Magnetic resonance imaging of traumatic injury to the craniovertebral junction: a case-based review.

OBJECT: The craniovertebral junction (CVJ) is unique in the spinal column regarding the degree of multiplanar mobility allowed by its bony articulations. A network of ligamentous attachments provides stability to this junction. Although ligamentous injury can be inferred on CT scans through the utilization of craniometric measurements, the disruption of these ligaments can only be visualized directly with MRI. Here, the authors review the current literature on MRI evaluation of the CVJ following trauma and present several illustrative cases to highlight the utility and limitations of craniometric measures in the context of ligamentous injury at the CVJ. METHODS: A retrospective case review was conducted to identify patients with cervical spine trauma who underwent cervical MRI and subsequently required occipitocervical or atlantoaxial fusion. Craniometric measurements were performed on the CT images in these cases. An extensive PubMed/MEDLINE literature search was conducted to identify publications regarding the use of MRI in the evaluation of patients with CVJ trauma. RESULTS: The authors identified 8 cases in which cervical MRI was performed prior to operative stabilization of the CVJ. Craniometric measures did not reliably rule out ligamentous injury, and there was significant heterogeneity in the reliability of different craniometric measurements. A review of the literature revealed several case series and descriptive studies addressing MRI in CVJ trauma. Three papers reported the inadequacy of the historical Traynelis system for identifying atlantooccipital dislocation and presented 3 alternative classification schemes with emphasis on MRI findings. CONCLUSIONS: Recognition of ligamentous instability at the CVJ is critical in directing clinical decision making regarding surgical stabilization. Craniometric measures appear unreliable, and CT alone is unable to provide direct visualization of ligamentous injury. Therefore, while the decision to obtain MR images in CVJ trauma is largely based on clinical judgment with craniometric measures used as an adjunct, a high degree of suspicion is warranted in the care of these patients as a missed ligamentous injury can have devastating consequences.

Idiopathic syringomyelia: retrospective case series, comprehensive review, and update on management.

OBJECT: A syrinx is a fluid-filled cavity within the spinal cord that can be an incidental finding or it can be accompanied by symptoms of pain and temperature insensitivity. Although it is most commonly associated with Chiari malformation Type I, the advancement of imaging techniques has resulted in more incidental idiopathic syringes that are not associated with Chiari, tumor, trauma, or postinfectious causes. The authors present a comprehensive review and management strategies for the idiopathic variant of syringomyelia. METHODS: The authors retrospectively identified 8 idiopathic cases of syringomyelia at their institution during the last 6 years. A PubMed/Medline literature review yielded an additional 38 articles. RESULTS: Two of the authors' patients underwent surgical treatment that included a combination of laminectomy, lysis of adhesions, duraplasty, and syrinx fenestration. The remaining 6 patients were treated conservatively and had neurologically stable outcomes. Review of the literature suggests that an etiology-driven approach is essential in the diagnosis and management of syringomyelia, although conservative management suffices for most cases. In particular, it is important to look at disturbances in CSF flow, as well as structural abnormalities including arachnoid webs, cysts, scars, and a diminutive posterior fossa. CONCLUSIONS: The precise etiology for idiopathic syringomyelia (IS) is still unclear, although conceptual advances have been made toward the overall understanding of the pathophysiology of IS. Various theories include the cerebellar piston theory, intramedullary pulse pressure theory, and increased spinal subarachnoid pressure. For most patients with IS, conservative management works well. Continued progression of symptoms, however, could be approached using decompressive strategies such as laminectomy, lysis of adhesions, and craniocervical decompression, depending on the level of pathology. Management for patients with progressive neurological dysfunction and the lack of flow disturbance is unclear, although syringosubarachnoid shunting can be considered.

Comparative assessment of thermal injury induced by bipolar electrocautery systems in a porcine model.

