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Background: The severity of neurological deficits arising from ischemic stroke may be related to serum redox homeostasis. The aim of this study was to estimate the effect of serum paraoxonase (PON), arylesterase (ARE) activities and conjugated dienes (CD) on patient outcome during a 1-year follow-up period., Methods: The study included 468 consecutive ischemic stroke patients (251 males, 217 females) with an average age of 67.5 ± 12.4 years. Clinical evaluation was based on vital signs, National Institutes of Health Stroke Scale (NIHSS) scored at the time of admission and on the 7th day after stroke, as well as modified Rankin scale (mRS) and Barthel index (BI) scored at 30, 90, 180 and 360 days after stroke onset. Serum PON, ARE activities and CD concentration were measured with the use of spectrophotometric methods., Results: Serum PON activity alone correlated directly with a favorable outcome during a 3-month observation period. Serum ARE activity correlated directly only with the mRS score in a 1-year observation. PON/ARE ratio showed the strongest direct correlation with favorable stroke outcome expressed by BI and inverse correlation with mRS as compared to serum PON or ARE activities assessed alone. PON/ARE affected the NIHSS score on admission (rS = -0.119, p = 0.014) and on the 7th day after stroke (rS = 0.120, p = 0.015); it also showed an association with the BI and mRS on the 30th (rS = 0.145, p = 0.007 and rS = -0.098, p = 0.049, respectively), 90th (rS = 0.147, p = 0.009, rS = -0.133, p = 0.008, respectively), as well as 180th, and 360th day after stroke. We did not find correlations between the serum CD concentration and stroke outcome., Conclusion: The PON/ARE ratio is an important predictor of ischemic stroke outcome and can be used in clinical practice rather than evaluating either PON or ARE activity alone., (Copyright © 2011 S. Karger AG, Basel.)

This work addresses the spatial correlation between the anatomical and functional human subthalamic nucleus (STN). The anatomical STN (A-STN), derived from the Schaltenbrand-Wahren brain atlas, is histology based. The functional STN (F-STN) is probabilistic, constructed from neuroelectrophysiological and neuroimaging data of 184 Parkinson's disease patients. The A-STN and F-STN are placed in the same space and compared in terms of mutual relative overlapping of anatomy with function. The F-STN and A-STN correlate well for medium and high probabilities of the F-STN. For probability p >or= 0.3, >95% of F-STN is inside the A-STN, and for p >or= 0.5, the complete F-STN is inside the A-STN for each left and right STN. Therefore, the F-STN for p = 0.5 can potentially be used for identification of the STN in neuroimages., (Copyright (c) 2007 S. Karger AG, Basel.)

The Schaltenbrand-Wahren (SW) brain atlas has many limitations: the major two are three-dimensional (3D) inconsistency and spatial sparseness. In this work, we quantify and visualize the 3D inconsistency of the subthalamic nucleus (STN). The STN 3D models, 3D-A, 3D-C and 3D-S, are reconstructed from the SW axial, coronal, and sagittal microseries, respectively, by using a shape-based (NURBS) approach. All three models are placed in the SW coordinate system and compared quantitatively in terms of location (centroids), size (volumes), shape (normalized eigenvalues), orientation (eigenvectors), and mutual spatial relationships (overlaps and inclusions). Analysis is done in 3D within each orientation and across them. A dedicated tool is developed for quantitative validation of 3D modeling. The average error achieved is 0.088 mm, which is at the resolution limit of the digital SW atlas. The reconstructed 3D STN models differ in location, size, shape, orientation, overlap size, and inclusion rate. The 3D-S volume is 1.27 times larger than that of 3D-A and 1.38 times larger than that of 3D-C. The highest overlap size is found between 3D-A and 3D-S. The highest inclusion rates of 52.5 and 66.6% are for 3D-A and 3D-S. 3D-C has the lowest overlap size and results in the lowest inclusion rates (around 20-30%), meaning that 3D-C is substantially displaced in comparison to 3D-A and 3D-S. The lateral centroid coordinate of 3D-C is 9.18 mm while that of 3D-S is 12.17 mm. Each of the 3D models has some limitation: 3D-A in orientation, 3D-C in location, and 3D-S in shape realism. The STN in comparison to the actual almond is smaller, and relatively (i.e. normalized to the same height) 2.2-2.4 times wider and 3.7-5.5 times longer. 3D-C becomes more similar to 3D-S by scaling the SW coronal microseries laterally by 1.3257. Then the lateral coordinates of their centroids coincide, the difference between them in orientation is 0.11 mm, and 3D-S is only 1.06 times larger than the scaled 3D-C. This operation substantially improves registration of the SW atlas with the probabilistic functional atlas. However, 3D visualization shows that both 3D-S and scaled 3D-C models are heavily interwoven resulting in low inclusion rates of about 60%. The STN in the SW atlas shows severe 3D inaccuracy within each orientation and across them, and it has to be employed with great care and understanding of its limitations., (2006 S. Karger AG, Basel)

