Vector Analysis, Rotational Stability, and Visual Outcome After Implantation of a New Aspheric Toric IOL.
OBJECTIVE
To evaluate vector analysis, rotational stability, and refractive and visual outcome of a new toric intraocular lens (IOL) for correction of preexisting corneal astigmatism during routine cataract surgery.


METHODS
In this prospective, interventional case series, 30 toric, aspheric Bi-Flex T toric IOLs (Medicontur Medical Engineering Ltd., Inc., Zsámbék, Hungary) were implanted in 20 consecutive patients with topographic corneal astigmatism between 1.50 and 4.00 diopters (D) and evaluated within the first year after implantation. Appropriate IOL-toric alignment was facilitated by combined imaging/eye tracking technology. Postoperative evaluation included refraction and uncorrected and corrected distance visual acuities (UDVA, CDVA). For each visit, photodocumentation in retroillumination was performed to evaluate toric alignment and potential toric IOL rotation. Vector analysis of refractive astigmatism was performed using the Alpins method.


RESULTS
At 12 months postoperatively, a reduction of the refractive astigmatism from 1.93±0.90 D (range: 0.50 to 4.00 D) to 0.28±0.61 D (range: 0.00 to 1.50 D) could be found, with patients achieving a mean UDVA of 0.06±0.16 logMAR (range: -0.18 to 0.40 logMAR; Snellen 20/20). Intraoperative to 12-month postoperative comparison of IOL axis alignment showed low levels of rotation (0.2°±2.41°; range: +4° to -5°). Vector analysis showed target induced astigmatism of 0.60 D @180°, surgically induced astigmatism of 0.80 D @177°, correction index of 1.02±0.25, and a difference vector of 0.30 D @82°.


CONCLUSIONS
Implantation of the new Bi-Flex T IOL was a safe, stable, and effective method to correct preexisting regular corneal astigmatism during cataract surgery.
Alexander
A
Bachernegg
Theresa
T
Rückl
Clemens
C
Strohmaier
Gerlinde
G
Jell
Günther
G
Grabner
Alois K
AK
Dexl
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000150:complications; D002386:Cataract / Q000150:complications; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification; D011446:Prospective Studies; D011474:Prosthesis Design; D019591:Pseudophakia / Q000503:physiopathology* / Q000523:psychology; D011788:Quality of Life / Q000523:psychology; D015348:Vision, Binocular / Q000502:physiology*; D014792:Visual Acuity / Q000502:physiology*; D055815:Young Adult