Journal of Neurosurgery

Publisher: American Association of Neurological Surgeons, American Association of Neurological Surgeons

Journal description

Current impact factor: 3.74

Impact Factor Rankings

2015 Impact Factor Available summer 2016
2014 Impact Factor 3.737
2011 Impact Factor 2.965

Additional details

5-year impact 3.57
Cited half-life >10.0
Immediacy index 0.63
Eigenfactor 0.03
Article influence 1.13
Other titles Journal of neurosurgery (Online), Journal of neurosurgery, JNS
ISSN 1933-0693
OCLC 44743688
Material type Document, Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

American Association of Neurological Surgeons

  • Pre-print
    • Author cannot archive a pre-print version
  • Post-print
    • Author cannot archive a post-print version
  • Conditions
    • NIH authors may submit articles to PubMed Central 12 months after publication (publisher will supply necessary files)
    • Wellcome Trust authors may comply with their grant conditions
    • Publisher last reviewed on 24/06/2015
  • Classification
    ​ white

Publications in this journal

  • Journal of Neurosurgery 10/2015; DOI:10.3171/2015.7.JNS111360r
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    ABSTRACT: OBJECT Thrombosis of the cerebral arteries is one of the complications of microsurgical operations for partially thrombosed intracranial aneurysms. The object of this study was to assess the frequency of intraoperative arterial thrombosis (IAT) during microsurgical treatment of large and giant partially thrombosed aneurysms of the middle cerebral artery (MCA) and also to assess the efficacy of the treatment of this complication. MATERIALS The authors analyzed a consecutive series of 53 patients who underwent surgery for partially thrombosed aneurysms of the MCA at the Burdenko Neurosurgical Institute between January 2005 and September 2014. Thirty-two patients had large aneurysms (15-25 mm) and 21 had giant aneurysms (> 25 mm). Clipping of aneurysms was performed in 47 patients, trapping was performed in 3, and wrapping was performed in 3. RESULTS IAT was diagnosed in 10 patients (18.9%). The authors describe a technique for IAT reversal involving the injection of modified human recombinant prourokinase (mr-proUK). Of the 7 patients who underwent injection of mr-proUK in the thrombosed artery, 5 (71.4%) were discharged without any change in neurological status, 1 (14.3%) experienced moderate deterioration (modified Rankin Scale [mRS] score of 2), and 1 (14.3%) experienced severe deterioration (mRS score of 4). Among the 3 patients who had complications and did not receive an injection of mr-proUK, 2 experienced severe deterioration (mRS score of 3 and 4) and 1 had moderate deterioration (mRS score of 2). CONCLUSIONS The primary risk factor of thrombectomy with temporary trapping is thrombosis in the MCA branches. The injection of a fibrinolytic agent into thrombosed MCA branches is an effective method for the treatment of IAT.
    Journal of Neurosurgery 10/2015; DOI:10.3171/2015.2.JNS142655
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    ABSTRACT: OBJECT The authors of this study sought to assess tumor control and complication rates in a large cohort of patients who underwent Gamma Knife radiosurgery (GKRS) for vestibular schwannoma (VS) and to identify predictors of tumor control. METHODS The records of 420 patients treated with GKRS for VS with a median marginal dose of 11 Gy were retrospectively analyzed. Patients with neurofibromatosis Type 2 or who had undergone treatment for VS previously were excluded. The authors assessed tumor control and complication rates with chart review and used the Cox proportional hazards model to identify predictors of tumor control. Preservation of serviceable hearing, defined as Gardner-Robertson Class I-II, was evaluated in a subgroup of 71 patients with serviceable hearing at baseline and with available follow-up audiograms. RESULTS The median VS tumor volume was 1.4 cm(3), and the median length of follow-up was 5.1 years. Actuarial 5-and 10-year tumor control rates were 91.3% and 84.8%, respectively. Only tumor volume was a statistically significant predictor of tumor control rate. The tumor control rate decreased from 94.1% for tumors smaller than 0.5 cm(3) to 80.7% for tumors larger than 6 cm(3). Thirteen patients (3.1%) had new or increased permanent trigeminal nerve neuropathy, 4 (1.0%) had new or increased permanent facial weakness, and 5 (1.2%) exhibited new or increased hydrocephalus requiring a shunting procedure. Actuarial 3-year and 5-year hearing preservation rates were 65% and 42%, respectively. CONCLUSIONS The 5-year actuarial tumor control rate of 91.3% in this cohort of patients with VS compared slightly unfavorably with the rates reported in other large studies, but the complication and hearing preservation rates in this study were similar to those reported previously. Various factors may contribute to the observed differences in reported outcomes. These factors include variations in treatment indication and in the definition of treatment failure, as well as a lack of standardization of terminology and of evaluation of complications. Last, differences in dosimetric variables may also be an explanatory factor.
