigate the effects of environmental enrichment (EE) on morphological alterations in different brain structures of pup rats submitted to hydrocephalus condition.

METHODS

Hydrocephalus was induced in 7-day-old pup rats by injection of 20% kaolin into the cisterna magna. Ventricular dilatation and magnetization transfer to analyze myelin were assessed by magnetic resonance. Hydrocephalic and control rats exposed to EE (n = 10 per group) were housed in cages with a tunnel, ramp, and colored plastic balls that would emit sound when touched. The walls of the housing were decorated with colored adhesive tape. Moreover, tactile and auditory stimulation was performed daily throughout the experiment. Hydrocephalic and control rats not exposed to EE (n = 10 per group) were allocated singly in standard cages. All animals were weighed daily and exposed to open-field conditions every 2 days until the end of the experiment when they were sacrificed and the brains removed for histology and immunohistochemistry. Solochrome cyanine staining was performed to assess the thickness of the corpus callosum. The glial fibrillary acidic protein method was used to evaluate reactive astrocytes, and the Ki67 method to assess cellular proliferation in the subventricular zone.

RESULTS

The hydrocephalic animals exposed to EE showed better performance in Open Field tests (p < 0.05), while presenting lower weight gain. In addition, these animals showed better myelination as revealed by magnetization transfer (p < 0.05). Finally, the EE group showed a reduction in reactive astrocytes by means of glial fibrillary acidic protein immunostaining and preservation of the proliferation potential of progenitor cells.

CONCLUSION

The results suggest that EE can protect the developing brain against damaging effects caused by hydrocephalus.

Correlations of atrial diameter and frontooccipital horn ratio with ventricle size in fetal ventriculomegaly

OBJECTIVE Fetal ventriculomegaly (FV), or enlarged cerebral ventricles in utero, is defined in fetal studies as an atrial diameter (AD) greater than 10 mm. In postnatal studies, the frontooccipital horn ratio (FOHR) is commonly used as a proxy for ventricle size (VS); however, its role in FV has not been assessed. Using image analysis techniques to quantify VS on fetal MR images, authors of the present study examined correlations between linear measures (AD and FOHR) and VS in patients with FV. METHODS The authors performed a cross-sectional study using fetal MR images to measure AD in the axial plane at the level of the atria of the lateral ventricles and to calculate FOHR as the average of the frontal and occipital horn diameters divided by the biparietal distance. Computer software was used to separately segment and measure the area of the ventricle and the ventricle plus the subarachnoid space in 2 dimensions. Segmentation was performed on axial slices 3 above and 3 below the slice used to measure AD, and measurements for each slice were combined to yield a volume, or 3D VS. The VS was expressed as the absolute number of voxels (non-normalized) and as the number of voxels divided by intracranial size (normalized). A Pearson correlation coefficient was used to measure the strength of the relationships between the linear measures and the size of segmented regions in 2 and 3 dimensions and over various gestational ages (GAs). Differences between correlations were compared using Steiger's z-test. RESULTS Fifty FV patients who had undergone fetal MRI between 2008 and 2014 were included in the study. The mean GA was 26.3 ± 5.4 weeks. The mean AD was 18.1 ± 8.3 mm, and the mean FOHR was 0.49 ± 0.11. When using absolute VS, the correlation between AD and 3D VS (r = 0.844, p < 0.0001) was significantly higher than that between FOHR and 3D VS (r = 0.668, p < 0.0001; p = 0.0004, Steiger's z-test). However, when VS was normalized, correlations were not significantly different between AD and 3D VS (r = 0.830, p < 0.0001) or FOHR and 3D VS (r = 0.842, p < 0.0001; p = 0.8, Steiger's z-test). For GAs of 24 weeks or earlier, AD correlated more strongly with normalized 3D VS (r = 0.902, p < 0.0001) than with FOHR (r = 0.674, p < 0.0001; p < 0.0001, Steiger's z-test). After 24 weeks, there was no difference in correlations between linear measures (AD or FOHR) and 3D VS (r > 0.9). Correlations of linear measures with VS in 2 and 3 dimensions were similar, and inclusion of the subarachnoid space did not significantly alter results. CONCLUSIONS Findings in the study support the use of AD as a measure of VS in fetal studies as it correlates highly with both absolute and relative VS, especially at early GAs, and captures the preferential dilation of the occipital horns in patients with FV. Compared with AD, FOHR similarly correlates with normalized VS and, after a GA of 24 weeks, can be reported in fetal studies to provide continuity with postnatal monitoring.

