Good Uncorrected Distance Visual Acuity Research Articles

Corneal endothelial ring following the implantation of toric implantable collamer lenses with a central hole: a case report

BackgroundTo report a case of a corneal endothelial ring after toric implantable collamer lens (TICL, V4C) implantation in the right eye of a patient.Case presentationA 36-year-old woman with refractive errors of -8.00 DS/-2.00 DC * 8° in the right eye and − 6.50 DS/-1.75 DC * 177° in the left eye developed a corneal endothelial ring in the right eye on the first day after receiving TICLs implantation for treatment of high myopic astigmatism, which has not been previously reported as a complication of ICLs implantation. At 1 day postoperatively, the uncorrected distance visual acuity (UDVA) was 20/16, the intraocular pressure as measured by non-contact tonometry was 16.9 mmHg, and the vault as measured by anterior segment optical coherence tomography was 1238 μm. The eye was quiet and there was no unusual anterior chamber reaction. However, slit-lamp examination revealed an endothelial annular lesion of approximately 0.4 mm in diameter in the central part of the cornea, which was gray-white in color. The shape of the ring was the same as that of the central hole of the TICL. Specular microscopy showed that the mean endothelial cell density (ECD) of the ring significantly decreased to 1442 ± 263 cells/mm2, while the other part was still normal (2852 ± 103 cells/mm2). After 9 days of corticosteroid treatment and intense lubrication, the patient had a clear cornea, increased ECD (1532 ± 653 cells/mm2), and a good UDVA (20/16).ConclusionThis case suggests that a few hours after ICL V4C implantation, with a large vault, corneal displacement caused by an air puff would make the endothelium close to or even contact the ICL, producing a corneal endothelial ring. After ruling out various possible factors, we speculated that the endothelial ring was developed due to the non-contact tonometer air puff before slit-lamp evaluation, and this phenomenon was recorded by Corvis, which confirmed that the cornea could come in contact with the ICL due to gas shock. This “contact” may cause transient corneal endothelial damage.

Residual stromal bed thickness correlates with regression of myopia after LASIK.

PurposeThe purpose of this study was to evaluate the correlation between residual stromal bed thickness (hereinafter bed thickness) and regression of myopia after LASIK, taking into consideration the long-term outcomes.Subjects and methodsA total of 177 patients (309 eyes) and 41 patients (70 eyes) were retrospectively reviewed at 5 and 10 years after surgery, respectively. These patients were also continuously examined throughout the study. All patients underwent laser in situ keratomileusis (LASIK) for myopia in our clinic and scored at least 1.0 (0 logMAR) uncorrected distance visual acuity (UCVA) 1 month after surgery. Bonferroni–Dunn method and Student’s t-test were used for statistical analyses.ResultsCases with a refractive value (spherical equivalent) of less than −6.0 D (Group A) were compared to those with −6.1 D or higher (Group B). There was a statistically significant decrease in Group B UCVA of 0.04 logMAR and 0.12 logMAR at 5 and 10 years after surgery, respectively. With regard to the relationship between regression of myopia and bed thickness in the long-term, there was a significantly higher frequency of regression of myopia in cases with less than 350 μm bed thickness compared to those with 350 μm and more, in a surgical volume of more than −6.1 D (Group B).ConclusionThe present study indicates that bed thickness correlates with regression of myopia after LASIK and enough bed thickness is important to maintain good UCVA in the long-term.

Rotational stability and patient satisfaction after implantation of a new toric IOL.

To evaluate rotational stability, astigmatism correction, visual outcomes, and patient satisfaction after implantation of the toric intraocular lens (IOL) Torica-aA following cataract extraction over a 6-month follow-up period. This prospective observational study enrolled 40 eyes of 26 patients presenting with preexisting corneal astigmatism of 1.00 to 2.60 D. The rotational stability of the IOL was evaluated using retroillumination photographs taken within 24 hours after surgery and 1 week and 6 months postoperatively. Other main study outcomes were assessed 6 months postoperatively and included uncorrected and distance-corrected visual acuities, astigmatism correction, and patient satisfaction. Six months postoperatively, mean absolute IOL rotation was 1.99 ± 1.88° (range 0.10-7.40°) and secondary repositioning was not required. The IOL rotation was <3° in 85% of eyes, ≤5° in 94% of eyes, and <8° in 100% of eyes. Mean residual refractive cylinder was -0.57 ± 0.34 D. The magnitude of the J0 vector was significantly decreased postoperatively (p<0.0001). The mean J45 vector was close to zero preoperatively and postoperatively (p = 0.27). Mean monocular uncorrected distance visual acuity (UDVA) was 0.09 ± 0.12 logMAR and 97% of eyes achieved UDVA of 20/40 or better including 66% of eyes having 20/25 or better. The good UDVA resulted in high levels of spectacle independence and patient satisfaction. Implantation of the Torica-aA IOL was safe and effective in reducing low to moderate preexisting corneal astigmatism and provided good rotational stability and refractive outcomes, which led to a high degree of patient satisfaction.

