Ventricular reservoir versus ventriculosubgaleal shunt for posthemorrhagic hydrocephalus in preterm infants: infection risks and ventriculoperitoneal shunt rate

Therapeutic strategies to recover ependymal barrier after inflammatory damage: relevance for recovering neurogenesis during development

The epithelium covering the surfaces of the cerebral ventricular system is known as the ependyma, and is essential for maintaining the physical and functional integrity of the central nervous system. Additionally, the ependyma plays an essential role in neurogenesis, neuroinflammatory modulation and neurodegenerative diseases. Ependyma barrier is severely affected by perinatal hemorrhages and infections that cross the blood brain barrier. The recovery and regeneration of ependyma after damage are key to stabilizing neuroinflammatory and neurodegenerative processes that are critical during early postnatal ages. Unfortunately, there are no effective therapies to regenerate this tissue in human patients. Here, the roles of the ependymal barrier in the context of neurogenesis and homeostasis are reviewed, and future research lines for development of actual therapeutic strategies are discussed.

Variability in the diagnostic and management practices of post-hemorrhagic ventricular dilatation in very preterm infants across Canadian centers and comparison with European practices

OBJECTIVES

To investigate the variability in diagnostic and therapeutic approaches to posthemorrhagic ventricular dilatation (PHVD) among Canadian neonatal centers, and secondary exploration of differences in approaches between Canadian and European practices.

METHODS

We conducted a survey among Canadian tertiary neonatal centers on their local practices for managing very preterm infants with PHVD. The survey covered questions on the diagnostic criteria, timing and type of interventions and resources utilization (transfer to neurosurgical sites and neurodevelopmental follow-up). In a secondary exploration, Canadian responses were compared with responses to the same survey from European centers.

RESULTS

23/30 Canadian centers (77%) completed the survey. There was no consensus among Canadian centers on the criteria used for diagnosing PHVD or to initiate intervention. The therapeutic interventions also vary, both for temporizing procedures or permanent shunting. Compared to European practices, the Canadian approach relied less on the sole use of ultrasound criteria for diagnosing PHVD (43 vs 94%, p < 0.0001) or timing intervention (26 vs 63%, p = 0.007). Majority of European centers intervened early in the development of PHVD based on ultrasound parameters, whereas Canadian centers intervened based on clinical hydrocephalus, with fewer centers performing serial lumbar punctures prior to neurosurgical procedures (40 vs 81%, p = 0.003).

CONCLUSION

Considerable variability exists in diagnosis and management of PHVD in preterm infants among Canadian tertiary centers and between Canadian and European practices. Given the potential implications of the inter-center practice variability on the short- and long-term outcomes of preterm infants with PHVD, efforts towards evidence-based Canada-wide practice standardization are underway.

Epidemiology of post-hemorrhagic ventricular dilatation in very preterm infants

OBJECTIVE

To describe the incidence, trends, management's variability and short-term outcomes of preterm infants with severe post-hemorrhagic ventricular dilatation (sPHVD).

METHODS

We reviewed infants &lt;33 weeks' gestation who had PHVD and were admitted to the Canadian Neonatal Network between 2010 and 2018. We compared perinatal characteristics and short-term outcomes between those with sPHVD and those with mild/moderate PHVD and those with and without ventriculo-peritoneal (VP) shunt.

RESULTS

Of 29,417 infants, 2439 (8%) had PHVD; rate increased from 7.3% in 2010 to 9.6% in 2018 (P = 0.005). Among infants with PHVD, sPHVD (19%) and VP shunt (29%) rates varied significantly across Canadian centers and between geographic regions (P &lt; 0.01 and P = 0.0002). On multivariable analysis, sPHVD was associated with greater mortality, seizures and meningitis compared to mild/moderate PHVD.

CONCLUSIONS

Significant variability in sPHVD and VP shunt rates exists between centers and regions in Canada. sPHVD was associated with increased mortality and morbidities.

Treatment Strategies and Challenges to Avoid Cerebrospinal Fluid Shunting for Pediatric Hydrocephalus

Treatment for pediatric hydrocephalus aims not only to shrink the enlarged ventricle morphologically but also to create an intracranial environment that provides the best neurocognitive development and to deal with various treatment-related problems over a long period of time. Although the primary diseases that cause hydrocephalus are diverse, the ventricular peritoneal shunt has been introduced as the standard treatment for several decades. Nevertheless, complications such as shunt infection and shunt malfunction are unavoidable; the prognosis of neurological function is severely affected by such factors, especially in newborns and infants.

In recent years, treatment concepts have been attempted to avoid shunting, mainly in the context of pediatric cases. In this review, the current role of neuroendoscopic third ventriculostomy for noncommunicating hydrocephalus is discussed and a new therapeutic concept for post intraventricular hemorrhagic hydrocephalus in preterm infants is documented. To avoid shunt placement and achieve good neurodevelopmental outcomes for pediatric hydrocephalus, treatment modalities must be developed.

Diagnosis and Surgical Management of Neonatal Hydrocephalus

Neonatal hydrocephalus represents an important pathological condition with significant impact on medical care and neurocognitive development. This condition requires early recognition, appropriate medical and surgical management, and long-term surveillance by clinicians and pediatric neurosurgeons. Common etiologies of neonatal and infant hydrocephalus include intraventricular hemorrhage related to prematurity with subsequent post-hemorrhagic hydrocephalus, myelomeningocele, and obstructive hydrocephalus due to aqueductal stenosis. Clinical markers of elevated intracranial pressure include rapid increases in head circumference across percentiles, elevation and firmness of the anterior fontanelle, splitting or splaying of cranial sutures, upgaze palsy, lethargy, frequent emesis, or episodic bradycardia (unrelated to other comorbidities). Complementing these clinical markers, imaging modalities used for the diagnosis of neonatal hydrocephalus include head ultrasonography, brain magnetic resonance imaging, and head computed tomography in urgent or emergent situations. Following diagnosis, temporizing measures may be employed prior to definitive treatment and include ventricular access device or ventriculo-subgaleal shunt insertion. Definitive surgical management involves permanent cerebrospinal fluid (CSF) diversion via CSF shunt insertion, or endoscopic third ventriculostomy with or without choroid plexus cauterization. Surgical decision-making and approaches vary based on patient age, hydrocephalus etiology, neuroanatomy, imaging findings, and medical comorbidities. Indications, surgical techniques, and clinical outcomes of these procedures continue to evolve and elicit significant attention in the research environment. In this review we describe the epidemiology, pathophysiology, clinical markers, imaging findings, early management, definitive surgical management, and clinical outcomes of pediatric patients with neonatal hydrocephalus.

