Early results of circularity and centration of capsulotomy prepared by three different methods

AIM:To compare the difference of capsulotomy produced by precision pulse capsulotomy(PPC),manual(M-CCC),and femtosecond laser assisted capsulotomy(FLAC)in relation to intraocular lens(IOL)centration,circularity and its effect on visual outcomes.METHODS:Prospective,non-randomized comparative study conducted at LV Prasad Eye Institute,Hyderabad,India.Sixty eyes of 52 patients were grouped into 3(FLAC,PPC and M-CCC)based on capsulotomy techniques used.Twenty consecutive eyes with uneventful phacoemulsification and with no comorbidities affecting the capsulotomy or visual outcome were included in each group.The main outcome measure was IOL centration in relation to capsulotomy and pupil.Secondary outcome measures were post-operative visual acuity,manifest refraction and aberration profile between groups.RESULTS:At 5 wk the visual,refractive outcomes and endothelial cell density were comparable between the 3 groups.The median circularity index of FLAC was statistically significantly different to M-CCC or PPC(1-10)groups(P<0.01)but PPC(11-20)was comparable to FLAC.Decentration of IOL center in relation to capsulotomy was seen only between the PPC(1-10)group and FLAC group(P=0.02).The IOL was well centered in relation to the pupil in all the groups(P=0.46).The quality of vision parameters like the higher order aberrations,spherical aberration,coma,trefoil,modular transfer function,and Strehl ratio were comparable between the groups.CONCLUSION:Our study shows that despite differences in the morphology of capsulotomy produced by PPC,M-CCC,FLAC a well-centered IOL can be achieved.The measured capsular morphology parameters do not affect visual outcomes.

Changes in post-keratoplasty astigmatism after suture removal:refraction vs tomography vs aberrometry

AIM:To analyse the changes in magnitude and orientation of astigmatism after suture removal(SR)in keratoplasty eyes as measured by refraction,tomography,and aberrometry.METHODS:Twenty-six eyes of 25 patients after optical keratoplasty requiring SR to reduce the astigmatism during the follow-up period were prospectively included.Eyes with poor quality topography scans or if there were no sutures in the steepest semi meridian were excluded.Corrected distance visual acuity(CDVA),manifest refraction,corneal tomography and aberrometr y were per formed on all patients before and after SR.RESULTS:The mean age of the patients was 40.8±14.4 y.Penetrating keratoplasty was performed in 23 eyes(89%)and deep anterior lamellar keratoplasty was done in 3 eyes(11%).There was a statistically significant reduction in the magnitude of refractive,tomographic and aberrometry astigmatism after SR(P<0.001)at 2 h after suture removal.The mean net reduction of the astigmatism was greater as measured by corneal tomography compared to refractive astigmatism(P<0.05).There was no statistically significant change in refractive astigmatism between 2 h and 2 mo after SR(P=0.55).Vector calculations demonstrated a greater amount of undercorrection in the tomography group and the rotational error was more towards counterclockwise direction.Mean monocular log MAR CDVA improved from 0.57 D to 0.49 D after SR(P=0.002).CONCLUSION:The net reduction in the magnitude of astigmatism after SR is greater in the tomography and aberrometry groups.With one episode of SR,there is no difference in the aberration profile.