Temporal Clear Corneal Incision Research Articles

Prediction of postoperative refractive astigmatism before toric intraocular lens implantation

BackgroundTo determine the preoperative factors influencing refractive astigmatism after cataract surgery for astigmatism correction by toric intraocular lens (IOL) implantation and to evaluate the prediction model using these factors.MethodsProspective, observational case series. The right eyes of forty consecutive patients with preoperative corneal astigmatism of the total cornea of 1.5 diopters (D) or more in magnitude and scheduled for implantation of a non-toric IOL during cataract surgery with a 2.4-mm temporal clear corneal incision were examined prospectively. The vertical/horizontal astigmatism component (J0) and oblique astigmatism component (J45) of refractive and corneal astigmatism were converted using power vector analysis. Multivariate regression analysis was performed with refractive astigmatism at three months postoperatively as the dependent variable, and preoperative parameters including age, sex, refractive astigmatism, corneal astigmatism, sphere, spherical equivalent, intraocular pressure, corneal thickness, anterior chamber depth, lens thickness, lens positions (tilt and decentration), axial length, and corneal higher order aberrations as independent variables. The root mean square (RMS) errors were calculated to express the regression model fit.ResultsThe regression model for the J0 component was Postoperativekern0.34em refractivekern0.2em J0=1.05times Conealkern0.2em J0-0.14 (R2 = 0.96, P < 0.001). The model for the J45 component was Postoperativekern0.34em refractivekern0.2em J45=0.68times Conealkern0.2em J45+0.19times Preoperativekern0.34em refractivekern0.2em J45-0.06 (R2 = 0.72, P < 0.001). The mean RMS errors for preoperative corneal astigmatism alone and the multivariate model were 0.58 D and 0.46 D, respectively. There was a statistically significant difference between them (P = 0.02).ConclusionsRefractive astigmatism after implantation of a toric IOL can be predicted by the regression model more accurately than by corneal astigmatism alone. However, the prediction of oblique astigmatism remains a challenge.

Wound integrity of modified anterior stromal hydration Vs. conventional hydration after clear corneal incision phacoemulsification.

Purpose:To compare the self-sealing ability of temporal clear corneal incisions for phacoemulsification using conventional stromal hydration (CH) with two modified methods: the anterior stromal pocket hydration (ASPH) and the modified stromal pocket hydration (MASH).Methods:Patients undergoing routine phacoemulsification surgeries were randomized to receive the CH, ASPH, and MASH (n = 30 eyes in each group). In the ASPH, an anterior stromal pocket was created superficial and parallel while in the MASH; it was superficial and perpendicular to the plane of the main incision. The primary outcome measure was wound leakage assessed after applying firm downward pressure on the posterior lip of the main corneal incision, simulating eye rubbing.Results:On application of pressure to the posterior lip, leakage was seen from 19 eyes (63%) in the CH group, while this was seen in only two eyes (7%) each in the ASPH and MASH groups (P < 0.001). The likelihood of wound leak after applying pressure to the posterior lip reduced by 86% in the ASPH and MASH groups compared to CH (Odds ratio = 0.14, 95% CI = 0.05 – 0.35, P < 0.001). The mean surgically induced astigmatism was 0.18 ± 0.14D and there were no differences in SIA across the three groups (P = 0.42). More eyes in the ASPH required conversion to CH (n = 4, 13%) due to difficulty in localizing the pocket compared to MASH (n = 0, P = 0.03)Conclusion:Both, the ASPH and MASH techniques reduce the risk of wound leakage and do not induce astigmatism. The MASH technique makes it easier to consistently localize the pocket.

Cataract Surgery in Dry Eye Disease: Visual Outcomes and Complications.

