Laser interstitial thermal therapy for newly diagnosed and recurrent glioblastoma.

OBJECTIVE Glioblastoma (GBM) is the most common and deadly malignant primary brain tumor. Better surgical therapies are needed for newly diagnosed GBMs that are difficult to resect and for GBMs that recur despite standard therapies. The authors reviewed their institutional experience of using laser interstitial thermal therapy (LITT) for the treatment of newly diagnosed or recurrent GBMs. METHODS This study reports on the pre-LITT characteristics and post-LITT outcomes of 8 patients with newly diagnosed GBMs and 13 patients with recurrent GBM who underwent LITT. RESULTS Compared with the group with recurrent GBMs, the patients with newly diagnosed GBMs who underwent LITT tended to be older (60.8 vs 48.9 years), harbored larger tumors (22.4 vs 14.6 cm3), and a greater proportion had IDH wild-type GBMs. In the newly diagnosed GBM group, the median progression-free survival and the median survival after the procedure were 2 months and 8 months, respectively, and no patient demonstrated radiographic shrinkage of the tumor on follow-up imaging. In the 13 patients with recurrent GBM, 5 demonstrated a response to LITT, with radiographic shrinkage of the tumor following ablation. The median progression-free survival was 5 months, and the median survival was greater than 7 months. CONCLUSIONS In carefully selected patients with recurrent GBM, LITT may be an effective alternative to surgery as a salvage treatment. Its role in the treatment of newly diagnosed unresectable GBMs is not established yet and requires further study.

Neurophysiologic intraoperative monitoring in children with Down syndrome.

OBJECTIVE: Neurophysiological monitoring during complex spine procedures may reduce risk of injury by providing feedback to the operating surgeon. This tool is a well-established and important surgical adjunct in adults, but clinical data in children are not well described. Moreover, to the best of our knowledge, neurophysiologic intraoperative monitoring data have not been reported in children with neurodevelopmental disorders, such as Down syndrome, who commonly present with craniocervical instability requiring internal fixation. The purpose of this study is to determine the reliability and safety of neurophysiologic intraoperative monitoring in a group of children with Down syndrome undergoing neurosurgical spine procedures. METHODS: A total of six consecutive spinal procedures in six children with Down syndrome (three boys and three girls; mean age 10 years, range 4-16 years) were analyzed between January 1, 2008 and June 31, 2011. Somatosensory evoked potentials were stimulated at the ulnar nerve and tibial nerve for upper and lower extremities, respectively, and recorded at Erb's point and the scalp. Motor evoked potentials were elicited by transcranial electrical stimulation and recorded at the extensor carpi ulnaris muscle and tibialis anterior muscle for upper and lower extremities, respectively. A standardized anesthesia protocol for monitoring consisted of a titrated propofol drip combined with bolus dosing of fentanyl or sufentanil. RESULTS: Somatosensory and motor evoked potentials were documented at the beginning and end of the procedure in all six patients. Changes during the surgery were recorded. Five patients maintained somatosensory potentials throughout surgery. One patient demonstrated a >10% increase in latency or >50% decrease in amplitude suggesting spinal cord dysfunction. A mean baseline stimulation threshold for motor evoked potentials of 485 + 85 V (range 387-600 V) was used. Four patients maintained motor evoked potentials throughout surgery. One patient had loss of left lower somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) after rod placement; upon removal of the rod, SSEPs returned but not MEPs. Another patient did not have consistent MEPs on one side and had absent MEPs on the contralateral side throughout the case. Loss of MEPs in these two patients did not correlate with postoperative neurological status. There were no complications directly related to neurophysiologic intraoperative monitoring technique. CONCLUSIONS: Neurophysiologic intraoperative monitoring during neurosurgical procedures in children with Down syndrome may be reliably and safely implemented. Changes in neurophysiologic parameters during surgery must be carefully interpreted, and discussed with the neurosurgeon, neurophysiologist, and neuroanesthesiologist, and may not correlate with postoperative clinical changes. These changes may be related to abnormal physiology rather than an insult at the time of surgery. Nonetheless, the authors advocate routine neurophysiologic intraoperative monitoring in this special group of children undergoing neurosurgical spine procedures.

