[Impact of prematurity on the optic nerve]. / Impact de la prématurité sur l'aspect morphologique et tomographique du nerf optique.

INTRODUCTION: Thanks to the progress made in the past few years in pediatric intensive care as well as the increased survival of preterm infants, the consequences of premature birth are increasingly well documented. With regard to ophthalmologic complications, retinopathy of prematurity is well described, but the optic nerve may also be affected. The goal of this study is to compare the optic nerves of preterm infants as a function of their gestational period with a control group of the same age. MATERIALS AND METHODS: We conducted a case-control study pairing a full-term infant with each preterm infant. Inclusion criteria were: any child from 5- to 10-years-old, separated into three sub-groups according to their degree of prematurity. Variables were: cup/disc ratio, ocular biometry, intraocular pressure and RNFL thickness. RESULTS: Thirty-seven preterm infants and 37 controls were included in the study. The mean age at the time of inclusion was 7.05 years for the preterm group and 7.19 years for the control group. No significant difference was observed in axial length or spherical equivalent (P=0.31 and P=0.98, respectively). No significant difference was observed in pachymetry or intraocular pressure (P=0.28 and P=0.22, respectively). We observed a significant increase of 0.1 in the cup/disc ratio of the preterm group compared to the control group (P<0.05). The preterm group cup/disc ratio was 0.36 versus 0.27 for the control group. No significant difference was observed in the 7 quadrants of RNFL between the two groups. However, when comparing infants born before 28 weeks gestation with the control group, we observed a mean decrease of 14.5 microns in the superior temporal sector (P=0.04), a 9 micron decrease in the global thickness G (P=0.03) and a 12.7 micron decrease in the nasal sector (P=0.01). CONCLUSIONS: In the case of the studied children (aged 5 to 10), the reduced RNFL fiber thickness is a phenomenon dependent essentially on the stage of prematurity. It would be useful to follow these preterm populations over the long term and to compare them to a matched control group to be able to obtain functional results.

[UT-DSAEK using grafts provided by a tissue bank, a one-year follow-up study of 79 grafts]. / UT-DSAEK avec greffons préparés en banque, suivi de 79 greffes sur un an.

INTRODUCTION: UT-DSAEK is a recent technique developed in order to obtain grafts thinner than a conventional DSAEK (less than 100 microns). The goal of this study was to evaluate the anatomic and clinical results over a period of one year for a retrospective series of UT-DSAEK procedures at the University Hospital of Nantes, using pre-cut grafts provided by a tissue bank, and to compare results with other existing techniques: DSAEK and DMEK. METHODS: In this retrospective, single-center study, all patients requiring an endothelial graft over a one-year period were included. The criteria studied were visual acuity, graft thickness, pachymetry and specular microscopy, recorded on the preoperative visit, D7, M1, M3, M6 and M12. RESULTS: Seventy-nine grafts were performed on 75 patients. The mean age was 72 years. Between the 7th day and the end of the first year, the graft thickness in the visual axis decreased from 75±29 to 60±21 microns rapidly over the first three months. The pachymetry decreased from 706±95 microns preoperatively to 561±54 microns with the same kinetics. The cell density of the graft decreased from 2604±13 cell/mm2 prior to the procedure to 1551±124 cell/mm2 (40% loss) at one year. The preoperative visual acuity was 1.16 logMAR, rapidly improving to 0.65 logMAR at the first month and 0.40 logMAR at one year. CONCLUSION: This study provides a fair amount of data on the progression of UT-DSAEK grafts: a decrease in graft thickness over the first three months, corresponding to an increase in visual acuity over this same period, with a good endothelial survival rate. This technique opens new avenues for the treatment of endothelial diseases, being complementary to DMEK in terms of surgical indications.