Development of machine learning-based predictor algorithm for conversion of an Ommaya reservoir to a permanent cerebrospinal fluid shunt in preterm posthemorrhagic hydrocephalus

BACKGROUND

Ommaya reservoir can be used to treat posthemorrhagic hydrocephalus secondary to intraventricular hemorrhage of prematurity until an acceptable weight can be obtained to place a permanent shunt. Identifying newborns at higher risk of developing shunt conversion may improve the management of these patients.

OBJECTIVE

Develop a predictive algorithm for the conversion of an Ommaya reservoir to a permanent shunt using artificial intelligence techniques and "classical" statistics.

METHODS

Database of 43 preterm patients weighing ≤ 1500g with posthemorrhagic hydrocephalus (Papile Grades III and IV with Levene index > 4 mm above the 97th percentile) managed with Ommaya reservoir at our institution between 2002 and 2017 was used to train a KNN algorithm. Validation of results with cross validation technique. Three scenarios were calculated. 1: considering all features regardless whether or not they are correlated with the output variable. 2: consider the features as predictors if they have a correlation greater than a 30% with the output variable. 3: consider the output of the previous analysis.

RESULTS

Results show that when considering the outputs of a previous multivariate analysis the algorithm reaches an 86% of cross validation accuracy.

CONCLUSION

The use of machine learning-based algorithms can help in the early identification of patients with permanent need of shunt. We present the development of a predictive algorithm for permanent shunt with an accuracy of 86%, accuracy of the algorithm can be improved with larger volume of data and previous analysis.

The role of blood product removal in intraventricular hemorrhage of prematurity: a meta-analysis of the clinical evidence

INTRODUCTION

Premature neonates have a high risk of intraventricular hemorrhage (IVH) at birth, the blood products of which activate inflammatory cascades that can cause hydrocephalus and long-term neurological morbidities and sequelae. However, there is no consensus for one treatment strategy. While the mainstay of treatment involves CSF diversion to reduce intracranial pressure, a number of interventions focus on blood product removal at various stages including extraventricular drains (EVD), intra-ventricular thrombolytics, drainage-irrigation-fibrinolytic therapy (DRIFT), and neuroendoscopic lavage (NEL).

METHODS

We performed a systematic review and meta-analysis to compare the risks and benefits commonly associated with active blood product removal treatment strategies. We searched MEDLINE, Embase, Scopus, Cochrane Library, and CINAHL databases through Dec 2020 for articles reporting on outcomes of EVDs, thrombolytics, DRIFT, and NEL. Outcomes of interest were rate of conversion to ventriculoperitoneal shunt (VPS), infection, mortality, secondary hemorrhage, and cognitive disability.

RESULTS

Of the 10,398 articles identified in the search, 23 full-text articles representing 22 cohorts and 530 patients were included for meta-analysis. These articles included retrospective, prospective, and randomized controlled studies on the use of EVDs (n = 7), thrombolytics (n = 8), DRIFT therapy (n = 3), and NEL (n = 5). Pooled rates of reported outcomes for EVD, thrombolytics, DRIFT, and NEL for ventriculoperitoneal shunt (VPS) placement were 51.1%, 43.3%, 34.3%, and 54.8%; for infection, 15.4%, 12.5%, 4.7%, and 11.0%; for mortality, 20.0%, 11.6%, 6.0%, and 4.9%; for secondary hemorrhage, 5.8%, 7.8%, 20.0%, and 6.9%; for cognitive impairment, 52.6%, 50.0%, 53.7%, and 50.9%. Meta-regression using type of treatment as a categorical covariate showed no effect of treatment modality on rate of VPS conversion or cognitive disability.

CONCLUSION

There was a significant effect of treatment modality on secondary hemorrhage and mortality; however, mortality was no longer significant after adjusting for year of publication. Re-hemorrhage rate was significantly higher for DRIFT (p < 0.001) but did not differ among the other modalities. NEL also had lower mortality relative to EVD (p < 0.001) and thrombolytics (p = 0.013), which was no longer significant after adjusting for year of publication. Thus, NEL appears to be safer than DRIFT in terms of risk of hemorrhage, and not different than other blood-product removal strategies in terms of mortality. Outcomes-in terms of shunting and cognitive impairment-did not differ. Later year of publication was predictive of lower rates of mortality, but not the other outcome variables. Further prospective and randomized studies will be necessary to directly compare NEL with other temporizing procedures.

Neuroendoscopic lavage for the management of neonatal post-haemorrhagic hydrocephalus: a retrospective series

INTRODUCTION

Intraventricular haemorrhage (IVH) is a common complication of preterm birth, and optimal treatment remains uncertain. Neuroendoscopic lavage (NEL) has gained interest as a method for removal of intraventricular haematoma, with outcomes suggesting it to be safe and potentially effective.

METHODS

A retrospective review was carried identifying infants who underwent NEL for post-IVH hydrocephalus at our institution. Data was extracted on patient baseline demographics, comorbidities, complications, re-operation requirement, and neurodevelopmental outcomes.

RESULTS

Twenty-six patients (17 male) were identified, who underwent NEL at a mean age of 39 weeks and 4 days. Eighteen patients underwent simultaneous endoscopic third ventriculostomy (ETV). Mean patient follow-up was 57.7 months ± 11.8 months. A total of 17/26 patients went on to require a ventriculoperitoneal shunt (VPS). Nine patients did not require further surgical management of hydrocephalus; all had been managed with NEL + ETV. The relative risk of requiring VPS with NEL + ETV compared with NEL alone was 0.500 (CI: 0.315-0.794; p = 0.0033). The 24-month survival rate of VPS inserted following NEL was 64.7%. Exactly 5/26 (19.2%) had post-procedure complications: 2 CSF leaks (7.7%), 2 infections (7.7%), and 1 rebleed within 72 h of NEL (3.8%). On long-term follow-up, 22/25 patients achieved good motor outcome, either walking independently or with mobility aids. A total of 8/15 children attended mainstream schooling with adaption.

