Activity of a Novel Anti-Inflammatory Agent F-3,6'-dithiopomalidomide as a Treatment for Traumatic Brain Injury

Traumatic brain injury (TBI) is a major risk factor for several neurodegenerative disorders, including Parkinson's disease (PD) and Alzheimer's disease (AD). Neuroinflammation is a cause of later secondary cell death following TBI, has the potential to aggravate the initial impact, and provides a therapeutic target, albeit that has failed to translate into clinical trial success. Thalidomide-like compounds have neuroinflammation reduction properties across cellular and animal models of TBI and neurodegenerative disorders. They lower the generation of proinflammatory cytokines, particularly TNF-α which is pivotal in microglial cell activation. Unfortunately, thalidomide-like drugs possess adverse effects in humans before achieving anti-inflammatory drug levels. We developed F-3,6'-dithiopomalidomide (F-3,6'-DP) as a novel thalidomide-like compound to ameliorate inflammation. F-3,6'-DP binds to cereblon but does not efficiently trigger the degradation of the transcription factors (SALL4, Ikaros, and Aiolos) associated with the teratogenic and anti-proliferative responses of thalidomide-like drugs. We utilized a phenotypic drug discovery approach that employed cellular and animal models in the selection and development of F-3,6'-DP. F-3,6'-DP significantly mitigated LPS-induced inflammatory markers in RAW 264.7 cells, and lowered proinflammatory cytokine/chemokine levels in the plasma and brain of rats challenged with systemic LPS. We subsequently examined immunohistochemical, biochemical, and behavioral measures following controlled cortical impact (CCI) in mice, a model of moderate TBI known to induce inflammation. F-3,6'-DP decreased CCI-induced neuroinflammation, neuronal loss, and behavioral deficits when administered after TBI. F-3,6'-DP represents a novel class of thalidomide-like drugs that do not lower classical cereblon-associated transcription factors but retain anti-inflammatory actions and possess efficacy in the treatment of TBI and potentially longer-term neurodegenerative disorders.

3,6'- and 1,6'-Dithiopomalidomide Mitigate Ischemic Stroke in Rats and Blunt Inflammation

(1) Background: An important concomitant of stroke is neuroinflammation. Pomalidomide, a clinically available immunomodulatory imide drug (IMiD) used in cancer therapy, lowers TNF-α generation and thus has potent anti-inflammatory actions. Well-tolerated analogs may provide a stroke treatment and allow evaluation of the role of neuroinflammation in the ischemic brain. (2) Methods: Two novel pomalidomide derivatives, 3,6'-dithiopomalidomide (3,6'-DP) and 1,6'-dithiopomalidomide (1,6'-DP), were evaluated alongside pomalidomide in a rat middle cerebral artery occlusion (MCAo) stroke model, and their anti-inflammatory actions were characterized. (3) Results: Post-MCAo administration of all drugs lowered pro-inflammatory TNF-α and IL1-β levels, and reduced stroke-induced postural asymmetry and infarct size. Whereas 3,6'- and 1,6'-DP, like pomalidomide, potently bound to cereblon in cellular studies, 3,6'-DP did not lower Ikaros, Aiolos or SALL4 levels-critical intermediates mediating the anticancer/teratogenic actions of pomalidomide and IMiDs. 3,6'-DP and 1,6'-DP lacked activity in mammalian chromosome aberration, AMES and hERG channel assays -critical FDA regulatory tests. Finally, 3,6'- and 1,6'-DP mitigated inflammation across rat primary dopaminergic neuron and microglia mixed cultures challenged with α-synuclein and mouse LPS-challenged RAW 264.7 cells. (4) Conclusion: Neuroinflammation mediated via TNF-α plays a key role in stroke outcome, and 3,6'-DP and 1,6'-DP may prove valuable as stroke therapies and thus warrant further preclinical development.

Detection of Tumor-specific DNA Methylation Markers in the Blood of Patients with Pituitary Neuroendocrine Tumors

Background

DNA methylation abnormalities are pervasive in pituitary neuroendocrine tumors (PitNETs). The feasibility to detect methylome alterations in circulating cell-free DNA (cfDNA) has been reported for several central nervous system (CNS) tumors but not across PitNETs. The aim of the study was to use the liquid biopsy (LB) approach to detect PitNET-specific methylation signatures to differentiate these tumors from other sellar diseases.

Methods

We profiled the cfDNA methylome (EPIC array) of 59 serum and 41 plasma LB specimens from patients with PitNETs and other CNS diseases (sellar tumors and other pituitary non-neoplastic diseases, lower-grade gliomas, and skull-base meningiomas) or nontumor conditions, grouped as non-PitNET.

Results

Our results indicated that despite quantitative and qualitative differences between serum and plasma cfDNA composition, both sources of LB showed that patients with PitNETs presented a distinct methylome landscape compared to non-PitNETs. In addition, LB methylomes captured epigenetic features reported in PitNET tissue and provided information about cell-type composition. Using LB-derived PitNETs-specific signatures as input to develop machine-learning predictive models, we generated scores that distinguished PitNETs from non-PitNETs conditions, including sellar tumor and non-neoplastic pituitary diseases, with accuracies above ~93% in independent cohort sets.

Conclusions

Our results underpin the potential application of methylation-based LB profiling as a noninvasive approach to identify clinically relevant epigenetic markers to diagnose and potentially impact the prognostication and management of patients with PitNETs.

Neurosurgery residency and fellowship education in the United States: 2 decades of system development by the One Neurosurgery Summit organizations

The purpose of this report is to chronicle a 2-decade period of educational innovation and improvement, as well as governance reform, across the specialty of neurological surgery. Neurological surgery educational and professional governance systems have evolved substantially over the past 2 decades with the goal of improving training outcomes, patient safety, and the quality of US neurosurgical care. Innovations during this period have included the following: creating a consensus national curriculum; standardizing the length and structure of neurosurgical training; introducing educational outcomes milestones and required case minimums; establishing national skills, safety, and professionalism courses; systematically accrediting subspecialty fellowships; expanding professional development for educators; promoting training in research; and coordinating policy and strategy through the cooperation of national stakeholder organizations. A series of education summits held between 2007 and 2009 restructured some aspects of neurosurgical residency training. Since 2010, ongoing meetings of the One Neurosurgery Summit have provided strategic coordination for specialty definition, neurosurgical education, public policy, and governance. The Summit now includes leadership representatives from the Society of Neurological Surgeons, the American Association of Neurological Surgeons, the Congress of Neurological Surgeons, the American Board of Neurological Surgery, the Review Committee for Neurological Surgery of the Accreditation Council for Graduate Medical Education, the American Academy of Neurological Surgery, and the AANS/CNS Joint Washington Committee. Together, these organizations have increased the effectiveness and efficiency of the specialty of neurosurgery in advancing educational best practices, aligning policymaking, and coordinating strategic planning in order to meet the highest standards of professionalism and promote public health.

