DTI-based tractography of the arcuate fasciculus in patients with polymicrogyria and language disorders

Andrade, Celi Santos; Figueiredo, Kenya G.; Valeriano, Cassia; Mendoza, Melanie; Valente, Kette D.; Otaduy, Maria Concepción García; Leite, Cláudia C.

doi:10.1016/j.ejrad.2015.07.014

Cited by 13 publications

(9 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, four out of nine PHTS cases in our study accompanied polymicrogyria around the sylvian fissure. Prior DTI studies in polymicrogyria showed decreased FA and increased ADC through long association pathways and the CP (Andrade et al, ; Im, Paldino, Poduri, Sporns, & Grant, ). The presence of polymicrogyria in our PHTS cases may have contributed to the increased ADC in the left ILF.…”

Section: Discussionmentioning

confidence: 95%

Brain morphological analysis in PTEN hamartoma tumor syndrome

Shiohama

Levman

Vasung

et al. 2020

American J of Med Genetics Pt A

View full text Add to dashboard Cite

PTEN hamartoma tumor syndrome (PHTS) is a spectrum of hereditary cancer syndromes caused by germline mutations in PTEN. PHTS is of high interest, because of its high rate of neurological comorbidities including macrocephaly, autism spectrum disorder, and intellectual dysfunction. Since detailed brain morphology and connectivity of PHTS remain unclear, we quantitatively evaluated brain magnetic resonance imaging (MRI) in PHTS. Sixteen structural T1-weighted and 9 diffusion-weighted MR images from 12 PHTS patients and neurotypical controls were used for structural and high-angular resolution diffusion MRI (HARDI) tractography analyses. Megacorpus callosum was observed in 75%, polymicrogyria in 33%, periventricular white matter lesions in 83%, and heterotopia in 17% of the PHTS participants. While gyrification index and hemispheric cortical thickness showed no significant differences between the two groups, significantly increased global and regional brain volumes, and regionally thicker cortices in PHTS participants were observed. HARDI tractography showed increased volume and length of callosal pathways, increased volume of the arcuate fasciculi (AF), and increased length of the bilateral inferior longitudinal fasciculi (ILF), bilateral inferior fronto-occipital fasciculi (IFOF), and bilateral uncinate fasciculus. A decrease in fractional anisotropy and an increased in apparent diffusion coefficient values of the AF, left ILF, and left IFOF in PHTS. K E Y W O R D SHARDI, mega corpus callosum, megalencephaly, PTEN hamartoma tumor syndrome, structural brain MRI

show abstract

Section: Discussionmentioning

confidence: 95%

Brain morphological analysis in PTEN hamartoma tumor syndrome

Shiohama

Levman

Vasung

et al. 2020

American J of Med Genetics Pt A

View full text Add to dashboard Cite

show abstract

“…36,37 Abnormal SLF morphology was frequently identified in our PMG cohort, consistent with findings from other studies. 13,15,17 In our peri-Sylvian PMG cohort, the severity of SLF abnormalities (ie, from normal to irregular to absent) was found to be associated with the severity and extent of MCD. Related volumetric analysis (On-line Fig 4) highlighted that the volume of malformed cortices in the patients with peri-Sylvian PMG with absent or irregular SLF was significantly higher than that in patients with normal SLFs.…”

Section: Discussionmentioning

confidence: 62%

“…and S.M.) and scored in consensus using a modified version of a semiquantitative scoring system previously used to grade WMT abnormalities in other MCDs: 13,28 • Grade I (normal): WMTs with similar size and geometry compared with the healthy controls • Grade IIA (irregular): WMTs characterized by at least 1 of the following features: reduced size, displaced fibers, or distorted geometry • Grade IIB (thick): WMTs with increased size compared with those in the healthy controls • Grade III (absent): failed tractography reconstruction and no recognizable WMTs on the DEC maps…”

Section: Data Analysis: a Semiquantitative Wm Tract Analysismentioning

confidence: 99%

Characterizing White Matter Tract Organization in Polymicrogyria and Lissencephaly: A Multifiber Diffusion MRI Modeling and Tractography Study