Determinants of Indices of Cerebral Volume in Former Very Premature Infants at Term Equivalent Age

Conventional magnetic resonance imaging (MRI) at term equivalent age (TEA) is suggested to be a reliable tool to predict the outcome of very premature infants. The objective of this study was to determine simple reproducible MRI indices, in premature infants and to analyze their neonatal determinants at TEA. A cohort of infants born before 32 weeks gestational age (GA) underwent a MRI at TEA in our center. Two axial images (T2 weighted), were chosen to realize nine measures. We defined 4 linear indices (MAfhlv: thickness of lateral ventricle; CSI: cortex-skull index; VCI: ventricular-cortex index; BOI: bi occipital index) and 1 surface index (VS.A: volume slice area). Perinatal data were recorded. Sixty-nine infants had a GA (median (interquartile range)) of 30.0 weeks GA (27.0; 30.0) and a birth weight of 1240 grams (986; 1477). MRI was done at 41.0 (40.0; 42.0) weeks post menstrual age (PMA). The inter-investigator reproducibility was good. Twenty one MRI (30.5%) were quoted abnormal. We observed an association with retinopathy of prematurity (OR [95CI] = 4.205 [1.231-14.368]; p = 0.017), surgery for patent ductus arteriosus (OR = 4.688 [1.01-21.89]; p = 0.036), early onset infection (OR = 4.688 [1.004-21.889]; p = 0.036) and neonatal treatment by cefotaxime (OR = 3.222 [1.093-9.497]; p = 0.03). There was a difference for VCI between normal and abnormal MRI (0.412 (0.388; 0.429) vs. 0.432 (0.418; 0.449); p = 0,019); BOI was higher when fossa posterior lesions were observed; VS.A seems to be the best surrogate for cerebral volume, 80% of VS.As' variance being explained by a multiple linear regression model including 7 variables (head circumference at birth and at TEA, PMA, dopamine, ibuprofen treatment, blood and platelets transfusions). These indices, easily and rapidly achievable, seem to be useful but need to be validated in a large population to allow generalization for diagnosis and follow-up of former premature infants.

Correlations of Ventricular Enlargement with Rheologically Active Surfactant Proteins in Cerebrospinal Fluid

Purpose: Surfactant proteins (SPs) are involved in the regulation of rheological properties of body fluids. Concentrations of SPs are altered in the cerebrospinal fluid (CSF) of hydrocephalus patients. The common hallmark of hydrocephalus is enlargement of the brain ventricles. The relationship of both phenomena has not yet been investigated. The aim of this study was to evaluate the association between SP concentrations in the CSF and enlargement of the brain ventricles.

Procedures: Ninty-six individuals (41 healthy subjects and 55 hydrocephalus patients) were included in this retrospective analysis. CSF specimens were analyzed for SP-A, SP-B, SP-C and SP-D concentrations by use of enzyme linked immunosorbent assays (ELISA). Ventricular enlargement was quantified in T2 weighted (T2w) magnetic resonance imaging (MRI) sections using an uni-dimensional (Evans’ Index) and a two-dimensional approach (lateral ventricles area index, LVAI).

Results: CSF-SP concentrations (mean ± standard deviation in ng/ml) were as follows: SP-A 0.71 ± 0.58, SP-B 0.18 ± 0.43, SP-C 0.89 ± 0.77 and SP-D 7.4 ± 5.4. Calculated values of Evans’ Index were 0.37 ± 0.11, a calculation of LVAI resulted in 0.18 ± 0.15 (each mean ± standard deviation). Significant correlations were identified for Evans’ Index with SP-A (r = 0.388, p < 0.001) and SP-C (r = 0.392, p < 0.001), LVAI with SP-A (r = 0.352, p = 0.001), SP-C (r = 0.471, p < 0.001) and SP-D (r = 0.233, p = 0.025). Furthermore, SP-C showed a clear inverse correlation with age (r = −0.357, p = 0.011).

Conclusion: The present study confirmed significant correlations between SPs A, C and D in the CSF with enlargement of the inner CSF spaces. In conclusion, SPs clearly play an important role for CSF rheology. CSF rheology is profoundly altered in hydrocephalic diseases, however, diagnosis and therapy of hydrocephalic conditions are still almost exclusively based on ventricular enlargement. Until now it was unclear, whether the stage of the disease, as represented by the extent of ventricular dilatation, is somehow related to the changes of SP levels in the CSF. Our study is the first to provide evidence that increasing ventriculomegaly is accompanied by enhanced changes of rheologically active compounds in the CSF and therefore introduces completely new aspects for hydrocephalus testing and conservative therapeutic approaches.

Hydrocephalus associated with childhood nonaccidental head trauma

OBJECTIVE

The incidence of posttraumatic ventriculomegaly (PTV) and shunt-dependent hydrocephalus after nonaccidental head trauma (NAHT) is unknown. In the present study, the authors assessed the timing of PTV development, the relationship between PTV and decompressive craniectomy (DC), and whether PTV necessitated placement of a permanent shunt. Also, NAHT/PTV cases were categorized into a temporal profile of delay in admission and evaluated for association with outcomes at discharge.

