Recommendations for Senile Cataracts Evidence Base
Developed by Asia-Pacific Center for Evidence-Based Health Care, 2016 Last Searched May 2016
Recommendations for Senile Cataracts Evidence Base
INTRODUCTION
Aside from these next few paragraphs, the rest of the document is the product of the Asia-Pacific Center for Evidence-Based Healthcare. The contents of this report was provided to the CPG Panelists before the conference. It is reproduced here in its entirety with permission of the PAO to provide interested readers and the stakeholders the bases for the deliberations and the final recommendations of the CPG.
The GRADE methodology, the references selected, and the Forest Plots can be independently verified and analyzed. This unprecedented transparency in the development of the CPG on Senile Cataracts emphasizes the Steering Committee’s commitment to eliminating bias and doubt, and, should set the bar for the formulation of future CPGs by the PAO.
HOW TO APPRECIATE THE EVIDENCE BASE
1. Each individual question was searched for evidence until February 29, 2016 and summarized. If possible, the data from several clinical studies were pooled to come up with single estimate or the treatment effect. This was done by conducting a meta-analysis or basing it on an existing meta-analysis.
2. The first 2 sections are guides on how to interpret the results and how the GRADE approach in grading the level of quality of evidence is used.
3. The evidence for each question is presented in 3 parts:
1. Summary of Evidence in simplified text format (including table on the interpretation of the evidence for some questions).
2. GRADE Evidence Tables showing the assessment of the quality of evidence and summary statistics
3. Forest Plots depicting the pooled effect.
I. QUICK GUIDE ON HOW TO INTERPRET THE EVIDENCE
Table 2. Interpreting 95% Confidence Intervals (CIs)
Instructions: When researchers express the effect of treatment using the relative risk reduction, absolute risk reduction, or relative risk, they often give us a range of possibilities rather than a single estimate. This range of possibilities is called a ‘95% Confidence Interval (95% CI)’ to mean ‘we are 95% sure that the true effect of a drug lies in this range’. Go through this tackle box in rows, to discover how helpful 95% CIs are.
¶ In both inconclusive and equivalent results, the 95% CI interval straddles the point of no effect (ARR=0% or RR=1.0). One end reflects the worst possible harm, while the other end reflects the best possible benefit. The only difference is that, in equivalence, either end is close to “no effect” (i.e. any benefit is ignorable and any harm is ignorable too). Consider the ends of the 95% CI to make sure you agree that the benefits and harms are ignorable.
Rc is the rate of the outcomes in the Control group
Rt is the rate of the outcome in the Treatment group
Note: The interpretations in this table only hold if the dichotomous events are expressed as adverse rather than desirable events, e.g. death rather than survival, treatment failure rather that cure, or disease rather than disease-free. When dichotomous outcomes are expressed as desirable events, the interpretation of benefit and harm is reversed. We feel researchers should standardize reporting and use adverse events in order to avoid confusion. Unfortunately, nobody cares what we think.
Table 3. How to interpret forest plots
Instructions: The balloons below label the most important parts of the forest plot. Go through these labels and familiarize yourself with the anatomy of the graph. Once you feel sufficiently familiar with the anatomy, go through the notes below on what the forest plot can signify.
Review : Hypothetical example
Comparison : 01 Gym-based fitness regimen (treatment) vs Home-based fitness regimen (control)
Outcome : 02 Failure to get a modelling contract
II. GRADE Approach in assessing the level of quality of evidence
(GRADE: Grading of Recommendations Assessment, Development and Evaluation; modified from WHO Handbook in Guideline Development, 2014).
These quality ratings apply to the body of evidence assessed for the research question, not to individual studies.
Evidence based on randomized controlled trials is initially given a high-quality rating and evidence from observational studies is given a low-quality rating. The level is then adjusted according to the following criteria:
SUMMARY OF EVIDENCE
Evidence for MSICS versus phacoemulsification for the outcome of good functional vision at 3 months (uncorrected acuity 6/18 or better from 6-8 weeks of follow-up) showed significant benefit in favor of phacoemulsification with a relative risk (RR) of 0.90 (95% CI 0.84, 0.96) based on 3 randomized controlled trials (RCTs).