Purpose: To describe the visual outcomes and complications following cataract surgery in dry eye disease (DED).Methods: This retrospective study included 668 eyes of 399 patients with DED, who underwent cataract surgery between 2011 and 2019 at our multi-tier ophthalmology hospital network. Based on etiology, they were divided into three groups: cicatrizing conjunctivitis (CC), meibomian gland dysfunction (MGD), and Sjogren's syndrome (SS). The data on demographics, visual impairment, surgical technique, visual outcomes, and complications were collected using an electronic medical record system. Median LogMAR best corrected visual acuity (BCVA) with interquartile range (IQR) was compared using Wilcoxon's rank sum test.Results: The median age at which cataract surgery was performed was 58 (IQR: 47–65) years. Etiology of DED was CC in 279, MGD in 255, and SS in 134 eyes. Most (471) eyes underwent phacoemulsification, under peribulbar anesthesia (548) through a temporal clear corneal incision (209) with foldable intraocular lens implantation (417). The overall median LogMAR BCVA improved from 1.1 (IQR: 0.6–2.1) at baseline to 0.3 (IQR: 0.1–0.7) and 0.1 (IQR: 0–0.65) at 1 and 6 weeks (p < 0.0001) post-operatively. The median 6 weeks post-operative BCVA was 0.3, 0.1, and 0.1 in CC, MGD, and SS, respectively, and significantly better than at baseline (p < 0.0001). The leading cause of sub-optimal vision was corneal scarring (44; 9%), and the most common complication was posterior capsular rupture with vitreous loss (23; 3%).Conclusion: Cataract surgery has good visual outcomes in patients with DED, without any disconcerting rate of complications. Pre-existing keratopathy is the main determinant of the extent of post-operative visual recovery.

A Simple, Novel Approach to Capsulorhexis Formation in the Setting of A Mature Cataract and Miotic Pupil.

PurposeTo report a simple, effective technique for surgeons creating a capsulorhexis in patients with pupillary miosis and a dense, mature cataract.MethodsA single center, two-year retrospective chart review examined 1408 phacoemulsification cataract surgeries. The criteria for inclusion involved a dense, mature cataract and a pupil that was unresponsive to pharmacologic dilation preoperatively. A standardized technique was used for all cases consisting of a 1mm corneal paracentesis and 2.4mm temporal clear corneal incision. Synecholysis was performed if present, followed by the insertion of a 6.25mm malyugin ring under cohesive viscoelastic. The cohesive viscoelastic was removed via the irrigation aspiration tip. The paracentesis was sealed with a small amount of viscoelastic and an air bubble was placed in the anterior chamber. The anterior capsule was then painted with trypan blue. The air bubble and trypan blue were then replaced by a dispersive viscoelastic. Curvolinear capsulorrhexis was performed followed by standard phacoemulsion.ResultsNine patients ranging from 76 ± 12 years (mean ± standard deviation) met the criteria with a 4+ NS (n=5), white mature (n=3), or deep brunescent (n=1) cataract and 3mm pupil preoperatively. Pupillary miosis was caused by posterior synechia in 44.5% of the cases followed by pharmacologic interactions from tamsulosin and donepezil in 22.25% of cases respectively. One case involved idiopathic miosis likely from aging. Capsulorhexis formation was successful in all cases with no capsular tear, vitreous loss, or conversion to extracapsular cataract extraction (ECCE). However, one case had cortex retention requiring a second procedure for removal.ConclusionDense, mature cataracts and small pupils both compromise the view for the surgeon and may be significant risk factors for training ophthalmologists. Thus, good visualization of the anterior capsule and peripheral nucleus with our simple technique facilitates a reliable capsulorhexis, potentially limiting the risk of complications for ophthalmic surgeons.

