PURPOSE OF REVIEWThere are several different approaches to handling regular and irregular astigmatism during cataract surgery, but still much debate on which solutions are most effective given unique ...patient circumstances. In this review, we examine recent literature and studies to highlight some of the most effective ways to plan preoperatively, manage regular and irregular astigmatism during cataract surgery, as well as managing postoperative complications.
RECENT FINDINGSRecent developments in technology have provided increased courses of action for astigmatism management during cataract surgery. Additional options of toric IOLs with presbyopic platforms, light adjustable lenses, intraocular pinhole lenses, online technological tools and platforms, wavefront or topographic laser technology, and phototherapeutic keratectomy are all effective solutions to managing regular and irregular astigmatism. In this review, we will explore optimal approaches for unique situations.
SUMMARYWith increased technology, research, and methods, correcting regular and irregular astigmatism during cataract surgery is achievable in most patients. With in-depth preoperative planning, analysis of patient-specific factors, and a tailored approach, surgeons can obtain excellent uncorrected vision for patients.
To determine whether there is a difference in how much residual astigmatism impacts uncorrected distance visual acuity (UDVA) after multifocal versus monofocal intraocular lens (IOL) implantation.
...Database study.
Retrospective data review.
An online toric IOL back-calculator allows users to input preoperative toric planning information and postoperative IOL orientation and refractive results. These data are used to determine the optimal orientation of the IOL to minimize residual refractive astigmatism. Aggregate data were extracted from this calculator to investigate factors associated with UDVA and relative magnitudes of residual astigmatic refractive error up to 2.5 diopters (D) after implantation of toric IOLs.
Of 1919 pertinent records (455 multifocal toric IOLs and 1464 monofocal toric IOLs), a statistically significant difference by refractive cylinder category (P < .01) and a statistically significant difference by IOL type (P = .042) were noted. This difference was mostly driven by patients with residual refractive astigmatism of 1.5 D. The mean change in UDVA was 0.16 logarithm of the minimum angle of resolution per 1.0 D of astigmatism. Evaluating a more homogenous dataset with the same monofocal and multifocal IOL design, there was a statistically significant effect of refractive cylinder (P < .01) but no significant effect of IOL type (monofocal or multifocal, P = .45). The differences in UDVA at different refractive cylinder values was not statistically significantly different by orientation of the current astigmatism (P = .28).
Residual astigmatism after toric IOL implantation impacts visual acuity similarly in patients who had multifocal and monofocal toric IOL implantation.
PURPOSETo evaluate the safety and effectiveness of the LipiFlow System compared to the iHeat Warm Compress (WC) for adults with meibomian gland dysfunction (MGD).
METHODSThis was a non-significant ...risk, prospective, open-label, randomized, crossover multicenter clinical trial. One hundred thirty-nine subjects were randomized between LipiFlow (n=69) and WC control (n=70). Subjects in the LipiFlow group received a 12-minute LipiFlow treatment and were reexamined at 1 day, 2 weeks and 4 weeks. Control subjects received a 5-minute iHeat treatment with instructions to perform the same treatment daily for 2 weeks. At 2 weeks, they crossed over (LipiFlow Crossover) and received the LipiFlow treatment. Effectiveness parametersmeibomian gland (MG) assessment, tear break-up time (TBUT) and dry eye symptoms. Safety parametersadverse events, ocular health exam, ocular surface staining, intraocular pressure, visual acuity and discomfort.
RESULTSLipiFlow resulted in significant improvement (P < 0.05) in MG secretion at 2 and 4 weeks (mean ± standard deviation at baseline = 6.3 ± 3.5; 2 weeks = 14.3 ± 8.7; 4 weeks = 16.7 ± 8.7); and TBUT at 2 and 4 weeks(at baseline = 5.5 ± 2.9; 2 weeks = 6.9 ± 5.0; 4 weeks = 7.4 ± 5.5). There was no significant change in MG secretion or TBUT in the control group. LipiFlow resulted in a greater significant reduction in dry eye symptoms than the iHeat WC. The crossover group demonstrated similar significant improvement 2 weeks post-treatment with the LipiFlow. There was no significant difference between groups in the incidence of non-serious, device-related adverse events.
CONCLUSIONThe LipiFlow System was significantly more effective than iHeat WC. These results support its safety and effectiveness in the treatment of MGD and dry eye symptoms.
To evaluate the rotational stability of the three monofocal toric intraocular lenses (IOLs) via data from an online toric IOL back-calculator.
