Rate of shunt revision as a function of age in patients with shunted hydrocephalus due to myelomeningocele.

OBJECTIVE It is generally accepted that cerebrospinal fluid shunts fail most frequently in the first years of life. The purpose of this study was to describe the risk of shunt failure for a given patient age in a well-defined cohort with shunted hydrocephalus due to myelomeningocele (MMC). METHODS The authors analyzed data from their institutional spina bifida research database including all patients with MMC and shunted hydrocephalus. For the entire population, the number of shunt revisions in each year of life was determined. Then the number of patients at risk for shunt revision during each year of life was calculated, thus enabling them to calculate the rate of shunt revision per patient in each year of life. In this way, the timing of all shunt revision operations for the entire clinic population and the likelihood of having a shunt revision during each year of life were calculated. RESULTS A total of 655 patients were enrolled in the spina bifida research database, 519 of whom had a diagnosis of MMC and whose mean age was 17.48 ± 11.7 years (median 16 years, range 0-63 years). Four hundred seventeen patients had had a CSF shunt for the treatment of hydrocephalus and thus are included in this analysis. There were 94 shunt revisions in the 1st year of life, which represents a rate of 0.23 revisions per patient in that year. The rate of shunt revision per patient-year initially decreased as age increased, except for an increase in revision frequency in the early teen years. Shunt revisions continued to occur as late as 43 years of age. CONCLUSIONS These data substantiate the idea that shunt revision surgeries in patients with MMC are most common in the 1st year of life and decrease thereafter, except for an increase in the early teen years. A persistent risk of shunt failure was observed well into adult life. These findings underscore the importance of routine follow-up of all MMC patients with shunted hydrocephalus and will aid in counseling patients and families.

Etiology- and region-specific characteristics of transependymal cerebrospinal fluid flow.

OBJECTIVE: Transependymal flow (TEF) of CSF, often delineated as T2-weighted hyperintensity adjacent to the lateral ventricles on MRI, is a known imaging finding, usually in the setting of CSF flow disturbances. Specific radiological features of TEF and their relationships with clinical markers of hydrocephalus and underlying disease pathology are not known. Here, the authors describe the radiological features and clinical associations of TEF with implications for CSF circulation in the setting of intracranial pathology. METHODS: After obtaining IRB review and approval, the authors reviewed the radiological records of all patients who underwent intracranial imaging with CT or MRI at St. Louis Children's Hospital, St. Louis, Missouri, between 2008 and 2019 to identify individuals with TEF. Then, under direct review of imaging, TEF pattern, degree, and location and underlying pathology and other radiological and clinical features pertaining to CSF circulation and CSF disturbances were noted. RESULTS: TEF of CSF was identified in 219 patients and was most prevalent in the setting of neoplasms (72%). In 69% of the overall cohort, TEF was seen adjacent to the anterior aspect of the frontal horns and the posterior aspect of the occipital horns of the lateral ventricles, and nearly half of these patients also had TEF dorsal to the third ventricle near the splenium of the corpus callosum. This pattern was independently associated with posterior fossa medulloblastoma when compared with pilocytic astrocytoma (OR 4.75, 95% CI 1.43-18.53, p = 0.0157). Patients with congenital or neonatal-onset hydrocephalus accounted for 13% of patients and were more likely to have TEF circumferentially around the ventricles without the fronto-occipital distribution. Patients who ultimately required permanent CSF diversion surgery were more likely to have the circumferential TEF pattern, a smaller degree of TEF, and a lack of papilledema at the time of CSF diversion surgery. CONCLUSIONS: CSF transmigration across the ependyma is usually restricted to specific periventricular regions and is etiology specific. Certain radiological TEF characteristics are associated with tumor pathology and may reflect impaired or preserved ependymal fluid handling and global CSF circulation. These findings have implications for TEF as a disease-specific marker and in understanding CSF handling within the brain.

What is a Case-Control Study?

Case-control (case-control, case-controlled) studies are beginning to appear more frequently in the neurosurgical literature. They can be more robust, if well designed, than the typical case series or even cohort study to determine or refine treatment algorithms. The purpose of this review is to define and explore the differences between case-control studies and other so-called nonexperimental, quasiexperimental, or observational studies in determining preferred treatments for neurosurgical patients.

Inter-rater reliability of the modified Medical Research Council scale in patients with chronic incomplete spinal cord injury.

