The Apparent Accommodation after Implantation of Posterior Chamber Intraocular Lenses: Acrylic and Silicone

PURPOSE: We compared the apparent accommodative power of acrylic intraocular lens(IOL) with silicone IOL after implantation of IOL into the bag. METHODS: In 36 senile catatact patients(40 eyes)visited St. Mary's hospital from July 1999 to June 2000, the IOL was inserted into the capsular bag after continuous curvilinear capsulorhexis. All of them were over 60 years old. We checked corrected visual acuity, pupil diameter and apparent accommodative power by accommodometer(AA2000, Nidek, Japan) preoperatively and 1 day, 1 month, 2 months after surgery. The used IOLs were two groups, ones are Acrysof (Alcon, U.S.A.) in 20 eyes and the others are Soflex (Chiron vision, U.S.A.) in 20 eyes. RESULTS: The investgation revealed that the apparent accommodative power reached its peak at 1 month after surgery. There was no stastically significant difference(p>0.05) between acrylic IOL and silicone IOL in apparent accommodative power at 2 months after surgery. CONCLUSIONS: The analysis revealed that the pupil size had significant negative correlations with apparent accommodative power at each other group, whereas corrected visual acuity and refraction error showed no relationship with apparent accommodative power.

The Measurement of the Apparent Accommodation with AA-2000 Accommodometer

We compared the apparent accommodative power of 35 pseudophakic patients(43eyes) receiving posterior chamber lens in the bag with 34 normal persons(34eyes) by using AA-2000 accommodometer and evaluated the correlation between apparent accommodation and various factors like age, corrected visual acuity, refractive error, pupillary diameter, anterior chamber depth, or change of the anterior chamber depth in pseudophakic eyes. The mean apparent accommodative power was 1.41 +/- 0.62 diopter(D) in pseudophakic eyes and 1.58 +/- 1.71 D in phakic eyes and there was no stastistically significant difference between two groups. However, in cases younger than 55 years old, the apparent accommodative power was 1.34 +/- 0.48 D in 17 pseudophakic eyes and 2.51 +/- 2.31 D in 14 phakic eyes and there was statistically significant(p<0.05). Among the various factors, pupillary diameter appeared to be correlative to the apparent accommodative power in pseudophakic eyes. The smaller pupillary diameter, the greater accommodative power. Otherwise, another factors were not correlative to the apparent accommodative power.

Apparent Accommodation in Posterior Chamber IOL Implanted Eyes

In order to evaluate the cause of apparent accommodation in pseudophakia, we performed ECCE and implanted biconvex, monofocal I0L in the bag in 24 patients(32 eyes) and followed up for more than 2 months. We measured apparent accommodation, corneal astigmatism and near visual acuity. And we also measured apparent accommodation and the changes of anterior chamber depth according to the movement of I0L and apparent accommodation according to the changes of pupil diameter in normal state before drug instillation and after instillation of either 10% phenylephrine or 2% pilocarpine. The results were as follows: 1. The mean apparent accommodation was 1.36 +/- 0.52 diopters. 2. There was negative correlation between corneal astigmatism and apparent accommodation and between cornel astigmatism and near visual acuity. 3. There was negative correlation between anterior chamber depth and apparent accommodation measured in normal state before drug instillation. And also there was negative correlation between the changes of anterior chamber depth and the changes of apparent accommodation measured after instillation of either 10% phenylephrine or 2% pilocarpine. 4. There was positive correlation between reciprocal changes of pupil diameter and apparent accommodation. So we conclude that the apparent accommodation is seemed! to be a resultant changes according to the changes of the pupil diameter.

Apparent Accommodation in Posterior Chamber IOL Implanted Eyes

In order to evaluate the cause of apparent accommodation in pseudophakia, we performed ECCE and implanted biconvex, monofocal I0L in the bag in 24 patients(32 eyes) and followed up for more than 2 months. We measured apparent accommodation, corneal astigmatism and near visual acuity. And we also measured apparent accommodation and the changes of anterior chamber depth according to the movement of I0L and apparent accommodation according to the changes of pupil diameter in normal state before drug instillation and after instillation of either 10% phenylephrine or 2% pilocarpine. The results were as follows: 1. The mean apparent accommodation was 1.36 +/- 0.52 diopters. 2. There was negative correlation between corneal astigmatism and apparent accommodation and between cornel astigmatism and near visual acuity. 3. There was negative correlation between anterior chamber depth and apparent accommodation measured in normal state before drug instillation. And also there was negative correlation between the changes of anterior chamber depth and the changes of apparent accommodation measured after instillation of either 10% phenylephrine or 2% pilocarpine. 4. There was positive correlation between reciprocal changes of pupil diameter and apparent accommodation. So we conclude that the apparent accommodation is seemed! to be a resultant changes according to the changes of the pupil diameter.

Apparent accommodation in monocular pseudophakic eyes and contact lens wearing monocular aphakic eyes

To investigate the presence of apparent accommodation in monocular pseudopakic eyes and contact lens wearing monocular aphakic eyes, we measured it in 54 monocular pseudophakic eyes (54 patients) and 40 contact lens wearing monocular aphakic eyes (40 patients). The mean apparent accommodation was 1.68+/-1.25 diopters in monocular pseudophakic eyes and 1.74+/-0.73 diopters in contact lens wearing monocular aphakic eyes, and there was no statistically significant difference between them. Apparent accommodation was not related either to type of intraocular lenses or pupil size in pseudophakic eyes and not related to target size in aphakic eyes, but it was influenced by pupil size in aphakic eyes. In the group of patients aged between 45 and 55, accommodation in phakic eyes was significantly greater than apparent accommodation in contralateral contact lens wearing monocular aphakic eyes.