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Technical modifications and decision-making to reduce morbidity in thoracic disc surgery: An institutional experience and treatment algorithm

Strom, Russell G; Mathur, Vin; Givans, Heather; Kondziolka, Douglas S; Perin, Noel I
BACKGROUND: Symptomatic thoracic disc herniation (TDH) is an uncommon condition with significant treatment risks. OBJECTIVE: To evaluate strategies to avoid and manage complications from thoracic disc surgery. METHODS: All TDH cases by the senior author were retrospectively reviewed from 2000 to 2012. Complications were recorded, together with avoidance and management strategies. To reduce access-related morbidity, a thoracoscopic-tubular retractor approach was developed later in the series. RESULTS: 64 patients were treated for TDH, the majority undergoing an anterior minimally-invasive approach. Complications occurred in 15 patients (23%). Three patients with intercostal neuralgia persisting for >3 months had pain resolution after intercostal nerve blocks and radiofrequency lesioning. Five of the six patients with dural tears during anterior surgery had no further events following dural repair, lumbar drain insertion, and placement of chest tube to water seal. One case of persistent CSF leakage was successfully treated with a laparoscopically-mobilized omental flap. Preoperative metallic marker placement was effective at guiding correct-level surgery. For anterior operations, no pneumothorax occurred with routine chest tube placement. Our approach and techniques evolved based on early experience, allowing us to reduce surgical morbidity. The thoracoscopic-tubular retractor approach was associated with low morbidity (no complications among 13 cases other than temporary intercostal neuralgia). CONCLUSIONS: Several strategies may reduce morbidity from thoracic disc surgery: careful approach selection, preoperative level marking, use a tubular retractor with thoracoscopic guidance, rib resection at the mini-thoracotomy site, routine chest tube placement for anterior operations, and routine lumbar drain insertion in the event of a dural tear. Prospective comparative studies are needed to assess the efficacy of these techniques.
PMID: 25867235
ISSN: 1872-6968
CID: 1532752

How Many Lesions Can Be Treated with Radiosurgery? Whole Brain Dose From Radiosurgery of Multiple Targets [Meeting Abstract]

Becker, S; Jozsef, G; Presser, I; Kondziolka, D
ISI:000356998303411
ISSN: 0094-2405
CID: 1718832

Development, Implementation, and Use of a Local and Global Clinical Registry for Neurosurgery

Kondziolka, Douglas; Cooper, Benjamin T; Lunsford, L Dade; Silverman, Joshua
Physicians are being challenged to obtain data for outcomes research and measures of quality practice in medicine. We developed a prospective data collection system (registry) that provides data points across all elements of a neurosurgical stereotactic radiosurgery practice. The registry architecture is scalable and suitable for any aspect of neurosurgical practice. Our purpose was to outline the challenges in creating systems for high quality data acquisition and describe experiences in initial testing and use. Over a two year period, a multicenter team working with software engineers developed a comprehensive radiosurgery registry based on a MS-Sequel(R) server platform. Three neurosurgeons at one center were responsible for final editing. Alpha testing began in September 2012 and server-based beta testing began in February 2013. The major elements included demographics, disease-based items (47 categories for different brain tumors, vascular malformations, and functional disorders) with relevant clinical grading systems, treatment-based items (imaging, physics, clinical), and follow-up data (clinical, imaging, subsequent therapeutics). Nine hundred patients were entered into the registry at one test center, with new entries and follow-up data entered daily at the point of contact. With experience, the mean time for one new entry was 6 minutes. Mean time for one follow-up entry was 45 seconds. The system was made secure for individual use and amenable for both data entry and research. Analytics used different filters to create customized outcomes charts as selected by the user (e.g., survival, neurologic function, complications). A local or multicenter prospective data collection registry was created for use across 47 clinical indications for stereotactic cranial radiosurgery. Further refinement of fields and logic is ongoing. The system is reliable, robust, and allows use of rapid analytical tools. Large medical registries will become widely used for collection and analysis of large data sets and should have broad applicability to many other elements of neurosurgical and medical practice.
PMID: 27447432
ISSN: 2167-647x
CID: 2191082

