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.

The Top 100 Most Cited Journal Articles in Pediatric Neurosurgery.

With the many papers published in the field of pediatric neurosurgery, it is often difficult to recognize those that have the most impact on future papers, i.e., citable papers. However, citation analysis allows one to better understand which papers are impacting the field the most. Therefore, the current study aimed to evaluate this literature. The Journal Citation Report database was searched for publications with the words "pediatric neurosurgery" or "pediatric neuro" in the title. Using the Web of Science Core Collection, the top 100 journal articles in pediatric neurosurgery from the selected journals were identified and citation analysis was used to identify the most impactful articles. A search was performed on Web of Science Core Collection by searching for each journal under "Publication Name" and using the Boolean "OR" function to separate fields. The results were ordered by the "Times Cited" category, which provided a list of all the articles from the eight journals appearing in the most cited order. The timeline used was from 1976 to 2021. The top 100 most cited articles were extracted from this list for analysis. The following variables were collected from each scientific article: publication journal, impact factor of journal, title, number of citations, year and month of publication, and type of article. Eight journals were identified on the basis of our search criteria and the articles were sorted by most cited; 1609 pediatric neurosurgery journal articles were screened to select the 100 most cited since 1976. This compilation could serve to help clinicians and researchers to familiarize themselves with the journal articles included in terms of study type, study field, journal of publication, and recurring authors.

Surgically treatable adult epilepsy: a changing patient population. Experience from a level 4 epilepsy center.

OBJECTIVE: Invasive monitoring has long been utilized in the evaluation of patients for epilepsy surgery, providing localizing information to guide resection. Stereoelectroencephalography (SEEG) was introduced at the authors' level 4 epilepsy surgery program in 2013, with responsive neurostimulation (RNS) becoming available the following year. The authors sought to characterize patient demographics and epilepsy-related variables before and after SEEG introduction to understand whether differences emerged in their patient population. This information will be useful in understanding how SEEG, possibly in conjunction with RNS availability, may have changed practice patterns over time. METHODS: This is a retrospective cohort study of consecutive patients who underwent surgery for epilepsy from 2006 to 2018, comprising 7 years before and 5 years after the introduction of SEEG. The authors performed univariate analyses of patient characteristics and outcomes and used generalized estimating equations logistic regression for predictive analysis. RESULTS: A total of 178 patients were analyzed, with 109 patients in the pre-SEEG cohort and 69 patients in the post-SEEG cohort. In the post-SEEG cohort, more patients underwent invasive monitoring for suspected bilateral seizure onsets (40.6% vs 22.0%, p = 0.01) and extratemporal seizure onsets (68.1% vs 8.3%, p < 0.0001). The post-SEEG cohort had a higher proportion of patients with seizures arising from eloquent cortex (14.5% vs 0.9%, p < 0.001). Twelve patients underwent RNS insertion in the post-SEEG group versus none in the pre-SEEG group. Fewer patients underwent resection in the post-SEEG group (55.1% vs 96.3%, p < 0.0001), but there was no significant difference in rates of seizure freedom between cohorts for those patients having undergone a follow-up resection (53.1% vs 59.8%, p = 0.44). CONCLUSIONS: These findings demonstrate that more patients with suspected bilateral, eloquent, or extratemporal epilepsy underwent invasive monitoring after adoption of SEEG. This shift occurred coincident with the adoption of RNS, both of which likely contributed to increased patient complexity. The authors conclude that their practice now considers invasive monitoring for patients who likely would not previously have been candidates for surgical investigation and subsequent intervention.

Postoperative day 1 versus postoperative day 5 morning cortisol for predicting an intact hypothalamic-pituitary axis: A cohort analysis.

