Automated identification and quality measurement for pediatric convulsive status epilepticus.

OBJECTIVE: Treatment delays for refractory convulsive status epilepticus (RCSE) are associated with worse outcomes. In the United States, treatment for pediatric RCSE is slower than guidelines recommend. To address this gap, the American Academy of Neurology and Child Neurology Society (AAN/CNS) developed a quality measure: the percentage of RCSE patients that receive third-line treatment within 60 minutes. We aimed to develop computable phenotypes for convulsive status epilepticus (CSE) and RCSE to automate calculation of the quality measure. METHODS: From an observational cohort of children presenting to the emergency department for seizures or epilepsy, we identified presentations of RCSE and its precursors: CSE and benzodiazepine-resistant status epilepticus (BRSE). These served as a gold standard for computable phenotype development. Using multivariate analyses, we constructed and evaluated statistical models for case identification. We then evaluated adherence to the AAN/CNS RCSE quality measure. RESULTS: From 664 charts, we identified 56 patients with CSE, 36 with BRSE, and 18 with RCSE. Four predictors were used: International Classification of Diseases (ICD) codes, and receiving first-, second-, or third-line agents shortly after presentation to the emergency department (ED). Combinations of these predictors identified CSE with 84% sensitivity and 81% positive predictive value (PPV), BRSE with 67% sensitivity and 89% PPV, and RCSE with 94% sensitivity and 85% PPV. Median (interquartile range [IQR]) time to treatment for first-line agent was 13 (5-27) minutes for CSE, second-line for BRSE was 24 (9.5-43.5) minutes, and third-line for RCSE was 52 (27-87) minutes. Sixty percent of RCSE patients received a third-line agent within 60 minutes of ED arrival. SIGNIFICANCE: RCSE and its precursors can be identified automatically with high fidelity allowing automated calculation of time to treatment and the RCSE quality measure. This has the potential to facilitate quality improvement work and improve care for RCSE.

Lumbar juxtafacet cyst resection: the facet sparing contralateral minimally invasive surgical approach.

STUDY DESIGN: A retrospective review. OBJECTIVE: To report our approach and results using a contralateral minimally invasive spinal surgical muscle splitting approach that allows visualization of the cyst without extensive removal of the adjacent facet joint. SUMMARY OF BACKGROUND DATA: The use of tubular retractors for spinal surgery can potentially minimize tissue injury. Contralateral approaches may be beneficial in visualizing pathology that is located adjacent or under the facet joint. This approach has not been reported previously. METHODS: Sixteen consecutive patients were treated using this approach using tubular retractors and the operating microscope. A retrospective chart and imaging review was conducted to determine operative and clinical measures. Subsequently, patients were contacted to obtain long-term clinical follow-up. RESULTS: Nine patients had an excellent and 5 had a good outcome, with median follow-up of 18 months, 2 patients were lost due to lack of follow-up. The mean operative time was 105 minutes and in all cases the blood loss was <40 mL. No postoperative instability was noted. CONCLUSIONS: A contralateral approach using a tubular retractor system provides excellent visualization of the facet cyst allowing safe cyst resection and nerve root decompression without compromising the facet joint. Larger case series with longer follow-up are needed to assess stability.

Pediatric Hydrocephalus in Northwest Tanzania: A Descriptive Cross-Sectional Study of Clinical Characteristics and Early Surgical Outcomes from the Bugando Medical Centre.

OBJECTIVES: In this study, we present data from a neurosurgical training program in Tanzania for the treatment of pediatric hydrocephalus. The objectives of the study were to identify the demographics and clinical characteristics of pediatric patients with hydrocephalus who were admitted to Bugando Medical Centre in Mwanza, Tanzania, as well as to describe their surgical treatment and early clinical outcomes. METHODS: This cross-sectional study included 38 pediatric patients. Physical examinations were conducted pre- and postoperatively, and their mothers completed a questionnaire providing demographic and clinical characteristics. RESULTS: There was a slight preponderance of male sex (21/38; 55.3%) with median age at the time of admission of 98.5 days. The majority of patients were surgically treated (33/38; 86.8%). Among those surgically treated, most received a ventriculoperitoneal shunt (23/33; 69.7%), whereas 7 were treated with an endoscopic third ventriculostomy (7/33; 21.2%). At the time of admission, the majority of patients (86%) had head circumferences that met criteria for macrocephaly. The median time between admission and surgery was 23 days (2-49 days). Overall, 5 patients (13.2%) died, including 2 who did not receive surgical intervention. CONCLUSIONS: We found that in our population, pediatric patients with hydrocephalus often present late for treatment with additional significant delays prior to receiving any surgical intervention. Five patients died, of whom 2 had not undergone surgery. Our study reinforces that targeted investments in clinical services are needed to enable access to care, improve surgical capacity, and alleviate the burden of neurosurgical disease from pediatric hydrocephalus in sub-Saharan Africa.

