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Non-Synonyms (Similar-Sounding)
Published in Terence R. Anthoney, Neuroanatomy and the Neurologic Exam, 2017
External capsule (B&K, p. 206): Though the term “capsule” is general and can be used with reference to specific microscopic (e.g., capsules around neuronal cell bodies in spinal ganglia: C&S, p. 70) or macroscopic (e.g., capsule of the red nucleus: C&S, p. 433) structures, the “internal capsule,” “external capsule,” and “extreme capsule” (see below) are unique structures in the subcortical cerebrum, which surround various bodies of subcortical gray matter. The external capsule is external to the lentiform nucleus, but internal to the claustrum. When unqualified, “capsule” or “capsular” usually refers neuroanatomically to the internal capsule, especially in clinical contexts.
Neuroimaging
Published in Sarah McWilliams, Practical Radiological Anatomy, 2011
These areas represent the area inside the sylvian fissure. The claustrum is also called the external capsule, and its territory is supplied by the middle cerebral artery. The syl-vian fissures are usually symmetrical and asymmetry or loss of visualization of the fissure may be the only clue to a subarachnoid haemorrhage or pathology (Fig. 1.21).
ENTRIES A–Z
Published in Philip Winn, Dictionary of Biological Psychology, 2003
The EXTERNAL CAPSULE, EXTREME CAPSULE and INTERNAL CAPSULE are all fibre pathways that connect the CEREBRAL CORTEX with subcortical structures. The internal capsule is the best known. It can be divided into the anterior limb, genu (the middle portion, which has a bend—genu is Latin for knee) and the posterior limb. It carries almost all connections between the THALAMUS and both the STRIATUM and cortex, as well as fibres running from the cortex to the MIDBRAIN and BRAINSTEM. Ascending fibres in the DORSAL COLUMN—MEDIAL LEMNISCAL SYSTEM canying information from the body travel to the cortex via the internal capsule. The external and extreme capsules also carry information between the cortex and subcortical sites. The three capsules are named by their positions. The internal capsule in the human brain runs between the CAUDATE NUCLEUS and PUTAMEN, closer to the MIDLINE of the brain than either the external or extreme capsules. The external capsule runs on the outside of the putamen, but below the CLAUSTRUM, The extreme capsule lies over the claustrum, immediately below the cortex—it is the most extremely lateral of the capsules.
Genetic diseases mimicking multiple sclerosis
Published in Postgraduate Medicine, 2021
Chueh Lin Hsu, Piotr Iwanowski, Chueh Hsuan Hsu, Wojciech Kozubski
Numerous lacunar infarctions in the basal ganglia and white matter hyperintensities are seen under brain MRI [71]. The lesions are mostly located in the periventricular and deep white matter. Subcortical U-fibers involvement is less common. Subsequently, the extension of lesions into the thalamus, brainstem, and cerebellum have been documented [71,72]. Characteristic advanced disease stage MRI findings include infratentorial and external capsule lesions. Atrophies are found in different locations in the brain as the disease progresses. In the early stage, atrophy is located mainly in the central cortex and brainstem; frontal and temporal cortex atrophy is remarkable in the middle stage; cerebellar atrophy predominates in the advanced stage [72]. Spinal disk herniations and spondylosis deformans around lower thoracic and /or upper lumbar regions under MRI are shown in CARASIL patients present with low back pain [70]. OCB analysis is mostly negative [65,66,68,69].
3.0 Tesla MRI scanner evaluation of supratentorial major white matter tracts and central core anatomical structures of postmortem human brain hemispheres fixed by Klingler method
Published in British Journal of Neurosurgery, 2021
Murat Atar, Ceren Kizmazoglu, Ismail Kaya, Nevin Aydin, Ufuk Corumlu, Gulden Sozer, Hasan Emre Aydin, Orhan Kalemci, Nuri Karabay, Nurullah Yuceer
Figure 3 shows the external capsule just below the claustrum can be clearly distinguished. The external capsule contains three different fiber systems, which are uncinate fascicle, inferior fronto-occipital fascicle, and the claustro-cortical fibers. The uncinate fascicle, indicated by the red dots, is shown in the figure, and its lines can be clearly distinguished. In addition, the connection of the anterior commissure to both hemispheres, indicated with the blue dots, and its subsequent orientation to the temporal region are noteworthy. In addition to this a comparison of the T2 axial 3.0 Tesla MRI scanner image with the previous image obtained from a healthy volunteer reveals that the image obtained from the post-mortem human hemisphere fixed using the Klinger method is highly superior. Anatomical structures in the central cores and white matter tracts can be clearly seen.
The impact of phonological versus semantic repetition training on generalisation in chronic stroke aphasia reflects differences in dorsal pathway connectivity
Published in Neuropsychological Rehabilitation, 2018
Rachel Holland, Sasha L. Johns, Anna M. Woollams
Inspection of the integrity of the ventral pathway (Figure 4, panels D and E) showed no evidence of damage to the uncinate, inferior longitudinal or inferior occipital segments. However, these templates do not consider the external capsule, a component of the ventral pathway (Bajada, Lambon Ralph, & Cloutman, 2015; Parker et al., 2003). Additional inspection of the ACMs against the Johns Hopkins University template as implemented in MRIcroN (Rorden, Karnath, & Bonilha, 2007) showed very minor damage to the external capsule for DM. For JS, more pronounced damage to the external capsule was apparent, (panel G of Figure 4). In both cases, the damage to the ventral pathway was much less than that for the dorsal pathway. Moreover, the degree of external capsule damage would lead us to expect greater potential benefits from semantic therapy for DM than JS, where in fact the opposite pattern was observed.