Name: dti of the visual pathway - white matter tracts and cerebral lesions
Uploaded: 2014-08-26T15:00:00
Description: Watch this Scientific Journal Video about DTI of the Visual Pathway - White Matter Tracts and Cerebral Lesions at JoVE.com

We would like to thank the whole Service of Neuroradiology. We would like to thank Lis Prussen for her work in the library.

OBS: Detta protokoll följer riktlinjerna i Centre Hospitalier de Luxembourg i Luxemburg. 1 Beredning av Diffusion Tensor Imaging för Visual Pathway för neurokirurgi och Uppföljning <ol style="margin-left: 40px;"><li> Utför en MR-skanning minst en dag före operation strikt axiellt med hjälp av 32 gradient riktningar och en b0-image. Håll nära kontakt med neuroradiologi enhet som helst. OBS: Se klart för neuroradiologist att bilderna efter operation är desamma som före ope...

<ol>
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C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intraoperative+High-Field+Magnetic+Resonance+Imaging+Combined+With+Fiber+Tract+Neuronavigation-Guided+Resection+of+Cerebral+Lesions+Involving+Optic+Radiation.">Intraoperative High-Field Magnetic Resonance Imaging Combined With Fiber Tract Neuronavigation-Guided Resection of Cerebral Lesions Involving Optic Radiation.</a> Neurosurgery. 69 (5), 1070-1084 (2011).</li><li>Kamada, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+Monitoring+For+Visual+Pathway+Using+Real-Time+Visual+Evoked+Potentials+Aand+Optic-Radiation+Tractography.">Functional Monitoring For Visual Pathway Using Real-Time Visual Evoked Potentials Aand Optic-Radiation Tractography.</a> Neurosurgery. 57 (1 Suppl), 121-127 (2005).</li><li>Wu, W., Rigolo, L., O'Donnell, L. 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O., Giordano, M., Raabe, A., Fahlbusch, R., Samii, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optic+Radiation+Fiber+Tracking+Using+Anteriorly+Angulated+Diffusion+Tensor+Imaging:+A+Tested+Algorithm+for+Quick+Application.">Optic Radiation Fiber Tracking Using Anteriorly Angulated Diffusion Tensor Imaging: A Tested Algorithm for Quick Application.</a> Neurosurgery. 68 (5), 1239-1251 (2011).</li><li>Hodaie, M., Quan, J., Chen, D. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Vivo+Visualization+of+Cranial+Nerve+Pathways+in+Humans+Using+Diffusion-Based+Tractography.">In Vivo Visualization of Cranial Nerve Pathways in Humans Using Diffusion-Based Tractography.</a> Neurosurgery. 66 (4), 788-795 (2010).</li><li>Perrin, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fiber+tracking+in+Q-ball+fields+using+regularized+particle+trajectories.">Fiber tracking in Q-ball fields using regularized particle trajectories.</a> Inf Process Med Imaging. 19, 52-63 (2005).</li><li>Wedeen, V. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diffusion+spectrum+magnetic+resonance+imaging+(DSI)+tractography+of+crossing+fibers.">Diffusion spectrum magnetic resonance imaging (DSI) tractography of crossing fibers.</a> Neuroimage. 41 (4), 1267-1277 (2008).</li><li>Yamamoto, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diffusion+Tensor+Fiber+Tractography+of+the+Optic+Radiation:+Analysis+with+6-,+12-,+40-,+and+81-+Directional+Motion-Probing+Gradients,+a+Preliminary+Study.">Diffusion Tensor Fiber Tractography of the Optic Radiation: Analysis with 6-, 12-, 40-, and 81- Directional Motion-Probing Gradients, a Preliminary Study.</a> AJNR Am J Neuroradiol. 28 (1), 92-96 (2007).</li><li>Okada, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diffusion+Tensor+Fiber+Tractography+for+Arteriovenous+Malformations:+Quantitative+Analyses+to+Evaluate+the+Corticospinal+Tract+and+Optic+Radiation.">Diffusion Tensor Fiber Tractography for Arteriovenous Malformations: Quantitative Analyses to Evaluate the Corticospinal Tract and Optic Radiation.</a> AJNR Am J Neuroradiol. 28 (6), 1107-1113 (2007).</li><li>Kuhnt, D., Bauer, M. H., Sommer, J., Merhof, D., Nimsky, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optic+Radiation+Fiber+Tractography+in+Glioma+Patients+Based+on+High+Angular+Resolution+Diffusion+Imaging+with+Compressed+Sensing+Compared+with+Diffusion+Tensor+Imaging+-+Initial+Experience.">Optic Radiation Fiber Tractography in Glioma Patients Based on High Angular Resolution Diffusion Imaging with Compressed Sensing Compared with Diffusion Tensor Imaging - Initial Experience.</a> PLoS One. 8 (7), e70973 (2013).</li><li>Basser, P. J., Pajevic, S., Pierpaoli, C., Duda, J., Aldroubi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+fiber+tractography+using+DT-MRI+data.">In vivo fiber tractography using DT-MRI data.</a> Magn Reson Med. 44 (4), 625-632 (2000).</li><li>Friman, O., Farneback, G., Westin, C. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Bayesian+approach+for+stochastic+white+matter+tractography.">A Bayesian approach for stochastic white matter tractography.</a> IEEE Trans Med Imaging. 25 (8), 965-978 (2006).</li><li>Mori, S., van Zijl, P. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fiber+tracking:+principles+and+strategies+-+a+technical+review.">Fiber tracking: principles and strategies - a technical review.</a> NMR Biomed. 15 (7-8), 468-480 (2002).</li><li>Alexander, D. C., Barker, G. J., Arridge, S. 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DTI är en teknik som gör det möjligt neurokirurgen att visualisera vita substans in vivo 8. Den visuella vägen är ett av dessa områden. Även om denna metod ger läkare med nya möjligheter när det gäller behandling av patienter med skador om vältaliga regioner i hjärnan som vi måste säga att vissa begränsningar av denna teknik gör fortfarande existerar. Den första och mest uppenbara utmaningen är hjärn skift, vilket fortfarande är en fråga som utreds 4. Efter att ha öp...

