✓ Selective dorsal rhizotomy is a well-established surgical procedure for improving lower-extremity spasticity in children with cerebral palsy. The standard technique requires an L1–S1 laminectomy or laminoplasty for visualization of all dorsal nerve roots exiting at their respective foramina. The authors describe a rhizotomy procedure that requires a single-level laminectomy at the level of the conus, with the advantages of decreased operating time and postoperative pain as well as a minimal risk of progressive lumbar instability. This procedure is both effective and well tolerated in appropriately selected children and adults, and has had one cerebrospinal fluid lead requiring operative repair in more than 1500 patients treated at the authors' institution since 1991.
Tae Sung Park and James M. Johnston
Brandon A. Sherrod, James M. Johnston and Brandon G. Rocque
Hospital readmission rate is increasingly used as a quality outcome measure after surgery. The purpose of this study was to establish, using a national database, the baseline readmission rates and risk factors for patient readmission after pediatric neurosurgical procedures.
The American College of Surgeons National Surgical Quality Improvement Program–Pediatric database was queried for pediatric patients treated by a neurosurgeon between 2012 and 2013. Procedures were categorized by current procedural terminology (CPT) code. Patient demographics, comorbidities, preoperative laboratory values, operative variables, and postoperative complications were analyzed via univariate and multivariate techniques to find associations with unplanned readmissions within 30 days of the primary procedure.
A total of 9799 cases met the inclusion criteria, 1098 (11.2%) of which had an unplanned readmission within 30 days. Readmission occurred 14.0 ± 7.7 days postoperatively (mean ± standard deviation). The 4 procedures with the highest unplanned readmission rates were CSF shunt revision (17.3%; CPT codes 62225 and 62230), repair of myelomeningocele > 5 cm in diameter (15.4%), CSF shunt creation (14.1%), and craniectomy for infratentorial tumor excision (13.9%). The lowest unplanned readmission rates were for spine (6.5%), craniotomy for craniosynostosis (2.1%), and skin lesion (1.0%) procedures. On multivariate regression analysis, the odds of readmission were greatest in patients experiencing postoperative surgical site infection (SSI; deep, organ/space, superficial SSI, and wound disruption: OR > 12 and p < 0.001 for each). Postoperative pneumonia (OR 4.294, p < 0.001), urinary tract infection (OR 4.262, p < 0.001), and sepsis (OR 2.616, p = 0.006) also independently increased the readmission risk. Independent patient risk factors for unplanned readmission included Native American race (OR 2.363, p = 0.019), steroid use > 10 days (OR 1.411, p = 0.010), oxygen supplementation (OR 1.645, p = 0.010), nutritional support (OR 1.403, p = 0.009), seizure disorder (OR 1.250, p = 0.021), and longer operative time (per hour increase, OR 1.059, p = 0.029).
This study may aid in identifying patients at risk for unplanned readmission following pediatric neurosurgery, potentially helping to focus efforts at lowering readmission rates, minimizing patient risk, and lowering costs for health care systems.
Albert N. Martins, James S. Johnston, James M. Henry, Thomas J. Stoffel and Giovanni Di Chiro
✓ The cases of six patients are presented to delineate the clinical profile of delayed radiation necrosis of the brain. In five the diagnosis was verified histologically. Symptoms most often begin 9 months to 2 years after radiotherapy. Progressive visual impairment and dementia are common following perisellar irradiation, while hemispheric signs predominate following irradiation of the cerebrum. Cerebrospinal fluid protein may be elevated. Focal delta slowing is usually present on electroencephalography. The necrotic brain may appear on radionuclide brain scan as an area of abnormal uptake and also act as an avascular space-occupying lesion. With computerized tomography, radiation necrosis appears as an intracerebral area with diminished absorption coefficient that is often enhanced with intravenous contrast medium. The syndrome may be sufficiently characteristic to eliminate the need for surgical exploration and biopsy in some cases. Cumulative experience suggests that the risk-to-benefit ratio of radiotherapy becomes increasingly unfavorable for most patients with benign intracranial neoplasms when the standard brain tumor dose of 5000 to 7000 rads is fractionated at greater than 200 rads per day.
Daxa M. Patel, R. Shane Tubbs, Gigi Pate, James M. Johnston Jr. and Jeffrey P. Blount
Surveillance imaging of the cerebral ventricles can be valuable in following up children with shunt-treated hydrocephalus. There also, however, has been recent increased awareness and concern over the potential risk associated with imaging-related radiation exposure in children. Magnetic resonance imaging represents an imaging alternative that does not use ionizing radiation; however, its practical utility has been limited due to the near-uniform requirement for sedation or general anesthesia in children. Magnetic resonance imaging without sedation is often futile because of the movement artifact produced by the nonsedated pediatric patient. Some studies have demonstrated the feasibility of using fast-sequence MRI (fsMRI), but the reported experiences are limited. The authors have incorporated fsMRI into their routine shunt surveillance imaging paradigms and report here a 5-year experience with this modality.