Comparative study of astigmatic outcomes and incisional integrity in temporal clear corneal incision and superior scleral incision phacoemulsification surgery

Introduction: Cataract surgery now, is not just rehabilitative surgery but therapeutic also, as patient wants to be ridden off glasses. Surgically induced astigmatism (SIA) is the cause of poor post-operative vision even af ter uneventful cataract surgery. Aims and Methodology: The aim of study was to compare the astigmatic outcomes and incision integrity in 5.5mm temporal clear corneal incision (TCCI) and superior scleral incision (SSI) in phacoemulsification surgery. A total of 200 eyes were included. Cases were randomly divided in two groups. Group A underwent phacoemulsification with TCCI and Group B with SSI, of 5.5mm length. Patients were followed up on post operative day (POD)1,8,40,90,180 Postoperative astigmatism was recorded by keratometry, SIA was analyzed by SIA Software and incision integrity observed by slit lamp examination. Results: Mean Post-operative astigmatism in TCCI group was 0.90, 0.87, 0.79, 0.75, 0.73D on POD 1, 8, 40, 90, 180 respectively, and that in SSI group was 1.43, 1.37, 1.28, 1.24, 1.24D. It was low in TCCI group and statistically significant. Mean SIA in group A was 1.13(0.59), 1.15(0.5), 0.99(0.42), 0.92(0.44), 0.90(0.46) on POD1, 8, 40, 90 and180. The change from POD1 to 40 was significant and there was no further significant change in SIA upto 6months. In group B, SIA was 0.9 2(0.48), 0.92(0.39), 0.80(0.34), 0.75(0.30) and 0.76(0.36) on POD1, 8, 40, 90 and 180. The change from 1st to 40th day was significant and there was mild decrease in SIA on POD 90 and POD 180 but not significant compared to POD 40. Conclusion: Though SIA was high and statistically significant in TCCI group but postoperative astigmatism was less and statistically significant. There was significant WTR shift in postoperative astigmatism in TCCI group and ATR in SSI group. Large incision size of upto 5.5mm clear corneal incision can have self-sealing properties hence dismissing the use of suture. Keywords: Astigmatic outcomes Incision integrity, Postoperati

Tomographic analysis of anterior and posterior surgically induced astigmatism after 2.2 mm temporal clear corneal incisions in femtosecond laser–assisted cataract surgery

To evaluate surgically induced astigmatism (SIA) of temporal clear corneal incisions (CCIs) on anterior and posterior corneal curvature after femtosecond laser-assisted cataract surgery (FLACS) using Scheimpflug tomographic measurements. Department of Ophthalmology, Goethe University, Frankfurt am Main, Germany. Prospective interventional case series. This study enrolled patients who underwent FLACS from June 2013 to July 2014. All eyes were measured with a Pentacam HR preoperatively and at 1month and 3months postoperatively, had preoperative total corneal refractive power (TCRP) astigmatism (CATCRP) of 0.50 diopters (D) or less, and received a temporal 2.2mm incision at 0 degrees and 180 degrees. Vector analysis, using the Holladay-Cravy-Koch formula and the Alpins method, determined astigmatic changes in anterior corneal astigmatism (CAant), posterior corneal astigmatism (CApost), and CATCRP. Student t and Wilcoxon tests were performed. A P value less than 0.05 was considered statistically significant. This study comprised 53 eyes of 38 patients. At 3months postoperatively, the CAant, CApost, and CATCRP were significantly higher compared with the preoperative values (P=.015, P=.007, P=.008, respectively); however, CApost and CATCRP were significantly lower compared with the limit of 0.50 D (P<.001, P=.01, respectively), whereas CAant was not (P=.11). The mean SIA of CAant, CApost, and CATCRP was 0.25 D ± 0.15 (SD), 0.16±0.11 D, and 0.28±0.17 D, respectively. The angle of error was high (-1.98±52.95 degrees, 1.64±51.27 degrees, and -1.72±48.79 degrees, respectively). Femtosecond laser temporal CCIs induce minimal astigmatism in CAant, CApost, and CATCRP, but can be evaluated statistically as astigmatically neutral.