BACKGROUND: Bipolar electrocautery systems used during neurosurgical procedures have been shown to induce thermal injury to surrounding tissue. The goal of this study was to compare the thermal injury induced by two different systems commonly used in neurosurgical procedures (Silverglide by Stryker Corporation and SpetzlerMalis by Codman Neuro), with that of a newly introduced device (TRIOwand by NICO Corporation). METHODS: A farm swine underwent craniectomy and durotomy with subsequent exposure of cortical brain tissue. Electrocoagulation for the duration of 3 s was conducted with three different bipolar systems under comparable power settings. The maximal depth of thermal injury and mean area of injury in Hematoxylin and Eosin stained slides were quantified using Image J. The tissues were evaluated for vacuolization and ischemic damage. One-way ANOVA followed by post hoc Tukey test was utilized for statistical analysis. Alpha level was set at 0.05. RESULTS: TRIOwand lesions showed less depth of injury when compared to both Spetzler-Malis (P < 0.001) and Silverglide lesions (P = 0.048). Silverglide lesions showed significantly less depth of injury when compared to SpetzlerMalis lesions (P < 0.001). The injury area induced by the TRIOwand was significantly less than that of Spetzler-Malis (P < 0.001) and Silverglide systems (P < 0.001). Ischemic changes and vacuolization were seen in all three groups. CONCLUSION: Thermal damage is induced to varying extents by all bipolar systems. In this porcine model and under the conditions tested, bipolar cauterization with the TRIOwand resulted in less depth and decreased mean area of injury. Further studies are needed to characterize the injury caused by different bipolar systems with other settings and under surgical conditions in humans.

Meta-analysis on the treatment options and outcomes of carotid blood blister aneurysms.

OBJECTIVE: Carotid blister aneurysms remain a formidable surgical challenge with varied surgical options. There have been significant advancements in the endovascular management of these aneurysms with the introduction of flow diverters. The comparative risk profiles for different endovascular options compared to surgical management of these lesions is not completely understood. METHODS: The study is a comprehensive systematic review and meta-analysis on the treatment of carotid blood blister aneurysms. Pubmed searches were used to identify relevant articles and patient level data was extracted. Two and three group analyses were conducted comparing surgical and endovascular strategies and surgical, stent coil and flow diversion techniques respectively. Patient outcomes were graded on the modified Rankin Scale with a score of 2 or less defined as favorable. RESULTS: In total, 83 studies (41 and 42 studies on surgical and endovascular interventions, respectively) with 1119 patients met our inclusion criteria. A statistically significant difference (at the 5% level of significance) in the effect among three different interventions was not found (Q = 3.41, p = 0.1815) under the random-effect model. Our results did show summary proportions of favorable outcomes were higher in the stent coil (0.87, 95% CI: 0.79 - 0.94) and flow diversion (0.87, 95% CI: 0.75 - 0.96) than that of surgery (0.76, 95% CI: 0.71 - 0.83). CONCLUSIONS: Our results suggest a trend towards improved patient outcomes with endovascular techniques compared to surgical strategies but statistical significance was not achieved. We also found that endovascular techniques compare favorably. Increasing retreatments were found to negatively affect patient outcomes.

Minimally Invasive Parafascicular Surgery (MIPS) for Spontaneous Intracerebral Hemorrhage Compared to Medical Management: A Case Series Comparison for a Single Institution.

OBJECTIVE: We compared the safety and effectiveness of minimally invasive parafascicular surgery (MIPS) as a frontline treatment for spontaneous supratentorial ICH to medical management. Patients. The sample consisted of 17 patients who underwent MIPS from January 2014 to December 2016 and a comparison group of 23 patients who were medically managed from June 2012 to December 2013. All had an International Classification of Disease (ICD) diagnosis of 431 and were treated at Grady Memorial Hospital, an urban, public, safety-net hospital. METHODS: The primary endpoint was risk of inpatient mortality. Secondary endpoints were rates of inpatient infection and favorable discharge status, defined as discharge to home or rehabilitation facility. Demographics and pre- and postclinical outcomes were compared using t-tests, the Mann-Whitney test, and chi-squared tests for continuous, ordinal and categorical measures, respectively. Cox proportional hazard models were used to estimate the time to inpatient death. Logistic regression analyses were used to determine treatment effects on secondary outcomes. We also conducted exploratory subgroup analyses which compared MIPS to two medical management subgroups: those who had surgery during their hospitalization and those that did not. RESULTS: Two patients (12%) died in the MIPS group compared to three (12%) in the medical management group. MIPS did not increase the risk of inpatient mortality relative to medical management. Rates of inpatient infection did not differ significantly between the two groups; eight MIPS patients (47%) and 13 medically managed patients (50%) contracted infections. MIPS significantly increased the likelihood of favorable discharge status (odds ratio (OR) 1.77; 95% CI, 1.12-21.9) compared to medical management. No outcome measures were significantly different between MIPS and the medical management subgroup without surgery, while rates of favorable discharge were higher among the MIPS patients compared to the medical management group with surgery. CONCLUSIONS: These data suggest that MIPS, as a frontline treatment for spontaneous ICH, versus medical management for spontaneous ICH warrants further investigation.

