Iatrogenic ectasia

BACKGROUND: Secondary intracranial hypotension is a clinical syndrome associated with reduction of cerebrospinal fluid volume and dural continuity violation. The main symptoms are orthostatic headache associated with nausea, vomiting, diplopia, dizziness, and tinnitus. The treatment is usually nonspecific. CASE DESCRIPTION: A 37-year-old woman developed secondary intracranial hypotension caused by lumbosacral iatrogenic dural ectasia following detethering surgery...

PURPOSE: The purpose of this study is to evaluate ocular, corneal, and internal aberration parameters in eyes with keratoconus (KC), forme fruste keratoconus (FFKC), and normal eyes. METHOD: In a prospective study, one eye of 110 patients with KC, 60 FFKC patients, and 150 healthy participants was evaluated using OPD-Scan II. Ocular, corneal, and internal higher-order aberrations were measured through a sixth-order Zernike polynomial decomposition. Receiver operating characteristic analysis was performed to evaluate the diagnostic ability of the aberration parameters in discriminating KC and FFKC from normal eyes...

PURPOSE OF REVIEW: To identify and evaluate the risk factors of iatrogenic ectasia after refractive surgery. RECENT FINDINGS: We reviewed recently published papers that identified various risk factors associated with ectasia after LASIK, photorefractive keratectomy, small incision lenticule extraction, and other refractive surgical procedures. We also attempted to evaluate the relative contributions of these factors to the development of ectasia following refractive surgery...

OBJECTIVE: To perform a literature review of the current clinical applications of corneal collagen cross-linking. METHODS: An exhaustive literature search was made, including the main biomedical databases, and encompassing all years since the introduction of cross-linking in ophthalmology practice. RESULTS: Corneal collagen cross-linking using UVA irradiation and riboflavin is a surgical technique that is currently being optimised, and is supported by a good amount of pre-clinical and clinical studies...

PURPOSE: To design a technique for intrastromal transplantation of stromal lenticules with specific refractive power for correction of post-LASIK induced hyperopia and astigmatism. METHODS: A 28-year-old patient was referred for consultation after complicated LASIK for moderate myopia and astigmatism. The refractive error of the right eye was severely overcorrected due to data entry error. Post-LASIK refraction showed high astigmatism (right eye: +6.50 -9.00 @ 84°) and corrected distance visual acuity (CDVA) of 20/32...

Iatrogenic corneal ectasia is a rare but devastating complication after refractive surgery. While its incidence appears to be declining, it has not been eliminated. Its cause is probably related to a combination of an intrinsic predisposition to ectasia and an additional anatomical destabilising effect from the refractive surgery. Determining which eyes are intrinsically "weak" and exactly how much additional "weakening" an eye can withstand before developing progressive thinning and protrusion are both difficult tasks...

BACKGROUND: Corneal cross-linking (CXL) using ultraviolet light-A (UV-A) and riboflavin is a technique developed in the 1990's to treat corneal ectatic disorders such as keratoconus. It soon became the new gold standard in multiple countries around the world to halt the progression of this disorder, with good long-term outcomes in keratometry reading and visual acuity. The original Dresden treatment protocol was also later on used to stabilize iatrogenic corneal ectasia appearing after laser-assisted in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK)...

PURPOSE: To report a case of iatrogenic unilateral post-LASIK corneal ectasia with contralateral spontaneous ectatic evolution. METHODS: Case report with preoperative and postoperative measurements including uncorrected visual acuity, corrected distance visual acuity, refraction, slit-scanning topographic and pachymetric maps, and differential maps. RESULTS: Six months after unilateral LASIK, the operated eye progressively developed signs of post-LASIK ectasia with increased inferior corneal steepening and corneal thinning and decrease in corrected distance visual acuity...

Pentacam is a rotating Scheimpflug-based corneal and anterior segment tomographer that gives as comprehensive analysis of corneal 3D geometry. With this device the detection of mild keratoconus or ectasia susceptibility is possible. This is fundamental for screening ectasia risk prior to laser vision correction. The identification of susceptible cases at risk for developing progressive iatrogenic ectasia should go beyond (but not over) corneal front surface topography.

PURPOSE: Cultivated limbal epithelial stem cell transplantation (CLET) is a surgical approach reserved for severe stem cell deficiency and anterior segment pathology. The recipient cornea typically displays a highly vascularized pannus that must be dissected before graft placement. Extensive pannus dissection, however, can result in corneal thinning and increase the risk of ectasia and ultimately, of perforation. We aimed to examine the value of anterior segment optical coherence tomography (AS-OCT) intraoperatively during pannus resection and long-term postoperative follow-up of CLET surgery...

Techniques available for corneal lamellar refractive surgery are laser-assisted in situ keratomileusis (LASIK) using a microkeratome or femtosecond laser incision followed by excimer laser corneal ablation, and femtosecond laser-assisted refractive lenticule extraction (ReLEx). These treatments are nowadays considered to be safe and effective standard procedures for surgical correction of mild to moderate ametropia. Possible complications include too small or decentered optical zones, intraoperative flap cutting errors and postoperative inflammation (e...