A Comparative Study of 5.5mm Temporal Sclerocorneal Manual Small Incision Cataract Surgery Versus 5.5mm Temporal Clear Corneal Extended-incision Phacoemulsification with Implantation of a 5.25mm Rigid pmma Intraocular lens in the Bag

Objective: Aim of the study is to Compare the astigmatism induced by a reduced temporal sclerocorneal tunnel incision manual small incision cataract surgery with an extended temporal clear corneal Phacoemulsification of similar width . Methods: A Prospective, randomised controlled study was carried out in 224 selected patients who were again divided into two groups - Group A (112 patients) and Group B (112 patients). Group A patients underwent temporal manual small incision cataract surgery with a 5.5 mm sclerocorneal incision and Group B underwent phacoemulsification by a 2.8 mm clear corneal temporal incision which was extended to 5.5 mm before IOL implantation. In both groups, a 5.25 mm rigid PMMA IOL was implanted in the bag. UCVA and BCVA of both group of patients was quantified and analyzed at 1 week and at 6 weeks Observation: It was seen that the mean surgically Induced astigmatism in group A (N=112) was 0.5625D , which was slightly lesser than that in Group B (N=112) which was 0.65D, although the p-value of 0.26 indicated that there was statistically no significant difference in visual outcomes between the two groups of patients. Here, a p-value of &lt; 0.05 was considered statistically significant. Conclusion: In Skilled and Safe hands, refractive outcomes following performing a 5.5mm temporal sclerocorneal frown-incision manual small incision cataract surgery and a phacoemulsification procedure by a 2.8mm temporal clear corneal incision extended to 5.5mm for implanting a 5.25mm rigid PMMA IOL , are comparable.

Evaluation of semi-preloaded intraocular lens delivery system

Purpose: In this study, we aimed to evaluate the single surgeon experience of semi-preloaded intraocular lens (IOL) delivery system. Methods: Phacoemulsification was performed under topical anesthesia by temporal clear corneal incision. CT Lucia hydrophobic IOL was injected through semi- preloaded IOL system in the capsular bag. Two hundred patients (200 eyes) were included in the study. The main outcome measures were ease of implantation, intraoperative and postoperative complications, postoperative centration, and visual acuity. Data on successful implantation and complications were collected prospectively. Results: Correct IOL delivery was achieved in 193 out of 200 patients (96.5%). Four patients (2%) required intrawound rotation of the injector to place the leading haptic in the capsular bag. Two patients (1%) had anteroposterior rotation of the IOL and one patient (0.5%) had total posterior rotation of IOL. Other problems noted were trapped trailing haptic (n=2,1%), improper loading of IOL (n=3,1.5%) and stretch marks on the optic of IOL (n=4,2%). None of the patients had iris trauma or posterior capsular rupture during the implantation and manipulation of the IOL. The mean incision size after completion of implantation of IOL was 2.82 mm (+ 0.02), which achieved sutureless closure. None of the patients developed postoperative infection. Conclusion: Implantation of CT Lucia 601 PY IOL with the semi preloaded system led to minor complications and gave satisfactory visual results.

Architecture evaluation of the main clear corneal incisions in femtosecond laser-assisted cataract surgery by optical coherence tomography imaging.

PurposeTo assess the stability and reliability of femtosecond laser-assisted cataract surgery (FLACS) incisions design and dimensions using anterior segment optical coherence tomography (AS-OCT) imaging.SettingRenato Ambrósio Ophthalmologic Study Center from Hospital Oftalmológico de Brasília, Brasília, Brazil.DesignProspective nonrandomized controlled case series.MethodsEyes undergoing FLACS with triplanar main temporal clear corneal incision (CCI) were evaluated at the end of the case. Eyes that required any incision hydration, surgical complications or lacked follow-up were excluded. The AS-OCT was performed after femtosecond delivery; at the end of the case; at 1 day and at 30 days after surgery. Data of pachymetry, endothelial and epithelial gaps, Descemet detachment and CCI architecture were compared.ResultsEleven eyes from 11 patients completed follow-up. Corneal thickness was statistically different between after femtosecond delivery and the end of the case (P-value <0.05), but without difference compared to 30 days evaluation. There was an increase of Descemet detachments (P-value <0.05) and endothelial gaps (P-value =0.0133) at the end of the case compared to post-femtosecond delivery. As for the architecture of the CCI, significant difference was found between the parameters of entry angle and exit angle measured with AS-OCT and the programmed.ConclusionThe AS-OCT was capable of visualizing changes in the cornea at the CCI. Despite the stress caused by manipulation, results indicated good stability of incision and reproducibility of tunnel length.SynopsisDifference of corneal thickness at the CCI between after femtosecond and after phacoemulsification measurements (P-value <0.05), with increase of endothelial gaps (P-value =0.0133) and Descemet detachments (P-value <0.05).

