Limbal Relaxing Incisions Research Articles

Limbal relaxing incisions at the time of apodized diffractive multifocal intraocular lens implantation to reduce astigmatism with or without subsequent laser in situ keratomileusis

To evaluate the visual and refractive outcomes of limbal relaxing incisions (LRIs) to reduce astigmatism at the time of apodized diffractive multifocal intraocular lens (IOL) implantation. University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA. This retrospective review comprised consecutive patients who had LRIs at the time of lens extraction and AcrySof ReSTOR IOL implantation. A subgroup of patients had subsequent laser in situ keratomileusis (LASIK) for residual refractive error correction. The study evaluated 73 eyes (59 patients); 21 eyes (28.7%) of 59 patients had further LASIK (LRI+LASIK). The mean follow-up was 13.2 months +/- 6.4 (SD). The mean keratometric astigmatism decreased from 1.49 +/- 0.71 diopters (D) preoperatively to 0.56 +/- 0.57 D at the last follow-up (P<.001). Although the LRI+LASIK group had significantly greater corneal astigmatism than the LRI-only group preoperatively (P = .005) and 1 month (P = .030) and 6-months (P = .014) postoperatively, there was no statistically significant difference between the 2 groups at the last follow-up (P = .528). At the last follow-up, the uncorrected distance visual acuity was 20/25 or better and the uncorrected near visual acuity was J1 or better in 32 (76%) of 42 eyes in the LRI-only group and in 17 (81%) of 21 eyes in the LRI+LASIK group. Limbal relaxing incisions at the time of apodized diffractive multifocal IOL implantation, with or without subsequent LASIK, were effective and safe in reducing astigmatism.

Refractive Surgery Trends and Practice Style Changes in Germany Over a 3-year Period

To study the current practice styles and preferences of refractive surgeons in Germany. In February 2008, a seven-item questionnaire regarding the practice of refractive surgery was mailed to 282 members of the German Society of Intra-ocular Lens Implantation, Interventional, and Refractive Surgery (DGII) and the Commission of Refractive Surgery (KRC). Most questions were identical to our 2005 German refractive surgery survey. All data were analyzed in a masked fashion. The response rate was 42.2%. The majority (68%) of respondents reported that they perform refractive surgery in laser centers (exclusively or partially) followed by general hospitals (19.4%) and universities (12.6%). Although LASIK was the predominant type of refractive surgery performed (80.6%), other refractive procedures included refractive lens exchange (60.2%), photorefractive keratectomy (47.6%), phakic intraocular lens implants (45.6%), laser-assisted subepithelial keratectomy (36.9%), epithelial laser in situ keratomileusis (15.5%), intracorneal rings (5.8%), and limbal relaxing incisions (2.9%). The volume of refractive surgery procedures and the preferred type of excimer laser systems, microkeratomes, and diagnostic devices varied at different institutions. Most respondents performed either wavefront-guided custom ablation or wavefront-optimized ablation (63.1%) compared with conventional excimer laser correction (36.9%). Refractive surgery practice styles and preferences in Germany are comparable to trends in other European countries. Although LASIK is the most commonly performed refractive procedure, the numbers of various surface ablation techniques and refractive intraocular lens procedures are increasing.

Early Bubble Modification of the Big Bubble Technique for Deep Anterior Lamellar Keratoplasty

We modified the deep anterior lamellar keratoplasty big bubble technique to improve safety and ease of performance. We describe a modification of the big bubble technique that involves injecting the air bubble through a peripheral corneal incision 1 mm from the limbus. The incision is made with a limbal relaxing incision knife. This is done before trephination of the recipient cornea, hence the name "early bubble." The goal of this technique is to reduce the risk of intraoperative corneal perforation and to obtain a large air bubble between Descemet membrane and the corneal stroma. We report outcomes of this technique in 21 eyes. At 6 months, 16 eyes showed a best-corrected visual acuity of 20/50; the remaining eyes had a best-corrected visual acuity of 20/80 or better. The postoperative corneal astigmatism was 3.6+/-0.9 diopters at 3 months and 3.15+/-0.67 diopters at 6 months. The rate of conversion to penetrating keratoplasty was 14%. We found that the "early bubble" technique improved the ease of performance, safety, and predictability of deep anterior lamellar keratoplasty.