Volume of left Heschl's Gyrus and linguistic pitch learning.

Research on the contributions of the human nervous system to language processing and learning has generally been focused on the association regions of the brain without considering the possible contribution of primary and adjacent sensory areas. We report a study examining the relationship between the anatomy of Heschl's Gyrus (HG), which includes predominately primary auditory areas and is often found to be associated with nonlinguistic pitch processing and language learning. Unlike English, most languages of the world use pitch patterns to signal word meaning. In the present study, native English-speaking adult subjects learned to incorporate foreign pitch patterns in word identification. Subjects who were less successful in learning showed a smaller HG volume on the left (especially gray matter volume), but not on the right, relative to learners who were successful. These results suggest that HG, typically shown to be associated with the processing of acoustic cues in nonspeech processing, is also involved in speech learning. These results also suggest that primary auditory regions may be important for encoding basic acoustic cues during the course of spoken language learning.

Bimusicalism: The Implicit Dual Enculturation of Cognitive and Affective Systems.

One prominent example of globalization and mass cultural exchange is bilingualism, whereby world citizens learn to understand and speak multiple languages. Music, similar to language, is a human universal, and subject to the effects of globalization. In two experiments, we asked whether bimusicalism exists as a phenomenon, and whether it can occur even without explicit formal training and extensive music-making. Everyday music listeners who had significant exposure to music of both Indian (South Asian) and Westerners traditions (IW listeners) and listeners who had experience with only Indian or Western culture (I or W listeners) participated in recognition memory and tension judgment experiments where they listened to Western and Indian music. We found that while I and W listeners showed an in-culture bias, IW listeners showed equal responses to music from both cultures, suggesting that dual mental and affective sensitivities can be extended to a nonlinguistic domain.

Microsurgical Treatment of Cerebral Aneurysms After Previous Endovascular Therapy: Single-Center Series and Systematic Review.

BACKGROUND: Since its introduction in the early 1990s, endovascular treatment of cerebral aneurysms has had a steady upward trend and is the primary mode of treatment for most intracranial aneurysms. Concurrently, the need for retreatment of aneurysms after previous endovascular treatment has continued to increase, some of which can only be treated with microsurgical techniques. The factors that dictate outcomes in this group of patients are incompletely understood. OBJECTIVE: To study factors contributing to patient outcomes after microsurgical treatment of aneurysms with previous endovascular treatment. METHODS: The records of the senior author (D.L.B.) since 2002 were retrospectively reviewed for aneurysms treated after previous endovascular treatment. Demographics, treatment details, and imaging were reviewed for all patients. A systematic review of the literature on microsurgical treatment of aneurysms previously treated by endovascular therapy was also conducted. RESULTS: A total of 91 patients were identified from the retrospective review. Mean age at the time of initial treatment was 49 ± 12.68 years. Most patients initially presented with subarachnoid hemorrhage before initial endovascular treatment, with only 11 patients (12%) presenting with incidentally discovered lesions. Modified Rankin Scale score at discharge after initial treatment was good (0-3) in 81.4% of cases. Functional outcomes at the last known follow-up showed a modified Rankin Scale score of 0-3 in 77 patients (84.6%). Only aneurysm neck size was found to be a significant predictor of surgical complications (Wald χ2 = 10.79; P = 0.0010) with an odds ratio of 2.32 (95% confidence interval, 1.40-3.83) for a 2-mm increase in neck size. Systematic review identified 37 studies who were used to pool data on 370 patients. Although type of surgery was identified as a predictor of poor outcomes, this was significantly confounded by Hunt and Hess grade in the systematic review. CONCLUSIONS: Favorable outcomes can be obtained even for highly complex cerebral aneurysms that have failed endovascular treatment at high-volume cerebrovascular centers. Initial presentation grade and aneurysm size are important predictors of final patient outcomes.

Pipeline embolization device treatment of internal carotid artery terminus aneurysms.