Torische Intraokularlinsen: Eine nützliche Methode in der Korrektur des kornealen Astigmatismus

The aim of this stud was to assess clinical outcomes after implantation of a hydrophobic toric intraocular lens (IOL) in patients undergoing cataract surgery. 22 eyes (16 patients) with at least 0.8 diopter (D) of corneal astigmatism having routine cataract surgery were included. After marking the final axis of the IOL, phacoemulsification, implantation and alignment of a toric IOL was performed. Uncorrected distance visual acuity (UDVA), best corrected distance visual acuity (BDVA), manifest refraction, and keratometry were measured 5 to 19 months postoperatively. Individual patient satisfaction was also recorded. The cylinder axis of the toric IOL was determined at a slitlamp examination. The mean UDVA postoperatively was 0.3 logMAR±0.23 (SD) and was 0.3 logMAR or better in 63.6% of eyes. The mean refractive cylinder decreased significantly postoperatively, ranging from -3.3±1.5 D to -1.3±0.7 D. The mean absolute IOL misalignment was 7.5 degrees (range 0 to 21°). The good UDVA resulted in high levels of patient satisfaction. Implantation of a toric IOL during cataract surgery was an effective and safe method to manage corneal astigmatism in this series of patients.

Refractive accuracy with light-adjustable intraocular lenses

To evaluate efficacy, predictability, and stability of refractive treatments using light-adjustable intraocular lenses (IOLs). University Hospital Virgen de la Arrixaca, Murcia, Spain. Prospective nonrandomized clinical trial. Eyes with a light-adjustable IOL (LAL) were treated with spatial intensity profiles to correct refractive errors. The effective changes in refraction in the light-adjustable IOL after every treatment were estimated by subtracting those in the whole eye and the cornea, which were measured with a Hartmann-Shack sensor and a corneal topographer, respectively. The refractive changes in the whole eye and light-adjustable IOL, manifest refraction, and visual acuity were obtained after every light treatment and at the 3-, 6-, and 12-month follow-ups. The study enrolled 53 eyes (49 patients). Each tested light spatial pattern (5 spherical; 3 astigmatic) produced a different refractive change (P<.01). The combination of 2 light adjustments induced a maximum change in spherical power of the light-adjustable IOL of between -1.98 diopters (D) and +2.30 D and in astigmatism of up to -2.68 D with axis errors below 9 degrees. Intersubject variability (standard deviation) ranged between 0.10 D and 0.40 D. The 2 required lock-in procedures induced a small myopic shift (range +0.01 to +0.57 D) that depended on previous adjustments. Light-adjustable IOL implantation achieved accurate refractive outcomes (around emmetropia) with good uncorrected distance visual acuity, which remained stable over time. Further refinements in nomograms and in the treatment's protocol would improve the predictability of refractive and visual outcomes with these IOLs. No author has a financial or proprietary interest in any material or method mentioned.

Clinical outcomes after implantation of a new hydrophobic acrylic toric IOL during routine cataract surgery

To assess the clinical outcomes after implantation of a new hydrophobic acrylic toric intraocular lens (IOL) to correct preexisting corneal astigmatism in patients having routine cataract surgery. Four hospital eye clinics throughout Europe. Cohort study. This study included eyes with at least 0.75 diopter (D) of preexisting corneal astigmatism having routine cataract surgery. Phacoemulsification was performed followed by insertion and alignment of a Tecnis toric IOL. Patients were examined 4 to 8 weeks postoperatively; uncorrected distance visual acuity (UDVA), corrected distance visual acuity, manifest refraction, and keratometry were measured. Individual patient satisfaction with uncorrected vision and the surgeon's assessment of ease of handling and performance of the IOL were also documented. The cylinder axis of the toric IOL was determined by dilated slitlamp examination. The study enrolled 67 eyes of 60 patients. Four to 8 weeks postoperatively, the mean UDVA was 0.15 logMAR ± 0.17 (SD) and the UDVA was 20/40 or better in 88% of eyes. The mean refractive cylinder decreased significantly postoperatively, from -1.91 ± 1.07 D to -0.67 ± 0.54 D. No significant change in keratometric cylinder was observed. The mean absolute IOL misalignment from the intended axis was 3.4 degrees (range 0 to 12 degrees). The good UDVA resulted in high levels of patient satisfaction. Implantation of the new toric IOL was an effective, safe, and predictable method to manage corneal astigmatism in patients having routine cataract surgery.

Stereopsis after implantation of intraocular lens in patients under 40 years old with unilateral cataract.

