Wound stability and surgically induced corneal astigmatism after transconjunctival single-plane sclerocorneal incision cataract surgery

High-risk factors for zonular complications during cataract surgery in eyes with pseudoexfoliation syndrome

AIMS

To predict high-risk factors for zonular complications during cataract surgery due to pre-existing severe zonular dehiscence in eyes with pseudoexfoliation (PXF) syndrome.

METHODS

315 eyes of 315 consecutive patients with PXF scheduled for phacoemulsification surgery underwent preoperative examination of various ocular parameters using an anterior segment-optical coherence tomography and other devices. When zonular complications occurred during surgery due to zonular dehiscence, scleral fixation of the intraocular lens (IOL) or implantation of a capsular tension ring (CTR) was performed. High-risk factors for these intraoperative zonular complications were examined using classification-tree and logistic regression analyses.

RESULTS

Of the 315 eyes, 31 (9.84%) underwent scleral IOL fixation or CTR implantation. High-risk factors identified by classification-tree analysis were a small pupillary diameter after mydriasis <6.30 mm, a shallow anterior chamber depth <2.074 mm and lens decentration >0.260 mm. Based on exact logistic regression analysis, the OR was 4.81-fold higher for eyes with poor mydriasis than for eyes without poor mydriasis (p=0.006, 95% CI 1.49 to 18.23), 23.99-fold higher for eyes with poor mydriasis and a shallow anterior chamber (p<0.001, 5.92 to 109.02) and 287.39-fold higher for eyes with poor mydriasis, a shallow chamber and great lens decentration (p<0.001, 50.46 to infinity).

CONCLUSION

In eyes with PXF, high-risk factors for zonular complications during cataract surgery due to pre-existing severe zonular dehiscence were poor mydriasis, shallow anterior chamber and large lens decentration, suggesting the importance of evaluating these conditions preoperatively.

Prediction of postoperative refractive astigmatism before toric intraocular lens implantation

Background

To 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.

Methods

Prospective, 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.

Results

The regression model for the J0 component was \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ Postoperative\kern0.34em refractive\kern0.2em J0=1.05\times Coneal\kern0.2em J0-0.14 $$\end{document}PostoperativerefractiveJ0=1.05×ConealJ0−0.14 (R² = 0.96, P < 0.001). The model for the J45 component was \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ Postoperative\kern0.34em refractive\kern0.2em J45=0.68\times Coneal\kern0.2em J45+0.19\times Preoperative\kern0.34em refractive\kern0.2em J45-0.06 $$\end{document}PostoperativerefractiveJ45=0.68×ConealJ45+0.19×PreoperativerefractiveJ45−0.06 (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).

Conclusions

Refractive 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.

Individualized Corneal Patching for Treatment of Corneal Trauma Combined with Tissue Defects

Aim

To evaluate the efficacy of individualized corneal patching using a minimal graft for corneal trauma combined with tissue defects.

Methods

Fifteen eyes (15 patients) were enrolled in this study, including 8 eyes with corneal perforation induced by removal of metal foreign bodies, 5 eyes with corneal laceration resulting from metal trauma, and 2 eyes with pencil injuries to the cornea. The size, shape, and depth of the tissue defects were assessed. For corneal perforation or irregular tissue defects, if the diameter or length was ≥3.0 mm, traditional penetrating keratoplasty (PK) or lamellar keratoplasty (LK) was adopted; if the diameter or length was ＜3.0 mm, a conical or irregular patch consistent with the defects was used. The visual acuity, corneal status, and postoperative complications were observed during the follow-up.

Results

The diameter of corneal perforations was 1.0 mm in 2 eyes, 1.5 mm in 1 eye, 2.0 mm in 4 eyes, and 3.5 mm in 1 eye. During their PK procedures, a conical corneal graft was used in 7 eyes, while a traditional cylindrical graft was used in 1 eye. The other 7 eyes had corneal trauma combined with irregular tissue defects, which were full-thickness corneal defects in 5 eyes and lamellar defects in 2 eyes, all less than 3.0 mm in length. Thus, five eyes received PK, and 2 eyes received LK using an irregular wedge-shaped patch. The visual acuity increased greatly postoperatively, with mild corneal astigmatism. None of the patients developed immune rejection.

Conclusion

Individualized corneal patching with a minimal graft can save corneal materials, relieve corneal scars, gain a good visual prognosis, and avoid immune rejection in the treatment of corneal trauma combined with tissue defects.

Changes in corneal astigmatism during 20 years after cataract surgery

PURPOSE

To examine how corneal astigmatism changes with age over 20 years after cataract surgery and to assess whether the changes differ from those in eyes that did not have surgery.

SETTING

Hayashi Eye Hospital, Fukuoka, Japan.

DESIGN

Retrospective case study.