Diffusion tensor imaging (DTI) används för att skildra WMT icke-invasivt i den mänskliga hjärnan 1. Det har använts i de senaste tio åren för att minska risken för att skada elokventa områden av hjärnan under operation en. DTI utfördes i femtio patienter mellan mars 2012 och januari 2014 för att beskriva den visuella vägen. DTI kan förbättra bevarandet av vältaliga områden i hjärnan under operationen genom att ge viktig information om den anatomiska placeringen av vita substans. Det har införlivats i den strategiska planeringen för resektion av komplexa hjärnskador 1. Dock fortfarande skildringen av den visuella vägen en utmaning eftersom det inte finns någon standard för parametrarna för DTI, placeringen av volymerna utsäde och tolkning av resultat 12. Olika algoritmer har genomförts hittills 19-21. Vissa metoder koncentrerade på deterministiska metoder 19, 22-25. Andra använde probabilistiska metoder, 26,27,29. På senare tid, till tekniker som använder Q-ball tensor fält, diffusion spektral avbildning och hög Vinkelupplösning Diffusion Imaging (HARDI) används skildra vita substans bland annat den visuella pathway 1,13-15,18. Ändå är den tid som krävs för HARDI betydligt längre med 45 min, är programvaran inte är kommersiellt tillgänglig och betonar vetenskapliga applikationer 18. Undervisningen Perioden för HARDI verkar vara längre än för DTI 18. Den presenterade protokollet är lätt genomförbar och kan användas för daglig rutin i neurokirurgiska ingrepp för att undvika sjuklighet och förbättra den postoperativa resultatet. Den extra tid för detta protokoll är mindre än 9 min vilket är betydligt snabbare än andra protokoll 1,9,12,16. Erkänner att många sofistikerade algoritmer har nyligen utvecklats pappers begränsarsig till användning av en kommersiellt tillgänglig och FDA-godkänd programvara. Men det är obligatoriskt att ta hänsyn till de begränsningar av denna teknik som nämns ovan.

