The role of occipital condyle and atlas anomalies on occipital cervical fusion outcomes in Chiari malformation type I with syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium.

OBJECTIVE: Congenital anomalies of the atlanto-occipital articulation may be present in patients with Chiari malformation type I (CM-I). However, it is unclear how these anomalies affect the biomechanical stability of the craniovertebral junction (CVJ) and whether they are associated with an increased incidence of occipitocervical fusion (OCF) following posterior fossa decompression (PFD). The objective of this study was to determine the prevalence of condylar hypoplasia and atlas anomalies in children with CM-I and syringomyelia. The authors also investigated the predictive contribution of these anomalies to the occurrence of OCF following PFD (PFD+OCF). METHODS: The authors analyzed the prevalence of condylar hypoplasia and atlas arch anomalies for patients in the Park-Reeves Syringomyelia Research Consortium database who underwent PFD+OCF. Condylar hypoplasia was defined by an atlanto-occipital joint axis angle (AOJAA) ≥ 130°. Atlas assimilation and arch anomalies were identified on presurgical radiographic imaging. This PFD+OCF cohort was compared with a control cohort of patients who underwent PFD alone. The control group was matched to the PFD+OCF cohort according to age, sex, and duration of symptoms at a 2:1 ratio. RESULTS: Clinical features and radiographic atlanto-occipital joint parameters were compared between 19 patients in the PFD+OCF cohort and 38 patients in the PFD-only cohort. Demographic data were not significantly different between cohorts (p > 0.05). The mean AOJAA was significantly higher in the PFD+OCF group than in the PFD group (144° ± 12° vs 127° ± 6°, p < 0.0001). In the PFD+OCF group, atlas assimilation and atlas arch anomalies were identified in 10 (53%) and 5 (26%) patients, respectively. These anomalies were absent (n = 0) in the PFD group (p < 0.001). Multivariate regression analysis identified the following 3 CVJ radiographic variables that were predictive of OCF occurrence after PFD: AOJAA ≥ 130° (p = 0.01), clivoaxial angle < 125° (p = 0.02), and occipital condyle-C2 sagittal vertical alignment (C-C2SVA) ≥ 5 mm (p = 0.01). A predictive model based on these 3 factors accurately predicted OCF following PFD (C-statistic 0.95). CONCLUSIONS: The authors' results indicate that the occipital condyle-atlas joint complex might affect the biomechanical integrity of the CVJ in children with CM-I and syringomyelia. They describe the role of the AOJAA metric as an independent predictive factor for occurrence of OCF following PFD. Preoperative identification of these skeletal abnormalities may be used to guide surgical planning and treatment of patients with complex CM-I and coexistent osseous pathology.

Delayed Migration of Onyx Embolic Agent after Preoperative Embolization of an Arteriovenous Malformation in a Pediatric Patient: A Case Report and Review of the Literature.

INTRODUCTION: Brain arteriovenous malformations (AVMs) are increasingly being treated with Onyx liquid embolic agent (Onyx, Medtronic, Inc.). The phenomenon of delayed Onyx migration is not well documented in the literature. Moreover, the clinical presentation associated with Onyx migration is not well understood. CASE PRESENTATION: A pediatric patient with a history of neonatal seizures was referred to our institution upon experiencing daily headaches with photophobia, phonophobia, and sleep disturbance. Cerebral angiography revealed an AVM of the medial left cerebellar hemisphere. Preoperative embolization with Onyx liquid embolic achieved 25% closure of the AVM nidus. Upon developing worsening headaches the following day, new perinidal parenchymal edema was revealed on MRI, and urgent angiography demonstrated delayed migration of Onyx into the venous drainage. The patient underwent emergency resection of the AVM due to the risk of hemorrhage resulting from venous outflow obstruction. CONCLUSION: Our report and literature review demonstrate that while the delayed, unexpected migration of Onyx embolic material has been alluded to in a handful of papers, this phenomenon is not well documented. Future research is needed to understand the frequency of delayed Onyx migration from brain AVMs and the possible clinical presentations to look for. The sudden development of headaches and other signs of perilesional edema, in particular, should prompt repeat angiographic examination due to the possibility of delayed liquid embolic migration.