    Journal of Neurosurgery 10/2015; DOI:10.3171/2015.4.JNS142415
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    ABSTRACT: OBJECT Removal of jugular foramen (JF) tumors usually requires extensive skull base approaches and is frequently associated with postoperative morbidities such as lower cranial nerve injury. The endoscope-assisted retrosigmoid infralabyrinthine approach is a relatively new approach to tumors extending into the bony canal of the JF. The authors present their experience with this approach. METHODS The endoscope-assisted retrosigmoid infralabyrinthine approach was used in 7 patients, including 5 with schwannomas and 2 with paragangliomas. The access to the tumor, extent of its removal, postoperative neurological outcome, and approach-related morbidities were evaluated. RESULTS Two patients had a history of previous partial tumor removal, and 1 was treated by embolization followed by two courses of Gamma Knife radiosurgery. In this latter patient near-total resection was achieved. Gross-total resection was possible in the remaining 6 patients. Five patients benefited from endoscopic assistance: in 2 patients it showed a tumor remnant after microscopic tumor removal, while in 3 patients it allowed safe removal of the intraforaminal tumor by visualizing the surrounding structures. No permanent neurological deficit was observed after the operation. Two patients presenting with swallowing disturbance had temporary postoperative worsening that improved later. One patient developed CSF leakage that was managed with a lumbar drain. CONCLUSIONS This study shows that the judicious application of the endoscope-assisted retrosigmoid infralabyrinthine approach is safe and effective for removal of the schwannomas extending into the JF and selected paragangliomas without significant luminal invasion of the sigmoid-jugular system.
    Journal of Neurosurgery 10/2015; DOI:10.3171/2015.3.JNS142904
  • Journal of Neurosurgery 10/2015; DOI:10.3171/2015.7.JNS09850r
  • Journal of Neurosurgery 10/2015; DOI:10.3171/2015.7.JNS111580r
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    ABSTRACT: OBJECT By exploring longitudinal patient-reported health-related quality of life (HRQoL), the authors sought to assess the quality of survival for patients in the 1st year after diagnosis of glioblastoma. METHODS Thirty unselected patients ≥ 18 years who underwent primary surgery for glioblastoma in the period 2011-2013 were included. Using the generic HRQoL questionnaire EQ-5D 3L, baseline HRQoL was assessed before surgery and at postoperative follow-up after 1, 2, 4, 6, 8, 10, and 12 months. RESULTS There was an apparent correlation between deterioration in HRQoL scores and tumor progression. Patients with permanent deterioration in HRQoL early after surgery represented a subgroup with rapid progression and short survival. Both positive and negative changes in HRQoL were more often seen after surgery than after radio- or chemotherapy. Patients with gross-total resection (GTR) reported better and more stable HRQoL. In a multivariable analysis preoperative cognitive symptoms (p = 0.02), preoperative functional status (p = 0.03), and GTR (p = 0.01) were independent predictors of quality of survival (area under the curve for EQ-5D 3L index values). CONCLUSIONS The results indicate that progression-free survival is not only a surrogate marker for survival, but also for quality of survival. Quality of survival seems to be associated with GTR, which adds further support for opting for extensive resections in glioblastoma patients with good preoperative functional levels.
    Journal of Neurosurgery 10/2015; DOI:10.3171/2015.4.JNS15194