Brain arteriovenous malformations

Lawton, Michael T; Rutledge, W Caleb; Kim, Helen; Stapf, Christian; Whitehead, Kevin J; Li, Dean Y; Krings, Timo; terBrugge, Karel; Kondziolka, Douglas; Morgan, Michael K; Moon, Karam; Spetzler, Robert F
An arteriovenous malformation is a tangle of dysplastic vessels (nidus) fed by arteries and drained by veins without intervening capillaries, forming a high-flow, low-resistance shunt between the arterial and venous systems. Arteriovenous malformations in the brain have a low estimated prevalence but are an important cause of intracerebral haemorrhage in young adults. For previously unruptured malformations, bleeding rates are approximately 1% per year. Once ruptured, the subsequent risk increases fivefold, depending on associated aneurysms, deep locations, deep drainage and increasing age. Recent findings from novel animal models and genetic studies suggest that arteriovenous malformations, which were long considered congenital, arise from aberrant vasculogenesis, genetic mutations and/or angiogenesis after injury. The phenotypical characteristics of arteriovenous malformations differ among age groups, with fistulous lesions in children and nidal lesions in adults. Diagnosis mainly involves imaging techniques, including CT, MRI and angiography. Management includes observation, microsurgical resection, endovascular embolization and stereotactic radiosurgery, alone or in any combination. There is little consensus on how to manage patients with unruptured malformations; recent studies have shown that patients managed medically fared better than those with intervention at short-term follow-up. By contrast, interventional treatment is preferred following a ruptured malformation to prevent rehaemorrhage. Management continues to evolve as new mechanistic discoveries and reliable animal models raise the possibility of developing drugs that might prevent the formation of arteriovenous malformations, induce obliteration and/or stabilize vessels to reduce rupture risk. For an illustrated summary of this Primer, visit: http://go.nature.com/TMoAdn.
PMID: 27188382
ISSN: 2056-676x
CID: 4837072

Eye Tracking Detects Disconjugate Eye Movements Associated with Structural Traumatic Brain Injury and Concussion

Samadani, Uzma; Ritlop, Robert; Reyes, Marleen; Nehrbass, Elena; Li, Meng; Lamm, Elizabeth; Schneider, Julia; Shimunov, David; Sava, Maria; Kolecki, Radek; Burris, Paige; Altomare, Lindsey; Mehmood, Talha; Smith, Roland Theodore; Huang, Jason; McStay, Chris; Todd, Samual Rob; Qian, Meng; Kondziolka, Douglas; Wall, Stephen; Huang, Paul
Introduction: Disconjugate eye movements have been associated with traumatic brain injury since ancient times. Ocular motility dysfunction may be present in up to 90% of patients with concussion or blast injury. Methods: We developed an algorithm for eye tracking in which the Cartesian coordinates of the right and left pupils are tracked over 200 seconds and compared to each other as a subject watches a short film clip moving inside an aperture on a computer screen. We prospectively eye tracked 64 normal healthy non-injured control subjects and compared findings to 75 trauma subjects with either a positive head CT (n=13), negative head CT (n=39) or non-head injury (n=23) to determine whether eye tracking would reveal the disconjugate gaze associated with both structural brain injury and concussion. Tracking metrics were then correlated to the clinical concussion measure SCAT3 in trauma patients. Results: Five out of five measures of horizontal disconjugacy were increased in positive and negative head CT patients relative to non-injured control subjects. Only one of five vertical disconjugacy measures was significantly increased in brain injured patients relative to controls. Linear regression analysis of all 75 trauma patients demonstrated that three metrics for horizontal disconjugacy negatively correlated with SCAT3 symptom severity score and positively correlated with total Standardized Assessment of Concussion (SAC) score. Abnormal eye tracking metrics improved over time towards baseline in brain injured subjects seen in follow-up. Conclusions: Eye tracking may help quantify the severity of ocular motility disruption associated with concussion and structural brain injury.
PMCID:4394159
PMID: 25582436
ISSN: 0897-7151
CID: 1436112

