Keratoconus: exploring fundamentals and future perspectives - a comprehensive systematic review.

Background: New developments in artificial intelligence, particularly with promising results in early detection and management of keratoconus, have favorably altered the natural history of the disease over the last few decades. Features of artificial intelligence in different machine such as anterior segment optical coherence tomography, and femtosecond laser technique have improved safety, precision, effectiveness, and predictability of treatment modalities of keratoconus (from contact lenses to keratoplasty techniques). These options ingrained in artificial intelligence are already underway and allow ophthalmologist to approach disease in the most non-invasive way. Objectives: This study comprehensively describes all of the treatment modalities of keratoconus considering machine learning strategies. Design: A multidimensional comprehensive systematic narrative review. Data sources and methods: A comprehensive search was done in the five main electronic databases (PubMed, Scopus, Web of Science, Embase, and Cochrane), without language and time or type of study restrictions. Afterward, eligible articles were selected by screening the titles and abstracts based on main mesh keywords. For potentially eligible articles, the full text was also reviewed. Results: Artificial intelligence demonstrates promise in keratoconus diagnosis and clinical management, spanning early detection (especially in subclinical cases), preoperative screening, postoperative ectasia prediction after keratorefractive surgery, and guiding surgical decisions. The majority of studies employed a solitary machine learning algorithm, whereas minor studies assessed multiple algorithms that evaluated the association of various keratoconus staging and management strategies. Last but not least, AI has proven effective in guiding the implantation of intracorneal ring segments in keratoconus corneas and predicting surgical outcomes. Conclusion: The efficient and widespread clinical translation of machine learning models in keratoconus management is a crucial goal of potential future approaches to better visual performance in keratoconus patients. Trial registration: The article has been registered through PROSPERO, an international database of prospectively registered systematic reviews, with the ID: CRD42022319338.

Keratoconus: from fundamentals to future Artificial intelligence has changed how we treat the eye disease keratoconus in recent years. This study examines the many keratoconus therapies available, including surgery and contact lens wear, and how artificial intelligence can improve the safety and accuracy of these procedures. We combed through numerous papers to locate this data. To achieve the best outcomes, several parameters and methods should be evaluated. According to the study, some elements from eye scans are more useful than others. The idea behind using artificial intelligence is to help patients see better and treat keratoconus more effectively.

Dislocation force of scleral flange-fixated intraocular lens haptics.

PURPOSE: To measure the dislocation forces in relation to haptic material, flange size and needle used. SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Laboratory Investigation. METHODS, MAIN OUTCOME MEASURES: 30 G (gauge) thin wall and 27 G standard needles were used for a 2 mm tangential scleral tunnel in combination with different PVDF (polyvinylidene fluoride) and PMMA (polymethylmethacrylate haptics). Flanges were created by heating 1 mm of the haptic end, non-forceps assisted in PVDF and forceps assisted in PMMA haptics. The dislocation force was measured in non-preserved cadaver sclera using a tensiometer device. RESULTS: PVDF flanges achieved were of a mushroom-like shape and PMMA flanges were of a conic shape. For 30 G needle tunnels the dislocation forces for PVDF and PMMA haptic flanges were 1.58 ± 0.68 N (n = 10) and 0.70 ± 0.14 N (n = 9) (p = 0.003) respectively. For 27 G needle tunnels the dislocation forces for PVDF and PMMA haptic flanges were 0.31 ± 0.35 N (n = 3) and 0.0 N (n = 4), respectively. The flange size correlated with the occurring dislocation force in experiments with 30 G needle tunnels (r = 0.92), when flanges were bigger than 384 micrometres. CONCLUSIONS: The highest dislocation forces were found for PVDF haptic flanges and their characteristic mushroom-like shape for 30 G thin wall needle scleral tunnels. Forceps assisted flange creation in PMMA haptics did not compensate the disadvantage of PMMA haptics with their characteristic conic shape flange.

Quality assurance via telephone interviews after cataract surgery: An explorative study.

