Use Of Toric Intraocular Lens Research Articles

Toric Intraocular Lenses for the Management of Corneal Astigmatism at the Time of Cataract Surgery

Methods This audit was conducted in a UK ophthalmology department and included 48 eyes of 42 patients. Surgery was performed during 2019 in patients with 2.50 diopters (D) or more corneal astigmatism. Anterior keratometry readings were used to determine the toric IOL power. Vector analysis using the Alpins method was used to assess changes in astigmatism pre to postoperatively. Results There were 18 right and 26 left eyes included. In terms of gender, 61% of patients were female and 39% were male. The mean (±standard deviation (SD)) age was 70 (±11) years. The mean (±SD) axial length, K1, K2, and delta K was 23.55 (±1.4) mm, 42.71 (±1.39) D, 45.78 (±1.60) D, and 3.01 (±0.89) D, respectively. Postoperatively, the median spherical, cylinder, and spherical equivalent refraction was 0.00 D, −1.00 D, and 0.00 D, respectively. Postoperatively, 41% of the eyes had ≤0.50 D of spectacle astigmatism and 80% had ≤1.00 D. No patient required a secondary procedure to reposition the IOL from rotation. In vector analysis with the use of polar diagrams, there was a tendency for overcorrection of with-the-rule astigmatism and undercorrection of against-the-rule astigmatism. Conclusions Significant reductions in astigmatism can be achieved with the use of toric IOLs in patients undergoing cataract surgery. Further improvements may be possible with surgeon-specific determination of their surgically induced astigmatism and flattening effect from the main corneal incision. Furthermore, the use of an optical biometer that directly measures the posterior corneal curvature and permits automatic toric IOL power determination with modern formulas avoiding the need for manual data entry may reduce the risk of human error and improve visual and refractive outcomes.

Refractive Status in Eyes Implanted with Toric and Nontoric Intraocular Lenses during Combined Cataract Surgery and Microhook Ab Interno Trabeculotomy.

Purpose To compare the refractive status between eyes implanted with toric and nontoric intraocular lenses (IOLs) during combined cataract surgery and microhook ab interno trabeculotomy (μLOT), a minimally invasive glaucoma surgery (MIGS). Methods Twenty eyes of 20 patients who had open-angle glaucoma, cataract, and preexisting regular corneal astigmatism exceeding 1.5 diopters (D) and underwent combined μLOT and phacoemulsification were recruited retrospectively. Ten eyes were implanted with a toric IOL and 10 eyes with a nontoric IOL. The primary outcomes were the uncorrected visual acuity (UCVA) and refractive cylinder at 3 months postoperatively. Results The mean UCVA of the toric IOL group (logarithm of the minimum angle of resolution (logMAR), 0.23 ± 0.25) was significantly better than that of the nontoric IOL group (logMAR, 0.45 ± 0.26) at 3 months postoperatively (p < 0.05). The mean absolute residual refractive cylinder of the nontoric IOL group (2.25 ± 0.62 D) was significantly greater than that of the toric IOL group (1.30 ± 0.68 D) (p < 0.05). Postoperatively, 60% of eyes in the toric IOL group and 10% in the nontoric IOL group had an absolute refractive astigmatism level of 1.5 D or less. Surgically induced astigmatism (0.77 ± 0.43 D for toric group and 0.60 ± 0.32 D for nontoric group) and IOP reduction (33.9 ± 15.6% for toric group and 29.4 ± 11.7% for nontoric group) were not different between groups. Conclusions Use of toric IOL during combined cataract surgery and μLOT is possible and better than not, but physician should prevent their patient of persisting residual astigmatism. The study was registered at https://www.umin.ac.jp/, and the clinical trial accession number is https://clinicaltrials.gov/ct2/show/UMIN000043141.

Toric IOL in Combined DMEK and Cataract Surgery.