DISCUSSION

NEL is safe and potentially efficacious treatment for neonatal IVH. The procedure may reduce shunt dependence and, for those who require CSF diversion, improve shunt survival. Neurodevelopmentally, good motor and cognitive outcome can be achieved.

The Cost of Serial Cerebrospinal Fluid Aspirations between Ventricular Access Device and Ventriculosubgaleal Shunt for Treatment of Posthemorrhagic Ventricular Dilatation in Premature Infants

INTRODUCTION

Ventriculosubgaleal shunts (VSGSs) require fewer cerebrospinal (CSF) aspirations than ventricular access devices (VADs) for temporization of posthemorrhagic ventricular dilatation (PHVD) in preterm infants. Cost of postoperative CSF aspiration has not been quantified.

METHODS

We reviewed CSF aspiration and laboratory studies obtained in preterm infants with PHVD and VAD at our institution between 2009 and 2020. Cost per aspiration was calculated for materials, labs, and Medicare fee schedule for ventricular puncture through implanted reservoir. We searched PubMed, Cochrane Library, Embase, CINAHL, and Web of Science for meta-analysis of pooled mean number of CSF aspirations and proportion of patients requiring aspiration.

RESULTS

Thirty-five preterm infants with PHVD had VAD placed with 22.2 ± 18.4 aspirations per patient. Labs were obtained after every aspiration per local protocol. Cost per aspiration at our institution was USD 935.51. Of 269 published studies, 77 reported on VAD, 29 VSGS, and 13 both. Five studies on VAD (including the current study) had a pooled mean of 25.8 aspirations per patient (95% CI: 16.7-34.8). One study on VSGS reported a mean of 1.6 ± 1.7 aspirations. Three studies on VAD (including the current study) had a pooled proportion of 97.4% of patients requiring aspirations (95% CI: 87.9-99.5). Four studies on VSGS had a pooled proportion of 36.5% requiring aspirations (95% CI: 26.9-47.2). Frequency of lab draws ranged from weekly to daily. Based on costs at our institution, mean number of aspirations, and proportion of patients requiring aspirations, cost difference ranged between USD 4,243 and 23,235 per patient and USD 500,903 and 2.36 million per 100 patients depending on frequency of taps and Medicare locality.

DISCUSSION/CONCLUSION

Lower number of CSF aspirations using VSGS can be associated with considerably lower cost compared to VAD.

Timing of Temporizing Neurosurgical Treatment in Relation to Shunting and Neurodevelopmental Outcomes in Posthemorrhagic Ventricular Dilatation of Prematurity: A Meta-analysis

OBJECTIVE

To determine the relationship between timing of initiation of temporizing neurosurgical treatment and rates of ventriculoperitoneal shunt (VPS) and neurodevelopmental impairment in premature infants with post-hemorrhagic ventricular dilatation (PHVD).

STUDY DESIGN

We searched MEDLINE, EMBASE, CINAHL, Web of Science, the Cochrane Database of Systematic Reviews, and the Cochrane Center Register of Controlled Trials for studies that reported on premature infants with PHVD who underwent a temporizing neurosurgical procedure. The timing of the temporizing neurosurgical procedure, gestational age, birth weight, outcomes of conversion to VPS, moderate-to-severe neurodevelopmental impairment, infection, temporizing neurosurgical procedure revision, and death at discharge were extracted.

RESULTS

Sixty-two full-length articles and 6 conference abstracts (n = 2533 patients) published through November 2020 were included. Pooled rate for conversion to VPS was 60.5% (95% CI, 54.9-65.8), moderate-severe neurodevelopmental impairment 34.8% (95% CI, 27.4-42.9), infection 8.2% (95% CI, 6.7-10.1), revision 14.6% (95% CI, 10.4-20.1), and death 12.9% (95% CI, 10.2-16.4). The average age at temporizing neurosurgical procedure was 24.2 ± 11.3 days. On meta-regression, older age at temporizing neurosurgical procedure was a predictor of conversion to VPS (P < .001) and neurodevelopmental impairment (P < .01). Later year of publication predicted increased survival (P < .01) and external ventricular drains were associated with more revisions (P = .001). Tests for heterogeneity reached significance for all outcomes and a qualitative review showed heterogeneity in the study inclusion and diagnosis criteria for PHVD and initiation of temporizing neurosurgical procedure.

CONCLUSIONS

Later timing of temporizing neurosurgical procedure predicted higher rates of conversion to VPS and moderate-severe neurodevelopmental impairment. Outcomes were often reported relative to the number of patients who underwent a temporizing neurosurgical procedure and the criteria for study inclusion and the initiation of temporizing neurosurgical procedure varied across institutions. There is need for more comprehensive outcome reporting that includes all infants with PHVD regardless of treatment.

Predictor of a permanent shunt after treatment of external ventricular draining in pediatric postinfective hydrocephalus-a retrospective cohort study

PURPOSE

To assess the therapeutic efficacy of external ventricular draining (EVD) and to predict the need for permanent shunts in infants with postinfective hydrocephalus (PIHC).

METHODS

This is a retrospective study of infants diagnosed with PIHC and treated by EVD between January 2013 and December 2017 at the Children's Hospital of Fudan University. Clinical, laboratory, and imaging data were collected and analyzed to identify independent risk factors by logistic regression analyses. The predictor was evaluated using the area under the curve (AUC) of the receiver operating characteristic (ROC) curves.

RESULTS

In total, 48 patients were identified, and 31 cases (64.5%) had a permanent shunt. EVD was effective in accelerating cerebrospinal fluid purification. In the permanent shunt group, the duration of EVD was significantly longer (28.5 ± 5.2 vs 14.9 ± 3.0 P < 0.05) and the frontal and occipital horn ratio (FOHR) at 7-10 days after EVD was significantly higher (0.57 ± 0.01 vs 0.48 ± 0.01 P < 0.001). The FOHR at 7-10 days after EVD predicts the need for a permanent shunt with an area under the ROC curve of 0.818.