Repair of the superior sagittal sinus following penetrating intracranial injury caused by nail gun accident: case report and technical note.

We report a 45-year-old man who suffered a penetrating nail gun injury resulting in damage to the lateral edge of the superior sagittal sinus. The injury was successfully treated via a parasagittal craniotomy that enabled removal of the nail under direct vision, allowing for rapid suturing of the sagittal sinus. Two neurosurgeons worked together; one carefully withdrew the tip of the nail back into the sinus itself while the second rapidly sutured the hole in the inner superior sagittal sinus leaflet. Postoperatively, the patient made a rapid recovery without neurological deficit.

Preventing cerebral spinal fluid leakage following endoscopy through a burr hole using a novel watertight closure: technical note.

BACKGROUND: Cerebrospinal fluid (CSF) leakage is a common complication after neuroendoscopic surgery through a burr hole and can lead to further complications including infection. METHODS: We describe the use of a dural substitute larger than the burr hole itself, placed over the burr hole and then secured underneath a burr hole cover by microscrews running through the graft itself into the underlying skull. RESULTS: This simple technical modification contributes to achieving a watertight seal to aid in preventing CSF leakage in this setting. CONCLUSIONS: Our technical modification of endoscopy through a burr hole may help to prevent postoperative CSF leak and secondary CSF infections.

Complications and outcomes of posterior fossa decompression with duraplasty versus without duraplasty for pediatric patients with Chiari malformation type I and syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium.

OBJECTIVE: The aim of this study was to determine differences in complications and outcomes between posterior fossa decompression with duraplasty (PFDD) and without duraplasty (PFD) for the treatment of pediatric Chiari malformation type I (CM1) and syringomyelia (SM). METHODS: The authors used retrospective and prospective components of the Park-Reeves Syringomyelia Research Consortium database to identify pediatric patients with CM1-SM who received PFD or PFDD and had at least 1 year of follow-up data. Preoperative, treatment, and postoperative characteristics were recorded and compared between groups. RESULTS: A total of 692 patients met the inclusion criteria for this database study. PFD was performed in 117 (16.9%) and PFDD in 575 (83.1%) patients. The mean age at surgery was 9.86 years, and the mean follow-up time was 2.73 years. There were no significant differences in presenting signs or symptoms between groups, although the preoperative syrinx size was smaller in the PFD group. The PFD group had a shorter mean operating room time (p < 0.0001), fewer patients with > 50 mL of blood loss (p = 0.04), and shorter hospital stays (p = 0.0001). There were 4 intraoperative complications, all within the PFDD group (0.7%, p > 0.99). Patients undergoing PFDD had a 6-month complication rate of 24.3%, compared with 13.7% in the PFD group (p = 0.01). There were no differences between groups for postoperative complications beyond 6 months (p = 0.33). PFD patients were more likely to require revision surgery (17.9% vs 8.3%, p = 0.002). PFDD was associated with greater improvements in headaches (89.6% vs 80.8%, p = 0.04) and back pain (86.5% vs 59.1%, p = 0.01). There were no differences between groups for improvement in neurological examination findings. PFDD was associated with greater reduction in anteroposterior syrinx size (43.7% vs 26.9%, p = 0.0001) and syrinx length (18.9% vs 5.6%, p = 0.04) compared with PFD. CONCLUSIONS: PFD was associated with reduced operative time and blood loss, shorter hospital stays, and fewer postoperative complications within 6 months. However, PFDD was associated with better symptom improvement and reduction in syrinx size and lower rates of revision decompression. The two surgeries have low intraoperative complication rates and comparable complication rates beyond 6 months.

Expression of and correlational patterns among neuroinflammatory, neuropeptide, and neuroendocrine molecules from cerebrospinal fluid in cerebral palsy.