IntroductionDescemet membrane endothelial keratoplasty (DMEK) is the current gold standard surgical procedure to treat Fuchs endothelial keratoplasty. Cataract removal and intraocular lens (IOL) implantation can be safely combined with this corneal procedure. This paper presents a case series in which a toric intraocular lens (IOL) was used in combined DMEK and cataract surgery to correct corneal astigmatism.MethodsFour eyes that had a toric IOL implanted in combined cataract and DMEK surgery were included.ResultsThere was a reduction in manifest refractive cylinder and improvement in uncorrected and best-corrected vision in all cases.DiscussionSurgeons may consider the use of toric IOLs in selected cases of combined DMEK and cataract surgery for Fuchs endothelial dystrophy.

Corneal astigmatism in patients with various ophthalmic pathologies

To analyze the prevalence, magnitude of corneal astigmatism, anatomical parameters of the eye and age of patients with the condition, as well as to assess the prospects of its correction with intraocular lenses (IOLs). The study involved a retrospective analysis of initial biometric data of 128 379 patients (256 630 eyes) referred to the S.N. Fedorov NMRC «MNTK «EYE MICROSURGERY» research center in the years 2013 to 2018. The patients previously operated for cataract were examined 6 months after surgery. In 5 years, corneal astigmatism of over 1.0 D was diagnosed in 66 610 (25.96%) eyes. Among them, low astigmatism was observed in 86.30% of cases, with-the-rule - in 56.10%, compound - in 78.72%, and astigmatism combined with myopic refraction - in 61.48%. More severe astigmatism is characterized by thinner cornea and lens (p<0.05). Cataract surgery with implantation of toric IOLs was performed only on 2.56% of eyes. The average age of the operated patients was 68.42±13.3. Patients with implanted toric IOLs had 23% better uncorrected visual acuity (UCVA), and 15% better corrected visual acuity compared with outcomes of spherical IOL implantation. Corneal astigmatism of more than 1.0 D was observed in 25.96% of examined subjects. Patients with corneal astigmatism apply for cataract surgery 10 years earlier, when they are still in the working age, due to inability to engage in professional activities; in most cases, those patients are female. Astigmatism of up to 0.75 D is more common on the right dominant eye, of 2.0 D and higher - on the left. The correlation coefficients determined for study data indicate a barely noticeable relationship between biometric parameters and the degree of astigmatism. The use of toric intraocular lenses provides a 2-fold increase in uncorrected visual acuity compared to spherical IOLs.

Effect of Toric Intraocular Lens Implantation on Visual Acuity and Astigmatism Status in Eyes Treated With Microhook Ab Interno Trabeculotomy

Use of toric intraocular lenses is a reasonable option for better visual outcomes when a combined minimally invasive glaucoma surgery (MIGS) and cataract surgery is performed in eyes with corneal astigmatism. To assess the efficacy of toric intraocular lenses (IOLs) in combined cataract and MIGS, visual and refractive outcomes were compared between eyes implanted with nontoric and toric IOLs during microhook ab interno trabeculotomy triple procedures. Glaucomatous eyes with preexisting corneal astigmatism exceeding -1.5 D implanted with nontoric (n=10) or toric (n=10) IOLs were evaluated retrospectively. The uncorrected visual acuity (UCVA) and refractive astigmatism preoperatively and 3 months postoperatively were compared. Preoperatively, the groups had similar logarithm of the minimum angle of resolution (logMAR) UCVAs and refractive astigmatism. Postoperatively, the logMAR UCVA (toric, 0.07±0.07; nontoric, 0.33±0.30; P=0.0020) was significantly better and the refractive astigmatism (toric, -0.63±0.56 D; nontoric, -1.53±0.74 D; P=0.0110) significantly less in the toric group. The toric group had postoperative improvements in the logMAR UCVA (-0.58, P=0.0039) and refractive astigmatism (+1.45 D, P=0.0195). Vector analyses showed the postoperative centroid magnitude of refractive astigmatism was less in the toric group (0.23 D at 83 degrees) than the nontoric group (1.03 D at 178 degrees). Postoperatively, 70% of eyes in the toric group had 1.0 D or less refractive astigmatism compared with 10% in the nontoric group. Surgically induced astigmatism (nontoric group, 0.62 D at 10 degrees; toric group, 0.50 D at 113 degrees) and intraocular pressure reduction (22% in both groups) did not differ between groups. Better visual outcomes may be achieved with toric IOLs when a combined MIGS/cataract surgery is performed in eyes with corneal astigmatism.