PURPOSE: To evaluate 6-year results of standardized epithelium-off corneal collagen cross-linking (CXL) for treatment of progressive corneal ectasia. DESIGN: Prospective, consecutive, interventional case series. METHODS: Thirty-six eyes of 25 consecutive patients with documented progressive primary or iatrogenic corneal ectasia underwent CXL following the Siena protocol. The main outcome measures included uncorrected (UDVA) and corrected (CDVA) distance visual acuities, biomicroscopy and fundus appearance, topography-derived steep and flat keratometry (Kmax, Kmin), central corneal thickness (CCT), intraocular pressure with Goldmann applanation tonometer (GAT-IOP), and endothelial cell density (ECD), recorded at baseline and months 1, 3, 6, 12, 24, 36, and 72...

This article discusses corneal cross-linking (CXL) and how it transitioned from a modality for treating corneal ectatic disorders to an inventive means of treating infectious keratitis. Initially, CXL was successfully developed to halt the progression of ectatic diseases such as keratoconus, using the standard Dresden protocol. Later, indications were extended to treat iatrogenic ectasia developing after laser-assisted in situ keratomileusis (LASIK) and photo-refractive keratectomy (PRK). At the time, it had been postulated that the combination of ultraviolet light with riboflavin could not only biomechanically strengthen the cornea but also was capable of destroying living cells and organisms including keratocytes and pathogens...

Iatrogenic corneal ectasia is a rare complication but also one of the most feared situations that can occur after uneventful corneal laser surgery. Ectatic changes can occur as early as 1 week or can be delayed up to several years after LASIK. The actual incidence of ectasia is undetermined, an incidence rate of 0.04 to almost 2.8 % has been reported. Ectasia is most common following LASIK; however, cases have been reported following PRK and other corneal refractive procedures. Keratectasia shows progressive myopia, irregular astigmatism, ghosting, fluctuating vision and problems with scotopic vision...

PURPOSE: Corneal collagen crosslinking (CXL) is a relatively new technique to reduce the progression of keratoconus. The technique can be performed with or without complete debridement of the corneal epithelium. We describe a novel intermediate technique involving mechanical disruption of the epithelium, and evaluate its safety and efficacy. METHODS: The case notes of 128 eyes with progressive keratoconus or iatrogenic corneal ectasia who had undergone CXL using the epithelial disruption technique were retrospectively reviewed...

Isolated right ventricular (RV) infarction may occur during percutaneous coronary intervention resulting from selective occlusion of a ventricular branch of the right coronary artery (RCA). We present a case of a pure RV infarction without iatrogenic origin that at the initial electrocardiographic analysis was suggestive of a left anterior descending artery-related acute myocardial infarction. Coronary angiography results made us suspect thrombotic occlusion of a small branch of the ectatic RCA resulting from slow flow...

PURPOSE: To report the rate of postoperative ectasia after laser-assisted in situ keratomileusis (LASIK) with femtosecond laser-assisted flap creation, in a population of patients with no identified preoperative risk factors. METHODS: A retrospective case review of 1,992 eyes (1,364 patients) treated between March 2007 and January 2009 was conducted, with a follow up of over 4 years. After identifying cases of ectasia, all the patient charts were examined retrospectively for preoperative findings suggestive of forme fruste keratoconus (FFKC)...

OBJECTIVES: To evaluate the visual correction and clinical performance with scleral contact lenses (CL) for the visual rehabilitation of irregular astigmatism and to report the effect of brief wearing breaks on the wearing time and success rate. METHODS: A retrospective review was performed on consecutive patients who were fitted with scleral CL because of irregular astigmatism following failure of other optical corrections. Visual acuity (VA) and wearing times were abstracted...

PURPOSE: To assess the suitability of corneal anterior and posterior surface aberrations and pachymetry profile data to discriminate between eyes that later developed postoperative LASIK iatrogenic keratectasia and eyes that remained stable. METHODS: Ten eyes of five patients that later developed iatrogenic keratectasia and 245 control eyes of 245 patients with a stable postoperative LASIK follow-up of 12 months or more were included. Zernike coefficients from anterior and posterior cornea, data from corneal pachymetry profiles, and output values of discriminant functions (input from Zernike coefficients, pachymetry data, and age) were assessed for their usefulness to discriminate between preoperative eyes with iatrogenic keratectasia eyes and controls using receiver operator characteristic (ROC) curve analysis...

Laser in situ keratomileusis (LASIK) is now considered to be a safe and effective standard procedure for surgical correction of low to medium ametropia. Nevertheless, as in any other surgical intervention complex courses may occur in single rare cases. Possible complications include, but are not limited to, optically effective errors, such as too small or decentered optical zones as well as intraoperative flap cutting errors and postoperative complications, such as inflammation (e.g. diffuse lamellar keratitis, DLK), epithelial or flap folds, epithelial ingrowths or iatrogenic ectasia...