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    ABSTRACT: OBJECT Neurosurgical patients bear a varying degree of anxiety when confronted with having to undergo surgery or even visit with a neurosurgeon in consultation. Previous studies have suggested that patient perceptions can heavily influence the patient-physician encounter. Accordingly, a better understanding of these perceptions can marshal our knowledge regarding strategies for improving patient-physician interactions during such an apprehensive time. The aim of the present study was to qualitatively examine patient values and preferences for a neurosurgeon who participates in extraclinical activities (i.e., a "neurosurgeon+") and understand the factors that influence these perceptions. METHODS Semistructured face-to-face interviews with 47 neurosurgical patients were conducted. Patients were recruited from the Toronto Western Hospital neurosurgery clinics for cranial and spinal conditions. Descriptive summary statistics were used to characterize the study participants. Family members were encouraged to contribute to the interviews. Interviews were audio-recorded, transcribed, and subjected to thematic analysis by using open and axial coding. RESULTS Patients generally indicated that they want to feel confident in their neurosurgeon. A number of factors contribute to this confidence, including a strong positive referral from another physician. Patients are inclined to search for information pertaining to the qualifications of neurosurgeons online, and a perception of the neurosurgeon's adeptness given his or her qualifications is important for patients. Although there were some differences in patient values between those in the cranial and spinal groups, overall, neurosurgical patients tend to positively view their neurosurgeon's involvement in extraclinical duties. CONCLUSIONS This study details the first comprehensive clinical qualitative study of patient perceptions of neurosurgeons and provides a descriptive framework for understanding patient values in this clinical domain.
    Journal of Neurosurgery 10/2015; DOI:10.3171/2015.4.JNS15113
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    ABSTRACT: OBJECT The endoscopic fenestration of intraventricular CSF cysts has evolved into a well-accepted treatment modality. However, definition of the optimal trajectory for endoscopic fenestration may be difficult. Distorted ventricular anatomy and poor visibility within the cyst due to its contents can make endoscopic fenestration challenging if approached from the ipsilateral side. In addition, transcortical approaches can theoretically cause injury to eloquent cortex, particularly in patients with dominant-sided lesions. The aim of this study was to examine the value of the contralateral transcortical transventricular approach in patients with dominant-sided ventricular cysts. METHODS During a 5-year period between 2007 and 2011, 31 patients with intraventricular CSF cysts underwent surgery by the senior author (R.R.). Fourteen of these patients had cysts located on the dominant side. An image-guided endoscopic cyst fenestration via the contralateral transcortical transventricular approach was performed in 11 patients. A retrospective chart review was performed in all these patients to extract data on clinical presentation, operative technique, and surgical outcome. RESULTS The most common presenting symptom was headache, followed by memory deficits and cognitive deterioration. In all cases CSF cysts were space occupying, with associated obstructive hydrocephalus in 8 patients. Image-guided endoscopic fenestration was successfully performed in all cases, with septum pellucidotomy necessary in 6 cases, and endoscopic third ventriculostomy in 1 case for additional aqueductal occlusion. Postoperative clinical outcome was excellent, with no associated permanent neurological or neuropsychological morbidity. No recurrent cysts were observed over a mean follow-up period of 2 years and 3 months. CONCLUSIONS The contralateral approach to ventricular cysts can achieve excellent surgical outcomes while minimizing approach-related trauma to the dominant hemisphere. Careful case selection is essential to ensure that the contralateral endoscopic trajectory is the best possible exposure for sufficient cyst fenestration and restoration of CSF circulation.
    Journal of Neurosurgery 10/2015; DOI:10.3171/2015.4.JNS142157
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    ABSTRACT: OBJECT The object of this study was to determine the mortality and neurological outcome of patients with mild traumatic brain injury (mTBI) who require neurosurgical intervention (NSI), identify clinical predictors of a poor outcome, and investigate the effect of failed nonoperative management and delayed NSI on outcome. METHODS A cross-sectional study of 10 years was performed, capturing all adults with mTBI and NSI. Primary outcome variables were mortality and Glasgow Outcome Scale (GOS) score. Patients were divided into an immediate intervention group, which received an NSI after the initial cranial CT scan, and a delayed intervention group, which had failed nonoperative management and received an NSI after 2 or more cranial CT scans. RESULTS The mortality