BACKGROUND: The pipeline embolization device (PED) is approved for the treatment of large aneurysms of the proximal internal carotid artery (ICA). Its off-label application in treating aneurysms located specifically at the ICA terminus (ICA-T) has not been studied. METHODS: We conducted a retrospective chart review of patients from 2011 to 7 treated with PEDs. Out of 365 patients, 10 patients with ICA-T aneurysms were included. Patient demographics, procedural information, follow-up imaging, and clinical assessments were recorded. RESULTS: Mean age was 46.9 years (± 8.8), and 6 (60%) patients were women. The mean maximum diameter of the aneurysms treated was 14.7 mm (± 10.7) and the mean neck diameter was 9.3 mm (± 6.6). Reasons for presentation included six incidental findings, one acute subarachnoid hemorrhage (SAH), and three patients with prior SAH. Kamran-Byrne Occlusion Scale scores for the treated aneurysms were as follows: three class IV (complete obliteration), four class III (<50% filling in both height and width for fusiform aneurysms or residual neck for saccular aneurysms), one class II fusiform aneurysm, 1 class 0 saccular aneurysm (residual aneurysm body), and one not classified due to pipeline thrombosis. Two clinically asymptomatic complications were noted: one patient who had a small distal cortical SAH post PED and one patient whose stent was found to be thrombosed on follow-up angiogram. All patients were seen in follow-up, and no patients were found to have worsening of their pre-procedure modified Rankin Scale score. CONCLUSION: The PED has potential for treating ICA-T aneurysms not amenable to conventional treatment strategies. Further studies are warranted to confirm the long term outcomes.

Pipeline Embolization of Vertebrobasilar Aneurysms-A Multicenter Case Series.

BACKGROUND: The Pipeline Embolization Device (PED) has been increasingly used for the treatment of posterior circulation aneurysms. The purpose of the present study was to examine the clinical and angiographic outcomes of patients with vertebrobasilar aneurysms treated with the PED. METHODS: We performed a retrospective review of vertebrobasilar aneurysms treated with the PED at 4 high-volume neurovascular centers. Patient, aneurysm, and procedural data were collected, including perioperative and delayed complications. Aneurysm occlusion on follow-up imaging studies was defined as complete (100%), near-complete (>90%), or incomplete (<90%) occlusion. RESULTS: The cohort included 35 patients with 37 vertebrobasilar aneurysms who underwent 36 treatment sessions. Of the 35 patients, 10 were men (29%), and the mean patient age was 54.1 years (range, 32-75). Eight patients (23%) underwent urgent treatment because of a ruptured aneurysm (n = 6), brainstem perforator stroke (n = 1), or post-traumatic pseudoaneurysm (n = 1). Of the 37 aneurysms, 22 arose from the vertebral artery (59%) and 15 from the basilar artery (41%). Also, 19 were saccular aneurysms (51%), with a mean size of 7.7 mm (range, 1.7-38.0); 17 were fusiform aneurysms (46%), with a mean size of 11.0 mm (range, 4.3-34); and 1 was a 2.9-mm blister aneurysm. The overall procedural complication rate was 14% (5 of 36), including 3 neurologically symptomatic complications. At a mean follow-up period of 14 months (range, 3-59), 24 of 34 aneurysms (71%) were completely occluded and 29 of 34 (85%) were completely or near-completely occluded. CONCLUSION: Our results show that Pipeline embolization of vertebrobasilar aneurysms is associated with acceptable occlusion and complication rates.

The role of inflammation and potential use of sex steroids in intracranial aneurysms and subarachnoid hemorrhage.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) continues to be a devastating neurological condition with a high risk of associated morbidity and mortality. Inflammation has been shown to increase the risk of complications associated with aSAH such as vasospasm and brain injury in animal models and humans. The goal of this review is to discuss the inflammatory mechanisms of aneurysm formation, rupture and vasospasm and explore the role of sex hormones in the inflammatory response to aSAH. METHODS: A literature review was performed using PubMed using the following search terms: "intracranial aneurysm," "cerebral aneurysm," "dihydroepiandrosterone sulfate" "estrogen," "hormone replacement therapy," "inflammation," "oral contraceptive," "progesterone," "sex steroids," "sex hormones" "subarachnoid hemorrhage," "testosterone." Only studies published in English language were included in the review. RESULTS: Studies have shown that administration of sex hormones such as progesterone and estrogen at early stages in the inflammatory cascade can lower the risk and magnitude of subsequent complications. The exact mechanism by which these hormones act on the brain, as well as their role in the inflammatory cascade is not fully understood. Moreover, conflicting results have been published on the effect of hormone replacement therapy in humans. This review will scrutinize the variations in these studies to provide a more detailed understanding of sex hormones as potential therapeutic agents for intracranial aneurysms and aSAH. CONCLUSION: Inflammation may play a role in the pathogenesis of intracranial aneurysm formation and subarachnoid hemorrhage, and administration of sex hormones as anti-inflammatory agents has been associated with improved functional outcome in experimental models. Further studies are needed to determine the therapeutic role of these hormones in the intracranial aneurysms and aSAH.

