Retinal thickness changes after phacoemulsification

Narrative review after post-hoc trial analysis of factors that predict corneal endothelial cell loss after phacoemulsification: Tips for improving cataract surgery research

PURPOSE

Identifying pre/perioperative factors that predict corneal endothelial-cell loss (ECL) after phacoemulsification may reveal ways to reduce ECL. Our literature analysis showed that 37 studies have investigated one or several such factors but all have significant limitations. Therefore, the data of a large randomized controlled trial (PERCEPOLIS) were subjected to post-hoc multivariate analysis determining the ability of nine pre/perioperative variables to predict ECL.

METHODS

PERCEPOLIS was conducted in 2015-2016 to compare two phacoemulsification techniques (subluxation and divide-and-conquer) in terms of 3-month ECL. Non-inferiority between the techniques was found. In the present study, post-hoc univariate and multivariate analyses were conducted to determine associations between ECL and age, sex, cataract density, preoperative endothelial-cell density, phacoemulsification technique, effective phaco time (EPT), and 2-hour central-corneal thickness. The data are presented in the context of a narrative review of the literature.

RESULTS

Three-month data were available for 275 patients (94% of the randomized cohort; mean age, 74 years; 58% women). Mean LOCSIII cataract grade was 3.2. Mean EPT was 6 seconds. Mean ECL was 13%. Only an older age (beta = 0.2%, p = 0.049) and higher EPT (beta = 1.2%, p = 0.0002) predicted 3-month ECL. Cataract density was significant on univariate (p = 0.04) but not multivariate analysis. The other variables did not associate with ECL.

CONCLUSIONS

Older age may amplify ECL due to increased endothelial cell fragility. EPT may promote ECL via cataract density-dependent and -independent mechanisms that should be considered in future phacoemulsification research aiming to reduce ECL. Our literature analysis showed that the average ECL for relatively unselected consecutively-sampled cohorts is 12%.

Early Macular Thickness Changes after Trabeculectomy and Combined Phaco-Trabeculectomy

Purpose

To assess postoperative changes in central retinal thickness (RT) following trabeculectomy and combined phaco-trabeculectomy using spectral domain-optical coherence tomography.

Methods

In a prospective interventional comparative study, 64 consecutive glaucoma patients who underwent trabeculectomy (32 eyes) or phaco-trabeculectomy (32 eyes) were included. A macular thickness map using the Early Treatment Diabetic Retinopathy Study circles of 1 mm, 3 mm, and 6 mm was the standard to evaluate the 9-subfield thickness preoperatively and again at 1 and 3 months after surgery. Four subfields in each of the 3 mm and 6 mm rings were considered parafoveal and perifoveal regions, respectively.

Results

Preoperative measurements were similar in the two groups, except patients in the combined group which were older (P = 0.002). The mean RT in the combined phaco-trabeculectomy group at month 1 was significantly higher than baseline measurements at central subfield retinal thickness (CSRT) (P = 0.01), temporal (P = 0.001), and inferior (P = 0.04) parafoveal and temporal (P = 0.01), superior (P = 0.02), and nasal (P < 0.001) perifoveal quadrants; however, RT changes in the trabeculectomy-only group were not statistically significant at months 1 and 3 (P > 0.05). The increase in the temporal perifoveal RT of the combined phaco-trabeculectomy group persisted at month 3 (P = 0.01), while the RT in other sectors returned to preoperative values. The two treatment groups did not differ in terms of changes in the CSRT over time (P = 0.37). In addition, no difference was observed between the treatment groups regarding the parafoveal RTs at each time points (0.06 ≤ P ≤ 0.29).

Conclusions

There was no significant difference in the pattern of changes of CSRT and parafoveal RT between trabeculectomy and combined phaco-trabeculectomy treatment groups up to 3 months after surgery. Some detectable increase in RT in the combined phaco-trabeculectomy will reverse to baseline values 3 months after surgery, except in the temporal perifoveal region.

Spontaneous closure of a chronic full-thickness idiopathic macular hole after Irvine-Gass syndrome resolution

Background

Full-thickness idiopathic macular hole (IMH) usually causes serious visual deformities and visual acuity loss. Pseudophakic cystic macular edema, also known as Irvine-Gass syndrome, is another entity that causes visual disturbances, and occurs mainly after cataract extraction. We present a case report of a patient that was diagnosed with a full-thickness macular hole that spontaneously closed after the resolution of an Irvine-Gass syndrome, which occurred after an uneventful cataract extraction.

