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Dive into the research topics where Alexandra D. Beier is active.

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Featured researches published by Alexandra D. Beier.


Journal of Neurosurgery | 2012

Rotatory subluxation: experience from the Hospital for Sick Children

Alexandra D. Beier; Shobhan Vachhrajani; Simon H. Bayerl; Claudia Y. Diaz Aguilar; Maria Lamberti-Pasculli; James M. Drake

OBJECT Diagnosis and management of atlantoaxial rotatory subluxation (AARS) is challenging because of its variability in clinical presentation. Although several treatment modalities have been employed, there remains no consensus on the most appropriate therapy. The authors explore this issue in their 9-year series on AARS. METHODS Records of patients diagnosed radiologically and clinically with AARS between May 2001 and March 2010 were retrospectively reviewed. Of 40 patients identified, 24 were male and were on average 8.5 years of age (range 15 months-16 years). Causes of AARS included trauma, congenital abnormalities, juvenile rheumatoid arthritis, infection, postsurgical event, and cryptogenic disease. Four patients had dual etiologies. Symptom duration varied: 29 patients had symptoms for less than 4 weeks, 5 patients had symptoms between 1 and 3 months, and 6 patients had symptoms for 3 months or more. RESULTS Treatment with a cervical collar was sufficient in 21 patients. In 1 patient collar management failed and halter traction was used to reduce the subluxation. Seven patients underwent initial halter traction, but in 4 the subluxation progressed and the patients required halo traction. A halo vest was placed in 2 patients on presentation because the rotatory subluxation was severe; both patients required subsequent operative fusion. One patient required decompression and fusion due to severe canal compromise and myelopathy. All patients requiring fusion presented with subacute symptoms. CONCLUSIONS Management of AARS varies due to the spectrum of clinical presentations. Patients presenting acutely without neurological deficits can likely undergo collar therapy; those in whom the subluxation cannot be reduced or who present with a neurological deficit may require traction and/or surgical fixation. Patients presenting subacutely may be more prone to requiring operative intervention.


Journal of Neurosurgery | 2014

Pediatric brainstem hemorrhages after traumatic brain injury

Alexandra D. Beier; Peter Dirks

Traumatic brain injuries afflict a large number of pediatric patients. The most severe injuries lead to increased intracranial pressure and herniation, with resultant changes in the brainstem. Traumatic brainstem hemorrhages have previously been associated with poor neurological outcome and fatality. However, this report discusses 2 pediatric patients who sustained severe head trauma with subsequent brainstem hemorrhages, and yet experienced good neurological outcome; the possible mechanism is described.


Journal of Neurosurgery | 2010

Suprasellar arachnoid cyst resulting in the syndrome of inappropriate antidiuretic hormone secretion.

Alexandra D. Beier; Samuel H. Cheshier; Aabir Chakraborty; Peter Dirks

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is occasionally seen after hypothalamic injury or dysfunction, although it typically occurs in association with other endocrine disturbances. It is has never been described as a presenting feature of a suprasellar arachnoid cyst (SAC) in the pediatric population. The authors describe the case of an enlarging SAC resulting in SIADH as the only presenting feature, with an otherwise normal hypothalamic-pituitary axis. An SAC was diagnosed in utero in this 5-month-old girl who had a normal functioning hypothalamic-pituitary axis on presentation. Because of cyst enlargement and hydrocephalus, the patient was scheduled for surgery; however, preoperative labs revealed SIADH. After stabilizing the serum sodium concentration with fluid restriction and the administration of 3% sodium chloride, the patient underwent endoscopic cyst fenestration. Postoperatively, she had complete resolution of the SIADH. Syndrome of inappropriate antidiuretic hormone secretion as the presenting symptom of an SAC has not been previously described. In the aforementioned patient, the proposed mechanism for SIADH was enlargement of the suprasellar arachnoid cyst causing compression of the supraoptic and paraventricular nuclei and thus overstimulating the secretion of arginine vasopressin, which resulted in SIADH. The association of SIADH with an SAC is reportable, as is the resolution of the SIADH via cyst fenestration. The authors suggest that SIADH is an uncommon presenting feature of SACs and that syndrome resolution is possible with cyst decompression.