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dti of the visual pathway - white matter tracts and cerebral lesions

<html> DTI är en teknik som identifierar vita substans (WMT) icke-invasivt på friska och icke-friska patienter som använder diffusion mätningar. Liknar visuella vägar (VP), WMT är inte synliga med klassisk MR eller intraoperativt med mikroskop. DIT hjälper neurokirurger att förhindra förstörelse av VP och ta av lesioner intill denna WMT. Vi har utfört DTI på femtio patienter före och efter operation mellan mars 2012 till januari 2014 Så här navigerar vi använt en 3DT1 Vägt sekvens. Dessutom genomförde vi en T2-viktade och DTI-sekvenser. De parametrar som användes var, FOV: 200 x 200 mm, skivtjocklek: 2 mm, och förvärvs matris: 96 x 96 vilket ger nästan isotropa voxlar av 2 x 2 x 2 mm. Axiell MRI utfördes med användning av en 32 gradient riktning och en b0-bild. Vi använde Echo-Planar-Imaging (EPI) och ASSET parallell avbildning med en accelerationsfaktor 2 b-värde på 800 s / mm. Den sveptiden var mindre än 9 min. ent &quot;&gt; DTI-data som erhållits bearbetades med hjälp av en FDA godkänt kirurgiskt navigationssystem program som använder en enkel fiber-tracking metod som kallas fiber uppdrag genom kontinuerlig tracking (FACT). Detta baseras på utbredningen av linjer mellan regioner av intresse ( ROI) som definieras av en läkare. En maximal vinkel på 50, FA startvärde av 0,10 och ADC stoppvärde av 0,20 mm ^ / s var de parametrar som används för tractography. Det finns vissa begränsningar för denna teknik. Den begränsade förvärvs tid upprätt kompromisser i bildkvalitet. En annan viktig punkt som inte bör försummas är hjärnan skift under operation. När det gäller den sistnämnda intraoperativ MR kan vara till hjälp. Dessutom risken för falska positiva eller falska negativa områden måste tas med i beräkningen, som kan äventyra de slutliga resultaten.

<html> Detta protokoll gör det möjligt för läkaren att skildra ett adekvat sätt de stora delarna av VP. Den kan användas med en liten mängd tid i syfte att förhindra skador hos patienter med cerebral lesioner bredvid elokventa områden. Postoperativa kontroller visar också goda resultat. VP skildras i figur 7 efter det att patienten var i drift från en glioblastom. Figur 2 visar VP efter återfall av en glioblastom. Författarna erkänner det faktum att de svårigheter som dett...

Watch this Scientific Journal Video about DTI of the Visual Pathway - White Matter Tracts and Cerebral Lesions at JoVE.com

DTI of the Visual Pathway - White Matter Tracts and Cerebral Lesions

Diffusion tensor imaging (DTI) utfördes för att försöka skildra de viktigaste delarna av den visuella vägen. Målet var att använda en FDA godkänd standard kommersiell arbetsstation som skulle kunna användas för daglig rutin för att försöka minska postoperativa skador av den visuella vägen hos patienterna.

DTI av Visual Pathway - vita substans och Cerebral lesioner

DTI is a technique that identifies white matter tracts (WMT) non-invasively in healthy and non-healthy patients using diffusion measurements. Similar to ...

dti-of-the-visual-pathway-white-matter-tracts-and-cerebral-lesions

Research

JoVE Journal

Medicine

The Application Of Permanent Middle Cerebral Artery Ligation in the Mouse

Focal cerebral ischemia is among the most common type of stroke seen in patients. Due to the clinical significance there has been a prolonged effort to develop suitable animal models to study the events that unfold during ischemic insult. These techniques include transient or permanent, focal or global ischemia models using many different animal models, with the most common being rodents.
The permanent MCA ligation method which is also referred as pMCAo in the literature is used extensively as a focal ischemia model in rodents 1-6. This method was originally described for rats by Tamura et al. in 1981 7. In this protocol a craniotomy was used to access the MCA and the proximal regions were occluded by electrocoagulation. The infarcts involve mostly cortical and sometimes striatal regions depending on the location of the occlusion. This technique is now well established and used in many laboratories 8-13. Early use of this technique led to the definition and description of &#x201C;infarct core&#x201D; and &#x201C;penumbra&#x201D; 14-16, and it is often used to evaluate potential neuroprotective compounds 10, 12, 13, 17. Although the initial studies were performed in rats, permanent MCA ligation has been used successfully in mice with slight modifications 18-20 .
This model yields reproducible infarcts and increased post-survival rates. Approximately 80% of the ischemic strokes in humans happen in the MCA area 21 and thus this is a very relevant model for stroke studies. Currently, there is a paucity of effective treatments available to stroke patients, and thus there is a need for good models to test potential pharmacological compounds and evaluate physiological outcomes. This method can also be used for studying intracellular hypoxia response mechanisms in vivo. 
Here, we present the MCA ligation surgery in a C57/BL6 mouse. We describe the pre-surgical preparation, MCA ligation surgery and 2,3,5 Triphenyltetrazolium chloride (TTC) staining for quantification of infarct volumes.