BACKGROUND: The underlying pathogenesis of cerebral palsy (CP) remains poorly understood. The possibility of an early inflammatory response after acute insult is of increasing interest. Patterns of inflammatory and related biomarkers are emerging as potential early diagnostic markers for understanding the etiologic diversity of CP. Their presence has been investigated in plasma and umbilical cord blood but not in cerebrospinal fluid (CSF). METHODS: A clinical CP sample was recruited using a single-time point cross-sectional design to collect CSF at point-of-care during a standard-of-care surgical procedure (intrathecal pump implant). Patient demographic and clinical characteristics were sourced from medical chart audit. RESULTS: Significant (p ≤ 0.001) associations were found among neuroinflammatory, neuroendocrine, and nociceptive analytes with association patterns varying by birth status (term, preterm, extremely preterm). When between birth-group correlations were compared directly, there was a significant difference between preterm and extremely preterm birth subgroups for the correlation between tumour necrosis factor alpha (TNFα) and substance P. CONCLUSION: This investigation shows that CSF can be used to study proteins in CP patients. Differences in inter-correlational patterns among analytes varying by birth status underscores the importance of considering birth status in relation to possible mechanistic differences as indicated by biomarker signatures. Future work should be oriented toward prognostic and predictive validity to continue to parse the heterogeneity of CP's presentation, pathophysiology, and response to treatment.

Traumatic epidural hematoma treated with endovascular coil embolization.

BACKGROUND: Traumatic cerebrovascular injury may result in epidural hematoma (EDH) from laceration of the middle meningeal artery (MMA), which is a potentially life-threatening emergency. Treatment ranges from surgical evacuation to conservative management based on a variety of clinical and imaging factors. CASE DESCRIPTION: A 14-year-old male presented to our institution after falling from his bicycle with traumatic subarachnoid hemorrhage and a right frontotemporal EDH. The patient did not meet criteria for surgical evacuation and endovascular embolization of the right MMA was performed. Rapid resolution of the EDH was observed. CONCLUSION: This case corroborates the sparse existing literature for the potential role of endovascular embolization to treat acute EDH in carefully selected patients who do not meet or have borderline indications for surgical management.

Transport of patients with giant disfiguring cranial tumors from Africa to the US for collaborative multidisciplinary treatment.

BACKGROUND: Giant disfiguring cranial tumors are exceptionally rare and develop over the course of many years, typically in patients who lack access to medical care. Here, we describe four patients who were flown to our center for treatment by a multidisciplinary surgical team, who had previously been turned down for treatment at multiple international centers in Africa, Europe, and the United States (US) due to complexity and financial concerns. The case series describes socioeconomic implications and the feasibility of offering such care to patients from outside the US. CASE DESCRIPTIONS: Four patients with giant skull disfiguring tumors were flown internationally and treated by a surgical team consisting of a complex cranial neurosurgeon, a craniofacial reconstructive plastic surgeon, and an oculoplastic surgeon. All patients underwent aggressive surgical therapy with the aim of complete tumor removal and simultaneous cranial reconstruction. A patient with osteogenic sarcoma underwent two additional resections in 3 years, with delayed reconstruction. They returned home but ultimately succumbed to the disease. A patient with ossifying fibroma required two follow-up procedures for cosmetic reconstruction and sought asylum in the US, where they remain today. Two additional patients, one with a giant plexiform neurofibroma and one with a cerebellopontine angle meningioma, achieved good results and returned to Africa 1 month and 3 weeks after surgery, respectively. CONCLUSION: Resection of giant disfiguring cranial tumors and reconstruction of the impacted region requires an experienced multidisciplinary team. These cases can be managed by transporting such patients from areas without access to medical care to specialized centers able to provide excellent care.

Extradural decompression versus duraplasty in Chiari malformation type I with syrinx: outcomes on scoliosis from the Park-Reeves Syringomyelia Research Consortium.

