19 research outputs found

    Predicting Stock Market using Regression Technique

    Get PDF
    We use two and half year data set of 50 companies of Nifty along with Nifty from 1st Jan 2009 to 28th June 2011 and apply multivariate technique for data reduction, namely Factor Analysis. Using Factor analysis we reduce these 50 companies’ data (50 variables) into the most significant 4 FACTORS. These four significant factors are then used to predict the Nifty using Multiple linear regression. We observed that the model is good fitted and it explained 90 % of the total variance. Keywords: Nifty, Factor Analysis, Multiple Linear Regression, Data reduction

    Posterior Interhemispheric Transfalcine Transprecuneus Approach for Microsurgical Resection of Peri-Atrial Lesions: Indications, Technique, and Outcomes

    Get PDF
    OBJECT Surgical exposure of the peritrigonal or periatrial region has been challenging due to the depth of the region and overlying important functional cortices and white matter tracts. The authors demonstrate the operative feasibility of a contralateral posterior interhemispheric transfalcine transprecuneus approach (PITTA) to this region and present a series of patients treated via this operative route. METHODS Fourteen consecutive patients underwent the PITTA and were included in this study. Pre- and postoperative clinical and radiological data points were retrospectively collected. Complications and extent of resection were reviewed. RESULTS The mean age of patients at the time of surgery was 39 years (range 11–64 years). Six of the 14 patients were female. The mean duration of follow-up was 4.6 months (range 0.5–19.6 months). Pathology included 6 arteriovenous malformations, 4 gliomas, 2 meningiomas, 1 metastatic lesion, and 1 gray matter heterotopia. Based on the results shown on postoperative MRI, 1 lesion (7%) was intentionally subtotally resected, but ≥ 95% resection was achieved in all others (93%) and gross-total resection was accomplished in 7 (54%) of 13. One patient (7%) experienced a temporary approach-related complication. At last follow-up, 1 patient (7%) had died due to complications of his underlying malignancy unrelated to his cranial surgery, 2 (14%) demonstrated a Glasgow Outcome Scale (GOS) score of 4, and 11 (79%) manifested a GOS score of 5. CONCLUSIONS Based on this patient series, the contralateral PITTA potentially offers numerous advantages, including a wider, safer operative corridor, minimal need for ipsilateral brain manipulation, and better intraoperative navigation and working angles

    Proton therapy for atypical meningiomas

    Get PDF
    We report clinical outcomes of proton therapy in patients with World Health Organization grade 2 (atypical) meningiomas. Between 2005 and 2013, 22 patients with atypical meningiomas were treated to a median dose of 63 Gy (RBE) using proton therapy, as an adjuvant therapy after surgery (n = 12) or for recurrence or progression of residual tumor (n = 10). Six patients had presumed radiation-induced meningiomas, but none had received prior radiotherapy for their meningioma. The median follow-up time after radiation was 39 months (range 7–104) and all patients remain alive at last follow-up. The 5-year estimate of local control was 71.1 % (95 % CI 49.3–92.9 %). The 5-year estimate of local control was 87.5 % following a radiation dose >60 Gy (RBE), compared to 50.0 % for ≤60 Gy (RBE) (p = 0.038). The 5-year estimate of neuraxis dissemination was 5 % (95 % CI 0–14.6 %) and 6.2 % (95 % CI 0–18.2 %) for metastases outside of the central nervous system. Radiation necrosis was observed in one patient with a history of prior cranial irradiation. Fractionated proton therapy was associated with favorable tumor control rates for grade 2 meningiomas. Prospective studies are needed to define the optimal radiation dose for high-grade meningiomas

    Intracranial chordoma presenting as acute hemorrhage in a child: Case report and literature review