Limbal relaxing incision during cataract extraction versus photoastigmatic keratectomy after cataract extraction in controlling pre-existing corneal astigmatism

The techniques of limbal relaxing incision (LRI) and photoastigmatic keratectomy (PAK) are both effective methods for correcting pre-existing astigmatism with cataract extraction, but no previous study has directly compared them. To compare the effects of limbal relaxing incision (LRI) and photoastigmatic keratectomy (PAK) on preoperative astigmatism and higher-order aberrations (HOAs) in eyes undergoing cataract surgery. Kitasato University Hospital, Japan. A retrospective study of eyes which had undergone phacoemulsification and intraocular lens implantation through an astigmatically neutral incision either accompanied by LRI (LRI group, 20 eyes) or followed after 3 months by PAK (PAK group, 27 eyes), to control pre-existing corneal astigmatism. Among eyes that underwent LRI, manifest astigmatism (corrected to the corneal plane) averaged -1.72 +/- 0.95 D preoperatively and -0.98 +/- 0.58 D postoperatively. Corneal astigmatism averaged 2.03 +/- 0.49 D preoperatively and 1.34 +/- 0.60 D postoperatively. Among eyes that underwent PAK, manifest astigmatism averaged -2.02 +/- 0.64 D preoperatively and -0.70 +/- 0.58 D postoperatively. Corneal astigmatism averaged 2.30 +/- 0.81 D preoperatively and 1.05 +/- 0.36 D postoperatively. With regard to HOAs, in the LRI group, corneal HOAs averaged 0.172 +/- 0.051 microm (total aberrations for 4 mm pupil diameter) and 0.681 +/- 0.433 microm (total, 6 mm) preoperatively, but 0.172 +/- 0.053 microm (total, 4 mm) and 0.651 +/- 0.187 microm (total, 6 mm) postoperatively. In the PAK group, the corneal HOAs averaged 0.179 +/- 0.073 microm (total, 4 mm) and 0.679 +/- 0.314 microm (total, 6 mm) preoperatively, but 0.206 +/- 0.095 microm (total, 4 mm) and 0.816 +/- 0.380 microm (6 mm, total) postoperatively. The only statistically significant differences in the postoperative HOAs between LRI and PAK groups were in the S4 and S6 (spherical and spherical-like aberrations being bigger in the PAK group ).There were no vision-threatening complications in either group. PAK is more effective than LRI in the control of pre-existing manifest astigmatism. LRI causes less accentuation of the spherical HOAs than PAK.

The Short Term Effects of a Single Limbal Relaxing Incision Combined with Clear Corneal Incision

PurposeTo compare the effects of performing a single limbal relaxing incision (LRI) combined with a clear corneal incision on a corneal astigmatism with that of paired LRIs in cataract surgery.MethodsMedical records for 25 eyes in 20 patients who had undergone LRIs during cataract operations for with-the-rule astigmatism of 1.5 diopters (D) or more in topography were retrospectively reviewed. Single or paired LRIs were assigned randomly and were performed on the steepest axis; the degrees of arc were determined using the modified Gills nomogram. A clear corneal wound was made on the steepest vertical axis. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest refraction, and corneal astigmatism on topography were evaluated preoperatively and one month postoperatively. Naeser's polar value analysis was used to assess the efficacy of the LRIs.ResultsThe mean depth of the LRIs and degrees of arc were 620±31 µm (87.1% of corneal thickness) and 56.84±19.68°, respectively. The mean postoperative UCVA and BCVA (log MAR) were significantly improved (0.51±0.37 and 0.09±0.12, respectively) (p<0.05). Average refractive and corneal astigmatisms were significantly reduced by 49.4 percent and 32.4 percent, respectively (p<0.05). The single LRI combined with clear corneal incision showed reduced efficacy in refractive astigmatism by 47 percent, which is similar to that of paired LRIs where a 48 percent reduction in efficacy was seen.ConclusionsThe short-term effects of a single LRI combined with clear corneal incision on a corneal astigmatism appears to be as effective as performing paired LRIs when combined with cataract incision.