OBJECTIVE: Scoliosis is common in patients with Chiari malformation type I (CM-I)-associated syringomyelia. While it is known that treatment with posterior fossa decompression (PFD) may reduce the progression of scoliosis, it is unknown if decompression with duraplasty is superior to extradural decompression. METHODS: A large multicenter retrospective and prospective registry of 1257 pediatric patients with CM-I (tonsils ≥ 5 mm below the foramen magnum) and syrinx (≥ 3 mm in axial width) was reviewed for patients with scoliosis who underwent PFD with or without duraplasty. RESULTS: In total, 422 patients who underwent PFD had a clinical diagnosis of scoliosis. Of these patients, 346 underwent duraplasty, 51 received extradural decompression alone, and 25 were excluded because no data were available on the type of PFD. The mean clinical follow-up was 2.6 years. Overall, there was no difference in subsequent occurrence of fusion or proportion of patients with curve progression between those with and those without a duraplasty. However, after controlling for age, sex, preoperative curve magnitude, syrinx length, syrinx width, and holocord syrinx, extradural decompression was associated with curve progression > 10°, but not increased occurrence of fusion. Older age at PFD and larger preoperative curve magnitude were independently associated with subsequent occurrence of fusion. Greater syrinx reduction after PFD of either type was associated with decreased occurrence of fusion. CONCLUSIONS: In patients with CM-I, syrinx, and scoliosis undergoing PFD, there was no difference in subsequent occurrence of surgical correction of scoliosis between those receiving a duraplasty and those with an extradural decompression. However, after controlling for preoperative factors including age, syrinx characteristics, and curve magnitude, patients treated with duraplasty were less likely to have curve progression than patients treated with extradural decompression. Further study is needed to evaluate the role of duraplasty in curve stabilization after PFD.

Dural augmentation approaches and complication rates after posterior fossa decompression for Chiari I malformation and syringomyelia: a Park-Reeves Syringomyelia Research Consortium study.

OBJECTIVE: Posterior fossa decompression with duraplasty (PFDD) is commonly performed for Chiari I malformation (CM-I) with syringomyelia (SM). However, complication rates associated with various dural graft types are not well established. The objective of this study was to elucidate complication rates within 6 months of surgery among autograft and commonly used nonautologous grafts for pediatric patients who underwent PFDD for CM-I/SM. METHODS: The Park-Reeves Syringomyelia Research Consortium database was queried for pediatric patients who had undergone PFDD for CM-I with SM. All patients had tonsillar ectopia ≥ 5 mm, syrinx diameter ≥ 3 mm, and ≥ 6 months of postoperative follow-up after PFDD. Complications (e.g., pseudomeningocele, CSF leak, meningitis, and hydrocephalus) and postoperative changes in syrinx size, headaches, and neck pain were compared for autograft versus nonautologous graft. RESULTS: A total of 781 PFDD cases were analyzed (359 autograft, 422 nonautologous graft). Nonautologous grafts included bovine pericardium (n = 63), bovine collagen (n = 225), synthetic (n = 99), and human cadaveric allograft (n = 35). Autograft (103/359, 28.7%) had a similar overall complication rate compared to nonautologous graft (143/422, 33.9%) (p = 0.12). However, nonautologous graft was associated with significantly higher rates of pseudomeningocele (p = 0.04) and meningitis (p < 0.001). The higher rate of meningitis was influenced particularly by the higher rate of chemical meningitis (p = 0.002) versus infectious meningitis (p = 0.132). Among 4 types of nonautologous grafts, there were differences in complication rates (p = 0.02), including chemical meningitis (p = 0.01) and postoperative nausea/vomiting (p = 0.03). Allograft demonstrated the lowest complication rates overall (14.3%) and yielded significantly fewer complications compared to bovine collagen (p = 0.02) and synthetic (p = 0.003) grafts. Synthetic graft yielded higher complication rates than autograft (p = 0.01). Autograft and nonautologous graft resulted in equal improvements in syrinx size (p < 0.0001). No differences were found for postoperative changes in headaches or neck pain. CONCLUSIONS: In the largest multicenter cohort to date, complication rates for dural autograft and nonautologous graft are similar after PFDD for CM-I/SM, although nonautologous graft results in higher rates of pseudomeningocele and meningitis. Rates of meningitis differ among nonautologous graft types. Autograft and nonautologous graft are equivalent for reducing syrinx size, headaches, and neck pain.

Occipital-Cervical Fusion and Ventral Decompression in the Surgical Management of Chiari-1 Malformation and Syringomyelia: Analysis of Data From the Park-Reeves Syringomyelia Research Consortium.