    Get PDF
    BACKGROUND: Chordomas are rare, slow-growing malignant neoplasms derived from remnants of the embryological notochord. Pediatric cases comprise only 5% of all chordomas, but more than half of the reported pediatric chordomas are intracranial. For patients of all ages, intracranial chordomas typically present with symptoms such as headaches and progressive neurological deficits occurring over several weeks to many years as they compress or invade local structures. There are only reports of these tumors presenting acutely with intracranial hemorrhage in adult patients. CASE DESCRIPTION: A 10-year-old boy presented with acute onset of headache, emesis, and diplopia. Head computed tomography and magnetic resonance imaging of brain were suspicious for a hemorrhagic mass located in the left petroclival region, compressing the ventral pons. The mass was surgically resected and demonstrated acute intratumoral hemorrhage. Pathologic examination was consistent with chordoma. CONCLUSION: There are few previous reports of petroclival chordomas causing acute intracranial hemorrhage. To the authors' knowledge, this is the first case of a petroclival chordoma presenting as acute intracranial hemorrhage in a pediatric patient. Although uncommon, it is important to consider chordoma when evaluating a patient of any age presenting with a hemorrhagic lesion of the clivus

    Intraoperative detection of isocitrate dehydrogenase mutations in human gliomas using a miniature mass spectrometer

    Get PDF
    Knowledge of the isocitrate dehydrogenase (IDH) mutation status of glioma patients could provide insights for decision-making during brain surgery. However, pathology is not able to provide such information intraoperatively. Here we describe the first application of a miniature mass spectrometer (MS) to the determination of IDH mutation status in gliomas intraoperatively. The instrumentation was modified to be compatible with use in the operating room. Tandem MS was performed on the oncometabolite, 2-hydroxyglutarate, and a reference metabolite, glutamate, which is not involved in the IDH mutation. Ratios of fragment ion intensities were measured to calculate an IDH mutation score, which was used to differentiate IDH mutant and wild-type tissues. The results of analyzing 25 biopsies from 13 patients indicate that reliable determination of IDH mutation status was achieved (p = 0.0001, using the Kruskal-Wallis non-parametric test). With its small footprint and low power consumption and noise level, this application of miniature mass spectrometers represents a simple and cost-effective platform for an important intraoperative measurement

    Validated stability-indicating high performance thin layer chromatographic method for determination of Ivabradine hydrochloride in bulk and marketed formulation: An application to kinetic study

    Get PDF
    A sensitive, selective, precise and accurate stability-indicating high-performance thin layer chromatographic method for analysis of Ivabradine hydrochloride (IH) an anti anginal agent, both as a bulk drug and in formulations was developed and validated according to ICH guideline. Densitometric analysis of IH was carried out in the absorbance mode at 287 nm using ethyl acetate: 0.389 M ammonium acetate in methanol (1:5, v/v) as solvent system. This system was found to give compact spots for IH at an Rf value of 0.36 ± 0.01. Moreover, IH was subjected to acid and alkali hydrolysis, oxidation, accelerated humidity/temperature, wet heat treatment, and photo degradation. The drug undergoes degradation under mainly acidic and basic conditions. Also the degraded products were well resolved from the pure drug with significantly different Rf values. Linearity was found to be in the range of 1200–2800 ng/band. The LOD and LOQ for IH were 255.86 ng/band and 775.33 ng/band, respectively. “Bartlett’s test” and “Lack of fit” applied on peak area for linearity, additionally proved validity of the developed method. Good accuracy and precision were obtained as revealed from %RSD value less than 2. Similarly, no interference was observed from common excipients in tablet formulation as well as degradation product, indicating specificity of the method. As the method could effectively separate the drug from its degradation product, it can be employed as a stability-indicating one. Moreover, proposed method was also utilized to investigate the kinetics of acidic degradation process at different temperatures and first order rate constant, half-life, shelf-life and activation energy were calculated

    Minimally-invasive transsulcal resection of intraventricular and periventricular lesions through a tubular retractor system: Multicentric experience and results