Other evidence summarized and combined from 13 RCTs1-13 and 3 meta-analysis14-1 6 failed to show significant difference in the following:
1. Good functional vision at 6 months (uncorrected acuity 6/18 or better) based on 1 RCT, with an RR of 1.07 (95% CI 0.91, 1.26).10
2. Good functional vision at 3 months (best-corrected acuity 6/18 to 6/12 or better) based on 6 RCTs, with an RR of 0.99 (95% CI 0.98, 1.01).1-3,5-7
3. Good functional vision at 6 months (best-corrected acuity) based on 1 RCT, with an RR of 1.0 (95% CI 0.94, 1.06).10
4. Poor visual outcome at 3 months (best corrected acuity worse than 6/60), OR 2.48 (95% CI 0.74, 8.28).1-3,5-7
5. Poor visual outcome at 6 months (best-corrected acuity worse than 6/18) based on 1RCT is 1.9% in both groups with a computed RR of 1.0 (95% CI 0.06, 16).10
6. Uncorreced visual acuity in 1 week after surgery, RR 1.0 (95% CI 0.97, 1.03)2,4,9,12,13.
Furthermore neither surgical techniques showed clear benefit in preventing any of the complications such as posterior capsular rupture,1-3,5-14 corneal edema postoperatively,1-3,6-9,11-14 endothelial cell loss,5,7 and astigmatism.2,3,5,7,11
In light of the evidence, it seems that phacoemulsification still has an edge over MSICS in terms of visual acuity improvement. Although astigmatism may be a problem, it has not been clearly established with the current evidence.
Among patients with senile cataracts, phacoemulsification is favored over MSICS due to good functional vision at 3 months with uncorrected visual acuity of 6/18 or better. Adverse events have shown to be insiginificant for both procedures. Level of Evidence: Very Low to Moderate. Strength of Recommendation: Weak.
REFERENCES
1. Cook C, Carrara H, Myer L. Phacoemulsification versus manual small-incision cataract surgery in South Africa. S Afr Med J 2012;102:537-40.
2. Gogate PM, Kulkarni SR, Krishnaiah S, et al. Safety and efficacy of phacoemulsification compared with manual small- incision cataract surgery by a randomized controlled clinical trial: six-week results. Ophthalmology 2005;11 2:869-74.
3. Venkatesh R, Tan CS, Sengupta S, et al. Phacoemulsification versus manual small-incision cataract surgery for white cataract. J Cataract Refract Surg 2010;36:1849-54.
4. Fu JM, Ying TR, Zheng HH. Clinical study of senile cataract surgical treatment. Zhong Guo Xian Dai Yi Sheng 2012;5036- 38.
5. George R, Rupauliha P, Sripriya AV, et al. Comparison of endothelial cell loss and surgically induced astigmatism following conventional extracapsular cataract surgery, manual small-incision surgery and phacoemulsification. Ophthalmic Epidemiol 2005;12:293-7.
6. Ghosh S, Roy I, Biswas PN, et al. Prospective randomized comparative study of macular thickness following phacoemulsification and manual small incision cataract surgery. Acta Ophthalmol 2010;88:e102-6.
7. Gogate P, Ambardekar P, Kulkarni S, et al. Comparison of endothelial cell loss after cataract surgery: phacoemulsification versus manual small-incision cataract surgery: six-week results of a randomized control trial. J Cataract Refractive Surg 2010;36:247-53.
8. Ji Z. Efficacy comparison between small incision ECCE and phacoemulsification surgery in cataract patients. Zhong Guo Yi Shi Jin Xiu Za Zhi 2011;34:26-28.
9. Lin RJ, Li LJ. Study on small-incision sutureless cataract extraction and intraocular lens implantation surgery. Zhong Guo Yi Shi Jin Xiu Za Zhi 2007;30:21-23.
10. Ruit S, Tabin G, Chang D, et al. A prospective randomized clinical trial of phacoemulsification vs manual sutureless small-incision extracapsular cataract surgery in Nepal. Am J Ophthalmol 2007;143:32-8.
11. Singh SK, Winter I, Surin L. Phacoemulsification versus small- incision cataract surgery (SICS): which one is a better surgical option for immature cataract in developing countries?. Nepal J Ophthalmol 2009;1:95-1 00.
12. Zhang L, Liu L. Small-incision sutureless cataract surgery. Yan Wai Shang Zhi Ye Bing Za Zhi 2006;28:346-348.
13. Zhang SH, Liao RB, Cai SH. The clinical efficacy of nuclear techniques broken small-incision cataract surgery. Guang Dong Yi Xue 2011;32:2305-2307.
14. Zi Y, Shou-Zhi H, Zhao-Hui Li. Efficacy comparison between manual small-incision cataract surgery and phacoemulsification in cataract patients: a meta-analysis. Int J Clin Exp Med. 2015;8:8848-8853.
15. Gogate P, Optom JJB, Deshpande S, Naidoo K. Meta-analysis to compare the safety and efficacy of manual small incision cataract surgery and phacoemulsification. Middle East Afr J Ophthalmol 2015;22:362-369.