Current Perspectives in Imaging Modalities for the Assessment of Unruptured Intracranial Aneurysms: A Comparative Analysis and Review.

BACKGROUND: Intracranial aneurysms (IAs) are pathologic dilatations of cerebral arteries. This systematic review summarizes and compares imaging techniques for assessing unruptured IAs (UIAs). This review also addresses their uses in different scopes of practice. Pathophysiologic mechanisms are reviewed to better understand the clinical usefulness of each imaging modality. METHODS: A literature review was performed using PubMed with these search terms: "intracranial aneurysm," "cerebral aneurysm," "magnetic resonance angiography (MRA)," computed tomography angiography (CTA)," "catheter angiography," "digital subtraction angiography," "molecular imaging," "ferumoxytol," and "myeloperoxidase". Only studies in English were cited. RESULTS: Since the development and improvement of noninvasive diagnostic imaging (computed tomography angiography and magnetic resonance angiography), many prospective studies and meta-analyses have compared these tests with gold standard digital subtraction angiography (DSA). Although computed tomography angiography and magnetic resonance angiography have lower detection rates for UIAs, they are vital in the treatment and follow-up of UIAs. The reduction in ionizing radiation and lack of endovascular instrumentation with these modalities provide benefits compared with DSA. Novel molecular imaging techniques to detect inflammation within the aneurysmal wall with the goal of stratifying risk based on level of inflammation are under investigation. CONCLUSIONS: DSA remains the gold standard for preoperative planning and follow-up for patients with IA. Newer imaging modalities such as ferumoxytol-enhanced magnetic resonance imaging are emerging techniques that provide critical in vivo information about the inflammatory milieu within aneurysm walls. With further study, these techniques may provide aneurysm rupture risk and prediction models for individualized patient care.

Endovascular Treatment of Posterior Inferior Cerebellar Artery Aneurysms with Flow Diversion.

BACKGROUND: Flow diversion is a viable alternative for treatment of wide-neck and fusiform aneurysms originating from the posterior inferior cerebellar artery (PICA), but coverage of the PICA and vertebral perforating arteries may be a concern. The aim of this study was to examine procedural, clinical, and angiographic outcomes of patients with PICA aneurysms treated with the Pipeline Embolization Device. METHODS: Retrospective review was performed of PICA aneurysms treated with the Pipeline device at 3 neurovascular centers, including periprocedural complications and clinical and angiographic outcomes. RESULTS: In 16 procedures, 14 PICA aneurysms were treated with the Pipeline device. These included 11 saccular aneurysms with a mean size of 7.4 mm (range, 2.0-11.1 mm) and 3 fusiform aneurysms with a mean diameter of 6.1 mm (range, 5.0-8.0 mm) and mean length of 10.3 mm (range, 6.0-15.0 mm). One patient developed a PICA territory infarct with mild leg weakness that resolved in <7 days. Overall complication rate was 7% (1/14) per patient and 6% (1/16) per procedure. Mean duration of clinical follow-up was 13.5 months (range, 3 weeks to 61.7 months), with all patients returning to baseline functional status. Complete or near-complete aneurysm occlusion was achieved in 58% (7/12) of cases with angiographic follow-up (mean, 15 months; range, 4-61 months). All covered PICAs remained patent. CONCLUSIONS: Flow diversion of PICA aneurysms is a safe and viable treatment option when traditional endovascular options are unlikely to preserve parent vessel patency.

Reduced Efficacy of the Pipeline Embolization Device in the Treatment of Posterior Communicating Region Aneurysms with Fetal Posterior Cerebral Artery Configuration.

