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Schneider F, Wolpert F, Stolzmann P, Albatly AA, Kenkel D, Weller J, Weller M, Kollias SS, Rushing EJ, Veit-Haibach P, Huellner MW. Prognostic value of O-(2-[ 18F]-fluoroethyl)-L-tyrosine PET in relapsing oligodendroglioma. Acta Oncol 2020; 59:1357-1364. [PMID: 32686979 DOI: 10.1080/0284186x.2020.1787507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To assess the relationship between F-18-fluoro-ethyl-tyrosine positron emission tomography (FET-PET) parameters of relapsing oligodendroglioma and progression-free survival. MATERIAL AND METHODS The relationship of clinical parameters, FET-PET parameters (SUVmax, TBRmax, BTV, time-activity curves) and progression-free survival was analyzed using univariate and multivariate analysis in 42 adult patients with relapsing oligodendroglioma. Kaplan-Meier analysis was used to assess survival. RESULTS Patients who did not undergo surgical resection of their relapsing tumor had significantly lower PFS if the tumor exhibited an SUVmax above 3.40 than those with an SUVmax below 3.40 (13.1 ± 2.3 months vs. 47.3 ± 6.0 months, respectively, p < .001). Patients who underwent surgery had similar PFS as the aforementioned non-operated patients with low SUVmax (53.6 ± 6.7 months, p = .948). The same was true for TBRmax using a threshold of 3.03 (PFS 12.5 ± 2.4 months vs. 44.0 ± 6.3 months / 53.6 ± 6.7 months, respectively; p < .001 / p = .825). Also, subjects with BTV below 10 cm3 that did not undergo surgery had a similar PFS as subjects who underwent surgery (40.2 ± 6.0 months vs. 52.4 ± 8.9 months, respectively, p = .587). Subjects with BTV above 10 cm3 and without surgery had a significantly worse PFS (13.8 ± 3.3 months, p < .001). Multivariate analysis showed that the prognostication by clinical parameters is improved by adding TBRmax to the model (AUC 0.945 (95% CI: 0.881-1.000), true classification rate 88.1%). CONCLUSION FET-PET may provide added value for the prognostication of relapsing oligodendroglioma in addition to clinical parameters.
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Affiliation(s)
- Florian Schneider
- Department of Nuclear Medicine, University Hospital Zurich/University of Zurich, Zürich, Switzerland
| | - Fabian Wolpert
- Department of Neurology, University Hospital Zurich/University of Zurich, Zurich, Switzerland
| | - Paul Stolzmann
- Department of Nuclear Medicine, University Hospital Zurich/University of Zurich, Zürich, Switzerland
| | - Abdulrahman A. Albatly
- Department of Nuclear Medicine, University Hospital Zurich/University of Zurich, Zürich, Switzerland
| | - David Kenkel
- Department of Nuclear Medicine, University Hospital Zurich/University of Zurich, Zürich, Switzerland
| | - Jonathan Weller
- Department of Nuclear Medicine, University Hospital Zurich/University of Zurich, Zürich, Switzerland
| | - Michael Weller
- Department of Neurology, University Hospital Zurich/University of Zurich, Zurich, Switzerland
| | - Spyros S. Kollias
- Department of Neuroradiology, University Hospital Zurich/University of Zurich, Zürich, Switzerland
| | - Elisabeth J. Rushing
- Department of Neuropathology, University Hospital Zurich/University of Zurich, Zurich, Switzerland
| | - Patrick Veit-Haibach
- Department of Nuclear Medicine, University Hospital Zurich/University of Zurich, Zürich, Switzerland
| | - Martin W. Huellner
- Department of Nuclear Medicine, University Hospital Zurich/University of Zurich, Zürich, Switzerland
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Péus D, Kollias SS, Huber AM, Huber GF. Recurrent unilateral peripheral facial palsy in a patient with an enlarged styloid process. Head Neck 2018; 41:E34-E37. [DOI: 10.1002/hed.25384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 02/22/2018] [Accepted: 05/31/2018] [Indexed: 12/28/2022] Open
Affiliation(s)
- Dominik Péus
- Department of Otorhinolaryngology, Head and Neck Surgery; University of Zurich; Zurich Switzerland
- Department of Otorhinolaryngology, Head and Neck Surgery; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - Spyros S. Kollias
- Institute of Neuro-Radiology; University of Zurich; Zurich Switzerland
| | - Alexander M. Huber
- Department of Otorhinolaryngology, Head and Neck Surgery; University of Zurich; Zurich Switzerland
| | - Gerhard F. Huber
- Department of Otorhinolaryngology, Head and Neck Surgery; University of Zurich; Zurich Switzerland
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3
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Barbagallo M, Albatly AA, Schreiner S, Hayward-Könnecke HK, Buck A, Kollias SS, Huellner MW. Value of 18F-FET PET in Patients With Suspected Tumefactive Demyelinating Disease-Preliminary Experience From a Retrospective Analysis. Clin Nucl Med 2018; 43:e385-e391. [PMID: 30153143 DOI: 10.1097/rlu.0000000000002244] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PURPOSE To investigate the diagnostic value of F-fluoroethyl-L-tyrosine (FET) positron emission tomography (PET) in patients with suspected tumefactive demyelinating disease. METHODS We retrospectively examined FET-PET and MR imaging of 21 patients (12 female, 9 male) with known demyelinating disease and newly diagnosed tumefactive lesions. The maximum standardized uptake value (SUVmax), time activity curves (TAC) and lesion-to-background ratio (TBR) of these lesions were calculated. The standard of reference consisted of biopsy and/or follow-up imaging. FET parameters of true neoplastic lesions and tumefactive demyelinating lesions were compared using Mann-Whitney U-test and receiver operating characteristic (ROC) analysis. RESULTS Nine patients (42.9%) had neoplastic lesions, 12 patients (57.1%) had tumefactive demyelinating lesions. TBRmax, SUVmax and TAC were significantly different between demyelinating lesions and neoplastic lesions: Tumors had a higher TBRmax (3.53 ± 1.09 vs. 1.48 ± 0.31, respectively; P < 0.001) and SUVmax (3.95 ± 1.59 vs. 1.86 ± 0.50, respectively; P < 0.001) than tumefactive demyelinating lesions. The TAC of tumors was significantly higher compared to tumefactive demyelinating lesions at all time points (P < 0.05). ROC analysis revealed that a TBRmax threshold of 2.2 and a SUVmax threshold of 2.5 could reliably differentiate tumor and tumefactive demyelination (area under the curve, 1.000 and 0.958, respectively). CONCLUSION In patients with demyelinating disease, FET-PET parameters TBRmax (cut-off 2.2) and SUVmax (cut-off 2.5) are able to distinguish tumefactive demyelinations from true neoplastic lesions.
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Affiliation(s)
| | | | - Simon Schreiner
- Neurology Clinic, University Hospital Zurich/University of Zurich, Frauenklinikstrasse
| | | | | | - Spyros S Kollias
- Department of Neuroradiology, University Hospital Zurich/University of Zurich, Rämistrasse, Zürich, Switzerland
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4
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Albatly AA, Alsamarah AT, Alhawas A, Veit-Haibach P, Buck A, Stolzmann P, Burger IA, Kollias SS, Huellner MW. Value of 18F-FET PET in adult brainstem glioma. Clin Imaging 2018; 51:68-75. [DOI: 10.1016/j.clinimag.2018.01.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 01/25/2018] [Accepted: 01/29/2018] [Indexed: 12/17/2022]
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5
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Sekine T, Barbosa FDG, Delso G, Burger IA, Stolzmann P, Ter Voert EE, Huber GF, Kollias SS, von Schulthess GK, Veit-Haibach P, Huellner MW. Local resectability assessment of head and neck cancer: Positron emission tomography/MRI versus positron emission tomography/CT. Head Neck 2017; 39:1550-1558. [PMID: 28500749 DOI: 10.1002/hed.24783] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/28/2016] [Accepted: 02/08/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The purpose of this study was to compare the diagnostic accuracy of positron emission tomography (PET)/MRI with PET/CT for local resectability of head and neck cancer. METHODS Sequential contrast-enhanced PET/CT-MRI was performed in 58 patients referred for the staging or restaging of head and neck cancer. Tumors were assessed with PET/CT and PET/MRI for the presence of resectability-defining factors: T4b status (mediastinal invasion, invasion of the prevertebral space, and vascular encasement), and another 8 findings that would imply obstacles for surgical cure (invasion of the laryngeal cartilage, invasion of the preepiglottic fat pad, perineural spread, orbital invasion, bone infiltration, skull base invasion, dural infiltration, and invasion of the brachial plexus). RESULTS The sensitivity/specificity/accuracy of local resectability-defining factors of PET/CT and PET/MRI was 0.92/0.99/0.98 and 0.98/0.99/0.99 (P = .727), respectively, per lesion, and 0.96/0.87/0.91 and 0.96/0.90/0.93 (P = .687), respectively, per patient. CONCLUSION Both contrast-enhanced PET/MRI and contrast-enhanced PET/CT can serve as reliable examinations for defining local resectability of head and neck cancer.