Neurosurgery | 2016

Guidelines: Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline for the Diagnosis of Patients with Positional Plagiocephaly: The Role of Imaging

Catherine A. Mazzola; Lissa C. Baird; David F. Bauer; Alexandra D. Beier; Susan Durham; Paul Klimo; Alexander Y. Lin; Catherine McClung-Smith; Laura Mitchell; Dimitrios Nikas; Mandeep S. Tamber; Rachana Tyagi; Ann Marie Flannery

BACKGROUND No evidence-based guidelines exist for the imaging of patients with positional plagiocephaly. OBJECTIVE The objective of this systematic review and evidence-based guideline is to answer the question, Is imaging necessary for infants with positional plagiocephaly to make a diagnosis? METHODS The National Library of Medicine Medline database and the Cochrane Library were queried with the use of MeSH headings and key words relevant to imaging as a means to diagnose plagiocephaly. Abstracts were reviewed, and an evidentiary table was assembled summarizing the studies and the quality of evidence (Classes I-III). Based on the quality of the literature, a recommendation was rendered (Level I, II, or III). RESULTS A total of 42 full-text articles were selected for review. Of these, 10 were eliminated; thus, 32 full-text were manuscripts selected. There was no Class I evidence, but 2 Class II and 30 Class III studies were included. Three-dimensional cranial topographical imaging, ultrasound, skull x-rays, computed tomography, and magnetic resonance imaging were investigated. CONCLUSION Clinical examination is most often sufficient to diagnose plagiocephaly (quality, Class III; strength, Level III). Within the limits of this systematic review, the evidence suggests that imaging is rarely necessary and should be reserved for cases in which the clinical examination is equivocal. Many of the imaging studies were not designed to address the diagnostic utility of the imaging modality, and authors were actually assessing the utility of the imaging in longitudinal follow-up, not initial diagnosis. For this reason, some of the studies reviewed were downgraded in Level of Evidence. When needed, 3-dimensional cranial topographical photo, skull x-rays, or ultrasound imaging is almost always sufficient for definitive diagnosis. Computed tomography scanning should not be used to diagnose plagiocephaly, but it may be necessary to rule out craniosynostosis. The full guidelines document can be located at https://www.cns.org/guidelines/guidelines-management-patients-positional-plagiocephaly/Chapter_2.


Neurosurgery | 2016

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for the Management of Patients with Positional Plagiocephaly: Executive Summary

Ann Marie Flannery; Mandeep S. Tamber; Catherine A. Mazzola; Paul Klimo; Lissa C. Baird; Rachana Tyagi; David F. Bauer; Alexandra D. Beier; Susan Durham; Alexander Y. Lin; Catherine McClung-Smith; Laura Mitchell; Dimitrios Nikas

BACKGROUND Positional plagiocephaly is a common problem seen by pediatricians, pediatric neurologists, and pediatric neurosurgeons. OBJECTIVE To create evidence-based guidelines for the treatment of pediatric positional plagiocephaly. METHODS This guideline was prepared by the Plagiocephaly Guideline Task Force, a multidisciplinary team made up of physician volunteers (clinical experts), medical librarians, and clinical guidelines specialists. The task force conducted a series of systematic literature searches of PubMed and the Cochrane Library, according to standard protocols for each topic addressed in subsequent chapters of this guideline. RESULTS The systematic literature searches returned 396 abstracts relative to the 4 main topics addressed in this guideline. The results were analyzed and are described in detail in each subsequent chapter included in this guideline. CONCLUSION Evidence-based guidelines for the management of infants with positional plagiocephaly will help practitioners manage this common disorder. The full guidelines documents can be located at https://www.cns.org/guidelines/guidelines-management-patients-positional-plagiocephaly.


