Microsoft PowerPoint - optic-102Aug [相容模式]

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鲤岭喻
7 years ago
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1 101optics Optics & Refraction 史敏秀醫師

2 Emmetropia ( 正視眼 ) 可看清 ( 遠點 ) 無限遠 (6m) no refractive error, far point is infinity (6m) Cornea: 43 D Lens: D Axial length: 23.5 mm 看遠清楚看近 ( 未調節 ) 模糊看近 ( 調節 ) 清楚看近 ( 未調節, 加老花眼鏡 ) 清楚

3 Ametropia: refractive errors Myopia ( 近視 ) I Hyperopia ( 遠視 )II Astigmatism ( 散光, 亂視 )

4 Refractive State of Eyes 可看清楚的最遠距離 D (diopter, 屈光度 ) =1/ focal length of a lens (m) =1/ 遠點 ( 公尺 ) 正視 : 無限遠近視 : 眼 ( 網膜 ) 前 (-4.0 D myopia---> 25 cm) 遠視 : 眼 ( 網膜 ) 後 (+4.0D hyperopia---> 25 cm behind the retina)

5 Myopia Inheritance (nature) v.s. environment (nurture) congenital myopia pseudomyopia pathological (high) myopia Correction with minus (concave) spherical lenses 看遠模糊看近 ( 遠點 ) 清楚軸性 ( 過長 ) 屈光性 ( 過強 ) 白內障 ( 回春 )

6 Myopia in Taiwan Preschool or school onset early onset, fast progression axial elongation (1 mm ~ 2.5 diopter) Complication of high myopia (>6~8 D) Presenile cataract( 早發性白內障 ) Glaucoma( 青光眼 ) Retinal detachment( 視網膜剝離 ) Maculopathy( 黃斑部病變 )

5 diopter) Complication of high myopia (>6~8 D) Presenile

7 近視率 (%) 小學一年級小學六年級國中三年級高中三年級 1986 年 1990 年 1995 年 2000 年 2006 年平均度數 (*100) 1983 年 1995 年 2000 年小學六年級國中三年級高中三年級

6 74 76.4 80.7 77.1 76.3 75.2 84.1 84.2 85.

8 Prevention and treatment of myopia Cycloplegia ( 散瞳劑 ) (atropine) Multifocal glasses Rigid gas permeable contact lenses Orthokeratology ( 角膜塑型 ) Spectacle lenses Contact lenses Intraocular lenses Refractive surgery (LASIK, PRK )

$Contact lenses Intraocular lenses Refractive surgery$

9 Cycloplegia ( 睫狀肌麻痺劑 ) 種類 : tropicamide 0.4~1% ( 短效 ), atropine 0.1~1% ( 長效 ) 目的 : 正確驗光, 抑止度數增加副作用 : 刺痛散瞳調視困難眼壓升高全身性

10 Hyperopia Low grade (< 2D) hyperopia is usual before 7 y/o Latent (can compensate with accommodation) v.s. manifest hyperopia Correction with plus (convex) spherical lenses 看遠模糊遠點眼後看遠 ( 調節 ) 清楚軸性 ( 太短 ) 屈光性 ( 太弱平 ) 無水晶體

11 Spherical Lenses Convex (plus) Concave (minus) Sph +3.0D Sph 3.0D

12 Astigmatism Disparity of curvature of the cornea or lens in different meridian 散光 ( 亂視 ): 如果角膜水平與垂直的弧度不同, 影像經由不同的弧度聚焦後形成幾個不同的焦點造成散光規則性散光的角膜多為橢圓形而非正常球型 Regular astigmatism Irregular astigmatism: keratoconus, corneal scar, cataract

13 Vision from astigmatic eye

14 Regular Astigmatism 強弱軸交角成 90 度, 且在瞳孔中央 With the rule v.s. against the rule 順向性 (cyl(-) 180, 橫置橄欖球, 小孩 ), 逆向性 ( 老人 ) Compound v.s. mixed v.s. simple

15 Astigmatic Lenses Cylindric lenses cyl. 3.0 x 90 cyl x 90

16 Regular Astigmatism with the rule ( 順向 ) v.s. against the rule ( 逆向 ) cyl 1.5 X 0 cyl 1.5 X 90 compound v.s. mixed, v.s. simple

