Influence of Biometric Data on Planning Strabismus Surgery. / Einfluss von biometrischen Daten auf die Planung der Augenmuskeloperation.

PURPOSE: To evaluate the influence of optical biometry data (axial eye length, anterior chamber depth) on planning strabismus surgery using a simulation software and partial least squares regression. METHODS: This retrospective study included patients who had undergone strabismus surgery in one eye involving only the horizontal eye muscles. Furthermore, optical biometry had been performed and the extent of strabismus had been measured pre- and postoperatively. In the next step the strabismus surgery was simulated (See++, RISC, Austria) with and without axial eye length data. In the last step, anatomical data of the eye were used and their influence on the postoperative extent of strabismus was evaluated using partial least squares regression and boot strapping. RESULTS: Of 97 patients, 92 were included in the analysis. In all cases the extent of strabismus was reduced by at least 25% and in 60% of the cases the reduction was at least 75%. Taking the axial eye length into account improved the simulation slightly (change of surgical planning: 0.30 mm, standard deviation 1.65 mm). DISCUSSION: The simulation model used showed that including the axial eye length is useful for strabismus surgery planning. However, the anterior chamber depth/axial eye length was found to have a significantly greater impact.

Variability in angle κ and its influence on higher-order aberrations in pseudophakic eyes.

PURPOSE: To observe the variability in angle κ in pseudophakic patients and assess its correlation with optical biometry measurements and higher-order aberrations (HOAs). SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Prospective case series. METHODS: This study included patients who had cataract surgery 3 months to 1 year before study recruitment. In all cases, Purkinje meter images were taken. In addition, partial coherence interferometry measurement (IOLMaster) of the axial intraocular lens (IOL) position was performed. In a subgroup of patients, an additional Hartmann-Shack sensor measurement was taken to assess HOAs (WASCA). RESULTS: This study comprised 395 eyes of 349 patients. The mean age of the 210 women and 139 men was 74.1 years ± 8.6 (SD) (range 44 to 91 years). The mean tilt (pupillary axis) and decentration were 3.9 ± 2.3 degrees (range 0.2 to 16.2 degrees) and 0.4 ± 0.2 mm (range 0.0 to 1.7 mm), respectively. The mean angle κ was 5.2 ± 2.6 degrees (range 0.3 to 13.9 degrees), and the mean orientation of this modulus was 189.5 ± 53.2 degrees (range 25.3 to 339.7 degrees). CONCLUSION: The variability in the angle κ was high.

Influence of the overall intraocular lens diameter on rotational stability.

PURPOSE: To evaluate the rotational stability of two intraocular lenses (IOLs) of similar design and material but with a difference of 1 mm in overall length. METHODS: In this prospective study patients with age-related cataract were included. An IOL with an overall diameter of 12 mm (ACR6 = small-diameter IOL) was compared to an IOL with an overall diameter of 13 mm (IDEA 613 XC = large-diameter IOL). RESULTS: In total, 60 patients were included in this study. Absolute rotation in the small- and large-diameter groups was 4.4° (SD: 4.0; range: 0.3-17.8) and 3.0° (SD: 2.4; range: 0.1-7.8), respectively. The differences between the two IOLs were not found to be statistically significant. CONCLUSION: The effect of the overall length of an IOL appears to have little impact on early rotation after cataract surgery.

Impact of bilateral cataract surgery on vision-related activity limitations.

PURPOSE: To evaluate patients' vision-related activity limitation before and after bilateral cataract surgery using the German version of the Catquest-9SF questionnaire. SETTING: Hanusch Hospital, Vienna, Austria, and Ophthalmic Clinic, Minden, Germany. DESIGN: Questionnaire development. METHODS: This prospective 2-center study included patients who were scheduled for bilateral cataract surgery and attended their preassessment appointment approximately 1 week before cataract surgery. All patients self-administered the Catquest-9SF at the preassessment session and a second time 3 months after cataract surgery. The questionnaire includes 9 items and is a revised short form of the Catquest, scored using Rasch analysis. The Catquest-9SF includes questions concerning vision-associated problems in everyday life, general satisfaction with vision, and difficulties performing activities. RESULTS: The study comprised 210 patients, 120 in Austria and 90 in Germany. The mean age of all patients was 74.1 years (range 41 to 92 years). Patients mostly had difficulties doing handwork (42%) or recognizing uneven surfaces (30%). Sixty percent of the patients in Austria and approximately 50% in Germany were very unsatisfied with their vision preoperatively. Postoperatively, all patients recognized a subjective improvement in their vision. CONCLUSIONS: Patients having bilateral cataract surgery achieved marked improvements in vision-related activity limitation and satisfaction with vision. A subset of patients with less vision-related activity limitation before surgery was satisfied with first-eye surgery only.