INTRODUCTION: Cataract surgery is a relatively safe procedure with satisfactory postoperative results in most patients. However, in rare cases severe complications can occur shortly after the intervention. Therefore, patients are advised to undergo an ophthalmological examination postoperatively, which should be performed as soon as possible in case of emergencies. However, exactly when these follow-up visits should take place is still discussed. A time- and cost-saving alternative to this could be short-term postoperative telemedical approaches. The aim of this study was to analyze patient complaints as well as satisfaction with and the best timepoint to perform telephone calls after cataract surgery. METHODS: Patients scheduled for cataract surgery received a telephone call on the surgery day or the day after (study group) during which they were asked about complaints or additional examination visits. Patients without telephone calls served as control group. All patients had a follow-up visit one week after the intervention during which a questionnaire was filled out and the study group was asked about their satisfaction with the telephone calls. RESULTS: 181 patients were recruited in this study. Ocular surface problems were the most common postoperative symptom. More than 80% of the patients were very satisfied with the telephone calls, with patients being contacted on the day of surgery being more calmed than those called on the next day. No difference in additional and planned follow-up visits was found between the study and the control group (P > .40). Postoperative patient complaints (Phi 0.372, P < .001) and additional prescribed therapy (Phi 0.480, P < .001) were moderately associated with additional visits. CONCLUSION: Satisfaction with telephone reviews shortly after cataract surgery was very high and contacting patients on the evening of the day of the procedure could be a time- and cost-saving alternative to short-term in-house follow-up visits.

Influence of sutureless scleral fixation techniques with 3-piece IOLs on dislocation force.

PURPOSE: To compare four different secondary IOL fixation techniques regarding the least required force to dislocate a scleral fixated 3-piece IOL in human corneoscleral donor tissue (CST). DESIGN: Experimental Laboratory investigation METHODS: The least required dislocation force (LRDF) of four different secondary IOL fixation techniques, namely the techniques using transscleral tunnels (TT, as described by Scharioth), glued haptics (GH, Argawa), flanged haptics (FH, Yamane) and bent haptic ends (BH, Behera/Bolz) were investigated using 40 three-piece IOLs (Sensar AR40) fixated to human scleral tissue. The main outcome of the study, dislocation force between different techniques, was measured with a tensiometer. RESULTS: The dislocation force needed to dislocate the haptics was highest with the FH technique and was significantly higher than with all the other techniques (GH vs FH: -1.02±0.02 N, p<0.001; TT vs FH: -1.08±0.21 N, p<0.001; BH vs FH: -1.00±0.25 N, p=0.044). There was no significant difference regarding the dislocation force between the other techniques (GH vs TT (-0.06±0.100 N, p=0.988), GH vs BH (-0.02±0.03 N, p=0.60), TT vs BH (-0.08±0.04 N, p=1.000). CONCLUSIONS: The flange haptic technique as described by Yamane proved to be the strongest form of secondary IOL fixation regarding dislocation force in this in vitro study. The other fixation techniques showed significantly less resistance to axial traction.

Rotational stability and capsular bag performance of a hydrophobic acrylic open-loop single-piece intraocular lens.

PURPOSE: To evaluate the rotational stability and capsular bag performance of a blue light-absorbing hydrophobic acrylic open-loop single-piece intraocular lens (IOL) with a blast-finished anchor wing haptic design during the first 6 postoperative months. METHODS: In this prospective clinical study, patients with age-related cataract and potential postoperative corrected distance visual acuity (CDVA) of 0.2 logMAR or better were included. The patients received a non-toric hydrophobic acrylic single-piece IOL with an axis mark (YST0.00; Nidek Co. Ltd, Japan). Surgeries were video-taped. Retroillumination images were acquired 1 h, 1 week and 6 months postoperatively. Rotational stability was assessed by precise image overlay. At 6 months, Purkinje meter measurements were performed to evaluate tilt and decentration. RESULTS: In total, 100 eyes of 77 patients were included in the analysis. Mean absolute rotation was 2.1 ± 1.7° (median 1.7, range: 0-7.9) at 6 months (1 h - 6 months postoperatively). IOL rotation was ≤3° and ≤6° in 74 (74%) and 98 (98%) eyes, respectively. Mean absolute IOL rotation from the end of surgery to 6 months was 2.5 ± 2.2° (median 2.3, range: 0-15.6; n = 78). Mean tilt (pupillary axis) and decentration were 4.1 ± 1.9° (median 4.0, range: 0.5-8.2) and 0.35 ± 0.17 mm (median 0.32, range: 0.06-0.91) respectively (n = 84). Postoperatively, 98 (98%) eyes achieved a CDVA of 0.2 logMAR or better, 95 (95%) of ≤0.1 and 81 (81%) of ≤0.0. CONCLUSIONS: This hydrophobic acrylic single-piece IOL showed an excellent rotational stability and capsular bag position with low tilt and decentration values.

