Monika Udziela

In vivo confocal microscopy of corneal grafts shortly after penetrating keratoplasty.

Purpose To describe the microstructural status of corneal grafts shortly after penetrating keratoplasty (PK) and to evaluate the efficacy and safety of confocal microscopy in examining corneal grafts at that time. Methods A confocal microscope with a 40x front lens was used to examine corneal grafts in 32 patients (32 eyes) 4 days after PK. Images were analyzed, and endothelial cell density counts were compared with presurgical, eye bank values determined by specular microscopy. Results Microstructural alterations of the graft included epithelial and stromal edema, epithelial degeneration in both superficial and basal cell layers, dark stromal striae, activated keratocytes, and needle-like structures in the stroma. Descemet membrane folds were visible in 31 of 32 grafts; in 1 graft, the dense stromal edema did not allow imaging of posterior layers. Stromal nerve fibers were imaged in 28 grafts (88%). Endothelial cell density ranged from 1666 to 2548 cells/mm2 (mean±SD, 2125±283 cells/mm2); perioperative endothelial cell density loss varied from 0% to 29% (mean, 12%). No adverse reactions or signs of worsening of clinical condition were observed after the examination. Conclusions White light scanning slit confocal microscopy permits imaging of a grafts microstructure (including epithelium and stromal layers), as well as calculation of endothelium cell density, as soon as 4 days after PK. The most frequently observed morphologic alterations of corneal grafts shortly after PK include epithelial and stromal edema, epithelial degeneration, stromal striae, and Descemet membrane folds. Stromal nerves can still be seen in the graft 4 days after PK.

Fuchs Endothelial Corneal Dystrophy: Strong Association with rs613872 Not Paralleled by Changes in Corneal Endothelial TCF4 mRNA Level

Fuchs endothelial corneal dystrophy (FECD) is a common corneal endotheliopathy with a complex and heterogeneous genetic background. Different variants in the TCF4 gene have been strongly associated with the development of FECD. TCF4 encodes the E2-2 transcription factor but the link between the strong susceptibility locus and disease mechanism remains elusive. Here, we confirm a strong positive association between TCF4 single nucleotide polymorphism rs613872 and FECD in Polish patients (OR = 12.95, 95% CI: 8.63–19.42, χ 2 = 189.5, p < 0.0001). We show that TCF4 expression at the mRNA level in corneal endothelium (n = 63) does not differ significantly between individuals with a particular TCF4 genotype. It is also not altered in FECD patients as compared to control samples. The data suggest that changes in the transcript level containing constitutive TCF4 exon encoding the amino-terminal part of the protein seem not to contribute to disease pathogenesis. However, considering the strong association of TCF4 allelic variants with FECD, genotyping of TCF4 risk alleles may be important in the clinical practice.

Optical coherence tomography and in vivo confocal microscopy features of obstetric injury of the cornea.

We present a case of a 54-year-old man who reported to our department complaining of worsening vision and halos in the left eye. Slit-lamp biomicroscopy showed 2 distinctive oblique vertical lines situated on the posterior surface of the cornea. Anterior segment optical coherence tomography (AS-OCT) demonstrated bandlike structures protruding from the cornea into the anterior chamber for approximately 430 and 100 microm. In vivo confocal microscopy (IVCM) revealed stromal edema, low endothelial density, and prominent hyperreflective linear structures at the endothelium depth and behind the endothelium. The patient had a history of complicated, in-hospital, forceps-assisted delivery. The perinatal ophthalmic history was noncontributory. The fellow eye was healthy. We conclude that AS-OCT and IVCM are useful in confirming the clinical diagnosis of suspected perinatal corneal trauma because of the specific appearance of the Descemet membrane hypertrophic ridge in those examinations. There is a good correlation between the results of AS-OCT and IVCM.

Late-onset lattice corneal dystrophy without typical lattice lines caused by a novel mutation in the TGFBI gene.

Purpose: The aim of this study was to report the clinical, histopathological, and molecular findings in a patient with late-onset lattice corneal dystrophy (LCD) without typical lattice lines and a novel mutation in the TGFBI gene. Methods: Corneal lesions were visualized by slit-lamp examination and by in vivo confocal microscopy. Histopathological examination was performed on the patients corneal specimen obtained during a deep anterior lamellar keratoplasty. By using genomic DNA as a template, all coding regions of the TGFBI gene were amplified and directly sequenced. The presence of the mutation was verified using restriction endonuclease digestion. Eight different computational methods and multiple sequence alignments were used to predict the pathogenicity of the novel genetic variant. Results: The corneal phenotype was characterized by the presence within the stroma of round, oval, and short comma-shaped structures with indistinct margins. Lattice lines were not visible. Histopathological study revealed positive Congo red areas of amyloid deposits typical for LCD. A novel heterozygous missense mutation p.Leu565Pro was identified in exon 13 of the TGFBI gene. The amino acid substitution was unambiguously predicted to have a high pathogenic potential. Conclusions: The mutant codon 565 is located at the C-terminus in the region corresponding to a highly conserved amino acid in the fourth fascilin domain of the TGFBI protein. The novel variant expands the spectrum of TGFBI mutations causing LCD and located in this region. An increased number of known mutations will facilitate future studies of genotype–phenotype correlations and molecular pathogenesis of corneal dystrophies.

Clinical diversity in patients with Schnyder corneal dystrophy—a novel and known UBIAD1 pathogenic variants

PurposeSchnyder corneal dystrophy (SCD) is a rare inherited disease that leads to gradual vision loss by the deposition of lipids in the corneal stroma. The aim of this study is to report a novel pathogenic variant in the UBIAD1 gene and present clinical and molecular findings in Polish patients with SCD.MethodsIndividuals (n = 37) originating from four Polish SCD families were subjected for a complete ophthalmological check-up and genetic testing. Corneal changes were visualized by slit-lamp examination, anterior segment optical coherent tomography (AS-OCT), and in vivo confocal microscopy (IVCM).ResultsIn a proband with primarily mild SCD that progressed rapidly at the end of the fifth decade of life, a novel missense pathogenic variant in UBIAD1 (p.Thr120Arg) was identified. The other studied SCD family represents the second family reported worldwide with the UBIAD1 p.Asp112Asn variant. SCD in the remaining two families resulted from a frequently identified p.Asn102Ser pathogenic variant. All affected subjects presented a crystalline form of SCD. The severity of corneal changes was age-dependent, and their morphology and localization are described in detail.ConclusionThe novel p.Thr120Arg is the fourth SCD-causing variant lying within the FARM motif of the UBIAD1 protein, which underlines a high importance of this motif for SCD pathogenesis. The current study provides independent evidence for the pathogenic potential of UBIAD1 p.Asp112Asn and new information useful for clinicians.