Safety and efficacy of salvage conventional re-irradiation following stereotactic radiosurgery for spine metastases.

PURPOSE: There has been limited work assessing the use of re-irradiation (re-RT) for local failure following stereotactic spinal radiosurgery (SSRS). We reviewed our institutional experience of conventionally-fractionated external beam radiation (cEBRT) for salvage therapy following SSRS local failure. MATERIALS AND METHODS: We performed a retrospective review of 54 patients that underwent salvage conventional re-RT at previously SSRS-treated sites. Local control following re-RT was defined as the absence of progression at the treated site as determined by magnetic resonance imaging. RESULTS: Competing risk analysis for local failure was performed using a Fine-Gray model. The median follow-up time was 25 months and median overall survival (OS) was 16 months (95% confidence interval [CI], 10.8-24.9 months) following cEBRT re-RT. Multivariable Cox proportional-hazards analysis revealed Karnofsky performance score prior to re-RT (hazard ratio [HR] = 0.95; 95% CI, 0.93-0.98; p = 0.003) and time to local failure (HR = 0.97; 95% CI, 0.94-1.00; p = 0.04) were associated with longer OS, while male sex (HR = 3.92; 95% CI, 1.64-9.33; p = 0.002) was associated with shorter OS. Local control at 12 months was 81% (95% CI, 69.3-94.0). Competing risk multivariable regression revealed radioresistant tumors (subhazard ratio [subHR] = 0.36; 95% CI, 0.15-0.90; p = 0.028) and epidural disease (subHR = 0.31; 95% CI, 0.12-0.78; p =0.013) were associated with increased risk of local failure. At 12 months, 91% of patients maintained ambulatory function. CONCLUSION: Our data suggest that cEBRT following SSRS local failure can be used safely and effectively. Further investigation is needed into optimal patient selection for cEBRT in the retreatment setting.

Brain stimulation for the treatment of epilepsy.

The treatment of patients with refractory epilepsy has always been challenging. Despite the availability of multiple antiepileptic medications and surgical procedures with which to resect seizure foci, there is a subset of epilepsy patients for whom little can be done. Currently available treatment options for these unfortunate patients include vagus nerve stimulation, the ketogenic diet, and electric stimulation, both direct and indirect, of brain nuclei thought to be involved in epileptogenesis. Studies of electrical stimulation of the brain in epilepsy treatment date back to the early 20th century, beginning with research on cerebellar stimulation. The number of potential targets has increased over the years to include the hippocampus, subthalamic nucleus, caudate nucleus, centromedian nucleus, and anterior nucleus of the thalamus (ANT). Recently the results of a large randomized controlled trial, the electrical Stimulation of the Anterior Nucleus of Thalamus for Epilepsy (SANTE) trial, were published, demonstrating a significant reduction in mean seizure frequency with ANT stimulation. Soon after, in 2011, the results of a second randomized, controlled trial-the NeuroPace RNS trial-were published. The RNS trial examined closed-loop, responsive cortical stimulation of seizure foci in patients with refractory partial epilepsy, again finding significant reduction in seizure frequency. In the present review, the authors examine the modern history of electrical stimulation of the brain for the treatment of epilepsy and discuss the results of 2 important, recently published trials, the SANTE and RNS trials.

Laser Interstitial Thermal Therapy for Glioblastoma: A Single-Center Experience.