A retrospective data review of an online toric IOL ...back-calculator, which allows users to input preoperative toric planning information, postoperative lens orientation, and subjective refraction. Inputted data were used to determine the optimal orientation of the toric IOL to minimize residual refractive astigmatism. Aggregate data from 3/11/2019 to 3/10/2020 were extracted and validated. Only data with ≥0.5D of residual refractive astigmatism were used in the study. Pre-operative intended IOL orientation and post-operative IOL orientation were used to calculate IOL rotation.
After validation, 5397 entries were determined to represent patient eyes, of which 3238 represented the three monofocal IOLs evaluated. The rate of rotation for AcrySof, TECNIS, and enVista Toric IOLs was 72.7%, 83.4%, and 83.0%, respectively, and location only significantly impacted TECNIS IOLs. The magnitude of rotation for rotated IOLs was similar for all models and was significantly more for IOLs initially placed in the oblique axis. All IOL models tended to rotate in a counterclockwise direction (53.2%, 73.0%, 69.7%, respectively; p<0.05), and the tendency was greater for IOLs initially located horizontally.
The AcrySof IQ Toric IOL was more rotationally stable than both the TECNIS and enVista Toric IOLs; there was no significant difference in rotational stability of the latter two.
To assess outcomes of Descemet stripping endothelial keratoplasty (DSEK) in eyes with custom artificial iris (CAI) implantation.
This is a retrospective, interventional, consecutive, surgical case ...series of patients who underwent DSEK after CAI implantation between 2010 and 2021 at 2 referral centers. Primary safety measures were loss of corrected distance visual acuity (CDVA), increase in intraocular pressure (IOP), development or progression of glaucoma, and intraoperative and postoperative complications. Efficacy measures were graft survival at year 1 and improvement in cosmesis at postoperative month 3. In general, measures were compared between baseline and postoperative year 1 while any complication was reported for the full follow-up period.
Thirty-nine eyes of 39 patients were identified. 64.1% of eyes had acquired aniridia from trauma. The mean follow-up interval was 27.7 months (range 12.2-117.4). Median CDVA improved from logMAR 1.0 to 0.7 at year 1 (P = 0.0047). At the final follow-up, permanent loss of CDVA occurred in 25.6% of eyes, of which 90% was due to glaucoma. The most common postoperative complication was IOP elevation (66.7% of eyes). Graft survival at postoperative year 1 was 82.0% (95% confidence interval, 66.3-91.4). Secondary graft failure occurred in 28.2% of eyes at a mean duration of 39.7 months (SD 27.9 months) after DSEK. Cosmesis improved among 87.2% of eyes at postoperative month 3.
DSEK is an effective procedure for addressing corneal edema in eyes with a CAI, but a majority develop elevated IOP and graft survival is shorter than in eyes without a CAI.
To analyze intraocular lens (IOL) orientation data from an online toric back-calculator (astigmatismfix.com) for determining if differences were apparent by lens type.
A retrospective review of ...astigmatismfix.com toric back-calculations that included IOL identification and intended orientation axis.
Of 12,812 total validated calculation records, 8,229 included intended orientation and lens identification data. Of the latter, 5,674 calculations (69%) involved lenses oriented 5° or more from their intended position. Using estimated toric lens usage data, the percentage of lenses with orientation ≥5° from intended was 0.89% overall, but the percentage varied significantly between specific toric lens brands (
<0.05). The percentage of back-calculations related to lenses that were not oriented as intended was also statistically significantly different by lens brand (
<0.05). When IOLs were misoriented, they were significantly more likely to be misoriented in a counterclockwise direction (
<0.05). This was found to be due to a bias toward counterclockwise orientation observed with one specific brand, a bias that was not observed with the other three brands analyzed here.
The percentage of eyes with lens orientation ≥5° from intended in the Toric Results Analyzer data set was <1% of toric IOLs in general, with the relative percentage of Tecnis
Toric IOLs significantly higher than AcrySof
Toric IOLs. Both of these had higher rates than the Staar
Toric and Trulign
Toric lenses, with the availability of higher Tecnis and AcrySof cylinder powers a likely contributing factor. The AcrySof Toric IOL appears to be less likely than the Tecnis Toric IOL to cause residual astigmatism as a result of misorientation. The Tecnis Toric IOL appears more likely to be misoriented in a counterclockwise direction; no such bias was observed with the AcrySof Toric, the Trulign
Toric, or the Staar Toric IOLs.
To evaluate factors associated with residual astigmatism after toric intraocular lens implantation based on data from an online toric intraocular lens (IOL) back-calculator.
This was a retrospective ...data review of an online toric IOL back-calculator, which allows users to input preoperative toric planning information and postoperative lens orientation and refractive results. These data were used to determine the optimal orientation of the IOL to minimize residual refractive astigmatism. Aggregate data were extracted from this calculator to investigate factors associated with relative magnitudes of residual astigmatic refractive error after implantation of toric IOLs.