Arrigoni

Peruzzo

Mandelstam

et al. 2020

AJNR Am J Neuroradiol

View full text Add to dashboard Cite

BACKGROUND AND PURPOSE: Polymicrogyria and lissencephaly may be associated with abnormal organization of the undelying white matter tracts that have been rarely investigated so far. Our aim was to characterize white matter tract organization in polymicrogyria and lissencephaly using constrained spherical deconvolution, a multifiber diffusion MR imaging modeling technique for white matter tractography reconstruction. MATERIALS AND METHODS:We retrospectively reviewed 50 patients (mean age, 8.3 6 5.4 years; range, 1.4-21.2 years; 27 males) with different polymicrogyria (n ¼ 42) and lissencephaly (n ¼ 8) subtypes. The fiber direction-encoded color maps and 6 different white matter tracts reconstructed from each patient were visually compared with corresponding images reconstructed from 7 agematched, healthy control WM templates. Each white matter tract was assessed by 2 experienced pediatric neuroradiologists and scored in consensus on the basis of the severity of the structural abnormality, ranging from the white matter tracts being absent to thickened. The results were summarized by different polymicrogyria and lissencephaly subgroups.RESULTS: More abnormal-appearing white matter tracts were identified in patients with lissencephaly compared with those with polymicrogyria (79.2% versus 37.3%). In lissencephaly, structural abnormalities were identified in all studied white matter tracts. In polymicrogyria, the more frequently affected white matter tracts were the cingulum, superior longitudinal fasciculus, inferior longitudinal fasciculus, and optic radiation-posterior corona radiata. The severity of superior longitudinal fasciculus and cingulum abnormalities was associated with the polymicrogyria distribution and extent. A thickened superior fronto-occipital fasciculus was demonstrated in 3 patients. CONCLUSIONS:We demonstrated a range of white matter tract structural abnormalities in patients with polymicrogyria and lissencephaly. The patterns of white matter tract involvement are related to polymicrogyria and lissencephaly subgroups, distribution, and, possibly, their underlying etiologies. ABBREVIATIONS: CG ¼ cingulum; CMV ¼ cytomegalovirus; CSD ¼ constrained spherical deconvolution; DEC ¼ direction-encoded color; dMRI ¼ diffusion MRI; FOD ¼ fiber orientation distribution; HARDI ¼ high angular resolution diffusion imaging; IFOF ¼ inferior fronto-occipital fasciculus; ILF ¼ inferior longitudinal fasciculus; LIS ¼ lissencephaly; MCD ¼ malformation of cortical development; OR-PCR ¼ optic radiation-posterior corona radiata; PMG ¼ polymicrogyria; SBH ¼ subcortical band heterotopia; SFOF ¼ superior fronto-occipital fasciculus/Muratoff bundle; SLF ¼ superior longitudinal fasciculus; WMT ¼ white matter tract

show abstract

“…Moreover, fiber dissection is operator‐dependent and applicable only postmortem. Magnetic resonance‐based diffusion imaging is applicable to living subjects but is susceptible to noise, artifacts, and operator‐related variations (Andrade et al, 2015; Maldonado et al, 2012; Martino, De Witt Hamer, et al, 2013). Fiber kissing or crossing are sources of difficulty in both methods.…”

Section: Discussionmentioning

confidence: 99%

“…Among the methods for assessing superior longitudinal fasciculus (SLF) and AF morphology, magnetic resonance‐based diffusion imaging is noteworthy because of its use in vivo and clinical application in different domains such as stroke (Kim & Jang, 2013; Kristo et al, 2013), cognitive disorders (Andrade et al, 2015; Jeong et al, 2011; Kristo et al, 2013; Nagae et al, 2012; Paldino et al, 2016), and brain tumors (Kristo et al, 2013; Mormina et al, 2015). The importance of this white matter structure for the daily practice of neuroradiology has been progressively acknowledged during the last decade, as has been the case in neurology, neurosurgery, and fundamental neurosciences.…”

Section: Introductionmentioning

confidence: 99%

What's your name again? A review of the superior longitudinal and arcuate fasciculus evolving nomenclature

2021

View full text Add to dashboard Cite

Studies of the superior longitudinal fasciculus (SLF) have multiplied in recent decades owing to methodological advances, but the absence of a convention for nomenclature remains a source of confusion. Here, we have reviewed existing nomenclatures in the context of the research studies that generated them and we have identified their agreements and disagreements. A literature search was conducted using PubMed/MEDLINE, Web‐of‐Science, Embase, and a review of seminal publications, without restrictions regarding publication date. Our search revealed that diffusion imaging, autoradiography, and fiber dissection have been the main methods contributing to tract designation. The first two have been particularly influential in systematizing the horizontal elements distant from the lateral sulcus. Twelve approaches to naming were identified, eight of them differing considerably from each other. The terms SLF and arcuate fasciculus (AF) were often used as synonyms until the second half of the 20th century. During the last 15 years, this has ceased to be the case in a growing number of publications. The term AF has been used to refer to the assembly of three different segments, or exclusively to long frontotemporal fibers. Similarly, the term SLF has been employed to denote the whole superior longitudinal associative system, or only the horizontal frontoparietal parts. As only partial correspondence can be identified among the available nomenclatures, and in the absence of an official designation of all anatomical structures that can be encountered in clinical practice, a high level of vigilance regarding the effectiveness of every oral or written act of communication is mandatory.

show abstract

DTI-based tractography of the arcuate fasciculus in patients with polymicrogyria and language disorders

Cited by 13 publications

References 28 publications

Brain morphological analysis in PTEN hamartoma tumor syndrome

Brain morphological analysis in PTEN hamartoma tumor syndrome

Characterizing White Matter Tract Organization in Polymicrogyria and Lissencephaly: A Multifiber Diffusion MRI Modeling and Tractography Study

What's your name again? A review of the superior longitudinal and arcuate fasciculus evolving nomenclature

Contact Info

Product

Resources

About