METHODS

Using an autokeratometer, corneal astigmatism was measured preoperatively, at baseline (the day the surgically induced astigmatism stabilized), and 10 years and 20 years after baseline. The change in corneal astigmatism between baseline and 10 years, 10 years and 20 years, and baseline and 20 years was determined using power vector analysis and compared between the time intervals and between groups.

RESULTS

The study assessed 74 eyes that had phacoemulsification with a horizontal scleral incision more than 21 years ago (surgery group) and 68 eyes that did not have surgery (no-surgery group). The mean vertical/horizontal change in corneal astigmatism (J0) between baseline and 20 years was -0.64 diopter (D) in the surgery group and -0.49 D in the no-surgery group. The oblique change (J45) was -0.03 D in the surgery group and 0.07 D in the no-surgery group. Using multivariate comparison, the mean J0 and J45 values were not significantly different between baseline and 10 years or between 10 years and 20 years in both groups (P ≥ .2350). The J0 and J45 values were not significantly different between the 2 groups at any time interval (P ≥ .1331).

CONCLUSIONS

Corneal astigmatism continues to change toward against-the-rule astigmatism over 20 years after cataract surgery. This change was similar in eyes that did not have surgery.

Endophthalmitis after cataract surgery: Effect of behind-the-lens washout

PURPOSE

To analyze the outcomes of cataract surgery with emphasis on the relationship between surgery-related factors and the incidence of postoperative infectious endophthalmitis.

SETTING

Ninety-three surgical sites in Japan.

DESIGN

Prospective case series.

METHODS

Eyes that were scheduled to have cataract surgery from January 20 to September 30, 2014, were included. Phacoemulsification and implantation of a single-piece hydrophobic acrylic foldable intraocular lens (IOL) were performed. Patients were followed for 2 months.

RESULTS

Of the 9720 eyes enrolled, 9100 (93.6%) completed a 2-month follow-up. Three cases (0.033%) developed infectious endophthalmitis (95% confidence interval [CI], 0.000-0.070). The incidence of endophthalmitis was significantly associated with the removal method of ophthalmic viscosurgical devices (OVDs) after IOL implantation. The incidences of endophthalmitis in cases with and without the behind-the-lens technique were 0% (0/6147; 95% CI, 0%) and 0.084% (3/3570; 95% CI, 0.000-0.179), respectively, with a significant difference between them (P = .050, Fisher exact test). The incidence of infectious endophthalmitis did not correlate with any other patient-related and surgery-related factors.

CONCLUSION

The behind-the-lens technique to wash and clear the capsular bag for OVD removal significantly reduced the incidence of infectious endophthalmitis.

Axial Length Shortening After Cataract Surgery: New Approach to Solve the Question

Purpose

To check if optical biometry can detect eventual corneal power (Km) and axial length (AL) cataract surgery-related changes that could influence the refractive outcome.

Methods

Patients scheduled for sequential bilateral cataract surgery between January and September 2017 were included in the present study. One hundred ninety-six eyes of 98 patients (48 males) were selected. Before surgery of the first eye, patients underwent a complete ophthalmic examination, including IOLMaster biometry; the same evaluations were repeated in both eyes the day before the fellow eye cataract surgery, performed at least 2 months after the first one. The differences in Km and AL in the first operated eyes were evaluated, and the fellow eyes were used as controls.

Results

Km differences in the operated eyes ranged from −1.97 to +0.98 diopter (D) (mean = −0.02 ± 0.36 D) (P = 0.89); in the nonoperated eyes they ranged from −0.6 to +0.7 D (mean = 0 ± 0.20 D) (P = 0.91). The AL differences (pseudophakic option) in the operated eyes ranged from −0.35 to +0.15 mm (mean = −0.10 ± 0.08 mm) (P < 0.001); with the aphakic option they ranged from −0.24 to + 0.26 mm (mean = 0.01 ± 0.08 mm) (P= 0.38). In the nonoperated eyes, the AL differences ranged from −0.04 to +0.06 mm (mean= 0 ± 0.02 mm) (P = 0.02).

Conclusions

The modern phaco-technique seems not to induce changes in Km and AL, supporting the hypothesis that the differences in AL are due to an incorrect estimation in pseudophakic eyes.

Translational Relevance

The results of our study may improve the AL measurements in pseudophakic eyes.

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

Aim

To 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 cataract surgery.

Methods

The left eyes of 100 patients undergoing phacoemulsification were randomly assigned to undergo a 2.4 mm nasal (nasal CCI group) or temporal CCI (temporal CCI group). Corneal astigmatic changes were compared between groups using power vector analysis, and corneal shape changes were compared using videokeratography maps at 2 days, and at 2, 4 and 8 weeks postoperatively.

