A clinical case of replacing an opacified intraocular lens in avitreal eye

Purpose. Using a clinical example, to analyze the possible causes of opacity of the Hydro-4 Aspheric IOL (Rumex, Great Britain). Materials and methods. Patient K., 32 years old, underwent the surgery for tractional retinal detachment in both eyes, which arose against the background of proliferative diabetic retinopathy of the retina. A history of type 1 diabetes mellitus from the age of 9. The visual acuity of both eyes before surgery was 0.03 n/k. Microinvasive (25G) vitrectomy with silicone oil tamponade of the vitreous cavity was performed. The second stage of surgical treatment is the removal of silicone oil from the vitreous cavity and phacoemulsification of cataract with partial excision of the posterior lens capsule with IOL implantation into the capsule bag of both eyes. A Hydro-4 Aspheric IOL (Rumex, UK) was implanted in the right eye, and Aspira-aAy (HumanOptic AG, Germany) – in the left one. After 3 months, on examination, attention was drawn to the diffuse opacity of the IOL of the right eye. The visual acuity was 0.01 n/k. The IOL replacement technique was as follows. Viscoelastic was injected into the anterior chamber and into the capsule bag through corneal paracentesis at 10 and 2 o'clock. The lens was dislocated into the anterior chamber and cut in half with vitreal scissors. The cut parts of the IOL were removed through a 2.2 mm tunnel at 12 o'clock. The Tecnis lens (AMO, USA) was chosen for implantation. Results and discussion. There was an increase in uncorrected visual acuity up to 0.4. There were no intra- and postoperative complications such as hemorrhagic, inflammatory, and also any from the cornea. The question remains open why, with the same tactics of the first two stages of surgical treatment of both eyes and implantation of lenses made of hydrophilic acrylic, only one IOL became cloudy. Accounting for the materials from which the IOL is made, which lens model is better to prefer to this day remains an urgent and unresolved problem for ophthalmic surgeons. Conclusion. The presence of a concomitant diabetes mellitus in the patient could influence the development of opacification of the hydrophilic acrylic IOL. Key words: IOL opacity, hydrophilic acrylic, IOL explantation, avitria.

Does Every Calculation Formula Fit for All Types of Intraocular Lenses? Optimization of Constants for Tecnis ZA9003 and ZCB00 Is Necessary

Background and Objectives: To evaluate the performance of intraocular lenses (IOLs) using power calculation formulas on different types of IOL. Materials and Methods: 120 eyes and four IOL types (BioLine Yellow Accurate Aspheric IOL (i-Medical), TECNIS ZCB00, TECNIS ZA9003 (Johnson & Johnson) (3-piece IOL) and Softec HD (Lenstec)) were analyzed. The performance of Haigis, Barret Universal II and SKR-II formulas were compared between IOL types. The mean prediction error (ME) and mean absolute prediction error (MAE) were analyzed. Results: The overall percentage of eyes predicted within ±0.25 diopters (D) was 40.8% for Barret; 39.2% Haigis and 31.7% for SRK-II. Barret and Haigis had a significantly lower MAE than SRK-II (p < 0.05). The results differed among IOL types. The largest portion of eyes predicted within ±0.25 D was with the Barret formula in ZCB00 (33.3%) and ZA9003 (43.3%). Haigis was the most accurate in Softec HD (50%) and SRK-II in Biolline Yellow IOL (50%). ZCB00 showed a clinically significant hypermetropic ME compared to other IOLs. Conclusions: In general, Barret formulas had the best performance as a universal formula. However, the formula should be chosen according to the type of IOL in order to obtain the best results. Constant optimizations are necessary for the Tecnis IOL ZCB00 and ZA9003, as all of the analyzed formulas achieved a clinically significant poor performance in this type of IOL. ZCB00 also showed a hypermetropic shift in ME in all the formulas.

Objective Optical Quality in Eyes with Customized Selection of Aspheric Intraocular Lens Implantation

Backgroud To compare the postoperative optical quality in eyes with customized selection and random selection of aspheric intraocular lens (IOL) implantation. Methods A prospective, nonrandomized study was implemented in adult cataract patients who underwent unilateral phacoemulsification with aspheric IOL implantation. Patients were allocated into two treatment groups: a customized group and a control group. In the customized group, the aspheric IOL selection was based on the corneal spherical aberration to enable the postoperative target ocular spherical aberration closest to zero; in the control group, the aspheric IOLs were chosen using a random strategy. Primary outcome measurements included the following objective optical quality assessments: higher-order aberrations obtained by a Hartmann-shack aberrometer at 4mm and 6mm pupil diameters; objective scatter index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR) and a simulated contrast visual acuity—optical quality analysis system value (OV) obtained by a double-pass system with a 4-mm aperture. Subjective visual acuity was measured as secondary outcome. All the patients were followed up for 3 months. Results Eighty-four patients in the customized group and 78 patients in the control group were evaluated. There was no significant difference in postoperative visual acuity between the two groups (P>0.05). Significantly less ocular higher-order aberrations were shown in the customized group (P<0.05). No significant difference was shown in OSI, MTF cut-off, SR and OV between the two groups (P>0.05). Conclusions Although customized selection of aspheric IOL implantation showed less postoperative ocular aberrations, it performed similarly to random selection of aspheric IOL implantation in terms of postoperative visual acuity, simulated contrast visual acuity, intraocular scatter, modulation transfer function and Strehl ratio.