BACKGROUND: Surgical resection has been shown to prolong survival in patients with glioblastoma multiforme (GBM), although this benefit has not been demonstrated for reoperation following tumor recurrence. Laser interstitial thermal therapy (LITT) is a minimally invasive ablation technique that has been shown to effectively reduce tumor burden in some patients with intracranial malignancy. The aim of this study was to describe the safety and efficacy of LITT for recurrent and newly diagnosed GBM at a large tertiary referral center. METHODS: Patients with GBM receiving LITT were retrospectively analyzed. Overall survival from the time of LITT was the primary end point measured. RESULTS: There were 69 patients identified for inclusion in this study. The median age of the cohort was 56 years (range, 15-77 years). Median tumor volume was 10.4 cm3 (range, 1.0-64.0 cm3). A Kaplan-Meier estimate of median overall survival for the series from the time of LITT was 12 months (95% confidence interval 8-16 months). Median progression-free survival for the cohort from LITT was 4 months (95% confidence interval 3-7 months). Adjuvant chemotherapy significantly prolonged progression-free survival and overall survival (P < 0.01 for both) in the cohort. Gross total ablation was not significantly associated with progression-free survival (P = 0.09). CONCLUSIONS: LITT can safely reduce intracranial tumor burden in patients with GBM who have exhausted other adjuvant therapies or are poor candidates for conventional resection techniques.

Ketogenic Diet for Malignant Gliomas: a Review.

PURPOSE OF REVIEW: In this review, we examine the postulated mechanisms of therapeutic effect of ketogenic diets in the treatment of gliomas, review the completed clinical trials, and discuss further directions in this field. RECENT FINDINGS: Cancers including gliomas are characterized by derangements in cellular metabolism. In vitro and animal studies have revealed that dietary interventions to reduce glucose and glycolytic pathways in gliomas may have a therapeutic effect. Early trials in patients with malignant gliomas have shown feasibility, but are not robust enough yet to demonstrate clinical applicability. Therapies for malignant gliomas of the brain are increasingly using a multi-targeted approach. The use of ketogenic diets and its variants may offer a unique and promising anti-glioma treatment by exploiting metabolic alterations seen in cancers including gliomas seen at the cellular level, which may work in concert with other therapies.

Ionizing radiation augments glioma tropism of mesenchymal stem cells.

OBJECTIVE Mesenchymal stem cells (MSCs) have been shown to localize to gliomas after intravascular delivery. Because these cells home to areas of tissue injury, the authors hypothesized that the administration of ionizing radiation (IR) to tumor would enhance the tropism of MSCs to gliomas. Additionally, they sought to identify which radiation-induced factors might attract MSCs. METHODS To assess the effect of IR on MSC migration in vitro, transwell assays using conditioned medium (CM) from an irradiated commercially available glioma cell line (U87) and from irradiated patient-derived glioma stem-like cells (GSCs; GSC7-2 and GSC11) were employed. For in vivo testing, green fluorescent protein (GFP)-labeled MSCs were injected into the carotid artery of nude mice harboring orthotopic U87, GSC7-2, or GSC17 xenografts that were treated with either 0 or 10 Gy of IR, and brain sections were quantitatively analyzed by immunofluorescence for GFP-positive cells. These GSCs were used because GSC7-2 is a weak attractor of MSCs at baseline, whereas GSC17 is a strong attractor. To determine the factors implicated in IR-induced tropism, CM from irradiated GSC7-2 and from GSC11 was assayed with a cytokine array and quantitative ELISA. RESULTS Transwell migration assays revealed statistically significant enhanced MSC migration to CM from irradiated U87, GSC7-2, and GSC11 compared with nonirradiated controls and in a dose-dependent manner. After their intravascular delivery into nude mice harboring orthotopic gliomas, MSCs engrafted more successfully in irradiated U87 (p = 0.036), compared with nonirradiated controls. IR also significantly increased the tropism of MSCs to GSC7-2 xenografts (p = 0.043), which are known to attract MSCs only poorly at baseline (weak-attractor GSCs). Ionizing radiation also increased the engraftment of MSCs in strong-attractor GSC17 xenografts, but these increases did not reach statistical significance. The chemokine CCL2 was released by GSC7-2 and GSC11 after irradiation in a dose-dependent manner and mediated in vitro transwell migration of MSCs. Immunohistochemistry revealed increased CCL2 in irradiated GSC7-2 gliomas near the site of MSC engraftment. CONCLUSIONS Administering IR to gliomas enhances MSC localization, particularly in GSCs that attract MSCs poorly at baseline. The chemokine CCL2 appears to play a crucial role in the IR-induced tropism of MSCs to gliomas.