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Affiliation(s)
- Tetsuro Sekine
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland.,Department of Radiology, Nippon Medical School, Tokyo, Japan
| | - Felipe de Galiza Barbosa
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Gaspar Delso
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland.,GE Healthcare, Waukesha, Wisconsin
| | - Irene A Burger
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Paul Stolzmann
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Edwin E Ter Voert
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Gerhard F Huber
- Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Spyros S Kollias
- Clinic of Neuroradiology, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Gustav K von Schulthess
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Patrick Veit-Haibach
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland.,Institute of Diagnostic and Interventional Radiology, University Hospital Zurich / University of Zurich, Zurich, Switzerland
| | - Martin W Huellner
- Department of Nuclear Medicine, University Hospital Zurich / University of Zurich, Zurich, Switzerland
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6
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Sekine T, de Galiza Barbosa F, Kuhn FP, Burger IA, Stolzmann P, Huber GF, Kollias SS, von Schulthess GK, Veit-Haibach P, Huellner MW. PET+MR versus PET/CT in the initial staging of head and neck cancer, using a trimodality PET/CT+MR system. Clin Imaging 2017; 42:232-239. [PMID: 28129606 DOI: 10.1016/j.clinimag.2017.01.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/19/2016] [Accepted: 01/10/2017] [Indexed: 11/26/2022]
Abstract
PURPOSE To compare the diagnostic accuracy of PET+MR with PET/CT in the initial staging of head and neck cancer. MATERIALS AND METHODS Contrast-enhanced PET/CT+MR was performed in 27 patients with newly diagnosed head and neck cancer. PET/CT and PET+MR were evaluated separately, and the TNM stage and factors influencing treatment were assessed. RESULTS The TNM staging by PET+MR was comparable to PET/CT (T: p=0.331, N: p=0.453, M: p=0.034). The sensitivity/specificity/accuracy of treatment-influencing factors by PET/CT and PET+MR were 0.68/0.99/0.97, and 1.00/1.00/0.99, respectively. CONCLUSIONS Whole-body staging with PET+MR yields at least equal diagnostic accuracy as PET/CT in head and neck cancer.
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Affiliation(s)
- Tetsuro Sekine
- Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Switzerland; Department of Radiology, Nippon Medical School, Tokyo, Japan.
| | | | - Felix P Kuhn
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland; Clinic of Neuroradiology, University Hospital Zurich, University of Zurich, Switzerland
| | - Irene A Burger
- Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Switzerland
| | - Paul Stolzmann
- Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Switzerland; Clinic of Neuroradiology, University Hospital Zurich, University of Zurich, Switzerland
| | - Gerhard F Huber
- Department of Otorhinolaryngology, University Hospital Zurich, University of Zurich, Switzerland
| | - Spyros S Kollias
- Clinic of Neuroradiology, University Hospital Zurich, University of Zurich, Switzerland
| | - Gustav K von Schulthess
- Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Switzerland
| | - Patrick Veit-Haibach
- Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Switzerland; Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland
| | - Martin W Huellner
- Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Switzerland
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7
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Leitner L, Walter M, Jarrahi B, Wanek J, Diefenbacher J, Michels L, Liechti MD, Kollias SS, Kessler TM, Mehnert U. A novel infusion-drainage device to assess lower urinary tract function in neuro-imaging. BJU Int 2016; 119:305-316. [PMID: 27617867 DOI: 10.1111/bju.13655] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To evaluate the applicability and precision of a novel infusion-drainage device (IDD) for standardized filling paradigms in neuro-urology and functional magnetic resonance imaging (fMRI) studies of lower urinary tract (LUT) function/dysfunction. SUBJECTS/PATIENTS AND METHODS The IDD is based on electrohydrostatic actuation which was previously proven feasible in a prototype setup. The current design includes hydraulic cylinders and a motorized slider to provide force and motion. Methodological aspects have been assessed in a technical application laboratory as well as in healthy subjects (n=33) and patients with LUT dysfunction (n=3) undergoing fMRI during bladder stimulation. After catheterization, the bladder was pre-filled until a persistent desire to void was reported by each subject. The scan paradigm comprised automated, repetitive bladder filling and withdrawal of 100 mL body warm (37 °C) saline, interleaved with rest and sensation rating. Neuroimaging data were analysed using Statistical Parametric Mapping version 12 (SMP12). RESULTS Volume delivery accuracy was between 99.1±1.2% and 99.9±0.2%, for different flow rates and volumes. Magnetic resonance (MR) compatibility was demonstrated by a small decrease in signal-to-noise ratio (SNR), i.e. 1.13% for anatomical and 0.54% for functional scans, and a decrease of 1.76% for time-variant SNR. Automated, repetitive bladder-filling elicited robust (P = 0.05, family-wise error corrected) brain activity in areas previously reported to be involved in supraspinal LUT control. There was a high synchronism between the LUT stimulation and the blood oxygenation level-dependent (BOLD) signal changes in such areas. CONCLUSION We were able to develop an MR-compatible and MR-synchronized IDD to routinely stimulate the LUT during fMRI in a standardized manner. The device provides LUT stimulation at high system accuracy resulting in significant supraspinal BOLD signal changes in interoceptive and LUT control areas in synchronicity to the applied stimuli. The IDD is commercially available, portable and multi-configurable. Such a device may help to improve precision and standardization of LUT tasks in neuro-imaging studies on supraspinal LUT control, and may therefore facilitate multi-site studies and comparability between different LUT investigations in the future.
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Affiliation(s)
- Lorenz Leitner
- Neuro-Urology, Spinal Cord Injury Centre & Research, University of Zürich, Balgrist University Hospital, Zürich, Switzerland.,Department of Urology, University Hospital Basel, Basel, Switzerland
| | - Matthias Walter
- Neuro-Urology, Spinal Cord Injury Centre & Research, University of Zürich, Balgrist University Hospital, Zürich, Switzerland
| | - Behnaz Jarrahi
- Department of Neuroradiology, University Hospital Zürich, Zürich, Switzerland.,UCLA Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, Los Angeles, CA, USA
| | - Johann Wanek
- Neuro-Urology, Spinal Cord Injury Centre & Research, University of Zürich, Balgrist University Hospital, Zürich, Switzerland
| | | | - Lars Michels
- Department of Neuroradiology, University Hospital Zürich, Zürich, Switzerland
| | - Martina D Liechti
- Department of Brain Repair and Rehabilitation, Institute of Neurology, University College London, London, UK
| | - Spyros S Kollias
- Department of Neuroradiology, University Hospital Zürich, Zürich, Switzerland
| | - Thomas M Kessler
- Neuro-Urology, Spinal Cord Injury Centre & Research, University of Zürich, Balgrist University Hospital, Zürich, Switzerland
| | - Ulrich Mehnert
- Neuro-Urology, Spinal Cord Injury Centre & Research, University of Zürich, Balgrist University Hospital, Zürich, Switzerland
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Purohit B, Ganewatte E, Kollias SS. Natalizumab-Related Progressive Multifocal Leukoencephalopathy-Immune Reconstitution Inflammatory Syndrome: A Case Report Highlighting Clinical and MRI Features. Malays J Med Sci 2016; 23:91-95. [PMID: 27904430 DOI: 10.21315/mjms2016.23.5.12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 12/05/2015] [Indexed: 01/06/2023] Open
Abstract
Multiple sclerosis (MS) patients treated with natalizumab often face the uncommon but severe complication of developing progressive multifocal leukoencephalopathy (PML). PML may be further complicated by immune reconstitution inflammatory syndrome (IRIS) after the removal of the drug. Since both PML and IRIS are associated with high morbidity and mortality rates, early clinical and radiological diagnosis of these complications is of paramount importance. Here, we report a case of an adult male patient who was diagnosed with PML after receiving natalizumab therapy for 6 years for the treatment of MS. Upon cessation of natalizumab, he presented with a paradoxical worsening of clinical and radiological findings consistent with an inflammatory brain injury due to IRIS. He was treated with high dose corticosteroid therapy followed by a gradual improvement in clinical and imaging findings. This article illustrates the magnetic resonance imaging (MRI) features of natalizumab-associated PML-IRIS, along with a brief overview of its clinical features, complications and management strategies.
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Affiliation(s)
- Bela Purohit
- Institute for Neuroradiology, University Hospital of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland; Dept. of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore-308433
| | - Eranga Ganewatte
- Institute for Neuroradiology, University Hospital of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
| | - Spyros S Kollias
- Institute for Neuroradiology, University Hospital of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
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9
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Jarrahi B, Gassert R, Wanek J, Michels L, Mehnert U, Kollias SS. Design and Application of a New Automated Fluidic Visceral Stimulation Device for Human fMRI Studies of Interoception. IEEE J Transl Eng Health Med 2016; 4:2000108. [PMID: 27551646 PMCID: PMC4991687 DOI: 10.1109/jtehm.2016.2538239] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Revised: 01/07/2016] [Accepted: 02/29/2016] [Indexed: 02/05/2023]
Abstract
Mapping the brain centers that mediate the sensory-perceptual processing of visceral afferent signals arising from the body (i.e., interoception) is useful both for characterizing normal brain activity and for understanding clinical disorders related to abnormal processing of visceral sensation. Here, we report a novel closed-system, electrohydrostatically driven master–slave device that was designed and constructed for delivering controlled fluidic stimulations of visceral organs and inner cavities of the human body within the confines of a 3T magnetic resonance imaging (MRI) scanner. The design concept and performance of the device in the MRI environment are described. In addition, the device was applied during a functional MRI (fMRI) investigation of visceral stimulation related to detrusor distention in two representative subjects to verify its feasibility in humans. System evaluation tests demonstrate that the device is MR-compatible with negligible impact on imaging quality [static signal-to-noise ratio (SNR) loss <2.5% and temporal SNR loss <3.5%], and has an accuracy of 99.68% for flow rate and 99.27% for volume delivery. A precise synchronization of the stimulus delivery with fMRI slice acquisition was achieved by programming the proposed device to detect the 5 V transistor–transistor logic (TTL) trigger signals generated by the MRI scanner. The fMRI data analysis using the general linear model analysis with the standard hemodynamic response function showed increased activations in the network of brain regions that included the insula, anterior and mid-cingulate and lateral prefrontal cortices, and thalamus in response to increased distension pressure on viscera. The translation from manually operated devices to an MR-compatible and MR-synchronized device under automatic control represents a useful innovation for clinical neuroimaging studies of human interoception.