CONCLUSION

EVD was effective for purification of CSF, whereas a permanent shunt was needed for more than half of the patients. The FOHR at 7-10 days after EVD may be a strong predictor for a permanent shunt.

Safety of Ventricular Reservoir Sampling in Pediatric Posthemorrhagic Hydrocephalus Patients: Institutional Experience and Review of the Literature

ABSTRACT

INTRODUCTION: Posthemorrhagic hydrocephalus (PHH) is a common disease process encountered in neonates. Management often includes cerebrospinal fluid (CSF) aspiration through ventricular access devices (VADs). However, a common concern surrounding serial access of implanted subcutaneous reservoirs includes introduction of infection. In addition, there is great variability in aseptic technique. Therefore, the authors sought to evaluate the incidence of VAD access-associated infections in the literature and compare them with the rate of infection found at our institution. We also highlight the use of a preassembled VAD access kit and standardized access protocol, as well as the role of provider education, in maintaining safety and sterility during serial VAD access. METHODS: A single-institution retrospective review was performed for PHH patients younger than 1 year old undergoing serial CSF aspirations via implanted VADs (2009-2019). Patients were excluded if they had a ventriculoperitoneal shunt placed as primary intervention. MEDLINE search for reports of serial VAD access in PHH was also performed. Reports were excluded if they did not include full-text articles in the English literature. RESULTS: At our institution, subcutaneous reservoirs were placed in 37 neonates with PHH for serial CSF aspiration. No infections occurred after a total of 630 taps (average, 17 taps per reservoir; range, 0-83) and 10 420 collective reservoir days (average, 282 per patient; range, 6-3700). Only 2 reservoirs required revision for malfunction. Serial VAD taps for PHH were described in 14 articles in the medical literature, with 7.9% (n = 47/592) of patients reported with tap-related infectious complications. CONCLUSION: A standardized VAD access kit, along with stringent adherence to access protocol, can significantly minimize risk of infection associated with serial VAD access. These principles can be generalized to percutaneous aspiration of CSF from subcutaneous reservoirs placed for other indications to promote safety and sterility of this common procedure.

Efficacy and safety of intraventricular fibrinolytic therapy for post-intraventricular hemorrhagic hydrocephalus in extreme low birth weight infants: a preliminary clinical study

PURPOSE

To evaluate the efficacy and safety of our unique therapy for treating post-intraventricular hemorrhagic hydrocephalus (PIVHH) in low birth weight infants (LBWls) through an early stage fibrinolytic therapeutic strategy involving urokinase (UK) injection into the lateral ventricle, called the "Ventricular Lavage (VL) therapy."

METHODS

Overall, 43 consecutive infants with PIVHH were included. Most were extremely LBWIs (n = 39). Other cases included very LBWIs (n = 2) and full-term infants (n = 2). VL therapy involved continuous external ventricular drainage (EVD) management using a very fine catheter and intermittent slow injection of 6000 IU of UK every 3-6 h to actively dissolve hematomas.

RESULTS

Early EVD management (within 3 weeks of IVH onset) was performed in 25 infants, with combination VL therapy in 21 infants. Five initiated late EVD management (≥ 3 weeks after IVH onset); the remaining 13 were treated conservatively for several weeks, delaying surgical intervention. Eighteen of 21 (86%) infants who received VL therapy did not require permanent shunt surgery. There were no serious complications, including the absence of secondary hemorrhage and infection. Two-thirds of the infants treated in the late stages required permanent shunt, and various shunt-related complications frequently occurred. A good outcome occurred in 13/17 infants in the early treatment group, despite most subjects having an IVH grade IV, and in 6/15 in the late treatment group.

CONCLUSIONS

Permanent shunt surgery needs were dramatically reduced following early VL therapy, and functional outcomes were favorable. VL therapy might be a promising strategy that could lead to the development of new treatments for PIVHH.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Treatment of Pediatric Hydrocephalus: Update of the 2014 Guidelines

BACKGROUND

The Congress of Neurological Surgeons reviews its guidelines according to the Institute of Medicine's recommended best practice of reviewing guidelines every 5 yrs. The authors performed a planned 5-yr review of the medical literature used to develop the “Pediatric hydrocephalus: systematic literature review and evidence-based guidelines” and determined the need for an update to the original guideline based on new available evidence.

OBJECTIVE

To perform an update to include the current medical literature for the “Pediatric hydrocephalus: systematic literature review and evidence-based guidelines”, originally published in 2014.

METHODS

The Guidelines Task Force used the search terms and strategies consistent with the original guidelines to search PubMed and Cochrane Central for relevant literature published between March 2012 and November 2019. The same inclusion/exclusion criteria were also used to screen abstracts and to perform the full-text review. Full text articles were then reviewed and when appropriate, included as evidence and recommendations were added or changed accordingly.

RESULTS

A total of 41 studies yielded by the updated search met inclusion criteria and were included in this update.

CONCLUSION

New literature resulting from the update yielded a new recommendation in Part 2, which states that neuro-endoscopic lavage is a feasible and safe option for the removal of intraventricular clots and may lower the rate of shunt placement (Level III). Additionally a recommendation in part 7 of the guideline now states that antibiotic-impregnated shunt tubing reduces the risk of shunt infection compared with conventional silicone hardware and should be used for children who require placement of a shunt (Level I). &lt;https://www.cns.org/guidelines/browse-guidelines-detail/pediatric-hydrocephalus-guideline&gt;

A comparison between flow-regulated and adjustable valves used in hydrocephalus during infancy

INTRODUCTION

Ventriculoperitoneal shunt insertion during the neonatal period and early infancy is associated with a high rate of shunt failure when compared to the adult population. Furthermore, the function of flow-regulated valves and differential pressure valves may be different in neonatal hydrocephalus.

METHODS

A retrospective case series of all primary shunt procedures carried out during or immediately following the neonatal period, from August 2011 to February 2018 at Sheffield Children's Hospital. The total sample size was 55. This included 34 patients with adjustable valves (Miethke ProGav) and 21 with flow-regulated valves (Orbis-Sigma); however, only 53 had adequate follow-up.