Upfront molecular targeted therapy for the treatment of BRAF-mutant pediatric high-grade glioma.

BACKGROUND: The prognosis for patients with pediatric high-grade glioma (pHGG) is poor despite aggressive multimodal therapy. Objective responses to targeted therapy with BRAF inhibitors have been reported in some patients with recurrent BRAF-mutant pHGG but are rarely sustained. METHODS: We performed a retrospective, multi-institutional review of patients with BRAF-mutant pHGG treated with off-label BRAF +/- MEK inhibitors as part of their initial therapy. RESULTS: Nineteen patients were identified, with a median age of 11.7 years (range, 2.3-21.4). Histologic diagnoses included HGG (n = 6), glioblastoma (n = 3), anaplastic ganglioglioma (n = 4), diffuse midline glioma (n = 3), high-grade neuroepithelial tumor (n = 1), anaplastic astrocytoma (n = 1), and anaplastic astroblastoma (n = 1). Recurrent concomitant oncogenic alterations included CDKN2A/B loss, H3 K27M, as well as mutations in ATRX, EGFR, and TERT. Eight patients received BRAF inhibitor monotherapy. Eleven patients received combination therapy with BRAF and MEK inhibitors. Most patients tolerated long-term treatment well with no grade 4-5 toxicities. Objective and durable imaging responses were seen in the majority of patients with measurable disease. At a median follow-up of 2.3 years (range, 0.3-6.5), three-year progression-free and overall survival for the cohort were 65% and 82%, respectively, and superior to a historical control cohort of BRAF-mutant pHGG patients treated with conventional therapies. CONCLUSIONS: Upfront targeted therapy for patients with BRAF-mutant pHGG is feasible and effective, with superior clinical outcomes compared to historical data. This promising treatment paradigm is currently being evaluated prospectively in the Children's Oncology Group ACNS1723 clinical trial.

Operative results and learning curve: microscope-assisted tubular microsurgery for 1- and 2-level discectomies and laminectomies.

OBJECT: The authors present their clinical results and the learning curve associated with the use of tubular retractors for 1- and 2-level lumbar microscope-assisted discectomies and laminectomies. METHODS: The study involves a retrospective and prospective analysis of 230 patients who underwent noninstrumented minimally invasive procedures for degenerative lumbar spinal disease between 2004 and 2007. Data on patient demographic characteristics and operative results, including length of stay, blood loss, operative times, and surgical complications were collected. Clinical outcomes were assessed based on pre- and postoperative Visual Analog Scale scores, Oswestry Disability Index values, and the Macnab outcome scale scores. RESULTS: The results showed characteristic differences in blood loss and operating times between 1- and 2-level procedures and between discectomies and laminectomies. A significant learning curve was seen by a decrease in operating time for 1-level discectomies and 2-level laminectomies. Major complications were not observed. CONCLUSIONS: The use of tubular retractors for microsurgical decompression of degenerative spinal disease is a safe and effective treatment modality. As with other techniques, minimally invasive procedures are associated with a significant learning curve. As surgeons become more comfortable with the procedure, its applications can be expanded to include, for example, spinal instrumentation and deformity correction.

Radiographic and Clinical Outcome of Silicate-substituted Calcium Phosphate (Si-CaP) Ceramic Bone Graft in Spinal Fusion Procedures.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate the radiographic and clinical outcome of silicate-substituted calcium phosphate (Si-CaP), utilized as a graft substance in spinal fusion procedures. SUMMARY OF BACKGROUND DATA: Specific properties of Si-CaP provide the graft with negative surface charge that can result in a positive effect on the osteoblast activity and neovascularization of the bone. METHODS: This study included those patients who underwent spinal fusion procedures between 2007 and 2011 in which Si-CaP was used as the only bone graft substance. Fusion was evaluated on follow-up CT scans. Clinical outcome was assessed using Oswestry Disability Index, Neck Disability Index, and the visual analogue scale (VAS) for back, leg, neck, and arm pain. RESULTS: A total of 234 patients (516 spinal fusion levels) were studied. Surgical procedures consisted of 57 transforaminal lumbar interbody fusion, 49 anterior cervical discectomy and fusion, 44 extreme lateral interbody fusion, 30 posterior cervical fusions, 19 thoracic fusion surgeries, 17 axial lumbar interbody fusions, 16 combined anterior and posterior cervical fusions, and 2 anterior lumbar interbody fusion. At a mean radiographic follow-up of 14.2±4.3 months, fusion was found to be present in 82.9% of patients and 86.8% of levels. The highest fusion rate was observed in the cervical region. At the latest clinical follow-up of 21.7±14.2 months, all clinical outcome parameters showed significant improvement. The Oswestry Disability Index improved from 45.6 to 13.3 points, Neck Disability Index from 40.6 to 29.3, VAS back from 6.1 to 3.5, VAS leg from 5.6 to 2.4, VAS neck from 4.7 to 2.7, and VAS arm from 4.1 to 1.7. Of 7 cases with secondary surgical procedure at the index level, the indication for surgery was nonunion in 3 patients. CONCLUSIONS: Si-CaP is an effective bone graft substitute. At the latest follow-up, favorable radiographic and clinical outcome was observed in the majority of patients. LEVEL OF EVIDENCE: Level-III.