Foveal-Sparing ILM Peeling with ILM Flap Transposition over the Macular Hole for Repair of Full-Thickness Macular Holes.

BACKGROUND: Full-thickness macular holes, defined as full-thickness defects of the fovea, lead to central scotoma and deterioration of vision. Apart from peeling of the internal limiting membrane (ILM), ILM flap techniques have been reported to have potential in improving results in macular hole surgery. In addition, foveal-sparing ILM peeling gives a high macular hole closure rate and improvement in postoperative visual acuity. The aim of this study was to examine outcomes in a cohort of patients with full-thickness macular holes that underwent vitrectomy with foveal-sparing ILM peeling and transposition of an ILM flap over the macular hole. METHODS: This retrospective study included patients scheduled for pars plana vitrectomy with foveal-sparing ILM peeling, combined with ILM flap transposition over the macular hole, for macular hole repair. All patients received a gas tamponade with 20% sulphur hexafluoride and were encouraged to undergo postoperative face-down positioning for 48 hours after surgery. Optical coherence tomography (OCT) imaging of the macula and distance-corrected visual acuity (DCVA) were performed before and 3 months after surgery. RESULTS: In total, 42 eyes of 42 patients were included in this study. Leaving a broad area of residual ILM at the foveal rim led to a high risk of failure in macular hole closure, while leaving a narrow zone of residual ILM at the foveal rim resulted in high macular hole closure rates (97% type 1 closure and 3% type 2 closure), with a median improvement of DCVA of 4 lines [interquartile range (IQR): 3 to 6] among pseudophakic and 3.5 lines (IQR: 2 to 5) among phakic patients. CONCLUSIONS: A combination of foveal-sparing ILM peeling with ILM flap techniques was shown to be a safe and effective surgical option for patients with full-thickness macular holes, resulting in a high macular hole closure rate and improvement in visual acuity in the majority of patients.

Online intraocular lens calculation.

PURPOSE OF REVIEW: To showcase the majority of online intraocular lens (IOL) calculation tools and highlight some of their characteristics. RECENT FINDINGS: Online tools are available for preoperative and postoperative IOL-related calculations, including IOL power and toricity selection for standard patients, patients who underwent prior refractive surgery, keratoconus, limbal relaxing incisions for astigmatism management, realignment of a misplaced or rotated toric IOL, surgical induced astigmatism (SIA), formulae comparison, and other tools. SUMMARY: As there are new online developments and technology is advancing rapidly, we hope that this review will assist ophthalmologists in becoming acquainted with a large variety of online tools.

Attaining the optimal flange technique for transscleral capsular bag stabilization using iris hooks.

PURPOSE: To investigate the flange properties of different iris hooks. SETTING: Vienna Institute for Research in Ocular Surgery (VIROS), Hanusch Hospital, Vienna, Austria. DESIGN: Laboratory study. METHODS: The flanging properties of 4 different iris hooks made from polypropylene (PP), elastic polymer (EP), and nylon were investigated with different heating distances and both with and without forceps gripping. The maximum diameter of the flanges was measured, and the shape of the flanges was evaluated. RESULTS: Although both nylon and EP iris hooks had too small flange diameters for intrascleral fixation, PP iris hooks had a sufficient flange diameter (>330 µm) and mushroom-like shape. Furthermore, in PP hooks, heating distance was directly proportional to flange diameter. CONCLUSIONS: The findings of this study suggest that only PP iris hooks are suitable for flanged intrascleral fixation, which is off-label, to secure adequate fixation.

Repeatability of biometry in patients with meibomian gland dysfunction before and after vectored thermal pulsation therapy: A randomized, controlled trial.