16. Riaz Y, de Silva SR, Evans JR. Manual small incision cataract surgery (MSICS) with posterior chamber intraocular lens versus phacoemulsification with posterior chamber intraocular lens for age-related cataract. Cochrane Database Syst Rev 2013;10:CD008813.
SUMMARY OF EVIDENCE
These findings were derived from 6 randomized controlled trials (RCT)1- 6 and 1 meta-analysis.7 In the combined analysis, it was noted that good functional vision at 3 months (uncorrected visual acuity and best corrected visual acuity) significantly favored phacoemulsification.1- 4 Good functional vision at 12 months, in terms of uncorrected visual acuity, also significantly favored phacoemulsification.2 However, at 12 months, measured by best corrected visual acuity, the difference between phacoemulsification and ECCE was insignificant.
Poor visual outcome at 3 months, in terms of best corrected acuity of 6/60 or worse, was significantly lower in phacoemulsification.1-3 However, after 12 months, this outcome was insignificant between phacoemulsification and ECCE.
Adverse events or complications that did not show any significant difference between the 2 techniques were capsular rupture,2,3,5 retinal detachment2 and endothelial cell loss.2,3,6 However, posterior capsular opacification,2,5 cystoid macular edema,2,5 and iris prolapse2 are complications that were significantly lower with phacoemulsification
The studies generally had an unclear risk of bias due to poorly reported trial methods and although the quality per outcome ranged from low to moderate, overall quality was deemed low for this question.
DRAFT RECOMMENDATION
Among patients with senile cataracts, phacoemulsification is favored over ECCE because of significant benefit and lower complications. Level of Evidence: Low to Moderate. Strength of Recommendation: Weak.
1. Chee SP, Ti SE, Sivakumar M, Tan DT. Postoperative inflammation: extracapsular cataract extraction versus phacoemulsification. J Cataract Refract Surg 1999;25:1280-5.
2. Bourne RR, Minassian DC, Dart JK, et al. Effect of cataract surgery on the corneal endothelium: modern phacoemulsification compared with extracapsular cataract surgery. Ophthalmology 2004;111 :679-85.
3. George R, Rupauliha P, Sripriya AV, et al. Comparison of endothelial cell loss and surgically induced astigmatism following conventional extracapsular cataract surgery, manual small-incision surgery and phacoemulsification. Ophthalmic Epidemiol 2005;12:293-7.
4. Laurell CG, Zetterstrom C, Philipson B, Syrén-Nordqvist S. Randomized study of the blood-aqueous barrier reaction after phacoemulsification and extracapsular cataract extraction. Acta Ophthalmol Scand 1998;76:573-8.
5. Katsimpris JM, Petropoulos IK, Apostolakis K, Feretis D. Comparing phacoemulsification and extracapsular cataract extraction in eyes with pseudoexfoliation syndrome, small pupil, and phacodonesis. Klin Monbl Augenheilkd. 2004;221:328-33.
6. Díaz-Valle D, Benítez del Castillo Sánchez JM, Castillo A, et al. Endothelial damage with cataract surgery techniques. J Cataract Refract Surg 1998;24:951- 5.
7. de Silva SR, Riaz Y, Evans JR. Phacoemulsification with posterior chamber intraocular lens versus extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens for age-related cataract. Cochrane Database Syst Rev 2014;1:CD008812.
SUMMARY OF EVIDENCE
Evidence from 2 randomized controlled trials (RCTs) showed that there was no significant difference in terms of improvement of visual acuity at 6-8 weeks between MSICS and ECCE with a relative risk (RR) of 1.57 (95% CI 0.88, 2.8) [Figure Q3.1 in Appendix Q3].1,2 However the data presented in these 2 RCTs reporting poor visual outcome were not combined due to difference on how the measurements were made. Both RCTs reported an insignificant difference between the 2 procedures with regards to poor visual outcomes at 6-8 weeks. One study reported an RR of 1.58 (95% CI 0.45,5.0) supporting the insignificant findings.1
Surgically-induced astigmatism was significantly less for MSICS. One study reported a mean induced astigmatism in diopters of 1.77±1.65 for ECCE vs 1.1±0.95 for MSICS, p=0.012.3 In another study, the incidence of astigmatism of ≥2D had a relative risk of 0.49, (95% CI 0.32-0.74) indicating less astigmatism in the MSICS technique.2
Intraoperative and postoperative complications based on 1 RCT, were significantly higher with MSICS, with relative risks of 1.83 (95% CI 1.02-3.26), and 1.38 (95% CI 1.1-1.73), respectively.1 Both intraoperative and postoperative complications reported in the RCT were graded and scored as described by the Oxford Cataract Treatment and Evaluation Team (OCTET). Please refer to Appendix Q3 for the list of complications monitored. This list does not include astigmatism.