Astigmatism Management with Intraocular Lens Surgery

Corneal astigmatism is common. More than 40% of patients undergoing cataract surgery have 1 diopter (D) power or more of astigmatism, which left untreated is visually significant. Because toric intraocular lenses (IOLs) are available, the current standard of care is to offer treatment of astigmatism at the time of cataract surgery. PubMed, MEDLINE, Embase databases, and the Cochrane Library were systematically searched from inception to October 2019. Search words included astigmatism, corneal astigmatism, toric IOLs, alignment, and IOL calculation. Studies evaluated included review articles regarding the origin and history of astigmatism, the diagnosis and management of the disease, and the history of surgical management options for astigmatism. Other studies evaluated in this review included clinical trials, meta-analyses, and retrospective analysis of surgical refractive outcomes. Prediction of refractive outcomes was evaluated with a review of IOL calculators and their use in lens prediction for cataract surgery. Evaluation of these articles also showed improved uncorrected visual acuity with the use of toric IOLs in patients undergoing cataract surgery. New diagnostic technology, new toricIOLs, updated lens formulas, intraoperative guidance, and advanced imaging technology and softwarehavecontributed to improvements in the surgical correction of astigmatism.

A randomised, prospective study of 'off-the-shelf' use of toric intraocular lenses for cataract patients with pre-existing corneal astigmatism in the NHS.

To compare visual and refractive outcomes of monofocal intraocular lenses (IOLs) with limbal relaxing incisions (LRI) with 'off-the-shelf' use of toric IOLs (TIOLs), with a fixed 2-dioptre cylinder (DC) correction, for cataract patients with pre-existing corneal astigmatism in a public-sector setting. Seventy-seven patients (77 eyes, first treated eye) with visually significant cataract and pre-operative corneal astigmatism ≥2.00 DC were randomised to receive either 'off-the-shelf' TIOLs, with a fixed 2.00 DC cylinder correction (39 eyes), or monofocal IOLs (38 eyes) with LRIs. The concept of fixing the cylindrical correction was to minimise costs, allow a full TIOL bank to be available and eliminate the need for individual TIOL ordering. Outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA) and refraction. Astigmatic changes were evaluated using the Alpins vector method. Mean UDVA improved from logMAR 0.88 (SD 0.56)[~20/150] pre-operatively to 0.18 (SD 0.19)[~20/30] post-operatively in TIOL group, versus 0.82 (SD 0.55)[~20/130] to 0.27 (SD 0.15)[~20/40] in monofocal/LRI group (P = 0.02; 95% CI: -0.17, -0.01). Mean CDVA improved from logMAR 0.40 (SD 0.26)[~20/50] to 0.01 (SD 0.12)[~20/20] in TIOL group, and 0.41 (SD 0.38)[~20/40] to 0.06 (SD 0.12)[~20/25] in LRI group (P = 0.07; 95% CI: -0.11, 0.01). Average post-operative refractive cylinder in TIOL group was 1.35 DC (SD 0.84 DC) and in LRI group 1.91 DC (SD 1.07 DC) (P = 0.01; 95% CI: -1, -0.12). Mean difference vector magnitude was 1.92 DC (SD 1.08 DC) in LRI group and 1.37 DC (SD 0.84 DC) in TIOL group (P = 0.02; 95% CI: 0.11, 0.99). TIOLs with a fixed 2.00 DC correction during cataract surgery may improve UDVA, reduce post-operative cylinder and result in a more reliable astigmatic correction compared with monofocal IOLs with LRIs.