PURPOSE: To evaluate the effect of vectored thermal pulsation therapy (VTPT) on the repeatability of biometry readings of two different optical biometers in patients with meibomian gland dysfunction (MGD). METHODS: Patients affected by MGD were included in this prospective, randomized, controlled, investigator-masked study. One eye was randomized to VTPT (LipiFlow®, Johnson & Johnson), and the contralateral eye served as a control. Three visits were scheduled at baseline, 2 weeks and 3 months after the treatment. The main outcome parameter of the study was the repeatability of three calculations of emmetropic intraocular lens power (EIOLP) at the 3 months visit as compared to baseline using an optical biometer (IOLMaster® 700, Carl Zeiss Meditec AG). Repeatability of different keratometry values obtained by the optical biometer and a Placido-disc topographer (MS-39®, CSO) served as secondary outcome parameters. RESULTS: Twenty-nine patients were included in the final analysis. While tear film parameters improved in the study eyes, there were no significant differences regarding the repeatability of three EIOLP measurements between baseline and 3-months-visit in both eyes (p > 0.05) and keratometry measurements in both the optical biometer and the Placido-disc topographer. Remarkably, throughout all study visits, there were some outliers regarding the repeatability of measurements. CONCLUSION: While both devices showed high repeatability regarding EIOLP and keratometry, future studies are needed to detect high-risk patients for poor repeatability.

Reducing ophthalmic surgical waste through electronic instructions for use: a multisociety position paper.

Every ophthalmic surgical supply, including intraocular lenses (IOLs), IOL cartridges, and ophthalmic viscosurgical device syringes, is packaged with instructions for use (IFU). These pamphlets are printed in multiple languages and, in the case of an IOL, significantly increase the size and weight of the packaging. To eliminate this significant and unnecessary source of waste, we recommend that manufacturers move to Quick Response codes that link to online electronic IFU (e-IFU) as a sensible alternative. In addition to reducing carbon emissions and manufacturing costs, e-IFU can be updated more easily and accessed by surgeons in the clinic, where IOL models and powers are selected. Varying and inconsistent IFU requirements between different countries are a barrier to wider adoption of e-IFU by the ophthalmic surgical industry. Regulatory agencies in every country should allow and encourage e-IFU. This position paper has been endorsed by the 3 major societies that sponsor EyeSustain, a consortium of global societies dedicated to advancing sustainability in ophthalmology.

Differences Between Keratometry and Total Keratometry Measurements in a Large Dataset Obtained With a Modern Swept Source Optical Coherence Tomography Biometer.

PURPOSE: This study aimed to explore the concept of total keratometry (TK) by analyzing extensive international datasets representing diverse ethnic backgrounds. The primary objective was to quantify the disparities between traditional keratometry (K) and TK values in normal eyes and assess their impact on intraocular lens (IOL) power calculations using various formulas. DESIGN: Retrospective multicenter intra-instrument reliability analysis. METHODS: The study involved the analysis of biometry data collected from ten international centers across Europe, the United States, and Asia. Corneal power was expressed as equivalent power and astigmatic vector components for both K and TK values. The study assessed the influence of these differences on IOL power calculations using different formulas. The results were analyzed and plotted using Bland-Altman and double angle plots. RESULTS: The study encompassed a total of 116,982 measurements from 57,862 right eyes and 59,120 left eyes. The analysis revealed a high level of agreement between K and TK values, with 93.98% of eyes exhibiting an absolute difference of 0.25 D or less. Astigmatism vector differences exceeding 0.25 D and 0.50 D were observed in 39.43% and 1.08% of eyes, respectively. CONCLUSIONS: This large-scale study underscores the similarity between mean K and TK values in healthy eyes, with rare clinical implications for IOL power calculation. Noteworthy differences were observed in astigmatism values between K and TK. Future investigations should delve into the practicality of TK values for astigmatism correction and their implications for surgical outcomes.

Occurrence of Corneal Staining after Cataract Surgery with and without Chitosan-N-Acetylcysteine Eye Drops.