The vertebral artery and the cervical pedicle: morphometric analysis of a critical neighborhood.

OBJECT The purpose of this retrospective study was to quantify the anatomical relationship between the vertebral artery (VA), the cervical pedicle, and its surrounding structures, including the incidence of irregularities. Additionally, data delineating a "safe zone," and these data's application during instrumentation with transpedicular cervical screw fixation were considered. The anatomical proximity of the VA to the cervical pedicle prevents spine surgeons from preferring cervical pedicle screws (CPSs) over lateral mass screws at levels C3-6. Accurate placement of CPSs is often difficult to determine, because this definition can vary between 1 and 4 mm of lateral "noncritical" and "critical" pedicle breaches. No previous study in a western population has investigated the VA's proximity to the cervical pedicle, its percentage of occupancy in the transverse foramen (TF), and the incidence of irregular VA pathways. METHODS One hundred twenty-seven consecutive patients who underwent CT angiography of the neck were enrolled in this study. The measurements included the following: medial pedicle border to VA; lateral pedicle border to VA; pedicle diameter (PD); sagittal diameter of the VA; coronal diameter of the VA; sagittal diameter of the TF; and coronal diameter of the TF. The cross-sections of the VA and the TF were measured to determine the occupation ratio of the VA. In addition, a safe zone was defined based on all lateral pedicle border to VA measurements in which the VA was within the TF. The level of entry of the VA into the TF as well as irregularities of the VA and the cervical pedicles were recorded. RESULTS Vertebral artery dominance on the left side was seen in 69.3% of cases. The mean PD increased from 4.9 to 6.5 mm (from C-3 to C-7, respectively). Statistically significantly bigger PDs were seen in males. The mean PD at C-2 was 5.6 mm. Entry of the VA at C-6 was seen in approximately 80% of cases. The TF occupation ratio of the VA was found to be the greatest in C-4 and C-7 (37.1 and 74.2%, respectively). The safe zone increased from C-2 to C-6 (1.1 to 1.7 mm, respectively), but was only 0.65 mm at C-7. In 23.6% of cases, an irregular pathway of the VA or irregular anatomy of a cervical pedicle was seen, with the highest incidence of irregularities found at C-2. CONCLUSIONS Computed tomography angiography is a valuable tool that can help determine the relationships between cervical pedicles and the VA as well as irregular VA pathways. Pedicle diameter, safe zone, and occupational ratio of the VA in the foramen determine the risk associated with instrumentation and should be assessed individually. Based on the authors' measurements, C-4 and C-7 can be considered critical levels for CPS placement. Because of this and the high incidence of irregular VA pathways and different entry points, it may be helpful to review neck CT angiography studies before considering posterior instrumentation procedures in the cervical spine.

Results and risk factors for recurrence following single-level tubular lumbar microdiscectomy.

OBJECT: The use of minimally invasive surgical techniques, including microscope-assisted tubular lumbar microdiscectomy (tLMD), has gained increasing popularity in treating lumbar disc herniations (LDHs). This particular procedure has been shown to be both cost-efficient and effective, resulting in outcomes comparable to those of open surgical procedures. Lumbar disc herniation recurrence necessitating reoperation, however, remains an issue following spinal surgery, with an overall reported incidence of approximately 3-13%. The authors' aim in the present study was to report their experience using tLMD for single-level LDH, hoping to provide further insight into the rate of surgical recurrence and to identify potential risk factors leading to this complication. METHODS: The authors retrospectively reviewed the cases of 217 patients who underwent tLMD for single-level LDH performed identically by 2 surgeons (J.B., R.H.) between 2004 and 2008. Evaluation for LDH recurrence included detailed medical chart review and telephone interview. Recurrent LDH was defined as the return of preoperative signs and symptoms after an interval of postoperative resolution, in conjunction with radiographic demonstration of ipsilateral disc herniation at the same level and pathological confirmation of disc material. A cohort of patients without recurrence was used for comparison to identify possible risk factors for recurrent LDH. RESULTS: Of the 147 patients for whom the authors were able to definitively assess symptomatic recurrence status, 14 patients (9.5%) experienced LDH recurrence following single-level tLMD. The most common level involved was L5-S1 (42.9%) and the mean length of time to recurrence was 12 weeks (range 1.5-52 weeks). Sixty-four percent of the patients were male. In a comparison with patients without recurrence, the authors found that relatively lower body mass index was significantly associated with recurrence (p = 0.005), such that LDH in nonobese patients was more likely to recur. CONCLUSIONS: Recurrence rates following tLMD for LDH compare favorably with those in patients who have undergone open discectomy, lending further support for its effectiveness in treating single-level LDH. Nonobese patients with a relatively lower body mass index, in particular, appear to be at greater risk for recurrence.