World Neurosurgery | 2018

Pipeline Embolization Device Flow Diversion for a Dissecting Ruptured Posterior Cerebral Artery Aneurysm in a Pediatric Patient

Murillo Cunegatto-Braga; Brian Hogan; Pedro Aguilar-Salinas; Alexandra D. Beier; Ricardo A. Hanel

BACKGROUND Intracranial aneurysms (IAs) are rare in the pediatric population and are usually considered difficult to treat with traditional microsurgery owing to their complex morphology. Endovascular techniques have become the standard option for treating IAs in adults. More recently, flow diverters, such as the Pipeline embolization device (PED), are being widely adopted for unruptured IAs, with proven safety and efficacy in adults; however, their use in the pediatric population is not well defined. Here we report a pediatric patient with a ruptured posterior cerebral artery (PCA) aneurysm successfully treated with a PED, and provide a review of the literature on the current status of PED use in this subset of patients. CASE DESCRIPTION A previously healthy 4-year old boy presented to the emergency department with a subarachnoid hemorrhage. Magnetic resonance angiography (MRA) suggested a ruptured dissecting aneurysm in the right PCA. After discussing treatment options with the childs parents, off-label use of the PED device was chosen. A single PED device was successfully deployed within 24 hours of onset. At a 6-month follow-up, the patient was fully recovered, with a modified Rankin Scale score of 0, and MRA showed complete occlusion of the aneurysm and patency of the parent vessel. CONCLUSIONS Even though the PED has not received Food and Drug Administration approval to treat IAs in children, the literature reports favorable outcomes with this application. Thus, the PED may be a feasible option for treating challenging cases occurring more frequently in the pediatric population. Further studies in pediatric populations are needed to determine whether this technology is a viable and durable option for treating aneurysms in children.


Journal of Perinatology | 2018

Successful implementation of an intracranial hemorrhage (ICH) bundle in reducing severe ICH: a quality improvement project

Nicolas Chiriboga; Josef Cortez; Adriana Pena-Ariet; Kartikeya Makker; Carmen Smotherman; Shiva Gautam; Allison Blair Trikardos; Holly Knight; Mark Yeoman; Erin Burnett; Alexandra D. Beier; Inbal Cohen; Mark L. Hudak

ObjectiveOur specific, measurable, attainable, relevant, and time-limited (SMART) aim was to reduce the incidence of severe intracranial hemorrhage (ICH) among preterm infants born <30 weeks’ gestation from a baseline of 24% (January 2012–December 2013) to a long-term average of 11% by December 2015.Study designWe instituted an ICH bundle consisting of elements of the “golden hour” (delayed cord clamping, optimized cardiopulmonary resuscitation, improved thermoregulation) and provision of cluster care in the neonatal intensive care unit (NICU). We identified key drivers to achieve our SMART aims, and implemented quality improvement (QI) cycles: initiation of the ICH bundle, education of NICU staff, and emphasis on sustained adherence. We excluded infants born outside our facility and those with congenital anomalies.ResultsUsing statistical process control analysis (p-chart), the ICH bundle was associated with successful reduction in severe ICH (grade 3–4) in our NICU from a prebundle rate of 24% (January 2012–December 2013) to a sustained reduction over the next 4 years to an average rate of 9.7% by December 2017. Results during 2016–2017 showed a sustained improvement beyond the goal for 2014–2015. Over the same interval, there was improvement in admission temperatures [median 36.1 °C (interquartile range: 35.3–36.7 °C) vs. 37.1 °C (36.8–37.5 °C), p < 0.01] and a decrease in mortality rate [pre: 16/117 (14%) vs. post: 16/281 (6%), P < 0.01].ConclusionOur multidisciplinary QI initiative decreased severe ICH in our institution from a baseline rate of 24% to a lower rate of 9.7% over the ensuing 4 years. Intensive focus on sustained implementation of an ICH bundle protocol consisting of improved delivery room management, thermoregulation, and clustered care in the NICU was temporally associated with a clinically significant reduction in severe ICH.