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Affiliation(s)
- Behnaz Jarrahi
- Clinic for NeuroradiologyUniversity Hospital ZurichZürich8091Switzerland; Department of Psychiatry and Biobehavioral SciencesSemel Institute for Neuroscience and Human BehaviorUniversity of California at Los AngelesLos AngelesCA90095USA
| | - Roger Gassert
- Department of Health Sciences and Technology Institute of Robotics and Intelligent Systems, ETH Zurich Zürich 8092 Switzerland
| | - Johann Wanek
- Spinal Cord Injury Center Balgrist University Hospital Zürich 8008 Switzerland
| | - Lars Michels
- Clinic for Neuroradiology University Hospital Zurich Zürich 8091 Switzerland
| | - Ulrich Mehnert
- Spinal Cord Injury Center Balgrist University Hospital Zürich 8008 Switzerland
| | - Spyros S Kollias
- Clinic for Neuroradiology University Hospital Zurich Zürich 8091 Switzerland
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10
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Sándor PS, Dydak U, Schoenen J, Kollias SS, Hess K, Boesiger P, Agosti RM. MR-Spectroscopic Imaging during Visual Stimulation in Subgroups of Migraine with Aura. Cephalalgia 2016; 25:507-18. [PMID: 15955037 DOI: 10.1111/j.1468-2982.2005.00900.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Migraine pathophysiology possibly involves deficient mitochondrial energy reserve and diminished cortical habituation. Using functional magnetic resonance spectroscopic imaging (fMRSI), we studied cortical lactate changes during prolonged visual stimulation to search for different pathophysiological mechanisms in clinically distinct subgroups of migraine with aura. Eleven healthy volunteers (HV) and 10 migraine patients were investigated interictally: five with visual aura (MA) and five with visual symptoms and at least one of the following: paraesthe-sia, paresis or dysphasia (MAplus). Using MRSI (Philips, 1.5 T) 1H-spectra were repeatedly obtained from a 25 mm-thick slice covering visual and non-visual cortex, with the first and fifth measurements in darkness and the second to fourth with 8-Hz checkerboard stimulation. In MAplus lactate increased only during stimulation, only in visual cortex; in MA resting lactate was high in visual cortex, without further increase during stimulation. This is compatible with an abnormal metabolic strain during stimulation in MAplus, possibly due to dishabituation, and a predominant mitochondrial dysfunction in MA.
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Affiliation(s)
- P S Sándor
- Neurology Department, University Hospital, Zurich, Switzerland
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11
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Neidert MC, Leske H, Burkhardt JK, Kollias SS, Capper D, Schrimpf D, Regli L, Rushing EJ. Synchronous pituitary adenoma and pituicytoma. Hum Pathol 2016; 47:138-43. [DOI: 10.1016/j.humpath.2015.08.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 08/13/2015] [Accepted: 08/26/2015] [Indexed: 11/24/2022]
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Ahmadli U, Ulrich NH, Yuqiang Y, Nanz D, Sarnthein J, Kollias SS. Early detection of cervical spondylotic myelopathy using diffusion tensor imaging: Experiences in 1.5-tesla magnetic resonance imaging. Neuroradiol J 2015; 28:508-14. [PMID: 26452521 DOI: 10.1177/1971400915609339] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The purpose of this study was to investigate the usefulness of diffusion tensor imaging (DTI) for early detection of pathological alterations in the myelon in patients with cervical spondylotic myelopathy (CSM) without T2-weighted imaging (T2W) signal abnormalities but with a narrowed spinal canal with corresponding clinical correlation. Axial DTI at 1.5T together with routine magnetic resonance imaging was performed on 18 patients fulfilling above mentioned criteria. Quantitative fractional anisotropy (FA) and apparent diffusion coefficient (ADC) maps were generated. Values at the narrowest cervical levels were compared to pre- and poststenotic levels and the interindividual means were tested for statistically significant differences by means of paired t-tests. The correlation between the grade and width of canal stenosis in the axial plane was measured. FA was significantly reduced at the stenotic level, compared to prestenotic level, whereas no significant differences were found when compared to poststenotic level. No significant differences between ADC values at stenotic level versus both adjacent non-stenotic levels were found, suggesting very early stage of degeneration. ADC values correlated significantly with the width of the spinal canal at the prestenotic level, but not at the poststenotic level. Findings indicate sufficient robustness of routine implementation of DTI at 1.5T to detect abnormalities in the spinal cord of CSM patients, before apparent T2W signal abnormalities and marked clinical deterioration. Therefore, larger and long-term studies should be conducted to establish the DTI scalar metrics that would indicate early intervention for a better clinical outcome in patients with clinical signs of CSM.
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Affiliation(s)
- Uzeyir Ahmadli
- Department of Neuroradiology, University Hospital of Zurich, Switzerland
| | - Nils H Ulrich
- Department of Neuroradiology, University Hospital of Zurich, Switzerland Department of Neurosurgery, University Hospital of Zurich, Switzerland
| | - Yao Yuqiang
- Department of Neuroradiology, University Hospital of Zurich, Switzerland
| | - Daniel Nanz
- Institute of Diagnostic and Interventional Radiology, University Hospital of Zurich, Switzerland
| | | | - Spyros S Kollias
- Department of Neuroradiology, University Hospital of Zurich, Switzerland
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13
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Jarrahi B, Mantini D, Balsters JH, Michels L, Kessler TM, Mehnert U, Kollias SS. Differential functional brain network connectivity during visceral interoception as revealed by independent component analysis of fMRI TIME-series. Hum Brain Mapp 2015; 36:4438-68. [PMID: 26249369 DOI: 10.1002/hbm.22929] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 07/20/2015] [Accepted: 07/27/2015] [Indexed: 12/15/2022] Open
Abstract
Influential theories of brain-viscera interactions propose a central role for interoception in basic motivational and affective feeling states. Recent neuroimaging studies have underlined the insula, anterior cingulate, and ventral prefrontal cortices as the neural correlates of interoception. However, the relationships between these distributed brain regions remain unclear. In this study, we used spatial independent component analysis (ICA) and functional network connectivity (FNC) approaches to investigate time course correlations across the brain regions during visceral interoception. Functional magnetic resonance imaging (fMRI) was performed in thirteen healthy females who underwent viscerosensory stimulation of bladder as a representative internal organ at different prefill levels, i.e., no prefill, low prefill (100 ml saline), and high prefill (individually adapted to the sensations of persistent strong desire to void), and with different infusion temperatures, i.e., body warm (∼37°C) or ice cold (4-8°C) saline solution. During Increased distention pressure on the viscera, the insula, striatum, anterior cingulate, ventromedial prefrontal cortex, amygdalo-hippocampus, thalamus, brainstem, and cerebellar components showed increased activation. A second group of components encompassing the insula and anterior cingulate, dorsolateral prefrontal and posterior parietal cortices and temporal-parietal junction showed increased activity with innocuous temperature stimulation of bladder mucosa. Significant differences in the FNC were found between the insula and amygdalo-hippocampus, the insula and ventromedial prefrontal cortex, and the ventromedial prefrontal cortex and temporal-parietal junction as the distention pressure on the viscera increased. These results provide new insight into the supraspinal processing of visceral interoception originating from an internal organ.
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Affiliation(s)
- Behnaz Jarrahi
- Clinic for Neuroradiology, University Hospital, Zurich, Switzerland.,Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, Federal Institute of Technology (ETH), Zurich, Switzerland.,Neuro-Urology Spinal Cord Injury Center and Research, Balgrist University Hospital, Zurich, Switzerland.,Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles (UCLA), California.,Neuroscience Center Zurich, University and ETH, Zurich, Switzerland
| | - Dante Mantini
- Neuroscience Center Zurich, University and ETH, Zurich, Switzerland.,Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom.,Department of Health Sciences and Technology, Neural Control of Movement Laboratory, ETH Zurich, Switzerland
| | - Joshua Henk Balsters
- Department of Health Sciences and Technology, Neural Control of Movement Laboratory, ETH Zurich, Switzerland
| | - Lars Michels
- Clinic for Neuroradiology, University Hospital, Zurich, Switzerland.,Center for MR-Research, University Children's Hospital, Zurich, Switzerland
| | - Thomas M Kessler
- Neuro-Urology Spinal Cord Injury Center and Research, Balgrist University Hospital, Zurich, Switzerland
| | - Ulrich Mehnert
- Neuro-Urology Spinal Cord Injury Center and Research, Balgrist University Hospital, Zurich, Switzerland
| | - Spyros S Kollias
- Clinic for Neuroradiology, University Hospital, Zurich, Switzerland.,Neuroscience Center Zurich, University and ETH, Zurich, Switzerland
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14
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Purohit B, Winder T, Maggio EM, Kollias SS. Aggressive primary olfactory neuroblastoma of the sphenoclival region: a case report and literature review. Laryngoscope 2014; 125:822-5. [PMID: 25215962 DOI: 10.1002/lary.24925] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/07/2014] [Accepted: 08/20/2014] [Indexed: 11/07/2022]
Abstract
Olfactory neuroblastoma (ONB) is an uncommon malignant tumor of neural crest origin, which commonly arises in the superior nasal cavity. Ectopic origin of an ONB is exceedingly rare. We describe a rare case of an ectopic sphenoclival ONB with extensive involvement of the central skull base and with development of systemic metastases. To our knowledge, ours is the first case that describes the imaging features of this rare entity on computed tomography (CT), magnetic resonance imaging, 18 F-fluorodeoxyglucose-positron-emission tomography/CT, and digital subtraction angiography. We also describe the histological features, imaging differentials, and treatment options for this tumor along with a brief literature review.
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Affiliation(s)
- Bela Purohit
- Institute for Neuroradiology, University Hospital of Zurich, Zurich, Switzerland
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15
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Ulrich NH, Ahmadli U, Woernle CM, Alzarhani YA, Bertalanffy H, Kollias SS. Diffusion tensor imaging for anatomical localization of cranial nerves and cranial nerve nuclei in pontine lesions: initial experiences with 3T-MRI. J Clin Neurosci 2014; 21:1924-7. [PMID: 24998855 DOI: 10.1016/j.jocn.2014.03.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 03/15/2014] [Accepted: 03/23/2014] [Indexed: 10/25/2022]
Abstract
With continuous refinement of neurosurgical techniques and higher resolution in neuroimaging, the management of pontine lesions is constantly improving. Among pontine structures with vital functions that are at risk of being damaged by surgical manipulation, cranial nerves (CN) and cranial nerve nuclei (CNN) such as CN V, VI, and VII are critical. Pre-operative localization of the intrapontine course of CN and CNN should be beneficial for surgical outcomes. Our objective was to accurately localize CN and CNN in patients with intra-axial lesions in the pons using diffusion tensor imaging (DTI) and estimate its input in surgical planning for avoiding unintended loss of their function during surgery. DTI of the pons obtained pre-operatively on a 3Tesla MR scanner was analyzed prospectively for the accurate localization of CN and CNN V, VI and VII in seven patients with intra-axial lesions in the pons. Anatomical sections in the pons were used to estimate abnormalities on color-coded fractional anisotropy maps. Imaging abnormalities were correlated with CN symptoms before and after surgery. The course of CN and the area of CNN were identified using DTI pre- and post-operatively. Clinical associations between post-operative improvements and the corresponding CN area of the pons were demonstrated. Our results suggest that pre- and post-operative DTI allows identification of key anatomical structures in the pons and enables estimation of their involvement by pathology. It may predict clinical outcome and help us to better understand the involvement of the intrinsic anatomy by pathological processes.
