Approaching cataract surgery in patients with fuchs' endothelial dystrophy

Nanopore sequencing method for CTG18.1 expansion in TCF4 in late-onset Fuchs endothelial corneal dystrophy and a comparison of the structural features of cornea with first-degree relatives

BACKGROUND

To evaluate the relationship between the number of trinucleotide repeats (TNR) in late-onset Fuchs corneal endothelial dystrophy (FCED) and to compare the endothelial properties of FCED, first-degree relatives, and controls.

METHODS

Blood samples were collected from FCEDs to determine TNR number. The FCED patients, first-degree relatives, and controls were examined with specular microscopy for central corneal thickness (CCT), endothelial cell density (ECD), pleomorphism and polymegatism, and with corneal topography for specific indicators such as (i) displacement of thinnest point of cornea, (ii) loss of isopachs, (iii) focal posterior surface depression towards anterior chamber.

RESULTS

This study included 92 patients with FCED, 92 first-degree relatives, and 96 controls. CCT was thickest in FCEDs (558.0 μm) (p < 0.05) while there was no difference between relatives (533.0 μm) and controls (530.4 μm) (p = 0.845). ECD was decreased in both FCED (2069.2 mm2) and relatives (2171.4 mm2) than controls (2822.9 mm2) (p < 0.05 in both). The presence of pleomorphism and polymegatism was significant in patients with FCED (93.4% and 93.4%, respectively), relatives (86.9% and 86.04%, respectively), and controls (8.33% and 1.04%, respectively) (p < 0.05). Specific topographic indicators differed among the groups (p < 0.05). The mean repeat number of the FCED patients was 17.48 ± 4.54 (12-25) times. The TNR number of FCED cases correlated with the relative CCT (p < 0.05, R = 0.615) and cell density (p = 0.009, R = -0.499).

CONCLUSIONS

A strong association between the corneal endothelium in relatives and TNR number of FCEDs was defined. Relatives tended to have fewer corneal endothelial cells, even though they did not have clinical findings.

The outcomes of postoperative eye patching after cataract surgery in patients with Fuchs' endothelial corneal dystrophy

PURPOSE

To investigate the influence of post-operative eye patching on corneal thickness, endothelial cells' loss and visual acuity in patients diagnosed Fuchs' endothelial corneal dystrophy (FECD).

SETTING

Public healthcare centre, Shamir Medical Centre, Israel.

METHODS

This randomized controlled trial included patients with FECD undergoing routine cataract surgery in a public medical centre. Patients were randomly assigned to 2 groups: the eye undergoing surgery was covered with a patch for 24 h in the first group (patched group), and a plastic shield was used in the second (non-patched group). Both groups received a unique dose of a local steroid and antibiotic post-operatively. The eyes were examined pre-operatively, and on days 1, 7 and 30 post-surgery . Examination included: best corrected visual acuity (BCVA), comeplete slit lamp examination, intra ocular pressure (IOP), anterior chamber depth (ACD), central corneal thickness (CCT) using the IOL Master 700 (Zeiss, Germany) and endothelial cell density (ECD) using Specular microscopy. Cumulative dissipated energy (CDE) and operation time were recorded for all cases.

RESULTS

The study included 46 eyes of 46 patients diagnosed with FECD. Twenty-three eyes in the patched group, and 23 eyes in the non-patched group . Thirty days post-operatively the CCT in the patched group decreased by 60 ± 38 mµ (9%) compared to 92 ± 80 mµ (13.5%) in the non- patched group (p = 0.04). Seven days post-operatively the CCT in the patched group decreased by 31 ± 35 mµ (5%) compared to 58 ± 76 (8%) in the non-patched group, but this difference did not reach statistical significance (p = 0.081). There was no statistically significant difference in endothelial cells loss as well as BCVA at 1, 7 and 30 days post-operatively between the study groups.