A Novel Use of the Intraoperative MRI for Metastatic Spine Tumors: Laser Interstitial Thermal Therapy for Percutaneous Treatment of Epidural Metastatic Spine Disease.

Spinal laser interstitial thermal therapy (LITT) appears to be a promising novel modality for treatment of epidural metastatic spine disease in patients who are poor candidates for larger-scale oncologic spinal surgery and can act synergetically with spinal stereotactic radiosurgery to maximize local control and palliate pain. This technique is ideally suited for the intraoperative MRI suite to monitor the extent of the ablation in the epidural space. As percutaneous navigation, imaging, and LITT technology improve, broader applicability of this minimally invasive technique in spinal oncology is foreseen.

Image guidance based on MRI for spinal interstitial laser thermotherapy: technical aspects and accuracy.

OBJECTIVE Image guidance for spinal procedures is based on 3D-fluoroscopy or CT, which provide poor visualization of soft tissues, including the spinal cord. To overcome this limitation, the authors developed a method to register intraoperative MRI (iMRI) of the spine into a neuronavigation system, allowing excellent visualization of the spinal cord. This novel technique improved the accuracy in the deployment of laser interstitial thermal therapy probes for the treatment of metastatic spinal cord compression. METHODS Patients were positioned prone on the MRI table under general anesthesia. Fiducial markers were applied on the skin of the back, and a plastic cradle was used to support the MRI coil. T2-weighted MRI sequences of the region of interest were exported to a standard navigation system. A reference array was sutured to the skin, and surface matching of the fiducial markers was performed. A navigated Jamshidi needle was advanced until contact was made with the dorsal elements; its position was confirmed with intraoperative fluoroscopy prior to advancement into a target in the epidural space. A screenshot of its final position was saved, and then the Jamshidi needle was exchanged for an MRI-compatible access cannula. MRI of the exact axial plane of each access cannula was obtained and compared with the corresponding screenshot saved during positioning. The discrepancy in millimeters between the trajectories was measured to evaluate accuracy of the image guidance RESULTS Thirteen individuals underwent implantation of 47 laser probes. The median absolute value of the discrepancy between the location predicted by the navigation system and the actual position of the access cannulas was 0.7 mm (range 0-3.2 mm). No injury or adverse event occurred during the procedures. CONCLUSIONS This study demonstrates the feasibility of image guidance based on MRI to perform laser interstitial thermotherapy of spinal metastasis. The authors' method permits excellent visualization of the spinal cord, improving safety and workflow during laser ablations in the epidural space. The results can be extrapolated to other indications, including biopsies or drainage of fluid collections near the spinal cord.

Nuances in Localization and Surgical Treatment of Syringomyelia Associated with Fenestrated and Webbed Intradural Spinal Arachnoid Cyst: A Retrospective Analysis.

INTRODUCTION: Intradural spinal arachnoid cysts (SACs) are among many etiologies for syringomyelia. Consequentially, neurologic symptoms arise such as pain, gait disturbance, and bladder dysfunction. Identification of SAC on magnetic resonance imaging (MRI) can be challenging, as SACs can be fenestrated or in the form of fine webs. METHODS: Imaging and clinical data for 7 patients who underwent surgical treatment for SAC associated with syringomyelia were reviewed. All previous publications of this pathology were reviewed via MEDLINE search. RESULTS: Seven patients with a mean age 59 years were found to have a SAC causing syringomyelia. Intraoperative exploration confirmed SAC appearances of fine webs or a fluid-filled loculation impinging on the spinal cord. Common presentations were back pain, gait disturbance, and bladder incontinence. Diagnosis was made by MRI, although in 3 cases, the SAC was not identified on the initial review. Computed tomography myelogram was performed in one case due to the enlarged syringomyelia and lack of obvious spinal cord compression. Thoracic laminectomy/laminoplasty was performed for all patients, centered at the level of a subtle indentation of the cord; the syringomyelia proper was not directly addressed. Postoperatively, all patients had complete resolution of their symptoms with MRI demonstrating resolution of the syringomyelia. CONCLUSIONS: Careful evaluation of the MRI can demonstrate subtle indentation of the cord at the caudal or cephalad end of the syringomyelia and may obviate the need for additional imaging. Meticulous arachnoid dissection and establishment of good CSF flow is sufficient for resolution of the syringomyelia, averting the need for more aggressive procedures.