Results

The mean J₀ and J₄₅ values of the total cornea were significantly greater in the nasal CCI group than in the temporal CCI group at 2 and 4 weeks postoperatively (p≤0.0392), but did not differ significantly between groups at 2 days and 8 weeks. The videokeratography maps revealed a wedge-shaped flattening in the total cornea and a steepening in the posterior cornea around the CCIs in both groups at 2 days postoperatively; those were more prominent in the nasal CCI group than in the temporal CCI group. The wound-related changes diminished by 8 weeks postoperatively in the total and posterior cornea, and were not markedly different between groups at 8 weeks postoperatively.

Conclusion

Corneal shape and astigmatic changes were comparable between groups at 8 weeks postoperatively, although the changes were greater after nasal CCI than after temporal CCI in the early postoperative periods, indicating that nasal or temporal CCI can be selected based on the surgeon’s preference.

Intraocular pressure elevation after cataract surgery and its prevention by oral acetazolamide in eyes with pseudoexfoliation syndrome

PURPOSE

To examine whether intraocular pressure (IOP) increases immediately after cataract surgery in eyes with pseudoexfoliation (PXF) syndrome and to assess whether orally administered acetazolamide can prevent the IOP elevation.

SETTING

Hayashi Eye Hospital, Fukuoka, Japan.

DESIGN

Prospective case series.

METHODS

Patients with PXF syndrome scheduled for phacoemulsification were randomly assigned to 1 of 3 groups: (1) oral acetazolamide administered 1 hour preoperatively (preoperative administration group), (2) administered 3 hours postoperatively (postoperative administration group), and (3) not administered (no administration group). The IOP was measured using a rebound tonometer 1 hour preoperatively, upon completion of surgery, and at 1, 3, 5, 7, and 24 hours postoperatively.

RESULTS

The study comprised 96 patients (96 eyes). The mean IOP increased at 3, 5, and 7 hours postoperatively in all groups. At 1 hour and 3 hours postoperatively, the IOP was significantly lower in the preoperative administration group than in the postoperative group and no administration group (P ≤ .001). At 5, 7, and 24 hours postoperatively, the IOP was significantly lower in the preoperative group and postoperative administration group than in the no administration group (P ≤. 045). An IOP spike higher than 25 mm Hg occurred less frequently in the preoperative administration group than in the postoperative administration group and the no administration group (P = .038).

CONCLUSIONS

Intraocular pressure increased at 3, 5, and 7 hours after cataract surgery in eyes with PXF syndrome. Oral acetazolamide administered 1 hour preoperatively reduced the IOP elevation throughout the 24-hour follow-up; acetazolamide administered 3 hours postoperatively reduced the elevation at 5 hours postoperatively and thereafter.

Binocular visual function of myopic pseudophakic monovision

PURPOSE

To compare binocular visual function of myopic pseudophakic patients with myopic monovision to patients without monovision.

STUDY DESIGN

Randomized comparative study METHODS: Sixty patients were randomized to one of two groups: patients whose refraction was targeted to -2.75 diopters (D) in the dominant eye and -1.75D in the nondominant eye (myopic monovision group), and patients whose refraction was targeted to -2.75D bilaterally (non-monovision group). Binocular uncorrected and corrected visual acuity at various distances was measured using an all-distance vision tester, and contrast visual acuity and near stereoacuity were examined.

RESULTS

In the myopic monovision group mean refraction was -2.74D in the dominant eyes and -1.94D in the nondominant eyes, and in the non-monovision group it was -2.96D bilaterally. Mean binocular uncorrected distance (UDVA) and intermediate visual acuity (UIVA) from 0.5 m to 5.0 m were significantly better in the myopic monovision group than in the non-monovision group (P≤ 0.0134), while binocular uncorrected near visual acuity (UNVA) at 0.3 m did not differ significantly between groups. The distribution of UIVA and UDVA was significantly better in the myopic monovision group (P≤ 0.0035). Corrected visual acuity at any distance, photopic and mesopic contrast visual acuity, and stereoacuity did not differ significantly between groups.

CONCLUSION

Patients with myopic monovision exhibited significantly better binocular UIVA and UDVA than those without monovision, while UNVA, corrected visual acuity, contrast sensitivity, and stereoacuity were comparable between groups, suggesting that this method is useful for patients who want to see near and intermediate distances without spectacles.

Different-sized incisions for phacoemulsification in age-related cataract

BACKGROUND

Age-related cataract is the principal cause of blindness and visual impairment in the world. Phacoemulsification is the main surgical procedure used to treat cataract. The comparative effectiveness and safety of different-sized incisions for phacoemulsification has not been determined.