Tubular microsurgery for lumbar discectomies and laminectomies in obese patients: operative results and outcome.

STUDY DESIGN: This is a retrospective single-center case study involving 115 obese and nonobese patients who underwent minimally invasive lumbar surgery between 2004 and 2007. OBJECTIVE: The purpose of this study was to evaluate the effect of minimally invasive spinal surgery in obese and nonobese patients by operative results and patient outcomes. SUMMARY OF BACKGROUND DATA: Spinal surgery in obese patients is associated with increased complications, blood loss, and operative times. The potential benefits of minimally invasive lumbar surgery in obese patients are discussed. METHODS: All patients underwent 1-level lumbar microdiscectomy or laminectomy using tubular retractors. Data were collected on patient demographics, comorbidities, smoking habits, operative results, and clinical outcomes, and compared for obese and nonobese patients. Operative results included operative times, blood loss, length of stay, and perioperative complications. Clinical outcomes were assessed by using pre- and postoperative visual analog scale and Macnab outcome criteria at most recent follow-up. RESULTS: In this study, 31% of 115 patients were classified as obese. Obese patients tended to undergo surgery at a younger age. Obesity, comorbidities, and age did not have an impact on patient outcome at a mean follow-up of 15.9 months. No significant differences were seen between obese versus nonobese patients in terms of incision lengths, operative time, blood loss, and complication rates. In obese patients, all parameters and operative results compared favorably to reported historical results of patients undergoing open lumbar surgery. Overall, favorable outcome was seen in 92% and 84% of obese and nonobese lumbar microdiscectomy patients, respectively, and in 75% of laminectomy patients. Postoperative visual analog scale did not show any significant difference. CONCLUSION: This is the first study comparing operative results from tubular microsurgery between obese and nonobese patients. No major differences were detected in outcome, operative and perioperative data including complication rates. With tubular microsurgery, obese patients experienced the same or equally beneficial outcome, compared to nonobese patients, while incision lengths, blood loss, operative times, and length of stay were less when compared to open procedures. Other comorbidities and age had no significant impact on perioperative complications and clinical outcome.

Bioabsorbable instrumentation for single-level cervical degenerative disc disease: a radiological and clinical outcome study.

OBJECT: The authors present the radiological and clinical outcome data obtained in patients who underwent single-level anterior cervical discectomy and fusion (ACDF) for cervical spondylosis and/or disc herniation; bioabsorbable plates were used for instrumentation. The use of metallic plates in ACDF has gained acceptance as a stabilizing part of the procedure to increase fusion rates, but when complications occur with these devices, the overall effectiveness of the procedure is compromised. As a possible solution, bioabsorbable implants for ACDF have been developed. This study investigates the feasibility and radiological and clinical outcomes of the bioabsorbable plates for ACDF. METHODS: The radiological and clinical outcomes of 30 patients were investigated retrospectively. All patients presented with cervical radiculopathy or myelopathy and underwent single-level ACDF in which a bioabsorbable anterior cervical plate and an allograft bone spacer were placed at a level between C-3 and C-7. Radiological outcome was assessed based on the fusion rate, subsidence, and Cobb angle of the surgical level. Clinical outcome was determined by using a visual analog scale, the Neck Disability Index, and the Odom criteria. RESULTS: There were no intraoperative complications, and no hardware failure was observed. No signs or symptoms of adverse tissue reaction caused by the implant were seen. Two reoperations were necessary due to postoperative blood collections. The overall complication rate was 16.7%. After 6 months, radiographic fusion was seen in 92.3% of patients. Subsidence at 11.3 +/- 7.2 months was 3.1 +/- 5.8 mm (an 8.2% change over the immediately postoperative results), and the change in the sagittal curvature was -2.7 +/- 2.7 degrees . The visual analog scale score for neck and arm pain and Neck Disability Index improved significantly after surgery (p < 0.001). Overall at 19.5 months postoperatively, 83% of the patients had favorable outcomes based on the Odom criteria. CONCLUSIONS: Absorbable instrumentation provides better stability than the absence of a plate but graft subsidence and deformity rates may be higher than those associated with metal implants. There were no device-related complications, but adverse late effects cannot be excluded. The fusion rate and outcome are comparable to the results achieved with metallic plates. The authors were satisfied with the use of bioabsorbable plates as a reasonable alternative to metal, avoiding the need for lifelong metallic implants.