Use of Toric Intraocular Lens in Correcting Regular Astigmatism during Cataract Surgery

Background: to date Toric intraocular lenses (IOLs) have reported to be an effective method to reducepre existing refractive corneal astigmatism and so spectacle independence following cataract surgery. Aim of the Work: wasto evaluate the visual and refractive outcomes and the rotational stability of the EnvistaToric Intraocular Lens after cataract surgery in patients with pre-existing corneal astigmatism. Patients and Methods: this study included 20 Eyes of 20 patients submitted to cataract surgery with pre-existing corneal astigmatism of 1.50 D. or moreat Al-Hussein University Hospital and Nour Al-Hayah Eye Hospital between July 2017 and August 2018 that were implanted with EnvistaToric Intraocular Lens after phacoemulsification surgery Results:Using toric IOL to correct corneal astigmatism is a relatively new surgical choice in patients with a cataract and previous corneal astigmatism. After three months post operative, UCVA(Decimal), BCVA(Decimal) and Rotation(degrees) were: 0.5_1 (0.81±0.14), 0.9_1 (0.97±0.05) and 0_7 (2.75±1.65) respectively Conclusion: It could be concluded that Toric IOL implantation was a successful surgical forcorrection of astigmatism and cataractwithout affecting corneal integrity.

Use of Toric Intraocular Lens in Correcting Regular Astigmatism during Cataract Surgery

Background: to date Toric intraocular lenses (IOLs) have reported to be an effective method to reducepre existing refractive corneal astigmatism and so spectacle independence following cataract surgery. Aim of the Work: wasto evaluate the visual and refractive outcomes and the rotational stability of the EnvistaToric Intraocular Lens after cataract surgery in patients with pre-existing corneal astigmatism. Patients and Methods: this study included 20 Eyes of 20 patients submitted to cataract surgery with pre-existing corneal astigmatism of 1.50 D. or moreat Al-Hussein University Hospital and Nour Al-Hayah Eye Hospital between July 2017 and August 2018 that were implanted with EnvistaToric Intraocular Lens after phacoemulsification surgery Results:Using toric IOL to correct corneal astigmatism is a relatively new surgical choice in patients with a cataract and previous corneal astigmatism. After three months post operative, UCVA(Decimal), BCVA(Decimal) and Rotation(degrees) were: 0.5_1 (0.81±0.14), 0.9_1 (0.97±0.05) and 0_7 (2.75±1.65) respectively Conclusion: It could be concluded that Toric IOL implantation was a successful surgical forcorrection of astigmatism and cataractwithout affecting corneal integrity.

Prevalence of corneal astigmatism in cataract surgery candidates at a public hospital in Brazil.

To assess the frequency of corneal astigmatism before cataract surgery in a Brazilian sample. This clinic-based cross-sectional study was conducted at the Bonsucesso Federal Hospital, Rio de Janeiro, Brazil. Charts of patients who underwent cataract surgery over a two-year period were retrospectively reviewed, and preoperative keratometric measurements were collected and analyzed. A total of 1707 eyes of 1045 patients were enrolled. The corneal astigmatism was less than 1.0 D in 971 eyes (56.9%), 1.0-1.99 D in 496 eyes (29.1%), 2.0-2.99 D in 157 eyes (9.2%), and more than 3.0 D in 83 eyes (4.9%). The mean corneal astigmatism was 0.92 ± (SD) 0.96 D (range 0 - 10.25 D). Over 40% of the patients undergoing cataract surgery enrolled in this study had more than 1.0 D of corneal astigmatism and may benefit from the use of toric intraocular lenses. These data can be useful for planning to make this technology available for patients.

Descemet Membrane Endothelial Keratoplasty in Eyes With Previous Laser Refractive Surgery: Outcomes and Complications.