The major shortcomings of the Schaltenbrand-Wahren (SW) brain atlas include 3-dimensional (3D) inconsistency and spatial sparseness. This work quantifies and visualizes 3D inconsistency of the globus pallidus internus (GPi), a stereotactic target for the treatment of Parkinson's disease, dystonia and Huntington disease. The GPi 3D models 3D-A, 3D-C and 3D-S are reconstructed from the SW axial, coronal and sagittal microseries, respectively, by applying a shape-based (Nonuniform Rational B Splines) method. All three 3D models, placed in the SW coordinate system, are compared quantitatively in terms of location (centroids), size (volumes), shape (normalized eigen values), orientation (eigen vectors) and mutual spatial relationships (overlaps and inclusions). The analysis is done in 3D within each orientation and across them. The reconstructed 3D GPi models substantially differ in location, size and inclusion rate. The centroid of 3D-C is located more medially (15.6 mm) than those of 3D-A (17.5 mm) and 3D-S (18.2 mm), and that of 3D-A more ventrally (-2.3 mm) than those of 3D-C (-0.1 mm) and 3D-S (-0.4 mm). 3D-S has the smallest volume (347.3 mm3); 3D-A is 1.18 and 3D-C 1.85 times larger. The highest inclusion rate is for 3D-S (54.3 and 56.3%) and the lowest for 3D-C (28.8 and 30.6%). A smaller variability is observed in shape, orientation and overlap size (196.8, 196.1 and 185.5 mm3). To get a better correspondence between 3D-C and 3D-S, the coronal microseries were scaled laterally by 1.1667. This results in a substantial improvement of the inclusion rate of 3D-S (87.9%), though raising the volume mismatch to 2.16. The GPi in the SW atlas has a substantial 3D inaccuracy within each orientation and across them. Therefore, absolute and direct reliance on the original atlas is unsafe, and this atlas has to be used with great care and understanding of its limitations. As matching various SW microseries by global scaling is not feasible, we propose the target-dependent scaling based on structure centroid matching., (Copyright 2006 S. Karger AG, Basel.)

We have previously introduced a concept of a probabilistic functional atlas (PFA) to overcome limitations of the current electronic stereotactic brain atlases: anatomical nature, spatial sparseness, inconsistency and lack of population information. The PFA for the STN has already been developed. This work addresses construction of the PFA for the ventrointermediate nucleus (PFA-VIM). The PFA-VIM is constructed from pre-, intra- and postoperative electrophysiological and neuroimaging data acquired during the surgical treatment of Parkinson's disease patients. The data contain the positions of the chronically implanted electrodes and their best contacts. For each patient, the intercommissural distance, height of the thalamus and width of the third ventricle were measured. An algorithm was developed to convert these data into the PFA-VIM, and to present them on axial, coronal and sagittal planes and in 3-D. The PFA-VIM gives a spatial distribution of the best contacts, and its probability is proportional to best contact concentration in a given location. The region with the highest probability corresponds to the best target. The PFA-VIM is calculated with 0.25-mm3 resolution from 107 best contacts in two situations: with and without lateral compensation against the width of the third ventricle. For the PFA-VIM compensated laterally, the anterior, lateral and dorsal coordinates of the mean value are (in mm) 6.24, 13.83, 1.68 for the left VIM and 6.54, -13.84, 2.10 for the right VIM. The coordinates of the mean value of the highest probability region along with the highest number of the best contacts (P) are: 6.25, 14.25, 1.75, P = 16, for the left VIM, and 6.0, -14.0, 1.00, P = 18, for the right VIM. The coordinate system origin is at the posterior commissure. For the PFA-VIM not compensated laterally, the coordinates of the mean value are 6.24, 13.99, 1.68 for the left VIM and 6.53, -14.13, 2.10 for the right VIM. The coordinates of the mean value of the highest probability region along with the highest number of the best contacts are 5.58, 13.67, 1.33, P = 14, for the left VIM, and 6.36, -14.03, 1.11, P = 17, for the right VIM. The PFA-VIM atlas overcomes several limitations of the current anatomical atlases and can improve targeting of thalamotomies and thalamic stimulations. It is dynamic and can easily be extended with new cases., (2005 S. Karger AG, Basel.)

