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380 results on '"Larsson, E.-M."'

20. Quantitative MRI using relaxometry in malignant gliomas detects contrast enhancement in peritumoral oedema

Author

Blystad, I, Warntjes, J. B. M., Smedby, Örjan, Lundberg, P., Larsson, E-M, Tisell, A., Blystad, I, Warntjes, J. B. M., Smedby, Örjan, Lundberg, P., Larsson, E-M, and Tisell, A.

Abstract

Malignant gliomas are primary brain tumours with an infiltrative growth pattern, often with contrast enhancement on magnetic resonance imaging (MRI). However, it is well known that tumour infiltration extends beyond the visible contrast enhancement. The aim of this study was to investigate if there is contrast enhancement not detected visually in the peritumoral oedema of malignant gliomas by using relaxometry with synthetic MRI. 25 patients who had brain tumours with a radiological appearance of malignant glioma were prospectively included. A quantitative MR-sequence measuring longitudinal relaxation (R-1), transverse relaxation (R-2) and proton density (PD), was added to the standard MRI protocol before surgery. Five patients were excluded, and in 20 patients, synthetic MR images were created from the quantitative scans. Manual regions of interest (ROIs) outlined the visibly contrast-enhancing border of the tumours and the peritumoral area. Contrast enhancement was quantified by subtraction of native images from post GD-images, creating an R-1-difference-map. The quantitative R-1-difference-maps showed significant contrast enhancement in the peritumoral area (0.047) compared to normal appearing white matter (0.032), p = 0.048. Relaxometry detects contrast enhancement in the peritumoral area of malignant gliomas. This could represent infiltrative tumour growth., QC 20210304

Published
2020
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32. Preserved white matter microstructure in adolescent patients with atypical anorexia nervosa

Author

Olivo, G, Swenne, I, Zhukovsky, C, Tuunainen, A-K, Saaid, A, Salonen-Ros, H, Larsson, E-M, Brooks, SJ, and Schiöth, HB

Subjects
Psychiatry, cognitive neuroscience, neuroimaging, adolescent, brain, RC0321, BF, diffusion tensor imaging, feeding and eating disorders, anorexia nervosa, Psykiatri
Abstract

Objective: Patients with atypical anorexia nervosa (AN) are often in the normal-weight range at presentation; however, signs of starvation and medical instability are not rare. White matter (WM) microstructural correlates of atypical AN have not yet been investigated, leaving an important gap in our knowledge regarding the neural pathogenesis of this disorder.\ud Method: We investigated WM microstructural integrity in 25 drug-naïve adolescent patients with atypical AN and 25 healthy controls, using diffusion tensor imaging (DTI) with a tract-based spatial statistics (TBSS) approach. Psychological variables related to the eating disorder and depressive symptoms were also evaluated by administering the eating disorder examination questionnaire (EDE-Q) and the Montgomery–Åsberg depression rating scale (MADRS-S) respectively, to all participants.\ud Results: Patients and controls were in the normal-weight range and did not differ from the body mass index standard deviations for their age. No between groups difference in WM microstructure could be detected.\ud Discussion: Our findings support the hypothesis that brain structural alterations may not be associated to early-stage atypical AN. These findings also suggest that previous observations of alterations in WM microstructure in full syndrome AN may constitute state-related consequences of severe weight loss. Whether the preservation of WM structure is a pathogenetically discriminant feature of atypical AN or only an effect of a less severe nutritional disturbance, will have to be verified by future studies on larger samples, possibly directly comparing AN and atypical AN.

Published
2019

35. Aqueductal CSF Stroke Volume Is Increased in Patients with Idiopathic Normal Pressure Hydrocephalus and Decreases after Shunt Surgery

Author

Shanks, J., Bloch, K. Markenroth, Laurell, Katarina, Cesarini, K. G., Fahlstroem, M., Larsson, E-M, Virhammar, J., Shanks, J., Bloch, K. Markenroth, Laurell, Katarina, Cesarini, K. G., Fahlstroem, M., Larsson, E-M, and Virhammar, J.