BACKGROUND: Occipital-cervical fusion (OCF) and ventral decompression (VD) may be used in the treatment of pediatric Chiari-1 malformation (CM-1) with syringomyelia (SM) as adjuncts to posterior fossa decompression (PFD) for complex craniovertebral junction pathology. OBJECTIVE: To examine factors influencing the use of OCF and OCF/VD in a multicenter cohort of pediatric CM-1 and SM subjects treated with PFD. METHODS: The Park-Reeves Syringomyelia Research Consortium registry was used to examine 637 subjects with cerebellar tonsillar ectopia ≥ 5 mm, syrinx diameter ≥ 3 mm, and at least 1 yr of follow-up after their index PFD. Comparisons were made between subjects who received PFD alone and those with PFD + OCF or PFD + OCF/VD. RESULTS: All 637 patients underwent PFD, 505 (79.2%) with and 132 (20.8%) without duraplasty. A total of 12 subjects went on to have OCF at some point in their management (PFD + OCF), whereas 4 had OCF and VD (PFD + OCF/VD). Of those with complete data, a history of platybasia (3/10, P = .011), Klippel-Feil (2/10, P = .015), and basilar invagination (3/12, P < .001) were increased within the OCF group, whereas only basilar invagination (1/4, P < .001) was increased in the OCF/VD group. Clivo-axial angle (CXA) was significantly lower for both OCF (128.8 ± 15.3°, P = .008) and OCF/VD (115.0 ± 11.6°, P = .025) groups when compared to PFD-only group (145.3 ± 12.7°). pB-C2 did not differ among groups. CONCLUSION: Although PFD alone is adequate for treating the vast majority of CM-1/SM patients, OCF or OCF/VD may be occasionally utilized. Cranial base and spine pathologies and CXA may provide insight into the need for OCF and/or OCF/VD.

Delayed Onset of an Intradural Epidermoid Tumor in the Lumbar Region Seven Years After Spinal Anesthesia for Childbirth: A Case Report.

Epidural or spinal anesthesia is commonly administered in births in the US, and the potential risks for epidermoid tumors are not well-characterized. We present the case of a 29-year-old female patient who developed an intradural epidermoid tumor in the lumbar spine, discovered seven years after spinal anesthesia for childbirth. MRI revealed a 4 cm tumor filling the entire spinal canal. Pathology confirmed the mass to be an epidermoid. Complete surgical resection of the intradural lesion was accomplished with full symptomatic relief. This case supports the relationship between delayed development of epidermoid tumors and spinal puncture in adult populations.

Factors associated with syrinx size in pediatric patients treated for Chiari malformation type I and syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium.

OBJECTIVE: Factors associated with syrinx size in pediatric patients undergoing posterior fossa decompression (PFD) or PFD with duraplasty (PFDD) for Chiari malformation type I (CM-I) with syringomyelia (SM; CM-I+SM) are not well established. METHODS: Using the Park-Reeves Syringomyelia Research Consortium registry, the authors analyzed variables associated with syrinx radiological outcomes in patients (< 20 years old at the time of surgery) with CM-I+SM undergoing PFD or PFDD. Syrinx resolution was defined as an anteroposterior (AP) diameter of ≤ 2 mm or ≤ 3 mm or a reduction in AP diameter of ≥ 50%. Syrinx regression or progression was defined using 1) change in syrinx AP diameter (≥ 1 mm), or 2) change in syrinx length (craniocaudal, ≥ 1 vertebral level). Syrinx stability was defined as a < 1-mm change in syrinx AP diameter and no change in syrinx length. RESULTS: The authors identified 380 patients with CM-I+SM who underwent PFD or PFDD. Cox proportional hazards modeling revealed younger age at surgery and PFDD as being independently associated with syrinx resolution, defined as a ≤ 2-mm or ≤ 3-mm AP diameter or ≥ 50% reduction in AP diameter. Radiological syrinx resolution was associated with improvement in headache (p < 0.005) and neck pain (p < 0.011) after PFD or PFDD. Next, PFDD (p = 0.005), scoliosis (p = 0.007), and syrinx location across multiple spinal segments (p = 0.001) were associated with syrinx diameter regression, whereas increased preoperative frontal-occipital horn ratio (FOHR; p = 0.007) and syrinx location spanning multiple spinal segments (p = 0.04) were associated with syrinx length regression. Scoliosis (HR 0.38 [95% CI 0.16-0.91], p = 0.03) and smaller syrinx diameter (5.82 ± 3.38 vs 7.86 ± 3.05 mm; HR 0.60 [95% CI 0.34-1.03], p = 0.002) were associated with syrinx diameter stability, whereas shorter preoperative syrinx length (5.75 ± 4.01 vs 9.65 ± 4.31 levels; HR 0.21 [95% CI 0.12-0.38], p = 0.0001) and smaller pB-C2 distance (6.86 ± 1.27 vs 7.18 ± 1.38 mm; HR 1.44 [95% CI 1.02-2.05], p = 0.04) were associated with syrinx length stability. Finally, younger age at surgery (8.19 ± 5.02 vs 10.29 ± 4.25 years; HR 1.89 [95% CI 1.31-3.04], p = 0.01) was associated with syrinx diameter progression, whereas increased postoperative syrinx diameter (6.73 ± 3.64 vs 3.97 ± 3.07 mm; HR 3.10 [95% CI 1.67-5.76], p = 0.003), was associated with syrinx length progression. PFD versus PFDD was not associated with syrinx progression or reoperation rate. CONCLUSIONS: These data suggest that PFDD and age are independently associated with radiological syrinx improvement, although forthcoming results from the PFDD versus PFD randomized controlled trial (NCT02669836, clinicaltrials.gov) will best answer this question.