Drug Repurposing in the Treatment of Traumatic Brain Injury

Traumatic brain injury (TBI) is the most common cause of morbidity among trauma patients; however, an effective pharmacological treatment has not yet been approved. Individuals with TBI are at greater risk of developing neurological illnesses such as Alzheimer's disease (AD) and Parkinson's disease (PD). The approval process for treatments can be accelerated by repurposing known drugs to treat the growing number of patients with TBI. This review focuses on the repurposing of N-acetyl cysteine (NAC), a drug currently approved to treat hepatotoxic overdose of acetaminophen. NAC also has antioxidant and anti-inflammatory properties that may be suitable for use in therapeutic treatments for TBI. Minocycline (MINO), a tetracycline antibiotic, has been shown to be effective in combination with NAC in preventing oligodendrocyte damage. (-)-phenserine (PHEN), an anti-acetylcholinesterase agent with additional non-cholinergic neuroprotective/neurotrophic properties initially developed to treat AD, has demonstrated efficacy in treating TBI. Recent literature indicates that NAC, MINO, and PHEN may serve as worthwhile repositioned therapeutics in treating TBI.

Back to the future: surgical rehearsal platform technology as a means to improve surgeon-patient alliance, patient satisfaction, and resident experience

OBJECTIVE

Informed consent, when performed appropriately, serves many roles beyond simply obtaining the prerequisite medicolegal paperwork to perform a surgery. Prior studies have suggested that patient understanding is poor when verbal communication is the sole means of education. Virtual reality platforms have proven effective in enhancing medical education. No studies exist that have demonstrated the utility of virtual reality-facilitated informed consent (VR-IC) in improving the physician-patient alliance. The aim of this study was to determine the utility of VR-IC among patients providing consent for surgery and the impact of this educational and information technology-based strategy on enhancing the physician-patient alliance, patient satisfaction, and resident-physician perception of the consent process.

METHODS

Prospective, single-site, pre- and postconsent surveys were administered to assess patient and resident perception of informed consent performed with the aid of VR-IC at a large tertiary academic medical center in the US. Participants were adult patients (n = 50) undergoing elective surgery for tumor resection and neurosurgical residents (n = 19) who obtained patient informed consent for these surgical procedures. Outcome measures included scores on the Patient-Doctor Relationship Questionnaire (PDRQ-9), the modified Satisfaction with Simulation Experience Scale, and the Maslach Burnout Inventory. Patient pre- and postconsent data were recorded in real time using a secure online research data platform (REDCap).

RESULTS

A total of 48 patients and 2 family members provided consent using VR-IC and completed the surveys pre- and postconsent; 47.9% of patients were women. The mean patient age was 57.5 years. There was a statistically significant improvement from pre- to post-VR-IC consent in patient satisfaction scores. Measures of patient-physician alliance, trust, and understanding of their illness all increased. Among the 19 trainees, perceived comfort and preparedness with the informed consent process significantly improved.

CONCLUSIONS

VR-IC led to improved patient satisfaction, patient-physician alliance, and patient understanding of their illness as measured by the PDRQ-9. Using VR-IC contributed to residents' increased comfort in the consent-gathering process and handling patient questions. In an era in which satisfaction scores are directly linked with hospital and service-line outcomes and reimbursement, positive results from VR-IC may augment physician and hospital satisfaction scores in addition to increasing measures of trust between physicians and patients.

Intratumoral Rathke's Cleft Cyst Remnants Within Craniopharyngioma, Pituitary Adenoma, Suprasellar Dermoid, and Epidermoid Cysts: A Ubiquitous Signature of Ectodermal Lineage or a Transitional Entity?

BACKGROUND

The authors present cystic epithelial masses in the suprasellar region which on histopathology revealed 4 mixed tumors having simple cuboidal epithelium of Rathke's Cleft Cyst (RCC) elements trapped within pituitary adenoma, epidermoid cyst, dermoid cyst, and papillary craniopharyngioma respectively.

OBJECTIVE

To highlight the developmental theory of ectodermal continuum in the realm of suprasellar epithelial cystic lesions and examines the cardinal aspects that distinguish RCC from its confounder, ciliary craniopharyngioma.

METHODS

The authors performed a medical chart review on 4 patients who had coexisting RCC with craniopharyngioma, pituitary adenoma, suprasellar dermoid, and epidermoid cysts.

RESULTS

This series of unique suprasellar lesions elucidate the spectrum of cases from Rathke's cyst to other suprasellar epithelial cysts including a recently identified clinical entity called ciliary craniopharyngioma, which authors feel is a misnomer. The authors also report the first case of ruptured dermoid cyst admixed with elements of Rathke's cyst elements and xanthogranuloma in neurosurgical literature.

CONCLUSION

We propose that the new entity of ciliary craniopharyngioma could be just another variant of RCC elements nested within a typical papillary or adamantinomatous lesion. Further study is warranted to understand the implications of natural history with tumors containing RCC elements.

Impact of Resident Involvement in Neurosurgery: An American College of Surgeons' National Surgical Quality Improvement Program Database Analysis of 33,977 Patients

OBJECTIVE

There is conflicting and limited literature on the effect of intraoperative resident involvement on surgical outcomes. Our study assessed effects of resident involvement on outcomes in patients undergoing neurosurgery.

METHODS

We identified 33,977 adult neurosurgical cases from 374 hospitals in the 2006-2012 National Surgical Quality Improvement Program, a prospectively collected national database with established reproducibility and validity. Outcomes were compared according to resident involvement before and after 1:1 matching on procedure and perioperative risk factors.

RESULTS

Resident involvement was documented in 13,654 cases. We matched 10,170 resident-involved cases with 10,170 attending-alone. In the matched sample, resident involvement was associated with increased surgery duration (average, 34 minutes) and slight increases in odds for prolonged hospital stay (odds ratio, 1.2; 95% confidence interval [CI], 1.2-1.3) and complications (odds ratio, 1.2; 95% CI, 1.1-1.3) including infections (odds ratio, 1.4; 95% CI, 1.2-1.7). Increased risk for infections persisted after controlling for surgery duration (odds ratio, 1.3; 95% CI, 1.1-1.5). The majority of cases were spine surgeries, and resident involvement was not associated with morbidity or mortality for malignant tumor and aneurysm patients. Training level of residents was not associated with differences in outcomes.

CONCLUSION

Resident involvement was more common in sicker patients undergoing complex procedures, consistent with academic centers undertaking more complex cases. After controlling for patient and intraoperative characteristics, resident involvement in neurosurgical cases continued to be associated with longer surgical duration and slightly higher infection rates. Longer surgery duration did not account for differences in infection rates.

The Value of Perioperative Levels of ACTH, DHEA, and DHEA-S and Tumor Size in Predicting Recurrence of Cushing Disease

CONTEXT AND OBJECTIVES

Despite the development of hypocortisolemia after corticotroph surgical adenomectomy, 15% to 20% patients have recurrence of Cushing disease (CD). In this study, we investigated the effect of tumor size and the value of perioperative assessment of corticotropin (ACTH) and adrenal steroid levels in predicting recurrence.

DESIGN

Perioperatively, no glucocorticoids were administered until the serum cortisol was ≤3 μg/dL. Blood samples were obtained before and repeatedly after adenomectomy in 79 patients with CD. Of these, 66 had a nadir serum cortisol of ≤3.0 μg/dL and clinical and biochemical remissions. During a median follow-up of 131 months, 11 of 66 had disease recurrence (REC), whereas 55 of 66 did not (NO-REC).