Objective: The Schaltenbrand-Wahren atlas (SWA) is anatomical, sparse and inconsistent in three dimensions. A high-resolution, electrophysiology-based atlas derived from numerous specimens overcomes these limitations. A combined anatomy-physiology atlas leverages the strengths and complementarity of both, which is studied here., Method: An electronic version of the SWA was constructed. A probabilistic functional atlas (PFA) was developed from electrophysiological and neuroimaging data with 0.25 mm3 resolution. A combined atlas is constructed by co-registering the PFA with the SWA by applying linear scaling along the intercommissural distance and the height of the thalamus., Results: An anatomy-physiology atlas is superior to its component atlases. When in register, the anatomical and functional atlases are displayed together and used simultaneously. A structure of interest from the PFA can be displayed with high resolution, compensating for its sparseness in the SWA, while its surrounding structures are obtained from the SWA. The best anatomical and functional targets can be compared: for the subthalamic nucleus, the horizontal and lateral coordinates of the SWA-based and PFA- based targets are approximately the same, while the latter is located 1.3-1.5 mm more anteriorly., Conclusion: An anatomy-physiology atlas may enhance the accuracy of targeting and increase the neurosurgeon's confidence. It also opens new research avenues to serve as a reference for: (1) constructing an extendable atlas by adding new electrophysiological data, (2) comparing anatomical and functional targets, (3) studying and comparing various symptoms, and (4) comparing image-based targets obtained from various modalities., (2004 S. Karger AG, Basel.)

Objective: This paper describes an Internet portal for stereotactic and functional neurosurgery with a probabilistic functional atlas (PFA) calculated from electrophysiological and neuroimaging data. This portal enables (1) data sharing among neurosurgeons; (2) the calculation of probabilistic functional maps of stereotactic target structures from a neurosurgeon's own data, optionally combined with data from other neurosurgeons, and (3) the construction and development of a PFA of the human brain by the neurosurgical community via the Internet., Method: The overall approach is done in three steps: (1) development and validation of the algorithm for PFA generation; (2) design and development of the portal for stereotactic and functional neurosurgery with tools for the rapid calculation, presentation, and use of the PFA, and (3) portal testing with the initial data acquired for 274 Parkinson's disease patients, 487 hemispheres, and 500 best contacts. This paper covers step 2 and some results from step 3., Results: The Internet portal has been developed in Java and tested with the available data. Functions have been developed for: (1) data input, transfer, and editing; (2) data selection for PFA generation; (3) PFA generation; (4) PFA display and interactive manipulation, and (5) target planning. The portal has been put on the Internet for public use and so far more than 100 users downloaded it., Conclusion: The Internet portal for stereotactic and functional neurosurgery with a PFA potentially increases both the accuracy of targeting and the neurosurgeon's confidence. The portal may be useful for both experienced functional neurosurgeons who have studied numerous cases and novices in the field. The use of the PFA through this portal, and sharing and expanding its content by neurosurgeons represents a paradigm shift from manufacturer centric to community centric., (Copyright 2002 S. Karger AG, Basel)

This paper presents a novel approach for the use of the Atlas for Stereotaxy of the Human Brain by Schaltenbrand and Wahren [Stuttgart, Thieme, 1977] for anatomical targeting in functional neurosurgery. We propose to use simultaneously all three electronic axial, coronal and sagittal mutually coregistered Schaltenbrand-Wahren brain atlas microseries. The printed atlas microseries are digitized, extended to cover both hemispheres, contoured, labeled, organized into atlas volumes, and mutually coregistered. The electronic atlas is interactively registered with the data by using the three-dimensional Talairach proportional grid system transformation, followed up by local warping in the region of interest based on any clearly visible landmarks. The detailed targeting steps for pallidotomy, thalamotomy and subthalamotomy are formulated. The potential of this approach is to increase the accuracy of target definition, to decrease the time of the procedure by reducing the number of microelectrode tracts, and to give an extra degree of confidence to the neurosurgeon. The advantages of the approach and the limitations of the Schaltenbrand-Wahren atlas are discussed.