The authors initially started using fsMRI for routine surveillance in a single clinic in 2008 and have gradually increased their institutional utilization of this modality as experience has accumulated and protocols have been refined. Imaging sequences obtained for each child include an axial T2-weighted half-Fourier acquisition single-shot turbo spin-echo (HASTE), coronal T2-weighted HASTE, and sagittal T2-weighted HASTE images. The authors conducted a retrospective chart and imaging review. They rated each fsMR image according to 5 visibility parameters: 1) ventricle size, 2) ventricle configuration, 3) presence or absence of transependymal flow, 4) presence or absence of motion artifact, and 5) visualization of the ventricular catheter. Each parameter was graded as 1 (present) or 0 (absent). Thus, the maximum value assigned to each scan could be 5 and the minimum value assigned to each scan could be 0. Interrater reliability between pairs of observers was calculated using the Kendall's tau-b and intraclass coefficients.
Two hundred patients underwent fsMRI. No child required sedation. The average duration of examinations was approximately 3.37 minutes, and mean age of the patients was 5.7 years. Clinically useful images were attained in all cases. Overall quality of the fsMRI studies based on the 5 different visibility parameters showed that 169 images (84.5%) included 4 or 5 parameters (score ≥ 4) and had statistically significant excellent quality. The Kendall's tau-b for the overall fsMRI ratings was 0.82 (p = 0.002) and the intraclass coefficient was 0.87 (p < 0.0001).
In the present cohort of 200 patients, fsMRI studies were shown to have an excellent overall quality and a statistically significant high degree of interrater reliability. Consequently, the authors propose that fsMRI is a sufficiently effective modality that eliminates the need for sedation and the use of ionizing radiation and that it should supplant CT for routine surveillance imaging in hydrocephalic patients.
Jonathan Pindrik, Brandon G. Rocque, Anastasia A. Arynchyna, James M. Johnston and Curtis J. Rozzelle
Endoscopic third ventriculostomy (ETV) with choroid plexus (CP) cauterization (CPC) represents a viable treatment option for congenital hydrocephalus in infants younger than 2 years. Imaging studies complement clinical data in the evaluation of treatment success or failure. The objectives of this study were to investigate novel radiographic markers—cerebrospinal fluid (CSF) turbulence and CP visualization—and their ability to reflect or predict clinical outcomes following ETV/CPC.
Hydrocephalic patients younger than 2 years who were initially treated by ETV/CPC at the senior authors' institution between March 2013 and February 2014 were retrospectively reviewed. Clinical data, as well as the visualization of CSF turbulence and CP on pre- and postoperative fast-sequence MRI, were recorded. Radiographic images were reviewed by a blinded observer based on specific criteria for the visualization of CSF turbulence and CP. Data were collected and analyzed using descriptive statistics, including Fisher's exact test for comparisons. The research team obtained appropriate institutional review board approval for this study, without the need for informed consent.
Among the 32 patients (53% male and 47% female) studied, 18 of 32 (56%) responded favorably to initial or repeat ETV/CPC, with 13 of 32 (41%) patients requiring 1 surgery. Of the 19 (59%) patients whose initial ETV/CPC failed, 8 of 19 (42%) patients underwent repeat ETV/CPC, with 5 of 8 (63%) patients responding favorably. Radiographic CSF turbulence appeared more frequently following ETV/CPC failure than after ETV/CPC success (55% vs 18%, respectively; p = 0.02). The sensitivity and specificity of CSF turbulence as a radiographic marker for ETV/CPC failure were 80% and 58%, respectively. The radiographic depiction of CP disappearance following ETV/CPC from pre- to postoperative imaging occurred in 20 of 30 patients (67%). Among the patients who responded unsuccessfully to ETV/CPC and ultimately required secondary shunt insertion, 71% (10 of 14 patients) demonstrated CP persistence on postoperative imaging. In contrast, 6% (1 of 18) of patients who were treated successfully by ETV/CPC demonstrated the presence of CP on follow-up imaging. This difference reached statistical significance (p = 0.0001). The visualization of CP persistence despite ETV/CPC reflected treatment failure with 91% sensitivity and 81% specificity. The sensitivity of either or both radiographic markers to suggest ETV/CPC failure was 77%, while their specificity (both markers absent, thereby indicating ETV/CPC success) was 81%.
Radiographic markers correlate with clinical outcomes following the treatment of infantile hydrocephalus with ETV/CPC. Specifically, CSF turbulence may indicate ongoing pathological CSF flow dynamics, while CP absence following ETV/CPC may predict shunt independence. Future studies that incorporate prospective review and formal intra- and interobserver reliability estimates may help corroborate the utility of these radiographic markers.