CONCLUSIONS

Avoiding eye patch post-operatively after cataract surgery in patients with FECD results in better corneal clarity recovery and reduced corneal edema one month post-operatively. Visual acuity and endothelial cell's loss were not influenced by patching.

Effect of Simultaneous Endothelial Keratoplasty and Cataract Surgery: A Secondary Analysis of the Descemet Endothelial Thickness Comparison Trial

PURPOSE

Combining cataract surgery with endothelial keratoplasty (triple EK) is a common practice and may be safer because it commits the patient to only one surgery. This study aimed to determine whether outcomes of pseudophakic endothelial keratoplasty and triple EK have similar outcomes.

METHODS

This was a non-prespecified secondary analysis of a multicenter, double-masked, randomized, controlled clinical trial. Enrollment centers included the Casey Eye Institute at Oregon Health and Sciences University and the Byers Eye Institute at Stanford University. Patients with damaged or diseased endothelium and were considered good candidates for either Descemet membrane endothelial keratoplasty or ultrathin Descemet stripping automated endothelial keratoplasty were randomized to one of the two surgeries 1-2 days prior to surgery. If the patient had a cataract, they underwent simultaneous cataract surgery. The primary outcome was visual acuity at 6 months. Visual acuity at 3, 12, and 24 months, 3, 6, 12, and 24 month endothelial cell density and intraoperative and postoperative complications were also recorded.

RESULTS

Those who had pseudophakic EK generally were older, more likely to be male, and more likely to have worse baseline vision with higher corneal densitometry values. After controlling for baseline visual acuity and type of keratoplasty, those that underwent Triple-EK had 0.09 better LogMAR lines better visual acuity at 6 (95% CI -0.17 to -0.10; P = 0.02) and 12 months (95% CI -0.21 to -0.07; P = 0.03). Although those receiving Triple- EK had nearly one-half LogMAR line better visual acuity at 24 months, it was no longer statistically significant (95% CI -0.20 to -0.05; P = 0.36). There was no statistically significant difference in ECD between groups at any timepoint. Those undergoing triple EK were more likely to have at least one adverse event (P = 0.02).

CONCLUSIONS

Earlier intervention with Triple-EK may improve visual acuity outcomes after endothelial keratoplasty compared with staged procedures, but may also increase the risks of adverse events including the need for re-bubble.

Clinical observation of phacoemulsification under the low perfusion pattern and low negative pressure in patients with low corneal endothelial cell density

BACKGROUND

To observe the safety and effect of phacoemulsification combined with intraocular lens (IOL) implantation in patients with low corneal endothelial cell density (CD) under the low perfusion pattern with low negative pressure.

METHODS

In this retrospective case series study, a total of 16 patients (17 eyes) were studied. They had all been diagnosed with low corneal endothelial (CD) and cataracts in the First Affiliated Hospital of Fujian Medical University from December 2019 to October 2021. They underwent phacoemulsification combined with IOL implantation under the low perfusion pattern with low negative pressure. The variations of corneal endothelial( CD), coefficient of variation (CV) of the cell area, central corneal thickness (CCT), visual acuity, and intraocular pressure before and after the operation were observed and assessed. Then a paired t-test, repeated measures analysis of variance, and Pearson correlation analysis were adopted for data analysis.

RESULTS

The mean intraocular pressure of the 17 eyes was 16.88 ± 6.47 mmHg before the operation and 14.41 ± 3.10 mmHg after the operation, showing a statistically significant difference of t = 2.222, and p = 0.041. Before the operation, the mean visual acuity was 0.16 ± 0.09, and after the operation, it was 0.45 ± 0.16, displaying a statistically significant difference of t = -9.917, p < 0.001. Before and after the operation, four of the 17 eyes had no detectable CD. The mean CD of the other 13 eyes at one month after the operation (644.308 ± 106.24 cells/mm²) was lower than that before the operation (709.62 ± 119.19 cells/mm²), and the differences were statistically significant (F = 20.044, p < 0.001). However, no statistically significant differences were found in the mean CV before the operation (31.23 ± 4.21), and at one month after the operation (32.62 ± 3.80; F = 2.130, p = 0.157). Moreover, the mean CCT of 14 eyes at one month after the operation (562.72 ± 27.82 μm) was larger than that before the operation (534.79 ± 24.69 μm).