Fulminant spinal cord compression caused by postradiation inflammatory pseudotumor with rapid response to steroids: case report.

Radiation therapy continues to play an extremely valuable role in the treatment of malignancy. The effects of radiation therapy on normal tissue can present in a delayed fashion, resulting in localized damage with pseudomalignant transformation, producing a compressive effect on the spinal cord or exiting nerve roots. Infiltration of inflammatory cells and the subsequent fibrotic response can result in the development of an inflammatory pseudotumor (benign tumor-like lesion) with subsequent mass effect. Herein, the authors present a rare case of inflammatory pseudotumor with fulminant cervicothoracic cord compression, developing 7 years after radiation therapy for breast cancer. The lesion recurred following resection but subsequently displayed complete and rapid resolution following steroid therapy. To the best of the authors' knowledge, no previous studies have reported such an incident.

Malignant peripheral nerve sheath tumor of the cauda equina with craniospinal metastasis.

Intradural spinal malignant peripheral nerve sheath tumors (MPNST) are extremely rare, with only 20 adult patients reported to our knowledge, and only four primary tumors arising from the cauda equina. A 49-year-old man presented with back pain, constipation, and lower extremity weakness and was found to have a large intradural lesion involving the cauda equina. Imaging of the rest of his neuraxis revealed additional small left temporal lobe, cervical, and thoracic lesions. The patient underwent laminectomy for tumor debulking and biopsy, as gross total resection was not possible due to envelopment of the cauda equina. Histopathology revealed a MPNST with high cellularity, elevated proliferative indices, and nerve fascicle invasion. After the debulking, the patient reported improvement in his symptoms. However, 6 weeks later, the patient began having severe headaches, and his left temporal lobe lesion was found to have increased significantly in size, requiring craniotomy for palliative resection. The authors report the first adult patient with sporadic spinal MPNST with craniospinal metastasis to our knowledge. Imaging of the entire neuraxis is recommended for initial workup of these lesions, which are capable of intradural spread. The best treatment approach is unclear, but total surgical resection should be attempted, barring infiltration and engulfment of the nerve roots or widespread dissemination.

Prospective trial of a short hospital stay protocol after endoscopic endonasal pituitary adenoma surgery.

OBJECTIVE: Patients typically remain hospitalized for several days after transsphenoidal surgery for pituitary adenoma resection for reasons including pain control, serial neurological assessments, surveillance for cerebrospinal fluid leak, and management of endocrine issues. We sought to determine whether an evidence-based perioperative care protocol combined with an endoscopic approach could lead to routine and safe discharge on postoperative day 1. METHODS: Our multidisciplinary pituitary group prospectively implemented a perioperative care protocol that emphasizes patient education, early mobilization, and scheduled inpatient and outpatient endocrine assessments on 50 consecutive patients who underwent surgical resection of a pituitary adenoma (82% macroadenomas, 2.1 ± 0.8 cm, maximum 4.5 cm, 18% microadenomas). Endoscopic endonasal surgery characterized by aggressive tumor resection and avoidance of nasal packing and lumbar drains was used in all cases. Lengths of stay, readmissions, and postoperative outcomes were analyzed. RESULTS: Using the short-stay protocol, 92% (46 of 50) of patients were successfully discharged on postoperative day 1. The average length of stay for all patients was 1.16 ± 0.55 days (range 1 to 4). Postoperative diabetes insipidus occurred in 16% of patients (8 of 50), was effectively managed on an outpatient basis, and did not delay discharge. Readmission was required in 2 patients, in both cases for delayed presentation of a cerebrospinal fluid leak. CONCLUSIONS: A short-stay protocol allows for an overnight hospital stay for patients after pituitary surgery, with a low rate of complications or readmission. This study offers evidence-based guidelines that may be used to avoid complications and facilitate early discharge after transsphenoidal surgery.

