Kathryn M. Wagner

Neurosurgical management of brain metastases

Brain metastases present a significant public health issue, affecting more than 100,000 patients per year in the U.S. and result in significant morbidity. Brain metastases can occur in a variety of clinical situations ranging from multiple brain metastases with uncontrolled systemic disease to a solitary metastasis in the setting of controlled systemic disease. Additionally, advances in genomics have broadened the opportunities for targeted treatment options and potentially more durable systemic responses. As such, the treatment of brain metastases is now more tailored and multimodal, involving systemic, radiation, and surgical therapies, often in combination. This review discusses the historical and current role of neurosurgical techniques in the treatment of brain metastases.

Delayed intracranial hypertension after surgery for nonsyndromic craniosynostosis

A 2-month-old boy presented with an elongated (anteriorposterior) head shape, prominent wide forehead, and bitemporal narrowing. There was a visible and palpable bony keel along the sagittal suture that was present since birth [Figure 1]. He was the first child in the family, born at 40 weeks’ gestation, with no other obstetric, perinatal, or family history. His parents wished to pursue surgical correction of the sagittal synostosis, which he underwent with an unremarkable postoperative course. He continued to be followed annually as he enrolled in school. His parents have asked about the chances of requiring another surgery.

Intracranial venous hypertension in craniosynostosis: mechanistic underpinnings and therapeutic implications

Patients with complex, multisutural, and syndromic craniosynostosis (CSO) frequently exhibit intracranial hypertension. The intracranial hypertension cannot be entirely attributed to the craniocephalic disproportion with calvarial restriction because cranial vault expansion has not consistently alleviated elevated intracranial pressure. Evidence has most strongly supported a multifactorial interaction, including venous hypertension along with other pathogenic processes. Patients with CSO exhibit marked venous anomalies, including stenosis of the jugular-sigmoid complex, transverse sinuses, and extensive transosseous venous collaterals. These abnormal intracranial-extracranial occipital venous collaterals might represent anomalous development, with persistence and subsequent enlargement of channels normally present in the fetus, either as a primary defect or as nonregression in response to failure of the development of the jugular-sigmoid complexes. It has been suggested by some investigators that venous hypertension in patients with CSO could be treated directly via jugular foraminoplasty, venous stenting, or jugular venous bypass, although these options are not in common clinical practice. Obstructive sleep apnea, occurring as a consequence of midface hypoplasia, can also contribute to intracranial hypertension in patients with syndromic CSO. Thus, correction of facial deformities, as well as posterior fossa decompression, could also play important roles in the treatment of intracranial hypertension. Determining the precise mechanistic underpinnings underlying intracranial hypertension in any given patient with CSO requires individualized evaluation and management.

Cognitive Sequelae of Unruptured and Ruptured Intracranial Aneurysms and their Treatment: Modalities for Neuropsychological Assessment

BACKGROUND Cognitive sequelae frequently follow subarachnoid hemorrhage (SAH) and include deficits across multiple domains of executive function. This factor affects overall functional outcomes negatively, especially in younger patients. Several clinical correlates predict development and severity of cognitive dysfunction after SAH. Hypothetical mechanisms of cognitive dysfunction in the absence of radiographic lesion include cerebral hypoperfusion and blood breakdown products, resulting in perturbed interneuronal communication and network synchrony, excitotoxicity, and altered microRNA expression. METHODS The PubMed database was searched for articles discussing cognitive outcomes in patients with unruptured and ruptured intracranial aneurysmal disease, sequelae of treatment, and modalities for neuropsychologic testing. RESULTS Treatment of unruptured intracranial aneurysms, although capable of preventing SAH, comes with its own set of complications and may also affect cognitive function. Neuropsychological tests such as the Montreal Cognitive Assessment, Mini-Mental Status Examination, and others have proved useful in evaluating cognitive decline. Studies using functional neurologic imaging modalities have identified regions with altered activation patterns during various cognitive tasks. The sum of research efforts in this field has provided useful insights and an initial understanding of cognitive dysfunction after aneurysm treatment and SAH that should prove useful in guiding and rendering future investigations more fruitful. CONCLUSIONS Development of finer and more sensitive neuropsychological tests in evaluating the different domains of cognitive function after aneurysm treatment and SAH in general will be useful in accurately determining outcomes after ictus and comparing efficacy of different therapeutic strategies.