OBJECTIVES

The aim of this systematic review was to assess the effectiveness and safety of smaller versus larger incisions for phacoemulsification in age-related cataract. The primary outcome of this review was surgically induced astigmatism at three months after surgery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 10), MEDLINE Ovid (1946 to 28 October 2016), Embase Ovid (1947 to 28 October 2016), PubMed (1948 to 28 October 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 28 October 2016), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com; last searched 13 May 2013), ClinicalTrials.gov (www.clinicaltrials.gov; searched 28 October 2016), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp; searched 28 October 2016). We did not use any date or language restrictions in the electronic searches for trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing different-sized incisions in people with age-related cataract undergoing phacoemulsification.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 26 RCTs with a total of 2737 participants (3120 eyes). These trials were conducted in Bosnia and Herzegovina, China, France, India, Italy, Korea, Spain, Switzerland, and Turkey. Half of the 26 trials were conducted in China. We judged all trials as mostly at unclear to low risk of bias. The included RCTs compared four different-sized incisions:<= 1.5 mm, 1.8 mm, 2.2 mm, and approximately 3.0 mm. These incisions were performed using three different techniques: coaxial and biaxial microincision phacoemulsification (C-MICS and B-MICS) and standard phacoemulsification. Not all studies provided data in a form that could be included in this review. Five studies had three arms.Fifteen trials compared C-MICS (2.2 mm) with standard phacoemulsification (about 3.0 mm). Very low-certainty evidence suggested less surgically induced astigmatism in the C-MICS group at three months compared with standard phacoemulsification (mean difference (MD) -0.19 diopters (D), 95% confidence interval (CI) -0.30 to -0.09; 996 eyes; 8 RCTs). There was low-certainty evidence that both groups achieved similar best-corrected visual acuity (MD 0.00 logMAR, 95% CI -0.02 to 0.02; 242 eyes; 3 RCTs). There was low-certainty evidence of little or no difference in endothelial cell loss and central corneal thickness comparing C-MICS with standard phacoemulsification (MD -7.23 cells/mm², 95% CI -78.66 to 64.20; 596 eyes; 4 RCTs) and (MD -0.68 μm, 95% CI -3.26 to 1.90; 487 eyes; 5 RCTs).Nine trials compared C-MICS (1.8 mm) with standard phacoemulsification (about 3.0 mm). Very low-certainty evidence suggested less astigmatism at three months in the C-MICS group compared with standard phacoemulsification group (MD -0.23 D, 95% CI -0.34 to -0.13; 561 eyes; 5 RCTs). Low-certainty evidence suggested little or no difference in best-corrected visual acuity, endothelial cell loss, and central corneal thickness in the two groups at three months (MD -0.02 logMAR, 95% CI -0.03 to -0.00; 192 eyes; 3 RCTs), (MD 7.56 cells/mm², 95% CI -67.65 to 82.77; 380 eyes; 5 RCTs), and (MD -1.52 μm, 95% CI -6.29 to 3.25; 245 eyes; 3 RCTs).Six studies compared C-MICS (1.8 mm) with C-MICS (2.2 mm). There was low-certainty evidence that astigmatism, visual acuity, and central corneal thickness were similar in the two groups at three months (MD 0.04 D, 95% CI -0.09 to 0.16; 259 eyes; 3 RCTs), (MD 0.01 logMAR, 95% CI -0.01 to 0.04; 200 eyes; 3 RCTs), and (MD 0.45 μm, 95% CI -2.70 to 3.60; 100 eyes; 1 RCT). Very low-certainty evidence suggested higher endothelial cell loss in the 1.8 mm group (MD 213.00 cells/mm², 95% CI 11.15 to 414.85; 70 eyes; 1 RCT).Four studies compared B-MICS (<= 1.5 mm) with standard phacoemulsification (about 3.0 mm). Astigmatism was similar in the two groups at three months (MD -0.01 D, 95% CI -0.03 to 0.01; 368 eyes; 2 RCTs; moderate-certainty evidence). There was low-certainty evidence on visual acuity, suggesting little or no difference between the two groups (MD -0.02 logMAR, 95% CI -0.04 to -0.00; 464 eyes; 3 RCTs). Low-certainty evidence on endothelial cell loss and central corneal thickness also suggested little or no difference between the two groups (MD 55.83 cells/mm², 95% CI -34.93 to 146.59; 280 eyes; 1 RCT) and (MD 0.10 μm, 95% CI -14.04 to 14.24; 90 eyes; 1 RCT).None of the trials reported on quality of life. One trial reported that no participants experienced endophthalmitis or posterior capsule rupture; they also reported little or no difference between incision groups regarding corneal edema (risk ratio 1.02, 95% CI 0.40 to 2.63; 362 eyes).

AUTHORS' CONCLUSIONS

Phacoemulsification with smaller incisions was not consistently associated with less surgically induced astigmatism compared with phacoemulsification with larger incisions. Coaxial microincision phacoemulsification may be associated with less astigmatism than standard phacoemulsification, but the difference was small, in the order of 0.2 D, and the evidence was uncertain. Safety outcomes and quality of life were not adequately reported; these should be addressed in future studies.