Abstract

BACKGROUND AND PURPOSE: Increased CSF stroke volume through the cerebral aqueduct has been proposed as a possible indicator of positive surgical outcome in patients with idiopathic normal pressure hydrocephalus; however, consensus is lacking. In this prospective study, we aimed to compare CSF flow parameters in patients with idiopathic normal pressure hydrocephalus with those in healthy controls and change after shunt surgery and to investigate whether any parameter could predict surgical outcome. MATERIALS AND METHODS: Twenty-one patients with idiopathic normal pressure hydrocephalus and 21 age- and sex-matched healthy controls were prospectively included and examined clinically and with MR imaging of the brain. Eighteen patients were treated with shunt implantation and were re-examined clinically and with MR imaging the day before the operation and 3 months postoperatively. All MR imaging scans included a phase-contrast sequence. RESULTS: The median aqueductal CSF stroke volume was significantly larger in patients compared with healthy controls (103.5 μL; interquartile range, 69.8–142.8 μL) compared with 62.5 μL (interquartile range, 58.3–73.8 μL; P < .01) and was significantly reduced 3 months after shunt surgery from 94.8 μL (interquartile range, 81–241 μL) to 88 μL (interquartile range, 51.8–173.3 μL; P < .05). Net flow in the caudocranial direction (retrograde) was present in 11/21 patients and in 10/21 controls. Peak flow and net flow did not differ between patients and controls. There were no correlations between any CSF flow parameters and surgical outcomes. CONCLUSIONS: Aqueductal CSF stroke volume was increased in patients with idiopathic normal pressure hydrocephalus and decreased after shunt surgery, whereas retrograde aqueductal net flow did not seem to be specific for patients with idiopathic normal pressure hydrocephalus. On the basis of the results, the usefulness of CSF flow parameters to predict outcome after shunt surgery seem to be limited

Published
2019
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39. The idiopathic normal-pressure hydrocephalus Radscale : a radiological scale for structured evaluation

Author

Kockum, Karin, Lilja-Lund, Otto, Larsson, E. -M, Rosell, M., Söderström, L., Virhammar, J., Laurell, Katarina, Kockum, Karin, Lilja-Lund, Otto, Larsson, E. -M, Rosell, M., Söderström, L., Virhammar, J., and Laurell, Katarina

Abstract

Background and purpose: Despite the important role of imaging in diagnosing idiopathic normal‐pressure hydrocephalus (iNPH), a structured overall assessment of radiological signs is still lacking. The purpose of this study was to construct a radiological scale, composed of morphological signs of iNPH, and compare it with clinical symptoms. Methods: In this prospective, population‐based study of iNPH, 168 individuals (93 females) [mean age 75 (range 66–92) years] underwent computed tomography of the brain and a neurological examination with assessment of clinical symptoms according to Hellström's iNPH scale. Two radiologists, blinded to clinical data, independently evaluated and measured eight radiological parameters, i.e. Evans’ index, callosal angle, size of temporal horns, narrow high‐convexity sulci, dilated Sylvian fissures, focally dilated sulci, peri‐ventricular hypodensities and bulging of the lateral ventricular roof. Results: In a linear regression model, all parameters except ventricular roof bulging were significantly associated with clinical iNPH symptoms. The seven remaining parameters were summarized into a total iNPH Radscale score ranging from 0 to 12. There was a significant correlation (r = 0.55, P < 0.001) between the total iNPH Radscale score and clinical symptoms. The inter‐rater agreement for the included radiological parameters was high (intraclass correlation, 0.74–0.97). Conclusion: The iNPH Radscale may become a valuable diagnostic screening tool, allowing a structured radiological assessment. A high iNPH Radscale score together with clinical symptoms should raise suspicion of iNPH, motivating further evaluation for shunt surgery.

Published
2018
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40. Diffusion tensor imaging and tractography of the white matter in normal aging : The rate-of-change differs between segments within tracts.

Author

Mårtensson, J, Lätt, J, Åhs, Fredrik, Fredrikson, M, Söderlund, H, Schiöth, H B, Kok, J, Kremer, B, van Westen, Danielle, Larsson, E-M, Nilsson, M, Mårtensson, J, Lätt, J, Åhs, Fredrik, Fredrikson, M, Söderlund, H, Schiöth, H B, Kok, J, Kremer, B, van Westen, Danielle, Larsson, E-M, and Nilsson, M

Abstract

Knowledge concerning the normal aging of cerebral white matter will improve our understanding of abnormal changes in neurodegenerative diseases. The microstructural basis of white matter maturation and aging can be investigated using diffusion tensor imaging (DTI). Generally, diffusion anisotropy increases during childhood and adolescence followed by a decline in middle age. However, this process is subject to spatial variations between tracts. The aim of this study was to investigate to what extent age-related variations also occur within tracts. DTI parameters were compared between segments of two white matter tracts, the cingulate bundle (CB) and the inferior fronto-occipital fasciculus (IFO), in 257 healthy individuals between 13 and 84years of age. Segments of the CB and the IFO were extracted and parameters for each segment were averaged across the hemispheres. The data was analysed as a function of age. Results show that age-related changes differ both between and within individual tracts. Different age trajectories were observed in all segments of the analysed tracts for all DTI parameters. In conclusion, aging does not affect white matter tracts uniformly but is regionally specific; both between and within white matter tracts.