BACKGROUND: A reliable standard for evaluating postoperative hypothalamic-pituitary-axis (HPA) function following transsphenoidal pituitary surgery (TSS) could reduce hospital stays and unnecessary prolonged steroid therapy. We retrospectively examined the predictive role of morning cortisol levels on long-term HPA function to develop an institutional protocol. Here, we report the results of this analysis, which is the first to report the predictive strength of multiple variables (i.e., timing of measurement and values of serum cortisol cutoffs) within the same cohort. METHODS: A retrospective chart review was performed in 183 patients at a single institution from 2007 to 2012. 67 patients met inclusion criteria. The predictive value of postoperative day (POD) 1 and POD 5 morning cortisol for HPA function as determined by 1 ug cosyntropin stimulation test was evaluated using standard confusion matrix calculations and receiver-operator control curve analysis. RESULTS: In our cohort, an early POD 5 serum morning cortisol ≥15 ug/dl predicted an intact HPA axis with 100% specificity, 51% sensitivity, and a positive predictive value (PPV) of 100%. A POD 1 serum cortisol ≥25 ug/dl was needed to achieve a specificity of 100% and PPV of 100% to predict an intact HPA axis with a sensitivity of 30%. A POD 1 serum cortisol ≥18 ug/dl predicted an intact HPA axis with 33.3% specificity, PPV of 90.9%, and a sensitivity of 51.3%. CONCLUSION: A POD 5 morning cortisol level ≥15 ug/dl is an excellent predictor of normal postoperative HPA function in patients undergoing TSS for pituitary adenoma.

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.

Association between preoperative activity level and functional outcome at 12 months following surgical decompression for lumbar spinal stenosis.

OBJECTIVE: This study defines the association of preoperative physical activity level with functional outcomes at 3 and 12 months following surgical decompression for lumbar spinal stenosis. METHODS: Data were collected as a prospective observational registry at a single institution from 2012 through 2015, and then analyzed with a retrospective cohort design. Patients who were able to participate in activities outside the home preoperatively were compared to patients who did not participate in such activities, with respect to 3-month and 12-month functional outcomes postintervention, adjusted for relevant confounders. RESULTS: Ninety-nine patients were included. At baseline, sedentary/inactive patients (n = 55) reported greater back pain, lower quality of life, and higher disability than similarly treated patients who were active preoperatively. Both cohorts experienced significant improvement from baseline in back pain, leg pain, disability, and quality of life at both 3 and 12 months after lumbar decompression surgery. At 3 months postintervention, sedentary/inactive patients reported more leg pain and worse disability than patients who performed activities outside the home preoperatively. However, at 12 months postintervention, there were no statistically significant differences between the two cohorts in back pain, leg pain, quality of life, or disability. Multivariate analysis revealed that sedentary/inactive patients had improved disability and higher quality of life after surgery compared to baseline. Active patients experienced greater overall improvement in disability compared to inactive patients. CONCLUSIONS: Sedentary/inactive patients have a more protracted recovery after lumbar decompression surgery for spinal stenosis, but at 12 months postintervention can expect to reach similar long-term outcomes as patients who are active/perform activities outside the home preoperatively.

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.

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.

Obese (Body Mass Index >30) Patients Have Greater Functional Improvement and Reach Equivalent Outcomes at 12 Months Following Decompression Surgery for Symptomatic Lumbar Stenosis.

OBJECTIVE: To evaluate effect of obesity on 12-month functional outcomes after surgery for lumbar stenosis in adult patients. METHODS: Data were collected on patients treated with lumbar laminectomy for symptomatic lumbar spinal stenosis as part of an observational registry and analyzed using a retrospective cohort study design. Patients with body mass index (BMI) >30 were compared with patients with BMI <30 with respect to baseline, 3-month, and 12-month functional status, adjusted for potential confounders. RESULTS: There were 101 patients. At baseline, patients with BMI >30 had significantly more back pain (P < 0.001), more leg pain (P < 0.001), lower EuroQol 5 dimensions questionnaire (EQ-5D) scores (P < 0.001), and higher Oswestry Disability Index (ODI) scores (P < 0.001). Both low- and high-BMI groups had significant improvement in back pain, leg pain, EQ-5D scores, and ODI scores after decompression (all P < 0.001). At 3 months postoperatively, high-BMI patients continued to report greater leg pain (P = 0.063) and higher ODI score (P = 0.064) relative to low-BMI patients. By 12 months, there was no difference between low- and high-BMI patients in back pain (P = 0.929), leg pain (P = 0.638), EQ-5D score (P = 0.733), or ODI score (P = 0.214). CONCLUSIONS: The difference between low- and high-BMI patients trended toward significance for leg pain and ODI score at 3 months, but this difference disappeared by 12 months. This suggests that obese patients with symptomatic lumbar spinal stenosis may require longer to recover after decompression but can expect to reach equivalent outcomes of similarly treated patients with BMI <30.

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.