Implantable Collamer Lens Implantation and Limbal Relaxing Incisions for the Correction of Hyperopic Astigmatism After Laser In Situ Keratomileusis

To report on a patient in whom hyperopic Implantable Collamer Lenses (ICL, STAAR Surgical, Nidau, Switzerland) and limbal relaxing incisions have been beneficial for the correction of hyperopic astigmatism after laser in situ keratomileusis (LASIK). The 48-year-old man had undergone LASIK to correct high myopia 5 years earlier. Preoperatively, the manifest refraction was +2.25, -1.00 x 160, with an uncorrected visual acuity of 0.15 and a best spectacle-corrected visual acuity of 1.5. Postoperatively, the manifest refraction was +0.50, -0.5 x 165, with an uncorrected visual acuity of 1.0 and a best spectacle-corrected visual acuity of 1.2. No serious complications were observed during the 10-month observation period. Hyperopic Implantable Collamer Lenses implantation combined with limbal relaxing incisions may be an alternative for the treatment of hyperopic astigmatism after overcorrected myopic LASIK.

Prospective Randomized Trial of Limbal Relaxing Incisions Combined with Microincision Cataract Surgery

To evaluate clinical outcomes of limbal relaxing incision (LRI) combined with bimanual phacoemulsification and insertion of an intraocular lens (IOL) developed for bimanual microincision cataract surgery (MICS). In a prospective, single-center study, eyes with > or = 0.75 diopters (D) of keratometric astigmatism were randomly assigned to two surgical techniques: 1) bimanual MICS (non-LRI group) or 2) LRI combined with bimanual MICS (LRI group). Postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), postoperative refractive error, corneal topography, and vector analysis of keratometric change between pre- and postoperative eyes were compared. In all cases of astigmatism in the LRI group, incisions for phacoemulsification and IOL insertion did not overlap or affect the LRIs. Uncorrected distance visual acuity was significantly higher in the LRI group (mean: 0.94) than in the non-LRI group (mean: 0.71, P = .009), although no difference was seen in CDVA in either group. Postoperative cylindrical error was significantly lower in the LRI group than in the non-LRI group (0.56 D and 1.51 D, respectively, P = .0004). Cravy analysis showed that the vector change in cylinder was 1.44 D in the LRI group and 0.18 D in the non-LRI group (P = .0007). Limbal relaxing incision with bimanual MICS is an easy-to-follow combined surgery to correct preexisting astigmatism with predictable accuracy.

Effect of Limbal Relaxing Incisions During Phacoemulsification Surgery Based on Nomogram Review and Numerical Simulation

To determine the effect of the parameters related to limbal incisions (length, depth, optical zone, and so on) by revision of different nomograms and analyzing the outcomes of numerical simulation of incisions with a biomechanical model of the cornea. The Cristóbal nomogram was developed based on our experience on the performance of relaxing incisions to correct astigmatism. A numerical model of the eye was used to analyze the effect induced by variation of each parameter compiled in nomograms. The biomechanical properties remained invariable for all cases. Different incisions were simulated to study the influence of each parameter, being one varied while the others remain constant, under equal biomechanical conditions, ignoring the human factor. Quantitatively, simulation of incisions of 45, 60, and 90 degrees; optical zone of 10 mm; and depth of 90% of the thickness induced astigmatic changes of 1.2, 1.4, and 1.9 diopters (D). Paired incisions at 7.5-mm optical zone and 90-degree length induced astigmatic changes of 0.7, 2.6, and 4.4 D for 40%, 75%, and 90% depth, respectively. Paired incisions of 90-degree length and 90% depth for 10- and 7.5-mm optical zones induced 1.9 and 4.4 D, respectively. Qualitatively, the results confirm the guidelines compiled in nomograms. The revision of some nomograms for limbal incisions to correct astigmatism, compared with the outcomes of numerical simulation, leads to common guidelines. Numerical simulation supplies theoretical outcomes that the clinician can take into account to decide the values of the parameters for the surgery, in addition to their clinical experience.

