Purpose: The aim of the study was to assess and compare the degree of
capsulorhexis phymosis following uncomplicated phacoemulsification cat
aract surgery in polymethylmethacrylate (PMMA) and silicone lens impla
nts. Method: Sixty-four patients were evaluated 1 day, 6 weeks and 6 m
onths following phacoemulsification cataract extraction, The anterior
capsular diameters were measured with the illuminated beam of the slit
lamp at 45 degrees and 135 degrees and the surface area of the openin
g; calculated. We have measured and compared the change in the capsulo
rhexis size for both lens types and assessed its statistical significa
nce with a paired Student's t-test. Results: A statistically significa
nt contraction of the capsulorhexis was noted in all patients within t
he first 6 weeks (p<0.001), Capsular contraction continued between 6 w
eeks and 6 months post-operatively but to a lesser extent (p<0.05). Th
e difference in the degree of phymosis between the first period (1 day
to 6 weeks) and the second (6 weeks to 6 months) was statistically hi
ghly significant for all patients (p<0.001). The capsular areas for th
e silicone lens implants were significantly smaller than for the PMMA
implants at 6 weeks and 6 months. None of our patients had a clinicall
y significant capsular contracture requiring Nd:YAG laser capsulotomy.
Conclusion: Anterior capsular contraction is commonly observed follow
ing capsulorhexis in phacoemulsification surgery. This study demonstra
tes that the maximum rate of contraction occurs in the first 6 weeks f
ollowing surgery and is more pronounced with silicone lens implants.