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Kunakorn Atchaneeyasakul, Anita Tipirneni, Tony Zhang, Priyank Khandelwal, Sudheer Ambekar, Brian Snelling, Sushrut Dharmadhikari, Chuanhui Dong, Luis Guada, Kevin Ramdas, Seemant Chaturvedi, Tatjana Rundek and Dileep R. Yavagal

OBJECTIVE

Thyroid disorder has been known to affect vascular function and has been associated with aortic aneurysm formation in some cases; however, the connection has not been well studied. The authors hypothesized that hypothyroidism is associated with the formation of cerebral aneurysms.

METHODS

The authors performed a retrospective case-control study of consecutive patients who had undergone cerebral angiography at an academic, tertiary care medical center in the period from April 2004 through April 2014. Patients with unruptured aneurysms were identified from among those who had undergone 3-vessel catheter angiography. Age-matched controls without cerebral aneurysms on angiography were also identified from the same database. Patients with previous subarachnoid hemorrhage or intracranial hemorrhage were excluded. History of hypothyroidism and other risk factors were recorded.

RESULTS

Two hundred forty-three patients with unruptured cerebral aneurysms were identified and age matched with 243 controls. Mean aneurysm size was 9.6 ± 0.8 mm. Hypothyroidism was present in 40 patients (16.5%) and 9 matched controls (3.7%; adjusted OR 3.2, 95% CI 1.3–7.8, p = 0.01). Subgroup analysis showed that men with hypothyroidism had higher odds of an unruptured cerebral aneurysm diagnosis than the women with hypothyroidism, with an adjusted OR of 12.7 (95% CI 1.3–121.9) versus an OR of 2.5 (95% CI 1.0–6.4) on multivariate analysis.

CONCLUSIONS

Hypothyroidism appears to be independently associated with unruptured cerebral aneurysms, with a higher effect seen in men. Given the known pathophysiological associations between hypothyroidism and vascular dysfunction, this finding warrants further exploration.

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Joaquin E. Jimenez, Zachary C. Gersey, Jason Wagner, Brian Snelling, Sudheer Ambekar and Eric C. Peterson

OBJECTIVE

Pediatric patients are at risk for the recurrence of brain arteriovenous malformation (AVM) after resection. While there is general consensus on the importance of follow-up after surgical removal of an AVM, there is a lack of consistency in the duration of that follow-up. The object of this systematic review was to examine the role of follow-up imaging in detecting AVM recurrence early and preventing AVM rupture.

METHODS

This systematic review was performed using articles obtained through a search of the literature contained in the MeSH database, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Search results revealed 1052 articles, 13 of which described 31 cases of AVM recurrence meeting the criteria for inclusion in this study. Detection of AVM occurred significantly earlier (mean ± SD, 3.56 ± 3.67 years) in patients with follow-up imaging than in those without (mean 8.86 ± 5.61 years; p = 0.0169). While 13.34% of patients who underwent follow-up imaging presented with rupture of a recurrent AVM, 57.14% of those without follow-up imaging presented with a ruptured recurrence (p = 0.0377).

CONCLUSIONS

Follow-up imaging has an integral role after AVM resection and is sometimes not performed for a sufficient period, leading to delayed detection of recurrence and an increased likelihood of a ruptured recurrent AVM.

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Sudheer Ambekar, Brandon G. Gaynor, Eric C. Peterson and Mohamed Samy Elhammady

OBJECT

Dural arteriovenous fistulas (DAVFs) are complex lesions consisting of abnormal connections between meningeal arteries and dural venous sinuses and/or cerebral veins. The goal of treatment is surgical or endovascular occlusion of the fistula or fistulous nidus or at least the disconnection of the feeding vessels and the draining veins. Delayed angiographic data on previously embolized dural fistulas is lacking. The authors report their experience and the long-term angiographic results with embolization of intracranial DAVF using Onyx.

METHODS

All cases of DAVF treated primarily with Onyx at the authors’ institution from 2006 to 2013 were retrospectively reviewed. Patient demographics, fistula characteristics, embolization details, and angiographic follow-up were analyzed.

