Zbynek Stranak

Spontaneous Closure of Patent Ductus Arteriosus in Infants ≤1500 g

Spontaneous PDA closure in VLBW infants is extremely prevalent. Infants born <26 weeks and 750 g, respectively, have a significantly higher rate of PDA at hospital discharge. OBJECTIVES: Patent ductus arteriosus (PDA) remains a challenging issue in very low birth weight (VLBW) infants, and its management varies widely. Our aim in this study was to document the natural course of ductus arteriosus in a cohort of VLBW infants who underwent conservative PDA management with no medical or surgical intervention. METHODS: A retrospective cohort study conducted in 2 European level-3 neonatal units. RESULTS: A total of 368 VLBW infants were born within the study period. Two hundred and ninety-seven infants were free of congenital malformations or heart defects and survived to hospital discharge. Out of those, 280 infants received truly conservative PDA management. In 237 (85%) of nontreated infants, the PDA closed before hospital discharge. The Kaplan-Meier model was used to document the incidence proportion of PDA closure over time for different gestational age groups. The median time to ductal closure was 71, 13, 8, and 6 days in <26+0, 26+0 to 27+6, 28+0 to 29+6, and ≥30 weeks, respectively. For different birth weight groups, the median was 48, 22, 9, and 8 days in infants weighing <750, 750 to 999, 1000 to 1249, and 1250 to 1500 g, respectively. No statistically significant relationship was found between PDA closure before hospital discharge and neonatal morbidities. CONCLUSIONS: The likelihood of PDA spontaneous closure in VLBW infants is extremely high. We provide in our findings a platform for future placebo-controlled trials focused on the smallest and youngest infants.

Clinical Outcomes after Complete Intracorneal Ring Implantation and Corneal Collagen Cross-Linking in an Intrastromal Pocket in One Session for Keratoconus

Purpose. The aim of this work was to evaluate the results after combined surgery implantation of full rings and CXL in one session in a group of patients with keratoconus during a 12-month follow-up. Material and Methods. The study included 22 eyes of 20 keratoconic patients, mean age of 28.41 (from 18 to 50) years. A full ring was inserted and afterwards 0.1% riboflavin solution was injected into the corneal pocket through the incision tunnel. The cornea was irradiated with UV-A light for 30 minutes. Postoperative visits were scheduled for the first week and months 1, 3, 6, 12, and 24 after surgery. Minimal follow-up time was 12 months. Results. The mean UDVA improved by 6 lines from before the operation to 1 year after the operation, the mean CDVA improved by approximately 2.5 lines, and the mean K improved by 3.94 D. Statistically significant reductions of sphere (P < 0.001), cylinder (P = 0.004), and spherical (P < 0.001) equivalents were found 1 month after surgery. Conclusion. The combined surgery MyoRing implantation and CXL seems to be a safe method in the treatment of keratoconus. We noticed an improvement of the refractive error in all of our patients.

Endothelial Wound Repair of the Organ-Cultured Porcine Corneas

ABSTRACT Purpose: To assess whether injured porcine endothelium of small and large corneoscleral disc differ in its reparative/regenerative capacity under various conditions of organ culture storage. Material and methods: 166 paired porcine corneas were trephined to obtain tissues with diameter 12.0 mm and 17.5 mm (with area neighboring endothelial periphery). In tested discs, central endothelium was mechanically wounded. Density of live endothelial cells (LECD), percentage of dead cells (%DC), coefficient of variation and cell hexagonality were assessed in central and paracentral endothelium following 5- or 9-day incubation in medium with 2% or 10% fetal bovine serum. The parameters were assessed also in fresh and intact cultured discs. Dead endothelial cells (EC) were visualized by trypan blue, cell borders by Alizarin Red S dye. Endothelial imprints were immunoassayed for the proliferation marker Ki-67 and the nucleolar marker fibrillarin. Results: In fresh corneas, the LECD/mm2 (mean ± standard deviation) were 3998.0 ± 215.4 (central area) and 3888.2 ± 363.1 (paracentral area). Only the length of storage had significant effect on wound repair. Lesion was repaired partially after 5-day and fully after 9-day cultivation. After 9-day storage in medium with 10% serum, the mean LECD detected in small discs were 2409.4 ± 881.8 (central area) and 3949.5 ± 275.5 (paracentral area) and in large discs the mean LECD were 2555.0 ± 347.0 (central area) and 4007.5 ± 261.2 (paracentral area). Ki-67 showed cell proliferation associated with healing of EC of both large and small corneas. Conclusions: The lesions were completely repaired within 9 days of storage. Presence of the area, where stem cells appear to be located, contributes to stimulation of endothelial reparation less than serum concentration and time of culture. Both cell migration and proliferation contribute to the wound repair.

25-gauge vitrectomy and gas for the management of rhegmatogenous retinal detachment

AIMS To evaluate the anatomical and functional results in patients with rhegmatogenous retinal detachment (RRD) who underwent 25-gauge pars plana vitrectomy (PPV) with gas tamponade. MATERIALS AND METHODS A retrospective evaluation of 126 eyes of 126 patients (79 men, 47 women) with RRD who underwent 25-gauge PPV with gas tamponade (13% C3F8 in 87 eyes, 20% SF6 in 39 eyes). 113 patients (89.7%), were operated on under local anaesthesia, 13 patients (10.3%) under general anaesthesia. Macula was detached in 85 eyes (67.5%). 53 eyes had pseudophakic RRD, 73 eyes were phakic. Anatomical success of the primary intervention, change in best corrected visual acuity (BCVA) and incidence of complications were assessed. An average follow-up period is 7.2 months (6-15). RESULTS With single operation, retinal attachment was achieved in 125 eyes (99.2%); the final anatomical success was 100%. The initial mean BCVA was 0.89 logMar (2.00 to 0.00); at the end of the follow-up period, it improved to 0.23logMAR (1.00 to -0.10), P < 0,0001. During the first post-intervention day, hypotony of the eye below 10 mmHg was observed in 1 patient (0.8%); on the contrary, intraocular pressure was temporarily increased to 25 mmHg and more in 36 patients (28.6%). CONCLUSION The surgical treatment of RRD using 25-gauge PPV with expansive gas tamponade renders excellent anatomical results and improvement in BCVA. The incidence of complications and necessity of sclerotomy suturing are low.