File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Functional MRI of postnatal visual development in normal and hypoxic-ischemic-injured superior colliculi

TitleFunctional MRI of postnatal visual development in normal and hypoxic-ischemic-injured superior colliculi
Authors
KeywordsDeveloping brain
Diffusion tensor imaging
Functional MRI
Neonatal hypoxic-ischemic injury
Superior colliculus
Vision
Issue Date2010
PublisherAcademic Press. The Journal's web site is located at http://www.elsevier.com/locate/ynimg
Citation
Neuroimage, 2010, v. 49 n. 3, p. 2013-2020 How to Cite?
AbstractThe superior colliculus (SC) is a laminated subcortical structure in the mammalian midbrain, whose superficial layers receive visual information from the retina and the visual cortex. To date, its functional organization and development in the visual system remain largely unknown. This study employed blood oxygenation level-dependent (BOLD) functional MRI to evaluate the visual responses of the SC in normally developing and severe neonatal hypoxic-ischemic (HI)-injured rat brains from the time of eyelid opening to adulthood. MRI was performed to the normal animals (n = 7) at postnatal days (P) 14, 21, 28 and 60. In the HI-injured group (n = 7), the ipsilesional primary and secondary visual cortices were completely damaged after unilateral ligation of the left common carotid artery at P7 followed by hypoxia for 2 h, and MRI was performed at P60. Upon unilateral flash illumination, the normal contralateral SC underwent a systematic increase in BOLD signal amplitude with age especially after the third postnatal week. However, no significant difference in BOLD signal increase was found between P14 and P21. These findings implied the presence of neurovascular coupling at the time of eyelid opening, and the progressive development of hemodynamic regulation in the subcortical visual system. In the HI-injured group at P60, the BOLD signal increases in both SC remained at the same level as the normal group at P28 though they were significantly lower than the normal group at P60. These observations suggested the residual visual functions on both sides of the subcortical brain, despite the damages to the entire ipsilesional visual cortex. The results of this study constitute important evidence on the progressive maturation of visual functions and hemodynamic responses in the normal subcortical brain, and its functional plasticity upon neonatal HI injury. © 2009 Elsevier Inc. All rights reserved.
Persistent Identifierhttp://hdl.handle.net/10722/155548
ISSN
2015 Impact Factor: 5.463
2015 SCImago Journal Rankings: 4.464
ISI Accession Number ID
Funding AgencyGrant Number
Hong Kong Research Grant CouncilGRF HKU 7793/08M
Funding Information:

The authors Would like to thank Dr. Ke-xia Cai, MS. Shu-juan Fall and Mr. Matthew K Man at the Laboratory of Biomedical Imaging and Signal Processing at The University of Hong Kong for their technical assistance This work was Supported by the Hong Kong Research Grant Council (GRF HKU 7793/08M)

References

 

DC FieldValueLanguage
dc.contributor.authorChan, KCen_HK
dc.contributor.authorXing, KKen_HK
dc.contributor.authorCheung, MMen_HK
dc.contributor.authorZhou, IYen_HK
dc.contributor.authorWu, EXen_HK
dc.date.accessioned2012-08-08T08:34:03Z-
dc.date.available2012-08-08T08:34:03Z-
dc.date.issued2010en_HK
dc.identifier.citationNeuroimage, 2010, v. 49 n. 3, p. 2013-2020en_HK
dc.identifier.issn1053-8119en_HK
dc.identifier.urihttp://hdl.handle.net/10722/155548-
dc.description.abstractThe superior colliculus (SC) is a laminated subcortical structure in the mammalian midbrain, whose superficial layers receive visual information from the retina and the visual cortex. To date, its functional organization and development in the visual system remain largely unknown. This study employed blood oxygenation level-dependent (BOLD) functional MRI to evaluate the visual responses of the SC in normally developing and severe neonatal hypoxic-ischemic (HI)-injured rat brains from the time of eyelid opening to adulthood. MRI was performed to the normal animals (n = 7) at postnatal days (P) 14, 21, 28 and 60. In the HI-injured group (n = 7), the ipsilesional primary and secondary visual cortices were completely damaged after unilateral ligation of the left common carotid artery at P7 followed by hypoxia for 2 h, and MRI was performed at P60. Upon unilateral flash illumination, the normal contralateral SC underwent a systematic increase in BOLD signal amplitude with age especially after the third postnatal week. However, no significant difference in BOLD signal increase was found between P14 and P21. These findings implied the presence of neurovascular coupling at the time of eyelid opening, and the progressive development of hemodynamic regulation in the subcortical visual system. In the HI-injured group at P60, the BOLD signal increases in both SC remained at the same level as the normal group at P28 though they were significantly lower than the normal group at P60. These observations suggested the residual visual functions on both sides of the subcortical brain, despite the damages to the entire ipsilesional visual cortex. The results of this study constitute important evidence on the progressive maturation of visual functions and hemodynamic responses in the normal subcortical brain, and its functional plasticity upon neonatal HI injury. © 2009 Elsevier Inc. All rights reserved.en_HK
dc.languageengen_US
dc.publisherAcademic Press. The Journal's web site is located at http://www.elsevier.com/locate/ynimgen_HK
dc.relation.ispartofNeuroImageen_HK
dc.subjectDeveloping brainen_HK
dc.subjectDiffusion tensor imagingen_HK
dc.subjectFunctional MRIen_HK
dc.subjectNeonatal hypoxic-ischemic injuryen_HK
dc.subjectSuperior colliculusen_HK
dc.subjectVisionen_HK
dc.subject.meshAnimalsen_US
dc.subject.meshBrain Mappingen_US
dc.subject.meshHypoxia-Ischemia, Brain - Pathologyen_US
dc.subject.meshImage Processing, Computer-Assisteden_US
dc.subject.meshMagnetic Resonance Imagingen_US
dc.subject.meshRatsen_US
dc.subject.meshRats, Sprague-Dawleyen_US
dc.subject.meshSuperior Colliculi - Growth & Development - Pathologyen_US
dc.titleFunctional MRI of postnatal visual development in normal and hypoxic-ischemic-injured superior colliculien_HK
dc.typeArticleen_HK
dc.identifier.emailZhou, IY: izhou@hku.hken_HK
dc.identifier.emailWu, EX: ewu1@hkucc.hku.hken_HK
dc.identifier.authorityZhou, IY=rp01739en_HK
dc.identifier.authorityWu, EX=rp00193en_HK
dc.description.naturelink_to_subscribed_fulltexten_US
dc.identifier.doi10.1016/j.neuroimage.2009.10.069en_HK
dc.identifier.pmid19879366-
dc.identifier.scopuseid_2-s2.0-71849094738en_HK
dc.identifier.hkuros177189-
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-71849094738&selection=ref&src=s&origin=recordpageen_HK
dc.identifier.volume49en_HK
dc.identifier.issue3en_HK
dc.identifier.spage2013en_HK
dc.identifier.epage2020en_HK
dc.identifier.isiWOS:000273626400009-
dc.publisher.placeUnited Statesen_HK
dc.identifier.scopusauthoridChan, KC=34968940300en_HK
dc.identifier.scopusauthoridXing, KK=35886305100en_HK
dc.identifier.scopusauthoridCheung, MM=24333907800en_HK
dc.identifier.scopusauthoridZhou, IY=35424838500en_HK
dc.identifier.scopusauthoridWu, EX=7202128034en_HK
dc.identifier.citeulike6067626-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats