High Signal Regions in Normal White Matter Shown by Heavily T2-Weighted CSF Nulled IR Sequences

Hajnal, Joseph V.; B, De Coene; Pd, Lewis; Cj, Baudouin; Fm, Cowan; Jm, Pennock; Ir, Young; Gm, Bydder

doi:10.1097/00004728-199207000-00002

Cited by 148 publications

(83 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…There have been a few papers that have detected a small number of specific areas of WM heterogeneity using conventional MRI contrast at lower fields (27)(28)(29). However, none of these papers reported the widespread heterogeneity detected in the present work.…”

Section: Discussioncontrasting

confidence: 51%

High-field MRI of brain cortical substructure based on signal phase

Duyn

Gelderen

et al. 2007

Proc. Natl. Acad. Sci. U.S.A.

609

768

View full text Add to dashboard Cite

The ability to detect brain anatomy and pathophysiology with MRI is limited by the contrast-to-noise ratio (CNR), which depends on the contrast mechanism used and the spatial resolution. In this work, we show that in MRI of the human brain, large improvements in contrast to noise in high-resolution images are possible by exploiting the MRI signal phase at high magnetic field strength. Using gradient-echo MRI at 7.0 tesla and a multichannel detector, a nominal voxel size of 0.24 ؋ 0.24 ؋ 1.0 mm 3 (58 nl) was achieved. At this resolution, a strong phase contrast was observed both between as well as within gray matter (GM) and white matter (WM). In gradient-echo phase images obtained on normal volunteers at this high resolution, the CNR between GM and WM ranged from 3:1 to 20:1 over the cortex. This CNR is an almost 10-fold improvement over conventional MRI techniques that do not use image phase, and it is an Ϸ100-fold improvement when including the gains in resolution from high-field and multichannel detection. Within WM, phase contrast appeared to be associated with the major fiber bundles, whereas contrast within GM was suggestive of the underlying layer structure. The observed phase contrast is attributed to local variations in magnetic susceptibility, which, at least in part, appeared to originate from iron stores. The ability to detect cortical substructure from MRI phase contrast at high field is expected to greatly enhance the study of human brain anatomy in vivo.anatomy ͉ contrast mechanism ͉ cortex

show abstract

Section: Discussioncontrasting

confidence: 51%

High-field MRI of brain cortical substructure based on signal phase

Duyn

Gelderen

et al. 2007

Proc. Natl. Acad. Sci. U.S.A.

609

768

View full text Add to dashboard Cite

show abstract

“…22 A third fluid-attenuated inversion recovery (FLAIR) scan sequence was used to detect lesions in the central white matter and lesions next to CSF in the cortex and periventricular regions. 23 MRI data were also spatially transformed into stereotactic space, segmented, and analyzed voxel by voxel to identify any differences in gray matter density. 24 Statistical parametric mapping (SPM) was used to identify overall differences in gray matter density between groups.…”

Section: Mri Scans and Analysismentioning

confidence: 99%

Memory Impairment in Out-of-Hospital Cardiac Arrest Survivors Is Associated With Global Reduction in Brain Volume, Not Focal Hippocampal Injury

Grubb

Fox

Smith

et al. 2000

Stroke

110

View full text Add to dashboard Cite

Background and Purpose-More than 30% of out-of-hospital cardiac arrest (OHCA) survivors suffer significant memory impairment. The hippocampus may be vulnerable to hypoxic injury during cardiac arrest. The purpose of this study was to determine whether selective hippocampal injury is the substrate for this memory impairment. Methods-Seventeen OHCA survivors and 12 patients with uncomplicated myocardial infarction were studied. OHCA survivors were divided into those with impaired and intact memory.

show abstract

Section: ------------------------------------------------------------unclassified

“…Normal kişilerde ve kortikospinal traktı tutan primer lateral skleroz başta olmak üzere diğer dejeneratif hastalıklarda da tanımlanmıştır (2,(8)(9)(10). Wallerian dejenerasyona neden olan patolojiler ALS'yi radyolojik olarak taklit edebilirler (2,5,10). Radyasyon hasarı, arsenik, talyum gibi toksik ajanlar, vitamin ve enzim defektleri, HIV, sifiliz, bruselloz, Creutzfeldt-Jacob gibi enfeksiyöz hastalıklar, motor ve monoklonal gammopatiler ile ilişkili nöropatiler, Hodgkin ve non-Hodgkin lenfomalar, vasküler hastalıklar, osteosklerotik myeloma ve spondilitik myopati de klinik olarak ALS'yi taklit edebilir (9).…”

Section: ------------------------------------------------------------unclassified

Olgu Sunumu: Amyotrofik Lateral Sklerozda Kranial MRG Bulguları

Evren;ERDEN¹

2002

Ankara Üniversitesi Tıp Fakültesi Mecmuası

View full text Add to dashboard Cite

Amyotrofik lateral skleroz (ALS), üst ve alt motor nöron dejenerasyonu ile karakterize ilerleyici, ölümle sonuçlanan, nörodejeneratif bir hastalıktır (1,2). ALS motor nöron hastalıklarının en sık izlenen, en çok tanınan tipi olup erişkin çağda, sporadik olarak ortaya çıkmaktadır ve %5-10 oranında ailesel formu da tanımlanmıştır (2). Tanı klinik ve elektrofizyolojik bulgular ile konmaktadır. Hastalı-ğın tanısının konmasını sağlayacak kesin bir tanı-sal test yoktur (3). Kranial ve spinal MR gibi görün-tüleme yöntemlerinin asıl önemi ALS'yi taklit eden patolojilerin ortaya konmasını sağlamalarıdır. Ancak bazı ALS hastalarında MR görüntüleme ile motor korteks, spinal kord, kortikobulber ve kortikospinal traktlarda T1 ve T2 ağırlıklı görüntülerde anomaliler gösterilmiştir. Tanımlanan anomalilerin ALS tanısı için spesifik olmasa da hastalığın tanı ve takibinde önemi olduğu düşünülmektedir (2). Yazımızda ALS'li bir olguya ait kranial MR gö-rüntüleme bulguları sunulmuştur.O OL LG GU U B Bİ İL LD Dİ İR Rİ İS Sİ İ 49 yaşında, erkek hasta konuşma ve yutma güçlüğü şikayeti ile nöroloji bölümüne başvurdu. Şikayetlerinin 7 ay önce başladığı öğrenildi. Öz-geçmişinde günde 1 paket sigara içmesi dışında bir özellik yoktu ve ailede benzer bir hastalık öy-küsü bulunmamaktaydı. Yapılan nörolojik muaye-ANKARA ÜNİVERSİTESİ TIP FAKÜLTESİ MECMUASI Cilt 55, Sayı 3, 2002 231-236

show abstract

High Signal Regions in Normal White Matter Shown by Heavily T2-Weighted CSF Nulled IR Sequences

Cited by 148 publications

References 0 publications

High-field MRI of brain cortical substructure based on signal phase

High-field MRI of brain cortical substructure based on signal phase

Memory Impairment in Out-of-Hospital Cardiac Arrest Survivors Is Associated With Global Reduction in Brain Volume, Not Focal Hippocampal Injury

Olgu Sunumu: Amyotrofik Lateral Sklerozda Kranial MRG Bulguları

Contact Info

Product

Resources

About