J Korean Ophthalmol Soc.  2015 May;56(5):702-708. 10.3341/jkos.2015.56.5.702.

Internal Lens Signal Measured by Dual Scheimpflug Anterior Segment Analyzer

• Ro JW
• Yi KY
• Kim HK
• Hyon JY
• Wee WR
• Shin YJ

• KMID: 2121167
• DOI: http://doi.org/10.3341/jkos.2015.56.5.702

Abstract

PURPOSE
To investigate the clinical significance of the internal lens signal measured using dual Scheimpflug anterior segment analyzer (Galilei(TM), Ziemer, Switzerland) in patients receiving cataract surgery.
METHODS
The present study included 151 eyes of 148 patients who received surgery for senile cataracts from February 2012 to January 2013. Preoperative internal lens signals were measured preoperatively. The depth of anterior chamber and anterior angles were measured using dual Scheimpflug anterior segment analyzer preoperatively and 1 month postoperatively. Preoperative and postoperative best-corrected visual acuities (BCVAs) were measured. The relationships between preoperative internal lens signal and the changes in BCVA or anterior angles were evaluated.
RESULTS
Internal lens signal and preoperative BCVA (log MAR) or preoperative anterior chamber depth were highly correlated (r = 0.287, p = 0.001 and r = -0.271, p = 0.004, respectively). Anterior angles increased 1 month after surgery compared with the preoperative values (p < 0.001). The amount of change between preoperative and postoperative anterior angles correlated with preoperative anterior angles (p < 0.001). However, no statistically significant correlation was observed between internal lens signal and preoperative anterior angles or postoperative BCVA. Internal lens signal correlated with changes in postoperative anterior angles (p < 0.001).
CONCLUSIONS
Internal lens signal correlated with preoperative visual acuity and may help evaluate the cataract severity quantitatively and objectively. Internal lens signal may aid in understanding the structure of anterior segments by predicting the lens volume. Knowing the effect of visual impairment due to cataracts and predicting visual improvement after cataract surgery is necessary.

Keyword

Cataract surgery; Dual Scheimpflug anterior segment analyzer; Internal lens signal; Visual acuity

MeSH Terms

Anterior Chamber
Cataract
Humans
Vision Disorders
Visual Acuity

Figure

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  Figure 1. Internal intensity of the lens using dual Scheimpflug camera. Internal intensity was decided as the value at the high-est intensity.

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  Figure 2. Internal lens signal and preoperative visual acuity, postoperative visual acuity, difference between preoperative visual acuity and postoperative visual acuity, or anterior chamber depth. Visual acuity was expressed as log MAR. AC = anterior chamber.

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  Figure 3. (A) Difference between preoperative and postoperative anterior chamber angle. (B) The relationship between preoperative anterior chamber angle and internal lens intensity. (C) The relationship between anterior chamber angles and the difference of anterior chamber angles. Preop = preoperative; Postop = postoperative. * Statistically significant by Wilcoxon rank test.

Reference

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