Neurosurgical Management of Single Brain Metastases

Brain metastasis is the most common type of intracranial tumor. The contemporary management of brain metastasis is a challenging issue and carries a poor prognosis, as traditionally it occurs in the setting of advanced systemic disease. Yet, as advances in systemic cancer treatment cause an increasing number of patients to develop brain metastases in the setting of limited systemic disease, the means for effectively treating them becomes more important. Surgery and stereotactic radiosurgery provide excellent therapeutic options for many such patients with single brain metastases. Concepts in managing brain metastasis are advancing, particularly with the judicious use of available techniques being applied as multimodal therapy tailored to the individual patient, which has now become the standard of care.

Anterior Choroidal Artery Aneurysms: Influence of Regional Microsurgical Anatomy on Safety of Endovascular Treatment

Several anatomical variables critically influence therapeutic strategizing for anterior choroidal artery (AChA) aneurysms, and specifically, the safety of flow diversion for these lesions. We review the microsurgical anatomy of the AChA, discussing and detailing these considerations in the treatment of AChA aneurysms, theoretically and in the light of our recent findings.

Unplanned intraoperative extubations in pediatric neurosurgery: analysis of case series to increase patient safety

OBJECTIVE Unplanned intraoperative extubations (UIEs), rare but high-risk events. Unintentional extubations are used as quality improvement metrics in neonatal and pediatric intensive care units, but intraoperative events have received scant attention in the literature. Complexity of patient positioning and proximity of the operative field to anesthesia make neurosurgical procedures unique. UIEs prolong operative time, increase risk of adverse outcomes, including cardiopulmonary collapse, and potentially require additional procedures. Investigating each event is critical to prevention. We aimed to analyze occurrences of UIEs in the pediatric population. METHODS We retrospectively reviewed UIE cases (12/2014-4/2017) in pediatric neurosurgical patients at a metropolitan pediatric Level I trauma center. Data were collected on patient demographics, procedure, operating room events before the event, and patient outcomes. RESULTS Over 27 months, 5 UIEs in pediatric neurosurgical cases occurred, with an event rate of <0.3%. Two occurred in patients <1 year old. Two UIEs occurred in patients undergoing surgery for epilepsy. Root cause analysis identified varied etiologies of UIE: 2 were attributed to endotracheal tube securement, 2 were attributed to lighter anesthesia planes in epilepsy cases with limb movement, and 1 occurred while supinating a prone patient. Postoperative outcomes for these patients were no different from routine cases. CONCLUSIONS Findings suggest an inverse correlation between patient age and UIE, with patient manipulation and anesthesia depth as risk factors. Meticulous attention to securing the endotracheal tube and streamlined communication between the surgical and anesthesia teams are critical for the goal of zero UIE occurrences.

Multimodal Treatment of Intracranial Aneurysms in Children: Clinical Case Series and Review of the Literature

BACKGROUND The management of intracranial aneurysms in the pediatric population presents unique challenges. Cases are rare and tend to be of higher complexity compared with aneurysms in adults. Outcomes in long-term follow-up are not well-characterized. Here we present illustrative case examples to demonstrate key concepts in managing these lesions in the context of the modern neurovascular era. METHODS Four institutional databases of neurovascular procedures from 2012 to 2017 were reviewed. Patients <18 years old who underwent treatment for intracranial aneurysms were included. Patient characteristics, aneurysm details, treatment information, and angiographic and clinical outcomes were recorded. RESULTS Ten cases of intracranial aneurysms in 9 children were identified. Management included direct clipping, trapping and bypass, endovascular coil embolization, endovascular vessel sacrifice, and flow diversion. CONCLUSIONS The management of intracranial aneurysms in pediatric patients requires special considerations, from the diagnostic phase to treatment methods and follow-up regimen. These are ideally considered by a multidisciplinary team, with expertise from pediatric neurosurgeons, cerebrovascular neurosurgeons, and neurointerventionalists.