Case presentation

A 75 years-old female presented with the complaints of decreased visual acuity and color contrast sensitivity on both eyes (OU) and central visual field deformations on her left eye (LE). She was diagnosed with a full-thickness IMH on her LE, and cataract on OU. After an uneventful cataract extraction via phacoemulsification, she developed an Irvine-Gass syndrome at her LE, which was treated topically. The IMH closed spontaneously after the resolution of the Irvine-Gass syndrome, and the patient is being followed with no further complaints.

Conclusion

The exact mechanism for spontaneous closure of full-thickness idiopathic macular holes is still not completely understood. In this case, we hypothesize that the coalesced intraretinal cysts caused by the Irvine-Gass syndrome formed a bridge-like structure connecting the inner walls of the macular hole, thus connecting the remnants of the Muller cells which enabled the full recovery of the normal foveal structure.

Short-Term Outcomes of Cataract Surgery in Patients with a History of Central Serous Chorioretinopathy

Purpose

This study aimed to evaluate the short-term outcomes of cataract surgery in patients with a history of idiopathic central serous chorioretinopathy (CSC).

Methods

This retrospective study included 26 patients with a history of CSC who underwent uncomplicated phacoemulsification and intraocular lens implantation. The best-corrected visual acuity (BCVA) and central foveal thickness (CFT) measured before the surgery were compared with those obtained at mean 3.6 months after the surgery. BCVA outcome was also analyzed in eyes with and without subretinal fluid (SRF).

Results

The mean logarithm of the minimal angle of resolution BCVA significantly improved from 0.52 ± 0.40 before the surgery to 0.21 ± 0.30 one month after the surgery and 0.20 ± 0.31 at 3.6 months after the surgery (P < 0.001). The mean CFT was 281.2 ± 84.2 μm before the surgery, 301.5 ± 90.7 μm one month after the surgery, and 279.9 ± 83.6 μm at 3.6 months after the surgery. The CFT before surgery was not different from those measured at 3 months (P=0.253). Significant improvement in BCVA at 3.6 months was noted in the SRF group (N = 12, P=0.003) and the non-SRF group (N = 14, P=0.001). CSC recurrence was noted in 2 patients in the non-SRF group.

Conclusions

Significant improvement in visual acuity was noted after cataract surgery in patients with a history of idiopathic CSC, without a risk of aggravation of CSC in most patients.

Therapeutic Efficacy of Difluprednate 0.05% Versus Prednisolone Acetate 1% in Controlling Inflammation and Macular Oedema Following Phacoemulsification: An Optical Coherence Tomography-Based Study

BACKGROUND

Topical corticosteroids have been the cornerstone in the management of postoperative inflammation following cataract surgery. Due to potential side effects of the older topical steroids like prednisolone acetate and dexamethasone or betamethasone, newer potent steroids preparation like difluprednate, loteprednol or fluorometholone are now being used at lesser dose and frequency to control inflammation. There is scanty literature on the efficacy of these drugs in preventing inflammation and macular oedema in the Indian population.

PURPOSE

The purpose of this study was to compare the efficacy of difluprednate 0.05% against prednisolone 1% eye drops for control of inflammation following phacoemulsification. The adverse effects of both drugs were also evaluated in this retrospective study.

METHODS

This retrospective cohort study included 181 patients operated for age-related cataracts by a single surgeon at a tertiary referral eye hospital between December 2018 and March 2019. Patients received either difluprednate 0.05% emulsion (n=90 eyes) or prednisolone acetate 1% (n=91 eyes) after phacoemulsification with the same brand intraocular lens (IOL) and same phaco machine. The topical medication was initiated one day postoperatively and continued for six weeks in tapering dosage. Pain score (Visual Analogue Scale, VAS), conjunctival hyperemia, anterior chamber (AC) cell grading, corneal oedema, central retinal thickness, subclinical cystoid macular oedema (SCME), intraocular pressures (IOP) and best-corrected visual acuity (BCVA) were examined after one week and six weeks of cataract extraction.  Results: There was no statistically significant difference observed with regards to pain score (no pain in any patients after six weeks), conjunctival hyperemia (no hyperemia in any patients after six weeks), AC inflammation (no reaction in any patients), central retinal thickness (234.44 ± 35.75µ vs. 234.8 ± 34.99µ, p-value 0.946), SCME (16.67% vs. 13.19%, p-value 0.511), IOP (16.8 vs. 15.47 mmHg, p-value 0.101) and BCVA (BCVA 6/6 in 57.7% vs. 70.32%, p-value >0.05) between both groups. The mean change in IOP in both the groups at one week (0 ± 4.4 vs. 1.87 ± 3.54, p-value 0.0007) and six weeks (-0.01 ± 5.53 vs. 1.88 ± 4.01, p-value 0.004) was significant.  Conclusion: Both the groups were equivalent with regards to their therapeutic efficacy in controlling postoperative inflammation and restoration of vision following phacoemulsification.