To evaluate the refractive predictability and efficacy of Descemet membrane endothelial keratoplasty (DMEK) for patients with previous laser refractive surgery. We retrospectively reviewed our cohort of endothelial keratoplasty surgical cases. We identified 21 eyes that underwent laser-assisted in situ keratomileusis (n = 17) or photorefractive keratectomy (n = 4) and were treated with DMEK for endothelial failure. Patients were analyzed preoperatively and at 6 months postoperatively for changes in visual acuity, refraction, and corneal topography. Six months after surgery, eyes significantly improved to a mean best-corrected visual acuity of 20/23 (P < 0.001). Mean astigmatism amplitude changed from 1.13 ± 0.96 preoperatively to 0.92 ± 0.51 diopters postoperatively (P = 0.28). However, shifts in the axis of corneal astigmatism ranged from 1 to 70 degrees, with 6 eyes (30%) showing an axis shift of more than 30 degrees. Spherical equivalents in nontriple procedures remained unchanged (n = 16; P = 0.69) at 6 months. DMEK and DMEK triple procedures are predictable in patients with previous refractive surgery achieving good visual results. However, refraction after the use of toric intraocular lenses may be unpredictable because of the variability in changes of the magnitude and axis of corneal astigmatism; we recommend extreme caution in the use of the toric intraocular lens in this group of patients and proper counseling for possible individual postoperative residual astigmatism.

Cataract Surgery in Patients with Keratoconus: Pearls and Pitfalls.

Background:Keratoconus (KC) is a common ectatic disorder resulting in progressive corneal thinning and irregular astigmatism. It has been observed that patients affected by KC are more likely to develop lens opacities earlier compared to non-keratoconic patients.Objective:Intraocular lens (IOL) selection and refractive outcome prediction are among a number of factors that can make cataract surgery in keratoconic patients challenging. Accurate biometry is often difficult to obtain due to unreliable K measurements and lack of dedicated biometric formulae. The use of toric IOLs has also been investigated.Conclusions:Determining the stage of KC, pre-operative patient counselling and the preferred method of refractive correction are all crucial to obtain successful postoperative outcomes and good patient satisfaction. The use of toric IOLs can achieve good results only in selected low-grade keratoconic eyes.

Correction of irregular and induced regular corneal astigmatism with toric IOL after posterior segment surgery: a case series

BackgroundToric intraocular lens (IOL) implantation can be an effective method for correcting corneal astigmatism in patients with vitreoretinal diseases and cataract. Our purpose is to report the outcome of toric IOL implantation in two cases - a patient with scleral-buckle-induced regular corneal astigmatism and a patient with keratoconus following pars plana vitrectomy. As far as we are aware, there are no reported cases of toric IOL implantation in a vitrectomized eye with keratoconus nor of toric IOL implantation in patients with scleral-buckle-induced regular corneal astigmatism.Case presentationTwo patients with myopia and high corneal astigmatism underwent cataract operation with toric IOL implantation after posterior segment surgery. Myopia and high astigmatism (>2.5 diopter) were caused by previous scleral buckling in one case and by keratoconus in the other case. Pre- and postoperative examinations during the follow-up of included uncorrected and spectacle corrected distance visual acuity (UCDVA/CDVA), automated kerato-refractometry (Topcon), Pentacam HR, IOL Master (Zeiss) axial length measurements and fundus optical coherence tomography (Zeiss). One year postoperatively, the UCDVA and CDVA were 20/25 and 20/20 in both cases, respectively. The absolute residual refractive astigmatism was 1.0 and 0.75 Diopters, respectively. The IOL rotation was within 3° in both eyes, therefore IOL repositioning was not necessary. Complications were not observed in our cases.ConclusionThese cases demonstrate that toric IOL implantation is a predictable and safe method for the correction of high corneal astigmatism in complicated cases with different origins. Irregular corneal astigmatism in keratoconus or scleral-buckle-induced regular astigmatisms can be equally well corrected with the use of toric IOL during cataract surgery. Previous scleral buckling or pars plana vitrectomy seem to have no impact on the success of the toric IOL implantation, even in keratoconus. IOL rotational stability and refractive predictability in patients with a previous vitreoretinal surgery can be as good as in uncomplicated cases.