A total of 3,159 validated records with an average reported postoperative refractive astigmatism of 1.85 diopters (D) were analyzed; 566 included data allowing calculation of surgically induced astigmatism. The relative magnitude of reported residual astigmatism appeared similar whether a femtosecond laser system was used or not. Significant differences relative to the use of intraoperative aberrometry were observed, as were differences by toric calculator. Higher measured surgically induced astigmatism was most associated with higher levels of reported residual astigmatism. A significant potential decrease in the mean refractive astigmatism was expected with IOL reorientation; in 1,416 cases (44.8%), the expected residual refractive astigmatism after lens reorientation was less than 0.50 D, with a mean reduction of 56% ± 31%.
When present after cataract surgery, higher levels of residual refractive astigmatism were most associated with large differences in measured preoperative to postoperative keratometry. To a lesser degree, intraoperative aberrometry was associated with lower levels. J Refract Surg. 2018;34(6):366-371..
February consultation #3 Hardten, David R.
Journal of cataract and refractive surgery,
February 2019, 2019-02-00, Letnik:
45, Številka:
2
Journal Article
To evaluate safety and efficacy of a custom-manufactured artificial iris device (CustomFlex Artificial Iris; HumanOptics AG) for the treatment of congenital and acquired iris defects.
Multicenter, ...prospective, unmasked, nonrandomized, interventional clinical trial.
Patients with photophobia, sensitivity secondary to partial or complete congenital or acquired iris defects, or both.
Eyes were implanted from November 26, 2013, to December 1, 2017, with a custom, foldable artificial iris by 1 of 4 different surgical techniques. Patients were evaluated 1 day, 1 week, and 1, 3, 6, and 12 months after surgery. At each examination, slit-lamp findings, intraocular pressure, implant position, subjective visual symptoms, and complications were recorded. Corrected distance visual acuity (CDVA) and endothelial cell density (ECD) were measured at 3, 6, or 12 months as additional safety evaluations. The 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) was used to assess health-related quality of life affected by vision. The Global Aesthetic Improvement Scale was used to assess cosmetic results.
Photosensitivity, glare, visual symptoms, NEI VFQ-25 score, Global Aesthetic Improvement Scale rating, prosthesis-related adverse events, intraocular lens (IOL)-related adverse events, and surgery-related adverse events 12 months after surgery.
At the 12-month postoperative examination, a 59.7% reduction in marked to severe daytime light sensitivity (P < 0.0001), a 41.5% reduction in marked to severe nighttime light sensitivity (P < 0.0001), a 53.1% reduction in marked to severe daytime glare (P < 0.0001), and a 48.5% reduction in severe nighttime glare (P < 0.0001) were found. A 15.4-point improvement (P < 0.0001) in the NEI VFQ-25 total score was found, and 93.8% of patients reported an improvement in cosmesis as measured by the Global Aesthetic Improvement Scale 12 months after surgery. No loss of CDVA of > 2 lines related to the device was found. Median ECD loss was 5.3% at 6 months after surgery and 7.2% at 12 months after surgery.
The artificial iris surpassed all key safety end points for adverse events related to the device, IOL, or implant surgery and met all key efficacy end points, including decreased light and glare sensitivity, improved health-related quality of life, and satisfaction with cosmesis. The device is safe and effective for the treatment of symptoms and an unacceptable cosmetic appearance created by congenital or acquired iris defects.
To assess the relationship between axial length (AL) and intraocular lens (IOL) rotation among eyes receiving a toric IOL and subsequently entered into an online toric back-calculator database.
...Retrospective analysis of data collected online
astigmatismfix.com, a freely available online toric back-calculator where surgeons enter pre- and post-operative information to help manage residual postoperative astigmatism. Included records were deemed valid with entry of AL and IOL orientation between January 2017 and March 2019. Rotation was determined by a difference of ≥5° between pre-operative intended IOL orientation and actual post-operative IOL orientation. Frequency and magnitude of rotation are presented with means and associated standard deviation (SD). Linear regression models of this association are presented.
Records of 6752 eyes were included in the analysis, of which 74.8% were determined to have a rotated IOL. The magnitude of rotation increased with each millimeter (mm) increase in AL with a mean rotation of 13.3° (SD: 12.8°) for eyes with AL 20-20.9 mm and a maximum mean rotation of 30.6° (SD: 30.3°) among eyes with AL 29-29.9 mm. General linear modeling demonstrated a significant association (
<0.0001) with a parameter estimate of 1.19 (standard error: 0.159) and
of 0.0083.
Analysis from an online database indicates that toric IOLs inserted into eyes with longer AL are more likely to rotate and to rotate more degrees from the target axis. The findings from this study are clinically relevant for surgeons implanting toric IOLs.
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