Luxación posterior bilateral del cristalino en una paciente agitada, ¿causa o consecuencia? / Posterior bilateral lens luxation in an agitated patient: Cause or consequence?

Las luxaciones posteriores completas del cristalino son entidades clínicas poco frecuentes. Los traumatismos son la principal causa de luxación secundaria del cristalino no iatrogénica. La mayor parte de los casos son unilaterales, siendo los casos de luxación bilateral muy poco frecuentes. Presentamos el inusual caso clínico de una mujer de 70 años que presentó una luxación bilateral posterior del cristalino en el contexto de un cuadro de instauración aguda de síndrome confusional. Discutimos acerca de la privación sensorial como un factor desencadenante de cuadros de confusión aguda y agitación en pacientes con enfermedades predisponentes. Además, describimos los beneficios que, en nuestra experiencia, nos aporta la técnica de reflotamiento con perfluorocarbono para el abordaje quirúrgico de estos casos

Complete posterior lens dislocation is an infrequent clinical entity. Trauma is the first cause of secondary lens dislocation. Most of the cases are unilateral, and bilateral cases are unusual. We report the uncommon case of a 70-year-old woman with evidence of a posterior bilateral dislocation of the lens in the context of an acute onset of confusional syndrome. We discuss about sensory deprivation as a trigger for acute confusion and agitation in patients with predisposing conditions. In addition, we describe the benefits that, in our experience, the refloating technique with perfluorocarbon liquid provides for the surgical approach to these cases

Case Series: Slight Intraocular Lens Malpositioning as a Potential Cause of Vision Loss.

SIGNIFICANCE: The cases illustrate an insidious cause of decreased visual acuity after cataract surgery. PURPOSE: The purpose of this study was to identify cases of postoperative vision loss caused by slight intraocular lens (IOL) malpositioning after cataract surgery. CASE REPORTS: Three patients presented with visual acuity decreased after cataract surgery. Silt-lamp examination before mydriasis revealed no abnormalities in two of the patients; mild IOL inferonasal decentration was found by the trifocal IOL diffraction ring in the third patient. Manifest refraction of these patients showed remarkable astigmatism with low corneal astigmatism. After pupil dilation, slight IOL decentration and tilt were observed in all patients, which were further confirmed using the Scheimpflug imaging system. Wavefront aberrometry showed a high level of ocular higher-order aberrations, most of which were derived from intraocular aberrations. CONCLUSIONS: Inconspicuous IOL malpositioning is one of the reasons responsible for decreased vision acuity after cataract surgery, which may not be easily identified by slit-lamp examination. High astigmatism and ocular higher-order aberrations derived from malpositioned IOL can be important clues.

Pathology and immunohistochemistry of capsular bag in spontaneously late dislocated capsular bag-intraocular lens complex.

PURPOSE: Our study aims to evaluate the morphology, histopathology, and immunohistochemistry of the spontaneously late dislocated capsular bag-intraocular lens (CB-IOL) complex. Various etiologies and possible pathogenesis of the event are also discussed. METHODS: This was a tertiary-care setting and retrospective observational case series. The surgically explanted intact specimens of spontaneously late dislocated CB-IOL complex were studied. The demographics, duration of pseudophakia, IOL design/material, and specimen measurements were noted. Fresh specimens were photographed, and computer software was used for measurements. After processing, a detailed microscopic examination was carried out for three different sections of each specimen with hematoxylin and eosin (H and E), Masson's-trichrome, and immunohistochemistry stain for vimentin. The Mann-Whitney U-test was used for the statistical analysis. RESULTS: Of 12 specimens, the mean CB and capsulorhexis opening size were 8.32 ± 0.8 mm and 3.62 ± 0.61 mm, respectively. The average CB-IOL complex size of our study was significantly lower than the studies reported in the literature (P ≤ 0.001). All (n = 12, 100%) were acrylic IOLs with 11 (91.67%) having single-piece design. All specimens on H and E stain showed extensive subepithelial fibrosis while Masson's trichrome staining showed that none had any pseudoexfoliation material. The circumferential sphincter-like fibrous tissue arrangement was seen in all specimens. Immunohistochemical expression of vimentin suggested the mesenchymal metaplasia of epithelial A-cells. CONCLUSION: Significant fibrotic contraction of the CB and phimosis of capsulorhexis may cause a progressive zonular tear. This is probably the most important etiology of spontaneous late dislocation of the CB-IOL complex.

Uveitis-Glaucoma-Hyphaema Syndrome. General review.