RESULTS

Preoperative hormone levels in the REC and NO-REC groups were similar. After adenomectomy, a brief and similar increase in ACTH, cortisol, and dehydroepiandrosterone (DHEA) levels was observed in both groups followed by gradual decline in those levels. Although REC and NO-REC patients had similar cortisol levels (3.4 ± 1.7 μg/dL vs 2.9 ± 2.2 μg/dL) at the 36th postoperative hour, their respective ACTH (33 ± 7.1 ng/L vs 12.1 ± 5.4 ng/L; P < 0.0001), DHEA (3.8 ± 1.7 ng/mL vs 1.2 ± 1.1 ng/mL; P = 0.005), and dehydroepiandrosterone sulphate (DHEA-S) (143.9 ± 45.2 μg/dL vs 48.9 ± 38.2 μg/dL; P < 0.0001) were higher. At nadir hypocortisolemia, perioperative ACTH levels were >20 in all REC patients and <20 ng/L in the NO-REC group. Patients with REC had larger tumors than those with NO-REC.

CONCLUSION

Recurrent CD is characterized by persistent perioperative ACTH secretion after adenomectomy. Higher perioperative levels of ACTH, DHEA, and DHEA-S are highly predictive of future disease recurrence, particularly in those with profound hypocortisolemia.

The impact of peri-operative dexamethasone administration on the normal hypothalamic pituitary adrenal response to major surgical procedures

BACKGROUND

Surgical procedures are associated with activation of the hypothalamic-pituitary-adrenal axis (HPA). Studies examining HPA dynamics peri-operatively are limited and the modulating influence of peri-operatively administered glucocorticoids on that is not well established. This investigation examined alterations in HPA function and the impact of dexamethasone (DEX) administration during the peri-operative period.

METHODS

We examined HPA function in 297 patients with normal function who had surgical procedures including pituitary mass resection (n = 191), craniotomy (n = 17) and other thoracic/ abdominal/ pelvic surgeries (n = 89). HPA function was assessed by frequent measurements of parameters defining adrenal function: ACTH, cortisol, DHEA and DHEA-S levels for 48 h. DEX was administered as a single dose (2-10 mg) to 30 and as multiple doses (12-36 mg) to 21 patients. The data of DEX-treated subjects within each group were similar and were combined together.

RESULTS

Pre-operative data were similar for patients having different surgical procedures. Without DEX exposure, ACTH increased to 225 ± 100 ng/L at 2-4 h and gradually declined to baseline values by 36 h while cortisol levels peaked (39.2 ± 13.2 ug/dL) at 6-8 h declining gradually thereafter. Cortisol rise was paralleled by an equimolar increase in DHEA and a subsequent increase in DHEA-S levels. Single doses of DEX did not influence ACTH or cortisol secretion but suppressed the expected rise in DHEA and DHEA-S levels. Multiple doses of DEX suppressed ACTH and cortisol after the 15th postoperative hour and completely blocked the expected rise in DHEA and DHEA-S levels.

CONCLUSIONS

The data provide a detailed overview of HPA function in a large number of subjects who had major surgical procedures. Single and large doses of DEX did not suppress ACTH or cortisol secretion but suppressed adrenal androgen secretion. It took multiple doses of DEX to partially suppress ACTH and cortisol secretion in the peri-operative period.

Utilization of sinus stents as a novel approach for benign cystic lesions of the sella

Steroid-releasing sinus stents have emerged as a safe and effective tool in endoscopic sinus surgery. In this case report, we present two patients with recurrent cystic sellar masses. Transsphenoidal approach was used to access the sella. Following resection and drainage of the cystic pathology, a Propel (Menlo Park, CA) stent was placed through the corridor of the resection site to stent the cavity open. This is the first report where a steroid-releasing sinus stent was used in the treatment of a sellar lesion. It supports that this technology is safe and effective for use in skull base surgery.

Perioperative hypothalamic pituitary adrenal function in patients with silent corticotroph adenomas

BACKGROUND

Silent corticotroph adenomas (SCAs) are characterized by strong ACTH immunostaining without clinical manifestations of hypercortisolism. Patients with SCAs often present with mechanical symptoms related to tumor growth. This study investigates the hypothalamic pituitary adrenal axis (HPA) characteristics after adenomectomy in patients with SCAs.

METHODS

Biochemical parameters of HPA function were monitored frequently after surgical resection of non-functioning macroadenomas. Levels of ACTH, cortisol, DHEA and DHEA-S were measured frequently for 48 h after adenomectomy. HPA data of patients with SCAs (n = 38) were compared to others (Controls) with non-secreting, ACTH-negative immunostaining adenomas of similar age and gender distribution (n = 182) who had adenomectomy.

RESULT

Plasma ACTH increased (P < 0.0001) equally in patients with SCA and controls reaching a peak at 3 h (238 ± 123 vs. 233 ± 96 ng/L, respectively) after extubation declining thereafter to baseline values 24-36 h. Similarly, serum cortisol levels increased (P < 0.0001) equally in both groups reaching a maximum at 7 h (36.8 ± 13.9 vs. 39.3 ± 13.3 ug/dL). Serum DHEA also increased (P < 0.001) equally in both groups in parallel to the rise in serum cortisol. Serum DHEA-S levels similarly increased (P < 0.001) from their respective baseline (105.9 ± 67.5 and 106.5 ± 58.7 ug/dL) reaching their peak (154.5 ± 69.5 and 153.5 ± 68.6 ug/dL; respectively) at 15 h after extubation. None of the patients acquired any hormone deficits.

CONCLUSIONS

Under the maximal stimulation of the peri-operative stress, HPA function in patients with SCA behaved in an identical manner to others with ACTH-negative macroadenomas. Thus, despite the strong ACTH-positive immunostaining of these tumors, SCAs are truly non- functional.

Mature salivary gland rests within sonic hedgehog-positive medulloblastoma: case report and insights into the molecular genetics and embryopathology of ectopic intracranial salivary gland analogs

Intracranial ectopic salivary gland rests within dural-based lesions are reported very infrequently in the literature. The authors report the unique case of a 12-year-old boy with a cerebellar medulloblastoma positive for sonic hedgehog (Shh) that contained intraaxial mature ectopic salivary gland rests. The patient underwent clinical and radiological monitoring postoperatively, until he died of disseminated disease. An autopsy showed no evidence of salivary glands within disseminated lesions. The intraaxial presence of salivary gland rests and concomitant Shh positivity of the described tumor point to a disorder in differentiation as opposed to ectopic developmental foci, which are uniformly dural based in the described literature. The authors demonstrate the characteristic "papilionaceous" appearance of the salivary glands with mucicarmine stain and highlight the role of Shh signaling in explaining the intraaxial presence of seromucous gland analogs. This article reports the first intraaxial posterior fossa tumor with heterotopic salivary gland rests, and it provides molecular and embryopathological insights into the development of these lesions.

