Three-Dimensional Fractal Analysis of the White Matter Surface from Magnetic Resonance Images of the Human Brain

Abstract OBJECTIVE: To demonstrate that magnetic resonance diffusion tensor imaging (DTI) with three-dimensional (3-D) fiber tractography can visualize traumatic axonal shearing injury that results in posterior callosal disconnection syndrome. METHODS: A 22-year-old man underwent serial magnetic resonance imaging 3 days and 12 weeks after blunt head injury. The magnetic resonance images included whole-brain DTI acquired with a single-shot spin echo echoplanar sequence. 3-D DTI fiber tractography of the splenium of the corpus callosum was performed. Quantitative DTI parameters, including apparent diffusion coefficient and fractional anisotropy, from the site of splenial injury were compared with those of a normal adult male volunteer. RESULTS: Conventional magnetic resonance images revealed findings of diffuse axonal injury, including a lesion at the midline of the splenium of the corpus callosum. DTI performed 3 days posttrauma revealed that the splenial lesion had reduced apparent diffusion coefficient and fractional anisotropy, reflecting a large decrease in the magnitude of diffusion parallel to the white matter fibers, which had partially recovered as revealed by follow-up DTI 12 weeks postinjury. 3-D tractography revealed an interruption of the white matter fibers in the posteroinferior aspect of the splenium that correlated with the patient's left hemialexia, a functional deficit caused by disconnection of the right visual cortex from the language centers of the dominant left hemisphere. CONCLUSION: DTI with 3-D fiber tractography can visualize acute axonal shearing injury, which may have prognostic value for the cognitive and neurological sequelae of traumatic brain injury.

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Maturation of white matter in the human brain: a review of magnetic resonance studies

Brain Research Bulletin ◽

10.1016/s0361-9230(00)00434-2 ◽

2001 ◽

Vol 54 (3) ◽

pp. 255-266 ◽

Cited By ~ 575

Author(s):

T Paus ◽

D.L Collins ◽

A.C Evans ◽

G Leonard ◽

B Pike ◽

...

Keyword(s):

White Matter ◽

Magnetic Resonance ◽

Human Brain ◽

Magnetic Resonance Studies

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White matter fiber tracts of the human brain: Three-dimensional mapping at microscopic resolution, topography and intersubject variability

NeuroImage ◽

10.1016/j.neuroimage.2005.08.040 ◽

2006 ◽

Vol 29 (4) ◽

pp. 1092-1105 ◽

Cited By ~ 276

Author(s):

Uli Bürgel ◽

Katrin Amunts ◽

Lars Hoemke ◽

Hartmut Mohlberg ◽

Joachim M. Gilsbach ◽

...

Keyword(s):

White Matter ◽

Human Brain ◽

Three Dimensional ◽

Intersubject Variability ◽

Fiber Tracts ◽

Three Dimensional Mapping ◽

White Matter Fiber Tracts ◽

Dimensional Mapping

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The Safety of Operating on Breasts With a History of Prior Reduction Mammoplasty: Dynamic Magnetic Resonance Imaging Analysis of Angiogenesis

Aesthetic Surgery Journal ◽

10.1093/asj/sjab318 ◽

2021 ◽

Author(s):

Joseph Kyu-hyung Park ◽

Seokwon Park ◽

Chan Yeong Heo ◽

Jae Hoon Jeong ◽

Bola Yun ◽

...

Keyword(s):

Magnetic Resonance ◽

Three Dimensional ◽

Venous Drainage ◽

Reduction Mammoplasty ◽

Magnetic Resonance Images ◽

Areolar Complex ◽

Internal Mammary ◽

Initial Procedure ◽

Nipple Sparing Mastectomy ◽

Nipple Sparing

Abstract Background Vascularity of the nipple-areolar complex (NAC) is altered after reduction mammoplasty, which increases complications risks after repeat reduction or nipple-sparing mastectomy. Objectives To evaluate angiogenesis of the NAC via serial analysis of breast magnetic resonance images (MRIs). Methods Breast MRIs after reduction mammoplasty were analyzed for 35 patients (39 breasts) using three-dimensional reconstructions of maximal intensity projection images. All veins terminating at the NAC were classified as internal mammary, anterior intercostal, or lateral thoracic in origin. The vein with the largest diameter was considered the dominant vein. Images were classified based on the time since reduction: <6 months, 6-12 months, 12-24 months, >2 years. Results The average number of veins increased over time: 1.17 (<6 months), 1.56 (6–12 months), 1.64 (12–24 months), 1.73 (>2 years). Within 6 months, the pedicle was the only vein. Veins from other sources began to appear at 6–12 months. In most patients, at least two veins were available after 1 year. After 1 year, the internal mammary vein was the most common dominant vein regardless of the pedicle used. Conclusions In the initial 6 months after reduction mammoplasty, the pedicle is the only source of venous drainage; however, additional sources are available after 1 year. The internal thoracic vein was the dominant in most patients. Thus, repeat reduction mammoplasty or nipple-sparing mastectomy should be performed ≥1 year following the initial procedure. After 1 year, the superior or superomedial pedicle may represent the safest option when the previous pedicle is unknown.

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Differentiation of Glucose Transport in Human Brain Gray and White Matter

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200105000-00002 ◽

2001 ◽

Vol 21 (5) ◽

pp. 483-492 ◽

Cited By ~ 70

Author(s):

Robin A. de Graaf ◽

Jullie W. Pan ◽

Frank Telang ◽

Jing-Huei Lee ◽

Peter Brown ◽

...

Keyword(s):

Nuclear Magnetic Resonance ◽

Steady State ◽

White Matter ◽

Magnetic Resonance ◽

Human Brain ◽

Glucose Transport ◽

Gray Matter ◽

Transport Model ◽

Transport Activity ◽

Brain Glucose

Localized 1H nuclear magnetic resonance spectroscopy has been applied to determine human brain gray matter and white matter glucose transport kinetics by measuring the steady-state glucose concentration under normoglycemia and two levels of hyperglycemia. Nuclear magnetic resonance spectroscopic measurements were simultaneously performed on three 12-mL volumes, containing predominantly gray or white matter. The exact volume compositions were determined from quantitative T1 relaxation magnetic resonance images. The absolute brain glucose concentration as a function of the plasma glucose level was fitted with two kinetic transport models, based on standard (irreversible) or reversible Michaelis-Menten kinetics. The steady-state brain glucose levels were similar for cerebral gray and white matter, although the white matter levels were consistently 15% to 20% higher. The ratio of the maximum glucose transport rate, Vmax, to the cerebral metabolic utilization rate of glucose, CMRGlc, was 3.2 ± 0.10 and 3.9 ± 0.15 for gray matter and white matter using the standard transport model and 1.8 ± 0.10 and 2.2 ± 0.12 for gray matter and white matter using the reversible transport model. The Michaelis-Menten constant Km was 6.2 ± 0.85 and 7.3 ± 1.1 mmol/L for gray matter and white matter in the standard model and 1.1 ± 0.66 and 1.7 ± 0.88 mmol/L in the reversible model. Taking into account the threefold lower rate of CMRGlc in white matter, this finding suggests that blood–brain barrier glucose transport activity is lower by a similar amount in white matter. The regulation of glucose transport activity at the blood–brain barrier may be an important mechanism for maintaining glucose homeostasis throughout the cerebral cortex.

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