    Get PDF
    BACKGROUND: Conventional approaches to deep-seated cerebral lesions range from biopsy to trans-cortical or trans-callosal resection. While the former doesn\u27t reduce tumor burden, the latter are more invasive and associated with greater potential for irreparable injury to normal brain. Disconnection syndrome, hemiparesis, hemi-anesthesia or aphasia is not uncommon after such surgery, especially when lesion is large. By contrast, the trans-sulcal parafascicular approach utilizes naturally existing corridors and employs a tubular retractor to minimize brain injury. METHODS: A retrospective review of patients undergoing minimally invasive trans-sulcal parafascicular resection of ventricular and periventricular lesions, across 5 independent centers, were conducted. RESULTS: Twenty patients with lesions located in the lateral ventricle (n=9), the third ventricle (n=6) and periventricular region (n=4) are described in this report. Average age was 64 years (8M/12F). Average depth from cortical surface was 4.37 cm. A 13.5 mm diameter tubular retractor (Brainpath, NICO Corporation, Indianapolis, IN) of differing lengths was employed, aided by neuro-navigation. Gross-total resection was obtained in 17 patients. Pathologies included colloid cyst, subependymoma, glioma, meningioma, central neurocytoma, lymphoma and metastasis. Three patients experienced transient morbidity: memory loss (2), hemiparesis (1). One patient died 2 months postoperatively due to unrelated pulmonary illness. Follow-up ranged form 6 to 27 months (average 12 months). CONCLUSION: This technique is safe and effective for the treatment of intraventricular and periventricular lesions. Surgery-related morbidity is minimal and often transient. Lesions are satisfactorily resected and residuum occur when neoplasm involves vital structures. The tubular retractor minimizes trauma to brain incident on the surgeon\u27s path

    The Safety and Feasibility of Image-Guided BrainPath-Mediated Transsulcul Hematoma Evacuation: A Multicenter Study.

    No full text
    BACKGROUND: Subcortical injury resulting from conventional surgical management of intracranial hemorrhage may counteract the potential benefits of hematoma evacuation. OBJECTIVE: To evaluate the safety and potential benefits of a novel, minimally invasive approach for clot evacuation in a multicenter study. METHODS: The integrated approach incorporates 5 competencies: (1) image interpretation and trajectory planning, (2) dynamic navigation, (3) atraumatic access system (BrainPath, NICO Corp, Indianapolis, Indiana), (4) extracorporeal optics, and (5) automated atraumatic resection. Twelve neurosurgeons from 11 centers were trained to use this approach through a continuing medical education-accredited course. Demographical, clinical, and radiological data of patients treated over 2 years were analyzed retrospectively. RESULTS: Thirty-nine consecutive patients were identified. The median Glasgow Coma Scale (GCS) score at presentation was 10 (range, 5-15). The thalamus/basal ganglion regions were involved in 46% of the cases. The median hematoma volume and depth were 36 mL (interquartile range [IQR], 27-65 mL) and 1.4 cm (IQR, 0.3-2.9 cm), respectively. The median time from ictus to surgery was 24.5 hours (IQR, 16-66 hours). The degree of hematoma evacuation was ≥90%, 75% to 89%, and 50% to 74% in 72%, 23%, and 5.0% of the patients, respectively. The median GCS score at discharge was 14 (range, 8-15). The improvement in GCS score was statistically significant (P \u3c .001). Modified Rankin Scale data were available for 35 patients. Fifty-two percent of those patients had a modified Rankin Scale score of ≤2. There were no mortalities. CONCLUSION: The approach was safely performed in all patients with a relatively high rate of clot evacuation and functional independence. ABBREVIATIONS: AVM, arteriovenous malformationCLEAR II, Clot Lysis Evaluating Accelerated Resolution of IVH Phase IIDTI, diffusion tensor imagingGCS, Glasgow Coma ScaleICH, intracranial hemorrhageIQR, interquartile rangeIVH, intraventricular hemorrhageMIS, minimally invasive surgeryMISPACE, minimally invasive subcortical parafascicular access for clot evacuationMISTIE, Minimally Invasive Surgery and rt-PA in Intracerebral Hemorrhage EvacuationmRS, modified Rankin Scale
    corecore