Chirurgische Astigmatismuskorrektur bei der Kataraktoperation

To enhance patients' postoperative optical quality after cataract surgery, among others, different procedures to correct corneal astigmatism are used. An overview is presented on procedures to correct astigmatism during cataract surgery, based on a selective literature review and the authors" own experience. Described are incisional techniques to change the corneal curvature as well as the implantation of toric posterior chamber intraocular lenses (IOL) after phacoemulsification. Further on patient selection and indications of the different methods are illustrated. In particular, limbal relaxing incisions provide satisfying results in astigmatism correction of up to 2 diopters, if published and surgeons individual nomograms are used. Larger astigmatism of up to about 30 diopters may be corrected with toric IOL. Compared to incisional techniques, those toric implants provide better predictability and precision and suffer less from regression. Usually the focus of cataract surgery is the correction of aphakia. Today's techniques and implants, however, offer surgeons the chance to individualize patients postoperative astigmatism and thus increase overall patient satisfaction.

Presbyopia Treatment by Monocular Peripheral PresbyLASIK

To investigate monocular peripheral presbyLASIK on the non-dominant eye with distance-directed monofocal refractive surgery on the dominant eye in treating presbyopia. One hundred three patients underwent treatment with a VISX S4 system and follow-up from 1.1 to 3.9 years (mean 27.4 months). Average patient age was 53.3 years. Preoperative refraction ranged from -9.75 to +2.75 diopters (D). Non-dominant eyes underwent peripheral presbyLASlK--an aspheric, pupil-size dependent LASIK to induce central corneal relative flattening and peripheral corneal relative steepening. Dominant eyes underwent monofocal refraction-based LASIK (75.8%), wavefront-guided LASIK, limbal relaxing incisions, or no treatment to optimize distance vision. At final follow-up, 91.3% (94/103) of all patients, 89% (25/28) of hyperopes, and 92% (69/75) of myopes reported complete spectacle independence and 7.8% (8/103) used spectacles for less than 1 hour per week. Distance unaided visual acuity was at least 20/20 in 67.9% (19/28) of hyperopes and 70.7% (53/75) of myopes, at least 20/20 at 80 cm in 85.7% (24/28) of hyperopes and 84% (63/75) of myopes, and at least 20/20 at 40 cm in 71.4% (20/28) of hyperopes and 65.3% (49/75) of myopes, PresbyLASIK increased overall higher order aberrations similarly to refraction-based LASIK for myopes but to a greater extent in hyperopic cases. PresbyLASIK WaveScan spherical equivalent refraction was stable in myopes but migrated an average +0.31 D in hyperopes over the follow-up period. Monocular peripheral presbyLASIK is a valuable option for presbyopic patients considering refractive surgery.

Kératotomies arciformes périphériques et correction de l’astigmatisme dans la chirurgie de la cataracte

To evaluate the effectiveness of limbal relaxing incisions for correcting significant preoperative astigmatism during cataract surgery.In 32 patients (50 eyes) with preoperative keratometric astigmatism between 1.25 and 2.5 D, cataract surgery was combined with limbal relaxing incisions according to a modified Gills nomogram.The mean preoperative keratometric astigmatism was 1.6 (+/- 0.39) D. The mean preoperative manifest refraction was 1.26 ((+/- 0.39) D. The mean 1-month, 6-month and 3-year or more postoperative keratometric astigmatisms were 0.77 ((+/- 0.29), 0.84 ((+/- 0.5) and 0.86 ((+/- 0.32) D, respectively. The mean postoperative manifest refractions were 0.48 ((+/- 0.32), 0.55 ((+/- 0.29) and 0.54 ((+/- 0.29) D, respectively. Postoperative refractive astigmatisms were 0 or 0.25 D in 22% of the cases, 0.5 or 0.75 D in 64% and greater than 0.75 D in 14%. Conclusion.- Limbal relaxing incisions are an effective and simple approach to the correction of significant preoperative astigmatism during cataract surgery.

Limbal relaxing incisions and Graves ophthalmopathy with lower eyelid retraction

Limbal relaxing incisions (LRI) were performed in a 35-year-old man with Graves ophthalmopathy and lower eyelid retraction. He underwent intraocular lens exchange in 1 eye and cataract surgery in the other. Despite the return of normal thyroid function, aggressive lubrication, and antiinflammatory medication, the LRIs failed to heal, leaving gaps in the limbal cornea. Limbal relaxing incisions should be avoided in Graves ophthalmopathy with lower eyelid retraction and/or exposure keratopathy.