Fixation with C-2 laminar screws in occipitocervical or C1-2 constructs in children 5 years of age or younger: a series of 18 patients.

UNLABELLED: OBJECT.: There are rare indications for upper cervical spine fusion in young children. Compared with nonrigid constructs, rigid instrumentation with screw fixation increases the fusion rate and reduces the need for halo fixation. Instrumentation may be technically challenging in younger children. A number of screw placement techniques have been described. Use of C-2 translaminar screws has been shown to be anatomically feasible, even in the youngest of children. However, there are few data detailing the clinical outcome. In this study, the authors describe the clinical and radiographic follow-up of 18 children 5 years of age or younger who had at least one C-2 translaminar screw as part of an occipitocervical or C1-2 fusion construct. METHODS: A retrospective review of all children treated with instrumented occipitocervical or C1-2 fusion between July 1, 2007, and June 30, 2013, at Riley Children's Hospital and Texas Children's Hospital was performed. All children 5 years of age or younger with incorporation of at least one C-2 translaminar screw were identified. RESULTS: Eighteen children were studied (7 boys and 11 girls). The mean age at surgery was 38.1 months (range 10-68 months). Indications for surgery included traumatic instability (6), os odontoideum (3), destructive processes (2), and congenital instability (7). A total of 24 C-2 translaminar screws were placed; 23 (95.8%) of 24 were satisfactorily placed (completely contained within the cortical walls). There was one medial cortex breach without neurological impingement. There were no complications with screw placement. Three patients required wound revisions. Two patients died as a result of their original condition (trauma, malignant tumor). The mean follow-up duration for the surviving patients was 17.5 months (range 3-60 months). Eleven (91.7%) of the 12 patients followed for 6 months or longer showed radiographic stability or completed fusion. CONCLUSIONS: Use of C-2 translaminar screws provides an effective anchor for internal fixation of the upper cervical spine. In this study of children 5 years of age or younger, the authors found a high rate of radiographic fusion with a low rate of complications.

Iatrogenic Creutzfeldt-Jakob disease via surgical instruments.

Creutzfeldt-Jakob disease (CJD) is a neurodegenerative prion disease that can spread via contaminated neurosurgical instruments previously used on an infected patient. We examine current guidelines on how to recognize, handle, and prevent instrument-related iatrogenic CJD. Despite only four reported patients worldwide implicating contaminated neurosurgical instruments, and none in the past 30 years, the public health consequences of potential instrument-related iatrogenic CJD can be far-reaching. Conventional sterilization and disinfection methods are inadequate in reducing prion infectivity of contaminated instruments, and World Health Organization recommendations for disinfection using bleach or sodium hydroxide are often impractical for routine decontamination. Recently, possible CJD exposure via infected surgical instruments was suspected at a large teaching hospital. Although CJD was later disproven, the intervening investigation exposed the difficulty in tracking infected surgical instruments and in protecting subsequent surgical patients from prion infection. To identify patients at risk for iatrogenic CJD, infectivity of instruments after this index patient is estimated using simple scenario modeling, assuming a certain log reduction of infectivity for each cleansing cycle. Scenario modeling predicts that after six cycles of instrument use with conventional cleansing following an index patient, other patients are highly unlikely to be at risk for iatrogenic CJD. Despite its rarity, the threat of iatrogenic CJD transmission via contaminated instruments poses tremendous challenges to neurosurgeons. Basic prevention strategies should be employed for patients with suspected CJD, including use of disposable instruments where possible and quarantining non-disposable instruments until the diagnosis is ascertained, or using special instrument reprocessing methods if CJD is suspected.

