1,720,968 research outputs found
Pentacam Assessment of Posterior Lamellar Grafts to Explain Hyperopization after Descemet's Stripping Automated Endothelial Keratoplasty
No full textPurpose: To evaluate changes in posterior corneal curvature as a possible cause of the hyperopic refractive shift observed after Descemet's stripping automated endothelial keratoplasty (DSAEK). Design: Prospective, noncomparative, interventional case series. Participants: Thirty-four eyes of 29 patients with Fuchs' endothelial dystrophy or pseudophakic bullous keratopathy. Methods: A standard DSAEK procedure was performed in 34 eyes using the pull-through technique for graft delivery. When cataract was present (n = 7), phacoemulsification with posterior chamber intraocular lens implantation was combined. Each eye underwent Pentacam (Oculus, Wetzlar, Germany) evaluation 1, 3, and 12 months after surgery. Corneal graft thickness was calculated on Scheimpflug scans at 9 locations (1 central, 4 peripheral, and 4 mid peripheral). The mean radius of posterior corneal curvature (Rm) was recorded. At each postoperative examination time, manifest refraction was determined and compared with pre-DSAEK values in simple procedures or with intended postoperative refraction, if cataract surgery had been performed. Main Outcome Measures: Manifest refraction, Rm, and corneal graft thickness at 1, 3, and 12 months after surgery. Results: The mean±standard deviation posterior corneal curvature was 6.5±0.56 mm before surgery and varied from 5.52±0.39 mm 1 month after surgery to 5.83±0.37 mm at 3 months after surgery and 5.92±0.35 mm at 12 months after surgery. The grafts were significantly thicker in the periphery and mid periphery than in the center at all examination times. Thickening diminished significantly over time at all locations. The average reduction of corneal thickness was higher at the edges (91.5 Î1⁄4m) than in the mid periphery (38.3 Î1⁄4m) or in the center (24.2 Î1⁄4m). The average postoperative spherical equivalent±standard deviation changed from -0.31±2.35 diopters (D) before surgery to 1.03±2.21 D 1 month after surgery, 0.61±2.07 D 3 months after surgery, and +0.31±2.03 D 12 months after surgery. Conclusions: The difference in thickness between center and periphery of the DSAEK graft induces a change in posterior corneal curvature, resulting in a hyperopic shift that decreases with time and is negligible for spectacle correction. However, when performing a triple procedure, intraocular lens selection should take into account the refractive change induced by DSAEK
Surgical technique for graft exchange after big-bubble deep anterior lamellar keratoplasty
No full textPurpose: The aim of this study was to describe a surgical technique for repeat deep anterior lamellar keratoplasty (DALK) by baring Descemet membrane again in eyes affected by stromal opacity of the donor lamella. Methods: Repeat DALK was performed in 5 eyes of 5 patients affected by central stromal opacity not involving the endothelium; indications for repeat surgery were postbacterial or postherpetic corneal scars (n = 3), postphotorefractive keratectomy haze (n = 1), and recurrence of granular dystrophy (n = 1). The surgical procedure consisted of the following: (1) superficial trephination, 250 mm in depth, on the original peripheral scar; (2) blunt detachment of the donor graft completed by means of corneal forceps; (3) apposition of the new lamella. Best spectacle-corrected visual acuity, topographic astigmatism, and endothelial cell density were evaluated preoperatively, as well as 3, 6, 9, 12, and 18 months after surgery. Results: At the latest follow-up examination, with all sutures removed from all eyes, the best spectacle-corrected visual acuity was 20/30 or better in all cases with 3 eyes achieving 20/20. Postoperative refractive astigmatism averaged 3.0 6 1.2 diopters (mean 6 SD); endothelial cell density was not significantly affected by surgery. Conclusions: Repeat DALK is effective in removing diseased corneal stroma while keeping the recipient endothelium unaffected; the procedure is simple and does not require pneumatic dissection, thus eliminating the most challenging surgical step; postoperative visual recovery does not differ from that experienced after primary DALK
VALUTAZIONE STATISTICA SULLE VARIAZIONI TONOMETRICHE INDOTTE DA BETABLOCCANTI IN PAZIENTI GLAUCOMATOSI
No full textVALUTAZIONE SULLA TERAPIA FARMACOLOGICA ANTINFIAMMATORIA NON STEROIDEA IN PAZIENTI SOTTOPOSTI AD INTERVENTO DI CATARATTA CON IMPIANTO DI IOL IN CP Evaluation of a non-steroid anti-inflammatory therapy in patients submitted to cataract extraction with I.O.L. implantation in the posterior chamber
No full textVALUTAZIONE CLINICA E CONSIDERAZIONI FISIOPATOLOGICHE COMPARATIVE NELL'USO TOPICO DI ALCUNI BETABLOCCANTI NEL GLAUCOMA CRONICO SEMPLICE
No full textVALUTAZIONE SULLA TERAPIA FARMACOLOGICA ANTINFIAMMATORIA NON STEROIDEA IN PAZIENTI SOTTOPOSTI AD INTERVENTO DI CATARATTA CON IMPIANTO DI IOL IN CAMERA POSTERIORE
No full textL'IMPIANTO DI CRISTALLINO ARTIFICIALE NELLA CHIRURGIA DELLA CATARATTA TRAUMATICA IN ETA' INFANTILE
No full textVALUTAZIONE CLINICA E COMPARAZIONE DELL'EFFICACIA IPOTENSIVA DEL BEFUNOLOLO TIMOLOLO LEVOBUNOLOLO E PLACEBO NELLA TERAPIA DEL GLAUCOMA AD ANGOLO APERTO A clinical valuation and comparison of the ocular-hypotensive efficacy of befunolol versus timolol levobunolol and placebo in the treatment of the open angle glaucoma
No full textRed Reflex-Guided Big-Bubble Deep Anterior Lamellar Keratoplasty: A Simple Technique to Judge Dissection Depth
No full textPurpose: To report the results of a modified big-bubble deep anterior lamellar keratoplasty technique using the intraoperative red reflex to visualize the amount of residual stroma beneath the inserted cannula. Methods: A total of 132 consecutive keratoconic eyes were included in this retrospective, noncomparative, interventional case series. Before starting surgery, pharmacologic mydriasis was induced in all eyes undergoing a big-bubble deep anterior lamellar keratoplasty procedure. After partial trephination of the recipient cornea, a spatula was inserted at the base of the incision and advanced into depth using as a reference the thin dark line seen in the red reflex ahead of the advancing tip; the stromal depth reached was measured using anterior segment optical coherence tomography. Finally, the spatula was exchanged for a 27-gauge cannula, and air was injected to create a big bubble. The stromal depth reached with the spatula, success rate of big-bubble formation, and complications were recorded. Results: The big bubble was obtained in 118 of 132 eyes (89.4%). Of the remaining 14 eyes, 11 underwent completion of the procedure by manual dissection and 3 were converted to penetrating keratoplasty because the bubble burst while trying to enlarge it. Perforation did not occur in any case during cannula insertion. The average thickness reached with the stromal dissection was 64.3 ± 19.5 m. Conclusions: The thin dark line, seen in the red reflex obtained with pharmacologic dilation, provides a useful and effective reference that can be used to visualize and judge the depth of dissection, thus allowing a safer and reproducible approach to the pre-Descemetic stroma. Â
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