rate in mTBI patients requiring NSI was 13%, and the mean GOS score was 3.6 ± 1.2. An age > 60 years was independently predictive of a worse outcome, and epidural hematoma was independently predictive of a good outcome. Logistic regression analysis using independent variables was calculated to create a model for predicting poor neurological outcomes in patients with mTBI undergoing NSI and had 74.1% accuracy. Patients in the delayed intervention group had worse mortality (25% vs 9%) and worse mean GOS scores (2.9 ± 1.3 vs 3.7 ± 1.2) than those in the immediate intervention group. CONCLUSIONS Data in this study demonstrate that patients with mTBI requiring NSI have higher mortality rates and worse neurological outcomes and should therefore be classified separately from mTBI patients not requiring NSI. Additionally, mTBI patients requiring NSI after the failure of nonoperative management have worse outcomes than those receiving immediate intervention and should be considered separately.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2015.4.JNS142440
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    ABSTRACT: OBJECT The complication rate for cranioplasty after decompressive craniectomy is higher than that after other neurosurgical procedures; aseptic bone resorption is the major long-term problem. Patients frequently need additional operations to remove necrotic bone and replace it with an artificial bone substitute. Initial implantation of a bone substitute may be an option for selected patients who are at risk for bone resorption, but this cohort has not yet been clearly defined. The authors' goals were to identify risk factors for aseptic bone flap necrosis and define which patients may benefit more from an initial bone-substitute implant than from autograft after craniectomy. METHODS The authors retrospectively analyzed 631 cranioplasty procedures (503 with autograft, 128 with bone substitute) by using a stepwise multivariable logistic regression model and discrimination analysis. RESULTS There was a significantly higher risk for reoperation after placement of autograft than after placement of bone substitute; aseptic bone necrosis (n = 108) was the major problem (OR 2.48 [95% CI1.11-5.51]). Fragmentation of the flap into 2 or more fragments, younger age (OR 0.97 [95% CI 0.95-0.98]; p < 0.001), and shunt-dependent hydrocephalus (OR 1.73 [95% CI1.02-2.92]; p = 0.04) were independent risk factors for bone necrosis. According to discrimination analysis, patients younger than 30 years old and older patients with a fragmented flap had the highest risk of developing bone necrosis. CONCLUSIONS Development of bone flap necrosis is the main concern in long-term follow-up after cranioplasty with autograft. Patients younger than 30 years old and older patients with a fragmented flap may be candidates for an initial artificial bone substitute rather than autograft.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2015.4.JNS159
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    ABSTRACT: OBJECT This study explored whether there were differences between the autoimmune disease prevalence rates in unilateral and bilateral moyamoya disease (MMD). METHODS The authors performed a retrospective review of data obtained from the medical records of their hospital, analyzing and comparing the clinical characteristics and prevalence rates of all autoimmune diseases that were associated with unilateral and bilateral MMD in their hospital from January 1995 to October 2014. RESULTS Three hundred sixteen patients with bilateral MMD and 68 with unilateral MMD were identified. The results indicated that patients with unilateral MMD were more likely to be female than were patients with bilateral MMD (67.6% vs 51.3%, p = 0.014, odds ratio [OR] 1.99). Overall, non-autoimmune comorbidities tended to be more prevalent in the unilateral MMD cases than in the bilateral MMD cases (17.6% vs 9.8%, p = 0.063, OR 1.97, chi-square test). Autoimmune thyroid disease and other autoimmune diseases also tended to be more prevalent in the unilateral MMD cases than in the bilateral MMD cases (19.1% vs 10.8%, p = 0.056, OR 1.96 and 8.8% vs 3.5%, p = 0.092, OR 2.77, respectively, chi-square test). The overall autoimmune disease prevalence in the unilateral MMD cases was significantly higher than in the bilateral MMD cases (26.5% vs 13.6%, p = 0.008, OR 2.29, 95% CI 1.22-4.28, chi-square test). Multiple logistic regression analysis showed that autoimmune disease was more likely to be associated with unilateral than with bilateral MMD (p = 0.039, OR 10.91, 95% CI 1.13-105.25). CONCLUSIONS This study indicated a higher overall autoimmune disease prevalence in unilateral than in bilateral MMD. Unilateral MMD may be more associated with autoimmune disease than bilateral MMD. Different pathogenetic mechanisms may underlie moyamoya vessel formation in unilateral and bilateral MMD.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2015.4.JNS142936
