正常眼壓型青光眼之角膜厚度與眼球壓力分析

Corneal Thickness and Pressure Distribution Analysis of the Eyes of Normal-Tension Glaucoma

戴吉謙(Ji-Chien Dai)

指導教授 ： 李宗翰

共同指導教授 ： 黃曼菁(Man-Ching Huang)

淡江大學/工學院/機械與機電工程學系碩士班/碩士(2011年)

https://doi.org/10.6846/TKU.2011.00957

摘要

正常眼壓型青光眼為青光眼病症的主要類型之一，多數的青光眼類型皆可以量測眼壓是否過高而察覺異狀，但正常眼壓型青光眼早期多無明顯症狀，且患者眼壓量測值皆位於正常範圍內，相較於一般青光眼病患較不易直接從眼壓上判斷病症。
青光眼是由於眼壓上升超出視神經所能負荷的範圍，使得視神經受損的一種視神經疾病，當眼壓高於視神經所能承受之限度時，便會使得視神經受損產生視野缺損，最後導致失明。目前量測的眼球內部壓力和真實眼壓仍存有誤差，中央角膜厚度即為主要的誤差因素，角膜較厚的患者眼壓容易被高估，反之低估了角膜較薄患者的眼壓，降低了青光眼判定的準確性。
本研究即為運用數值模擬分析的方式，對於正常眼壓型青光眼與角膜厚度的關係進行探討，並模擬患者眼球結構的壓力分佈及眼睛內部房水流動之情形，藉以了解角膜厚度對眼壓量測所造成的影響。

關鍵字

正常眼壓型青光眼 ； 角膜 ； 眼壓 ； 房水

並列摘要

Normal-tension Glaucoma is one of the main types of glaucoma. Most types of glaucoma can be judged by their higher intraocular pressure. But, normal-tension glaucoma (NTG) shows no obvious symptoms, and the intraocular pressure is normal in its early stage. It is hard to tell if one having NTG by simply checking intraocular pressure value.
Glaucoma is a disease of optic nerve caused by increased intraocular pressure. An elevated intraocular pressure may irreversibly damage optic nerve which resulting in a progressive, permanent loss of vision when the pressure exceeds the load of optic nerve. In NTG, the measured value of internal pressure is not the real internal pressure. The major factor to cause this discrepancy is the thickness of central corneal. The thicker is the cornea, the overestimated is the intraocular pressure. The accuracy of the glaucoma diagnosis is then mis-conducted.
This study used numerical simulation to exam the relationship of normal-tension glaucoma and corneal thickness. The pressure distribution and the flow of aqueous humor in ocular structure are found and shown to know more of the impact of the corneal thickness and the value of intraocular pressure measured.

並列關鍵字

Normal-tension glaucoma ； cornea ； intraocular pressure ； aqueous humor

參考文獻

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