Use of a surgical rehearsal platform and improvement in aneurysm clipping measures: results of a prospective, randomized trial

OBJECTIVE The field of neurosurgery is constantly undergoing improvements and advances, both in technique and technology. Cerebrovascular neurosurgery is no exception, with endovascular treatments changing the treatment paradigm. Clipping of aneurysms is still necessary, however, and advances are still being made to improve patient outcomes within the microsurgical treatment of aneurysms. Surgical rehearsal platforms are surgical simulators that offer the opportunity to rehearse a procedure prior to entering the operative suite. This study is designed to determine whether use of a surgical rehearsal platform in aneurysm surgery is helpful in decreasing aneurysm dissection time and clip manipulation of the aneurysm. METHODS The authors conducted a blinded, prospective, randomized study comparing key effort and time variables in aneurysm clip ligation surgery with and without preoperative use of the SuRgical Planner (SRP) surgical rehearsal platform. Initially, 40 patients were randomly assigned to either of two groups: one in which surgery was performed after use of the SRP (SRP group) and one in which surgery was performed without use of the SRP (control group). All operations were videotaped. After exclusion of 6 patients from the SRP group and 9 from the control group, a total of 25 surgical cases were analyzed by a reviewer blinded to group assignment. The videos were analyzed for total microsurgical time, number of clips used, and number of clip placement attempts. Means and standard deviations (SDs) were calculated and compared between groups. RESULTS The mean (± SD) amount of operative time per clip used was 920 ± 770 seconds in the SRP group and 1294 ± 678 seconds in the control group (p = 0.05). In addition, the mean values for the number of clip attempts, total operative time, ratio of clip attempts to clips used, and time per clip attempt were all lower in the SRP group, although the between-group differences were not statistically significant. CONCLUSIONS Preoperative rehearsal with SRP increased efficiency and safety in aneurysm microsurgery as demonstrated by the statistically significant improvement in time per clip used. Although the rest of the outcomes did not demonstrate statistically significant between-group differences, the fact that the SRP group showed improvement in mean values for all measures studied suggests that preoperative rehearsal may increase the efficiency and safety of aneurysm microsurgery. Future studies aimed at improving patient outcome and safety during surgical clipping of aneurysms will be needed to keep pace with the quickly advancing endovascular field.

Postoperative sellar hematoma after pituitary surgery: clinical and biochemical characteristics

BACKGROUND

Postoperative sellar hematoma can develop following surgery for pituitary tumors and other sellar masses such a Rathke's cleft cyst (RCC) due to continued blood oozing. Though often mild sellar hematoma can create mass effects that might impair pituitary function.

AIM

This study summarizes the clinical and biochemical characteristics of sellar hematoma and explores the potential mechanisms for the associated hypopituitarism.

PATIENTS AND METHODS

Sellar hematoma was suspected clinically (worsening headaches, visual impairment, and mental status alterations) and confirmed radiographically in 23 patients (18/279 with macroadenomas and in 5/92 with RCC). Postoperatively, patients were monitored without glucocorticoid therapy and all had appropriately normal HPA function before sellar hematoma diagnosis.

RESULTS

The demographics of patients who had sellar hematoma were similar to those who did not. Biochemical changes at diagnosis included decreased plasma ACTH and its dependent steroids (cortisol, DHEA, and DHEA-S), concomitant mild hyperprolactinemia, and mild hyponatremia (P < 0.005 for all parameters). Treatment with glucocorticoids resulted in rapid clinical improvement in most patients. Glucocorticoid therapy was discontinued within 2 weeks and re-testing thereafter showed normal HPA function in 16/23. None of the patients without sellar hematoma had worsening in pituitary function, visual, or neurological symptoms.

CONCLUSIONS

When large, sellar hematoma can lead to mass effect that causes headaches, visual symptoms, and acute and often reversible hypopituitarism manifesting initially as impaired HPA function. Rapid resolution is observed in most patients with glucocorticoid administration The rapid onset and reversibility of hypopituitarism associated with mild hyperprolactinemia suggest that compression of pituitary stalk/ portal vessels is likely the dominant mechanism of pituitary dysfunction in this setting.

The Recent Revolution in the Design and Manufacture of Cranial Implants: Modern Advancements and Future Directions

Large format (i.e., >25 cm) cranioplasty is a challenging procedure not only from a cosmesis standpoint, but also in terms of ensuring that the patient's brain will be well-protected from direct trauma. Until recently, when a patient's own cranial flap was unavailable, these goals were unattainable. Recent advances in implant computer-aided design and 3-dimensional (3-D) printing are leveraging other advances in regenerative medicine. It is now possible to 3-D-print patient-specific implants from a variety of polymer, ceramic, or metal components. A skull template may be used to design the external shape of an implant that will become well integrated in the skull, while also providing beneficial distribution of mechanical force in the event of trauma. Furthermore, an internal pore geometry can be utilized to facilitate the seeding of banked allograft cells. Implants may be cultured in a bioreactor along with recombinant growth factors to produce implants coated with bone progenitor cells and extracellular matrix that appear to the body as a graft, albeit a tissue-engineered graft. The growth factors would be left behind in the bioreactor and the graft would resorb as new host bone invades the space and is remodeled into strong bone. As we describe in this review, such advancements will lead to optimal replacement of cranial defects that are both patient-specific and regenerative.

Pitfalls in the diagnosis and management of Cushing's syndrome

Despite many recent advances, the management of patients with Cushing's disease continues to be challenging. Cushing's syndrome is a complex metabolic disorder that is a result of excess glucocorticoids. Excluding the exogenous causes, adrenocorticotropic hormone-secreting pituitary adenomas account for nearly 70% of all cases of Cushing's syndrome. The suspicion, diagnosis, and differential diagnosis require a logical systematic approach with attention paid to key details at each investigational step. A diagnosis of endogenous Cushing's syndrome is usually suspected in patients with clinical symptoms and confirmed by using multiple biochemical tests. Each of the biochemical tests used to establish the diagnosis has limitations that need to be considered for proper interpretation. Although some tests determine the total daily urinary excretion of cortisol, many others rely on measurements of serum cortisol at baseline and after stimulation (e.g., after corticotropin-releasing hormone) or suppression (e.g., dexamethasone) with agents that influence the hypothalamic-pituitary-adrenal axis. Other tests (e.g., measurements of late-night salivary cortisol concentration) rely on alterations in the diurnal rhythm of cortisol secretion. Because more than 90% of the cortisol in the circulation is protein bound, any alteration in the binding proteins (transcortin and albumin) will automatically influence the measured level and confound the interpretation of stimulation and suppression data, which are the basis for establishing the diagnosis of Cushing's syndrome. Although measuring late-night salivary cortisol seems to be an excellent initial test for hypercortisolism, it may be confounded by poor sampling methods and contamination. Measurements of 24-hour urinary free-cortisol excretion could be misleading in the presence of some pathological and physiological conditions. Dexamethasone suppression tests can be affected by illnesses that alter the absorption of the drug (e.g., malabsorption, celiac disease) and by the concurrent use of medications that interfere with its metabolism (e.g., inducers and inhibitors of the P450 enzyme system). In this review, the authors aim to review the pitfalls commonly encountered in the workup of patients suspected to have hypercortisolism. The optimal diagnosis and therapy for patients with Cushing's disease require the thorough and close coordination and involvement of all members of the management team.

Postnatal Pancraniosynostosis in a Patient With Infantile Hypophosphatasia

Hypophosphatasia is a rare metabolic bone disorder that predisposes patients to craniosynostosis. Typically, patients born with hypophosphatasia will exhibit fused cranial sutures at birth. This is the first reported case of delayed onset of pancraniosynostosis in a patient with infantile hypophosphatasia. The severity of onset and delayed presentation in this patient are of interest and should give pause to those care providers who treat and evaluate patients with hypophosphatasia.