Stereotactic radiosurgery for intracranial meningiomas: current concepts and future perspectives

Mansouri, Alireza; Guha, Daipayan; Klironomos, George; Larjani, Soroush; Zadeh, Gelareh; Kondziolka, Douglas
: Meningiomas are among the most common adult brain tumors. Although the optimal management of meningiomas would provide complete elimination of the lesion, this cannot always be accomplished safely through resection. Therefore, other therapeutic modalities, such as stereotactic radiosurgery (as primary or adjunctive therapy), have emerged. In the current review, we have provided an overview of the historical outcomes of various radiosurgical modalities applied in the management of meningiomas. Furthermore, we provide a discussion on key factors (eg World Health Organization grade, lesion size, and lesion location) that affect tumor control and adverse event rates. We discuss recent changes in our understanding of meningiomas, based on molecular and genetic markers, and how these will change our perspective on the management of meningiomas. We conclude by outlining the areas in which knowledge gaps persist and provide suggestions as to how these can be addressed. ABBREVIATIONS: ARE, adverse radiation eventCI, conformity indexFSRT, fractionated radiotherapyGK, Gamma KnifeGTR, gross total resectionHGM, high-grade meningiomaLINAC, linear acceleratorNF2, neurofibromatosis type 2OA, optic apparatusOS, overall survivalPFS, progression-free survivalSRS, stereotactic radiosurgerySTR, subtotal resectionTC, tumor controlVS, vestibular schwannomaWHO, World Health Organization.
PMID: 25599213
ISSN: 0148-396x
CID: 1506782

Role of adjuvant or salvage radiosurgery in the management of unresected residual or progressive glioblastoma multiforme in the pre-bevacizumab era

Niranjan, Ajay; Kano, Hideyuki; Iyer, Aditya; Kondziolka, Douglas; Flickinger, John C; Lunsford, L Dade
OBJECT After initial standard of care management of glioblastoma multiforme (GBM), relatively few proven options remain for patients with unresected progressive tumor. Numerous reports describe the value of radiosurgery, yet this modality appears to remain underutilized. The authors analyzed the outcomes of early adjuvant stereotactic radiosurgery (SRS) for unresected tumor or later salvage SRS for progressive GBM. Radiosurgery was performed as part of the multimodality management and was combined with other therapies. Patients continued to receive additional chemotherapy after SRS and prior to progression being documented. In this retrospective analysis, the authors evaluated factors that affected patient overall survival (OS) and progression-free survival. METHODS Between 1987 and 2008 the authors performed Gamma Knife SRS in 297 patients with histologically proven GBMs. All patients had received prior fractionated radiation therapy, and 66% had undergone one or more chemotherapy regimens. Ninety-six patients with deep-seated unresectable GBMs underwent biopsy only. Of those in whom excision had been possible, resection was considered to be gross total in 68 and subtotal in 133. The median patient age was 58 years (range 23-89 years) and the median tumor volume was 14 cm(3) (range 0.26-84.2 cm(3)). The median prescription dose delivered to the imaging-defined tumor margin was 15 Gy (range 9-25 Gy). The median follow-up duration was 8.6 months (range 1.1-173 months). Cox regression models were used to analyze survival outcomes. Variables examined included age, residual versus recurrent tumor, prior chemotherapy, time to first recurrence, SRS dose, and gross tumor volume. RESULTS The median survival times after radiosurgery and after diagnosis were 9.03 and 18.1 months, respectively. The 1-year and 2-year OS after SRS were 37.9% and 16.7%, respectively. The 1-year and 2-year OS after diagnosis were 76.2% and 30.8%, respectively. Using multivariate analysis, factors associated with improved OS after diagnosis were younger age (< 60 years) at diagnosis (p < 0.0001), tumor volume < 14 cm(3) (p < 0.001), use of prior chemotherapy (p = 0.001), and radiosurgery at the time of recurrence (p < 0.0001). Multivariate analysis showed that younger age (p < 0.0001) and smaller tumor volume (< 14 cm(3)) (p = 0.001) were significantly associated with increased OS after SRS. Adverse radiation effects were seen in 69 patients (23%). Fifty-eight patients (19.5%) underwent additional resection after SRS. The median survivals after diagnosis for recursive partitioning analysis Classes III, IV and V+VI were 31.6, 20.8, and 16.7 months, respectively. CONCLUSIONS In this analysis 30% of a heterogeneous cohort of GBM patients eligible for SRS had an OS of 2 years. Radiosurgery at the time of tumor progression was associated with a median survival of 21.8 months. The role of radiosurgery for GBMs remains controversial. The findings in this study support the need for a funded and appropriately designed clinical trial that will provide a higher level of evidence regarding the future role of SRS for glioblastoma patients in whom disease has progressed despite standard management.
PMID: 25594327
ISSN: 1933-0693
CID: 1539502

