Variation in the Anatomy of the Normal Human Optic Chiasm: An MRI Study.

Journal of Neuro-ophthalmology : the Official Journal of the North American Neuro-Ophthalmology Society
Nicholas S I BoslerChristian J Lueck

Abstract

Compression of the optic chiasm typically leads to bitemporal hemianopia. This implies that decussating nasal fibers are selectively affected, but the precise mechanism is unclear. Stress on nasal fibers has been investigated using finite element modeling but requires accurate anatomical data to generate a meaningful output. The precise shape of the chiasm is unclear: A recent photomicrographic study suggested that nasal fibers decussate paracentrally and run parallel to each other in the central arm of an "H." This study aimed to determine the population variation in chiasmal shape to inform future models. Sequential MRI scans of 68 healthy individuals were selected. 2D images of each chiasm were created and analyzed to determine the angle of elevation of the chiasm, the width of the chiasm, and the offset between the points of intersection of lines drawn down the centers of the optic nerves and contralateral optic tracts. The mean width of the chiasm was 12.0 ± 1.5 mm (SD), and the mean offset was 4.7 ± 1.4 mm generating a mean offset:width ratio of 0.38 ± 0.09. No chiasm had an offset of zero. The mean incident angle of optic nerves was 56 ± 7°, and for optic tracts, it was 51 ± 7°. The human optic chiasm is "H" shaped, not ...Continue Reading

References

Dec 1, 1992·Visual Neuroscience·B E Reese, G E Baker
Sep 1, 1969·Journal of Neurosurgery·R Bergland
Dec 31, 2002·Investigative Ophthalmology & Visual Science·Bernd SchmitzBarbara Käsmann-Kellner
Nov 24, 2004·Investigative Ophthalmology & Visual Science·Ian A SigalC Ross Ethier
Mar 10, 2005·Journal of Neuro-ophthalmology : the Official Journal of the North American Neuro-Ophthalmology Society·Gawn G McIlwaineT Malcolm Chrisp
Dec 18, 2007·Ophthalmology·Gregory S KosmorskyRichard L Drake
Jun 20, 2008·Journal of Neuro-ophthalmology : the Official Journal of the North American Neuro-Ophthalmology Society·Joel S Glaser
Apr 9, 2010·Surgical and Radiologic Anatomy : SRA·Hyung-Sun WonSun Ho Kim
May 21, 2014·Journal of Biomechanics·Xiaofei WangChristian J Lueck
Jul 1, 2014·Journal of Neuro-ophthalmology : the Official Journal of the North American Neuro-Ophthalmology Society·Xiaofei WangChristian J Lueck
Oct 27, 2015·AJR. American Journal of Roentgenology·In Ho LeeMichael V Boland
Nov 17, 2015·Investigative Ophthalmology & Visual Science·Neeranjali S JainChristian J Lueck
May 6, 2016·Frontiers in Neuroanatomy·Markus AxerKatrin Amunts
Apr 20, 2018·The Neuroradiology Journal·Shoichiro OtakeWilliam Tc Yuh

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.

Related Papers

Canadian Medical Association Journal
D PARKINSON
Archives D'ophtalmologie Et Revue Générale D'ophtalmologie
P Vérin
Revue d'oto-neuro-ophtalmologie
P CerneaI Cornea
Archives D'ophtalmologie Et Revue Générale D'ophtalmologie
H Hamard, J L Couderc
Archives D'ophtalmologie Et Revue Générale D'ophtalmologie
H Hamard
© 2021 Meta ULC. All rights reserved