There were limited number of studies with issues on allocation and concealment. It was unfortunate that most of the data could not be combined due to differences in reporting of outcomes.
DRAFT RECOMMENDATION
There is still inadequate evidence that MSICS showed improved visual acuity (VA) compared to ECCE. MSICS has less surgically-induced astigmatism, but significantly more complications compared to ECCE. Strength of Recommendation: Weak. Level of Evidence: Low– Moderate.
REFERENCES
1. Gogate PM, Deshpande M, Wormald RP, et al. Extracapsular cataract surgery compared with manual small incision cataract surgery in community eye care setting in Western India: a randomised controlled trial. Br J Ophthalmol 2003;87:667- 72.
2. Gurung A, Karki DB, Shrestha S, Rijal AP. Visual outcome of conventional extracapsular cataract extraction with posterior chamber intraocular lens implantation versus manual small-incision cataract surgery. Nepal J Ophthalmol 2009;1:13-9.
3. George R, Rupauliha P, Sripriya AV, et al. Comparison of endothelial cell loss and surgically induced astigmatism following conventional extracapsular cataract surgery, manual small-incision surgery and phacoemulsification. Ophthalmic Epidemiol 2005;12:293-7.
4. Ang M, Evans JR, Mehta JS. Manual small incision cataract surgery (MSICS) with posterior chamber intraocular lens versus extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens for age-related cataract. Cochrane Database Syst Rev 2014;11 :CD008811 .
APPENDIX Q3
SUMMARY OF EVIDENCE
There was no significant difference between FLACS and conventional phacoemulsification in the overall result, in terms of improvement in vision, measured by uncorrected distance visual acuity.1,2 It was also insignificant when sub-grouped by follow-up time (at 1 week, 1 month and 6 months).
As for improvement in vision (measured by corrected distance visual acuity), there was a significant difference favoring FLACS when looking at the overall result, with a mean difference of -0.03 LogMAR units.* (Please refer to Appendix Q4 for the Snellen equivalent). This implies a significant improvement of visual acuity by 0.03 using the LogMAR chart favoring FLACS. The difference is also significant at 1 week and at 6 months postoperatively.1-3
However, among the adverse outcomes, the differences were insignificant between FLACS and conventional phacoemulsification in the rates of anterior capsule tear,4,5 elevated intraocular pressure,4,6 and macular edema.4,6
One study showed that based on the simulated complication rates of phacoemulsification and FLACS and assuming resultant visual acuity outcome improvement of 5% in uncomplicated cases of FLACS, the cost-effectiveness (dollars spent per QALY) gained from FLACS was not cost-effective at AUD $92,862.7
There were 7 RCTs1- 7 and 1 meta-analysis2 that showed these findings. Unfortunately there was unclear to high risk for bias for the included studies. These were mainly from issues with randomization and allocation concealment. The studies were also at high risk for performance and detection bias. Consistency issues were seen in the primary outcomes, but not evident in the complications.
DRAFT RECOMMENDATION
Among patients with senile cataracts, FLACS is better over conventional phacoemulsification, in terms of corrected distance visual acuity. Level of Evidence: Very Low. Strength of Recommendation: Weak.
1. Kránitz K, Miháltz K, Sándor GL, et al. Intraocular lens tilt and decentration measured by Scheimpflug camera following manual or femtosecond laser-created continuous circular capsulotomy. J Refract Surg 2012;28:259-263.
2. Mastropasqua L, Toto L, Mattei PA, et al. Optical coherence tomography and 3-dimensional confocal structured imaging system-guided femtosecond laser capsulotomy versus manual continuous curvilinear capsulorhexis. J Cataract Refract Surg. 2014;40:2035-2043.
3. Filkorn T, Kovács I, Takács A, et al. Comparison of IOL power calculation and refractive outcome after laser refractive cataract surgery with a femtosecond laser versus conventional phacoemulsification. J Refract Surg 2012;28:540-544.
4. Conrad-Hengerer I, Al Juburi M, Schultz, T., et al. Corneal endothelial cell loss and corneal thicknessin conventional compared with femtosecond laser-assisted cataract surgery: three-month follow-up. J Cataract Refract Surg 2013;39:1307- 1313.
5. Reddy KP, Kandulla J, Auffarth GU. Effectiveness and safety of femtosecond laser-assisted lens fragmentation and anterior capsulotomy versus the manual technique in cataract surgery. J Cataract Refract Surg 2013;39:1297-1306.
6. Conrad-Hengerer I, Hengerer FH, Al Juburi M, et al. Femtosecond laser-induced macular changes and anterior segment inflammation in cataract surgery. J Refract Surg 2014;30:222-226.