Journal of Neurosurgery | 2018

Choroid plexus adenoma in a child: expanding the clinical and pathological spectrum

Nicole Prendergast; Jeffrey D. Goldstein; Alexandra D. Beier

Primary choroid plexus tumors encompass a variety of tumors, with choroid plexus papilloma and carcinoma being the most common. Also in the differential diagnosis is the rare benign choroid plexus adenoma. As these tumors are infrequently described, the histological profile continues to evolve. The authors present a case with unusual characteristics that will broaden the pathological spectrum for choroid plexus adenomas.


Acta Oncologica | 2017

Outcomes following proton therapy for pediatric ependymoma

Daniel J. Indelicato; Julie A. Bradley; Ronny L. Rotondo; Ronica H. Nanda; Natalie Logie; Eric Sandler; Philipp R. Aldana; Nathan J. Ranalli; Alexandra D. Beier; Christopher G. Morris; Nancy P. Mendenhall

Abstract Background: Proton therapy can reduce the low and intermediate radiation dose to uninvolved brain tissue in children with intracranial ependymomas, which may improve functional outcomes and reduce second malignancies in survivors. Accordingly, ependymoma has become the most common pediatric tumor treated with proton therapy, yet data on efficacy and toxicity are limited. Material and methods: Between June 2007 and February 2017, 179 children (≤21 years old) with nonmetastatic grade II/III intracranial ependymoma received proton therapy at our institution. Median age, 3.5 years (range, 0.7–21); 58% were male. Most (66%) tumors were in the posterior fossa and classified as WHO grade III (67%). 27% underwent multiple operations to maximize the extent of resection; ultimately 85% had a gross total or near total tumor resection before radiotherapy. 33% received preradiation chemotherapy. Median radiation dose in children ≤3 years old, 54 Gy(RBE). Most (>90%) children over 3 years old received 59.4 Gy(RBE). Patient and treatment variables were assessed for correlation with disease control. Results: Median follow-up, 3.2 years. 3-year local control, progression-free survival, and overall survival rates were 85%, 76%, and 90%, respectively. First site of progression was local, metastatic, or simultaneous in 14, 17 and 6 patients, respectively. On multivariate analysis, subtotal resection was associated with inferior local control (67% vs. 88%; p ≤ .01) and progression-free survival (59% vs. 79%; p < .05). Male sex was associated with inferior progression-free (67% vs. 87%; p< .05) and overall survival (84% vs. 99%; p < .01). The 3-year CTCAE grade 2 + brainstem toxicity rate was 5.5% (95% CI: 2.9–10.2), including 1 grade 5 toxicity. Conclusions: This series of proton therapy for pediatric intracranial ependymoma demonstrates disease control comparable to photon series without unexpected toxicity. Subtotal resection and male sex were associated with inferior disease control. Additional follow-up to quantify the expected reductions in late toxicity with proton therapy is ongoing.


Journal of Neurosurgery | 2016

Survival following decompressive hemicraniectomy for hemiconvulsion-hemiplegia-epilepsy syndrome: case report

Alexandra D. Beier; Gemi E. Jannotta; E. Dayan Sandler; Harry S. Abram; Raj D. Sheth; Philipp R. Aldana

Hemiconvulsion-hemiplegia-epilepsy (HHE) is an uncommon epileptic syndrome that affects young children. Typical management includes early initiation of benzodiazepines to abate the initial seizure activity quickly. Patients in whom epilepsy develops require prolonged use of antiepileptic agents. Herniation due to diffuse cerebral edema from HHE is rare; however, decompressive craniectomy has been described as a lifesaving measure. The authors present the case of a patient in whom a decompressive craniectomy was performed. They advocate a proactive approach in the detection and management of cerebral edema in HHE causing intracranial hypertension. In HHE cases that exhibit radiographic evidence of malignant cerebral edema (although not previously described in this disease, but similar to the setting of stroke and trauma), the authors advocate early neurosurgical consultation and evaluation for insertion of an intracranial pressure monitor for those patients who do not have a reliable neurological examination (i.e., Glasgow Coma Scale score ≤ 8).

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Dimitrios Nikas

University of Illinois at Chicago

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Paul Klimo

University of Tennessee Health Science Center

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