Astigmatism Correction With Toric Intraocular Lenses in Descemet Membrane Endothelial Keratoplasty Triple Procedures.

To report the clinical efficacy of astigmatism correction with toric intraocular lenses (IOLs) in patients undergoing the Descemet membrane endothelial keratoplasty (DMEK) triple procedure and to evaluate the accuracy of the correction. Fifteen eyes of 10 patients who received cataract extraction, toric IOL placement, and DMEK surgery for Fuchs corneal dystrophy and cataracts were evaluated. The cylinder power of toric IOLs was determined by an online toric calculator with keratoscopy measurements obtained using Scheimpflug corneal imaging. Prediction errors were assessed as a difference vector between the anticipated minus postoperative residual astigmatism. At 10.1 ± 4.9 months postoperatively, 8/13 (61.5%) of eyes achieved uncorrected distance visual acuity better than 20/40. Mean best spectacle-corrected distance visual acuity (logMAR) improved from 0.21 ± 0.15 preoperatively to 0.08 ± 0.12 postoperatively (P < 0.01). The magnitude of refractive astigmatism was also significantly decreased from 2.23 ± 1.10 D (range 0.75-4.25 D) preoperatively to 0.87 ± 0.75 D (range 0.00-3.00 D) postoperatively (P < 0.01). In 1 eye with rotational misalignment by 43 degrees, we found no improvement of astigmatism. The prediction error of astigmatism at the corneal plane was 0.77 ± 0.54 D (range 0.10-1.77 D). Four eyes with preoperative "with-the-rule" corneal astigmatism had postoperative "against-the-rule" refractive astigmatism. For patients with Fuchs corneal dystrophy and cataracts, use of toric IOLs might be a valuable option in triple DMEK surgery. Additionally, care should be taken to prevent excessive IOL rotation.

Do evidence-based guidelines change clinical practice patterns?

In 2013, the Danish Health and Medicines Authorities published a National Clinical Guideline on the treatment of age-related cataracts. The guideline provided evidence-based recommendations on the indication for cataract surgery, cataract surgery in patients with age-related macular degeneration, on the use of toric intraocular lenses (IOLs) to correct preoperative corneal astigmatism, the use of intracameral and topical antibiotics to prevent endophthalmitis, choice of anti-inflammatory medication to control postoperative inflammation and prevent cystoid macular oedema, the use of immediate sequential bilateral cataract surgery and on the postoperative check-up of patients. A questionnaire was sent to all members of the Danish Ophthalmological Society before and after publication of the guideline. The responses showed that the guideline had changed practice patterns so that surgeons were more likely to prescribe non-steroidal anti-inflammatory eye drops and to not prescribe topical antibiotic eye drops after the guideline was published. Other parameters, most notably the use of toric IOLs and use of postoperative examinations were more guided by reimbursement standards than by evidence-based medicine. Thus, evidence-based guidelines do change practice patterns unless they are counteracted by the reimbursement system.

Prevalence of corneal astigmatism before cataract surgery in Indian population.