METHODS

The authors retrospectively reviewed the cases of patients diagnosed with NAHT throughout a 10-year period. Cases in which sequential CT scans had been obtained (n = 28) were evaluated for Evans' index to determine the earliest time ventricular dilation was observed. Discharge outcomes were assessed using the King's Outcome Scale for Childhood Head Injury score.

RESULTS

Thirty-nine percent (11 of 28) of the patients developed PTV. A low admission Glasgow Coma Scale (GCS) score predicted early PTV presentation (within < 3 days) versus a high GCS score (> 1 week). A majority of PTV/NAHT patients presented with a subdural hematoma (both convexity and interhemispheric) and ischemic stroke, but subarachnoid hemorrhage was significantly associated with PTV/NAHT (p = 0.011). Of 6 patients undergoing a DC for intractable intracranial pressure, 4 (67%) developed PTV (p = 0.0366). These patients tended to present with lower GCS scores and develop ventriculomegaly early. Only 2 patients developed hydrocephalus requiring shunt placement.

CONCLUSIONS

PTV presents early after NAHT, particularly after a DC has been performed. However, the authors found that only a few PTV/NAHT patients developed shunt-dependent hydrocephalus.

Role of radiological parameters in predicting overall shunt outcome after ventriculoperitoneal shunt insertion in pediatric patients with obstructive hydrocephalus

OBJECTIVE

Despite significant advances in the medical field and shunt technology, shunt malfunction remains a nightmare of pediatric neurosurgeons. In this setting, the ability to preoperatively predict the probability of shunt malfunction is quite compelling. The authors have compared the preoperative radiological findings in obstructive hydrocephalus and the subsequent clinical course of the patient to determine any association with overall shunt outcome.

METHODS

This retrospective study included all pediatric patients (age < 18 years) who had undergone ventriculoperitoneal shunt insertion for obstructive hydrocephalus. Linear measurements were taken from pre- and postoperative CT or MRI studies to calculate different indices and ratios including Evans' index, frontal horn index (FHI), occipital horn index (OHI), frontooccipital horn ratio (FOHR), and frontooccipital horn index ratio (FOIR). Other morphological features such as bi- or triventriculomegaly, right-left ventricular symmetry, and periventricular lucency (PVL) were also noted. The primary clinical outcomes that were reviewed included the need for shunt revision, time interval to first shunt revision, frequency of shunt revisions, and revision-free survival.

RESULTS

A total of 121 patients were eligible for the analysis. Nearly half of the patients (47.9%) required shunt revision. The presence of PVL was associated with lower revision rates than those in others (39.4% vs 58.2%, p = 0.03). None of the preoperative radiological indices or ratios showed any correlation with shunt revision. Nearly half of the patients with shunt revision required early revision (< 90 days of primary surgery). The reduction in the FOHR was high in patients who required early shunt revision (20.16% in patients with early shunt revision vs 6.4% in patients with late shunt revision, p = 0.009). Nearly half of the patients (48.3%) requiring shunt revision ultimately needed more than one revision procedure. Greater occipital horn dilation on preoperative images was associated with a lower frequency of shunt revision, as dictated by a high OHI and a low FOIR in patients with a single shunt revision as compared with those in patients who required multiple shunt revisions (p = 0.029 and 0.009, respectively). The mean follow-up was 49.9 months. Age was a significant factor affecting shunt revision–free survival. Patients younger than 6 months of age had significantly less revision-free survival than the patients older than 6 months (median survival of 10.1 vs 94.1 months, p = 0.004).

CONCLUSIONS

Preoperative radiological linear indices and ratios do not predict the likelihood of subsequent shunt malfunction. However, patients who required early shunt revision tended to have greater reductions in ventricular volumes on postoperative images. Therefore a greater reduction in ventricular volume is not actually desirable, and a ventricular volume high enough to reduce intracranial pressure is instead to be aimed at for long-term shunt compliance.