7. Abell RG, Vote BJ. Cost-effectiveness of femtosecond laser-assisted cataract surgery versus phacoemulsification cataract surgery. Ophthalmology. 2014;121:10-1 6.
8. Chen X, Xiao W, Ye S, et al. Efficacy and safety of femtosecond laser-assisted cataract surgery versus conventional phaco-emulsification for cataract: a meta-analysis of randomized controlled trials. Sci Rep 2015;5:13123.
Q5. AMONG PATIENTS WITH SENILE CATARACTS SCHEDULED FOR SURGERY, WILL ROUTINE MEDICAL PRE-OPERATIVE TESTING VERSUS NO ROUTINE TESTING REDUCE MORTALITY, MORBIDITY, AND ADVERSE EVENTS?
SUMMARY OF EVIDENCE
Based on moderate level of evidence, there was no significant difference in the rates of intraoperative or postoperative ocular and medical adverse events between routine medical preoperative testing and no routine medical preoperative testing.
A meta-analysis of 3 randomized controlled trials that included 21,531 cataract surgeries done under local anesthesia showed that overall risk for adverse medical events from cataract surgery was low edema(3 out of 100 surgeries).1 The rate of adverse events was similar between the routine preoperative testing group (353 events out of 10,764 surgeries) and the no routine testing group (354 events out of 10,766 surgeries). Adverse events were mostly cardiovascular in nature (e.g. half were blood pressure elevations requiring treatment) and occurred intraoperatively. The rate of postponement or cancellation of surgery was also similar in the 2 groups (161 out of 10,287 surgeries in the routine testing group vs. 166 out of 10,295 surgeries in the no testing group).2,3 Cost was evaluated in one study, which estimated that the cost was 2.5 times higher in those who underwent preoperative testing than those who did not.2
Only one study reported rates of myocardial infarction, stroke, and hypoglycemia within 7 days of cataract surgery separately.3 There was no difference between routine testing and no testing for these outcomes, however confidence intervals for the results were wide, because event rates were very low (less than 10 in 10,000 in both groups). None of these events occurred intraoperatively.
Majority of the participants enrolled in the included studies were patients with mild to severe, non-incapacitating systemic diseases (e.g. hypertension, diabetes, congestive heart failure, and bleeding disorders). Routine preoperative tests included ECG, CBC, blood sugar, serum electrolytes, BUN and creatinine. Outcomes evaluated were ocular complications, medical adverse events requiring treatment, and postponement or cancellation of surgery.
The results of the meta-analysis were driven mainly by the largest study in the meta-analysis, which included a total of more than 19,000 surgeries3. However, this trial was methodologically sound, and the results were consistent across all the studies included in the meta-analysis.
Given these findings, routine medical pre- operative testing is not recommended for patients with senile cataracts scheduled for surgery.
DRAFT RECOMMENDATION
Among patients with senile cataracts scheduled for cataract surgery under local anesthesia, routine medical pre-operative testing is NOT recommended. Level of Evidence: Moderate-high Strength of Recommendation: Strong.
REFERENCES
1. Keay L, Lindsley K, Tielsch J, et al. Routine preoperative medical testing for cataract surgery. Cochrane Database Syst Rev 2012;3:CD007293.
2. Lira RP, Nascimento MA, Moreira-Filho DC, et al. Are routine preoperative medical tests needed with cataract surgery? Rev Panam Salud Publica. 2001;10:13-7.
3. Schein OD, Katz J, Bass EB, et al. The value of routine preoperative medical testing before cataract surgery. Study of medical testing for cataract surgery. N Engl J Med 2000; 342:168-175.
4. Cavallini GM, Saccarola P, D’Amico R, et al. Impact of preoperative testing on ophthalmologic and systemic outcomes in cataract surgery. Eur J Ophthalmol 2004;14:369- 74.
SUMMARY OF EVIDENCE
There is no randomized trial found in the literature search to answer the research question. Instead, a prospective cohort study is available where 282 (40%) patients who received no lacrimal system irrigation nor topical antibiotic prior to surgery was compared to 418 (60%) patients who received lacrimal system irrigation with or without neomycin eye drops.1 No patient developed postoperative endophthalmitis in both groups. Although the overall bacterial contamination was reported at 14.1%, the actual number of patients per group was not mentioned.
DRAFT RECOMMENDATION
There is still inadequate evidence for or against recommending routine lacrimal duct irrigation. Level of Evidence: Very Low. Strength of Recommendation: Weak.
REFERENCE
1. Mistlberger A, Ruckhofer J, Raithel E, et al. Anterior chamber contamination during cataract surgery with intraocular lens implantation. J Cataract Refract Surg 1997;23:1064-9.