RESULTS

Fifty-eight patients with DAVFs were treated during the study period. Twenty-two patients were treated with open surgery with or without prior embolization. Thirty-six patients were treated with embolization alone, of whom 26 underwent an attempt at curative embolization and are the subject of this review. All but 2 of these patients were treated in a single session. Angiographic “cure” was achieved in all cases following treatment. Follow-up angiography was performed in 21 patients at a mean of 14 months after treatment (range 2–39 months). Asymptomatic angiographic recurrence of the fistula was evident in 3 of the 21 patients (14.3%). On reviewing the procedural angiograms of the cases in which the DAVFs recurred, it was observed that the Onyx cast did not reach the venous portion in 1 case, whereas it did reach the vein in the other 2 cases.

CONCLUSIONS

Recurrence following initial angiographic cure of DAVF is not uncommon. Incomplete penetration of the embolic material into the proximal portion of the venous outlet may lead to delayed recurrence. Long-term angiographic follow-up is highly recommended.

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Shyamal C. Bir, Sudheer Ambekar, Sunil Kukreja and Anil Nanda

Julius Caesar Arantius is one of the pioneer anatomists and surgeons of the 16th century who discovered the different anatomical structures of the human body. One of his prominent discoveries is the hippocampus. At that time, Arantius originated the term hippocampus, from the Greek word for seahorse (hippos [“horse”] and kampos [“sea monster”]). Arantius published his description of the hippocampus in 1587, in the first chapter of his work titled De Humano Foetu Liber. Numerous nomenclatures of this structure, including “white silkworm,” “Ammon's horn,” and “ram's horn” were proposed by different scholars at that time. However, the term hippocampus has become the most widely used in the literature.

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Sunil Kukreja, Sudheer Ambekar, Mayur Sharma and Anil Nanda

The authors report the case of a spinal intradural schwannoma presenting with intracranial subarachnoid hemorrhage (SAH). Cerebral angiography did not show any intracranial lesion; however, MRI revealed two separate tumors in the lower segment of the spinal cord. The proximal lesion arising from the conus medullaris was well circumscribed and homogeneously enhanced, whereas the tumor in the cauda equina revealed hemorrhagic signals on MRI. This case also illustrates an unusual presentation of intracranial SAH simultaneously with intratumoral hemorrhage in a spinal cord schwannoma. The absence of hemorrhagic changes in the lesion arising proximal to the cauda equina region supports the mechanical theory proposed for the pathogenesis of hemorrhagic complications in spinal cord tumors.

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Sunil Kukreja, Sudheer Ambekar, Anthony Hunkyun Sin and Anil Nanda

Object

Reports of myxopapillary ependymomas (MPEs) of the spinal cord in pediatric patients are scarce. In the literature, various authors have shared their experiences with small groups of patients, which makes it difficult to create a consensus regarding the treatment approach for spinal MPEs in young patients. The aim of this study was to perform a survival analysis of patients in the first 2 decades of life whose cases were selected from the published studies, and to examine the influence of various factors on outcomes.

Methods

A comprehensive search of studies published in English was performed on PubMed. Patients whose age was ≤ 20 years were included for integrative analysis. Information about age, treatment characteristics, critical events (progression, recurrence, and death), time to critical events, and follow-up duration was recorded. The degree of association of the various factors with the survival outcome was calculated by using Kaplan-Meier estimator and Cox proportional hazard model techniques.

Results

A total of 95 patients were included in the analysis. The overall rate of recurrence (RR) was 34.7% (n = 33), with a median time to recurrence of 36 months (range 2–100 months). Progression-free survival (PFS) and overall survival rates at 5 years were 73.7% and 98.9%, respectively. Addition of radiotherapy (RT) following resection significantly improved PFS (log-rank test, p = 0.008). In patients who underwent subtotal resection (STR), administering RT (STR + RT) improved outcome with the lowest failure rates (10.3%), superior to patients who underwent gross-total resection (GTR) alone (RR 43.1%; log-rank test, p < 0.001). Addition of RT to patients who underwent GTR was not beneficial (log-rank test, p = 0.628). In patients who had disseminated tumor at presentation, adjuvant RT controlled the disease effectively. High-dose RT (≥ 50 Gy) did not change PFS (log-rank test, p = 0.710).

