Refractive impact of the yag laser after cataract surgery
Dr. Daniele ARON-ROSA
Paris - France

Most of the coomplications of Yag laser capsulotomy can be avoided

1) By pre and post treating the patient
•	Indometacine 0.1 from 1 day pre yag to 1 week postop
•	Apropriate YAG : tem00 short nanosec pulses or better pico or femtosec pulses

•	   

second pulses

The shorter the pulses the less side effects
•	limited : thermal effects
•	resulting less mouvement of the implant 
•	less seondary en largement of the PC

The YAG capsulotomy causes back ward displacement of the IOL, wisch is significantly higher
 with plate IOL & large capsulotomies

Backward mouvements were studied by
•	Aron Rosa 1979 : J. AppPhys 1979
•	                            : J. catarct& refract Surg 1995
•	Final O : J catarct refract surg 1999
PC AND IOL BACWARD MVTS
•	IF the size  of capsulotomy 3.44 +- 026mm
•	mean increase of the AC = 25 micron ( 9 to 55)
•	the larger the more backward displacement
•	 

VARIATION OF BACKWARD MVTS/
At day 1: 9 to 28 mic for the 3 pieces foldable IOL
15 to 55 mic for the plate IOL
 
AT 5 WEEKS  POST YAG

\	NO significant changes for the 3 pieces IOL
\	Tendency to move back 16 to 65 microns for the plate IOL

HYPEROPIC SHIFT

\	Irrelevant for the 3 piecesIOL
\	More for the plate IOL : 0.08 to 0.5 SE
\	:
\	 

\	 

CONCLUSION:

\	NDYAG capsulotomy, causes a backward movement of the iol 

\	precisely measured with he dual beam partial coherent interferometer

=

Plate haptics tend to be compressed in the shrinking of the capsule and vault bacward ,increasing the capsular tension .After the capsule is realease, e lens vaults bacward even more , and may dislocate into the vitreous if PC is large enough. 

The nature of the YAG LASER 
influences the evolution of the PC SIZE:
\	Nano or picosec monomode( tem 00)do not generate PC enlargement of PC.
\	NANO multimode necessitating more energy to reach OBD, is more deflagrating and causes more enlargement of PC , has more side effects and causes more complications 
\	 idiopathiques
\	bilatérales: 60 % idiopathiques
CONCLUSIONS 

\	 WITH a good YAG and a reasonabely sized PC AND A 3 PIECES FOLDABLE IOL  
\	PC will generate minimal refractive changes
\	 infectieux
\	 héréditaire
–	oculaire
–	associé à des maladies générales