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Affiliation(s)
- Nils H Ulrich
- Department of Neurosurgery, University Hospital, University of Zurich, Zurich, Switzerland; Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland.
| | - Uzeyir Ahmadli
- Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
| | - Christoph M Woernle
- Department of Neurosurgery, University Hospital, University of Zurich, Zurich, Switzerland
| | - Yahea A Alzarhani
- Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
| | | | - Spyros S Kollias
- Department of Neuroradiology, University Hospital, University of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
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16
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Hock A, Henning A, Kollias SS. Reply: To PMID 23237857. AJNR Am J Neuroradiol 2014; 34:E130. [PMID: 24479160 DOI: 10.3174/ajnr.a3810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Hock A, Fuchs A, Boesiger P, Kollias SS, Henning A. Electrocardiogram-triggered, higher order, projection-based B₀ shimming allows for fast and reproducible shim convergence in spinal cord ¹H MRS. NMR Biomed 2013; 26:329-335. [PMID: 23065738 DOI: 10.1002/nbm.2852] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 08/08/2012] [Accepted: 08/08/2012] [Indexed: 06/01/2023]
Abstract
¹H MRS allows insight into the chemical composition of the central nervous system. However, as a result of technical challenges, it has rarely been applied to the spinal cord. In particular, the strong susceptibility changes around the spinal cord and the pulsatile flow of the cerebrospinal fluid lead to distinct B₀ field distortions which often considerably degrade the spectral quality. Hence, B₀ shimming is one of the main challenges in ¹H MRS of the spinal cord. Electrocardiogram (ECG)-triggered, higher order, projection-based B₀ shimming was introduced and compared with both conventional projection-based B₀ shimming and B₀ shimming based on ECG-triggered, three-dimensional B₀ field mapping. The linewidth of the unsuppressed water peak was used to evaluate the reproducibility and the potential improvement to B₀ homogeneity. The use of ECG-triggered projection-based B₀ shimming in combination with ECG triggering during preparation phases and triggering during acquisition of the spectra is the most robust method and thus helps to improve the spectral quality for MRS of the spinal cord.
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Affiliation(s)
- Andreas Hock
- University and ETH Zurich, Institute for Biomedical Engineering, Gloriastrasse 35 CH-8092 Zurich, Switzerland.
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18
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Hock A, MacMillan EL, Fuchs A, Kreis R, Boesiger P, Kollias SS, Henning A. Non-water-suppressed proton MR spectroscopy improves spectral quality in the human spinal cord. Magn Reson Med 2012; 69:1253-60. [PMID: 22745036 DOI: 10.1002/mrm.24387] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/17/2012] [Accepted: 05/31/2012] [Indexed: 12/14/2022]
Abstract
Magnetic resonance spectroscopy enables insight into the chemical composition of spinal cord tissue. However, spinal cord magnetic resonance spectroscopy has rarely been applied in clinical work due to technical challenges, including strong susceptibility changes in the region and the small cord diameter, which distort the lineshape and limit the attainable signal to noise ratio. Hence, extensive signal averaging is required, which increases the likelihood of static magnetic field changes caused by subject motion (respiration, swallowing), cord motion, and scanner-induced frequency drift. To avoid incoherent signal averaging, it would be ideal to perform frequency alignment of individual free induction decays before averaging. Unfortunately, this is not possible due to the low signal to noise ratio of the metabolite peaks. In this article, frequency alignment of individual free induction decays is demonstrated to improve spectral quality by using the high signal to noise ratio water peak from non-water-suppressed proton magnetic resonance spectroscopy via the metabolite cycling technique. Electrocardiography (ECG)-triggered point resolved spectroscopy (PRESS) localization was used for data acquisition with metabolite cycling or water suppression for comparison. A significant improvement in the signal to noise ratio and decrease of the Cramér Rao lower bounds of all metabolites is attained by using metabolite cycling together with frequency alignment, as compared to water-suppressed spectra, in 13 healthy volunteers.
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Affiliation(s)
- Andreas Hock
- Departament of Information Technology and Electrical Engineering, University and ETH Zurich, and Institute of Neuroradiology, University Hospital of Zurich, Zurich, Switzerland.
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19
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Burkhardt JK, Holzmann D, Strobl L, Woernle CM, Bosch MM, Kollias SS, Reisch R. Interdisciplinary endoscopic assisted surgery of a patient with a complete transorbital intracranial impalement through the dominant hemisphere. Childs Nerv Syst 2012; 28:951-4. [PMID: 22407385 DOI: 10.1007/s00381-011-1674-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 12/28/2011] [Indexed: 11/28/2022]
Affiliation(s)
- Jan-Karl Burkhardt
- Department of Neurosurgery, University Hospital, University of Zurich, Zurich, Switzerland
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20
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Hotz-Boendermaker S, Hepp-Reymond MC, Curt A, Kollias SS. Movement Observation Activates Lower Limb Motor Networks in Chronic Complete Paraplegia. Neurorehabil Neural Repair 2011; 25:469-76. [DOI: 10.1177/1545968310389184] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background. In healthy subjects, observation of actions activates a motor network similar to that involved in the performance of the observed actions. Movement observation could perhaps be applied to functionally sustain brain motor functions when efferent motor commands and proprioceptive feedbacks are disconnected. Objective. The authors examined whether observation-induced brain activation is preserved in people with chronic complete spinal cord injury (SCI). Methods. Nine patients and 12 healthy subjects underwent behavioral assessment and functional magnetic resonance imaging. The SCI patients attempted to perform dorsal and plantar flexions of the right foot, and the controls also executed the same movement. Both groups observed subsequent video clips showing the same movement. Results. In the SCI group, attempted and observed foot movements activated a common observation–execution network including ventral premotor, parietal cortex, and cerebellum as in healthy subjects. Conclusions. Long after onset of complete SCI, the brain maintains its ability to respond to task-specific visual inputs, which suggests preservation of motor programs. This persistence might be a prerequisite for repair strategies of the spinal cord that rely on appropriate activation of the brain to try to restore limb function. The preserved cortical network may offer an additional motor rehabilitation approach for people with SCI.
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Affiliation(s)
- Sabina Hotz-Boendermaker
- Balgrist University Hospital Zurich, Zurich, Switzerland
- University Hospital Zurich, Zurich, Switzerland
| | | | - Armin Curt
- Balgrist University Hospital Zurich, Zurich, Switzerland
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21
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Keisker B, Hepp-Reymond MC, Blickenstorfer A, Kollias SS. Differential representation of dynamic and static power grip force in the sensorimotor network. Eur J Neurosci 2010; 31:1483-91. [PMID: 20384781 DOI: 10.1111/j.1460-9568.2010.07172.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Previous studies investigating the blood oxygen level-dependent (BOLD) signal in the human sensorimotor cortex during static force (maintained for a few seconds) and dynamic force (repetitive force pulses) resulted in contradictory findings. Therefore, we conducted a whole-brain functional magnetic resonance imaging study during a visuomotor task requiring the production of either dynamic or static power grip force. Thereby we aimed at clarifying whether the BOLD signal behaves differently with dynamic and static force in the primary motor cortex, and whether it behaves in the same way in all areas and regions involved in force production. In the static condition, participants applied visually guided, isometric grip force on a dynamometer of 20% maximal voluntary contraction (MVC) and held this force for 21 s. In the dynamic condition, self-paced force pulses of 20% MVC were produced at a rate of 0.5 Hz. Static and dynamic force production activated an overlapping network of sensorimotor cortical and subcortical regions. However, the production of a significantly higher mean static force compared with the dynamic force resulted in a significantly smaller BOLD signal in the contralateral motor cortex, confirming observations of an earlier investigation. In addition, we found that the ipsilateral anterior cerebellum behaved similar to the motor cortex, whereas in all other activated regions the activation during static and dynamic force did not significantly differ. These findings demonstrate that various regions of the sensorimotor network participate differentially in the production and control of low static and dynamic grip force, and raise important questions concerning the interpretation of the BOLD signal with respect to mechanisms of neurovascular coupling.
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Affiliation(s)
- Birgit Keisker
- Institute of Neuroradiology, University Hospital Zurich, Zurich, Switzerland.
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22
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Hollnagel DI, Summers PE, Poulikakos D, Kollias SS. Comparative velocity investigations in cerebral arteries and aneurysms: 3D phase-contrast MR angiography, laser Doppler velocimetry and computational fluid dynamics. NMR Biomed 2009; 22:795-808. [PMID: 19412933 DOI: 10.1002/nbm.1389] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In western populations, cerebral aneurysms develop in approximately 4% of humans and they involve the risk of rupture. Blood flow patterns are of interest for understanding the pathogenesis of the lesions and may eventually contribute to deciding on the most efficient treatment procedure for a specific patient. Velocity mapping with phase-contrast magnetic resonance angiography (PC-MRA) is a non-invasive method for performing in vivo measurements on blood velocity. Several hemodynamic properties can either be derived directly from these measurements or a flow field with all its parameters can be simulated on the basis of the measurements. For both approaches, the accuracy of the PC-MRA data and subsequent modeling must be validated. Therefore, a realistic transient flow field in a well-defined patient-specific silicone phantom was investigated. Velocity investigations with PC-MRA in a 3 Tesla MR scanner, laser Doppler velocimetry (LDV) and computational fluid dynamics (CFD) were performed in the same model under equal flow conditions and compared to each other. The results showed that PC-MRA was qualitatively similar to LDV and CFD, but showed notable quantitative differences, while LDV and CFD agreed well. The accuracy of velocity quantification by PC-MRA was best in straight artery regions with the measurement plane being perpendicular to the primary flow direction. The accuracy decreased in regions with disturbed flow and in cases where the measurement plane was not perpendicular to the primary flow. Due to these findings, it is appropriate to use PC-MRA as the inlet and outlet conditions for numerical simulations to calculate velocities and shear stresses in disturbed regions like aneurysms, rather than derive these values directly from the full PC-MRA measured velocity field.
