Surgical outcome after phototherapeutic keratectomy in patients with TGFBI-linked corneal dystrophies in relation to molecular genetic findings.

PURPOSE: To evaluate the correlation between surgical outcome after phototherapeutic keratectomy in patients with autosomal dominant transforming growth factor, beta-induced (TGFBI)-linked corneal dystrophies (CD) and molecular genetic findings regarding the TGFBI gene. METHODS: Twelve patients were examined to investigate genotype by direct sequencing of the TGFBI gene. Twenty eyes of 12 patients were treated with phototherapeutic keratektomy (PTK) to remove superficial corneal opacifications and to decrease recurrent erosions. Surgical outcome, including visual improvement, recurrence of opacifications, postoperative complications, and additional therapeutic proceedings were reported and compared with the molecular genetic results. RESULTS: Four different missense mutations were identified within the coding region of the TGFBI gene: Arg124Cys in one eye, Arg555Trp in nine eyes, Arg124His in four eyes and Gly623Arg in six eyes. In all eyes the PTK was successful without clinically significant recurrent opacifications after a mean follow-up time of 17.6 months (min 3 months, max 42 months). The best corrected visual acuity (BCVA) improved with an average increase of 3.1 lines (minimum 2 lines, maximum 5 lines). In one eye (Arg124Cys), we observed delayed wound healing and a delayed increase in BCVA, in two eyes we performed an Epilasik to correct remaining hyperopia, and in four eyes we fitted rigid gas-permeable tricurve contact lenses to correct the remaining irregular astigmatism. CONCLUSIONS: The variable genotypes in patients with TGFBI-linked corneal dystrophies lead to significantly different results after surgical treatment. The Gly623Arg mutation seems to be an optimum genotype on which to perform PTK even in older patients. It is essential to determine the genotype in order to standardize the PTK treatment and to evaluate the success in TGFBI-linked corneal dystrophies.

Macular corneal dystrophy: mutational spectrum in German patients, novel mutations and therapeutic options.

INTRODUCTION: The objective of this study was to investigate genotype-phenotype correlations, the consequences for surgical treatment, and the therapeutical options in patients with macular corneal dystrophy (MCD). MATERIAL AND METHODS: We investigated MCD genotype by using polymerase chain reaction followed by direct sequencing in one family and four patients with MCD. Results were confirmed by restriction analysis. Clinical phenotypes, histopathological findings, and therapeutical proceedings of each patient were reported and compared with the molecular genetic results. RESULTS: Five mutations, four missense mutations, and one frameshift mutation, from which three were novel, and one single-nucleotide polymorphism, were identified within the coding region of the CHST6 gene. In three patients, two with a homozygous mutation within the start codon (Met1Leu) and one with a heterozygous mutation (Leu200Arg) and a polymorphism (Arg162Gly), with irregular corneal surface and recurrent erosions a phototherapeutic keratectomy lead to a transient success. An additional fitting of rigid gas permeable contact lenses in one patient could further improve irregular astigmatism. In two patients, one with a frameshift mutation (1734_1735delTG; Arg211Gln) and one with two compound heterozygous mutations (Leu200Arg; Leu173Phe) and an additional polymorphism (Arg162Gly) a penetrating keratoplasty improved BCVA without any recurrence of the opacities within the follow-up time. DISCUSSION: Different genotypes imply several phenotypes, which influence therapeutical proceedings in MCD patients. Our study shows the wide range of diagnostic findings and therapeutical options in patients suffering from macular corneal dystrophy depending on the genotype.