The prevalence of shunt-treated hydrocephalus: a mathematical model

Surgical intervention for hydrocephalus in infancy; etiology, age and treatment data in a Dutch cohort

PURPOSE

To gain insight into the patient characteristics of surgically treated hydrocephalus in the Netherlands, we report the first data from the Dutch Quality Registry NeuroSurgery (QNRS) database for infants with hydrocephalus requiring surgical intervention.

METHODS

We used the prospectively gathered database concerning infants ≤ 2 years of age surgically treated for hydrocephalus. We report data from start of registry, concerning etiology, age, and treatment of patients registered. We compared data with the Hydrocephalus Clinical Research Network (HCRN), a multicenter network of pediatric neurosurgical institutions in North America.

RESULTS

A total of 359 operated infants was registered in the period from 2010 to 2017. A drop in patients registered was seen in 2015, possibly due to revisions of the database. Most infants were operated on between 1 and 6 months of age. Cause of hydrocephalus was predominantly intracranial hemorrhage, followed by congenital causes. The proportion of infants with aqueduct stenosis and myelomeningocele as cause of hydrocephalus stayed relatively stable during this period of registration. Initial shunting was performed in 40% and reservoir/ETV as initial treatment was done in 60%. In both groups, 50% needed revision surgery.

CONCLUSIONS

The first data concerning surgically treated pediatric hydrocephalus from a prospectively collected Dutch register are presented, showing similar results when comparing to the HCRN database.

How to Reduce Head CT Orders in Children with Hydrocephalus Using the Lean Six Sigma Methodology: Experience at a Major Quaternary Care Academic Children's Center

BACKGROUND AND PURPOSE

Lean Six Sigma methodology is increasingly used to drive improvement in patient safety, quality of care, and cost-effectiveness throughout the US health care delivery system. To demonstrate our value as specialists, radiologists can combine lean methodologies along with imaging expertise to optimize imaging elements-of-care pathways. In this article, we describe a Lean Six Sigma project with the goal of reducing the relative use of pediatric head CTs in our population of patients with hydrocephalus by 50% within 6 months.

MATERIALS AND METHODS

We applied a Lean Six Sigma methodology using a multidisciplinary team at a quaternary care academic children's center. The existing baseline imaging practice for hydrocephalus was outlined in a Kaizen session, and potential interventions were discussed. An improved radiation-free workflow with ultrafast MR imaging was created. Baseline data were collected for 3 months by using the departmental radiology information system. Data collection continued postintervention and during the control phase (each for 3 months). The percentage of neuroimaging per technique (head CT, head ultrasound, ultrafast brain MR imaging, and routine brain MR imaging) was recorded during each phase.

RESULTS

The improved workflow resulted in a 75% relative reduction in the percentage of hydrocephalus imaging performed by CT between the pre- and postintervention/control phases (Z-test, P = .0001).

CONCLUSIONS

Our lean interventions in the pediatric hydrocephalus care pathway resulted in a significant reduction in head CT orders and increased use of ultrafast brain MR imaging.

Emergency Department Use of Computed Tomography for Children with Ventricular Shunts

OBJECTIVES

To quantify rates and variation in emergency department (ED) cranial computed tomography (CT) utilization in children with ventricular shunts, estimate radiation exposure, and evaluate the association between CT utilization and shunt revision.

STUDY DESIGN

Retrospective longitudinal cohort study of ED visits from 2003-2013 in children 0-18 years old with initial shunt placement in 2003. Data were examined from 31 hospitals in the Pediatric Health Information System. Main outcomes were cranial CT performed during an ED visit, estimated cumulative effective radiation dose, and shunt revision within 7 days. Multivariable regression modeled the relationship between patient- and hospital-level covariates and CT utilization.

RESULTS

The 1319 children with initial shunt placed in 2003 experienced 6636 ED visits during the subsequent decade. A cranial CT was obtained in 49.4% of all ED visits; 19.9% of ED visits with CT were associated with a shunt revision. Approximately 6% of patients received ≥10 CTs, accounting for 37.2% of all ED visits with a CT. The mean number of CTs per patient varied nearly 20-fold across hospitals; the individual hospital accounted for the most variation in CT utilization. The median (IQR) cumulative effective radiation dose was 7.2 millisieverts (3.6-14.0) overall, and 33.4 millisieverts (27.2-43.8) among patients receiving ≥10 CTs.