17 Toric Transposition Spherocylindrical Combination +4.0 cyl 1.0 X cyl +1.0 X Crossed cylinder

18 單純散光合併散光近視 + 散光 -2.0/-1.0*180 等於 -3.0/+1.0* 遠視 + 散光 +2.0/-1.0*180 等於 +1.0/+1.0*

19 矯正視力時, 若需戴用如下眼鏡 : 球面透鏡 +3D, 圓柱透鏡 -3D 角度軸九十度, 以看清楚遠方視標時, 其屈光診斷為 A) with-the-rule simple hyperopic astigmatism B) against-the-rule simple hyperopic astigmatism C) with-the-rule compound myopic astigmatism D) against-the-rule compound myopic astigmatism 散光鏡片度數的記載 +2.0D sph with cyl -3.0D ax 90 與下列何者是相當的? A) -2.0D sph with cyl +3.0D ax 180 B) -2.0D sph with cyl -3.0D ax 90 C) -1.0D sph with cyl +3.0D ax 180 D) -1.0D sph with cyl -3.0D ax 90 張小姐 26 歲, 原本就有近視散光, 原來的眼鏡已經戴了 4 年, 最近覺得看東西模糊, 所以到眼鏡行想重配眼鏡老闆告知眼睛有問題, 所以至眼科檢查, 發現張小姐的度數和原來的眼鏡比較, 右眼近視增加 -2.0D, 散光增加 5.0D, 矯正視力為 6/20, 左眼散光增加 2.0D, 矯正視力為 6/6.7, 裂隙燈及視網膜檢查皆正常張小姐工作為室內設計, 下列何項治療為優先選擇? A) 戴針孔眼鏡 B) 戴軟式日拋隱形眼鏡 C) 戴硬式透氧隱形眼鏡 D) 近視及散光雷射手術

20 Spherical equivalent ( 球面當量 ) to refer to an eye's effective focusing power if only spherical aberration were present. SER can be defined as: sphere + cylinder/2 w A spherical power whose focal point coincides with the circle of least confusion of a spherocylindrical lens. The spherical equivalent of the prescription 3 D sphere 2 D cylinder axis 180º is equal to 4 D. Exp. 4.0 cyl 3.0 X cyl 1.0 X 0

SER can be defined as: sphere + cylinder/2 w A spherical power whose focal point coincides with the

21 Refractive errors Anisometropia( 不等視 ): difference in RE between two eyes (> 2D) Aniseikonia( 不等像 ): difference in image size between two eyes Retinal image size ( 視網膜 ) Spectacle ( 眼鏡 ) Intraocular correction lenses( 人工水晶體 ) Axial myopia = E (emmetropia) >> E > E Axial hyperopia = E << E < E Refractive myopia << E = E < E Refractive hyperopia >> E = E > E Contact lens correction 臨床上, 使用下列何種儀器檢查患者, 較無法得知受檢者的眼球屈光狀態? A) 自動屈折計 (automated refractometer) B) 網膜檢影鏡 (retinoscope or skiascope) C) 直接眼底鏡 (direct ophthalmoscope) D) 眼球突出計 (exophthalmometer)

23 ( )sph (+)sph ( )cyl (+)cyl

24 Types of Optical Correction Spectacle Lenses front surface: plus power back surface: minus power astigmatism: minus cylinder Contact Lenses More effective than spectacle for myopia 近視更有效, 遠視反之 (>4D) Less effective for hyperopia Intraocular Lenses IOL power = A 2.5L 0.9K 普通眼鏡 ( 頂間距離 12 毫米 ) 戴 -6.5 屈光度鏡片矯正的近視眼, 若換戴隱形眼鏡時, 則 A) 所需鏡片度數增加 ( 如 :-8.00) B) 所需鏡片度數減少 ( 如 :-6.00) C) 所需鏡片度數不變 D) 影像變小

25 Automated Refractometer VD: vertex distance ( 頂間距離 ) 0,12,15 mm Cyl( )or (+): cylinder S: sphere C: cylinder A: axis of cylinder S. E.: spherical equivalence ( 球面當量 )(S+C/2) PD: pupillary distance ( 瞳孔距離 )

26 Visual Acuity distance at which the letter is read distance at which it should normally be read Snellen E chart (20 ft): 20/16, 20/20, 20/25, 20/40.. Landolt C chart (5 m): 1.2, 1.0, 0.9, 0.8, 0.7 size of E or C letter