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23
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Keisker B, Hepp-Reymond MC, Blickenstorfer A, Meyer M, Kollias SS. Differential force scaling of fine-graded power grip force in the sensorimotor network. Hum Brain Mapp 2009; 30:2453-65. [PMID: 19172654 DOI: 10.1002/hbm.20676] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Force scaling in the sensorimotor network during generation and control of static or dynamic grip force has been the subject of many investigations in monkeys and human subjects. In human, the relationship between BOLD signal in cortical and subcortical regions and force still remains controversial. With respect to grip force, the modulation of the BOLD signal has been mostly studied for forces often reaching high levels while little attention has been given to the low range for which electrophysiological neuronal correlates have been demonstrated. We thus conducted a whole-brain fMRI study on the control of fine-graded force in the low range, using a power grip and three force conditions in a block design. Participants generated on a dynamometer visually guided repetitive force pulses (ca. 0.5 Hz), reaching target forces of 10%, 20%, and 30% of maximum voluntary contraction. Regions of interest analysis disclosed activation in the entire cortical and subcortical sensorimotor network and significant force-related modulation in several regions, including primary motor (M1) and somatosensory cortex, ventral premotor and inferior parietal areas, and cerebellum. The BOLD signal, however, increased monotonically with force only in contralateral M1 and ipsilateral anterior cerebellum. The remaining regions were activated with force in various nonlinear manners, suggesting that other factors such as visual input, attention, and muscle recruitment also modulate the BOLD signal in this visuomotor task. These findings demonstrate that various regions of the sensorimotor network participate differentially in the production and control of fine-graded grip forces.
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Affiliation(s)
- Birgit Keisker
- Institute of Neuroradiology, University Hospital Zurich, Zurich, Switzerland.
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24
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Benninger DH, Thees S, Kollias SS, Bassetti CL, Waldvogel D. Morphological differences in Parkinson's disease with and without rest tremor. J Neurol 2009; 256:256-63. [PMID: 19219572 DOI: 10.1007/s00415-009-0092-2] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 07/08/2008] [Accepted: 08/21/2008] [Indexed: 01/18/2023]
Abstract
BACKGROUND Rest tremor is a hallmark of Parkinson's disease (PD), but its pathogenesis remains incompletely understood. Nigro-striatal dopamine deficiency correlates best with bradykinesia, but not with tremor. Oscillating neurons in one or multiple localizations within the basal gangliathalamo-cortical loop may cause rest tremor, and an active contribution of the cerebellum and the cerebello-thalamo-cortical projections has been postulated. OBJECTIVE To compare the pattern of grey matter volume in PD patients with and without tremor to identify structural correlates of rest tremor. METHODS Voxel-based morphometry (VBM) of a high-resolution 3 Tesla, T1-weighted MR images, pre-processed according to an optimized protocol using SPM2, was performed in 24 patients with mild to moderate PD comparing local grey matter volume in patients with (n = 14) and without rest tremor (n = 10). RESULTS Grey matter volume is decreased in the right quadrangular lobe and declive of the cerebellum in PD with tremor compared to those without (PFDR < 0.05). CONCLUSIONS These results demonstrate for the first time morphological changes in the cerebellum in PD patients with rest tremor and highlight the involvement of the cerebellum and cerebello- thalamo-cortical circuit in the pathogenesis of parkinsonian rest tremor.
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Affiliation(s)
- David H Benninger
- Human Motor Control Section, Medical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Building 10 Room 5N240 (MSC1428), Center Drive, Bethesda, MD 20892, USA.
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25
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Abstract
In spite of their diagnostic potential, the poor quality of available diffusion-weighted spinal cord images often restricts clinical application to cervical regions, and improved spatial resolution is highly desirable. To address these needs, a novel technique based on the combination of two recently presented reduced field-of-view approaches is proposed, enabling high-resolution acquisition over the entire spinal cord. Field-of-view reduction is achieved by the application of non-coplanar excitation and refocusing pulses combined with outer volume suppression for removal of unwanted transition zones. The non-coplanar excitation is performed such that a gap-less volume is acquired in a dedicated interleaved slice order within two repetition times. The resulting inner volume selectivity was evaluated in vitro. In vivo diffusion tensor imaging data on the cervical, thoracic and lumbar spinal cord were acquired in transverse orientation in each of four healthy subjects. An in-plane resolution of 0.7 x 0.7 mm(2) was achieved without notable aliasing, motion or susceptibility artifacts. The measured mean +/- SD fractional anisotropy was 0.69 +/- 0.11 in the thoracic spinal cord and 0.75 +/- 0.07 and 0.63 +/- 0.08 in cervical and lumbar white matter, respectively.
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Affiliation(s)
- B J Wilm
- Institute for Biomedical Engineering, University and ETH Zurich, Switzerland.
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26
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Henning A, Schär M, Kollias SS, Boesiger P, Dydak U. Quantitative magnetic resonance spectroscopy in the entire human cervical spinal cord and beyond at 3T. Magn Reson Med 2008; 59:1250-8. [PMID: 18421679 DOI: 10.1002/mrm.21578] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Quantitative magnetic resonance spectroscopy (MRS) amends differential diagnostics of neurological pathology. However, due to technical challenges, it has rarely been applied to the spinal cord and has mainly been restricted to the very upper part of the cervical spine. In this work, an improved acquisition protocol is proposed that takes technical problems as strong magnetic field inhomogeneities, pulsatile flow of the cerebrospinal fluid (CSF), and small voxel size into account. For that purpose, inner-volume saturated point-resolved spectroscopy sequence (PRESS) localization, ECG triggering, and localized higher-order shimming and F0 determination, based on high-resolution cardiac-triggered static magnetic field B0 mapping, are combined. For inner-volume saturation a highly selective T1- and B1-insensitive outer-volume suppression (OVS) sequence based on broadband RF pulses with polynomial-phase response (PPR) is used. Validation is performed in healthy volunteers and patients with multiple sclerosis and intramedullary tumors. The applicability of spinal cord MRS is extended to the entire cervical spine. Spectral quality and its consistency are improved. In addition, high quality MRS patient data from a lesion that occluded the spinal canal in the thoracic spinal cord could be acquired. A quantitative analysis of patient spectra and spectra from healthy volunteers at different positions along the spinal cord underlines the diagnostic value of spinal cord MRS.
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Affiliation(s)
- Anke Henning
- Institute for Biomedical Engineering, University and Federal Institute of Technology (ETH) Zurich, and Neuroradiology, University Hospital Zurich, Zurich, Switzerland.
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27
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Funk M, Lutz K, Hotz-Boendermaker S, Roos M, Summers P, Brugger P, Hepp-Reymond MC, Kollias SS. Sensorimotor tongue representation in individuals with unilateral upper limb amelia. Neuroimage 2008; 43:121-7. [DOI: 10.1016/j.neuroimage.2008.06.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 05/30/2008] [Accepted: 06/04/2008] [Indexed: 11/28/2022] Open
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28
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Hollnagel DI, Summers PE, Kollias SS, Poulikakos D. Laser Doppler velocimetry (LDV) and 3D phase-contrast magnetic resonance angiography (PC-MRA) velocity measurements: validation in an anatomically accurate cerebral artery aneurysm model with steady flow. J Magn Reson Imaging 2008; 26:1493-505. [PMID: 17968887 DOI: 10.1002/jmri.21179] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
PURPOSE To verify the accuracy of velocity mapping with three-dimensional (3D) phase-contrast magnetic resonance angiography (PC-MRA) for steady flow in a realistic model of a cerebral artery aneurysm at a 3T scanner. MATERIALS AND METHODS Steady flow through an original geometry model of a cerebral aneurysm was mapped at characteristic positions by state-of-the-art laser Doppler velocimetry (LDV) as well as 3D PC-MRA at 3T. The spatial distributions and local values of two velocity components obtained with these two measurement methods were compared. RESULTS The 3D PC-MRA velocity field distribution and mean velocity values exhibited only minor differences to compare to the LDV measurements in straight artery regions for both main and secondary velocities. The differences increased in regions with disturbed flow and in cases where the measurement plane was not perpendicular to the main flow direction. CONCLUSION 3D PC-MRA can provide reliable measurements of velocity components of steady flow in small arteries. The accuracy of such measurements depends on the artery size and the measurement plane positioning.
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Affiliation(s)
- Dorothea I Hollnagel
- Laboratory of Thermodynamics in Emerging Technologies, ETH Zurich, Zurich, Switzerland
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29
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Abstract
We describe three cases of parotid gland lipoma, a relatively rare, asymptomatic, slow growing, freely movable, soft tissue mass. Preoperative clinical diagnosis is generally difficult but MRI using fat saturation techniques provides accurate diagnostic information regarding this benign parotid gland tumor, enabling better treatment planning.