OBJECTIVE: The aim of this study was to determine the inter-rater reliability of the modified Medical Research Council (MRC) scale for grading motor function in patients with chronic incomplete spinal cord injury (SCI). METHODS: Two neurosurgical residents and 2 faculty members performed motor examinations in 6 chronic incomplete SCI patients for a total of 156 muscle groups. Examinations were performed using the modified MRC grading scale during routine clinic visits for each patient. Informed consent was obtained prior to enrollment. Patients with American Spinal Injury Association (ASIA) Impairment Scale grade A (ASIA A) injuries were excluded. Inter-rater reliability coefficients were calculated using Kendall's coefficient of concordance (W) and intraclass correlation coefficients (ICCs). RESULTS: Sixty-four percent of the tested variables demonstrated extremely strong (W 0.71-0.9) or strong (0.51-0.7) inter-rater reliability using Kendall's coefficient of concordance and an ICC corresponding to excellent (ICC > 0.75) or fair to good (ICC 0.4-0.75) inter-rater reliability. An additional 7% showed poor inter-rater reliability (ICC < 0.4). The remaining variables tested did not reach statistical significance. CONCLUSIONS: The inter-rater reliability of the modified MRC scale was found to be high in the majority of tested variables, but the results suggest that discrepancy among trained observers does exist. Reliability was greatest in the lower-extremity muscle groups and least in the upper-extremity muscle groups in patients with chronic incomplete SCI.

What Isn't a Case-Control Study?

BACKGROUND: Confusion exists among neurosurgeons when choosing and implementing an appropriate study design and statistical methods when conducting research. We noticed particular difficulty with mislabeled and inappropriate case-control studies in the neurosurgical literature. OBJECTIVE: To quantify and to rigorously review this issue for appropriateness in publication and to establish quality of the manuscripts using a rigorous technique. METHODS: Following a literature search, pairs drawn from 5 independent reviewers evaluated a complete sample of 125 manuscripts claiming to be case-control studies with respect to basic case-control criteria. Seventy-five papers were then subjected to a more rigorous appraisal for quality using the SIGN Methodology Checklist for case-control studies. RESULTS: Fifty publications were rejected based on basic criteria used to identify case-control design. Of the 75 subjected to quality analysis, 46 were felt to be acceptable for publication. Only 11 papers (9%) achieved the designation of high quality. Of the original 125 papers evaluated, 79 (63%) were inappropriately labeled case-control studies. CONCLUSION: Mislabeling and use of inappropriate study design are common in the neurosurgical literature. Manuscripts should be evaluated rigorously by reviewers and readers, and neurosurgical training programs should include instruction on choice of appropriate study design and critical appraisal of the literature.

Intracranial Hemorrhage in Patients with a Left Ventricular Assist Device.

BACKGROUND: There is a dearth of literature regarding management and outcomes of patients with a left ventricular assist device (LVAD) for advanced heart failure who develop intracranial hemorrhage (ICH). We conducted a case series from 2 centers highlighting patient outcomes and prognostic factors to help clinicians better understand and care for these high-risk patients. METHODS: A case series from 2 large-volume institutions (defined as large by the Nationwide Inpatient Sample hospital size, i.e., >500 beds both with Departments of Neurosurgery and Advanced Heart Failure-Cardiology) was conducted to clarify the prognosis of patients with an LVAD and ICH. We included patients who were being treated with an LVAD who developed ICH. Patient-specific demographics and data regarding heart failure and intracranial hemorrhage characteristics were collected and analyzed to determine which factors contributed to overall survival. RESULTS: We analyzed 59 unique ICHs in patients being treated with an LVAD for heart failure. Initial Glasgow Coma Scale score, presence of midline shift, and ICH size were factors found to be predictive of mortality. One institution had a sicker patient population including patients with ICH with lower Glasgow Coma Scale score, presence of midline shift, and greater hemorrhage size, which led to overall higher mortality compared with the second institution. CONCLUSIONS: Patients being treated with an LVAD who develop ICH have poor outcomes. Predictive factors for same-admission mortality are lower initial Glasgow Coma Scale score, presence of midline shift, and greater ICH volume.

Association between payer status and patient-reported outcomes in adult patients with lumbar spinal stenosis treated with decompression surgery.