Published
2018
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41. Synthesizing a Contrast-Enhancement Map in Patients with High-Grade Gliomas Based on a Postcontrast MR Imaging Quantification Only

Author

Warntjes, Marcel Jan Bertus, Blystad, Ida, Tisell, Anders, Larsson, E. -M., Warntjes, Marcel Jan Bertus, Blystad, Ida, Tisell, Anders, and Larsson, E. -M.

Abstract

BACKGROUND AND PURPOSE: Administration of a gadolinium-based contrast agent is an important diagnostic biomarker for blood-brain barrier damage. In clinical use, detection is based on subjective comparison of native and postgadolinium-based contrast agent T1-weighted images. Quantitative MR imaging studies have suggested a relation between the longitudinal relaxation rate and proton-density in the brain parenchyma, which is disturbed by gadolinium-based contrast agents. This discrepancy can be used to synthesize a contrast-enhancement map based solely on the postgadolinium-based contrast agent acquisition. The aim of this study was to compare synthetic enhancement maps with subtraction maps of native and postgadolinium-based contrast agent images. MATERIALS AND METHODS: For 14 patients with high-grade gliomas, quantitative MR imaging was performed before and after gadolinium-based contrast agent administration. The quantification sequence was multidynamic and multiecho, with a scan time of 6 minutes. The 2 image stacks were coregistered using in-plane transformation. The longitudinal relaxation maps were subtracted and correlated with the synthetic longitudinal relaxation enhancement maps on the basis of the postgadolinium-based contrast agent images only. ROIs were drawn for tumor delineation. RESULTS: Linear regression of the subtraction and synthetic longitudinal relaxation enhancement maps showed a slope of 1.02 0.19 and an intercept of 0.05 +/- 0.12. The Pearson correlation coefficient was 0.861 +/- 0.059, and the coefficient of variation was 0.18 +/- 0.04. On average, a volume of 1.71 +/- 1.28 mL of low-intensity enhancement was detected in the synthetic enhancement maps outside the borders of the drawn ROI. CONCLUSIONS: The study shows that there was a good correlation between subtraction longitudinal relaxation enhancement maps and synthetic longitudinal relaxation enhancement maps in patients with high-grade gliomas. The method may improve the sensitivity a

Published
2018
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49. Abstracts from Hydrocephalus 2016