INTRODUCTION: The objective of this study was to evaluate the prevalence of ocular surface damage assessed by corneal staining scores right after cataract surgery and whether it can be prevented using chitosan-N-acetylcysteine (C-NAC) eye drops. METHODS: We included patients scheduled for routine cataract surgery. Each patient was randomly assigned to one of three groups. Patients in group 1 underwent routine cataract surgery with no additional eye drops. In group 2, patients received C-NAC eye drops after cataract surgery, and in group 3, C-NAC was applied both before and after surgery. Both groups continued the treatment once daily for 4 days. Ocular surface alteration was assessed using the National Eye Institute (NEI) score, and the visual analog scale (VAS) was used to evaluate subjective complaints. RESULTS: Thirty-six patients were included in the final analyses. One hour after cataract surgery, a statistically significant increase in corneal fluorescein staining was observed in all groups, which decreased again after 1 week. There was no significant difference between the groups 1 h after cataract surgery, though a tendency toward lower NEI scores was observed during this time point in group 3. DISCUSSION: Cataract surgery induced ocular surface staining and subjective complaints after 1 h. However, the increase in VAS score was small and probably not clinically relevant. The application of perioperative C-NAC eye drops did reduce the rate of corneal staining after cataract surgery in a clinically relevant manner.

Keratoconus Diagnosis: From Fundamentals to Artificial Intelligence: A Systematic Narrative Review.

The remarkable recent advances in managing keratoconus, the most common corneal ectasia, encouraged researchers to conduct further studies on the disease. Despite the abundance of information about keratoconus, debates persist regarding the detection of mild cases. Early detection plays a crucial role in facilitating less invasive treatments. This review encompasses corneal data ranging from the basic sciences to the application of artificial intelligence in keratoconus patients. Diagnostic systems utilize automated decision trees, support vector machines, and various types of neural networks, incorporating input from various corneal imaging equipment. Although the integration of artificial intelligence techniques into corneal imaging devices may take time, their popularity in clinical practice is increasing. Most of the studies reviewed herein demonstrate a high discriminatory power between normal and keratoconus cases, with a relatively lower discriminatory power for subclinical keratoconus.

Comparison of corneal aberrations from anterior segment swept source OCT versus Placido-topography combined spectral domain OCT in cataract patients.

BACKGROUND: To comprehensively evaluate the agreement of component corneal aberrations from the newly updated wavefront analysis software of a swept-source optical coherence tomographer (SS-OCT) and a referential Placido-topography combined OCT device in elderly cataract patients. METHODS: Retrospective study including 103 eyes from 103 elderly patients scheduled for cataract surgery that were measured on the same day with a SS-OCT (Heidelberg Engineering, Germany) device and a Placido-topography combined OCT device (CSO, Italy). Anterior, total, and posterior corneal wavefront aberrations were evaluated for their mean differences and limits of agreement (LoA) via Bland-Altman plots. Vector analysis was additionally employed to compare corneal astigmatism measurements in dioptric vector space. RESULTS: Mean differences of all corneal aberrometric parameters did not exceed 0.05 µm. Total corneal aberrations were not significantly different from 0 except for vertical coma (- 0.04 µm; P = 0.003), spherical aberration (- 0.01 µm, P < 0.001), and root mean square (RMS) higher-order aberration (HOA) (0.03 µm, P = 0.04). The 95% LoA for total corneal aberration parameters between both devices were - 0.46 to 0.42 µm for horizontal astigmatism, - 0.37 to 0.41 µm for oblique astigmatism, - 0.19 to 0.17 µm for oblique trefoil, - 0.33 to 0.25 µm for vertical coma, - 0.20 to 0.22 µm for horizontal coma, - 0.22 to 0.20 µm for horizontal trefoil, - 0.11 to 0.08 µm for spherical aberration, and - 0.22 to 0.28 µm for RMS HOA. Vector analysis revealed no statistically significant mean differences for anterior, total, and posterior corneal astigmatism in dioptric vector space. CONCLUSION: In eyes undergoing cataract surgery with a regular elderly cornea, corneal wavefront analysis from the SS-OCT device showed functional equivalency to the reference device. Nevertheless, clinically relevant higher order aberration parameters should be interpreted with caution for surgical decision-making.

Immediate sequential vs delayed sequential bilateral cataract surgery: systematic review and meta-analysis.