The purpose of the study was to assess the prevalence of corneal astigmatism before cataract surgery in Indian population. The setting of this study was at the Sant Sarwan Dass Charitable Eye Hospital, Jalandhar, India. This is a clinic-based retrospective study. Charts of patients who underwent cataract surgery over a two-year period were retrospectively reviewed, and preoperative keratometric measurements were collected and analyzed. The mean age of 2316 patients (2502 eyes) was 59.54±10.96years. The corneal astigmatism was less than 1.0 Dioptre (D) in 796 eyes (59.37%), 1.0-1.99D in 716 eyes (28.62%), 2.0-2.99D in 187 eyes (7.47%) and more than 3.0 D in 114 eyes (4.56%). The mean corneal astigmatism was 1.04±1.04 D and showed a gradual increase with age after the fourth decade. The astigmatism was with-the-rule in 709 (28.34%), against-the-rule in 1298 (51.88%), and oblique in 598 (23.9%) eyes. There was a shift in astigmatism from with-the-rule to against-the-rule with increase in age. Over 40% of the Indian patients undergoing cataract surgery have more than 1.0 D of corneal astigmatism and may benefit from the use of toric intraocular lenses. These data can be useful in planning to make this technology available for the patients.

Corneal Astigmatism Stability in Descemet Membrane Endothelial Keratoplasty for Fuchs Corneal Dystrophy.

To calculate the magnitude and angle of the shift in corneal astigmatism associated with Descemet membrane endothelial keratoplasty (DMEK) surgery to determine the feasibility of concurrent astigmatism correction at the time of DMEK triple procedures. Retrospective study. Forty-seven eyes that previously underwent the DMEK procedure for Fuchs endothelial corneal dystrophy and that had more than 1.0 diopter (D) of front corneal astigmatism preoperatively were identified. All DMEK surgeries used a clear corneal temporal incision of 3.2 mm. Surgically induced astigmatism (SIA) was evaluated 6 months postsurgery with vector analysis using Scheimpflug image reading. We did not find a difference between pre- and postoperative magnitude of front astigmatism (P = 0.88; paired t test). The magnitude of the SIA front surface was 0.77 ± 0.63 D (range, 0.10-3.14 D). The centroid vector of the SIA front surface was 0.14 at 89.3°. A hyperopic corneal power shift was noted in both the front surface by 0.26 ± 0.74 D (range, 0.45-3.05 D) (P = 0.018; paired t test) and back surface by 0.56 ± 0.55 D (range, 0.25-2.40 D) (P < 0.01; paired t test). DMEK surgery induces minimal amounts of corneal astigmatism that is a with-the-rule shift associated with a temporal clear corneal incision. The stability of these data from preop to postop supports the plausibility of incorporating astigmatism correction with the cautious use of toric intraocular lenses for patients with Fuchs corneal dystrophy and cataract.

Evaluation of the Results of Using Toric IOL in the Cataract Surgery of Keratoconus Patients.

To evaluate the results of using AcrySof toric intraocular lenses (IOLs) in the cataract surgery of patients with keratoconus (KCN). In this study, 23 eyes of 17 patients with KCN who underwent cataract surgery using the toric IOL were evaluated. The amount and axis of the corneal astigmatism were measured by manual keratometry, corneal topography, refractive map of the Pentacam, and equivalent K reading of the Pentacam in all patients. The mean uncorrected visual acuity increased significantly 3 months after the surgery (P<0.01). The mean best-corrected visual acuity was 0.28±0.10 logMAR, 0.51±0.52 logMAR, and 0.83±0.55 logMAR before the surgery and 0.16±0.09 logMAR, 0.18±0.12 logMAR, and 0.35±0.13 logMAR after the surgery in the mild, moderate, and severe KCN groups, respectively (P<0.01). The mean IOL rotation was 2.50±1.18 degrees, 2.50±1.51 degrees, and 2.67±1.15 degrees in the mild, moderate, and severe KCN groups. The lowest mean absolute error was seen in the mild and moderate KCN groups with corneal topography-derived keratometry using the SRK/T formula and in the severe KCN group with corneal topography-derived keratometry and manual keratometry using the SRK/T and SRK II formulas. The use of toric IOLs resulted in desirable vision and refraction in the cataract surgery of patients with nonprogressive KCN. As for determining the IOL power, it seems that keratometry derived from the 3 mm central zone in the axial map of corneal topography using the SRK/T formula has the lowest error.