Reply: Is Peripheral PresbyLASIK a Centerdistance Technique?

&lt;H4&gt;Modified Astigmatism Correction Nomogram&lt;/H4&gt; &lt;p&gt;&lt;B&gt;To the Editor:&lt;/B&gt;&lt;br&gt;I would like to congratulate Carvalho et al on their article reviewing their use of limbal relaxing incisions (LRI) to reduce astigmatism at the time of cataract surgery, which appeared in the May 2007 issue of the &lt;cite&gt;Journal of Refractive Surgery&lt;/cite&gt;. This report further documents the safety and efficacy of this surgical technique, lending support to similar studies within the literature. [more...]&lt;/p&gt;

Incisões relaxantes limbares ou incisões no meridiano mais curvo associadas a facoemulsificação com implante de lente intra-ocular multifocal: relato de três casos

The use of multifocal intraocular lenses (IOLs) is a great advance in the treatment of patients with cataract allowing near and distance uncorrected visual acuity recovery. However patients with some degrees of corneal astigmatism have some limitations. We present 3 cases that were indicated for phacoemulsitfication and multifocal intraocular lens implant (AcrySof Restor, Alcon Labs) after limbal relaxing incision (LRI) in the dominant eye and axis topographic incision in the fellow eye. There was no similar case report in the literature. It is believed that this association can extend the indications for multifocal intraocular lens implants in patients with significant corneal astigmatism and this possibility should be confirmed by future studies.

Patient-centered care and refractive cataract surgery

Cataract surgery has evolved significantly during the last few years. The introduction of aspheric, presbyopic correcting and toric intraocular lenses have shifted the emphasis of cataract surgery from just treating patients' functional symptoms to optimizing the refractive outcome of the procedure. Studies emphasizing patient satisfaction and refractive visual outcomes have shifted the focus of cataract surgery to a more patient-centered approach. Refractive surgical technologies such as limbal relaxing incisions, laser-assisted in-situ keratomileusis, photorefractive keratectomy and conductive keratoplasty can be used in conjunction with traditional cataract surgical techniques. The wide array of intraocular lens choices has broadened the scope of refractive cataract surgery providing surgeons and patients with more options in determining refractive outcomes. Cataract surgery has expanded into the realm of refractive surgery and there is a new emphasis on patient-centered care and an optimization of the refractive outcome of the procedure. This trend will continue as newer presbyopic correcting intraocular lenses become available.

Incisiones limbares relajantes y cirugía de la catarata: nuestra experiencia

To evaluate the reduction of pre-existing corneal astigmatism at the time of cataract surgery with limbal relaxing incisions (LRIs). A prospective study of two groups of patients (treatment and control) with pre-existing astigmatism>or=1D was performed. The 30 patients in the control group had a temporal clear corneal phacoemulsification and the 32 patients of treatment group had combined temporal clear corneal phacoemulsification and LRIs. Holladay analysis was used to assess the efficacy of treatment. An astigmatism distribution and prevalence study in our population is also presented. Three months after surgery, the mean astigmatism change was -0.55D (-0.75 to -0.35) in the treatment group and 0.04D (-0.3 to 0.3) in the control group (p<.0001). LRI is a simple, safe and effective method not only for reducing pre-existing astigmatism during cataract surgery but in providing good unaided visual acuity.

Update on customized wavefront-guided versus wavefront-optimized excimer laser ablation: next steps in the quest for perfect vision