Risks associated with preoperative anemia and perioperative blood transfusion in open surgery for intracranial aneurysms

OBJECT

Preoperative anemia may be treated with a blood transfusion. Both are associated with adverse outcomes in various surgical procedures, but this has not been clearly elucidated in surgery for cerebral aneurysms. In this study the authors assessed the association of preoperative anemia and perioperative blood transfusion, separately, on 30-day morbidity and mortality in patients undergoing open surgery for ruptured and unruptured intracranial aneurysms.

METHODS

The authors identified 668 cases (including 400 unruptured and 268 unruptured intracranial aneurysms) of open surgery for treatment of intracranial aneurysms in the 2006-2012 National Surgical Quality Improvement Program, a validated and reproducible prospective clinical database. Anemia was defined as a hematocrit level less than 39% in males and less than 36% in females. Perioperative transfusion was defined as at least 1 unit of packed or whole red blood cells given at any point between the start of surgery to 72 hours postoperatively. The authors separately compared surgical outcome between patients with (n = 198) versus without (n = 470) anemia, and those who underwent (n = 78) versus those who did not receive (n = 521) a transfusion, using a 1:1 match on propensity score.

RESULTS

In the matched cohorts, all observed covariates were comparable between anemic (n = 147) versus nonanemic (n = 147) and between transfused (n = 67) versus nontransfused patients (n = 67). Anemia was independently associated with prolonged hospital length of stay (LOS; odds ratio [OR] 2.5, 95% confidence interval [CI] 1.4-4.5), perioperative complications (OR 1.9, 95% CI 1.1-3.1), and return to the operating room (OR 2.1, 95% CI 1.1-4.5). Transfusion was also independently associated with perioperative complications (OR 2.4, 95% CI 1.1-5.3).

CONCLUSIONS

Preoperative anemia and transfusion are each independent risk factors for perioperative complications in patients undergoing surgery for cerebral aneurysms. Perioperative anemia is also associated with prolonged hospital LOS and 30-day return to the operating room.

Clinical and biochemical characteristic features of metastatic cancer to the sella turcica: an analytical review

BACKGROUND AND OBJECTIVES

Sellar metastasis is uncommon and poorly characterized as published data include small series of subjects. This study's goal is to identify unique features that differentiate this entity from other sellar masses such as pituitary macroadenomas.

METHODS

Published cases of pathologically-confirmed sellar metastasis along with our experience in such patients over a 6-years period were reviewed (total = 129). As a control group, we reviewed similar data on 55 patients with pituitary macroadenomas managed over the same time-period. Presenting symptoms, pituitary dysfunction were analyzed using univariate, multivariate and receiver operating characteristic (ROC) analyses.

RESULTS

Sellar metastasis has equal gender distribution with a median patient-age of 56 years. The most common primary malignancy was breast cancer (29%) in women and lung cancer (30%) in men. Sellar metastasis was the first manifestation of cancer in over 40% of patients. Common presenting symptoms included headaches, visual field deficits, abnormal eye motility and diabetes insipidus. These symptoms were less frequent among patients with pituitary macroadenomas. Univariate regression analyses showed that headaches, abnormal eye motility, visual field deficits and diabetes insipidus were each predictive of metastatic disease. ROC analysis combining all 4 features revealed an AUC of 0.953 with a sensitivity of 0.818 and a specificity of 0.935. Using the multivariate regression, abnormal eye motility and/or diabetes insipidus independently predicted metastatic disease.

CONCLUSIONS

Sellar metastasis should be suspected in patients presenting with sellar masses, abnormal eye motility and/or diabetes insipidus even those without known malignancy since pituitary metastasis can often be the first manifestation of cancer.

Histologically Proven Radiation-Induced Brainstem Glioma 93 Months After External Beam Radiotherapy for Pituitary Macroadenoma: Radiation Treatment Dose and Volume Correlation

Patient is a 29-year-old with a history of recurrent growth hormone-secreting pituitary macroadenoma diagnosed 12 years prior to presentation. Eight years prior to current presentation, the patient underwent re-resection and received 50.4 Gy external beam radiotherapy (EBRT) in 28 fractions of 1.8 Gy each. Serial postradiation MRIs demonstrated regression in pituitary tumor size. Patient presented with new headaches 7.5 years after completing EBRT. Brain MRI demonstrated new FLAIR hyperintensity and contrast enhancement within the pons and medulla, corresponding to the 36 Gy isodose line of each radiation dose fraction. Differential diagnosis included radiation necrosis and radiation-induced glioma (RIG). The patient's neurologic exam worsened over the following 4 months. MRI showed progressive increase in mass effect, extent of FLAIR hyperintensity, and contrast enhancement in the brainstem. Stereotactic-assisted biopsy showed infiltrating astrocytoma with moderate atypia. A PubMed search showed this is the first case of histologically verified brainstem RIG correlated with 3-dimensional conformational radiation therapy dose and volume planning following EBRT for a pituitary adenoma. The rare occurrence of brainstem RIG after radiation therapy for pituitary tumor supports the need for long-term imaging monitoring of such patients.

Trends in central nervous system tumor incidence relative to other common cancers in adults, adolescents, and children in the United States, 2000 to 2010

BACKGROUND

Time trends in cancer incidence rates (IR) are important to measure the changing burden of cancer on a population over time. The overall IR of cancer in the United States is declining. Although central nervous system tumors (CNST) are rare, they contribute disproportionately to mortality and morbidity. In this analysis, the authors examined trends in the incidence of the most common cancers and CNST between 2000 and 2010.

METHODS

The current analysis used data from the United States Cancer Statistics publication and the Central Brain Tumor Registry of the United States. Age-adjusted IR per 100,000 population with 95% confidence intervals and the annual percent change (APC) with 95% confidence intervals were calculated for selected common cancers and CNST overall and by age, sex, race/ethnicity, selected histologies, and malignancy status.

RESULTS

In adults, there were significant decreases in colon (2000-2010: APC, -3.1), breast (2000-2010: APC, -0.8), lung (2000-2010: APC, -1.1), and prostate (2000-2010: APC, -2.4) cancer as well as malignant CNST (2008-2010: APC, -3.1), but a significant increase was noted in nonmalignant CNST (2004-2010: APC, 2.7). In adolescents, there were significant increases in malignant CNST (2000-2008: APC, 1.0) and nonmalignant CNST (2004-2010: APC, 3.9). In children, there were significant increases in acute lymphocytic leukemia (2000-2010: APC, 1.0), non-Hodgkin lymphoma (2000-2010: APC, 0.6), and malignant CNST (2000-2010: APC, 0.6).

CONCLUSIONS

Surveillance of IR trends is an important way to measure the changing public health and economic burden of cancer. In the current study, there were significant decreases noted in the incidence of adult cancer, whereas adolescent and childhood cancer IR were either stable or increasing.

Petroclival meningiomas: an update on surgical approaches, decision making, and treatment results

OBJECT

Petroclival meningiomas remain a formidable challenge for neurosurgeons because of their location deep within the skull base and proximity to eloquent neurovascular structures. Various skull base approaches have been used in their treatment, and deciding which is the optimal one remains controversial. Attempts at achieving gross- or near-total resections are associated with an increased rate of morbidity and mortality. As adjunctive treatment options such as stereotactic radiosurgery have been developed and become widely available, there has been a trend toward accepting subtotal resections in an effort to minimize neurological morbidity. This paper reviews a recent series of patients with petroclival meningiomas and highlights current management trends and important considerations useful in surgical decision making.

