関: retinal blood vessel、retinal vessel

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/04/20 14:48:18」(JST)

wiki en

Diagram showing the position of the pecten oculi within a bird eye

The pecten or pecten oculi is a comb-like structure of blood vessels belonging to the choroid in the eye of a bird. It is a non-sensory, pigmented structure that projects into the vitreous body from the point where the optic nerve enters the eyeball.^[1] The pecten is believed to both nourish the retina and control the pH of the vitreous body.^[2] High level of enzyme alkaline phosphatase activity in pecten oculi, has been linked to transport of nutrient molecules from highly vascularized pecten oculi into vitreous and then into retinal cells for nourishment.^[3] It is present in all birds and some reptiles.^[4]

In the vertebrate eye, blood vessels lie in front of the retina, partially obscuring the image. The pecten helps to solve this problem by greatly reducing the number of blood vessels in the retina and leading to the extremely sharp eyesight of birds such as hawks.^[5] The pigmentation of the pecten is believed to protect the blood vessels against damage from ultraviolet light. Stray-light absorption by melanin granules of pecten oculi is also considered to give rise to small increments in temperature of pecten and eye; this may offer increased metabolic rate to optimize eye physiology in low temperatures at high-altitude flights.^[6] The structure varies across bird species and is conical in the kiwi, vaned in the ostrich and pleated in most other birds.^[7]

References

^ Walls (1942), The Vertebrate Eye and its Adaptive Radiation, Hafner, ISBN 0-02-854430-7
^ Kiama, S G.;J. N. Maina;J. Bhattacharjee and K. D. Weyrauch (2001) Functional morphology of the pecten oculi in the nocturnal spotted eagle owl (Bubo bubo africanus), and the diurnal black kite (Milvus migrans) and domestic fowl (Gallus gallus var. domesticus): a comparative study. Journal of Zoology 254: 521-528
^ Bawa S R and YashRoy R C (1972) Effect of dark and light adaptation on the retina and pecten of chicken. Experimental Eye Research, vol. 13, pp. 92-97.https://www.researchgate.net/publication/18108932_Effect_of_dark_and_light_adaptation_on_the_retina_and_pecten_of_chicken?ev=prf_pub
^ Bonney, Rick; Rohrbaugh, Jr., Ronald (2004), Handbook of Bird Biology (Second ed.), Princeton, NJ: Princeton University Press, ISBN 0-938027-62-X
^ Claire Ainsworth, Clair; Le Page, Michael (August 11, 2007), "Evolution's greatest mistakes" (PDF), New Scientist (195.2616)
^ Bawa S R and YashRoy R C (1974) Structure and function of vulture pecten. Cells Tissues Organs Vol. 89 pp. 473-480.https://www.researchgate.net/publication/231569868_Structure_and_function_of_vulture_pecten?ev=prf_pub
^ S G Kiama, J Bhattacharjee, J N Maina, and K D Weyrauch (December 1994), "A scanning electron microscope study of the pecten oculi of the black kite (Milvus migrans): possible involvement of melanosomes in protecting the pecten against damage by ultraviolet light", Journal of Anatomy 185 (Pt 3): 637–642, PMC: 1166670, PMID 7649799

External links

Electron microscopy photos of the pecten in the black kite (Milvus migrans)

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 美容適応としてのボツリヌス毒素：特定部位治療 botulinum toxin for cosmetic indications treatment of specific sites
2. 眼瞼下垂症の概要 overview of ptosis
3. 顔面への軟部組織充填剤の注入が危険な部位 anatomic danger zones for facial injection of soft tissue fillers
4. 眼筋型重症筋無力症 ocular myasthenia gravis
5. 神経筋接合部の電気診断学的評価 electrodiagnostic evaluation of the neuromuscular junction

English Journal

Genetic algorithm based feature selection combined with dual classification for the automated detection of proliferative diabetic retinopathy.

Welikala RA1, Fraz MM2, Dehmeshki J3, Hoppe A4, Tah V5, Mann S6, Williamson TH7, Barman SA8.
Computerized medical imaging and graphics : the official journal of the Computerized Medical Imaging Society.Comput Med Imaging Graph.2015 Jul;43:64-77. doi: 10.1016/j.compmedimag.2015.03.003. Epub 2015 Mar 20.
Proliferative diabetic retinopathy (PDR) is a condition that carries a high risk of severe visual impairment. The hallmark of PDR is the growth of abnormal new vessels. In this paper, an automated method for the detection of new vessels from retinal images is presented. This method is based on a dua
PMID 25841182

Indocyanine green angiographic evidence of choroiditis in scleroderma.

Abdellatief A1, Balasubramaniam SC, Grube TJ, Gonzalez Santiago TM, Osborn TG, Pulido JS.
Retinal cases & brief reports.Retin Cases Brief Rep.2015 Summer;9(3):231-4. doi: 10.1097/ICB.0000000000000146.
PURPOSE: The purpose of this case report was to demonstrate evidence of indocyanine green angiography leakage consistent with choroiditis in a patient with scleroderma.METHODS: In this case report, the patient underwent a variety of tests and examinations, including systemic evaluation, full ocular
PMID 25769052

Severity of retinopathy parallels the degree of parasite sequestration in the eyes and brains of malawian children with fatal cerebral malaria.

Barrera V1, Hiscott PS1, Craig AG2, White VA3, Milner DA4, Beare NA5, MacCormick IJ6, Kamiza S7, Taylor TE8, Molyneux ME9, Harding SP1.
The Journal of infectious diseases.J Infect Dis.2015 Jun 15;211(12):1977-86. doi: 10.1093/infdis/jiu592. Epub 2014 Oct 28.
BACKGROUND: Malarial retinopathy (MR) has diagnostic and prognostic value in children with Plasmodium falciparum cerebral malaria (CM). A clinicopathological correlation between observed retinal changes during life and the degree of sequestration of parasitized red blood cells was investigated in oc
PMID 25351204