Effect of infusion pressure during cataract surgery on ganglion cells measured using isolated-check visual evoked potential

AIM

To detect the relationship between infusion pressure and postoperative ganglion cells function.

METHODS

This prospective observational cohort study included sixty-one eyes that underwent uncomplicated cataract surgery. Patients were divided into two groups according to infusion time (IT) recorded using surgery equipment [Group A: IT>IT_mean (27 eyes); Group B: IT<IT_mean (34 eyes)]. Best-corrected visual acuity, isolated-check visual evoked potential (icVEP), microperimetry, and optical coherence tomography examinations were performed preoperatively and 1wk and 1mo postoperatively. The changes in test results were measured with independent-sample t-tests and paired t-tests. Correlation between IT and these changes were analyzed with Pearson's correlation analysis and Spearman correlation analysis.

RESULTS

Neither group showed significant postoperative changes in macular ganglion cell-inner plexiform layer (mGC-IPL) thickness (1-week postoperative: Group A P=0.185, Group B P=0.381; 1-month postoperative: Group A P=0.775, Group B P=0.652). Postoperative mGC-IPL thickness of Group A was not significantly thicker than that of Group B at both post surgery time point (1-week postoperative P=0.913; 1-month postoperative P=0.954). In Group A, the mGC-IPL thickness change 1wk postoperatively was positively correlated with IT (R²=0.156, P=0.0198). A suspected progressive deficit in the magnocellular pathway was also found in Group A 1-month postoperatively [individual observed F (IOF)=0.63±0.70]. Significant increases were observed in postoperative retinal sensitivity measured by microperimetry (1-week postoperative: Group A P=0.015, Group B P<0.001; 1-month postoperative: Group A P=0.005, Group B P<0.001). In Group B, IT was negatively correlated with the increase in macular sensitivity (1-week postoperative: R²=0.372, P<0.001; 1-month postoperative: R²=0.209, P=0.007).

CONCLUSION

Both mGC-IPL thickness and retinal sensitivity increased postoperatively. A suspected progressive deficit in the magnocellular pathway was found in the group with a long IT, which induced more prominent changes.

Changes in peripapillary retinal nerve fiber layer thickness in chronic glaucoma and non-glaucoma patients after phacoemulsification cataract surgery

Background: Phacoemulsification is a common cataract operation nowadays. During phacoemulsification, variation in intraocular pressure (IOP) may occur, which might change the retinal nerve fiber layer (RNFL) thickness. This study was aimed to evaluate the change in peripapillary RNFL thickness and mean deviation (MD) of visual field after phacoemulsification in chronic primary glaucoma and non-glaucoma patients. Methods: Cohort prospective study was done on 26 patients (13 chronic glaucoma eyes and 13 non-glaucoma eyes) who underwent phacoemulsification. The changes in peripapillary RNFL thickness and MD of visual field were measured as the primary outcome. Comparison between pre- and post-surgery was analyzed with paired t-test, while unpaired t-test was used for comparison between groups.Results: There were no significant changes in RNFL thickness on both groups. Average RNFL thickness in glaucoma group before and after phacoemulsification were 94.9±20.0 μm and 99.1±21.3 μm, respectively (p>0.05). Average RNFL thickness in non-glaucoma group were 100.2±11.1 μm and 101.7±6.8 μm, respectively (p>0.05). Glaucoma patients yielded decreasing mean deviation (MD) of visual field, but it was not statistically significant (p=0.071). In contrast, the MD of visual field after surgery was significantly increased in non-glaucoma group (p=0.005).Conclusion: Phacoemulsification tended to increase peripapillary RNFL thickness in glaucoma or non-glaucoma patients. The visual field tended to decrease in glaucoma patients, but was significantly increased in non-glaucoma patients.