Middle cerebral artery (MCA) ligation is a technique to study focal cerebral ischemia in animal models. In this method, the middle cerebral artery is exposed by craniotomy and ligated by cauterization. This method gives highly reproducible infarct volumes and increased post-operative survival rates compared to other methods available.

Tillämpningen av permanenta Mellanöstern Cerebral Artery Ligation i musen

Focal cerebral ischemia is among the most common type of stroke seen in patients. Due to the clinical significance there has been a prolonged effort to ...

Driving Simulation in the Clinic: Testing Visual Exploratory Behavior in Daily Life Activities in Patients with Visual Field Defects

Patients suffering from homonymous hemianopia after infarction of the posterior cerebral artery (PCA) report different degrees of constraint in daily life, despite similar visual deficits. We assume this could be due to variable development of compensatory strategies such as altered visual scanning behavior. Scanning compensatory therapy (SCT) is studied as part of the visual training after infarction next to vision restoration therapy. SCT consists of learning to make larger eye movements into the blind field enlarging the visual field of search, which has been proven to be the most useful strategy1, not only in natural search tasks but also in mastering daily life activities2. Nevertheless, in clinical routine it is difficult to identify individual levels and training effects of compensatory behavior, since it requires measurement of eye movements in a head unrestrained condition. Studies demonstrated that unrestrained head movements alter the visual exploratory behavior compared to a head-restrained laboratory condition3. Martin et al.4 and Hayhoe et al.5 showed that behavior demonstrated in a laboratory setting cannot be assigned easily to a natural condition. Hence, our goal was to develop a study set-up which uncovers different compensatory oculomotor strategies quickly in a realistic testing situation: Patients are tested in the clinical environment in a driving simulator. SILAB software (Wuerzburg Institute for Traffic Sciences GmbH (WIVW)) was used to program driving scenarios of varying complexity and recording the driver's performance. The software was combined with a head mounted infrared video pupil tracker, recording head- and eye-movements (EyeSeeCam, University of Munich Hospital, Clinical Neurosciences).
The positioning of the patient in the driving simulator and the positioning, adjustment and calibration of the camera is demonstrated. Typical performances of a patient with and without compensatory strategy and a healthy control are illustrated in this pilot study. Different oculomotor behaviors (frequency and amplitude of eye- and head-movements) are evaluated very quickly during the drive itself by dynamic overlay pictures indicating where the subjects gaze is located on the screen, and by analyzing the data. Compensatory gaze behavior in a patient leads to a driving performance comparable to a healthy control, while the performance of a patient without compensatory behavior is significantly worse. The data of eye- and head-movement-behavior as well as driving performance are discussed with respect to different oculomotor strategies and in a broader context with respect to possible training effects throughout the testing session and implications on rehabilitation potential.

Patients with visual deficits after stroke report about different constraints in daily life most likely due to variable compensatory strategies, which are difficult to differentiate in clinical routine. We present a clinical set-up which allows measurement of different compensatory head- and eye-movement-strategies and evaluating their effects on driving performance.

Körning Simulering på kliniken: Testa Visual undersökande beteende i vardagliga sysslor hos patienter med Synfältsdefekter

Patients suffering from homonymous hemianopia after infarction of the posterior cerebral artery (PCA) report different degrees of constraint in daily ...

Optimized System for Cerebral Perfusion Monitoring in the Rat Stroke Model of Intraluminal Middle Cerebral Artery Occlusion

The translational potential of pre-clinical stroke research depends on the accuracy of experimental modeling. Cerebral perfusion monitoring in animal models of acute ischemic stroke allows to confirm successful arterial occlusion and exclude subarachnoid hemorrhage. Cerebral perfusion monitoring can also be used to study intracranial collateral circulation, which is emerging as a powerful determinant of stroke outcome and a possible therapeutic target. Despite a recognized role of Laser Doppler perfusion monitoring as part of the current guidelines for experimental cerebral ischemia, a number of technical difficulties exist that limit its widespread use. One of the major issues is obtaining a secure and prolonged attachment of a deep-penetration Laser Doppler probe to the animal skull. In this video, we show our optimized system for cerebral perfusion monitoring during transient middle cerebral artery occlusion by intraluminal filament in the rat. We developed in-house a simple method to obtain a custom made holder for twin-fibre (deep-penetration) Laser Doppler probes, which allow multi-site monitoring if needed. A continuous and prolonged monitoring of cerebral perfusion could easily be obtained over the intact skull.