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    ABSTRACT: OBJECT Lesioning of the dorsal root entry zone (DREZotomy) is an effective treatment for brachial plexus avulsion (BPA) pain. The role of preoperative assessment with MRI has been shown to be unreliable for determining affected levels; however, it may have a role in predicting pain outcomes. Here, DREZotomy outcomes are reviewed and preoperative MRI is examined as a possible prognostic factor. METHODS A retrospective review was performed of an institutional database of patients who had undergone brachial plexus DREZ procedures since 1995. Preoperative MRI was examined to assess damage to the DREZ or dorsal horn, as evidenced by avulsion of the DREZ or T2 hyperintensity within the spinal cord. Phone interviews were conducted to assess the long-term pain outcomes. RESULTS Between 1995 and 2012, 27 patients were found to have undergone cervical DREZ procedures for BPA. Of these, 15 had preoperative MR images of the cervical spine available for review. The outcomes were graded from 1 to 4 as poor (no significant relief), good (more than 50% pain relief), excellent (more than 75% pain relief), or pain free, respectively. Overall, DREZotomy was found to be a safe, efficacious, and durable procedure for relief of pain due to BPA. The initial success rate was 73%, which declined to 66% at a median follow-up time of 62.5 months. Damage to the DREZ or dorsal horn was significantly correlated with poorer outcomes (p = 0.02). The average outcomes in patients without MRI evidence of DREZ or dorsal horn damage was significantly higher than in patients with such damage (3.67 vs 1.75, t-test; p = 0.001). A longer duration of pain prior to operation was also a significant predictor of treatment success (p = 0.004). CONCLUSIONS Overall, the DREZotomy procedure has a 66% chance of achieving meaningful pain relief on long-term follow-up. Successful pain relief is associated with the lack of damage to the DREZ and dorsal horn on preoperative MRI.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2015.2.JNS142572
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    ABSTRACT: The object of this study was to analyze the pathology of collateral vessels newly induced by indirect bypass surgery for moyamoya disease (MMD). An autopsy analysis was conducted on a 39-year-old woman with MMD who had died of a brainstem infarction. The patient had undergone bilateral indirect bypass surgeries 22 years earlier. Sufficient revascularization via bilateral external carotid arterial systems was confirmed by cerebral angiography before her death. Macroscopic observation of the operative areas revealed countless meandering vessels on the internal surface of the dura mater connected with small vessels on the brain surface and in the subpial brain tissue. Notably, microscopic analysis of these vessels revealed the characteristic 3-layer structure of an arterial wall. This autopsy analysis was the first to confirm that indirect bypass surgery had induced the formation of a new arterial network (arteriogenesis) and that this network had been maintained for more than 20 years to compensate for the chronic cerebral ischemia caused by the MMD.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2015.4.JNS15155
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    ABSTRACT: OBJECT Treatment strategies for venous-predominant arteriovenous malformation (vp-AVM) remain unclear due to the limited number of cases and a lack of long-term outcomes. The purpose of this study was to report the authors' experience with treatment outcomes with a review of the pertinent literature in patients with vp-AVM. METHODS Medical and radiological data from 1998 to 2011 were retrospectively evaluated. The degree of the arteriovenous (AV) shunt was categorized into 2 groups, a high- and low-flow AV shunt based on the angiographic findings. RESULTS Sixteen patients with a mean age of 45.3 years (range 16-78 years) and a mean follow-up of 79.9 months (range 25-264 months) were examined. Symptomatic lesions were noted in 13 patients: intracranial hemorrhage (ICH) in 9, seizure in 1, and headache in 3. A high-flow shunt was observed on angiography in 13 patients. Among these 13 patients, 12 patients were symptomatic. Nine patients presenting with ICH underwent hematoma removal with additional Gamma Knife surgery (GKS; n = 4), GKS only (n = 2), or conservative treatment (n = 3). The 3 asymptomatic patients received conservative treatment, and 1 rebleeding episode was observed. Seven of 8 patients who underwent GKS as an initial or secondary treatment modality experienced a marked reduction in the AV shunt on follow-up angiography, but complete obliteration was not observed. CONCLUSIONS Poor lesion localization makes a vp-AVM challenging to treat. Symptomatic patients with a high-flow shunt are supposedly best treated with GKS, despite the fact that only 87.5% of the vp-AVMs treated this way showed a reduction in the malformation volume, and none were cured.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2015.4.JNS142475