To investigate the stereopsis after single focus intraocular lens (SIOL) implantation in patients aged <40 years with unilateral cataract. In total, 36 patients (36 eyes) were divided into emmetropia and myopia groups. Twenty seven subjects with good uncorrected distance visual acuity (UCDVA) after surgery were enrolled in the emmetropia group. The myopia group consisted of 9 subjects whose one eye had mild myopia postoperatively and the other was emmetropic or myopic. Visual acuity, distance and near stereoacuity were measured post-operatively. In the emmetropia group, uncorrected near visual acuity (UCNVA) did not differ significantly between eyes (t=1.87, P>0.05). The LogMAR UCNVA of the operated and fellow eyes were (0.71±0.12) and (-0.05±0.07, t = 28.4, P<0.001) respectively. Distance stereoacuity was 60"; the near stereoacuity with uncorrected visual acuity and BCNVA in the operated eyes were 200" and 30" respectively (Z=－4.121, P<0.001). In the myopia group, the BCDVA did not differ significantly between the operated and fellow eyes (t =-0.636, P>0.05). The UCNVA of the operated eyes (0.18±0.12) was significantly better compared with that of the fellow eyes (-0.04±0.10, t = 4.2252, P<0.001). The distance stereoacuity with uncorrected visual acuity and BCDVA in the operated eyes were 200" and 60" respectively (Z =-2.371, P<0.05). The near stereoacuity with uncorrected visual acuity was 50". For patients with unilateral cataract aged <40 years, stereopsis is closely associated with refractive status after IOL implantation. Near stereoacuity in emmetropic eyes can be improved with refraction, and that in mildly myopic eyes can be enhanced by leaving myopia uncorrected.

Performance of the Sulcoflex Piggyback Intraocular Lens in Pseudophakic Patients

To present our experience with a pseudophakic piggyback intraocular lens (IOL) (Sulcoflex; Rayner Intraocular Lenses Ltd) in five eyes of four patients. One patient desired increased spectacle independence after bilateral LASIK and refractive lens exchange with an accommodating IOL. The remaining three patients with residual refractive error desired increased spectacle independence following cataract surgery with a monofocal IOL. Four eyes received a multifocal Sulcoflex IOL and one eye received a toric Sulcoflex IOL. All patients achieved uncorrected distance visual acuity (UDVA) of 0.1 logMAR (Snellen 20/25) or better and those who received the multifocal Sulcoflex achieved uncorrected near visual acuity (UNVA) of N6 (Jaeger 4) or better. The Sulcoflex IOL may be a safe and effective method for enhancing the refractive outcome in pseudophakic eyes, providing good UDVA and UNVA when using the multifocal platform.

Residual Refractive Error and Visual Outcome After Cataract Surgery Using Spherical Versus Aspheric IOLs

to evaluate the effect of the residual refractive error on uncorrected distance visual acuity (UCVA) after cataract surgery using spherical versus aspheric intraocular lenses (IOL). there were 160 eyes of 125 patients who underwent uneventful cataract surgery included. Of these, 80 eyes received spherical IOLs and 80 eyes aspheric IOLs. Corneal astigmatism was measured preoperatively. Visual acuity, manifest refraction, scotopic pupil size, and spherical aberration were measured postoperatively and analyzed to determine the independent effects of postoperative astigmatism, sphere, spherical equivalent (SE), absolute value of SE, scotopic pupil size, and spherical aberration on postoperative UCVA. Eyes with postoperative astigmatism greater than 2.0 diopters were excluded. postoperative UCVA showed significant correlation with age, postoperative residual astigmatism, and absolute value of SE in eyes with spherical IOLs. However, postoperative UCVA showed significant correlation with only the absolute value of SE in the aspheric IOL group. eyes with spherical IOLs had good UCVA as long as the residual astigmatism was small. However, eyes with aspheric IOLs performed better in UCVA when the residual astigmatism was 1.5 diopters or greater.

Aspheric toric intraocular lenses for cataractous eyes: correction of corneal cylinder and spherical aberration

The corneas of many cataractous eyes have clinically significant astigmatism, and the corneas of almost all eyes have positive spherical aberration. The aspheric AcrySof® IQ Toric intraocular lens (IOL; Alcon Laboratories Inc., TX, USA) compensates for both corneal astigmatism and corneal spherical aberration. The aspheric profile of these IOLs was designed to match the profile of nontoric aspheric IOLs that had demonstrated clinically superior contrast sensitivity versus spherical IOLs. The platform of this toric IOL is rotationally stable and has a low repositioning rate. Patients with AcrySof Toric IOLs had low residual cylinder, good uncorrected distance visual acuity and high rates of spectacle independence, which may be associated with reduced lifetime patient costs and increased patient satisfaction. Aspheric IQ Toric IOLs should be as safe and efficacious as their spherical toric IOL predecessors and should also offer an added visual quality benefit owing to the new aspheric design.