The main aim of this systematic review and meta-analysis was to evaluate the safety and efficacy profile of immediate sequential bilateral cataract surgery (ISBCS) compared with delayed sequential bilateral cataract surgery (DSBCS). MEDLINE Ovid, EMBASE, and CENTRAL databases were searched. Outcome measures were postoperative visual acuity, postoperative spherical equivalent (refractive outcome), endophthalmitis, corneal edema, pseudophakic macular edema, and posterior capsule rupture (PCR). 13 articles met criteria for final inclusion. A total of 11 068 622 participants (18 802 043 eyes) were included. No statistically significant differences between ISBCS and DSBCS were identified in all the postoperative outcomes evaluated. However, a higher risk for PCR was identified in the ISBCS group from the pooled analysis of nonrandomized studies (risk ratio, 1.34, 95% CI, 1.08-1.67, P = .0081). In our view, the ISBCS approach has an acceptable safety-efficacy profile, comparable with DSBCS. Future investigations are warranted, with a focus on the analysis of risk factors for surgical complications, patient-reported outcome-measures, and cost effectiveness.

Effect of Treatment with Topical Azithromycin or Oral Doxycycline on Tear Film Thickness in Patients with Meibomian Gland Dysfunction: A Randomized Controlled Trial.

Purpose: This prospective, randomized, observer-masked, parallel-group study aimed to compare the effect of topical azithromycin and oral doxycycline on tear film thickness (TFT) and signs and symptoms of ocular surface disease (OSD) in patients with meibomian gland dysfunction (MGD). Methods: Patients were randomized to either receive topical azithromycin or oral doxycycline. After a baseline visit, three follow-up visits at intervals of 2 weeks were scheduled. Main outcome of the study was change in TFT as measured with ultrahigh resolution optical coherence tomography. Results: Twenty patients were included in the analysis. TFT significantly increased in both groups (P = 0.028 vs. baseline) with no difference between the groups (P = 0.096). As secondary outcomes, ocular surface disease index (OSDI) score and composite signs of OSD significantly decreased in both groups (P = 0.023 for OSDI and P = 0.016 for OSD signs vs. baseline). While eye-related adverse events (AEs) occurred more frequently in the azithromycin group, systemic AEs were more common in the doxycycline group. Conclusions: Both treatments improved signs and symptoms of OSD in patients with MGD with no difference between the groups. Due to the higher frequency of systemic side effects of doxycycline, azithromycin eye drops seem to be an alternative with comparable efficacy. Clinical Trial Registration number: NCT03162497.

Assessing the astigmatism-reducing effect of toric intraocular lenses in eyes with low astigmatism: randomized masked bilateral comparison.

PURPOSE: To evaluate the astigmatism-reducing effect of toric intraocular lenses (IOLs) for low amounts of corneal astigmatism. SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Randomized, masked, controlled trial with bilateral comparison. METHODS: Patients scheduled for bilateral cataract surgery and a corneal astigmatism in both eyes between 0.75 diopters (D) and 1.5 D were included in this study. The first eye was randomized to receive either a toric IOL or a nontoric IOL, and the contralateral eye received the other type of IOL. At the follow-up visits, optical biometry, corneal measurements with tomography and topography, autorefraction, subjective refraction, corrected and uncorrected distance visual acuity (CDVA/UDVA) with ETDRS charts and a questionnaire were performed. RESULTS: 58 eyes were included in the study. Postoperative median UDVA was 0.00 (logMAR) in the toric eyes and 0.10 in the nontoric eyes ( P = .03). The median CDVA was 0.00 in both groups ( P = .60). Median residual astigmatism determined by subjective refraction and autorefraction in the toric eyes was 0.25 D and 0.50 D, respectively ( P = .04), and 0.50 D and 1.00 D in the nontoric eyes, respectively ( P < .001). CONCLUSIONS: The use of a toric IOL appears to be appropriate from a threshold value of approximately 0.75 D preoperative corneal astigmatism. Further studies in a larger patient population are needed to confirm these results.

Size variability and fitting of 30-gauge thin-wall needles and 3-piece intraocular lens haptics for the flanged intrascleral fixation technique.