METHODS

The records of patients with large (> 3 cm) petroclival meningiomas surgically treated by the senior author over the past 5 years were reviewed. The clinical results are presented as examples of the surgical approaches available for approaching these tumors, and treatment options are reviewed.

RESULTS

Of 196 meningiomas surgically treated during the study period, 8 lesions in 8 patients met the study criteria. Overall clinical results were excellent, with no death or major morbidity. Intracranial gross- or near-total resection (Simpson Grade 1, 2, or 3) was achieved in 5 patients (67%). New cranial nerve deficits occurred in 3 patients (37%) and were more common in patients in whom a subtotal resection was performed (2 of 3 cases). A variety of surgical approaches were used. Important considerations determining the best approach include the location of the tumor relative to the internal auditory canal, the presence of preoperative hearing loss, and the location of the tumor relative to the tentorium.

CONCLUSIONS

Achieving gross- or near-total resections of large petroclival meningiomas remains achievable and should be the primary goal of surgical treatment. A retrosigmoid craniotomy remains a workhorse surgical approach for most petroclival tumors of any size. Tumors that are medial to the internal auditory canal and span both middle and posterior cranial fossae are often best treated with a combined transpetrosal approach, which is especially true if there is a preoperative hearing deficit.

Peritumoral brain edema in intracranial meningiomas: the emergence of vascular endothelial growth factor-directed therapy

Meningioma is the second most common type of adult intracranial neoplasm. A substantial subset of patients present with peritumoral brain edema (PTBE), which can cause significant morbidity via mass effect, complicate surgical management, and impact the safety of stereotactic radiosurgery. Recent studies suggest a close relationship between vascular endothelial growth factor-A (VEGF-A) expression and PTBE development in meningiomas. The authors performed a systematic review of the literature on the pathogenesis of PTBE in meningiomas, the effectiveness of steroid therapy, the role played by VEGF-A, and the current clinical evidence for antiangiogenic therapy to treat peritumoral brain edema. Mounting evidence suggests VEGF-A is secreted directly by meningioma cells to induce angiogenesis and edemagenesis of tumoral as well as peritumoral brain tissue. The VEGF-A cascade results in recruitment of cerebral-pial vessels and disruption of the tumor-brain barrier, which appear to be requisite for VEGF-A to have an edemagenic effect. Results of preliminary clinical studies suggest VEGF-directed therapy has modest activity against recurrent and progressive meningioma growth but can alleviate PTBE in some patients. A comprehensive understanding of the VEGF-A pathway and its modulators may hold the key to an effective therapeutic approach to treating PTBE associated with meningiomas. Further clinical trials with larger patient cohorts and longer follow-up periods are warranted to confirm the efficacy of VEGF-directed therapy.

Descriptive epidemiology of pituitary tumors in the United States, 2004-2009

OBJECT

Pituitary tumors are abnormal growths that develop in the pituitary gland. The Central Brain Tumor Registry of the United States (CBTRUS) contains the largest aggregation of population-based data on the incidence of primary CNS tumors in the US. These data were used to determine the incidence of tumors of the pituitary and associated trends between 2004 and 2009.

METHODS

Using incidence data from 49 population-based state cancer registries, 2004-2009, age-adjusted incidence rates per 100,000 population for pituitary tumors with ICD-O-3 (International Classification of Diseases for Oncology, Third Edition) histology codes 8040, 8140, 8146, 8246, 8260, 8270, 8271, 8272, 8280, 8281, 8290, 8300, 8310, 8323, 9492 (site C75.1 only), and 9582 were calculated overall and by patient sex, race, Hispanic ethnicity, and age at diagnosis. Corresponding annual percent change (APC) scores and 95% confidence intervals were also calculated using Joinpoint to characterize trends in incidence rates over time. Diagnostic confirmation by subregion of the US was also examined. The overall annual incidence rate increased from 2.52 (95% CI 2.46-2.58) in 2004 to 3.13 (95% CI 3.07-3.20) in 2009. Associated time trend yielded an APC of 4.25% (95% CI 2.91%-5.61%). When stratifying by patient sex, the annual incidence rate increased from 2.42 (95% CI 2.33-2.50) to 2.94 (95% CI 2.85-3.03) in men and 2.70 (95% CI 2.62-2.79) to 3.40 (95% CI 3.31-3.49) in women, with APCs of 4.35% (95% CI 3.21%-5.51%) and 4.34% (95% CI 2.23%-6.49%), respectively. When stratifying by race, the annual incidence rate increased from 2.31 (95% CI 2.25-2.37) to 2.81 (95% CI 2.74-2.88) in whites, 3.99 (95% CI 3.77-4.23) to 5.31 (95% CI 5.06-5.56) in blacks, 1.77 (95% CI 1.26-2.42) to 2.52 (95% CI 1.96-3.19) in American Indians or Alaska Natives, and 1.86 (95% CI 1.62-2.13) to 2.03 (95% CI 1.80-2.28) in Asians or Pacific Islanders, with APCs of 3.91% (95% CI 2.88%-4.95%), 5.25% (95% CI 3.19%-7.36%), 5.31% (95% CI -0.11% to 11.03%), and 2.40% (95% CI -3.20% to 8.31%), respectively. When stratifying by Hispanic ethnicity, the annual incidence rate increased from 2.46 (95% CI 2.40-2.52) to 3.03 (95% CI 2.97-3.10) in non-Hispanics and 3.12 (95% CI 2.91-3.34) to 4.01 (95% CI 3.80-4.24) in Hispanics, with APCs of 4.15% (95% CI 2.67%-5.65%) and 5.01% (95% CI 4.42%-5.60%), respectively. When stratifying by age at diagnosis, the incidence of pituitary tumor was highest for those 65-74 years old and lowest for those 15-24 years old, with corresponding overall age-adjusted incidence rates of 6.39 (95% CI 6.24-6.54) and 1.56 (95% CI 1.51-1.61), respectively.

CONCLUSIONS

In this large patient cohort, the incidence of pituitary tumors reported between 2004 and 2009 was found to increase. Possible explanations for this increase include changes in documentation, changes in the diagnosis and registration of these tumors, improved diagnostics, improved data collection, increased awareness of pituitary diseases among physicians and the public, longer life expectancies, and/or an actual increase in the incidence of these tumors in the US population.

Impact of age on 30-day postoperative outcome of surgery for ruptured and unruptured intracranial aneurysms

OBJECTIVE

To assess in a retrospective analysis of a prospectively collected database, the impact of increased age on 30-day postoperative outcomes of surgery for intracranial aneurysms (ICAs).

METHODS

721 adult patients who underwent surgery for ICA were identified in the 2006-2012 American College of Surgeons' National Surgical Quality Improvement Program. Baseline characteristics and 30-day outcomes were stratified by age: <50 years (n=221), 50-60 years (n=221), and >60 years (n=266). Patients <50 and 50-60 years old were propensity score-matched to those aged >60 years. Logistic regression was used to examine the relationship between increased age and surgical outcome.