Musculoskeletal Pain Outcomes Pre- and Post Intrathecal Baclofen Pump Implant in Children With Cerebral Palsy: A Prospective Cohort Study.

OBJECTIVE: To characterize musculoskeletal pain intensity, duration, frequency, and interference with activities of daily living in children with cerebral palsy (CP) before and after intrathecal baclofen pump placement. DESIGN: Prospective cohort study. SETTING: Children's tertiary hospital. PARTICIPANTS: Participants were children with CP (N=32; 53% male; mean age, 9.9y; age range, 4-17y). The majority of participants had a CP diagnosis of quadriplegia (76%) and relied on wheeled mobility (91%). INTERVENTIONS: Assessments were completed pre- and post intrathecal baclofen pump implant. MAIN OUTCOME MEASURES: Because of considerable patient heterogeneity, both pain measures (Brief Pain Inventory, Dalhousie Pain Interview) were completed by proxy (parent) report at the time of the procedure and approximately 6 months after intrathecal baclofen (ITB) pump placement. RESULTS: Prior to implant, 31% of participants were living with constant pain, which reduced to 6% post ITB implant (P<.001). Based on Wilcoxon signed rank tests, pain duration significantly decreased post ITB pump implant (P<.01). CONCLUSIONS: This prospective analysis supports the anecdotal and retrospective evidence that musculoskeletal pain decreases in CP following ITB pump implant. The greatest effect appears to be on the duration of pain experience. Pain did not decrease for all individuals, and it would be worth further investigation to better understand the relation between patient characteristics and pain outcomes.

Microvascular decompression with partial occipital condylectomy in a case of pediatric spasmodic torticollis.

Spasmodic torticollis is a rare, neurologic disorder that is caused by abnormal nerve compression of the 11th cranial nerve by blood vessels or bony protrusions. It is typically treated pharmacologically and, if necessary, with surgical intervention. We report a unique case of spasmodic torticollis in a 15-year-old female that involved abnormal compression of the left 11th cranial nerve (CN) by the left vertebral artery, displaced by a hypertrophic left occipital condyle. After treatment with Botox was unsuccessful, the patient was treated with microvascular decompression and occipital condylectomy that adequately relieved the abnormal compression of CN XI. Mild symptoms persisted, and the patient underwent a partial section of the sternocleidomastoid muscle 1 year later, after which torticollis symptoms resolved.

Air gun orbitocranial penetrating injury: emergency endovascular treatment and surgical bypass following pellet migration to middle cerebral artery: case report.

The authors describe a 14-year-old boy presenting with an orbitocranial penetrating injury (OPI) from a metallic air gun pellet to the left eye who developed hemiparesis and speech difficulty due to migration of the pellet to the left middle cerebral artery. They highlight the potential complications associated with both OPIs and intravascular foreign body migration and occlusion by describing the patient's presentation, results of imaging evaluation, and the combined endovascular treatment and extracranial-intracranial bypass, which resulted in rapid restoration of blood flow and full neurological recovery with intact vision. Based on this case and a review of the literature on intracranial foreign body migration with resultant vascular occlusion, the authors recommend that complex OPIs be treated at centers that offer both neuroendovascular and neurovascular surgical capabilities on an urgent basis to manage both the primary injury and potential secondary vascular compromise.