PURPOSE: To assess the diameter of different 30-gauge thin-wall needles and 3-piece intraocular lens (IOL) haptics readily used for the flanged-haptic intrascleral fixation technique. SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Laboratory investigation. METHODS: 5 30-gauge thin-wall needles and 5 3-piece IOLs were assessed. An upright light microscopy was used for measurements. The inner and outer diameters of the needles and the end thickness of the haptics were analyzed and compared for haptic fitting into the needle. RESULTS: Among the needles, the inner diameter of the T-lab needle was significantly wider compared with all the others (mean 209.3 ± 8.0 µm, P < .001), followed by TSK (194.8 ± 5.0 µm), MST (194.7 ± 5.8 µm), Sterimedix (187.5 ± 9.0 µm) and significantly narrower Meso-relle (mean 178.7 ± 7.0 µm, P < .05). The outer diameter of the T-lab needle was significantly larger of all (mean 316.0 ± 2.0 µm, P < .001). Concerning the IOLs, the AvanseePreset Kowa's haptic was significantly thinner (mean 127.2 ± 0.7 µm) than all the others, such as the TecnisZA900 Johnson & Johnson (143.5 ± 3.1 µm), the CTLucia202 Zeiss (143.8 ± 1.3 µm), and the AcrysofMA60AC Alcon (143.9 ± 1.4 µm). The only haptic that was thicker than all the others assessed was that of SensarAR40 Johnson & Johnson (170.7 ± 1.7 µm, P < .001). CONCLUSIONS: Most of the analyzed haptics would fit into most of the measured needles, with the exception of the Sensar AR40 in combination with the Meso-relle or Sterimedix needles. The combination of a larger needle lumen and a thinner haptic could result in more ease of insertion during surgery. If the dimensions of the needle and IOL haptics used are unknown, we recommend trying insertion before beginning surgery.

Surgeons need to know more about intraocular lens design for accurate power calculation.

Improvement in biometry and formulas has raised the bar for accurate intraocular lens (IOL) power calculation. However, when we look closely at the performance of a specific IOL model, we often find that the prediction error varies with the implant power. This phenomenon has no explanation other than that the optic design of the IOL has shifted over the power range, thereby disrupting the assumptions of the calculations. By this report, we call the industry to be more transparent and disclose the basic information about the IOL design that is important for accurate IOL power calculation. The relevant information concerns the refractive index, the central optic thickness, the anterior and posterior curvature radii, the toricity location, the spherical aberration, and haptic angulation. The goal is to predict possible shifts in principal planes or IOL position over the power range causing a refractive surprise if not corrected for.

Rotational stability of a new toric intraocular lens with an advanced optical profile.

PURPOSE: To examine the rotational stability of a new toric intraocular lens (IOL), the TECNIS Eyhance Toric II, over a course of 3 months. SETTING: Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria. DESIGN: Prospective unmasked single-center study. METHODS: 50 eyes of 50 patients with cataract and regular corneal astigmatism ≥0.75 diopters (D) were included. The TECNIS Eyhance Toric II IOL was implanted in 1 eye of each study patient. Images of the alignment axis of the IOL were taken intraoperatively, as well as at 1 hour, 1 week, and 3 months postoperatively. For the measurement of toric IOL rotation, images were superimposed on the basis of ocular landmarks. Uncorrected and corrected distance (4 m) and intermediate (66 cm) visual acuities were assessed at the 3-month visit. RESULTS: There was no significant difference in the rotational position between the intraoperative and 3 month timepoints, with a mean rotation of 1.34 ± 1.46 degrees, in 27 examined eyes. ( P = 0.313). No patients had to undergo repositioning of the toric IOL. A significant reduction of refractive cylinder occurred from preoperatively 1.8 ± 1.1 to 0.40 ± 0.42 D at the 3-month visit ( P = .001; n = 43). The corrected distance visual acuity improved significantly from 0.28 ± 0.16 logMAR preoperatively to -0.01 ± 0.13 logMAR at 3 months postoperatively ( P = .001; n = 43). CONCLUSIONS: The TECNIS Eyhance Toric II showed a good visual performance with no significant rotation over a course of 3 months and, therefore, an excellent rotational stability. The intraocular lens showed a good safety profile with no adverse events.