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High resolution magnetic resonance imaging of the limbic system
CNS -- GENERAL MRI
OF
Donald Ohio
THE
VASCULAR
W Chakeres
State
STRUCTURES
MD,
Univerity
ABOUT
THE
Vicky
Marts
MD.
College
of
Medicine
HRAINSTEM
Kenneth
Weiss
,Columbus,
AND
CEREBELLUM
MD,
James
Mosure
MD
Ohlo
High resolution MRI can visualize many small blood vessels about the brainstem and cerebellum with much greater frequency than CT. Using a General Electric Signa MRI scanner we were able to routinely identify most of the small vascular structures commonly seen on standard clinical cerebral All of the images were made with a General Electric 1.5 tesla angiogt-aphy. We review the MRI appearance of the following vessels as seen Signa system. (spin echo and partlal saturation techniques on varying pulse sequence images msec,TE's 25-160) and sectlon planes utilizing TR’s ranging form 200-2500 (axial,sagittal,coronal): basilar, vertebral, superior cerebellar, posterior and the precentral posterior communicating, and chorodlal arteries; cerebral, basal veins of Rosenthal, cerebellrr lateral mesencephalic, cerebellar, Direct comparison to standard angiograms on the same patients vet-mlan veins. We discuss the variable elgnal was avaiable in a large number of cases. intensities visible on images of the same vessel related to flow dynamics. The clinical significance of understanding the normal anatomy of these venous arteriovenous malformations (AVM) structures includes: mass localization, and separtlon of venous from arterial evaluation, occlusive vascul at- disease, One major limitation is the absence of a vascular blush a5 IS structures. IF MRI can accurately visualize the small seen in standard agiography. then it IS conceivable that MRI can have a vessels of the posterior fossa, major impact on angiography.
HIGH Donald Ohio
RESOLUTION Chakeres State
MFIGNETIC
RESONANCE
IMAGING
MD,
Flynn
and
University
Eric
College
MD, of
OF
Kenneth
Medicine
THE
LIMRIC
Weiss
, Columbus
SYSTEM
MD , Ohio
The limbic system is composed of a ring of multiple gray and white matter structures that encircle the brainstem. The limbic system 1s felt to be important in disorders of smell, memory, behavior, emotion, and movement. MRI can visualize many of the individual structures forming the limbic system with much greater accuracy than CT. We describe the normal and pathologic anatomy of the hippocampus, dentate gyrus, columns of the fornix, mammillary bodies, stria terminalis, amygdala, uncus, cingulate gyrus , cingulum , and anterior commissure. It is believed that the limbic system acts as an interface between primitive homeostatic functions of the brainstem hypothalamus and the cerebral cortex. CT has limited ability to identify abnormalities of the limbic system. Many of the structures simply cannot be consisitently visualized. The limbic system is one anatomic area where MRI has the potential to significantly expand the understanding of pathology involving this complex group of structures. Comparison of high resolution MRI images of normal and pathologic patients , and fixed cadaver brains to anatomic sections of normal brains sectioned in the same planes were made. All of the images were made with a General Electric Signa 1.5 Tesla imager. Multiple axial, sagittal, and coronal thin section (3-5mm) high resolution (G-20 cm field of view 256x256 pixel matrix) images using multiple spin echo techniques were made. The appearance and intensities of the components of the limbic system on multiple section planes and pulse sequences are reviewed. Examples of pathologic distortion of the limbic system are shown, including: mass lesions, congenital abnormalities, brain atrophy, and hydrocephalus.
159
OF
Donald Ohio
THE
VASCULAR
W Chakeres
State
STRUCTURES
MD,
Univerity
ABOUT
THE
Vicky
Marts
MD.
College
of
Medicine
HRAINSTEM
Kenneth
Weiss
,Columbus,
AND
CEREBELLUM
MD,
James
Mosure
MD
Ohlo
High resolution MRI can visualize many small blood vessels about the brainstem and cerebellum with much greater frequency than CT. Using a General Electric Signa MRI scanner we were able to routinely identify most of the small vascular structures commonly seen on standard clinical cerebral All of the images were made with a General Electric 1.5 tesla angiogt-aphy. We review the MRI appearance of the following vessels as seen Signa system. (spin echo and partlal saturation techniques on varying pulse sequence images msec,TE's 25-160) and sectlon planes utilizing TR’s ranging form 200-2500 (axial,sagittal,coronal): basilar, vertebral, superior cerebellar, posterior and the precentral posterior communicating, and chorodlal arteries; cerebral, basal veins of Rosenthal, cerebellrr lateral mesencephalic, cerebellar, Direct comparison to standard angiograms on the same patients vet-mlan veins. We discuss the variable elgnal was avaiable in a large number of cases. intensities visible on images of the same vessel related to flow dynamics. The clinical significance of understanding the normal anatomy of these venous arteriovenous malformations (AVM) structures includes: mass localization, and separtlon of venous from arterial evaluation, occlusive vascul at- disease, One major limitation is the absence of a vascular blush a5 IS structures. IF MRI can accurately visualize the small seen in standard agiography. then it IS conceivable that MRI can have a vessels of the posterior fossa, major impact on angiography.
HIGH Donald Ohio
RESOLUTION Chakeres State
MFIGNETIC
RESONANCE
IMAGING
MD,
Flynn
and
University
Eric
College
MD, of
OF
Kenneth
Medicine
THE
LIMRIC
Weiss
, Columbus
SYSTEM
MD , Ohio
The limbic system is composed of a ring of multiple gray and white matter structures that encircle the brainstem. The limbic system 1s felt to be important in disorders of smell, memory, behavior, emotion, and movement. MRI can visualize many of the individual structures forming the limbic system with much greater accuracy than CT. We describe the normal and pathologic anatomy of the hippocampus, dentate gyrus, columns of the fornix, mammillary bodies, stria terminalis, amygdala, uncus, cingulate gyrus , cingulum , and anterior commissure. It is believed that the limbic system acts as an interface between primitive homeostatic functions of the brainstem hypothalamus and the cerebral cortex. CT has limited ability to identify abnormalities of the limbic system. Many of the structures simply cannot be consisitently visualized. The limbic system is one anatomic area where MRI has the potential to significantly expand the understanding of pathology involving this complex group of structures. Comparison of high resolution MRI images of normal and pathologic patients , and fixed cadaver brains to anatomic sections of normal brains sectioned in the same planes were made. All of the images were made with a General Electric Signa 1.5 Tesla imager. Multiple axial, sagittal, and coronal thin section (3-5mm) high resolution (G-20 cm field of view 256x256 pixel matrix) images using multiple spin echo techniques were made. The appearance and intensities of the components of the limbic system on multiple section planes and pulse sequences are reviewed. Examples of pathologic distortion of the limbic system are shown, including: mass lesions, congenital abnormalities, brain atrophy, and hydrocephalus.
159