Corneal shape changes of the total and posterior cornea after temporal versus nasal clear corneal incision cataract surgery

AimTo compare changes in the shape and astigmatism of the total and posterior cornea between eyes with a nasal clear corneal incision (CCI) and eyes with a temporal CCI in...

Prediction of surgically induced astigmatism in manual and femtosecond laser-assisted clear corneal incisions.

To assess the surgically induced astigmatism with femtosecond laser-assisted and manual temporal clear corneal incisions and to evaluate the performance of a model for prediction of the surgically induced astigmatism based on the preoperative corneal astigmatism. Clinical data of 104 right eyes and 104 left eyes undergoing cataract surgery, 52 with manual incisions and 52 with femtosecond laser-assisted incisions in each eye group, were extracted and revised retrospectively. In all cases, manual incisions were 2.2 mm width and femtosecond incisions were 2.5 mm width, both at temporal location. A predictive model of the surgically induced astigmatism was obtained by means of simple linear regression analyses. Mean surgically induced astigmatisms for right eyes were 0.14D@65° (manual) and 0.24D@92° (femtosecond) (p > 0.05) and for left eyes, 0.15D@101° (manual) and 0.19D@104° (femtosecond) (p > 0.05). The orthogonal components of the surgically induced astigmatism (XSIA, YSIA) were significantly correlated (p < 0.05) with the preoperative orthogonal components of corneal astigmatism (Xpreop, Ypreop) (r = -0.29 for X and r = -0.1 for Y). The preoperative astigmatism explained 8% of the variability of the XSIA and 3% of the variability of YSIA. The postoperative corneal astigmatism prediction was not improved by the surgically induced astigmatism obtained from the model in comparison with the simple vector subtraction of the mean surgically induced astigmatism. Temporal incisions induce similar astigmatism either for manual or for femtosecond procedures. This can be clinically negligible for being considered for toric intraocular lens calculation due to the great standard deviation in comparison with the mean. The usefulness of the prediction model should be confirmed in patients with high preoperative corneal astigmatism.

Changes in shape and astigmatism of total, anterior, and posterior cornea after long versus short clear corneal incision cataract surgery

To compare changes in the shape and astigmatism of the total, anterior, and posterior cornea between eyes with long-length clear corneal incisions (CCIs) and eyes with short-length CCIs in cataract surgery. Hayashi Eye Hospital, Fukuoka, Japan. Prospective case series. Both eyes of patients having phacoemulsification with temporal CCIs were randomized to have a long-length (≥1.75mm) or short-length (<1.75mm) CCI. Corneal astigmatic changes were decomposed to vertical/horizontal (Jackson cross-cylinder, axes at 180 degrees and 90 degrees [J0]) and oblique changes (Jackson cross-cylinder, axes at 45 degrees and 135 degrees [J45]) using power vector analysis. Corneal shape changes were assessed using the average of the difference map on videokeratography 2days and 2, 4, and 8weeks postoperatively. The mean J0 and J45 values of the total cornea in the 120 eyes evaluated were significantly greater in the long CCI group than in the short CCI group at all follow-ups (P≤.0290). The videokeratography showed a wedge-shaped flattening in the total and anterior cornea and a steepening in the posterior cornea around the CCI 2days postoperatively in both groups. This wound-related flattening of the total and anterior cornea rapidly reduced but persisted until 8weeks, whereas the steepening of the posterior cornea disappeared within 4weeks. These changes extended closer to the central cornea in the long CCI group than in the short CCI group. Corneal astigmatic changes were significantly greater after long CCI than after short CCI. The wound-related shape changes occurred immediately postoperatively but rapidly diminished.

