phacoemulsification in long and short eyes dr. memarzadeh md
Post on 22-Feb-2016
30 Views
Preview:
DESCRIPTION
TRANSCRIPT
IN THE NAME
MY GOD
1
Phacoemulsification in long
and short eyes
Dr. memarzadeh MD 1387/11/30
1387-11-30
Dr memarzadeh MDophthalmologist
2
3
4
Features of long axial length eyesrelating to phacoemulsifcation
1. Deep AC2. More mobility of lens3. Zonular laxity4. More liquefied vitreous5. Thin sclera6. Younger age onset cataract7. The degree of maturity of cataract on SLE examination
dose not commensurates with the visual loss
5
preoperation evaluations
1. Careful SLE and fundus examination specially for macula and peripheral retinal breaks, holes, sever atrophic changes , CNV.
2. In doubtful situations PVA testing may helps
6
Myopic retina
7
Pre op examination cont…
IOL power calculation:1. Long axial length and posterior stapyhloma
are of important sources of miss calculation.2. Both A scan and B scan should be done concurrently to obtain the axial length from exact foveal fixation point.3. The best formulas are SRK T and Holladay.
8
...Intra operative considerations Anesthesia: Topical anesthesia is performed to decrease
the risk of glob laceration but be aware that myopes are more photophobic and so less cooperative there by periocular anesthesia can be another option but be careful of globe laceration.
9
Intra operative cont…
Wound constriction: Large tunnel incision causes corneal distortion
which blurs visibility, hence shorter clear corneal incision (1.5 mm) is preferred.
Capsulorhexis: The size of rhexis should be just smaller than
optic diameter to minimize PCO but no too small to interfere the view of peripheral retina.
10
Intra operative cont…
Hydrodisection: Because many myope patients are young there
is tenacious corticocapsular adhesions therefore you may need inject multiple small volumes of BSS at various places.
11
12
Intra operative cont…
Nuclear emulsification:1. As myopes have fragile zonula, liquefied vitreous, thin sclera, instruction of probe exerts a sudden positive
pressure that pushes the iris peripherally and deepens the AC (breathing pupil phenomena) adjustment of bottle height or positive air pressure can minimize the problem.
2. Kelman bent needle is preferred because allows better approach without additional corneal distortion.
3. The maturity of cataract can be assessed deceptively soft in SLE hence increments of power is required to minimize stress on zonula and capsule.
13
14
15
پوزش عرض ضمنباالی حجم بدلیل
LECTUER ادامهپذیر امکان ها اسالید
نیاز صورت در نمیباشدواحد به لطفا ادامه بهمرکز بصری و سمعیفیض درمانی آموزشیشماره با یا و مراجعه
تلفن 03114476010
تماس 392داخلی نمائید حاصل
تشکر با
top related