Neurosurgical decision making: personal and professional preferences

Tanweer, Omar; Wilson, Taylor A; Kalhorn, Stephen P; Golfinos, John G; Huang, Paul P; Kondziolka, Douglas
OBJECT Physicians are often solicited by patients or colleagues for clinical recommendations they would make for themselves if faced by a clinical situation. The act of making a recommendation can alter the clinical course being taken. The authors sought to understand this dynamic across different neurosurgical scenarios by examining how neurosurgeons value the procedures that they offer. METHODS The authors conducted an online survey using the Congress of Neurological Surgeons listserv in May 2013. Respondents were randomized to answer either as the surgeon or as the patient. Questions encompassed an array of distinct neurosurgical scenarios. Data on practice parameters and experience levels were also collected. RESULTS Of the 534 survey responses, 279 responded as the "neurosurgeon" and 255 as the "patient." For both vestibular schwannoma and arteriovenous malformation management, more respondents chose resection for their patient but radiosurgery for themselves (p = 0.002 and p = 0.001, respectively). Aneurysm coiling was chosen more often than clipping, but those whose practice was >/= 30% open cerebrovascular neurosurgery were less likely to choose coiling. Overall, neurosurgeons who focus predominantly on tumors were more aggressive in managing the glioma, vestibular schwannoma, arteriovenous malformation, and trauma. Neurosurgeons more than 10 years out of residency were less likely to recommend surgery for management of spinal pain, aneurysm, arteriovenous malformation, and trauma scenarios. CONCLUSIONS In the majority of cases, altering the role of the surgeon did not change the decision to pursue treatment. In certain clinical scenarios, however, neurosurgeons chose treatment options for themselves that were different from what they would have chosen for (or recommended to) their patients. For the management of vestibular schwannomas, arteriovenous malformations, intracranial aneurysms, and hypertensive hemorrhages, responses favored less invasive interventions when the surgeon was the patient. These findings are likely a result of cognitive biases, previous training, experience, areas of expertise, and personal values.
PMID: 25574570
ISSN: 0022-3085
CID: 1432972

Detection of third and sixth cranial nerve palsies with a novel method for eye tracking while watching a short film clip