RESULTS

In unadjusted analyses, age <50 years was associated with fewer postoperative complications (OR=0.5, 95% CI 0.3 to 0.7) and lower mortality (OR=0.4, 95% CI 0.2 to 0.9) compared with those aged >60 years. Patients aged between 50 and 60 years were less likely to have complications (OR=0.6, 95% CI 0.4 to 0.8) in unadjusted analyses. Upon propensity score matching, covariate balance was achieved for all age strata. In adjusted analyses, patients <50 years (OR=0.4, 95% CI 0.2 to 0.7) and 50-60 years (OR=0.5, 95% CI 0.3 to 0.8) of age continued to have fewer complications than those aged >60.

CONCLUSIONS

Age >60 is independently associated with 30-day postoperative morbidity in patients undergoing surgery for ICA. The results of this study suggest age >60 should be considered an a priori risk factor in surgical management of ICA, regardless of associated comorbidities often associated with increased age.

Meningoencephalocele of the temporal bone: pictorial essay on transmastoid extradural-intracranial repair

PURPOSE

A spontaneous meningoencephalocele of the temporal bone may present with effusion in the middle ear, a cerebrospinal fluid leak, hearing loss, or rarely otitic meningitis. Repair of spontaneous encephaloceles in the temporal bone has been performed using transmastoid and transcranial middle fossa approaches or a combination of the two with varied results. The authors present a technical paper on the transmastoid extradural intracranial approach for the management of temporal lobe encephaloceles.

MATERIALS/METHODS

Case reports and cadaver dissections are used to provide a pictorial essay on the technique. Advantages and disadvantages compared with alternative surgical approaches are discussed.

RESULTS

Traditional transmastoid approaches are less morbid compared with a transcranial repair as they avoid brain retraction. However, in the past, there has been a higher risk of graft failure and hearing loss due to downward graft migration and a potential need for ossicular disarticulation. For the appropriate lesion, the transmastoid extradural intracranial approach lesion offers a stable meningoencephalocele repair without the comorbidity of brain retraction.

CONCLUSION

The authors describe a transmastoid extradural intracranial technique via case reports and cadaver dissections for the repair of spontaneous meningoencephalocele defects larger than 2 cm. This approach provides more support to the graft compared to the conventional transmastoid repair.

Recurrences of ACTH-secreting adenomas after pituitary adenomectomy can be accurately predicted by perioperative measurements of plasma ACTH levels

BACKGROUND

Adenomectomy is the treatment of choice for ACTH-secreting adenomas. Although the development of ACTH deficiency immediately after adenomectomy suggests surgical success, disease recurrence was reported in patients who developed hypocortisolism postoperatively. In the current study, we examined the value of measuring perioperative plasma ACTH and cortisol levels in predicting disease recurrence of patients with ACTH-secreting adenomas.

METHODS

Consecutive patients (n = 55; 41 females, 14 males) with clinical, biochemical, and histological documentation of ACTH-secreting adenomas were investigated after pituitary adenomectomy. All patients were followed with clinical monitoring and frequent measurements of plasma ACTH and serum cortisol levels, and none received glucocorticoids unless or until they developed symptoms of adrenal insufficiency or when their serum cortisol levels were ≤3 μg/dL.

RESULTS

Postoperative serum cortisol levels reached ≤3 μg/dL in 46 of 55 and were ≥4 μg/dL in the remaining 9. Simultaneously measured plasma ACTH levels in the latter 9 patients were >40 ng/L when the serum cortisol reached its nadir. In contrast, among the 46 patients who had serum cortisol levels of ≤3 μg/dL, plasma ACTH levels measured simultaneously were ≤20 ng/L in 38 of 46 and >20 ng/L in the remaining 8. During a mean follow-up period of nearly 7 years, patients who had a nadir plasma ACTH of >20 ng/L developed recurrences even though their postoperative serum cortisol levels were ≤3 μg/dL.

CONCLUSIONS

Despite profound hypocortisolemia after adenomectomy, a simultaneously measured plasma ACTH level of >20 ng/L in the perioperative period is highly predictive of future recurrence of ACTH-secreting adenomas.

Abstract WP86: Anterior Communicating Artery Cerebral Aneurysms, 10-year Treatment Experience at a Tertiary Referral Medical Center: Large Prevalence of Ruptured Small Aneurysms

Purpose To determine patient characteristics and size distribution among ruptured and unruptured anterior communicating artery (AComA) aneurysms less than 7 mm treated with coiling or clipping in a 10-year time period at a tertiary referral medical center. A secondary objective is comparison of institutional data to published ISUIA data of 0% 5-year cumulative rupture risk for anterior circulation aneurysms < 7 mm.

Materials & Methods We retrospectively reviewed AComA aneurysm characteristics in all patients who were treated with coiling or clipping from December 2002 until June 2012. Aneurysm location and maximum sac diameter were recorded utilizing catheter angiography or computed tomography angiography.

Results In our series, 180 AComA aneurysms were treated from 12/2002 to 6/2012. 123 (68.0%) AComA aneurysms were treated in the setting of nontraumatic subarachnoid hemorrhage (SAH) while 57 (32.0%) were treated electively. Table 1 shows the characteristics of the AComA aneurysms in our series. Table 2 shows the size breakdown of ruptured and unruptured AComA aneurysms.

Table 1. AComA Aneurysm Characteristics.

Table 2. AComA Aneurysm Size Breakdown

Conclusion Among ruptured AComA aneurysms, 61.0% had a maximum diameter < 7 mm, while 35.0% were < 5 mm, which argues against the reported low risk of rupture in aneurysms < 7 mm based on the ISUIA trial. Further studies are recommended to correlate risk of rupture with such factors as personal or family history of subarachnoid hemorrhage, medical comorbidities, and documented growth of aneurysm.

Cerebral amyloid angiopathy-associated intracerebral hemorrhage: pathology and management

Amyloid angiopathy-associated intracerebral hemorrhage (ICH) comprises 12%-15% of lobar ICH in the elderly. This growing population has an increasing incidence of thrombolysis-related hemorrhages, causing the management of hemorrhages associated with cerebral amyloid angiopathy (CAA) to take center stage. A concise reference assimilating the pathology and management of this clinical entity does not exist. Amyloid angiopathy-associated hemorrhages are most often solitary, but the natural history often progresses to include multifocal and recurrent hemorrhages. Compared with other causes of ICH, patients with CAA-associated hemorrhages have a lower mortality rate but an increased risk of recurrence. Unlike hypertensive arteriolar hemorrhages that occur in penetrating subcortical vessels, CAA-associated hemorrhages are superficial in location due to preferential involvement of vessels in the cerebral cortex and meninges. This feature makes CAA-associated hemorrhages easier to access surgically. In this paper, the authors discuss 3 postulates regarding the pathogenesis of amyloid hemorrhages, as well as the established clinicopathological classification of amyloid angiopathy and CAA-associated ICH. Common inheritance patterns of familial CAA with hemorrhagic strokes are discussed along with the role of genetic screening in relatives of patients with CAA. The radiological characteristics of CAA are described with specific attention to CAA-associated microhemorrhages. The detection of these microhemorrhages may have important clinical implications on the administration of anticoagulation and antiplatelet therapy in patients with probable CAA. Poor patient outcome in CAA-associated ICH is associated with dementia, increasing age, hematoma volume and location, initial Glasgow Coma Scale score, and intraventricular extension. The surgical management strategies for amyloid hemorrhages are discussed with a review of published surgical case series and their outcomes with a special attention to postoperative hemorrhage.