Comparison of refractive and keratometric astigmatism after microincision cataract surgery

To measure the correlation between refractive and keratometric astigmatism after microincision cataract surgery (MICS). Takayanagi Clinic, Kushiro, Hokkaido, Japan. Retrospective case series. This study evaluated patients having phacoemulsification and intraocular lens implantation through a 2.0mm temporal clear corneal incision. Refractive astigmatism and keratometric astigmatism were described by Jackson cross-cylinder with-the-rule (J0) and oblique (J45) components and compared using linear regression analysis. The study comprised 90 eyes of 54 patients. The mean postoperative refractive J0 was -0.29 diopter (D)±0.46 (SD), and the mean postoperative refractive J45 was -0.09±0.24 D. The multivariate model for the J0 component was postoperative J0=0.75×keratometric J0 + 0.21×preoperative J0 - 0.23 (R2=0.85, P<.001). The coefficient of determination of the multivariate model was higher than that of the univariate model (R2=0.82). The regression equation for the J45 component was postoperative J45=0.85×keratometric J45 - 0.03 (R2=0.70, P<.001). Refractive astigmatism and keratometric astigmatism after MICS were strongly correlated.

Effect of different incision sites of phacoemulsification on trabeculectomy bleb function: prospective case-control study

BackgroundThe aim of this study was to compare superior and temporal clear corneal incisions of uneventful phacoemulsification and in-the-bag intraocular lens implantation on intraocular pressure control and the bleb morphology in eyes that have undergone previous successful trabeculectomy.MethodsIn this Prospective case-control study, a total of 100 eyes of 100 patients previously undergone trabeculectomy without antimetabolites, divided into two groups. Group A (temporal group) including 50 patients underwent phacoemulsification with a temporal corneal incision and group B (superior group) including 50 patients underwent phacoemulsification with a superior corneal incision. Comparisons between the two groups were performed after one year of follow-up regarding Intraocular pressure changes, bleb morphology score using the Wuerzburg bleb classification score and any added glaucoma medications.ResultsAt the last visit, the mean intraocular pressure for the temporal group was 17.55 ± 1.47 (p = 0.51) and for the superior group was 16.90 ± 1.71 (p = 0.85); the difference between the two groups was insignificant (p = 0.21). Regarding the bleb morphology, the mean bleb morphology score in the temporal group was 10.50 ± 0.95 (p = 0.19) and for the superior group was 10.20 ± 1.06 (p = 0.01).There was an insignificant difference in the bleb grading morphology regarding both groups (p = 0.35).ConclusionOur study demonstrates that phacoemulsification whether done with a clear temporal or clear superior wound, does not affect intraocular pressure, bleb morphology or function after one year of follow-up in eyes following previous successful trabeculectomy. Furthermore, cataract surgery may be performed safely in eyes with functioning filtering blebs.Trial registrationISRCTN91835217 ‘retrospectively registered’ Date Of registration 6/6/2017

Intraocular lens power calculation for high myopic eyes with cataract: comparison of three formulas