CONCLUSIONS

The low perfusion pattern with low negative pressure is safe and effective for corneal endothelial dysfunction patients complicated with cataracts.

Fuchs Dystrophy and Cataract: Diagnosis, Evaluation and Treatment

Corneal endothelium plays an important role in maintaining hydration homeostasis and clarity of the cornea. Fuchs endothelial corneal dystrophy (FECD) affects the corneal endothelium resulting in edema and characteristic excrescences on the Descemet's membrane known as corneal guttae. Descemet membrane endothelial keratoplasty (DMEK) has evolved to become the standard of care for patients with FECD with excellent visual acuity outcomes. Patients with FECD may have coexisting cataracts and therefore may require a cataract surgery, which increases the risk of corneal decompensation. The presence of FECD may not only influence the choice of intraocular lens but vision outcomes can also be affected by the corneal condition. The ability to combine the surgeries further raises important considerations regarding the timing and sequence of DMEK and cataract extraction for patients with FECD. This review provides a guide for corneal surgeons in choosing between endothelial keratoplasty and cataract surgery-alone, in combination or sequential-in their management of patients with FECD.

Cataract surgery and intraocular lens placement in patients with Fuchs corneal dystrophy: a review of the current literature

PURPOSE OF REVIEW

Late-onset Fuchs endothelial corneal dystrophy (FECD) is seen in approximately 4% of individuals over the age of 40. With the growing population of adults over the age of 65, ophthalmologists need to be aware of the preoperative, perioperative, and postoperative considerations involved in cataract surgery in Fuchs patients.

RECENT FINDINGS

Management of cataract patients with FECD requires preoperative assessment of endothelial cell size, density, and morphology. Considerations for perioperative endothelial cell loss include patients with hyperopia and shallow anterior chambers, phacoemulsification technique, transfer of ultrasonic energy to the cornea, corneal-protective perioperative agents, as well as thermal and mechanical damage.

SUMMARY

Ophthalmologists performing cataract surgery on patients with FECD must carefully consider the risks of endothelial cell loss during surgery and minimize the risk of corneal decompensation after surgery. Preoperative management should evaluate the severity of the FECD as well as individual factors such as cataract density, the health and thickness of the cornea, and the anterior chamber depth. Perioperative techniques, adjustments to biometry calculations, and intraocular lens (IOL) selection may help optimize visual outcomes and recovery time.

[Outcomes of cataract surgery in patients with Fuchs endothelial corneal dystrophy]

PURPOSE

While endothelial keratoplasty has become the standard treatment for Fuchs dystrophy, the strategy for first-line surgery in patients with associated cataract is still debated. The purpose of this study was to evaluate the surgical outcomes of eyes with Fuchs endothelial corneal dystrophy (FECD) undergoing phacoemulsification alone, to ascertain preoperative factors that predict the need for endothelial keratoplasty (EK).

METHODS

Single-center retrospective study. Cataract surgery alone was performed in 64 eyes of 50 patients with FECD. This decision was made if the patient did not have morning blur, the central corneal thickness (CCT) was below 630 microns, and endothelial cells were visible in the periphery.

RESULTS

Mean follow-up was 21 months (range 5-55 months). The mean preoperative CCT was 571±43μm. 6 months after surgery, it was 584±52μm (P=0.12). During follow-up, 14 eyes (22%) required an EK because of poor visual outcome after cataract surgery alone. Mean pre-operative CCT of these eyes (595±23μm) was significantly higher than eyes that did not require EK during follow-up (564±45μm, P=0.022). Over 570 microns, 34% of eyes required an endothelial keratoplasty after the cataract surgery alone.

