Ultrasonic pachymeter: a little different role.

BACKGROUND

Ultrasonic pachymeter, though primarily used in refractive surgery and in glaucoma evaluation, can evaluate and compare the change in corneal thickness following extracapsular cataract extraction (ECCE), small incision cataract surgery (SICS) and phacoemulsification.

METHOD

Six hundred patients were included in study. Patients were divided into three groups. Group 1 (200 eyes), group 2 (200 eyes) and group 3 (200 eyes) underwent ECCE, SICS, and phacoemulsification, respectively. Corneal thickness was evaluated pre-operatively and postoperatively on day 1, day 2, day 7, day 15, and day 30 by ultrasonic pachymetry.

RESULTS

Mean pre-operative corneal thickness in central, superior, inferior, nasal, and temporal quadrants is 525.35 ± 32.34 μm, 592.23 ± 35.39 μm, 595.66 ± 31.68 μm, 589.29 ± 38.07 μm, and 581.19 ± 42.31 μm, respectively. Postoperatively, a highly significant (P<0.01) increase in central corneal thickness was observed up to day 15 in ECCE, day 7 in SICS whereas it was up to day 2 in phacoemulsification. In superior quadrant, it is up to day 15 in ECCE and SICS whereas it is up to day 7 in phacoemulsification. In inferior quadrant, it was up to day 2 in all three techniques. In temporal quadrant, it is up to day 7 in ECCE and up to day 2 in SICS and phacoemulsification. In nasal quadrant, a highly significant (P<0.01) increase in corneal thickness was observed up to day 7 in ECCE and SICS whereas it was up to day 2 in phacoemulsification.

CONCLUSION

Normal central corneal thickness is 525.35 ± 32.44 μm. At midperiphery, inferior cornea has maximum corneal thickness followed by superior, temporal, and nasal cornea. Postoperatively, pre-operative value of corneal thickness and visual rehabilitation is achieved earliest in phacoemulsifiaction followed by SICS and ECCE.