The use of toric intraocular lens to correct astigmatism at the time of cataract surgery.

Background:To evaluate the visual and refractive outcomes of cataract surgery with toric intraocular lens (IOL) implantation at a teaching hospital of the United Kingdom.Design:Prospective interventional case series.Materials and Methods:This study compared the outcome of 3 groups of patients: Group 1 included 25 eyes with cataract and more than 2.5 diopters (D) of corneal astigmatism receiving a toric monofocal IOL; Group 2 had 18 patients with cataract and more than 2.5 D of astigmatism but receiving a non-toric monofocal IOL; while Group 3 had 25 patients with cataract and less than 1.5 D of astigmatism and receiving a non-toric monofocal IOL. Data collected included uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction and corneal keratometry. Postoperative examinations were scheduled at 1 and 6 weeks.Results:Postoperatively the mean UDVA was LogMAR 0.27 ± 0.20 (equivalent snellen acuity of 20/37) in Group 1, 0.54 ± 0.22 (20/69) in Group 2 and 0.16 ± 0.20 (20/29) in Group 3. The mean CDVA was LogMAR 0.08 ± 0.13 (20/24) in Group 1, 0.23 ± 0.16 (20/34) in Group 2 and 0.04 ± 0.13 in Group 3 (20/22). The mean preoperative keratometric cylinder was 3.78 ± 1.0 D in Group 1, 3.41 ± 1.47 D in Group 2 and 0.97 ± 0.43D in Group 3; the mean postoperative subjective cylinder was 1.2 ± 0.68 D in Group 1, 3.23 ± 1.41 D in Group 2 and 0.95 ± 0.58 D in Group 3. The difference was statistically significant for the postoperative refractive cylinder values when comparing Group 1 to Group 2 (P = <0.0001) but the difference was insignificant between Group 1 and Group 3 (P = 0.23).Conclusion:Toric IOL implantation is an effective option to manage corneal astigmatism at the time of cataract surgery and to optimise visual outcomes for astigmatic patients when comparing to outcomes for their non-astigmatic counterparts.

PSS19 - Analysis Of Cost-Effectiveness Of Use Of Toric Intraocular Lenses Compared With Traditional Monofocal Lenses In Patients With Cataracts And Pre-Existing Corneal Astigmatism

evaluate the cost-effectiveness of the use of toric intraocular lenses (IOLs) in surgery of patients with cataract and preexisting corneal astigmatism (> 0.75 D), versus the use of traditional monofocal intraocular lenses (IOLs) from the perspective of third party payer, as a way to define which technology could considered in the health care reimbursement. in a decision tree type model was simulated the cataracts surgery intervention in a time horizon of five years. The outcome measure was the cumulative visual acuity of 20/32, which was expressed in normal vision time without additional support. The drug costs were taken from SISMED (2013), the costs from multi-core procedures of the health ministry (SISPRO), the cost of glasses and contact lenses from commercial channel, and the cost of IOLs were taken as the selling price of Alcon Laboratories. Finally a Montecarlo type sensitivity analysis was performed. as primary outcome, time normal distance vision without additional support was higher with toric IOLs, which it were more effective at 3,64 years versus 2,97 years achieved with traditional monofocal IOLs. Intervention with toric IOLs showed in the time horizon of five years be more expensive with (USD) $1.093,55 versus costs of traditional monofocal IOLs (USD) $732,71. In this regard cataract surgery is more effective and more costly with toric IOLs than with traditional monofocal IOLs with an incremental cost-effectiveness ratio of (USD) $534,83 per each year of normal vision without additional support. It was observed that the ICER improves if there is a greater visual impairment due to astigmatism before surgery, as well, to diopters <1.50, >1.50 <2.00 and >2.00 the ICER was (USD) $ 712.40, (USD) $ 416.75 and (USD) $ 382.16 respectively. toric IOLs proved to be cost-effective for the treatment of patients with cataract and preexisting astigmatism.