OBJECTIVE: Insurance disparities can have relevant effects on outcomes after elective lumbar spinal surgery. The aim of this study was to evaluate the association between private/public payer status and patient-reported outcomes in adult patients who underwent decompression surgery for lumbar spinal stenosis. METHODS: A sample of 100 patients who underwent surgery for lumbar spinal stenosis from 2012 to 2014 was evaluated as part of the prospectively collected Quality Outcomes Database at a single institution. Outcome measures were evaluated at 3 months and 12 months, analyzed in regard to payer status (private insurance vs Medicare/Veterans Affairs insurance), and adjusted for potential confounders. RESULTS: At baseline, patients had similar visual analog scale back and leg pain, Oswestry Disability Index, and EQ-5D scores. At 3 months postintervention, patients with government-funded insurance reported significantly worse quality of life (mean difference 0.11, p < 0.001) and more leg pain (mean difference 1.26, p = 0.05). At 12 months, patients with government-funded insurance reported significantly worse quality of life (mean difference 0.14, p < 0.001). There were no significant differences at 3 months or 12 months between groups for back pain (p = 0.14 and 0.43) or disability (p = 0.19 and 0.15). Across time points, patients in both groups showed improvement at 3 months and 12 months in all 4 functional outcomes compared with baseline (p < 0.001). CONCLUSIONS: Both private and public insurance patients had significant improvement after elective lumbar spinal surgery. Patients with public insurance had slightly less improvement in quality of life after surgery than those with private insurance but still benefited greatly from surgical intervention, particularly with respect to functional status.

Education level as a prognostic indicator at 12 months following decompression surgery for symptomatic lumbar spinal stenosis.

OBJECTIVEThe goal of this study was to analyze the effect of patient education level on functional outcomes following decompression surgery for symptomatic lumbar spinal stenosis.METHODSPatients with surgically decompressed symptomatic lumbar stenosis were collected in a prospective observational registry at a single institution between 2012 and 2014. Patient education level was compared to surgical outcomes to elucidate any relationships. Outcomes were defined using the Oswestry Disability Index score, back and leg pain visual analog scale (VAS) score, and the EuroQol-5 Dimensions questionnaire score.RESULTSOf 101 patients with symptomatic lumbar spinal stenosis, 27 had no college education and 74 had a college education (i.e., 2-year, 4-year, or postgraduate degree). Preoperatively, patients with no college education had statistically significantly greater back and leg pain VAS scores when compared to patients with a college education. However, there was no statistically significant difference in quality of life or disability between those with no college education and those with a college education. Postoperatively, patients in both cohorts improved in all 4 patient-reported outcomes at 3 and 12 months after treatment for symptomatic lumbar spinal stenosis.CONCLUSIONSDespite their education level, both cohorts showed improvement in their functional outcomes at 3 and 12 months after decompression surgery for symptomatic lumbar spinal stenosis.

Surveillance survey of family history in children with neural tube defects.

OBJECTIVE Although there are known risk factors for the development of neural tube defects (NTDs), little is known regarding the role of family history. The authors' goal in this study is to describe the family history in their population of patients with NTDs. METHODS Surveys were completed for 254 patients who were accompanied by their biological mother during their annual visit to the multidisciplinary Spina Bifida Clinic at Children's of Alabama. An NTD has been diagnosed in all patients who are seen in this clinic (myelomeningocele, lipomeningocele, split cord malformation, and congenital dermal sinus tract). Each mother answered questions regarding known NTD risk factors and their pregnancy, as well as the family history of NTDs, other CNS disorders, and birth defects. RESULTS The overall prevalence of family history of NTDs in children with an NTD was 16.9% (n = 43), of which 3.1% (n = 8) were in first-degree relatives. In patients with myelomeningocele, 17.7% (n = 37) had a positive family history for NTDs, with 3.8% in first-degree relatives. Family history in the paternal lineage for all NTDs was 8.7% versus 10.6% in the maternal lineage. Twenty-two patients (8.7%) had a family history of other congenital CNS disorders. Fifteen (5.9%) had a family history of Down syndrome, 12 (4.7%) had a family history of cerebral palsy, and 13 (5.1%) patients had a family history of clubfoot. Fourteen (5.5%) had a family history of cardiac defect, and 13 (5.1%) had a family history of cleft lip or palate. CONCLUSIONS The family history of NTDs was 16.9% in children with NTD without a difference between maternal and paternal lineage. This high rate of positive family history suggests that genetics and epigenetics may play a larger role in the pathogenesis of NTD in the modern era of widespread folate supplementation.