CONCLUSIONS

A CT scan was obtained in half of ED visits for children with a ventricular shunt, with wide variability in utilization by hospitals. Strategies are needed to identify children at risk of shunt malfunction to reduce variability in CT utilization and radiation exposure in the ED.

Test characteristics of quick brain MRI for shunt evaluation in children: an alternative modality to avoid radiation

OBJECT

Quick brain magnetic resonance imaging (QB-MRI) is a rapid, radiation-free technique to detect life-threatening CSF shunt malfunction. QB-MRI has not been widely studied or adopted. The primary objective of this study was to evaluate the test characteristics of QB-MRI for detecting shunt malfunction. Test characteristics of brain computed tomography (CT) and QB-MRI were then compared. Secondary objectives included comparison of time to study completion and use of sedatives for both modalities, as well as comparison of time to study completion for QB-MRI before and after implementation of a Pediatric Emergency Department (PED) shunt clinical pathway.

METHODS

A retrospective chart review was performed at 2 tertiary care hospital PEDs. The authors reviewed the charts of children who underwent QB-MRI or CT for suspected shunt malfunction between July 2008 and June 2012. They also reviewed the patients' neuroradiology reports and classified ventricular size as positive (enlarged) or negative (normal, smaller, or unchanged). Shunt malfunction was defined by surgical revision within 30 days.

RESULTS

Nine hundred ninety-seven PED visits (involving 724 QB-MRIs and 273 CTs) were included. Surgical revision was performed in 235 cases (23.6%). For QB-MRI, sensitivity was 58.5% (95% CI 51.1%-65.6%) and specificity was 93.3% (90.8%-95.3%). For CT, sensitivity was 53.2% (95% CI 38.1%-67.9%) and specificity was 95.6% (92%-97.9%). The mean time to completion of QB-MRI was 115 minutes versus 83 minutes for CT (difference 32 minutes, 95% CI, 22-42 minutes, p < 0.001). The mean time from presentation to completion of QB-MRI prior to application of the CSF shunt pathway was 132 minutes versus 112 minutes after application of the CSF shunt pathway (difference 20 minutes, 95% CI 5-35 minutes, p = 0.01). Anxiolytic medications were used in 3.7% of CT studies and 4.4% of QB-MRI studies (p = 0.74).

CONCLUSIONS

QB-MRI and CT have similar test characteristics for detecting CSF shunt malfunction in children and similar requirements for sedation. The longer interval from order placement to imaging completion for QB-MRI is arguably justified by reduction of radiation exposure in this population subject to frequent brain imaging.

Nonprogrammable and programmable cerebrospinal fluid shunt valves: a 5-year study

OBJECT

Programmable valves (PVs) for shunting CSF have increasingly replaced nonprogrammable valves (NPVs). There have been only a few longer-term studies (≥ 5 years) conducted that have compared the effectiveness of NPVs with that of PVs for children with hydrocephalus, and only 1 study has reported NPVs as being favorable over PVs. The objective of this retrospective study was to compare the long-term survival of these 2 types of shunt valves.

METHODS

The authors collected data for all patients who underwent CSF shunt insertion or revision between January 1, 2000, and December 31, 2008. Patients underwent follow-up for a minimum of 2 years postoperatively. Statistical analyses were done using chi-square, Kaplan-Meier survival curve, and multivariate analyses.

RESULTS

A total of 616 valves were implanted, of which 313 were PVs and 303 were NPVs. Of these, 253 were original shunt implantations and 363 were revisions. The proportion of 5-year survival for NPVs (45.8%) was significantly higher than that for PVs (19.8%) (p = 0.0005, log-rank). The NPVs that survived longer than 6 months also survived through the 5th year better than the PVs (p = 0.0001).

CONCLUSIONS

The authors' data suggest that NPVs survive longer than PVs in children, but there is a need for prospective, case-control studies to confirm these data.