27 20/20 的視標 E 在距離 20 feet 處佔視角 5 分角 (5min), 大小約為 8.7 mm (When is small, tan.) 每一分角約為 2 r/360 *60 = 2 * 3.14 * 6 * 1000/360 * 60 = mm 20/40 的視標 E, 佔視角 10 分角 (10 min) E E E ft

28 Distance Visual Acuity Right eye (Vod) left eye (Vos) Bare eye or PG best corrected VA At least >3 correct in one line 0.1 better or <0.1/5m 0.1/?m CF or ND(counting finger or digit number)/?cm HM(hand motion)/?cm SL(+)or LP(+) (sight of light only) SL( ) or NLP (no light perception)

29 VA / in 5 m 1.0/2.5m 0.02 ND/1m Record: Bare-eye VA or VA with PG (present glasses) or VA with best correction exp: Vod: 0.2(1.0x-1.5/-1.0x180 0) Vos: 0.3(NC)(0.4xPH)

30 Red-green (duochrome) test 紅綠雙色試驗可見光色散差 : 綠黃紅 A A 近視 : 紅底視標較清楚黃在網膜前 ( 仍近視 ) 再加近視度數綠底視標較清楚黃在網膜後 ( 變遠視 ) 須減少近視度數限制 : 視力至少 0.6 以上, 過度調節, 色盲? 在驗光時以紅色視標及綠色視標分別檢查視力, 患者若表示綠色視標較清晰, 則應如何修正矯正鏡片度數 A) 增加凹透鏡或減少凸透鏡度數 B) 增加凸透鏡或減少凹透鏡度數 C) 增加負圓柱鏡或減少正圓柱鏡度數 D) 增加正圓柱鏡或減少負圓柱鏡度數

31 Subjective Refraction( 主動驗光 ) 1. 霧視 : 焦線在網膜前 2. 粗調遠近度數 : 少配, 至少散光圖 30 準則 : 散光全矯正 (<2D) 4. 微調遠近度數 : 至紅綠試驗 : 透鏡全矯正 6. 雙眼平衡 : 優勢眼

33 Pinhole ( 針孔 ) 原理 : 增加景深 (infinity) 降低網膜模糊度 The most useful diameter: 1.2 mm for 5 D to + 5D Pinhole visual acuity: improved for optical irregularity, decrease for central visual disorder (macula)

34 Accommodation ( 調視 ) Resulting from increasing the tonus of ciliary muscle and relaxation of zonule more biconvex lens ( 水晶體 ) with greater refractive power 老花眼 : ( 矯正有無 ) 看遠清楚, 看近不清楚老花度數 (add): 看清遠和近的度數差

35 Accommodation Near point( 近點 ): the point at which the eye is focused when accommodation is fully active Amplitude of accommodation (diopter): total number of diopters an eye can accommodation Range of accommodation (meter): far to near point, the extent of clear vision of an eye (exp. From 2 m to 50 cm)

36 Presbyopia ( 老花眼 ) gradual loss of accommodation resulting from loss of elasticity of lens capsule and lens substance Begin after age 40 Depend on refractive error, pupil size (depth of focus), nature of task. Correction with convex lens

37 年齡度數和老花正視眼近點 :40 歲 (25 cm),50 歲 (40 cm),60 歲 (1 m) 老花度數 :40 歲 (1 D),50 歲 (2 D),60 歲 (3 D) 遠視 1D 近點 : 40 歲 (50 cm),50 歲 (67 cm),60 歲 ( ) 近視 1D, 調視距離 :40 歲 (1 m~20 cm),50 歲 (1 m~30 cm),60 歲 (1 m~50 cm)

38 Bifocals ( 雙光眼鏡 )

39 Progressive addition lenses ( 漸進多焦點寬頻兒控 ) 優點 : 美觀多種明視距離無環狀盲點, 無影像跳躍缺點 : 周邊模糊近用區小改變使用習慣昂貴散光干擾區遠用.. 近用漸近變焦散光干擾區限制 : 早期老花 (50 歲前 )

40 Multifocal intraocular lens Multifocal contact lens

第一章緒論

第一章緒論第五章實證結果第一節敘述統計表 11 表 12 分別為男女癌症, 實驗組與控制組樣本之基本特性此為罹癌前一年度樣本特性由於我們以罹癌前一年有在就業, 即投保類別符合全民健康保險法中所規定之第一類被保險人, 且年齡介於 35 至