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Purpose: Fuchs' endothelial corneal dystrophy (FECD) has been considered a genetically heterogeneous disease but is increasingly associated with the transcription factor 4 (TCF4) gene. This study investigates the prevalence of the cytosine-thymine-guanine (CTG)n repeat expansion in TCF4 among FECD patients in northern Sweden coupled to the phenotype.

Methods: Blood samples were collected from 85 FECD cases at different stages. Short tandem repeat PCR and triplet repeat-primed PCR were applied in order to determine TCF4 (CTG)n genotype.

Results: A (CTG)n repeat expansion (n > 50) in TCF4 was identified in 76 of 85 FECD cases (89.4%) and in four of 102 controls (3.9%). The median (CTG)n repeat length was 81 (IQR 39.3) in mild FECD and 87 (IQR 13.0) in severe FECD (p = 0.01). A higher number of (CTG)n repeats in an expanded TCF4 allele increased the probability of severe FECD. Other ocular surgery was overrepresented in FECD cases without a (CTG)n repeat expansion (44.4%, n = 4) compared with 3.9% (n = 3) in FECD cases with an (CTG)n repeat expansion (p < 0.001).

Conclusion: In northern Sweden, the FECD phenotype is associated with (CTG)n expansion in the TCF4 gene, with nearly 90% of patients being hetero- or homozygous for (CTG)n expansion over 50 repeats. Furthermore, the severity of FECD was associated with the repeat length in the TCF4 gene. Ocular surgery might act as an environmental factor explaining the clinical disease in FECD without a repeat expansion in TCF4.

Purpose: To study the impact of corneal guttata on postoperative visual acuity and patients' self-assessed visual function after cataract surgery.

Setting: Patient data from 49 Swedish cataract surgery units.

Design: Retrospective cross-sectional register-based study.

Methods: Data from patients who had cataract surgery from 2010 to 2017 and completed the Catquest-9SF questionnaire were obtained from the Swedish National Cataract Register. Logistic proportional odds regression was used to model the impact of corneal guttata on the visual acuity and self-assessed visual function. Adjustments were made for age, sex, ocular comorbidities, days to follow-up, preoperative corrected distance visual acuity (CDVA) and preoperative Rasch person score. The main outcome measures were postoperative CDVA and Rasch person score calculated from the Catquest-9SF questionnaire.

Results: The study comprised data from 33 741 patients. Cataract surgery greatly improved CDVA and self-assessed visual function in patients both with and without corneal guttata. Still, corneal guttata was significantly associated with a poorer visual acuity and a worse self-assessed visual function after cataract surgery. The negative effect of corneal guttata on visual acuity was most prominent during the first 3 weeks postoperatively, but it persisted at least 3 months postoperatively.

Conclusions: Patients with corneal guttata benefit substantially from cataract surgery but have an additional risk for inferior results compared with patients without corneal guttata. These findings could serve as valuable tools in clinical practice, in particular, when deciding to perform cataract surgery and how to inform the patient about surgical benefits and risks.

Purpose: To investigate the risk for corneal transplantation after phacoemulsification related to corneal guttata.

Setting: Forty-nine Swedish cataract surgical units and 7 Swedish cornea transplantation units.

Design: Registry-based cohort study.

Methods: Patient data from the Swedish National Cataract Registry between 2010 and 2012 were linked with data from the Swedish Cornea Transplant Registry between 2010 and September 2017. Data from cataract patients were linked with data from patients who underwent corneal transplantation because of endothelial failure. Triple procedures and other surgical methods for cataract extraction other than phacoemulsification were excluded. If both eyes had surgery, 1 eye was randomly selected from the registry to obtain unrelated samples. The incidence was calculated per 10 000 person years, and Poisson regression analysis was used to investigate the risk for corneal transplantation because of endothelial failure after phacoemulsification.

Results: Altogether, data from 276 362 cataract patients were linked with data from 2091 patients who underwent corneal transplantation. The incidence rate of corneal transplantation after phacoemulsification among patients with corneal guttata was 88 per 10 000 person years (95% CI, 74.5-103.1). The annual incidence rate was highest within the first year and diminished thereafter. The incidence rate of corneal transplantation among patients without corneal guttata was 1.4 per 10 000 person years (95% CI, 1.2-1.6). Phacoemulsification in patients with corneal guttata was associated with corneal transplantation with an adjusted relative risk of 68.2 (95% CI, 54.0-86.2).

Conclusions: The relative risk for corneal transplantation after phacoemulsification was 68.2 times higher for patients with corneal guttata than that for those without. Still, most of the patients with corneal guttata did not undergo corneal transplantation during the study period.

PURPOSE: To study the risk for corneal transplantation after phacoemulsification with dense cataract or posterior capsule rupture (PCR) and the impact of corneal guttata.

SETTING: Forty-nine Swedish cataract surgical units and 8 Swedish cornea transplantation units.

DESIGN: Registry-based cohort study.

METHODS: Patient data from the Swedish National Cataract Registry (2010 to 2012) were linked with data from the Swedish Cornea Transplant Registry (2010 to 2017). The outcome measures were risk for future corneal transplantation, visual acuity, and self-assessed visual function after phacoemulsification. Logistic and Poisson regression analyses with adjustment for confounder effects were used to investigate the association of the outcome measures with dense cataract, indicated by trypan blue capsular staining (TB) and PCR, separately and together.

RESULTS: Altogether, data from 276 362 cataract patients were linked with data from 2091 patients with endothelial failure who underwent corneal transplantation.The risk for future corneal transplantation increased more than 3-fold with the presence of dense cataract or PCR, and a trend toward an ever-higher risk with the combination of TB and PCR together, but without any significant synergy of corneal guttata. Dense cataract, but not PCR, was significantly associated with an increased probability of inferior visual acuity after phacoemulsification. The impact on satisfaction was not statistically significant for any of the factors.

CONCLUSIONS: Challenging cataract surgery increases the risk for future corneal transplantation equally in patients both with and without corneal guttata, despite a more vulnerable endothelium in the guttata group. This supports a strategy where PCR is limited and handled optimally and that cataract surgery is performed before the cataract turns critically dense.