Cerebral perfusion monitoring has been demonstrated to improve accuracy in ischemic stroke models. Technical difficulties often limit the use of this essential tool for cerebrovascular research. In this video, an optimized system is shown to obtain a single or multi-site hemodynamic monitoring during intraluminal middle cerebral artery occlusion in rats.

Optimerat system för cerebral perfusion övervakning i råtta Stroke Modell av Intraluminal Middle cerebral artärocklusion

The translational potential of pre-clinical stroke research depends on the accuracy of experimental modeling. Cerebral perfusion monitoring in animal ...

Permanent Cerebral Vessel Occlusion via Double Ligature and Transection

Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow (ischemia) 1. Middle cerebral artery (MCA) delivers a great majority of blood to the lateral surface of the cortex 2, is the most common site of human stroke 3, and ischemia within its territory can result in extensive dysfunction or death 1,4,5. Survivors of ischemic stroke often suffer loss or disruption of motor capabilities, sensory deficits, and infarct. In an effort to capture these key characteristics of stroke, and thereby develop effective treatment, a great deal of emphasis is placed upon animal models of ischemia in MCA.
Here we present a method of permanently occluding a cortical surface blood vessel. We will present this method using an example of a relevant vessel occlusion that models the most common type, location, and outcome of human stroke, permanent middle cerebral artery occlusion (pMCAO). In this model, we surgically expose MCA in the adult rat and subsequently occlude via double ligature and transection of the vessel. This pMCAO blocks the proximal cortical branch of MCA, causing ischemia in all of MCA cortical territory, a large portion of the cortex. This method of occlusion can also be used to occlude more distal portions of cortical vessels in order to achieve more focal ischemia targeting a smaller region of cortex. The primary disadvantages of pMCAO are that the surgical procedure is somewhat invasive as a small craniotomy is required to access MCA, though this results in minimal tissue damage. The primary advantages of this model, however, are: the site of occlusion is well defined, the degree of blood flow reduction is consistent, functional and neurological impairment occurs rapidly, infarct size is consistent, and the high rate of survival allows for long-term chronic assessment.

Permanent Cerebral Vessel Occlusion via Double Ligature and Transection

We describe a highly reproducible method for the permanent occlusion of a rodent major cerebral blood vessel. This technique can be accomplished with very little peripheral damage, minimal blood loss, a high rate of long-term survival, and consistent infarct volume commensurate with the human clinical population.

Permanent Cerebral kärlocklusion<em&gt; Via</em&gt; Dubbel Ligature och transektion

Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow ...

Generation and 3-Dimensional Quantitation of Arterial Lesions in Mice Using Optical Projection Tomography

The generation and analysis of vascular lesions in appropriate animal models is a cornerstone of research into cardiovascular disease, generating important information on the pathogenesis of lesion formation and the action of novel therapies. Use of atherosclerosis-prone mice, surgical methods of lesion induction, and dietary modification has dramatically improved understanding of the mechanisms that contribute to disease development and the potential of new treatments.
Classically, analysis of lesions is performed ex vivo using 2-dimensional histological techniques. This article describes application of optical projection tomography (OPT) to 3-dimensional quantitation of arterial lesions. As this technique is non-destructive, it can be used as an adjunct to standard histological and immunohistochemical analyses.
Neointimal lesions were induced by wire-insertion or ligation of the mouse femoral artery whilst atherosclerotic lesions were generated by administration of an atherogenic diet to apoE-deficient mice.
Lesions were examined using OPT imaging of autofluorescent emission followed by complementary histological and immunohistochemical analysis. OPT clearly distinguished lesions from the underlying vascular wall. Lesion size was calculated in 2-dimensional sections using planimetry, enabling calculation of lesion volume and maximal cross-sectional area. Data generated using OPT were consistent with measurements obtained using histology, confirming the accuracy of the technique and its potential as a complement (rather than alternative) to traditional methods of analysis.
This work demonstrates the potential of OPT for imaging atherosclerotic and neointimal lesions. It provides a rapid, much needed ex vivo technique for the routine 3-dimensional quantification of vascular remodelling.