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Affiliation(s)
- N Husain
- Institute of Neuroradiology, University Hospital of Zurich; Switzerland -
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30
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Lawrence JM, Stroman PW, Kollias SS. Functional magnetic resonance imaging of the human spinal cord during vibration stimulation of different dermatomes. Neuroradiology 2007; 50:273-80. [PMID: 18026942 DOI: 10.1007/s00234-007-0338-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Accepted: 10/26/2007] [Indexed: 11/30/2022]
Abstract
INTRODUCTION We investigated noninvasively areas of the healthy human spinal cord that become active in response to vibration stimulation of different dermatomes using functional magnetic resonance imaging (fMRI). The objectives of this study were to: (1) examine the patterns of consistent activity in the spinal cord during vibration stimulation of the skin, and (2) investigate the rostrocaudal distribution of active pixels when stimulation was applied to different dermatomes. METHODS FMRI of the cervical and lumbar spinal cord of seven healthy human subjects was carried out during vibration stimulation of six different dermatomes. In separate experiments, vibratory stimulation (about 50 Hz) was applied to the right biceps, wrist, palm, patella, Achilles tendon and left palm. RESULTS The segmental distribution of activity observed by fMRI corresponded well with known spinal cord neuroanatomy. The peak number of active pixels was observed at the expected level of the spinal cord with some activity in the adjacent segments. The rostrocaudal distribution of activity was observed to correspond to the dermatome being stimulated. Cross-sectional localization of activity was primarily in dorsal areas but also spread into ventral and intermediate areas of the gray matter and a distinct laterality ipsilateral to the stimulated limb was not observed. CONCLUSION We demonstrated that fMRI can detect a dermatome-dependent pattern of spinal cord activity during vibratory stimulation and can be used as a passive stimulus for the noninvasive assessment of the functional integrity of the human spinal cord. Demonstration of cross-sectional selectivity of the activation awaits further methodological and experimental refinements.
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Affiliation(s)
- Jane M Lawrence
- Institute of Neuroradiology, University Hospital of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
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Jaermann T, De Zanche N, Staempfli P, Pruessmann KP, Valavanis A, Boesiger P, Kollias SS. Preliminary experience with visualization of intracortical fibers by focused high-resolution diffusion tensor imaging. AJNR Am J Neuroradiol 2007; 29:146-50. [PMID: 17947372 DOI: 10.3174/ajnr.a0742] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The inherent low anisotropy of gray matter and the lack of adequate imaging sensitivity and resolution has, so far, impeded depiction of axonal fibers to their intracortical origin or termination. We tested the hypothesis that an experimental approach with high-resolution diffusion tensor imaging (DTI) provides anisotropic data for fiber tractography with sufficient sensitivity to visualize in vivo the fine distribution of white matter bundles at the intracortical level. MATERIALS AND METHODS We conducted phantom measurements of signal-to-noise ratio (SNR) and obtained diffusion tensor maps of the occipital lobe in 6 healthy volunteers using a dedicated miniature phased array detector at 3T. We reconstructed virtual fibers using a standard tracking algorithm. RESULTS The coil array provided a SNR of 8.0 times higher at the head surface compared with a standard quadrature whole head coil. Diffusion tensor maps could be obtained with an in-plane resolution of 0.58 x 0.58 mm(2). The axonal trajectories reconstructed from the diffusion data penetrate into the cortical ribbon perpendicular to the pial surface. This is the expected pattern for the terminations of thalamocortical afferent fibers to the middle layers of the occipital cortex and is consistent with the known microstructural organization of the mammalian cerebral cortex. CONCLUSION High-resolution DTI reveals intracortical anisotropy with a distinct parallel geometrical order, perpendicular to the pial surface, consistent with structures that may be identified as the terminal afferents in cortical gray matter.
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Affiliation(s)
- T Jaermann
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
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Wilm BJ, Svensson J, Henning A, Pruessmann KP, Boesiger P, Kollias SS. Reduced field-of-view MRI using outer volume suppression for spinal cord diffusion imaging. Magn Reson Med 2007; 57:625-30. [PMID: 17326167 DOI: 10.1002/mrm.21167] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A spin-echo single-shot echo-planar imaging (SS-EPI) technique with a reduced field of view (FOV) in the phase-encoding direction is presented that simultaneously reduces susceptibility effects and motion artifacts in diffusion-weighted (DW) imaging (DWI) of the spinal cord at a high field strength (3T). To minimize aliasing, an outer volume suppression (OVS) sequence was implemented. Effective fat suppression was achieved with the use of a slice-selection gradient-reversal technique. The OVS was optimized by numerical simulations with respect to T(1) relaxation times and B(1) variations. The optimized sequence was evaluated in vitro and in vivo. In simulations the optimized OVS showed suppression to <0.25% and approximately 3% in an optimal and worst-case scenario, respectively. In vitro measurements showed a mean residual signal of <0.95% +/- 0.42 for all suppressed areas. In vivo acquisition with 0.9 x 1.05 mm(2) in-plane resolution resulted in artifact-free images. The short imaging time of this technique makes it promising for clinical studies.
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Affiliation(s)
- B J Wilm
- Institute of Neuroradiology, University Hospital Zurich, Zurich, Switzerland.
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Thees S, Benninger D, Bassetti C, Kahn T, Kollias SS, Waldvogel D. Vergleich der kortikalen Morphologie des primär akinetisch-rigiden und des primär tremor-dominaten M.Parkinson. ROFO-FORTSCHR RONTG 2007. [DOI: 10.1055/s-2007-977113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Wienbruch C, Candia V, Svensson J, Kleiser R, Kollias SS. A portable and low-cost fMRI compatible pneumatic system for the investigation of the somatosensensory system in clinical and research environments. Neurosci Lett 2006; 398:183-8. [PMID: 16469438 DOI: 10.1016/j.neulet.2006.01.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Revised: 10/20/2005] [Accepted: 01/10/2006] [Indexed: 10/25/2022]
Abstract
There still is a need for devices that allow reproducible stimulation of skin areas of the human body. We constructed a stimulation system and tested it by using brief pneumatic stimulation to the right thumb of nine healthy volunteers. BOLD-signals in response to tactile stimulation with frequencies of 1, 3 and 5 Hz were measured using a 3T MRI scanner. The stimulation device consists of synthetic membranes connected to plastic tubes capable of carrying compressed air, and an electronic component, which controls the on- and off-switching of an electromagnetic valve. The valve near the MR-scanner did not lower the image quality. Primary somatosensory activation contralateral to the stimulation site was reliably detected in response to a stimulus magnitude of 3.5 bar in all volunteers. 1 Hz stimulation resulted in higher maximal percentage BOLD-signal changes. Our device is an easy-to-construct, low-cost and portable tool suitable for research and clinical environments. It permits passive non-painful stimulation relevant for clinical assessments and is also compatible with magnetoencephalography (MEG) and electroencephalography (EEG). In basic and clinical research, this device therefore contributes to meaningful comparisons between results obtained with different techniques.
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Affiliation(s)
- Christian Wienbruch
- Department of Psychology, University of Konstanz, Fach D25, D-78457 Konstanz, Germany, and Institute of Neuroradiology, University Hospital of Zurich, Switzerland
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Patzwahl R, Landau K, Kollias SS. Atypical midface tumor complicating nevus of ota. AJNR Am J Neuroradiol 2005; 26:2117-21. [PMID: 16155168 PMCID: PMC8148863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In the differential diagnosis of midface masses, the nevus of Ota (also called oculodermal melanocytosis) is a rare entity. We present a case of a young white man, who lost his left eye function by progression of a melanocytotic lesion involving the ophthalmic (VI) and maxillary (VII) divisions of the trigeminal nerve. The time course, distribution along the trigeminal nerve, and characteristic MR signal intensities of the lesion, in correlation with the clinical, ophthalmological, and dermatological findings, point to the correct diagnosis.
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Affiliation(s)
- René Patzwahl
- Institute of Neuroradiology and the Department of Ophthalmology, University Hospital of Zürich, Zürich, Switzerland
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36
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Alkadhi H, Brugger P, Boendermaker SH, Crelier G, Curt A, Hepp-Reymond MC, Kollias SS. What Disconnection Tells about Motor Imagery: Evidence from Paraplegic Patients. Cereb Cortex 2004; 15:131-40. [PMID: 15238440 DOI: 10.1093/cercor/bhh116] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Brain activation during motor imagery has been the subject of a large number of studies in healthy subjects, leading to divergent interpretations with respect to the role of descending pathways and kinesthetic feedback on the mental rehearsal of movements. We investigated patients with complete spinal cord injury (SCI) to find out how the complete disruption of motor efferents and sensory afferents influences brain activation during motor imagery of the disconnected feet. Eight SCI patients underwent behavioral assessment and functional magnetic resonance imaging. When compared to a healthy population, stronger activity was detected in primary and all non-primary motor cortical areas and subcortical regions. In paraplegic patients the primary motor cortex was consistently activated, even to the same degree as during movement execution in the controls. Motor imagery in SCI patients activated in parallel both the motor execution and motor imagery networks of healthy subjects. In paraplegics the extent of activation in the primary motor cortex and in mesial non-primary motor areas was significantly correlated with the vividness of movement imagery, as assessed by an interview. The present findings provide new insights on the neuroanatomy of motor imagery and the possible role of kinesthetic feedback in the suppression of cortical motor output required during covert movements.
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Affiliation(s)
- Hatem Alkadhi
- Institute of Neuroradiology, University Hospital Zurich, CH-8091 Zurich, Switzerland
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Keller E, Nadler A, Alkadhi H, Kollias SS, Yonekawa Y, Niederer P. Erratum to “Noninvasive measurement of regional cerebral blood flow and regional cerebral blood volume by near-infrared spectroscopy and indocyanine green dye dilution” [NeuroImage 20 (2003) 828–839]. Neuroimage 2004. [DOI: 10.1016/j.neuroimage.2004.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Kollias SS. Investigations of the human visual system using functional magnetic resonance imaging (FMRI). Eur J Radiol 2004; 49:64-75. [PMID: 14975494 DOI: 10.1016/j.ejrad.2003.09.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2003] [Revised: 09/08/2003] [Accepted: 09/09/2003] [Indexed: 10/26/2022]
Abstract
The application of functional magnetic resonance imaging (fMRI) in studies of the visual system provided significant advancement in our understanding of the organization and functional properties of visual areas in the human cortex. Recent technological and methodological improvements allowed studies to correlate neuronal activity with visual perception and demonstrated the ability of fMRI to observe distributed neural systems and to explore modulation of neural activity during higher cognitive processes. Preliminary applications in patients with visual impairments suggest that this method provides a powerful tool for the assessment and management of brain pathologies. Recent research focuses on obtaining new information about the spatial localization, organization, functional specialization and participation in higher cognitive functions of visual cortical areas in the living human brain and in further establishment of the method as a useful clinical tool of diagnostic and prognostic significance for various pathologic processes affecting the integrity of the visual system. It is anticipated that the combined neuroimaging approach in patients with lesions and healthy controls will provide new insight on the topography and functional specialization of cortical visual areas and will further establish the clinical value of the method for improving diagnostic accuracy and treatment planning.
