Three-dimensional evaluation of accommodating intraocular lens shift and alignment in vivo.
OBJECTIVE
To quantify 3-dimensionally the anterior segment geometry, biometry, and lens position and alignment in patients before and after implantation of the Crystalens-AO (Bausch & Lomb, Rochester, NY) accommodating intraocular lens (A-IOL).


METHODS
Prospective, observational study.


METHODS
Ten patients (20 eyes) with cataract before and after implantation of the Crystalens-AO A-IOL.


METHODS
Custom full anterior segment 3-dimensional (3-D) spectral optical coherence tomography (OCT) provided with quantification tools was used to image the cornea, iris, and natural lens preoperatively and intraocular lens postoperatively. Measurements were obtained under phenylephrine preoperatively and under natural viewing conditions and phenylephrine (for accommodative efforts ranging from 0 to 2.5 diopters [D]) and pilocarpine postoperatively.


METHODS
Three-dimensional quantitative anterior segment images, corneal geometry and power, anterior chamber depth (ACD), lens thickness, pupil diameter, A-IOL shift with accommodative effort or drug-induced accommodation, and A-IOL alignment.


RESULTS
Crystalline lens and IOLs were visualized and quantified 3-dimensionally. The average ACD were 2.64±0.24 and 3.65±0.35 mm preoperatively and postoperatively (relaxed state), respectively, and they were statistically significantly correlated (although their difference was not statistically correlated with lens thickness). The A-IOL did not shift systematically with accommodative effort, with 9 lenses moving forward and 11 lenses moving backward (under natural conditions). The average A-IOL shift under stimulated accommodation with pilocarpine was -0.02±0.20 mm. The greatest forward shift occurred bilaterally in 1 patient (-0.49 mm in the right eye and -0.52 mm in the left eye, under pilocarpine). The high right/left symmetry in the horizontal tilt of the crystalline lens is disrupted on IOL implantation. Accommodative IOLs tend to be slightly more vertically tilted than the crystalline lens, with increasing tendency with accommodative effort. Two subjects showed postoperative IOL tilts >9 degrees. Changes in pupillary diameter correlated with pilocarpine-induced A-IOL axial shift. Intermediate accommodative demands (1.25 D) elicited the greater shifts in axial A-IOL location and tilt and pupil diameter.


CONCLUSIONS
Quantitative 3-D anterior segment OCT allows full evaluation of the geometry of eyes implanted with A-IOLs preoperatively and postoperatively. High-resolution OCT measurements of the Crystalens 3-D positioning revealed small (and in many patients backward) A-IOL axial shifts with both natural or drug-induced accommodation, as well as tilt changes with respect to natural lens and accommodative effort.
Instituto de Óptica "Daza de Valdés," Consejo Superior de Investigaciones Científicas, Madrid, Spain. Electronic address: susana@io.cfmac.csic.es.
Susana
S
Marcos
Instituto de Óptica "Daza de Valdés," Consejo Superior de Investigaciones Científicas, Madrid, Spain.
Sergio
S
Ortiz
Instituto de Óptica "Daza de Valdés," Consejo Superior de Investigaciones Científicas, Madrid, Spain.
Pablo
P
Pérez-Merino
Instituto de Óptica "Daza de Valdés," Consejo Superior de Investigaciones Científicas, Madrid, Spain.
Judith
J
Birkenfeld
Fundación Jiménez Díaz, Madrid, Spain.
Sonia
S
Durán
Fundación Jiménez Díaz, Madrid, Spain.
Ignacio
I
Jiménez-Alfaro
D000065:Accommodation, Ocular / Q000187:drug effects / Q000502:physiology*; D000368:Aged; D000869:Anterior Eye Segment / Q000473:pathology*; D060437:Artificial Lens Implant Migration / Q000175:diagnosis*; D001699:Biometry; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008916:Miotics / Q000008:administration & dosage; D009184:Mydriatics / Q000008:administration & dosage; D018918:Phacoemulsification; D010656:Phenylephrine / Q000008:administration & dosage; D010862:Pilocarpine / Q000008:administration & dosage; D011184:Postoperative Period; D057234:Preoperative Period; D011446:Prospective Studies; D011474:Prosthesis Design; D011680:Pupil / Q000187:drug effects; D041623:Tomography, Optical Coherence
D008916:Miotics; D009184:Mydriatics; D010862:Pilocarpine; D010656:Phenylephrine