RESULTS

The overall 1 year shunt survival was 34% (18/53), and there was no significant difference depending on which shunt valve was implanted. The primary shunt infection rate was 11% (6/53) with S. aureus being the most common causative organism. During the first year of life, clinical signs of shunt overdrainage were seen more frequently in patients with adjustable valves than in those with flow-regulated valves (59% [19/32] versus 24% [5/21], p = 0.02). Furthermore, 2 patients in the adjustable valve group developed sagittal craniosynostosis secondary to shunt overdrainage.

CONCLUSION

Shunt failure is high when inserted during or immediately following the neonatal period. Overdrainage may be less common in patients with flow-regulated valves. However, if overdrainage is observed, adjusting the setting of a differential pressure valve can effectively treat the overdrainage without the need for invasive shunt revision surgery.

Standardizing treatment of preterm infants with post-hemorrhagic hydrocephalus at a single institution with a multidisciplinary team

BACKGROUND

Preterm infants with post-hemorrhagic hydrocephalus (PHH) are often treated with temporizing measures such as ventricular access devices (VADs) in order to drain cerebrospinal fluid (CSF) prior to permanent diversion with ventriculoperitoneal shunt (VPS) placement.

LOCAL PROBLEM

There is little consensus on the timing and management of VADs and VPSs. This leads to marked practice variations among treating services that can adversely affect patient outcomes.

METHODS

This is a quality improvement study evaluating practices from February 2011 to September 2017 including infants with PHH in a single level IV NICU.

INTERVENTIONS

A multidisciplinary team created a local clinical pathway modified from the Hydrocephalus Clinical Research Network's Shunting Outcomes in Post-Hemorrhagic Hydrocephalus protocol to manage infants with PHH. Methods of CSF diversion and shunt timing were based on weight. Neonatal care providers performed VAD aspiration; timing was guided by imaging and clinical exam criteria. Surgical procedures were performed in the NICU.

RESULTS

There were 78 patients eligible for the study. Prior to pathway implementation, infections occurred in 4% of VAD and 3% of VPS patients. There have been no infections since inception of the pathway. With pathway implementation, treatment compliance improved from 55 to 86% while conversion compliance rate improved from 89 to 100%.

CONCLUSIONS

Standardization of care for PHH infants leads to improvement in patient outcomes such as a decrease in time to VAD placement. Reservoir aspirations by the neonatology team did not result in an increase in infection rate.

Neuroendoscopic lavage for the management of posthemorrhagic hydrocephalus in preterm infants: safety, effectivity, and lessons learned

OBJECTIVE

Treatment of posthemorrhagic hydrocephalus in preterm infants is a matter of debate among pediatric neurosurgeons. Neuroendoscopic lavage (NEL) has been proposed as a suitable technique for the management of this pathology. The authors present their experience with 46 patients treated with NEL after germinal matrix hemorrhage, describe their technique, and analyze the outcomes.

METHODS

A retrospective analysis of patients affected by grade III or IV intraventricular hemorrhage (IVH) treated with NEL was performed. Nonmodifiable risk factors such as gestational age, weight at birth, modified Papile grade, and intercurrent diseases were reviewed. Safety analysis was performed, evaluating the incidence of postoperative complications. Effectivity was measured using radiological (frontal horn index and white matter injury), CSF biochemical (proteins, blood, and cellularity), and clinical variables. Permanent shunt rate and shunt survival were analyzed. The motor outcome was measured using the Gross Motor Function Classification System (GMFCS) at 18-24 months, and the neurocognitive outcome was evaluated according to the grade of adaptation to schooling.

RESULTS

Forty-six patients met the inclusion criteria. Patients were treated with a single NEL in 21 cases, 2 lavages in 13 cases, and 3 lavages in 12 cases. The mean gestational age at birth was 30.04 weeks, and the mean weight at birth was 1671.86 g. Hyaline membrane disease was described in 4.8% of the cases, hematological sepsis in 43.47%, persistent ductus arteriosus in 23.9%, and necrotizing enterocolitis in 10.9% of the cases. Modified Papile grade III and IV IVHs were observed in 60.9% and 39.1% of the cases, respectively. Postoperative infection was diagnosed in 10 of the 46 cases, CSF leak in 6, and rebleeding in 3. The mean frontal horn index decreased from 49.54 mm to 45.50 mm after NEL. No white matter injury was observed in 18 of 46 patients, focal injury was described in 13 patients, and diffuse bilateral white matter injury was observed in 15 patients. All CSF biochemical levels improved after lavage. The shunt rate was 58.7%, and shunt survival at 1 year was 50%. GMFCS grades I, II, III, IV, and V were observed in 44.74%, 21.05%, 2.63%, 15.79%, and 15.79% of patients, respectively. Good neurocognitive results were observed in 53.3% of the cases.

CONCLUSIONS

Neuroendoscopic lavage was a suitable alternative for the management of IVH in preterm infants in our series. Good motor and neurocognitive results were achieved by this technique, and the permanent shunt rate was reduced compared with historical controls.

Surgical management of intraventricular hemorrhage and posthemorrhagic hydrocephalus in premature infants

Perinatal intraventricular hemorrhage (IVH) with or without development of posthemorrhagic hydrocephalus (PHH) in premature neonates may lead to severe neurological disability. Although the percentage of preterm infants developing IVH has been greatly reduced in the last three decades, increased survival of these very immature infants has meant that large IVH with subsequent PHH is still a serious unsolved problem. Early cerebrospinal fluid diversion as a temporizing measure or a permanent shunt is the treatment of choice. This review summarizes the surgical modalities, techniques, and their complications in the management of IVH and PHH in premature infants. Though there is no level-one evidence to support the superiority of any of the currently available managements in the initial treatment of PHH over others, this review aims to provide pediatric neurosurgeons a comprehensive understanding of the pros and cons of various surgical treatment modalities, focusing on the temporizing measures before the infants is heavy enough to undergo ventriculoperitoneal shunt insertion. Based on the patient's condition, the facility and man power of the institution with minimal complication rate, the pediatric neurosurgeons may choose the best initial approach for the management of IVH and PHH in premature infants.