SUMMARY OF EVIDENCE
Based on a low-quality cohort study, the risk of infection in delayed sequential bilateral cataract surgery (DSBCS) with intracameral prophylactic antibiotics is very small (1 in 29,582). A non-significant 2 fold increase in the risk of infection was observed among immediate sequential bilateral cataract surgery (ISBCS) patients who were given prophylactic intracameral antibiotics.1
The subjective improvement in visual function is not significantly different in ISCBS and DSCBS patients based on a meta-analysis2 of 2 randomized studies.3,4 The two trials had conflicting results for this outcome and were significantly very dissimilar. There is also no statistically significant difference in the risk of any intra- and post-operative complications (capsule tears, vitreous loss, iridectomy, sphincterotomy, sutures in wound, intraocular pressure >30 mmHg, wound leak IOL decentration or deplacement, anterior chamber flare, capsular fibrosis, capsule opacification, foreign body sensation, dry eyes and more serious complications such as corneal edema, macular edema, wound leak, or iris prolapse) between patients who underwent ISCBS and DSCBS.3,4 Likewise, there is no statistically significant difference in the risk of serious post-operative complications (corneal edema, macular edema, wound leak, or iris prolapse) between the aforementioned groups.
Canadian estimates of crude cost savings from ISCBS over DSCBS is pegged at US$1,606 (valued in 2013) per patient with adjusted estimates pegged at US$1,431 per quality-adjusted life-year gained.5 Converting these based on 2013 average peso- dollar exchange rate, crude cost savings amount to Php 68,202 per patient while adjusted cost savings is Php 60,746 per QALY gained. Considering the number of patients needing cataract surgery, the cost savings can potentially add up even if we consider cost variation in different countries. In the Philippines, it is also important to consider the opportunity cost for the caregiver or watcher (bantay ) of the patient. Often, patients will come for consultations and procedures with a handful of bantays. The collective lost earnings of these people are substantial and may confer additional cost savings in favor of ISCBS.
Aside from benefits in terms of costs, ISCBS confers additional benefits to patients: rapid visual recovery and functional advantage in the short term. ISCBS patients tend to regain visual functions earlier than their DSCBS counterparts. Unfortunately, among patients who underwent ISCBS, the very short interval between the surgeries of the two eyes precludes adjustments in surgical plans based on the result of the first eye surgery.6
DRAFT RECOMMENDATION
The technique of immediate sequential bilateral cataract surgery (also called same sitting bilateral cataract surgery) cannot be routinely offered to patients at this time. Despite the significant cost savings, the attendant risk for serious bilateral eye complications cannot be discounted with confidence. Level of Evidence: Very Low to Low. Strength of Recommendation: Weak.
1. Arshinoff SA, Bastianelli PA. Incidence of postoperative endophthalmitis after immediate sequential bilateral cataract surgery. J Cataract Refract Surg 2011;37:2105-2114.
2. Kessel L, Andresen J, Erngaard D, et al. Immediate sequential bilateral cataract surgery: a systematic review and meta-analysis. J Ophthalmology. 2015;912481.
3. Serrano-Aguilar P, Ramallo-Fariña Y, Cabrera-Herńandez JM, et al.. Immediately sequential versus delayed sequential bilateral cataract surgery: safety and effectiveness. J Cataract Refract Surg. 2012;38:1734-1742.
4. Sarikkola AU, Uusitalo RJ, Hellstedt T, et al. Simultaneous bilateral versus sequential bilateral cataract surgery: Helsinki simultaneous bilateral cataract surgery study report 1. J Cataract Refract Surg. 2011;37:992-1002.
5. Malvankar-Mehta MS, Filek R, Iqbal M, et al. Immediately sequential bilateral cataract surgery: a cost-effective procedure. Can J Ophthalmol. 2013;48:482-488.
6. American Academy of Ophthalmology Cataract and Anterior Segment Panel. Preferred Practice Pattern Guidelines. Cataract in the Adult Eye. San Francisco CA: American Academy of Ophthalmology; 2011 . (Accessed at www.aao.org/ppp on June 20, 2016).