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Affiliation(s)
- Spyros S Kollias
- Institute of Neuroradiology, University Hospital of Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland.
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Alkadhi H, Rissmann D, Kollias SS. Osteogenesis imperfecta of the temporal bone: CT and MR imaging in Van der Hoeve-de Kleyn syndrome. AJNR Am J Neuroradiol 2004; 25:1106-9. [PMID: 15205159 PMCID: PMC7975648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
We report the progressive otic capsule demineralization around the membranous labyrinth and facial nerve in an adult patient with osteogenesis imperfecta tarda. Whereas the initial CT scan showed bandlike, undermineralized pericochlear areas, 2 years later, repeat CT performed because of hearing deterioration showed progression of these findings to the promontory, the round window niche, and the labyrinthine and tympanic segments of the facial nerve canal. MR imaging demonstrated enhancement of the abnormal otic capsule and of the intratemporal and canalicular facial nerve. The differential diagnosis of osteogenesis imperfecta tarda affecting the temporal bone includes otosclerosis, Paget disease, otosyphilis, and Camurati-Engelmann disease.
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Affiliation(s)
- Hatem Alkadhi
- Institute of Neuroradiology, University Hospital Zurich, Zurich, Switzerland
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Roelcke U, Alkadhi H, Tröger M, Hungerbühler H, Kollias SS. Normal brain activation in hemiatrophy due to multiple sclerosis: a functional MRI case study. Eur Neurol 2004; 51:191-5. [PMID: 15159598 DOI: 10.1159/000078484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2003] [Accepted: 02/09/2004] [Indexed: 11/19/2022]
Abstract
Evidence from recent functional magnetic resonance imaging studies suggests that adaptive cortical changes ('plasticity') could participate in the maintenance of function in multiple sclerosis (MS). Here, we addressed the impact of brain atrophy on the pattern of cerebral activation in an MS patient with a relapsing-remitting course. This patient showed mildly disabling hemiparesis of the left side (EDSS 2.0), and corresponding brain hemiatrophy (15% volume reduction) of the right hemisphere. The clinical syndrome was considered to result from a lesion in the corona radiata involving corticospinal fibers. Motor-evoked potential recordings confirmed substantial axonal damage to the pyramidal tract arising from that hemisphere. Irrespective of these asymmetries, normal brain activation was found for hand and foot movements for both brain sides. This demonstrates that brain atrophy itself does not necessarily induce cortical adaptive changes, even if mild disability is present. On the other hand, significantly disabling distinct clinical syndromes e.g. arising from spinal cord lesions may evoke cortical changes irrespective of brain atrophy. This issue has to be studied in longitudinal investigations.
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Affiliation(s)
- U Roelcke
- Department of Neurology, Cantonal Hospital, Aarau, Switzerland.
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Alkadhi H, Kollias SS. Pli de passage fronto-pariétal moyen of broca separates the motor homunculus. AJNR Am J Neuroradiol 2004; 25:809-12. [PMID: 15140726 PMCID: PMC7974465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
The complete form of the pli de passage fronto-pariétal moyen of Broca, a gyrus connecting the pre- and postcentral gyri at the level of the presumable primary motor (M1) hand area, represents a rare anatomic variation. By using functional MR imaging in a healthy subject incidentally found to harbor this configuration, we attempted to determine whether such an accessory gyrus would be functionally active and what effect it has on the complex somatotopic within-arm organization of M1. We found a specific and consistent activation pattern along the lateral and medial cortical boundaries of the pli de passage fronto-pariétal moyen. The gyrus completely segregated the M1 finger from the M1 elbow representation, one being laterally and the other medially located. Furthermore the M1 wrist representation was consistently split by the pli de passage fronto-pariétal moyen into a medial and lateral activation cluster. These findings demonstrate that this accessory gyrus not only contains functionally active neurons, but also leads to a functional separation of the motor homunculus at the level of the M1 wrist representation. This is a remarkable finding, because the region of within-arm representations in M1 was previously thought to be necessarily organized in a complex and intermingled fashion, without a topographic segregation between single body parts.
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Affiliation(s)
- H Alkadhi
- Institute of Neuroradiology, University Hospital Zurich, Switzerland
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Baumann F, Bjeljac M, Kollias SS, Baumert BG, Brandner S, Rousson V, Yonekawa Y, Bernays RL. Combined Thalidomide and Temozolomide Treatment in Patients with Glioblastoma Multiforme. J Neurooncol 2004; 67:191-200. [PMID: 15072467 DOI: 10.1023/b:neon.0000021803.01170.03] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVES Glioblastoma multiforme (GBM) may potentially be responsive to antiangiogenic therapies as these tumors are highly vascularized and overexpress angiogenic factors. Thalidomide exhibits antiangiogenic activity and may provide additive or synergistic antitumor effects when given concurrently with temozolomide, an alkylating agent. To further evaluate this new concept of combining an antiangiogenic with an alkylating agent, efficacy and tolerability of thalidomide alone and in combination with temozolomide were explored in a single-institution, nonrandomized open-label phase II study. PATIENTS AND METHODS Forty-four patients with GBMs, who received thalidomide for a period of at least three months, were evaluated for survival, time to tumor progression (TTP), and side effects. Microsurgical tumor extirpation and radiotherapy preceded chemotherapy. Nineteen patients (43%) received thalidomide only (T), and 25 patients (57%) had a combined chemotherapy of thalidomide and temozolomide (TT). Median thalidomide dosage was 200 mg/day. Median temozolomide dosage was 200 mg/m2/day for five days, in monthly cycles. Neuroradiological outcomes were assessed by a semiquantitative grading system. RESULTS Median survival was 103 weeks (95% CI, 65-141 weeks) for TT-patients and 63 weeks (95% CI, 49-77 weeks) for T-patients (p < 0.01). Median TTP for the TT-group was 36 weeks (95% CI, 20-52 weeks) and 17 weeks (95% CI, 13-21 weeks) for the T-group (p < 0.06). Neuroradiologically, 14 patients (56%) of the TT-group and six (32%) of the T-group had evidence of stable disease on at least two successive neuroradiological follow-ups. Progressive disease was found in nine patients (36%) of the TT-group and in 13 (68%) of the T-group. In two patients (8%) of the TT-group, a response with tumor regression was found. Thalidomide and concurrent temozolomide were safe and well tolerated with mild to moderate toxicities. CONCLUSIONS The combination of thalidomide and temozolomide in the treatment of GBM appears to be more effective than that of thalidomide alone with respect to survival, TTP, and neuroradiological documentation of progression, stable disease or response. Further concurrent prospective studies of these agents in a larger group of patients with GBM will be required to establish the soundness of these intriguing observations.
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Affiliation(s)
- Fabian Baumann
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland
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Summers PE, Kollias SS, Valavanis A. Resolution improvement in thick-slab magnetic resonance digital subtraction angiography using SENSE at 3T. J Magn Reson Imaging 2004; 20:662-73. [PMID: 15390145 DOI: 10.1002/jmri.20156] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To evaluate the use of parallel imaging (sensitivity encoding [SENSE]) to improve spatial resolution and achieve sub-second temporal resolution in fluoroscopic contrast-enhanced, magnetic resonance digital subtraction angiography (MR-DSA). MATERIALS AND METHODS A MR-DSA sequence was optimized on a 3-T scanner with respect to sampling bandwidth and SENSE acceleration factor subject to the constraints of half-second acquisition time and 0.6 x 1.2 mm in-plane resolution. MR-DSA with and without SENSE acceleration was then evaluated in patients with arterio-venous malformations (AVMs). RESULTS Consistent with previously reported results and theory, SENSE factors greater than two and increasing sampling bandwidth both led to increasing image noise. Compared to lower resolution MR-DSA images with similar temporal resolution, the SENSE accelerated sequence provided better spatial resolution without notable changes in the contrast enhancement of the vascular territories of the AVMs but was hampered somewhat in the late venous phases by a reconstruction artifact. CONCLUSION SENSE acceleration of MR-DSA by a factor of two allows improved temporal or spatial resolution without significant loss of image quality. Signal-to-noise degradation associated with higher SENSE acceleration factors are likely to necessitate other approaches to further improving resolution in MR-DSA. Clinically, SENSE accelerated MR-DSA improves the non-invasive pre- and postoperative depiction of AVM flow dynamics.
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Affiliation(s)
- Paul E Summers
- Institute of Neuroradiology, University Hospital Zurich, Zurich, Switzerland.
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Keller E, Nadler A, Alkadhi H, Kollias SS, Yonekawa Y, Niederer P. Noninvasive measurement of regional cerebral blood flow and regional cerebral blood volume by near-infrared spectroscopy and indocyanine green dye dilution. Neuroimage 2003; 20:828-39. [PMID: 14568455 DOI: 10.1016/s1053-8119(03)00315-x] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2002] [Accepted: 05/28/2003] [Indexed: 12/16/2022] Open
Abstract
To find a suitable method for measuring regional cerebral blood flow (rCBF) rapidly at the bedside is still a matter of investigation. The purpose here was to develop a noninvasive method for bedside rCBF measurement and to validate it with a standard method such as perfusion-weighted magnetic resonance imaging (MRI). In 11 healthy volunteers 44 measurements with near-infrared spectroscopy (NIRS) and perfusion-weighted MRI without and with a mean continuous positive airway pressure (CPAP) of 10 mbar were carried out. Four (NIRS) optodes were placed bilaterally on the forehead and 25 mg indocyanine green (ICG) was injected. New algorithms were developed to calculate rCBFNIRS and rCBVNIRS. In 6 volunteers data analysis was successful. No complications associated with the method were observed. During CPAP breathing rCBFNIRS decreased from 18.5 + 6.9 16.1 + 6.2 ml/100 g/min (P = 0.034). Mean values for rCBFMRI decreased from 256 +/- 90 to 216 +/- 62 ml/100 g/min (P = 0.012). Bland and Altman plots showed that the differences did not vary in any systematic way over the range of rCBF or rCBV values assessed and 100% of differences were within the interval mean +/- 2 SD of differences. Limits of agreement (mean +/- 2 SD) were +/- 76.4 ml/100 g/min for rCBF and +/- 15.6 ml/100 g for rCBV. The NIRS ICG dye dilution technique is a promising method for serial noninvasive bedside CBF measurements. The preliminary data indicate that measurements are in agreement with values obtained by perfusion-weighted MRI.