Objective Optical Quality in Eyes with Customized Selection of Aspheric Intraocular Lens Implantation

Backgroud To compare the postoperative optical quality in eyes with customized selection and random selection of aspheric intraocular lens (IOL) implantation. Methods A prospective, nonrandomized study was implemented in adult cataract patients who underwent unilateral phacoemulsification with aspheric IOL implantation. Patients were allocated into two treatment groups: a customized group and a control group. In the customized group, the aspheric IOL selection was based on the corneal spherical aberration to enable the postoperative target ocular spherical aberration closest to zero; in the control group, the aspheric IOLs were chosen using a random strategy. Primary outcome measurements included the following objective optical quality assessments: higher-order aberrations obtained by a Hartmann-shack aberrometer at 4mm and 6mm pupil diameters; objective scatter index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR) and a simulated contrast visual acuity—optical quality analysis system value (OV) obtained by a double-pass system with a 4-mm aperture. Subjective visual acuity was measured as secondary outcome. All the patients were followed up for 3 months. Results Eighty-four patients in the customized group and 78 patients in the control group were evaluated. There was no significant difference in postoperative visual acuity between the two groups (P>0.05). Significantly less ocular higher-order aberrations were shown in the customized group (P<0.05). No significant difference was shown in OSI, MTF cut-off, SR and OV between the two groups (P>0.05). Conclusions Although customized selection of aspheric IOL implantation showed less postoperative ocular aberrations, it performed similarly to random selection of aspheric IOL implantation in terms of postoperative visual acuity, simulated contrast visual acuity, intraocular scatter, modulation transfer function and Strehl ratio.

Objective Optical Quality in Eyes with Customized Selection of Aspheric Intraocular Lens Implantation

Backgroud To improve the aspheric intraocular lens (IOL) selection strategy in cataract surgery. Methods A prospective, nonrandomized study was implemented in adult cataract patients who underwent unilateral phacoemulsification with aspheric IOL implantation. Patients were allocated into two treatment groups: a customized group and a control group. In the customized group, the aspheric IOL selection was based on the corneal spherical aberration to enable the postoperative target ocular spherical aberration closest to zero; in the control group, the aspheric IOLs were chosen using a random strategy. Primary outcome measurements included the following objective optical quality assessments: higher-order aberrations obtained by a Hartmann-shack aberrometer at 4mm and 6mm pupil diameters; objective scatter index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR) and a simulated contrast visual acuity—optical quality analysis system value (OV) obtained by a double-pass system with a 4-mm aperture. Subjective visual acuity was measured as secondary outcome. All the patients were followed up for 3 months. Results Eighty-four patients in the customized group and 78 patients in the control group were evaluated. There was no significant difference in postoperative visual acuity between the two groups (P>0.05). Significantly less ocular higher-order aberrations were shown in the customized group (P<0.05). No significant difference was shown in OSI, MTF cut-off, SR and OV between the two groups (P>0.05). Conclusions Although customized selection of aspheric IOL implantation showed less postoperative ocular aberrations, it performed similarly to random selection of aspheric IOL implantation in terms of postoperative visual acuity, simulated contrast visual acuity, intraocular scatter, modulation transfer function and Strehl ratio.

True rotational stability of a single-piece hydrophobic intraocular lens

BackgroundTo evaluate rotation and its influencing factors of an aspheric one-piece hydrophobic acrylic intraocular lens (IOL) Vivinex XY1 during 6 months after operation.MethodsIn this institutional trial, 122 eyes of 66 patients were implanted with a non-toric aspheric IOL Vivinex XY1 (Hoya Corporation, Tokyo, Japan). IOL alignment was assessed at the end of surgery, 1 hour, 1 week, 1 month and 6 months after implantation. Confounding factors such as axial length, presence of anterior fibrosis and randomised implantation in four different intended axes (0°, 45°, 90°, 135°) were evaluated. Decentration and tilt were measured using a Purkinje metre.ResultsAssessment of rotational stability was possible for 103 of 122 implanted IOLs 6 months after eye surgery. The median absolute rotation was 1.1° (range: 0°–5°). Rotation was significantly increased within the first hour after operation compared with later time-points (p<0.001). No correlation was found with axial length and rotation (Spearman’s r=0.048, p=0.63). No significant difference was observed regarding different implantation axes (p=0.75). Rotation was not influenced by the presence of anterior fibrosis (p=0.98).ConclusionAssessing the true IOL position at the end of surgery is crucial for the evaluation of rotational stability of IOLs. No IOL rotation exceeding 5° could be detected 6 months after surgery.