CONCLUSIONS

CCT below 630μm associated with the absence of morning blur are preoperative criteria allowing 78.1% eyes with FECD to obtain good visual outcomes after cataract surgery alone. In these eyes, EK can therefore be avoided while ensuring good results.

Refractive Outcomes in Fuchs' Endothelial Corneal Dystrophy: Conventional and Femtosecond Laser-Assisted Cataract Surgery

Purpose

To investigate the refractive outcomes of eyes with Fuchs’ endothelial corneal dystrophy (FECD) following phacoemulsification.

Methods

This is a retrospective chart review of patients with FECD who underwent phacoemulsification. Manifest refraction at the early postoperative period (1–6 weeks) and late postoperative period (3–12 months) was collected. The spherical equivalent (SE) and variance of SE from target in diopters (D) were analyzed.

Results

A total of 219 eyes from 175 FECD patients (73 FLACS, 146 conventional phacoemulsification) were included. In the early postoperative period, when comparing variance from intended target, 62% (n=126) had a SE variance of ≤0.5 D, 22% (n=44) >0.5 D and ≤1 D, and 17% (n=34) >1 D. In the late postoperative period, 62% (n=85) had a SE variance of ≤0.5 D, 19% (n=26) >0.5 D and ≤1 D, and 20% (n=27) >1 D. There was no difference in the variance of SE comparing FLACS versus conventional phacoemulsification in either the early postoperative period (p=0.78) or the late postoperative period (p=0.29).

Conclusion

Patients with mild-to-moderate FECD had favorable refractive outcomes with phacoemulsification. There was no difference in refractive outcomes in eyes with FECD between the group that underwent FLACS versus the group that underwent conventional phacoemulsification.

Specular microscopy in clinical practice

Specular microscopy is a noninvasive diagnostic tool that allows for in vivo evaluation of corneal endothelium in health and various diseased states. Endothelial imaging helps in the diagnosis and management of several endothelial disorders. The review focuses on the principles of specular microscopy, limitations of endothelial imaging, and its interpretation in common conditions seen in the clinical practice. A thorough PubMed search was done using the keywords specular microscopy, corneal endothelium, and endothelial imaging.

Accelerated Corneal Endothelial Cell Loss after Phacoemulsification in Patients with Mildly Low Endothelial Cell Density

By evaluating preoperative endothelial cell density (ECD), ECD loss after phacoemulsification can be predicted. In this retrospective cross-sectional study, we compared outcomes of phacoemulsification with different levels of preoperative ECD. Three-hundred-and-fifty-three patients aged between 18 and 90 years received phacoemulsification at Chang Gung Memorial Hospital. Age (p = 0.003), preoperative logMAR (p = 0.048), cataract grade (p = 0.005), preoperative ECD (p < 0.001), operation time (p = 0.043), phacoemulsification time (p = 0.001), and phacoemulsification energy (p < 0.001) were significantly associated with postoperative ECD change (%). Patients were divided into three groups according to preoperative ECD levels. Level of ECD, coefficient of variation (CV), cell hexagonality (HEX), central corneal thickness (CCT), visual acuity, underlying diseases, and complications were analyzed. With regard to groups, 29, 71, and 252 patients were respectively allocated into the markedly low (group A; ECD below 1000 cells/mm²), mildly low (group B; ECD between 1000 to 2000 cells/mm²), and normal (group C; ECD above 2000 cells/mm²) ECD level groups. The highest CV (40.8 ± 13.9%; p < 0.001) and lowest HEX (58.4 ± 14.6%; p < 0.001) were found in group A. Significant ECD loss was found in group B (28.9 ± 9.2%) as compared to group A (19.9 ± 5.4%) and C (15.0 ± 12.0%) (p < 0.001). No significant differences were found with regard to changes in CV (p = 0.941), HEX (p = 0.937), CCT (p = 0.346), and logMAR (p = 0.557) among the three groups. In conclusion, preoperative ECD level could be a novel predictive value for postoperative cell loss, which was the most prominent in mildly low ECD level group. Less phacoemulsification energy, earlier surgical intervention, or novel topical medications could be suggested for patients with an ECD range from 1000 to 2000 cells/mm².

