ABSTRACT
PURPOSE: To determine the incidence of and analyze risk factors for suction loss during femtosecond laser-assisted small incision lenticule extraction in the management of myopia or myopic astigmatism. SETTING: Roayah Vision Correction Center, Alexandria, Egypt. DESIGN: Retrospective comparative case-control study. METHODS: All eyes that had femtosecond laser-assisted small-incision lenticule extraction for the correction of myopia and myopic astigmatism performed between August 2010 and April 2014 were included. Eyes that developed suction loss were identified. Their characteristics, including demographic data (age and sex), eye laterality, manifest refraction, flat keratometry (K) reading, steep K reading, K astigmatism, optical zone, central corneal thickness, and corneal cap diameter and thickness, were compared with those in randomly selected control eyes to determine the risk factors for developing suction loss. RESULTS: Of the 3376 eyes that had femtosecond laser-assisted small-incision lenticule extraction during the study, 70 (2.1%) developed loss of suction. The incidence decreased with surgical experience (5.06% in 2010, 3.59% in 2011, 3.41% in 2012, 2.32% in 2013, and 1.84% in 2014), suggesting a learning curve. A multivariate logistic regression model showed that eyes with a larger cap diameter were significantly more likely to develop suction loss (P = .023; odds ratio, 9.60). CONCLUSIONS: Surgical experience significantly decreased the risk for suction loss during femtosecond laser-assisted small incision lenticule extraction for the correction of myopia or myopic astigmatism but did not eliminate it. A larger cap diameter significantly increased the risk for developing the suction loss. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.
Subject(s)
Corneal Stroma/surgery , Intraoperative Complications , Lasers, Excimer , Myopia/surgery , Suction , Adolescent , Adult , Astigmatism/surgery , Case-Control Studies , Corneal Pachymetry , Egypt/epidemiology , Female , Humans , Incidence , Intraoperative Complications/epidemiology , Learning Curve , Male , Microsurgery/methods , Middle Aged , Retrospective Studies , Risk Factors , Young AdultABSTRACT
BACKGROUND: Surgery of radiation-induced cataracts in children with retinoblastoma (RB) is a challenge as early intervention is weighted against the need to delay surgery until complete tumour control is obtained. This study analyses the safety and functional results of such surgery. METHODS: In a retrospective, non-comparative, consecutive case series, we reviewed medical records of RB patients ≤ 14 y of age who underwent either external beam radiotherapy or plaque treatment and were operated for radiation-induced cataract between 1985 and 2008. RESULTS: In total, 21 eyes of 20 RB patients were included and 18 out of the 21 eyes had Reese-Ellsworth stage V or ABC classification group D/E RB. Median interval between last treatment for RB and cataract surgery was 21.5 months, range 3-164 months. Phacoaspiration was performed in 13 eyes (61%), extra-capsular cataract extraction in 8 (39%) and intraocular lens implantation in 19 eyes (90%). The majority of cases, 11/21 (52%), underwent posterior capsulorhexis or capsulotomy and 6/21 (28%) an anterior vitrectomy. Postoperative visual acuity was ≥ 20/200 in 13 eyes and < 20/200 in 5 eyes. Intraocular tumour recurrence was noted in three eyes. Mean postoperative follow up was 90 months ± 69 months. CONCLUSIONS: Modern cataract surgery, including clear cornea approach, lens aspiration with posterior capsulotomy, anterior vitrectomy and IOL implantation is a safe procedure for radiation-induced cataract as long as RB is controlled. The visual prognosis is limited by initial tumour involvement of the macula and by corneal complications of radiotherapy. We recommend a minimal interval of 9 months between completion of treatment of retinoblastoma and cataract surgery.