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    ABSTRACT: OBJECT Neuroendoscopic surgery allows minimally invasive surgery, but lacks effective methods to control bleeding. Water jet dissection with continuous flow has been used in liver and kidney surgery since the 1980s, and is effective for tissue manipulation with vascular preservation, but involves some potential risks, such as elevation of intracranial pressure during application in the ventricles. The authors previously reported the efficacy of the actuator-driven pulsed water jet device (ADPJ) to dissect soft tissue with vascular preservation in microscopic neurosurgery. This feasibility study investigated the use of the ADPJ to reduce the amount of water usage, leading to more safety with sustained efficacy. METHODS A small-diameter pulsed water jet device was developed for use with the flexible neuroendoscope. To identify the optimal conditions for the water jet, the flow rate, water pressure, and distance between the nozzle and target were analyzed in an in vitro study by using a gelatin brain phantom. A ventricle model was used to monitor the internal pressure and temperature. For ex vivo experiments the porcine brain was harvested and ventricle walls were exposed, and subsequently immersed into physiological saline. For in vivo experiments the cortex was microsurgically resected to make the small cortico-ventricle window, and then the endoscope was introduced to dissect ventricle walls. RESULTS In the in vitro experiments, water pressure was approximately 6.5 bar at 0.5 mm from the ADPJ nozzle and was maintained at 1 mm, but dropped rapidly toward 50% at 2 mm, and became 10% at 3.5 mm. The ADPJ required less water to achieve the same dissection depth compared with the continuous-flow water jet. With the ventricle model, the internal pressure and temperature were well controlled at the baseline, with open water drainage. These results indicated that the ADPJ can be safely applied within the ventricles. The ADPJ was introduced into a flexible endoscope and the ventricle walls were dissected in both the ex vivo and in vivo conditions. The ventricle wall was dissected without obscuring the view, and the vascular structures were anatomically preserved under direct application. Histological examination revealed that both the vessels on the ventricle wall and the fine vessels in the parenchyma were preserved. CONCLUSIONS The ADPJ can safely and effectively dissect the ventricle wall, with vascular preservation in immersed conditions. To achieve the optimal result of tissue dissection with minimal surgical risk, the ADPJ is a potential device for neuroendoscopic surgery of the ventricles.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2015.3.JNS142121
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    ABSTRACT: OBJECT Predicting cognitive function following resective surgery remains an important clinical goal. Each MRI neuroimaging technique can potentially provide unique and distinct insight into changes that occur in the structural or functional organization of "at-risk" cognitive functions. The authors tested for the singular and combined power of 3 imaging techniques (functional MRI [fMRI], resting state fMRI, diffusion tensor imaging) to predict cognitive outcome following left (dominant) anterior temporal lobectomy for intractable epilepsy. METHODS The authors calculated the degree of deviation from normal, determined the rate of change in this measure across the pre- and postsurgical imaging sessions, and then compared these measures for their ability to predict verbal fluency changes following surgery. RESULTS The data show that the 3 neuroimaging techniques, in a combined model, can reliably predict cognitive outcome following anterior temporal lobectomy for medically intractable temporal lobe epilepsy. CONCLUSIONS These findings suggest that these 3 imaging modalities can be used effectively, in an additive fashion, to predict functional reorganization and cognitive outcome following anterior temporal lobectomy.
    Journal of Neurosurgery 09/2015; DOI:10.3171/2014.9.JNS131422