Conclusions

Routine inclusion of RT in the treatment protocol for spinal MPEs in young patients should be considered. Complete resection is always the goal of tumor resection. However, when complete resection does not seem to be possible in complex lesions, RT should be used as an adjunct to avoid aggressive resection and to minimize inadvertent injury to the surrounding neural tissues. High-dose RT (≥ 50 Gy) did not provide additional survival benefits, although this association needs to be evaluated by prospective studies.

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Shyamal C. Bir, Sudheer Ambekar, Christina Notarianni and Anil Nanda

In the 19th century, Dr. Odilon Marc Lannelongue was a pioneering French surgeon who introduced a surgical technique for the treatment of craniosynostosis. In 1890, Dr. Lannelongue performed correction of sagittal synostosis by strip craniectomy. From his procedure, multiple techniques have been developed and endorsed for this condition, ranging from simple suturectomies to extensive calvarial vault remodeling. In addition, even today, endoscopically aided strip craniectomy is performed as a surgical treatment of craniosynostosis. This article describes the life and works of the surgeon who revolutionized the management of craniosynostosis.

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Mayur Sharma, Ashish Sonig, Sudheer Ambekar and Anil Nanda

Object

The aim of this study was to analyze the incidence of adverse outcomes and inpatient mortality following resection of intramedullary spinal cord tumors by using the US Nationwide Inpatient Sample (NIS) database. The overall complication rate, length of the hospital stay, and the total cost of hospitalization were also analyzed from the database.

Methods

This is a retrospective cohort study conducted using the NIS data from 2003 to 2010. Various patient-related (demographic categories, complications, comorbidities, and median household income) and hospital-related variables (number of beds, high/low case volume, rural/urban location, region, ownership, and teaching status) were analyzed from the database. The adverse discharge disposition, in-hospital mortality, and the higher cost of hospitalization were taken as the dependent variables.

Results

A total of 15,545 admissions were identified from the NIS database. The mean patient age was 44.84 ± 19.49 years (mean ± SD), and 7938 (52%) of the patients were male. Regarding discharge disposition, 64.1% (n = 9917) of the patients were discharged to home or self-care, and the overall in-hospital mortality rate was 0.46% (n = 71). The mean total charges for hospitalization increased from $45,452.24 in 2003 to $76,698.96 in 2010. Elderly patients, female sex, black race, and lower income based on ZIP code were the independent predictors of other than routine (OTR) disposition (p < 0.001). Private insurance showed a protective effect against OTR disposition. Patients with a higher comorbidity index (OR 1.908, 95% CI 1.733–2.101; p < 0.001) and with complications (OR 2.214, 95% CI 1.768–2.772; p < 0.001) were more likely to have an adverse discharge disposition. Hospitals with a larger number of beds and those in the Northeast region were independent predictors of the OTR discharge disposition (p < 0.001). Admissions on weekends and nonelective admission had significant influence on the disposition (p < 0.001). Weekend and nonelective admissions were found to be independent predictors of inpatient mortality and the higher cost incurred to the hospitals (p < 0.001). High-volume and large hospitals, West region, and teaching hospitals were also the predictors of higher cost incurred to the hospitals (p < 0.001). The following variables (young patients, higher median household income, nonprivate insurance, presence of complications, and a higher comorbidity index) were significantly correlated with higher hospital charges (p < 0.001), whereas the variables young patients, nonprivate insurance, higher median household income, and higher comorbidity index independently predicted for inpatient mortality (p < 0.001).

Conclusions

The independent predictors of adverse discharge disposition were as follows: elderly patients, female sex, black race, lower median household income, nonprivate insurance, higher comorbidity index, presence of complications, larger hospital size, Northeast region, and weekend and nonelective admissions. The predictors of higher cost incurred to the hospitals were as follows: young patients, higher median household income, nonprivate insurance, presence of complications, higher comorbidity index, hospitals with high volume and a large number of beds, West region, teaching hospitals, and weekend and nonelective admissions.