Risk factors associated with conversion of an Ommaya reservoir to a permanent cerebrospinal fluid shunt in preterm posthemorrhagic hydrocephalus

OBJECTIVE

A considerable percentage of preterm infants with posthemorrhagic hydrocephalus initially managed with an Ommaya reservoir require a permanent CSF shunt. The objective of the study was to analyze possible risk factors associated with the need for converting an Ommaya reservoir to a permanent shunt.

METHODS

The authors retrospectively reviewed the clinical records of premature infants weighing 1500 g or less with posthemorrhagic hydrocephalus (Papile grades III and IV) managed with an Ommaya reservoir at their institution between 2002 and 2017.

RESULTS

Forty-six patients received an Ommaya reservoir. Five patients (10.9%) were excluded due to intraventricular infection during management with an Ommaya reservoir. Average gestational age and weight for the remaining 41 patients was 27 ± 1.8 weeks and 987 ± 209 grams, respectively. Thirty patients required a permanent shunt and 11 patients did not require a permanent shunt. The conversion rate from an Ommaya reservoir to a permanent shunt was 76.1%. Symptomatic persistent ductus arteriosus (PDA) was more frequent in the nonpermanent shunt group than in the shunt group (88.9% vs 50%, p = 0.04). The need for extraction of more than 10 ml/kg per day of CSF through the Ommaya reservoir was lower in the nonpermanent shunt group than in the shunt group (9.1% vs 51.7%, p = 0.015). CSF lactate was lower in the nonpermanent group than in the shunt group (mean 2.48 mg/dl vs 3.19 mg/dl; p = 0.004). A cutoff value of ≥ 2.8 mg/dl CSF lactate predicted the need for a permanent shunt with sensitivity and specificity of 82.4% and 80%, respectively. There were no significant differences in gestational age, sex, weight, Papile grade, ventricular index, or other biochemical markers. After the multivariate analysis, only CSF lactate ≥ 2.8 mg/dl was associated with a higher conversion rate to a permanent shunt.

CONCLUSIONS

This study showed that a high level of CSF lactate, absence of symptomatic PDA, and a higher CSF extraction requirement were associated with a higher likelihood of implanting a permanent CSF shunt. The authors believe these findings should be considered in future studies.

Bedside placement of ventricular access devices under local anaesthesia in neonates with posthaemorrhagic hydrocephalus: preliminary experience

PURPOSE

Posthaemorrhagic ventricular dilatation in preterm infants is primarily treated using temporising measures, of which the placement of a ventricular access device (VAD) is one option. Permanent shunt dependency rates are high, though vary widely. In order to improve the treatment burden and lower shunt dependency rates, we implemented several changes over the years. One of these changes involves the setting of the surgery from general anaesthesia in the OR to local anaesthesia in bed at the neonatal intensive care unit (NICU), which may seem counterintuitive to many. In this article, we describe our surgical technique and present the results of this regimen and compare it to our previous techniques.

METHODS

Retrospective study of a consecutive series of 37 neonates with posthaemorrhagic ventricular dilatation (PHVD) treated using a VAD, with a cohort I (n = 13) treated from 2004 to 2008 under general anaesthesia in the OR, cohort II (n = 11) treated from 2009 to 2013 under general anaesthesia in the NICU and cohort III (n = 13) treated from December 2013 to December 2017 under local anaesthesia on the NICU.

RESULTS

The overall infection rate was 14%; the VAD revision rate was 22% and did not differ significantly between the cohorts. Procedures under local anaesthesia never required conversion to general anaesthesia and were well tolerated. After an average of 33 tapping days, 38% of the neonates received a permanent ventriculoperitoneal (VP) shunt. The permanent VP shunt rate was 9% with VAD placement under local anaesthesia and 52% when performed under general anaesthesia (p = 0.02).

CONCLUSION

Bedside placement of VADs for PHVD under local anaesthesia in neonates is a low-risk, well-tolerated procedure that results in at least equal results to surgery performed under general anaesthesia and/or performed in an OR.

Ventriculosubgaleal shunting-a comprehensive review and over two-decade surgical experience

INTRODUCTION

The subgaleal space is the fibroareolar layer found between the galea aponeurotica and the periosteum of the scalp. Due to its elastic and absorptive capabilities, the subgaleal space can be used as a shunt to drain excess cerebrospinal fluid from the ventricles. A subgaleal shunt consists of a shunt tube with one end in the lateral ventricles while the other end is inserted into the subgaleal space of the scalp. This will allow for the collection and absorption of excess cerebrospinal fluid. Indications for ventriculosubgaleal shunting (VSG) include acute head trauma, subdural hematoma, and malignancies.

DISCUSSION

VSG shunt is particularly advantageous for premature infants suffering from post-hemorrhagic hydrocephalus due to their inability to tolerate long-term management such as a ventriculoperitoneal shunt. Complications include infection and shunt blockage. In comparison with other short-term treatments of hydrocephalus, the VSG exhibits significant advantages in the drainage of excess cerebrospinal fluid. VSG shunt is associated with lower infection rates than other external ventricular drain due to the closed system of CSF drainage and lack of external tubes.

CONCLUSION

This review discusses the advantages and disadvantages of the VSG shunt, as well as our personal experience with the procedure.

Outcome of Ventriculosubgaleal Shunt in the Management of Infectious and Non-infectious Hydrocephalus in Pre-term Infants

Background:

Hydrocephalus in premature infants is an onerous disease. In such situations, choosing the best option for cerebrospinal fluid (CSF) diversion is difficult. Ventriculosubgaleal shunt is an effective method of temporary CSF diversion in such situations. In this retrospective study, we compare the outcome of ventriculosubgaleal shunt in premature infants with hydrocephalus of infectious and noninfectious etiology.

Materials and Methods:

All premature children with hydrocephalus secondary to various etiologies who underwent ventriculosubgaleal shunt were studied. The participants were grouped into two depending upon the etiology of hydrocephalus: Group 1 (infectious) and Group 2 (non-infectious). The primary outcome was a successful conversion to ventriculoperitoneal shunt (VPS) and the secondary outcome was mortality. Data were entered into statistical software SPSS version 16 and appropriate statistical analysis was performed to conclude any statistical significance between groups.

