Korean J Ophthalmol.  2014 Apr;28(2):150-154. 10.3341/kjo.2014.28.2.150.

Changes in the Accommodation-convergence Relationship after the Artisan Phakic Intraocular Lens Implantation for Myopic Patients

• Ryu IH
• Han J
• Lee HK
• Kim JK
• Han SH

• KMID: 1792108
• DOI: http://doi.org/10.3341/kjo.2014.28.2.150

Abstract

PURPOSE
To evaluate the change of accommodation-convergence parameters after implantation of Artisan phakic intraocular lens (PIOL).
METHODS
Prospective study for the patients with the Artisan PIOL implantation was performed. A total of 37 patients (3 males and 34 females) enrolled the study. Preoperatively, convergence amplitude, the stimulus accommodative convergence per unit of accommodation (AC/A) ratio and the near point of convergence (NPC) were evaluated. After the Artisan PIOL implantation, the identical evaluations were repeated at 1 week, 1, 3, and 6 months after the surgery.
RESULTS
Mean age was 24.3 +/- 4.8 years old, and preoperative refractive error was -8.92 +/- 4.13 diopters (D). After the implantation, mean refractive errors significantly decreased to within +/-1.00 D, and noticeable complications were not found. The convergence amplitude and the stimulus AC/A ratio increased 1 month after the surgery, but progressively stabilized afterward to near preoperative values. NPC didn't show any significant change over follow-up period up to 6 months.
CONCLUSIONS
These results regarding implantation of the Artisan PIOL revealed the increase of accommodation-convergence relationship within first 1 month after the surgery, but progressive stabilization was noted during follow-up periods.

Keyword

Convergence; Ocular accommodation; Phakic intraocular lenses

MeSH Terms

*Accommodation, Ocular
Adult
*Convergence, Ocular
Female
Follow-Up Studies
Humans
Lens Implantation, Intraocular/*methods
Male
Myopia/*diagnosis/*surgery
*Phakic Intraocular Lenses
Postoperative Period
Prospective Studies
Refractive Surgical Procedures/methods
Treatment Outcome
Visual Acuity
Young Adult

Figure

• 

  Fig. 1 The stimulus accommodative convergence per unit of accommodation (AC/A) ratio before and after the implantation of Artisan phakic intraocular lens. Preop = preoperative; Postop = postoperative. *Statistically significant compared to preoperative value by Wilcoxon signed-rank test.

• 

  Fig. 2 The near point of convergence before and after the implantation of Artisan phakic intraocular lens.

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