The pace of advancement in refractive surgical techniques and evolution of technology in recent years has been remarkably brisk. The increase in technologies and treatment options, however, has left many ophthalmologists uncertain as to which are the optimal choices for their patients and practices. Some of this dilemma undoubtedly arises from the expanding ‘alphabet soup’ of refractive technical terms: radial keratotomy (RK), astigmatic keratotomy (AK), limbal-relaxing incisions (LRI), photorefractive and astigmatic keratectomy (PRK) and (PARK), laser in situ keratomileusis (LASIK), laser subepithelial keratomileusis (LASEK), epithelial laser in situ keratomileusis (Epi-LASIK), IntraLase LASIK (Intra-LASIK), intracorneal ring segments (ICRS), laser thermokeratoplasty (LTK), conductive keratoplasty (CK), phakic intraocular lenses (PIOL), clear lens extractions (CLE), refractive lens exchange (RLE) and scleral expansion (SE), to name just a few. Within the parameters of a single technology, such as laser vision correction (LVC), there are numerous approaches to optimizing visual outcomes. For example, in the last 5 years, the development of wavefront technology has revolutionized the way refractive surgeons view and treat refractive error. The discussion continues, however, as to when or how to best use this technology. To date, there are two wavefront-based approaches to LVC: wavefront guided and wavefront optimized. The purpose of this article is to discuss the use of wavefront analysis and to explore wavefront-guided and wavefront-optimized approaches in LVC.

Limbal Relaxing Incisions to Correct Corneal Astigmatism During Phacoemulsification

To evaluate the safety and efficacy of limbal relaxing incisions for the correction of corneal astigmatism during phacoemulsification. Fifty eyes of 37 patients (mean age 66.5 years, range: 45 to 80 years) with cataract and coexisting topographic astigmatism were included in the study. Eyes were randomly divided into two groups: eyes that underwent cataract surgery with limbal relaxing incisions (cataract LRI group) and eyes that underwent cataract surgery only (control group). All limbal relaxing incisions were performed during phacoemulsification. Best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), and corneal topography were recorded preoperatively and 1, 3, and 6 months postoperatively. A statistically significant improvement in BSCVA was seen in the cataract LRI eyes from 0.9 +/- 0.7 preoperatively to 0.1 +/- 0.1 at 1, 3, and 6 months postoperatively (P < .01). A statistically significant improvement in BSCVA was seen in control eyes from 0.8 +/- 0.6 before surgery to 0.2 +/- 0.2 at 1, 3, and 6 months after surgery (P < .01). No difference in postoperative BSCVA was noted between the groups. A statistically significant reduction in the mean topographic astigmatism was seen in the cataract LRI eyes from 1.93 +/- 0.58 diopters (D) preoperatively to 1.02 +/- 0.60 D 6 months postoperatively (P < .05). The control eyes did not show a statistically significant change in topographic astigmatism. Limbal relaxing incisions performed during phacoemulsification surgery appear to be a safe, effective, and stable procedure to reduce pre-existing corneal astigmatism.

Status of toric intraocular lenses

To provide an update on the status of toric intraocular lenses. These lenses can be used as an alternative or adjunct to corneal astigmatic incisions for correcting preexisting astigmatism in patients with cataracts. They are a particularly attractive option in those cases where limbal-relaxing incisions are not powerful or predictable enough. Other toric lenses may correct astigmatism in addition to spherical refractive errors in phakic patients. Toric lenses have continued to gain popularity with the US Food and Drugs Administration (FDA) approval of the Acrysof Toric intraocular lenses. This lens is designed to be implanted in patients undergoing cataract removal and who have significant preexisting corneal astigmatism. In the FDA clinical trial, study patients received one of the three cylindrical powers, and control patients received a standard monofocal intraocular lenses. The study found that the Acrysof Toric intraocular lenses provided excellent visual outcomes and exhibited excellent rotational stability. With the Acrysof Toric intraocular lenses, the average lens rotation was less than 4 degrees from the lens' initial placement at 6 months after surgery. Toric intraocular lenses provide excellent vision for astigmatic cataract patients, and new designs are significantly improving visual acuity by minimizing the risk of rotation.

Astigmatism control.

Refractive cataract surgery has become a reality for the modern phacosurgeon, and control of astigmatism plays a vital role in this quest for optical refractive outcomes. Fortunately, a number of effective options exist to minimize postoperative cylinder. These include placing the cataract incision on the steep corneal meridians; use of adjunctive corneal or limbal relaxing incisions; or even using advanced technology, such as the excimer laser. Careful attention must be directed to the measurement of pre-existing astigmatism, and a detailed surgical strategy must then be formulated. Finally, one must be able to avail themselves of enhancement techniques to address residual astigmatism.