Ex vivo analysis of arterial lesions from animal models of cardiovascular disease classically relies on histological and immunohistochemical techniques. These provide 2-dimensional measurements in 3-dimensional lesions. This manuscript describes the generation of arterial lesions for quantitative analysis in 3-dimensions using optical projection tomography.

Generation och 3-dimensionell kvantifiering av arteriell Skador i möss med användning av optisk Projection Tomography

The generation and analysis of vascular lesions in appropriate animal models is a cornerstone of research into cardiovascular disease, generating ...

Quantitative Analysis and Characterization of Atherosclerotic Lesions in the Murine Aortic Sinus

Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have been developed to facilitate the study of the molecular and cellular pathophysiology of this disease. In this manuscript we describe specific techniques for the quantification and characterization of atherosclerotic lesions in the murine aortic sinus and ascending aorta. The advantage of this procedure is that it provides an accurate measurement of the cross-sectional area and total volume of the lesion, which can be used to compare atherosclerotic progression across different treatment groups. This is possible through the use of the valve leaflets as an anatomical landmark, together with careful adjustment of the sectioning angle. We also describe basic staining methods that can be used to begin to characterize atherosclerotic progression. These can be further modified to investigate antigens of specific interest to the researcher. The described techniques are generally applicable to a wide variety of existing and newly created dietary and genetically-induced models of atherogenesis.

We describe procedures to quantify and characterize atherosclerotic lesions in mouse models using precision sectioning of the aortic sinus and ascending aorta combined with histochemical and immunohistochemical analysis.

Kvantitativ Analys och karakterisering av aterosklerotiska lesioner i murina Aorta Sinus

Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have ...

Dynamic Visual Tests to Identify and Quantify Visual Damage and Repair Following Demyelination in Optic Neuritis Patients

In order to follow optic neuritis patients and evaluate the effectiveness of their treatment, a handy, accurate and quantifiable tool is required to assess changes in myelination at the central nervous system (CNS). However, standard measurements, including routine visual tests and MRI scans, are not sensitive enough for this purpose. We present two visual tests addressing dynamic monocular and binocular functions which may closely associate with the extent of myelination along visual pathways. These include Object From Motion (OFM) extraction and Time-constrained stereo protocols. In the OFM test, an array of dots compose an object, by moving the dots within the image rightward while moving the dots outside the image leftward or vice versa. The dot pattern generates a camouflaged object that cannot be detected when the dots are stationary or moving as a whole. Importantly, object recognition is critically dependent on motion perception. In the Time-constrained Stereo protocol, spatially disparate images are presented for a limited length of time, challenging binocular 3-dimensional integration in time. Both tests are appropriate for clinical usage and provide a simple, yet powerful, way to identify and quantify processes of demyelination and remyelination along visual pathways. These protocols may be efficient to diagnose and follow optic neuritis and multiple sclerosis patients.
In the diagnostic process, these protocols may reveal visual deficits that cannot be identified via current standard visual measurements. Moreover, these protocols sensitively identify the basis of the currently unexplained continued visual complaints of patients following recovery of visual acuity. In the longitudinal follow up course, the protocols can be used as a sensitive marker of demyelinating and remyelinating processes along time. These protocols may therefore be used to evaluate the efficacy of current and evolving therapeutic strategies, targeting myelination of the CNS.

Object From Motion (OFM) and Time-constrained stereo protocols are sensitive tools to identify monocular and binocular dynamic visual function deficits, which are uniquely affected in optic neuritis patients. Furthermore, these tests may be used as quantitative noninvasive tools to assess the extent of myelination along visual pathways.

Dynamiska visuella tester för att identifiera och kvantifiera Visual skador och reparera Efter Demyelinisering i optikusneurit patienter

In order to follow optic neuritis patients and evaluate the effectiveness of their treatment, a handy, accurate and quantifiable tool is required to ...