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Affiliation(s)
- Emanuela Keller
- Department of Neurosurgery, University Hospital of Zurich, Zurich, Switzerland.
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Jung HH, Hergersberg M, Vogt M, Pahnke J, Treyer V, Röthlisberger B, Kollias SS, Russo D, Frey BM. McLeod phenotype associated with a XK missense mutation without hematologic, neuromuscular, or cerebral involvement. Transfusion 2003; 43:928-38. [PMID: 12823753 DOI: 10.1046/j.1537-2995.2003.t01-1-00434.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The X-linked McLeod neuroacanthocytosis syndrome is a multisystem disorder with hematologic, neuromuscular, and central nervous system (CNS) manifestations. All carriers of the McLeod blood group phenotype examined so far had at least subclinical signs of systemic involvement. STUDY DESIGN AND METHODS Evaluation of two brothers carrying the McLeod phenotype with neurologic examination, immunohematology, RBC membrane protein Western blotting, analysis of XK DNA sequence and RNA levels, muscle histology including XK/Kell immunohistochemistry, cerebral magnetic resonance imaging (MRI), and quantified positron emission tomography (PET). RESULTS Immunohematology and Western blotting confirmed presence of the McLeod blood group phenotype. No acanthocytosis or other hematologic anomalies were found. XK gene sequence analysis revealed a missense mutation in exon 3 (E327K). WBC XK RNA levels were not decreased. There were no neuromuscular and CNS signs or symptoms. In addition, no subclinical involvement was discovered on the basis of normal muscle histology with a physiologic pattern of XK and Kell immunohistochemistry, normal cerebral MRI, and quantified PET. CONCLUSION Known disease-causing XK gene mutations comprised deletions, nonsense, or splice-site mutations predicting absent or truncated XK protein devoid of the Kell-protein binding site. Although the E327K missense mutation was associated with the immunohematologic characteristics of McLeod syndrome, the mutated XK protein seemed to be largely functional. These findings contribute to the understanding of the physiology of XK and Kell proteins, and the pathogenetic mechanisms of acanthocytosis, myopathy, and striatal neurodegeneration in McLeod syndrome.
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Affiliation(s)
- Hans H Jung
- Department of Neurology and the Institutes of Neuropathology, Nuclear Medicine, and Neuroradiology, University Hospital Zürich, Switzerland.
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Abstract
A 71-yr-old man was admitted for further evaluation and trans-sphenoidal surgery of a pituitary tumor. He complained of impotence and decreased libido over a period of about 40 yr. Thirty-eight yr ago he was treated for bilateral gynecomastia with galactorrhea. Endocrinological investigation at presentation revealed only mild hyperprolactinemia and hypogonadotropic hypogonadism. Pituitary magnetic resonance imaging (MRI) showed a tumor up to 2.5 cm in diameter with infiltration of the sphenoid sinus and right cavernous sinus. The tumor exhibited a heterogeneous hyperintense signal on T1-weighted images and hypointense signal on T2-weighted images. Standard trans-sphenoidal surgery was performed and a brownish mass was found inside the sella, which was removed. Histological examination of the mass revealed extensive spherical amyloid deposits with strongly positive immunohistochemical staining for prolactin. Therefore, a prolactinoma with extensive spherical amyloid deposition was diagnosed. Extensive spherical amyloid deposition is a rare finding in prolactin-secreting pituitary adenomas. So far, characteristic radiological findings by MRI have been described only twice. Due to characteristic MRI findings, the diagnosis of extensive intrasellar amyloid deposition can be entertained pre-operatively. Trans-sphenoidal surgical resection is essential to confirm the diagnosis histologically and because of the potential lack of tumor shrinkage under dopaminagonist therapy in this type of prolactinoma.
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Affiliation(s)
- P Wiesli
- Department of Internal Medicine, Division of Endocrinology and Diabetology, University Hospital of Zurich, Switzerland.
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Alkadhi H, Crelier GR, Imhof HG, Kollias SS. Somatomotor functional MRI in a large congenital arachnoid cyst. Neuroradiology 2003; 45:153-6. [PMID: 12684717 DOI: 10.1007/s00234-002-0929-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2002] [Accepted: 12/03/2002] [Indexed: 10/20/2022]
Abstract
The immature human brain, when damaged, is able to reorganise functionally. We performed functional MRI during eight different movements in a patient found incidentally to have an extensive, frontal, congenital arachnoid cyst, looking at which neural substrates contribute to motor control. Significant changes from the normal pattern of activation were seen in cortical and cerebellar areas which could not be accounted for by the space-occupying effect of the cyst alone. These findings in this asymptomatic patient with a congenital anomaly demonstrate an alternative organisation of the central motor system, with a preservation of neurological function.
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Affiliation(s)
- H Alkadhi
- Institute of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091, Zürich, Switzerland
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Abstract
Conflicting reports exist about the occurrence, reliability and localization of activation in the ipsilateral primary motor cortex (M1). We re-examined this issue with functional magnetic resonance imaging in 12 volunteers performing right hand, finger, wrist, elbow, foot and tongue movements in two separate sessions. Ipsilateral M1 activation was inconsistently and non-reliably present during all movements: in 54% of all hand, 50% elbow, 46% finger, 33% wrist, and in 17% of all foot experiments. When compared to contralateral M1, the volumes and maximum t-values were always smaller. The ipsilateral M1 body representation was somatotopically organized with coordinates similar to the contralateral M1. Finally, the presence of ipsilateral M1 activation depended on the global activation level in other motor-related areas, which was significantly increased, when ipsilateral M1 activation was detected.
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Affiliation(s)
- Hatem Alkadhi
- Institute of Neuroradiology, University Hospital Zurich, Zurich, Switzerland
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Curt A, Alkadhi H, Crelier GR, Boendermaker SH, Hepp-Reymond MC, Kollias SS. Changes of non-affected upper limb cortical representation in paraplegic patients as assessed by fMRI. Brain 2002; 125:2567-78. [PMID: 12390981 DOI: 10.1093/brain/awf250] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Peripheral and central nervous system lesions can induce reorganization within central somatosensory and motor body representations. We report changes in brain activation patterns during movements of non-affected body parts in paraplegic patients with spinal cord injury (SCI). Nine SCI patients and 12 healthy controls underwent blood oxygen level dependent signal functional MRI during sequential finger-to-thumb opposition, flexion and extension of wrist and of elbow, and horizontal movements of the tongue. Single subject and group analyses were performed, and the activation volumes, maximum t values and centres of gravity were calculated. The somatotopical upper limb and tongue representations in the contralateral primary motor cortex (M1) in the SCI patients were preserved without any shift of activation towards the deefferented and deafferented M1 foot area. During finger movements, however, the SCI patients showed an increased volume in M1 activation. Increased activation was also found in non-primary motor and parietal areas, as well as in the cerebellum during movements of the fingers, wrist and elbow, whereas no changes were present during tongue movements. These results document that, in paraplegic patients, the representation of the non-impaired upper limb muscles is modified, though without any topographical reorganization in M1. The extensive changes in primary and non-primary motor areas, and in subcortical regions demonstrate that even distant neuronal damage has impact upon the activation of the whole sensorimotor system.
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Affiliation(s)
- Armin Curt
- ParaCare, University Hospital Balgrist, Zürich, Switzerland.
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Alkadhi H, Crelier GR, Boendermaker SH, Golay X, Hepp-Reymond MC, Kollias SS. Reproducibility of primary motor cortex somatotopy under controlled conditions. AJNR Am J Neuroradiol 2002; 23:1524-32. [PMID: 12372742 PMCID: PMC7976799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
BACKGROUND AND PURPOSE The somatotopic organization of the contralateral primary motor cortex (M1) and its intra- and intersubject reproducibility has been the subject of many investigations and controversies. A potential explanation for a least some of the conflicting results could be the lack of movement control in the studies performed. The purpose of this study was to investigate these issues under controlled experimental conditions. METHODS Functional MR imaging was performed in 12 healthy volunteers performing hand, finger, wrist, elbow, foot, and tongue movements. Two experimental sessions were separated by 2 weeks. Controlled conditions were achieved by means of a custom-designed arm and hand manipulandum providing standardization of the movements within and across subjects. RESULTS The experiments revealed a clear large-scale somatotopy of the contralateral M1 with distinct subregions controlling the foot, arm, and tongue. Despite considerable overlap of the volumes, geometric centers of gravity (COGs) showed statistically significant differences in coordinates between the elbow, wrist, fingers, and hand. COGs showed a high degree of intra- and interindividual reproducibility, particularly for the upper limb movements, in contrast to the activation volumes that proved to be unreliable parameters, despite the controlled conditions. CONCLUSION These findings support the existence of a gross-scale somatotopic organization yet also demonstrate a clear, fine-scale somatotopy of the within-arm representations. Furthermore, they reveal high reproducibility of the COGs when standardized conditions are applied. This observation highlights the need for movement control to allow for intra- and intersubject comparison.
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Affiliation(s)
- Hatem Alkadhi
- Institute of Neuroradiology, University Hospital Zurich, Krauenklinikstrasse 10, CH-8091 Zurich, Switzerland
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