Author

Adam, A., primary, Robison, J., additional, Lu, J., additional, Jose, R., additional, Badran, N., additional, Vivas-Buitrago, T., additional, Rigamonti, D., additional, Sattar, A., additional, Omoush, O., additional, Hammad, M., additional, Dawood, M., additional, Maghaslah, M., additional, Belcher, T., additional, Carson, K., additional, Hoffberger, J., additional, Jusué Torres, I., additional, Foley, S., additional, Yasar, S., additional, Thai, Q. A., additional, Wemmer, J., additional, Klinge, P., additional, Al-Mutawa, L., additional, Al-Ghamdi, H., additional, Carson, K. A., additional, Asgari, M., additional, de Zélicourt, D., additional, Kurtcuoglu, V., additional, Garnotel, S., additional, Salmon, S., additional, Balédent, O., additional, Lokossou, A., additional, Page, G., additional, Balardy, L., additional, Czosnyka, Z., additional, Payoux, P., additional, Schmidt, E. A., additional, Zitoun, M., additional, Sevestre, M. A., additional, Alperin, N., additional, Baudracco, I., additional, Craven, C., additional, Matloob, S., additional, Thompson, S., additional, Haylock Vize, P., additional, Thorne, L., additional, Watkins, L. D., additional, Toma, A. K., additional, Bechter, Karl, additional, Pong, A. C., additional, Jugé, L., additional, Bilston, L. E., additional, Cheng, S., additional, Bradley, W., additional, Hakim, F., additional, Ramón, J. F., additional, Cárdenas, M. F., additional, Davidson, J. S., additional, García, C., additional, González, D., additional, Bermúdez, S., additional, Useche, N., additional, Mejía, J. A., additional, Mayorga, P., additional, Cruz, F., additional, Martinez, C., additional, Matiz, M. C., additional, Vallejo, M., additional, Ghotme, K., additional, Soto, H. A., additional, Riveros, D., additional, Buitrago, A., additional, Mora, M., additional, Murcia, L., additional, Bermudez, S., additional, Cohen, D., additional, Dasgupta, D., additional, Curtis, C., additional, Domínguez, L., additional, Remolina, A. J., additional, Grijalba, M. A., additional, Whitehouse, K. J., additional, Edwards, R. J., additional, Eleftheriou, A., additional, Lundin, F., additional, Fountas, K. N., additional, Kapsalaki, E. Z., additional, Smisson, H. F., additional, Robinson, J. S., additional, Fritsch, M. J., additional, Arouk, W., additional, Garzon, M., additional, Kang, M., additional, Sandhu, K., additional, Baghawatti, D., additional, Aquilina, K., additional, James, G., additional, Thompson, D., additional, Gehlen, M., additional, Schmid Daners, M., additional, Eklund, A., additional, Malm, J., additional, Gomez, D., additional, Guerra, M., additional, Jara, M., additional, Flores, M., additional, Vío, K., additional, Moreno, I., additional, Rodríguez, S., additional, Ortega, E., additional, Rodríguez, E. M., additional, McAllister, J. P., additional, Guerra, M. M., additional, Morales, D. M., additional, Sival, D., additional, Jimenez, A., additional, Limbrick, D. D., additional, Ishikawa, M., additional, Yamada, S., additional, Yamamoto, K., additional, Junkkari, A., additional, Häyrinen, A., additional, Rauramaa, T., additional, Sintonen, H., additional, Nerg, O., additional, Koivisto, A. M., additional, Roine, R. P., additional, Viinamäki, H., additional, Soininen, H., additional, Luikku, A., additional, Jääskeläinen, J. E., additional, Leinonen, V., additional, Kehler, U., additional, Lilja-Lund, O., additional, Kockum, K., additional, Larsson, E. M., additional, Riklund, K., additional, Söderström, L., additional, Hellström, P., additional, Laurell, K., additional, Kojoukhova, M., additional, Sutela, A., additional, Vanninen, R., additional, Vanha, K. I., additional, Timonen, M., additional, Rummukainen, J., additional, Korhonen, V., additional, Helisalmi, S., additional, Solje, E., additional, Remes, A. M., additional, Huovinen, J., additional, Paananen, J., additional, Hiltunen, M., additional, Kurki, M., additional, Martin, B., additional, Loth, F., additional, Luciano, M., additional, Luikku, A. J., additional, Hall, A., additional, Herukka, S. K., additional, Mattila, J., additional, Lötjönen, J., additional, Alafuzoff, I., additional, Jurjević, I., additional, Miyajima, M., additional, Nakajima, M., additional, Murai, H., additional, Shin, T., additional, Kawaguchi, D., additional, Akiba, C., additional, Ogino, I., additional, Karagiozov, K., additional, Arai, H, additional, Reis, R. C., additional, Teixeira, M. J., additional, Valêncio, C. G., additional, da Vigua, D., additional, Almeida-Lopes, L., additional, Mancini, M. W., additional, Pinto, F. C. G., additional, Maykot, R. H., additional, Calia, G., additional, Tornai, J., additional, Silvestre, S. S. S., additional, Mendes, G., additional, Sousa, V., additional, Bezerra, B., additional, Dutra, P., additional, Modesto, P., additional, Oliveira, M. F., additional, Petitto, C. E., additional, Pulhorn, H., additional, Chandran, A., additional, McMahon, C., additional, Rao, A. S., additional, Jumaly, M., additional, Solomon, D., additional, Moghekar, A., additional, Relkin, N., additional, Hamilton, M., additional, Katzen, H., additional, Williams, M., additional, Bach, T., additional, Zuspan, S., additional, Holubkov, R., additional, Rigamonti, A., additional, Clemens, G., additional, Sharkey, P., additional, Sanyal, A., additional, Sankey, E., additional, Rigamonti, K., additional, Naqvi, S., additional, Hung, A., additional, Schmidt, E., additional, Ory-Magne, F., additional, Gantet, P., additional, Guenego, A., additional, Januel, A. C., additional, Tall, P., additional, Fabre, N., additional, Mahieu, L., additional, Cognard, C., additional, Gray, L., additional, Buttner-Ennever, J. A., additional, Takagi, K., additional, Onouchi, K, additional, Thompson, S. D., additional, Thorne, L. D., additional, Tully, H. M., additional, Wenger, T. L., additional, Kukull, W. A., additional, Doherty, D., additional, Dobyns, W. B., additional, Moran, D., additional, Vakili, S., additional, Patel, M. A., additional, Elder, B., additional, Goodwin, C. R., additional, Crawford, J. A., additional, Pletnikov, M. V., additional, Xu, J., additional, Blitz, A., additional, Herzka, D. A., additional, Guerrero-Cazares, H., additional, Quiñones-Hinojosa, A., additional, Mori, S., additional, Saavedra, P., additional, Treviño, H., additional, Maitani, K., additional, Ziai, W. C., additional, Eslami, V., additional, Nekoovaght-Tak, S., additional, Dlugash, R., additional, Yenokyan, G., additional, McBee, N., additional, and Hanley, D. F., additional

Published
2017
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