BACKGROUND: Aneurysms at the origin of the posterior communicating artery (PcommA) have been demonstrated to be effectively treated with the pipeline embolization device (PED). Much less is known about the efficacy of the PED for aneurysms associated with a fetal posterior cerebral artery (fPCA) variant. OBJECTIVE: To study PED treatment efficacy of PcommA aneurysms, including fPCA aneurysms. METHODS: A prospectively maintained university database of aneurysm patients treated with the PED was retrospectively reviewed. Demographics, treatment details, and imaging were reviewed for all PcommA and fPCA aneurysms. RESULTS: Out of a total of 285 patients treated with PED, 50 patients (mean age 57.5 ± 12.2 yr, 42 females) with unruptured PcommA (9 fPCA) aneurysms were identified. Mean follow-up duration was 14.0 ± 11.6 mo (48 patients). Roy-Raymond class I occlusion on follow-up magnetic resonance or catheter angiography (mean time 11.7 ± 6.8 mo) was achieved in 30 patients (62.5%), class II occlusion in 11 patients (22.9%) and class III occlusion in 7 patients (14.5%). The PcommA was occluded in 56% of patients without any clinical symptoms. No deaths or permanent neurological complications occurred. In fPCA aneurysms, class I occlusion was seen in 1 patient, class 2 occlusion in 2 patients, and class III occlusion in 6 patients. Multivariate analysis revealed an independent association between incomplete occlusion and fPCA configuration (OR 73.65; 95% CI: 5.84-929.13; P = .001). CONCLUSION: The PED is a safe and effective treatment for PcommA aneurysms, although fetal anatomy should increase consideration of traditional endovascular techniques or surgical clipping.

Endovascular Treatment of Posterior Cerebral Artery Aneurysms With Flow Diversion: Case Series and Systematic Review.

BACKGROUND: Flow diversion of posterior cerebral artery (PCA) aneurysms has not been widely reported, possibly owing to concerns regarding parent vessel size and branch vessel coverage. OBJECTIVE: To examine the safety and effectiveness of PCA aneurysm flow diverter treatment. METHODS: Retrospective review of PCA aneurysms treated with the Pipeline Embolization Device (PED; Medtronic Inc, Dublin, Ireland) at 3 neurovascular centers, including periprocedural complications and clinical and angiographic outcomes. Systematic review of the literature identified published reports of PCA aneurysms treated with flow diversion. Rates of aneurysm occlusion and complications were calculated, and outcomes of saccular and fusiform aneurysm treatments were compared. RESULTS: Ten PCA aneurysms in 9 patients were treated with the PED. There were 2 intraprocedural thromboembolic events (20%), including 1 symptomatic infarction and 1 delayed PED thrombosis. Eight of 10 patients returned to or improved from their baseline functional status. Complete aneurysm occlusion with parent vessel preservation was achieved in 75% (6/8) of cases at mean follow-up of 16.7 mo. Eleven of 12 (92%) major branch vessels covered by a PED remained patent. Including the present study, systematic review of 15 studies found a complete aneurysm occlusion rate of 88% (30/34) and complication rate of 26% (10/38), including 5 symptomatic ischemic strokes (13%; 5/38). Fusiform aneurysms more frequently completely occluded compared with saccular aneurysms (100% vs 70%; P = .03) but were associated with a higher complication rate (43% vs 9%; P = .06). CONCLUSION: The safety and effectiveness profile of flow diverter treatment of PCA aneurysms may be acceptable in select cases.

Reoperations within 48 hours following 7942 pediatric neurosurgery procedures.