Improvement of neurological recovery and stimulation of neural progenitor cell proliferation by intrathecal administration of Sonic hedgehog

OBJECT

Sonic hedgehog (Shh) is a glycoprotein molecule that has been shown to be associated with the proliferative capacity of endogenous neural precursor cells during embryonic development. It has also been shown to regulate the proliferative capacity of neural stem cells in the adult subventricular zone (SVZ), which are also upregulated in animal models of ischemic stroke. In the present study, the effects of exogenous administration of intrathecal Shh protein were examined in the setting of a rodent model of ischemic stroke, with particular attention given to endogenous neural stem cell proliferation and migration as well as inducible differences in behavioral recovery.

METHODS

A rodent model of ischemic stroke was created using the intraluminal suture method of reversible middle cerebral artery occlusion. Animals were treated with intrathecal administration of Shh protein at 24 hours after the onset of the stroke. Behavioral testing was performed, and the animals were killed for measurements of infarct volume 7 days after stroke. Immunohistochemical staining was performed and measurements of cellular proliferation were obtained, with a focus on the proportion and distribution of neural progenitor cells in the SVZ. These values were compared across experimental groups.

RESULTS

Treatment with intrathecal Shh protein resulted in significant improvement in behavioral function compared with the control group, with a significant reduction of ischemic tissue in the cerebral hemisphere. An increase of nestin immunoreactive cells was observed along the SVZ.

CONCLUSIONS

Intrathecal Shh agonist at doses that upregulate spinal cord GLI1 transcription increases the population of neural precursor cells after spinal cord injury in adult rats. Intrathecal administration of Shh protein appears to have a neuroprotective effect in animal models of ischemic stroke and is associated with improved behavioral recovery, which may be related to its effects on neurogenesis in the SVZ and could be associated with improved functional recovery.

Development of the Neurological Institute: a strategic, improvement, and systems approach

The Neurological Institute at University Hospitals Case Medical Center is designed to be responsive to the ever-changing healthcare environment, aligning clinical services and goals in response to internal and external pressures for change. These goals are many, including the further development of system integration across disciplines and geographic locations, creation of a regional strategy, and research as well as education strategies that are aligned with clinical services, patient outcomes that demonstrate improved health status management, and improved financial strength. There are many details to the development of a strategic business unit such as the Neurological Institute, but this article focuses on the high-level strategies of developing the Neurological Institute and takes a closer look at the growth of one of its 16 centers of excellence.

A novel method of translabyrinthine cranioplasty using hydroxyapatite cement and titanium mesh: a technical report

We report a novel technique for closure using titanium mesh cranioplasty in addition to hydroxyapatite cement and abdominal fat graft for acoustic neuroma. We reviewed 15 patients who underwent translabyrinthine craniectomy for resection of acoustic neuroma. Hearing loss was documented prior to surgical procedure. Over 2 years, patients underwent titanium mesh and hydroxyapatite cranioplasty with abdominal fat graft. Participants included seven men and eight women, age range 38 to 65. Main outcome measures included cosmetic outcome and incidence of cerebrospinal fluid (CSF) leak. The lesion was right-sided in seven patients and left-sided in eight. Cosmetic outcome was excellent in all. There were no cases of CSF leak. Closure used one-third the hydroxyapatite required for traditional closure. Our technique yields cosmetic results equivalent to hydroxyapatite cement alone and a comparable incidence of CSF leakage without leaving a drain in place postoperatively. The technique is easy to adopt, is more cost-effective than hydroxyapatite cement cranioplasty alone, offers greater ease of access for reoperation, and does not preclude later implantation of bone-anchored hearing aid.

Evidence-based review of primary and secondary ischemic stroke prevention in adults: a neurosurgical perspective

In this paper, the authors' aim is to provide an evidence-based review of primary and secondary ischemic stroke prevention guidelines covering most of the common risk factors and stroke etiologies for the practicing neurosurgeon. The key to stroke prevention is in the identification and treatment of the major risk factors for stroke. These include hypertension, heart disease, diabetes mellitus, dyslipidemia, and tobacco smoking. An updated approach to secondary prevention of stroke in the setting of intracranial and extracranial large vessel atherosclerosis and cardioembolism is provided along with a brief overview of pertinent clinical trials. Novel pharmacological options for prevention of cardioembolic strokes, such as new alternatives to warfarin, are addressed with recommendations for interruption of therapy for elective surgical procedures. In addition, the authors have reviewed the anticoagulation guidelines and the risk of thromboembolic complications of such therapies in the perioperative period, which is an invaluable piece of information for neurosurgeons. Less common etiologies such as arterial dissections and patent foramen ovale are also briefly discussed. Finally, the authors have outlined the quality measures in the Medicare Physician Quality Reporting System and essential guidelines for Primary Stroke Center certification, which have implications for day-to-day neurosurgical practice.

Rathke cleft cyst apoplexy: a newly characterized distinct clinical entity

Object

Although most Rathke cleft cysts (RCCs) remain asymptomatic, some present with compression of surrounding structures and pituitary hormone dysfunction. A rare, but distinct presentation of the RCC includes hemorrhage into the cyst—a presentation that mimics the clinical syndrome of pituitary tumor apoplexy. The objective of this article is to present the authors' experience on the prevalence and the clinical, biochemical, pathological, and imaging characteristics of hemorrhage into an RCC and review published reports on this entity.

Methods

An institutional database for patients with pituitary masses was reviewed and data on cases involving surgery for a subsequently documented RCC were identified. Patients with documented hemorrhage within the RCC were included in the analysis. Documentation included intraoperative visualization of hemorrhage by the surgeon and/or pathological confirmation of hemorrhage within the RCC. The clinical, biochemical, pathological, and imaging characteristics of these patients were extracted from the database. All published data on RCC were also reviewed and confirmed cases of hemorrhage were extracted and included in the review.

Results

A total of 11 cases with hemorrhage within an RCC were identified to have been managed at the authors' institution over a 10-year span. This figure represented 20% of all surgically treated cases of RCC from that period. Among published reports, a total of 10 confirmed cases were evaluated. The clinical presentation of patients with hemorrhage within an RCC are classical and include sudden onset of severe headache—or a sudden increase in headache severity—associated with visual disturbances, impairment in pituitary function, and occasionally alterations in mental status. Leakage of the cystic contents into the subarachnoid space can occur rarely and may lead to associated chemical meningitis. There are no known precipitating factors for this phenomenon. The clinical presentation of such patients is difficult to distinguish from that of patients with pituitary tumor apoplexy. However, patients with RCC apoplexy often present with less severe symptoms, have a lower prevalence of pituitary dysfunction, and generally have smaller mass lesions than those with pituitary tumor apoplexy. Management of patients with RCC apoplexy is similar to that of those with pituitary tumor apoplexy. Surgery can provide definitive diagnosis and relief of symptoms and often leads to recovery from hypopituitarism. All patients with this syndrome require long-term follow-up to treat any residual sequelae.

Conclusions

This article provides the first thorough review and characterization of patients with hemorrhage within an RCC. Based on the clinical manifestations of this presentation, we recommend using the term “Rathke cleft cyst apoplexy” to describe the syndrome.