Endoscopic resection of tuberculum sellae meningiomas.

Objective To evaluate the results of endoscopic transnasal resection of tuberculum sellae meningiomas (TSMs) as compared with transcranial approaches. Design We retrospectively analyzed five patients who underwent endoscopic endonasal resection of TSM and performed a comprehensive review of articles published between 2000 and 2012 describing the operative treatment of TSMs. Results Gross total resection (GTR) was achieved in four patients (80%). Transient diabetes insipidus occurred in three patients (60%). Preoperative visual field deficit resolved in all patients. Cerebrospinal fluid (CSF) leak occurred in one patient. Analysis of published studies included 1,026 transcranial and 144 transnasal cases. GTR was achieved in 85% of transcranial and 72% of transnasal cases. Visual field deficit improved in 65% of transcranial and 82% of transnasal cases. Rate of diabetes insipidus and CSF leak was higher in the transnasal series. Rate of GTR and visual improvement was higher in endoscopic endonasal as compared with microsurgical transnasal series. Conclusion The literature supports transsphenoidal surgery for the resection of TSMs with significant optic nerve compromise and limited lateral extension. This approach may have an equivalent if not superior outcome over transcranial surgery in visual outcome. CSF leaks are still a challenge but may improve with the use of vascularized nasoseptal flaps.

Neurogenic claudication associated with posterior vertebral rim fractures in children.

OBJECT: Outside of the patient population with achondroplasia, neurogenic claudication is rare in the pediatric age group. Neurogenic claudication associated with posterior vertebral rim fracture is even more uncommon but nonetheless causes pain and disability in affected children and adolescents. The purpose of this study was to describe the surgical results of 3 adolescents presenting with neurogenic claudication and posterior vertebral rim fracture when treated with laminectomy alone. METHODS: The medical and operative records of the 3 pediatric patients were retrospectively reviewed. Presenting signs and symptoms and CT findings, such as the interpedicular distances between T-12 and L-5, were obtained. Perioperative results were assessed, including operative time, blood loss, length of hospital stay, and complications. Findings at latest follow-up were also recorded, including a patient satisfaction survey. RESULTS: The 3 patients (1 girl and 2 boys) had a mean age of 14.7 years (range 14-15 years) and underwent follow-up for a mean of 11.3 months (range 5-18 months). Notable preoperative signs and symptoms included back pain (all patients), leg pain (all patients), leg numbness (1 patient), and leg weakness (1 patient). No patient presented with bowel and/or bladder dysfunction. The mean blood loss during laminectomy was 123 ml (range 20-300 ml), and the mean length of hospital stay was 4.3 days (range 3-6 days). On average, decompression was performed at 2.2 levels (range 2-2.5 levels). All 3 patients reported at most recent follow-up that they were "satisfied" with the surgery. There was 1 complication of instability from an iatrogenic pars fracture, which required reoperation and posterior instrumented fusion. CONCLUSIONS: To the best of the authors' knowledge, this report represents the first surgical series of pediatric neurogenic claudication associated with posterior vertebral rim fractures. Pediatric neurosurgeons may infrequently encounter neurogenic claudication associated with a posterior vertebral rim fracture in children. To treat children with neurogenic claudication associated with posterior vertebral rim fractures, a simple laminectomy may be a safe and efficacious alternative to discectomy and removal of fracture fragments.

Correlation between shunt series and scoliosis radiographs in children with myelomeningoceles.