SUMMARY OF EVIDENCE
There were 3 randomized controlled trials (RCTs) found in the literature search to answer the research question but investigated different kinds of antibiotics. One RCT compared topical regimen (chloramphenicol-sulphadimidine ointment) plus periocular penicillin at the time of surgery with topical regimen alone.1 This study done in northern Pakistan found significant reduction of endophthalmitis with topical regimen plus periocular penicillin (RR 0.33, 95% CI 0.12–0.92) during surgery compared with topical regimen alone. In another RCT conducted in Turkey, balanced salt solution (BSS) irrigation with vancomycin and gentamycin was compared to BSS alone showed no benefit from vancomycin and gentamycin (RR 0.20, 95% CI 0.01–4.15).2 The last RCT of high quality evidence was based on a 2 x 2 factorial design, with intracameral cefuroxime and topical perioperative levofloxacin resulting in 4 treatment groups.3 This was conducted by the European Society of Cataract & Refractive Surgeons (ESCRS) involving 16,603 eyes of 16,603 patients from multiple sites in Europe and Turkey. The results of this study showed that intracameral cefuroxime alone (RR 0.20, 95% CI 0.04–0.91) and combined intracameral cefuroxime with topical levofloxacin (RR 0.10, 95% CI 0.27–0.78) showed significant reduction in endophthalmitis as compared to no antibiotic prophylaxis. However, the reduction of endophthalmitis with topical levofloxacin alone as compared to no antibiotics was not statistically significant (RR 0.70, 95% CI 0.27–1.84). Other comparisons such as intracameral cefuroxime vs topical levofloxacin, combined intracameral cefuroxime and topical levofloxacin vs intracameral cefuroxime, intracameral cefuroxime and topical levofloxacin vs topical levofloxacin did not result in significant reduction in endophthalmitis. There was also no statistically significant reduction in the final visual acuity following endophthalmitis among patients given intracameral cefuroxime with/without topical levofloxacin as compared to no intracameral cefuroxime with/without topical levofloxacin.
Despite this reduction in endophthalmitis, a number of case reports and case series have been published on harm of intracameral and intravitreal cefuroxime. Anterior and posterior segment inflammation were reported in six patients with high doses of intracameral cefuroxime.4 All six patients in this series had satisfactory final visual outcome even without surgical intervention. Inadvertent overdose of cefuroxime caused hemorrhagic retinal infarction in four patients5 and macular infarction and associated cystoids macular edema.6 Two patients developed anaphylactic reactions from intracameral7 and intravitreal8 cefuroxime.
DRAFT RECOMMENDATION
Intracameral cefuroxime with or without topical levofloxacin may be recommended for prophylaxis against endophthalmitis (Level of Evidence: High), although there is possibility of serious adverse events. (Level of Evidence: Very Low). Strength of recommendation: Weak. Topical regimen (chloramphenicol-sulphadimidine ointment) plus periocular penicillin may also be recommended over topical regimen alone. Level of Evidence: Moderate. Strength of Recommendation: Strong.
REFERENCES
1. Christy NE, Sommer A. Antibiotic prophylaxis of post-operative endophthalmitis. Ann Ophthalmol. 1979;11 :1261- 5.
2. Sobaci G, Tuncer K, Taş A, et al. The effect of intraoperative antibiotics in irrigating solutions on aqueous humor contamination and endophthalmitis after phacoemulsification surgery. Eur J Ophthalmol. 2003;13:773-8.
3. Endophthalmitis Study Group, European Society of Cataract & Refractive Surgeons. Prophylaxis of postoperative endophthalmitis following cataract surgery: results of the ESCRS multicenter study and identification of risk factors. J Cataract Refract Surg. 2007;33:978-88.
4. Delyfer MN, Rougier MB, Leoni S, et al. Ocular toxicity after intracameral injection of very high doses of cefuroxime during cataract surgery. J Cataract Refract Surg. 2011;37:271- 8.
5. Çiftçi S, Çiftçi L, Dağ U. Hemorrhagic retinal infarction due to inadvertent overdose of cefuroxime in cases of complicated cataract surgery: retrospective case series. Am J Ophthalmol. 2014;157:421- 425.
6. Qureshi F, Clark D. Macular infarction after inadvertent intracameral cefuroxime. J Cataract Refract Surg. 2011;37:1168-9.
7. Moisseiev E, Levinger E. Anaphylactic reaction following intracameral cefuroxime injection during cataract surgery. J Cataract Refract Surg. 2013;39:1432-4.
8. Villada JR, Vicente U, Javaloy J, Alió JL. Severe anaphylactic reaction after intracameral antibiotic administration during cataract surgery. J Cataract Refract Surg. 2005;31:620-1.
SUMMARY OF EVIDENCE
There is one randomized controlled trial (RCT) and one prospective cohort study found in the literature search to answer the research question. The RCT however does not specify the concentration of Povidone-Iodine (PI) solution used.1 A total of 4,111 eyes underwent cataract surgery and were included in this study. There was no significant difference between the PI group and the control (silver protein) group (RR 1.17, 95% CI 0.57 – 2.42). The prospective cohort study including 8,083 eyes showed significant difference between 5% PI and no 5% PI (p <0.03).2 However, on rechecking, it turned out that this is not significant (RR 0.24, 95% CI0.57 – 1.08). Pooled analysis of these two studies (PI vs control) showed a trend of benefit toward PI with an RR of 0.61 (95% CI 0.13 – 2.86, I2 72%). These two studies are both low quality.