Objective: To compare the accuracy of three different formulas for intraocular lens power calculation in high myopic eyes with cataract and analyze their influencial factors. Methods: One hundred and three high myopic patients of cataract (103 eyes), with average age of 60.2±8.8 years old (39.0-77.0), including 45 male and 54 female and with axial length ≥ 26 mm were enrolled in this retrospective case-series study. All of them underwent routine ocular examination and IOLMastermeasurement preoperatively and then underwent phacoemulsification through temporal clear-corneal incision with implantation of HumanOptic posterior chamber Intraocular lens (IOL). All analyses were conducted using SPSS version 19.0. Repeated-measures analysis of variance was applied to compare the refractive results one month postoperatively with the predicted IOL powers calculated by SRK/T, Holladay 1, or Haigis formula before surgery. The differences were further compared based on different grouping of axial length (AXL), corneal curvature (K) and corneal astigmatism (CA). The accuracies of the three formulas were analyzed using Bland-Altman analyses and the possible error sources of each formula were analyzed using multiple regression model. Results: The majority of patients enrolled had hyperopic shift after cataract surgery. The mean errors (ME) of the three formulas were SRK/T: 0.70±0.89D, Holladay 1: (1.20±0.88) D and Haigis: (0.60±0.88) D; the mean absolute errors (MAE) of the three formulas were (0.81±0.79) D, (1.23±0.84) D and (0.76±0.74) D, respectively. Both ME and MAE of Holladay formula were significantly greater than the other two formulas (F=86.31, P<0.01). Besides, the proportion of patients having a prediction error within 0.50 D was lower in those using Holladay formula (20.4%, 21/103) than the other two (SRK/T: 38.8%, 40/103, χ(2)=8.41, P<0.01, Haigis: 45.6%, 47/103, χ(2)=14.84, P<0.01). Bland-Altman analyses showed that the accuracies of all the three formulas were acceptable in patients of cataract with high myopia in clinical practice. ME and MAE tended to be larger with longer axial length, larger corneal curvature and astigmatism of the patients in all three formulas. However, in eyes with axial length> 30 mm or corneal curvature ≤43.00 D, the MAE of Haigis formula was lower than that of SRK/T formula (F=63.26,63.94, both P<0.01). The prediction error of SRK/T formula was positively correlated with axial length and corneal astigmatism (F=33.97, r=0.66, β=0.48, P<0.01 and β=0.42, P<0.01), while for Holladay and Haigis formulas, in addition to the previous two factors, the errors were also positively correlated with mean corneal curvature (Holladay 1: F=31.26, r=0.72, AXL: β=0.52, P<0.01, K: β=0.20, P<0.05 and CA: β=0.37, P<0.01; Haigis: F=30.96, r=0.72, AXL: β=0.33, P<0.01, K: β=0.40, P<0.01 and CA: β=0.37, P<0.01). Conclusions: In the selection of IOL formula for high myopic patients with cataract, Haigis or SRK/T would reduce the prediction error and serve as the more accurate formulas than Holladay 1. Haigis formula may be more accurate than SRK/T formula in case of AXL>30 mm or K≤43.00 D. (Chin J Ophthalmol, 2017, 53: 260-265).

A comparison of three different corneal marking methods used to determine cyclotorsion in the horizontal meridian.

During toric intraocular lens (IOL) implantation, surgeons must take particular care to ensure that inaccurate preoperative measurement and intraoperative misalignment do not cause unexpected postoperative residual astigmatism. This retrospective, comparative case series study aimed to analyze the rotational deviation, or cyclotorsion, of three corneal marking methods: VERION digital marker (VDM; reference), horizontal slit beam marking (HSBM), and subjective direct visual marking (SDVM) on the table (using a bevel knife tip). Subjects included 81 eyes of 61 patients (mean age: 65.70±13.14 years; range: 32–91 years) undergoing scheduled cataract surgery. A preoperative reference image was taken of each eye. Subsequently, a slit lamp with the light beam turned to the horizontal meridian was used to align the seated patient’s head, and two reference marks were placed at the 3- and 9-o’clock positions of the corneal limbus using a 27-gauge needle and marking pen (HSBM). Upon transfer to the surgical table, the VDM was used to display a real-time dial scale on the patient’s eye, with the entrance of the temporal clear corneal incision (CCI) at 0° (horizontal meridian). Simultaneously, a bevel knife tip was used to create a marker based on the surgeon’s visual determination of the temporal 0° point (SDVM). We used the VDM to quantitatively evaluate the accuracy of axis alignment via deviation from the horizontal reference meridian. Compared with the reference meridian, the SDVM (−3.46°±7.32°, range: −18° to 13°) exhibited greater average relative cyclotorsion versus the HSBM (0.41°±4.92°, range: −10° to 10°). Furthermore, the mean average misalignment was significantly less in the HSBM group versus the SDVM group (t=4.179, P<0.001). The VDM is likely a reliable marking method, similar to the HSBM. In contrast, the SDVM is not entirely reliable. The VDM usage may prevent inaccurate preoperative manual marking during toric IOL implantation.