Femtosecond Laser-Assisted Cataract Surgery: Does It Improve Outcomes in Fuchs Endothelial Corneal Dystrophy?

The role of femtosecond laser -assisted cataract surgery in patients with Fuchs endothelial corneal dystrophy remains poorly defined. This invited commentary examines the current evidence surrounding this often-debated topic.

Long-term evaluation of endothelial cell changes in Fuchs corneal dystrophy: the influence of phacoemulsification and penetrating keratoplasty

PURPOSE

To evaluate the natural course of the long-term endothelial cell changes in Fuchs corneal dystrophy (FCD) patients and investigate the effects of phacoemulsification on the annual rate of change in endothelial indices in FCD patients.

METHODS

Thirty-four patients diagnosed with FCD at Seoul National University Hospital from 1994 to 2010 were retrospectively reviewed. Sixteen patients who had been followed up for more than 1 year were selected and classified into 3 groups: group A, patients with no ocular surgery; group B, patients who had undergone phacoemulsification only; and group C, patients who had undergone penetrating keratoplasty with cataract surgery. Endothelial cell density, polymegethism, pleomorphism, and pachymetry were measured and the exponential rates of endothelial cell and pachymetry change were analyzed.

RESULTS

A non-linear mixed model of non-operated FCD patients showed that only pachymetric data tended to increase with statistical significance (p = 0.001) with a mean follow-up period of 4.15 years. Using an exponential regression analysis fitting curve, the mean rates of annual endothelial cell loss were 0.82%/yr, 20.39%/yr, and 29.27%/yr in groups A, B, and C respectively, and statistical significance was seen only in group C (p < 0.05).

CONCLUSIONS

Retrospective long-term follow-up data showed that changes in endothelial density did not significantly decrease over at least 4 years in middle-aged FCD patients. The changes in pachymetric corneal thickness appeared to increase over the same period. Considering that no exponential changes were aggravated after performing cataract surgery alone, cataract surgery would be a preferable option in FCD patients compared to an approach of "wait-and-do" penetrating keratoplasty combined with cataract surgery.

Cataract surgery in eyes with low corneal endothelial cell density

PURPOSE

To compare corneal endothelial damage after cataract surgery in eyes with low endothelial cell density (ECD) and eyes with normal ECD.

SETTING

Hayashi Eye Hospital, Fukuoka, Japan.

DESIGN

Case-control study.

METHODS

Cataract surgery was performed in eyes with a low ECD (500 to 1000 cells/mm(2)) (low-density group) and control eyes with a normal ECD. The ECD and central corneal thickness (CCT) were measured preoperatively and 1 and 3 months postoperatively, and the percentage cell loss and increase in CCT were compared.

RESULTS

The low-density group and control group each comprised 50 eyes. In the low-density group, 39 eyes had nonprogressive endothelial pathology and 11 had Fuchs dystrophy. The mean ECD was significantly less and the CCT significantly greater in the low-density group than in the control group throughout the follow-up (P ≤.0066). However, no significant difference in the percentage of cell loss was found between groups at 1 or 3 months (5.1%, low-density group; 4.2%, control group) (P ≥.1477). The percentage increase in CCT was significantly greater in the low-density group than in the control group at 1 month (P<.0001), although there was no significant difference at 3 months (0.4% and -0.4%, respectively) (P=.2172).

CONCLUSION

Corneal endothelial damage after cataract surgery in eyes with low ECD was slight and comparable to that in healthy eyes, which suggests that cataract surgery alone (without corneal transplantation) should be performed first.