Limited vertical dural opening for lesions of the vermis, 4(th) ventricle, and distal PICA segments.

BACKGROUND: Lesions of the vermis and 4(th) ventricle are commonly addressed through a midline suboccipital approach. Most neurosurgeons use either a Y-shaped or a curvilinear dural opening in this setting. Although these approaches offer a wide intraoperative surgical exposure, in occasion, the dural opening is difficult to repair primarily, often necessitating the use of a patch, which may increase the risk for development of CSF fistula. We are describing our experience with a limited, vertical, midline, dural opening for approaches to the vermis, tentorium, 4(th) ventricle, and distal posterior-inferior cerebellar artery (PICA) segments as an alternative to the classic Y-shaped or curvilinear incision. METHODS: We report our experience with a limited vertical midline durotomy in five patients with posterior fossa lesions. The lesions treated included a PICA dissecting aneurysm, three metastatic lesions (located in the vermian, floor of the 4(th) ventricle, and undersurface of the tentorium cerebelli), and one intra-axial tumor (ependymoma). All patients were positioned prone, and the lesions were accessed without difficulty through a limited, vertical, midline durotomy. RESULTS: Mass lesions and vascular abnormalities located from the midline as far lateral as the outlet foramina of the 4(th) ventricle can be accessed comfortably via a limited midline dural opening when combined with microsurgical techniques, and the use of a frameless Stealth Station Neuronavigation System (SSNS) [Medtronic Sofamor Danek, Inc., Memphis, TN]. By doing this, simple primary dural closure was achieved with a single running absorbable suture without tension in each case. CONCLUSION: In our experience, a suboccipital linear dural opening appears to be as effective as the more traditional Y-shaped incision, yet allows for quicker and easier primary dural repair.

New resorbable plate and screw system in pediatric craniofacial surgery.

Early forms of resorbable fixation induced foreign body reactions requiring surgical removal of the fixation material. Most current plating systems attempt to circumvent this phenomenon by altering the composition of the α esters involved. ResorbX (KLS Martin, Jacksonville, FL), a plating system derived from 50:50 poly(D,L)lactide, boasts short resorption times, minimal foreign body reaction, and adequate strength for bony fixation. We present our experience with 134 patients undergoing correction of primary craniosynostosis, using ResorbX. One hundred thirty-four consecutive craniosynostosis patients underwent correction with calvarial remodeling by the senior author between April 2002 and March 2008. Five patients had 2-stage repairs. Postoperative analysis included plate visibility or palpability, head contour, and the incidence of complications. The mean age at repair was 17.0 months, with the median age being 9.0 months (range, 2.5-137 months). Postoperative follow-up visits were recorded at 3-month intervals from 0 to 24 months. Synostosis diagnoses were as follows: 43 metopic, 37 sagittal, 27 coronal, 5 lambdoid, and 27 multisutural synostosis. There were 3 complications requiring operative intervention. Three plates became exposed through the coronal excision, requiring removal, for an overall complication rate of 2%. Forty-four patients (31.7%) had a visible mass at the site of fixation at some point postoperatively; all of these resolved through observation only. Overall postoperative head aesthetics were deemed satisfactory to excellent, and no instances of contour regression occurred. This study documents the safety and efficacy of ResorbX in pediatric cranial vault remodeling. The system is easy to use, and with the advent of an ultrasonic pin, more abbreviated operating and anesthesia times are achievable.

Pentasomy 49,XXXXY associated with a Chiari type 1 malformation and cervical syrinx.

Pentasomy 49,XXXXY occurs in 1/85,000 newborn males. The origin of this particular form of aneuploidy is believed to be a result of consecutive nondisjunction events during maternal meiosis. Typical presentation consists of hypotonia, developmental delay, various dysmorphic features, and severe hypogenitalism. A 13-year-old with pentasomy 49,XXXXY and a Chiari type 1 malformation with an associated cervical syrinx is presented.