A Versatile Murine Model of Subcortical White Matter Stroke for the Study of Axonal Degeneration and White Matter Neurobiology

Stroke affecting white matter accounts for up to 25% of clinical stroke presentations, occurs silently at rates that may be 5-10 fold greater, and contributes significantly to the development of vascular dementia. Few models of focal white matter stroke exist and this lack of appropriate models has hampered understanding of the neurobiologic mechanisms involved in injury response and repair after this type of stroke. The main limitation of other subcortical stroke models is that they do not focally restrict the infarct to the white matter or have primarily been validated in non-murine species. This limits the ability to apply the wide variety of murine research tools to study the neurobiology of white matter stroke. Here we present a methodology for the reliable production of a focal stroke in murine white matter using a local injection of an irreversible eNOS inhibitor. We also present several variations on the general protocol including two unique stereotactic variations, retrograde neuronal tracing, as well as fresh tissue labeling and dissection that greatly expand the potential applications of this technique. These variations allow for multiple approaches to analyze the neurobiologic effects of this common and understudied form of stroke.

Here we present methodology for the production of a focal stroke in murine white matter by local injection of an irreversible endothelial nitric oxide synthase (eNOS) inhibitor (L-Nio). Presented are two stereotactic variations, retrograde neuronal tracing, and fresh tissue labeling and dissection that expand the potential applications of this technique.

En mångsidig Murina Modell av subkortikala vita substansen Stroke för studien av axonal degeneration och vit substans neurobiologi

Stroke affecting white matter accounts for up to 25% of clinical stroke presentations, occurs silently at rates that may be 5-10 fold greater, and ...

Autologous Microfractured and Purified Adipose Tissue for Arthroscopic Management of Osteochondral Lesions of the Talus

In recent years, regenerative techniques have been increasingly studied and used to treat osteochondral lesions of the talus. In particular, several studies have focused their attention on mesenchymal stem cells derived from adipose tissue. Adipose-derived stem cells (ADSCs) exhibit morphological characteristics and properties similar to other mesenchymal cells, and are able to differentiate into several cellular lines. Moreover, these cells are also widely available in the subcutaneous tissue, representing 10 - 30% of the normal body weight, with a concentration of 5,000 cells per gram of tissue.
In the presented technique, the first step involves harvesting ADSCs from the abdomen and a process of microfracture and purification; next, the surgical procedure is performed entirely arthroscopically, with less soft tissue dissection, better joint visualization, and a faster recovery compared with standard open procedures. Arthroscopy is characterized by a first phase in which the lesion is identified, isolated, and prepared with microperforations; the second step, performed dry, involves injection of adipose tissue at the level of the lesion.
Between January 2016 and September 2016, four patients underwent arthroscopic treatment of osteochondral lesion of the talus with microfractured and purified adipose tissue. All patients reported clinical improvement six months after surgery with no reported complications. Functional scores at the latest follow-up are encouraging and confirm that the technique provides reliable pain relief and improvements in patients with osteochondral lesion of the talus.

The aim of this study is to report a protocol for the arthroscopic treatment of osteochondral lesions of the talus using microfractured and purified adipose-derived stem cells.

Autolog Microfractured och renat fettvävnad för artroskopisk hantering av osteokondrala lesioner av Talus

In recent years, regenerative techniques have been increasingly studied and used to treat osteochondral lesions of the talus. In particular, several ...

Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm

Vestibular disorders are among the most common syndromes in medicine. In recent years, new vestibular diagnostic systems have been introduced that allow the examination of all semicircular canals in the clinical setting. Assessment methods of the otolithic system, which is responsible for the perception of linear acceleration and perception of gravity, are far less in clinical use. There are several experimental approaches for measuring the perception of gravity. The most frequently used method is the determination of the subjective visual vertical. This is usually measured with the head in an upright position. We present here an assessment method for testing otolith function in the roll plane. The subjective visual vertical is measured in the head upright position as well as with head inclination of &#177; 15&#176; and &#177; 30&#176; in the roll plane. This extended functional paradigm is an easy-to-perform clinical test of otolith function and ensures increased information content for the detection of impaired graviceptive perception.

The perception of gravity is commonly determined by the subjective visual vertical in the head upright position. The additional assessment at head tilts of &#177; 15&#176; and &#177; 30&#176; in the roll plane ensures increased information content for the detection of impaired graviceptive perception.

Bedömning av statisk graviceptiv perception i roll-planet med hjälp av subjektiva Visuella vertikala paradigm

Vestibular disorders are among the most common syndromes in medicine. In recent years, new vestibular diagnostic systems have been introduced that allow ...