Case report and review of the literature
James M. Johnston, Nilesh A. Vyas, Alex A. Kane, David W. Molter and Matthew D. Smyth
✓Epignathus, a congenital oropharyngeal teratoma, is a rare clinical entity with variable clinical outcomes described in the literature. Even fewer cases of epignathus with intracranial extension have been reported, all with poor outcomes. In this manuscript, the authors present a case of epignathus with intracranial extension, emphasizing clinical presentation, imaging findings, a staged surgical approach, multidisciplinary management, and outcome.
James M. Johnston and Tae Sung Park
Esther B. Dupepe, Betsy Hopson, James M. Johnston, Curtis J. Rozzelle, W. Jerry Oakes, Jeffrey P. Blount and Brandon G. Rocque
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).
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.
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.
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.
Ian G. Dorward, Jeffrey B. Titus, David D. Limbrick, James M. Johnston, Mary E. Bertrand and Matthew D. Smyth
Patients undergoing epilepsy surgery without evidence of a lesion on MR imaging and without a temporal source for seizure onset generally have less favorable outcomes than patients with structural lesions or temporal onset. However, many of these patients are viable candidates for invasive monitoring and subsequent resection or multiple subpial transections (MSTs). The purpose of this study was to evaluate the surgical treatment of pediatric patients with extratemporal, nonlesional epilepsy in order to better understand the clinical and neuropsychological outcomes expected in this patient group.
Forty-three pediatric patients with negative results on MR imaging and lateralized, extratemporal findings on electroencephalography underwent invasive monitoring with grid and/or strip electrodes. Thirty-three subsequently had resection of an epileptogenic focus and/or MSTs.
Outcome was classified as Engel class I or II in 54.5% of the patients who underwent resection/MSTs and Engel class III or IV in 45.5%. Use of MSTs was associated with poor outcome. Neuropsychological evaluation showed significant improvement in immediate auditory attention following surgery and revealed several significant results on subgroup analysis. Complications occurred in 14% of patients (a 7% rate per procedure). Ten patients (23%) underwent invasive monitoring without proceeding to therapeutic surgery because no epileptogenic region was amenable to resection. Neuropsychological outcomes were generally stable.
Patients with extratemporal, nonlesional seizures are viable candidates for invasive monitoring with grid/strip electrodes, and good outcomes can be obtained with resective surgery. The use of MSTs may correlate with worse outcome. This study also provides additional data to assist in counseling patients on the risks of negative invasive monitoring, deficits resulting from resection/MSTs, and possible operative complications.
Michael C. Dewan, Ronnie E. Baticulon, Abbas Rattani, James M. Johnston Jr., Benjamin C. Warf and William Harkness
The presence and capability of existing pediatric neurosurgical care worldwide is unknown. The objective of this study was to solicit the expertise of specialists to quantify the geographic representation of pediatric neurosurgeons, access to specialist care, and equipment and training needs globally.
A mixed-question survey was sent to surgeon members of several international neurosurgical and general pediatric surgical societies via a web-based platform. Respondents answered questions on 5 categories: surgeon demographics and training, hospital and practice details, surgical workforce and access to neurosurgical care, training and equipment needs, and desire for international collaboration. Responses were anonymized and analyzed using Stata software.
A total of 459 surgeons from 76 countries responded. Pediatric neurosurgeons in high-income and upper-middle-income countries underwent formal pediatric training at a greater rate than surgeons in low- and lower-middle-income countries (89.5% vs 54.4%). There are an estimated 2297 pediatric neurosurgeons in practice globally, with 85.6% operating in high-income and upper-middle-income countries. In low- and lower-middle-income countries, roughly 330 pediatric neurosurgeons care for a total child population of 1.2 billion. In low-income countries in Africa, the density of pediatric neurosurgeons is roughly 1 per 30 million children. A higher proportion of patients in low- and lower-middle-income countries must travel > 2 hours to seek emergency neurosurgical care, relative to high-income countries (75.6% vs 33.6%, p < 0.001). Vast basic and essential training and equipment needs exist, particularly low- and lower-middle-income countries within Africa, South America, the Eastern Mediterranean, and South-East Asia. Eighty-nine percent of respondents demonstrated an interest in international collaboration for the purposes of pediatric neurosurgical capacity building.
Wide disparity in the access to pediatric neurosurgical care exists globally. In low- and lower-middle-income countries, wherein there exists the greatest burden of pediatric neurosurgical disease, there is a grossly insufficient presence of capable providers and equipped facilities. Neurosurgeons across income groups and geographic regions share a desire for collaboration and partnership.