OBJECTIVE Various indicators are used to evaluate the quality of care delivered by surgical services, one of which is early reoperation rate. The indications and rate of reoperations within a 48-hour time period have not been previously reported for pediatric neurosurgery. METHODS Between May 1, 2009, and December 30, 2014, 7942 surgeries were performed by the pediatric neurosurgery service in the operating rooms at a single institution. Demographic, socioeconomic, and clinical characteristics associated with each of the operations were prospectively collected. The procedures were grouped into 31 categories based on the nature of the procedure and underlying diseases. Reoperations within 48 hours at the conclusion of the index surgery were reviewed to determine whether the reoperation was planned or unplanned. Multivariate logistic regression was employed to analyze risk factors associated with unplanned reoperations. RESULTS Cerebrospinal fluid shunt-and hydrocephalus-related surgeries accounted for 3245 (40.8%) of the 7942 procedures. Spinal procedures, craniotomy for tumor resections, craniotomy for traumatic injury, and craniofacial reconstructions accounted for an additional 8.7%, 6.8%, 4.5%, and 4.5% of surgical volume. There were 221 reoperations within 48 hours of the index surgery, yielding an overall incidence of 2.78%; 159 of the reoperation were unplanned. Of these 159 unplanned reoperations, 121 followed index operations involving shunt manipulations. Using unplanned reoperations as the dependent variable (n = 159), index operations with a starting time after 3 pm and admission through the emergency department (ED) were associated with a two- to threefold increase in the likelihood of reoperations (after-hour surgery, odds ratio [OR] 2.01 [95% CI 1.43-2.83, p < 0.001]; ED admission, OR 1.97 (95% CI 1.32-2.96, p < 0.05]). CONCLUSIONS Approximately 25% of the reoperations within 48 hours of a pediatric neurosurgical procedure were planned. When reoperations were unplanned, contributing factors could be both surgeon related and system related. Further study is required to determine the extent to which these reoperations are preventable. The utility of unplanned reoperation as a quality indicator is dependent on proper definition, analysis, and calculation.

Carotid cavernous fistula after Pipeline placement: a single-center experience and review of the literature.

OBJECTIVE: Carotid cavernous fistula (CCF) development after Pipeline Embolization Device (PED) treatment of cavernous carotid aneurysms (CCA) can be a challenging pathology to treat for the neurointerventionalist. METHODS: A database of all patients whose aneurysms were treated with the PED since its approval by the Food and Drug Administration in 2011 was retrospectively reviewed. Demographic information, aneurysm characteristics, treatment technique, antiplatelet regimen, and follow-up data were collected. A literature review of all papers that describe PED treatment of CCA was then completed. RESULTS: A total of 44 patients with 45 CCAs were identified (38 women, 6 men). The mean age was 59.9±9.0 years. The mean maximal aneurysm diameter was 15.9±6.9 mm (mean neck 7.1±3.6 mm). A single PED was deployed in 32 patients, with two PEDs deployed in 10 patients and three PEDs in 3 patients. Adjunctive coiling was performed in 3 patients. Mean follow-up duration based on final imaging (MR angiography or digital subtraction angiography) was 14.1±12.2 months. Five patients (11.4%) developed CCFs in the post-procedural period after PED treatment, all within 2 weeks of device placement. These CCFs were treated with a balloon test occlusion followed by parent artery sacrifice. Our literature review yielded only three reports of CCFs after PED placement, with the largest series having a CCF rate of 2.3%. CONCLUSIONS: CCF formation is a known risk of PED treatment of CCA. Although transvenous embolization can be used for treating CCFs, parent artery sacrifice remains a viable option on the basis of these data. Studies support the view that adjunctive coiling may have a protective effect against post-PED CCF formation. None of the coiled aneurysms in our database or in the literature have ruptured. Follow-up data will lead to a better understanding of the safety profile of the PED for CCA.

Subacute Posttraumatic Ascending Myelopathy After an Incomplete Spinal Cord Injury from a Gunshot Wound to the Spine: Case Report and Review of the Literature.

BACKGROUND: Subacute posttraumatic ascending myelopathy (SPAM) is a rare event that occurs after spinal cord trauma or ischemia. SPAM is defined as progressive loss of spinal cord or nerve root function days to weeks after the initial trauma that cannot be attributed to mechanical instability. Because of the rarity of this condition, there is no clear understanding of its cause, natural history, or treatment guidelines for patient management. CASE DESCRIPTION: Here, we present the first reported case of SPAM after a gunshot wound to the spine. In this case, the patient presented with a mild spinal cord injury that recovered after surgery but then progressed to a more severe spinal cord injury many days later. Magnetic resonance imaging before and after his new symptoms supported the diagnosis of SPAM. CONCLUSIONS: This case demonstrates that spinal cord injury is a dynamic lesion, both in the immediate postinjury stage and in the subacute time interval as well. This is the first reported case of SPAM that occurred after the resolution of incomplete SCI and only the second that occurred after a gunshot wound.