Comparison of Two Toric IOLs with Different Haptic Design: Optical Quality after 1 Year

Background. The purpose of this prospective, randomised study was to interocularly compare the visual performance after implantation of two different toric IOLs with different haptic design. Methods. 59 subjects with corneal astigmatism greater than 1.25 diopter (D) were implanted with an AT TORBI 709M IOL (Carl Zeiss Meditec AG) in one eye and with a Tecnis toric aspheric IOL (Abbot Medical Optics) in the other eye. Observation procedure was performed 12 months postoperatively. Main outcome measures included uncorrected distance visual acuity (UDVA), manifest refraction, IOL rotation, and IOL position. Results. Mean UCDVA was 0.04 ± 0.14 logMAR for AT TORBI eyes and 0.06 ± 0.15 logMAR for Tecnis eyes (p=0.3). The postoperative spherical equivalent values were significantly lower in the AT TORBI group. Mean toric IOL axis rotation was 3.0 ± 2.26 degrees for AT TORBI eyes and 3.27 ± 2.37 for Tecnis eyes (p=0.5). The mean vertical IOL tilt and vertical decentration values measured with the Visante OCT were significantly larger in the AT TORBI group (p<0.05). Conclusions. Both the Tecnis and the AT TORBI toric IOLs successfully reduced ocular astigmatism. Emmetropia could be better achieved with the AT TORBI IOL, whereas the Tecnis showed better positional stability. This trial is registered with ICMJE NCT03371576.

Evaluierung der postoperativen Astigmatismuskorrektur und der postoperativen Rotationsstabilität zweier torischer Intraokularlinsen

Zusammenfassung Hintergrund Im Rahmen dieser retrospektiven Studie wurden 2 verschiedene torische Intraokularlinsen auf Rotationsstabilität und das refraktive Ergebnis miteinander verglichen. Methoden Es handelt sich um eine Analyse von 41 Patientenaugen, die an der Augenabteilung im Krankenhaus Hietzing in den Jahren 2010 bis 2013 operiert wurden. Der korneale Astigmatismus lag über 1,5 Dioptrien (dpt). Bei den implantierten Linsen handelte es sich um die Alcon AcrySof IQ Toric IOL und die Abbott Tecnis Toric Aspheric IOL. Die Ermittlung der Topografie und die Messung der Aberrationen erfolgten mit dem HOYA iTrace™. Die Visusbestimmung erfolgte mit ETDRS-Tafeln. Die gemessenen Abbildungsfehler des untersuchten Auges wurden mit Zernike-Koeffizienten dargestellt. Ergebnisse Die Rotation in der Alcon-Gruppe war 4,92 ± 4,10° (MW ± SD), in der Abbott-Gruppe 4,31 ± 4,59°. Es zeigte sich hierbei kein signifikanter Unterschied zwischen den beiden torischen Intraokularlinsen, die Rotationsstabilität ist mit anderen Studien vergleichbar. Die refraktive Astigmatismuskorrektur wurde mittels einer Power-Vektoren-Analyse veranschaulicht und zeigte ähnliche Ergebnisse mit eindeutigem Erfolg der Astigmatismuskorrektur. Bei der Alcon IOL zeigte sich ein Restastigmatismus von 0,85 ± 0,48 dpt, bei der Abbott Tecnis IOL war er 1,09 ± 0,66. Der Unterschied ist nicht signifikant. Bei den Abbildungsfehlern (Strehl-Zahl) zeigte sich im Vergleich kein signifikanter Unterschied. Schlussfolgerung Die Implantation einer torischen Intraokularlinse ist mittlerweile bei regulärem Astigmatismus ein sinnvolles Angebot, das dem Patienten nicht vorenthalten werden sollte. Es zeigte sich hierbei kein signifikanter Unterschied zwischen den beiden torischen Intraokularlinsen.

Aspheric Intraocular Lenses Implantation for Cataract Patients with Extreme Myopia

Objective. To evaluate the postoperative visual quality of cataract patients with extreme myopia after implantation of aspheric intraocular lenses (IOLs). Methods. Thirty-three eyes were enrolled in this prospectivestudy. Eighteen eyes with an axial length longer than 28 mm were included in the extreme myopia group, and the other 15 eyes were included in the nonextreme myopia group. Phacoemulsification and aspheric IOL implantation were performed. Six months after cataract surgery, best-corrected visual acuity (BCVA), contrast sensitivity, and wavefront aberrations were measured, and subjective visual quality was assessed. Results. The BCVA improved significantly after surgery for both groups, and patients in the nonextreme myopia group achieved better postoperative BCVA due to better retinal status of the eyes. The evaluation of contrast sensitivity without glare was the same in both groups, whereas patients in the nonextreme myopia group performed better at intermediate spatial frequencies under glare conditions. The two groups did not show a significant difference in high-order aberrations. With regard to subjective visual quality, the composite scores of both groups did not differ significantly. Conclusions. Aspheric IOLs provided good visual outcomes in cataract patients with extreme myopia. These patients should undergo careful evaluation to determine the maculopathy severity level before surgery.