Left hemisphere structural connectivity abnormality in pediatric hydrocephalus patients following surgery

Neuroimaging research in surgically treated pediatric hydrocephalus patients remains challenging due to the artifact caused by programmable shunt. Our previous study has demonstrated significant alterations in the whole brain white matter structural connectivity based on diffusion tensor imaging (DTI) and graph theoretical analysis in children with hydrocephalus prior to surgery or in surgically treated children without programmable shunts. This study seeks to investigate the impact of brain injury on the topological features in the left hemisphere, contratelateral to the shunt placement, which will avoid the influence of shunt artifacts and makes further group comparisons feasible for children with programmable shunt valves. Three groups of children (34 in the control group, 12 in the 3-month post-surgery group, and 24 in the 12-month post-surgery group, age between 1 and 18 years) were included in the study. The structural connectivity data processing and analysis were performed based on DTI and graph theoretical analysis. Specific procedures were revised to include only left brain imaging data in normalization, parcellation, and fiber counting from DTI tractography. Our results showed that, when compared to controls, children with hydrocephalus in both the 3-month and 12-month post-surgery groups had significantly lower normalized clustering coefficient, lower small-worldness, and higher global efficiency (all p < 0.05, corrected). At a regional level, both patient groups showed significant alteration in one or more regional connectivity measures in a series of brain regions in the left hemisphere (8 and 10 regions in the 3-month post-surgery and the 12-month post-surgery group, respectively, all p < 0.05, corrected). No significant correlation was found between any of the global or regional measures and the contemporaneous neuropsychological outcomes [the General Adaptive Composite (GAC) from the Adaptive Behavior Assessment System, Second Edition (ABAS-II)]. However, one global network measure (global efficiency) and two regional network measures in the insula (local efficiency and between centrality) tested at 3-month post-surgery were found to correlate with GAC score tested at 12-month post-surgery with statistical significance (all p < 0.05, corrected). Our data showed that the structural connectivity analysis based on DTI and graph theory was sensitive in detecting both global and regional network abnormality when the analysis was conducted in the left hemisphere only. This approach provides a new avenue enabling the application of advanced neuroimaging analysis methods in quantifying brain damage in children with hydrocephalus surgically treated with programmable shunts.

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We studied the structural connectivity of left hemisphere brain network in children with hydrocephalus post-surgery

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Children with hydrocephalus post-surgery had significantly abnormal structural connectivity in the left hemisphere based on graph analysis

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Significant correlation was found between graph measures at 3-months post-surgery and developmental outcome at 12-month post-surgery

Stented endoscopic third ventriculostomy—indications and results

OBJECTIVE

In patients with risk of reclosure of a performed opening in the floor of the third ventricle, a stented endoscopic third ventriculostomy (sETV) was performed to maintain continuous cerebrospinal fluid (CSF) diversion in patients with occlusive hydrocephalus. A retrospective analysis of a patient series is presented.

METHODS

A cohort of nine patients (median age 12 years and 9 months; range 1 month to 25 years and 9 months) was studied retrospectively. Etiology of hydrocephalus was aqueduct stenosis due to tumorous occlusion and tumorous infiltration of the third ventricular floor in seven of nine patients. For two patients with simple aqueductal stenosis, a sETV was performed because of young age of 1 month in one and because of previous ETV failure in the other.

RESULTS

Correct placement of the implanted stent was demonstrated in all treated patients. There was no operative morbidity after the performed sETV. Resolution or improvement of symptoms was achieved in eight of nine patients (88.9%), and failure to control clinical symptoms was observed in one patient (11.1%), who needed subsequent shunt insertion. Decreased ventricular dimensions were seen after the sETV procedure. The median fronto-occipital horn ratio (FOHR) decreased from 0.46 (range 0.43-0.58) to 0.45 (range 0.37 to 0.59) after a median of 3 months and to a median of 0.40 (range 0.30 to 0.50) after 17 months. The median fronto-occipital horn width ratio FOHWR decreased from 0.31 (range 0.22 to 0.52) to 0.28 (range 0.14 to 0.52, p = 0.06) after a median of 3 months and to a median of 0.21 (range 0.09 to 0.36, p < 0.05).

CONCLUSION

sETV is a feasible and safe alternative procedure which when performed with an appropriate trajectory allows treatment of occlusive hydrocephalus with altered anatomy of the third ventricular floor. sETV has been demonstrated to resolve or improve clinical and radiological signs of disturbed CSF circulation.

Structural Image Analysis of the Brain in Neuropsychology Using Magnetic Resonance Imaging (MRI) Techniques

Magnetic resonance imaging (MRI) of the brain provides exceptional image quality for visualization and neuroanatomical classification of brain structure. A variety of image analysis techniques provide both qualitative as well as quantitative methods to relate brain structure with neuropsychological outcome and are reviewed herein. Of particular importance are more automated methods that permit analysis of a broad spectrum of anatomical measures including volume, thickness and shape. The challenge for neuropsychology is which metric to use, for which disorder and the timing of when image analysis methods are applied to assess brain structure and pathology. A basic overview is provided as to the anatomical and pathoanatomical relations of different MRI sequences in assessing normal and abnormal findings. Some interpretive guidelines are offered including factors related to similarity and symmetry of typical brain development along with size-normalcy features of brain anatomy related to function. The review concludes with a detailed example of various quantitative techniques applied to analyzing brain structure for neuropsychological outcome studies in traumatic brain injury.