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 Opposite Clear Corneal Incision in Controlling Astigmatism in Cataract Patients Undergoing Phacoemulsification Surgery

Aim: To evaluate the role of clear corneal incision combined with opposite clear corneal incision in controlling astigmatism in patients undergoing phacoemulsification surgery for cataract. Design: Prospective clinical study. Methods: 45 consecutive patients planned for phacoemulsification were divided into three equal groups of fifteen patients each: Group 1 presenting without corneal astigmatism, Group 2 having WTR (with-the-rule) and Group 3 having ATR (against-the-rule) astigmatism. All underwent phacoemulsification through 2.8mm clear corneal incision. In Group 1 the temporal clear corneal incision (CCI) was enlarged to 3.2mm before IOL insertion along with 2.2mm superior CCI to neutralise the astigmatism induced by main cataract incision. In Group 2 the superior CCI was enlarged to 3.2mm before IOL insertion, followed by 3.2mm inferior opposite CCI. In Group 3 the temporal CCI was enlarged to 3.2mm before IOL insertion followed by 3.2mm nasal opposite CCI. Results: In Group 1, the overall mean postoperative astigmatism observed was 0.28 ± 0.2D WTR, with 4 out of 15 patients (26.66%) continuing to have nil astigmatism. In Group 2, the mean postoperative astigmatism was reduced from 1.16 ± 0.32D WTR preoperatively, to 0.46 ± 0.28D WTR at 3 months postoperatively. In Group 3, the preoperative astigmatism of -1.25 ± 0.32DATR reduced to -0.38 ± 0.31D ATR, 3 months postoperatively. The reduction in astigmatism was statistically significant in both WTR and ATR astigmatism groups (p < 0.001). Conclusion: More than 50% reduction in astigmatism was achieved in both groups with astigmatism. Thus opposite clear corneal incision (OCCI) is a simple, predictable, safe and effective procedure in reducing mild to moderate preexisting corneal astigmatism in cataract surgery.

Comparison of preoperative and postoperative corneal astigmatism after phacoemulsification through a 2.8mm clear corneal temporal incision

Comparison of preoperative and postoperative corneal astigmatism after phacoemulsification through a 2.8mm clear corneal temporal incision

Phaco-emulsification in completely vitrectomized eyes: Intraoperative analysis of modified phaco sleeve.

Purpose:The purpose was to evaluate the results of modified sleeve in phacoemulsification of cataract in completely vitrectomised eyes,Materials and Methods:Twenty-five previously completely vitrectomized eyes of 23 patients having visually significant cataract were included. After through evaluation they underwent phaco-emulsification by phaco chop with a modified sleeve via temporal clear corneal incision. The modified sleeve was made by creating a small round port of approximate 1 × 1 mm size at the proximate end of the sleeve in line with the already existing ports. This port faced the posterior capsule while performing phacoemulsification. Patients were observed for any intraoperative complications.Result:The most common indication for pars plana vitrectomy in our study group was vitreous hemorrhage due to diabetic retinopathy [13 out of 25 eyes (52%)]. Intraoperative findings included miosis [seen in 3 (12%) eyes] and posterior capsular plaque [seen in 2(8%) eyes]. No other significant intraoperative complications (posterior capsular tear, dropped nucleus) were observed. Average effective phaco time was 33 sec. (±15.11).Conclusion:Though cataract surgery in postvitrectomized eyes is a challenging situation, modified sleeve prevents anterior chamber fluctuation and avoids complications arising out of it, making the surgery safe.