In several case reports, conjunctival irritation is seen in 0.4%.3 Contact dermatitis is less common (0.04%); however, the risk increases tenfold in the presence of allergy to shellfish or iodine.4 Despite the increased risk for allergy, patients are still recommended to receive PI prior to surgery.5 Keratoconjunctivitis sicca has also been reported.5 Hyperemia of conjunctiva, superficial punctate epitheliopathy and epithelial defect, corneal symptoms (edema or Descemet’s membrane folds, and mild to moderate Tyndall were seen in randomized trial comparing different concentrations of PI solutions
DRAFT RECOMMENDATION
Routine pre-operative 5% PI solution is not recommended because of lack of evidence of effectiveness but also the possibility of adverse events. Level of Evidence: Low-Very Low. Strength of Recommendation: Weak.
REFERENCES:
1. Mørk P. Polyvinylpyrrolidone-iodine as a disinfectant in eye surgery for five years. Acta Ophthalmol (Copenh). 1987;65:572-4.
2. Speaker MG, Menikoff JA. Prophylaxis of endophthalmitis with topical povidone-iodine. Ophthalmology. 1991;98:1769-75.
3. Zamora JL. Chemical and microbiologic characteristics and toxicity of povidone-iodine solutions. Am J Surg. 1986;151:400-6.
4. Li B, Nentwich MM, Hoffmann LE, et al. Comparison of the efficacy of povidone-iodine 1.0%, 5.0%, and 10.0% irrigation combined with topical levofloxacin 0.3% as preoperative prophylaxis in cataract surgery. J Cataract Refract Surg. 2013;39:994-1001.
5. Gills JP. Effective concentration of betadine. J Cataract Refract Surg. 1999;25:604.
SUMMARY OF EVIDENCE
Three studies were identified addressing the adverse effects of Nd:YAG laser capsulotomy in patients with PCO but none of these studies compared the less than 6 months versus 6 months and beyond timing of the capsulotomy. One study however compared different time durations from 6 months up to greater or equal to 37 months3. The sample sizes were 231, 312 and 3143 adult patients, with follow-up observations ranging from as early as immediately after the procedure to three months post-capsulotomy.
From the very low quality evidence from the two studies with small sample sizes, the limited available data does not seem to show any statistically significant differences (p <0.05) between the anterior chamber depth, intraocular pressure, macular foveal thickness and endothelial cell loss before and after the capsulotomy.
However, the cohort study by Shaikh et al.3 in 2010 demonstrates that laser capsulotomy may induce potential complications, prevalence rates of which are summarized below in this table:
DRAFT RECOMMENDATION
There is no evidence to recommend performing Nd:YAG laser capsulotomy less than 6 months versus 6 months and beyond after the cataract surgery for those who develop PCO. Evidence only shows that Nd:YAG laser capsulotomy performed at least 6 months from cataract surgery may lead to potential complications. Level of Evidence: Very Low. Strength of Recommendation: Weak.
REFERENCES
1. Ozkurt YB, Sengör T, Evciman T, Haboğlu M. Refraction, intraocular pressure and anterior chamber depth changes after Nd:YAG laser treatment for posterior capsular opacification in pseudophakic eyes. Clin Exp Optom 2009;92:412-415.
2. Ruiz-Casas D, Barrancos C., Alio JL, et al. Effect of posterior Neodymium:YAG capsulotomy. Safety evaluation of macular foveal thickness, intraocular pressure and endothelial cell loss in pseudophakic patients with posterior capsule opacification. Arch Soc Esp Oftalmol 2013; 88:415-422.
3. Shaikh A, Shaikh F, Adwani JR, Shaikh ZA. Prevalence of different Nd:YAG laser induced complication in patients with significant posterior capsule opacification and their correlation with time duration after standard cataract surgery. Int J Med & Med Sci. 2010;2:012-017.
After three rounds of discussions and voting during the CPG panel conference, there was one issue that could not be resolved, that is, the majority consensus of 70% could not be reached. The issue was whether to recommend ECCE over MSICS or MSICS over ECCE. The matter was then shelved and slated for resolution via the Delphi technique through e-mail.
The panelists were reminded that they would receive email and be expected respond promptly to continue the discussion on ECCE and MSICS in the following weeks. Voting would be conducted also by email for three successive rounds again or until a consensus is reached. No new evidence would be presented but the panelists were allowed more time to ponder on the evidence and the panel discussion.
The first round yielded the results illustrated in Figure 1 with comments in Table 1.