Results:

The study included 16 infants among whom 9 were in the infectious group and 7 in the non-infectious group. Primary end point of conversion to VPS was achieved in 55.5% of patients in group 1 and 85.7% in group 2. The secondary end point, i.e., mortality was observed in 44.4% of patients in group 1 and 14.2% in group 2. The average duration during which this was achieved was 40 days (range 20–60 days) in group 1 and 25 days (range 20–30 days) in group 2.

Conclusion:

Ventriculosubgaleal shunt is a safe and effective procedure in infants awaiting definitive VPS for hydrocephalus of infectious as well as noninfectious origin. There was no statistical difference in the rate of successful conversion to a permanent VPS from ventriculosubgaleal shunt in hydrocephalus of either etiologies. Complications and time for successful conversion were more in postmeningitic hydrocephalus.

A clinical scoring system to predict the development of intraventricular hemorrhage (IVH) in premature infants

OBJECTıVE: The aim of this study is to develop a scoring system for the prediction of intraventricular hemorrhage (IVH) in preterm infants in the first 7 days of life.

METHODS

A prospective, clinical study was conducted in Bahcesehir University, Medical Park Goztepe Hospital Neonatal Intensive Care Unit, with the enrollment of 144 preterm infants with gestational age between 24 and 34 weeks. All preterms were followed up for IVH after birth until the 4th week of life. The demographic characteristics and clinical risk factors were noted. Risk factors were analyzed. The score was established after logistic regression analysis, considering the impact of each variable on the occurrence of IVH within the first 7 days of life. The IVH scores were further applied prospectively to 89 preterm infants as validation cohort.

RESULTS

Low gestational age (GA), low Apgar score, and having bleeding diathesis were the most important risk factors for IVH. According to these risk factors, a scoring system was developed for IVH ranged from 0 to 5. According to the risk ratios (RR) obtained from the logistic regression model, low GA (≤ 28 gestational week), presence of bleeding diathesis within 7 days, and low Apgar score increased the risk of IVH (RR = 3.32 for GA ≤ 28 gestational week, RR = 6.7 for presence of bleeding diathesis in 7th day, RR = 3 for having low Apgar score). The score was validated successfully in 89 infants. The area under ROC curve was 0.85 for derivation cohort and 0.807 for validation cohort. The predictive ability of the IVH score for derivation and validation cohort was calculated. The negative predictive values of a score less than 4 were 96.4 and 59.1%. CONCLUSıON: Concerning IVH-related sequelae which continue to be a major public health problem, we have developed a feasible predictive model for evaluating the risk for developing IVH for preterm infants in the first 7 days of life.

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.

Shunting outcomes in posthemorrhagic hydrocephalus: results of a Hydrocephalus Clinical Research Network prospective cohort study

OBJECTIVE Previous Hydrocephalus Clinical Research Network (HCRN) retrospective studies have shown a 15% difference in rates of conversion to permanent shunts with the use of ventriculosubgaleal shunts (VSGSs) versus ventricular reservoirs (VRs) as temporization procedures in the treatment of hydrocephalus due to high-grade intraventricular hemorrhage (IVH) of prematurity. Further research in the same study line revealed a strong influence of center-specific decision-making on shunt outcomes. The primary goal of this prospective study was to standardize decision-making across centers to determine true procedural superiority, if any, of VSGS versus VR as a temporization procedure in high-grade IVH of prematurity. METHODS The HCRN conducted a prospective cohort study across 6 centers with an approximate 1.5- to 3-year accrual period (depending on center) followed by 6 months of follow-up. Infants with premature birth, who weighed less than 1500 g, had Grade 3 or 4 IVH of prematurity, and had more than 72 hours of life expectancy were included in the study. Based on a priori consensus, decisions were standardized regarding the timing of initial surgical treatment, upfront shunt versus temporization procedure (VR or VSGS), and when to convert a VR or VSGS to a permanent shunt. Physical examination assessment and surgical technique were also standardized. The primary outcome was the proportion of infants who underwent conversion to a permanent shunt. The major secondary outcomes of interest included infection and other complication rates. RESULTS One hundred forty-five premature infants were enrolled and met criteria for analysis. Using the standardized decision rubrics, 28 infants never reached the threshold for treatment, 11 initially received permanent shunts, 4 were initially treated with endoscopic third ventriculostomy (ETV), and 102 underwent a temporization procedure (36 with VSGSs and 66 with VRs). The 2 temporization cohorts were similar in terms of sex, race, IVH grade, head (orbitofrontal) circumference, and ventricular size at temporization. There were statistically significant differences noted between groups in gestational age, birth weight, and bilaterality of clot burden that were controlled for in post hoc analysis. By Kaplan-Meier analysis, the 180-day rates of conversion to permanent shunts were 63.5% for VSGS and 74.0% for VR (p = 0.36, log-rank test). The infection rate for VSGS was 14% (5/36) and for VR was 17% (11/66; p = 0.71). The overall compliance rate with the standardized decision rubrics was noted to be 90% for all surgeons. CONCLUSIONS A standardized protocol was instituted across all centers of the HCRN. Compliance was high. Choice of temporization techniques in premature infants with IVH does not appear to influence rates of conversion to permanent ventricular CSF diversion. Once management decisions and surgical techniques are standardized across HCRN sites, thus minimizing center effect, the observed difference in conversion rates between VSGSs and VRs is mitigated.

Trends in hospitalization of preterm infants with intraventricular hemorrhage and hydrocephalus in the United States, 2000-2010