Samadani, Uzma; Farooq, Sameer; Ritlop, Robert; Warren, Floyd; Reyes, Marleen; Lamm, Elizabeth; Alex, Anastasia; Nehrbass, Elena; Kolecki, Radek; Jureller, Michael; Schneider, Julia; Chen, Agnes; Shi, Chen; Mendhiratta, Neil; Huang, Jason H; Qian, Meng; Kwak, Roy; Mikheev, Artem; Rusinek, Henry; George, Ajax; Fergus, Robert; Kondziolka, Douglas; Huang, Paul P; Smith, R Theodore
OBJECT Automated eye movement tracking may provide clues to nervous system function at many levels. Spatial calibration of the eye tracking device requires the subject to have relatively intact ocular motility that implies function of cranial nerves (CNs) III (oculomotor), IV (trochlear), and VI (abducent) and their associated nuclei, along with the multiple regions of the brain imparting cognition and volition. The authors have developed a technique for eye tracking that uses temporal rather than spatial calibration, enabling detection of impaired ability to move the pupil relative to normal (neurologically healthy) control volunteers. This work was performed to demonstrate that this technique may detect CN palsies related to brain compression and to provide insight into how the technique may be of value for evaluating neuropathological conditions associated with CN palsy, such as hydrocephalus or acute mass effect. METHODS The authors recorded subjects' eye movements by using an Eyelink 1000 eye tracker sampling at 500 Hz over 200 seconds while the subject viewed a music video playing inside an aperture on a computer monitor. The aperture moved in a rectangular pattern over a fixed time period. This technique was used to assess ocular motility in 157 neurologically healthy control subjects and 12 patients with either clinical CN III or VI palsy confirmed by neuro-ophthalmological examination, or surgically treatable pathological conditions potentially impacting these nerves. The authors compared the ratio of vertical to horizontal eye movement (height/width defined as aspect ratio) in normal and test subjects. RESULTS In 157 normal controls, the aspect ratio (height/width) for the left eye had a mean value +/- SD of 1.0117 +/- 0.0706. For the right eye, the aspect ratio had a mean of 1.0077 +/- 0.0679 in these 157 subjects. There was no difference between sexes or ages. A patient with known CN VI palsy had a significantly increased aspect ratio (1.39), whereas 2 patients with known CN III palsy had significantly decreased ratios of 0.19 and 0.06, respectively. Three patients with surgically treatable pathological conditions impacting CN VI, such as infratentorial mass effect or hydrocephalus, had significantly increased ratios (1.84, 1.44, and 1.34, respectively) relative to normal controls, and 6 patients with supratentorial mass effect had significantly decreased ratios (0.27, 0.53, 0.62, 0.45, 0.49, and 0.41, respectively). These alterations in eye tracking all reverted to normal ranges after surgical treatment of underlying pathological conditions in these 9 neurosurgical cases. CONCLUSIONS This proof of concept series of cases suggests that the use of eye tracking to detect CN palsy while the patient watches television or its equivalent represents a new capacity for this technology. It may provide a new tool for the assessment of multiple CNS functions that can potentially be useful in the assessment of awake patients with elevated intracranial pressure from hydrocephalus or trauma.
PMCID:4547625
PMID: 25495739
ISSN: 0022-3085
CID: 1410622

White matter changes in breast cancer brain metastases patients who undergo radiosurgery alone compared to whole brain radiation therapy plus radiosurgery

Stokes, Timothy B; Niranjan, Ajay; Kano, Hideyuki; Choi, Phillip A; Kondziolka, Douglas; Dade Lunsford, L; Monaco, Edward A 3rd
Delayed toxicity after whole brain radiation therapy (WBRT) is of increasing concern in patients who survive more than one year with brain metastases from breast cancer. Radiation-related white matter toxicity is detected by magnetic resonance imaging (MRI) and has been correlated with neurocognitive dysfunction. This study assessed the risk of developing white matter changes (WMC) in breast cancer patients who underwent either WBRT plus stereotactic radiosurgery (SRS) or SRS alone. We retrospectively compared 35 patients with breast cancer brain metastases who received WBRT and SRS to 30 patients who only received SRS. All patients had evaluable imaging at a median of one year after their initial management. The development of white matter T2 prolongation as detected by T2 or FLAIR imaging was graded: grade 1 = little or no white matter T2 hyperintensity; grade 2 = limited periventricular hyperintensity; and grade 3 = diffuse white matter hyperintensity. After WBRT plus SRS, patients demonstrated a significantly higher incidence of WMC (p < 0.0001). After one year, 71.5 % of patients whose treatment included WBRT demonstrated WMC (42.9 % grade 2; 28.6 % grade 3). Only one patient receiving only SRS developed WMC. In long-term survivors of breast cancer, the risk of WMC was significantly reduced when SRS alone was used for management. Further prospective studies are necessary to determine how these findings correlate with neurocognitive toxicity. WBRT usage as initial management of limited brain disease should be replaced by SRS alone to reduce the risk of delayed white matter toxicity.
PMID: 25445836
ISSN: 0167-594x
CID: 1486892