OBJECT: Over 85% of patients with myelomeningoceles require placement of a ventriculoperitoneal shunt for hydrocephalus, and between 25% and 85% of these patients develop scoliosis. Although most patients undergo repeated shunt series radiography to evaluate for device malfunction, scoliosis radiographs are less consistently obtained. The authors sought to determine if a correlation exists between these 2 radiographic techniques for a given patient, as shunt series are obtained with the patient supine, whereas scoliosis radiographs are acquired with the patient standing upright. The authors also endeavored to study if shunt series radiographs can reliably detect significant scoliosis. METHODS: The authors retrospectively reviewed a single institution's series of 593 patients with myelomeningoceles and identified all patients in whom a shunt series and scoliosis radiographs were obtained within a 6-month period. They reviewed the medical records and radiographs of these patients for demographic and radiographic parameters. They then applied a linear regression model and determined shunt series curve cutoffs to detect scoliotic curves greater than 20° and 50°. RESULTS: Of the 593 patients identified, 116 did not have radiographs available for interpretation. Of the remaining 477 patients, 201 had radiographic evidence of scoliosis (42%), and 66 had both a shunt series and a scoliosis radiographs acquired within a 6-month interval. In 4 patients, both end vertebrae of the scoliotic curve could not be visualized on a single radiograph. The mean age of the remaining cohort was 10.6 ± 5.2 years and the mean curve magnitude was 58° ± 37°. Using identical end vertebrae, the mean shunt series curve magnitude was 49° ± 35°. The mean interval between both radiographs was 2.3 ± 3.3 months. The regression model showed a strong linear association between shunt series and scoliosis series curves. A curve greater than 19° on shunt series radiographs would detect significant curves of greater than 20° on scoliosis series with 91% sensitivity and 78% specificity. A shunt series curve greater than 37° had 100% sensitivity and 93% specificity in identifying significant scoliotic curves greater than 50°. CONCLUSIONS: Although shunt series radiographs may not precisely depict scoliotic curve magnitude because the impact of gravity is negated, they may be useful in helping to confirm clinical suspicion of scoliosis. The authors' results suggest a strong correlation between both types of radiographs.

Surgical cannulation of a cortical draining vein for endovascular treatment of a dural arteriovenous fistula of the cavernous sinus.

Dural arteriovenous fistulas (DAVF) of the cavernous sinus most commonly present with ocular symptoms and can be observed or treated with endovascular approaches, surgery, or radiosurgery. Combined surgical-endovascular approaches have been used for fistulas that are not amenable to standard endovascular approaches. A 40-year-old man presented with ocular symptoms from a cavernous sinus DAVF. Multiple previous transarterial and transvenous embolization attempts had failed. The patient underwent craniotomy for surgical exposure and cannulation of an arterialized sylvian vein. Subsequently he underwent coiling and onyx embolization of the DAVF. The intervention resulted in effective obliteration of the fistula. If a cavernous sinus DAVF is refractory to treatment, surgical exposure and cannulation of a cortical draining vein can facilitate transvenous endovascular treatments.

Minimally invasive lumbar microdiscectomy in pediatric patients: a series of 6 patients.

OBJECT: Lumbar disc herniation is rare in the pediatric age group, but may still cause a significant amount of pain and disability. Whereas minimally invasive surgery (MIS) for lumbar disc herniation is routinely performed in adults, it has not yet been described in the pediatric population. The purpose of this study was to describe the surgical results of pediatric MIS-treated lumbar disc disease. METHODS: The authors retrospectively reviewed a series of 6 consecutive cases of lumbar microdiscectomy performed using MIS techniques between April 2008 and July 2010. Presenting symptoms, physical examination findings, and preoperative MR imaging results were obtained from medical records. Perioperative results, including blood loss, length of hospital stay, and complications were assessed. Findings at latest follow-up evaluation were also recorded. RESULTS: This report represents the first surgical series regarding pediatric lumbar microdiscectomies performed using MIS. The mean patient age was 16 years (range 14-17 years); there were 4 girls and 2 boys. Preoperative signs and symptoms of radiculopathic pain were notable in 100% of patients, and myotomal weakness was noted in 33% of patients. The first line of treatment in all patients was a period of conservative management lasting an average of 11.5 months (range 6-12 months). The mean intraoperative blood loss was 10.8 ml, and the mean postoperative length of stay was 1.3 days. There were no complications in this small series. CONCLUSIONS: The treatment of pediatric lumbar disc herniation by using MIS techniques can be safe and efficacious. However, further study with a larger number of patients and longer follow-up is needed to compare outcomes between MIS and open microdiscectomies.