OBJECT Even with improved prenatal and neonatal care, intraventricular hemorrhage (IVH) occurs in approximately 25%-30% of preterm infants, with a subset of these patients developing hydrocephalus. This study was undertaken to describe current trends in hospitalization of preterm infants with posthemorrhagic hydrocephalus (PHH) using the Nationwide Inpatient Sample (NIS) and the Kids' Inpatient Database (KID). METHODS The KID and NIS were combined to generate data for the years 2000-2010. All neonatal discharges with ICD-9-CM codes for preterm birth with IVH alone or with IVH and hydrocephalus were included. RESULTS There were 147,823 preterm neonates with IVH, and 9% of this group developed hydrocephalus during the same admission. Of patients with Grade 3 and 4 IVH, 25% and 28%, respectively, developed hydrocephalus in comparison with 1% and 4% of patients with Grade 1 and 2 IVH, respectively. Thirty-eight percent of patients with PHH had permanent ventricular shunts inserted. Mortality rates were 4%, 10%, 18%, and 40%, respectively, for Grade 1, 2, 3, and 4 IVH during initial hospitalization. Length of stay has been trending upward for both groups of IVH (49 days in 2000, 56 days in 2010) and PHH (59 days in 2000, 70 days in 2010). The average hospital cost per patient (adjusted for inflation) has also increased, from $201,578 to $353,554 (for IVH) and $260,077 to $495,697 (for PHH) over 11 years. CONCLUSIONS The number of neonates admitted with IVH has increased despite a decrease in the number of preterm births. Rates of hydrocephalus and mortality correlated closely with IVH grade. The incidence of hydrocephalus in preterm infants with IVH remained stable between 8% and 10%. Over an 11-year period, there was a progressive increase in hospital cost and length of stay for preterm neonates with IVH and PHH that may be explained by a concurrent increase in the proportion of patients with congenital cardiac anomalies.

Surgical management of hydrocephalus secondary to intraventricular hemorrhage in the preterm infant

OBJECT Posthemorrhagic hydrocephalus (PHH) in the preterm infant remains a major neurological complication of prematurity. The authors first described insertion of a specially designed low-profile subcutaneous ventricular catheter reservoir for temporary management of hydrocephalus in 1983. This report presents the follow-up experience with the surgical management of PHH in this population and describes outcomes both in infants who were stable for permanent shunt insertion and those initially temporized with a ventricular reservoir (VR) prior to permanent ventriculoperitoneal (VP)/ventriculoatrial (VA) shunt placement. METHODS A retrospective review was undertaken of the medical records of all premature infants surgically treated for posthemorrhagic hydrocephalus (PHH) between 1997 and 2012 at Children's Hospital Los Angeles. RESULTS Over 14 years, 91 preterm infants with PHH were identified. Fifty neonates received temporizing measures via a VR that was serially tapped for varying time periods. For the remaining 41 premature infants, VP/VA shunt placement was the first procedure. Patients with a temporizing measure as their initial procedure had undergone CSF diversion significantly earlier in life than those who had permanent shunting as the initial procedure (29 vs 56 days after birth, p < 0.01). Of the infants with a VR as their initial procedure, 5/50 (10%) did not undergo subsequent VP/VA shunt placement. The number of shunt revisions and the rates of loculated hydrocephalus and shunt infection did not statistically differ between the 2 groups. CONCLUSIONS Patients with initial VR insertion as a temporizing measure received a CSF diversion procedure significantly earlier than those who received a permanent shunt as their initial procedure. Otherwise, the outcomes with regard to shunt revisions, loculated hydrocephalus, and shunt infection were not different for the 2 groups.

Comparison of the use of ventricular access devices and ventriculosubgaleal shunts in posthaemorrhagic hydrocephalus: systematic review and meta-analysis

INTRODUCTION

Ventricular access devices (VAD) and ventriculosubgaleal shunts (VSGS) are currently both used as temporising devices to affect CSF drainage in neonatal posthaemorrhagic hydrocephalus (PHH), without clear evidence of superiority of either procedure. In this systematic review and meta-analysis, we compared the VSGS and VAD regarding complication rates, ventriculoperitoneal shunt conversion and infection rates, and mortality and long-term disability.

METHODS

The review was registered with the PROSPERO international prospective register of systematic reviews (registration number CRD42015019750) and was conducted in accordance with PRISMA guidelines.

RESULTS AND CONCLUSIONS

The literature search of five databases identified 338 publications, of which 5 met the inclusion criteria. All were retrospective cohort studies (evidence class 3b and 4). A significantly lower proportion of patients with a VSGS required CSF tapping compared to patients with a VAD (log OR -4.43, 95% CI -6.14 to -2.72). No other significant differences between the VAD and VSGS were identified in their rates of infection (log OR 0.03, 95% CI -0.77 to 0.84), obstruction (log OR 1.25, 95% CI -0.21 to 2.71), ventriculoperitoneal shunt dependence (log OR -0.06, 95% CI -0.93 to 0.82), subsequent shunt infection (log OR 0.23, 95% CI -0.61 to 1.06), mortality (log OR 0.37, 95% CI -0.95 to 1.70) or long-term disability (p = 0.9). In all studies, there was a lack of standardised criteria, variations between surgeons in heterogeneous cohorts of limited sample size and a lack of neurodevelopmental follow-up. This affirms the importance of an ongoing multicentre, prospective pilot study comparing these two temporising procedures to enable a more robust comparison.

Shunt revision requirements after posthemorrhagic hydrocephalus of prematurity: insight into the time course of shunt dependency

PURPOSE

Intraventricular hemorrhage (IVH) is a common affliction of preterm infants and often results in posthemorrhagic hydrocephalus (PHH). These patients typically eventually require permanent CSF diversion and are presumed to be indefinitely shunt-dependent. To date, however, there has been no study of long-term shunt revision requirements in patients with PHH.

METHODS

We analyzed retrospectively collected data for 89 preterm patients diagnosed with grades III and IV IVH and PHH at our institution from 1998 to 2011.

RESULTS

Sixty-nine out of 89 patients (77.5%) underwent ventriculoperitoneal (VP) shunt placement, and 33 (47.8%) required at least one shunt revision and 18 (26.1%) required multiple revisions. The mean ± standard deviation follow-up time for shunted patients was 5.0 ± 3.3 years. The majority of early failures were due to proximal catheter malfunction, while later failures were mostly due to distal catheter problems. There was a significant difference in the number of patients requiring revisions in the first 3 years following initial VP shunt insertion compared after 3 years, with 28 revisions versus 10 (p < 0.004). In 8 out of 10 patients who underwent shunt revisions after 3 years, evidence of obstructive hydrocephalus was found on imaging either in the form of an isolated fourth ventricular cyst or aqueductal stenosis.

CONCLUSIONS

Our results suggest that in a distinct subset of patients with PHH, obstructive hydrocephalus may develop, resulting in long-term dependence on CSF diversion. Further study on the factors associated with long-term shunt dependence and revision requirements within the PHH group is warranted.