Uveitis-Glaucoma-Hyphaema Syndrome (UGH syndrome, or "Ellingson" Syndrome) is a rare condition caused by the mechanical trauma of an intraocular lens malpositioned over adjacent structures (iris, ciliary body, iridocorneal angle), leading to a spectrum of iris transillumination defects, microhyphaemas and pigmentary dispersion, concomitant with elevated intraocular pressure (IOP). UGH Syndrome can also be characterized by chronic inflammation, secondary iris neovascularization, cystoid macular edema (CME). The fundamental step in the pathogenesis of UGH syndrome appears to arise from repetitive mechanical iris trauma by a malpositioned or subluxed IOL. These patients have uncomplicated cataract implants and return for episodes of blurry vision weeks to months after surgery. This may be accompanied by pain, photophobia, erythropsia, anterior uveitis, hyphaema along with raised intraocular pressure. A careful history and examination, as well as appropriate investigations can confirm the diagnostic. Treatment options are IOL Explantation exchange, topical and systemic medication, and cyclophotocoagulation, the placement of a Capsular Tension Ring to redistribute zonular tension and Anti-vascular endothelial growth factor (anti-VEGF) Therapy.

Late in-the-bag intraocular lens dislocation in eyes with pseudoexfoliation syndrome.

PURPOSE: To assess preoperative features, frequency, surgical approaches and outcomes of late in-the-bag dislocation of posterior chamber intraocular lenses (IOLs) in eyes with pseudoexfoliation syndrome. METHODS: Seventy-seven patients (81 eyes) were enrolled. Inclusion criteria were patients with pre-existing pseudoexfoliation syndrome who underwent surgery for late in-the-bag IOL dislocation between March 2004 and April 2010. Medical records were reviewed. Data from before and after secondary surgery were analysed. RESULTS: Mean time between cataract extraction and secondary surgery for late in-the-bag dislocation of posterior chamber IOLs was 8.5 years. The increase in frequency within the reviewed period was statistically significant, ranging from six patients in the first year to 25 patients in the final year (p = 0.004). When surgical correction was performed within 1 month of referral, deterioration of the dislocation occurred in only one of 23 patients (4.3%). Complications, especially vitreous loss, occurred significantly more frequently during exchange surgery (n = 23) when compared with scleral suturing (n = 50) (p < 0.0001). After surgery, however, no differences in complications (p = 0.98) or best-corrected visual acuity (p = 0.74) was found. In general, following secondary surgery, there was a statistically significant improvement in best-corrected visual acuity (p < 0.0001). CONCLUSION: The frequency of late in-the-bag dislocation of posterior chamber IOLs in eyes with pseudoexfoliation syndrome increased during the observation period. Our study suggests that surgical repair should not be delayed beyond 1 month and that scleral suturing is preferable to exchange surgery, because of less intraoperative complications.

[Anterior chamber migration of a dexamethasone implant in a pseudophakic patient with a scleral-fixated posterior chamber intraocular lens]. / Migration d'un implant de dexaméthasone en chambre antérieure chez un patient pseudophaque porteur d'un implant de chambre postérieur suturé à la sclère.

We report the case of anterior chamber migration of a dexamethasone implant (Ozurdex(®)) in a 54-year-old woman with macular edema due to a central retinal vein occlusion. The patient had undergone complicated cataract surgery 5 years previously with a scleral-fixated posterior chamber lens implant. An uneventful intravitreal Ozurdex(®) implant injection was performed. One month later, the patient presented emergently with painless visual loss. Slit-lamp examination revealed the presence of discrete corneal edema associated with the implant in the anterior chamber. The implant was surgically removed from the anterior chamber 24 hours later with complete resolution of corneal edema.

[Anterior chamber migration of intravitreal dexamethasone implant (Ozurdex®) in pseudophakic eyes: report of three cases]. / Migration en chambre antérieure de l'implant intravitréen de dexaméthasone Ozurdex® chez le pseudophake: à propos de trois cas.

INTRODUCTION: Intravitreal implantation of Ozurdex(®) (Allergan Inc., Irvine, CA, USA) is being used widely for the treatment of macular edema secondary to retinal vein occlusion and in the setting of non-infectious posterior uveitis. We describe a complication little reported in the literature until now: migration of the dexamethasone implant into the anterior chamber. PATIENTS AND METHODS: We report three cases of migration in two pseudophakic patients with iris claw lenses (on the anterior and posterior aspects of the iris) and in one pseudophakic patient with a posterior chamber IOL and zonular rupture. DISCUSSION: The risk of anterior chamber migration of the Ozurdex(®) implant is increased in cases of prior vitrectomy (three cases), prone positioning and dilation of the pupil (mydriasis). Clinical tolerability of the implant in the anterior chamber is poor in all cases, with diffuse corneal edema. Endothelial cell loss occurs, as demonstrated by specular microscopy performed in two of our patients. Removal or repositioning of the Ozurdex(®) implant into the posterior segment must be performed without delay because of the risk of endothelial toxicity. CONCLUSION: Patients without perfect zonular/posterior capsular integrity present a high risk of anterior chamber migration of the Ozurdex(®) implant. In such cases, anti-VEGF therapies should be discussed as an alternative.

Modulation transfer function of a toric intraocular lens: evaluation of the changes produced by rotation and tilt.

PURPOSE: To evaluate the changes in optical quality when toric intraocular lenses (IOL) are rotated or tilted and to demonstrate that IOL rotation produces an increasing effect of aberrations. METHODS: Modulation transfer function (MTF) and average modulation were used to analyze the image quality of a toric IOL. The axis of the toric IOL was rotated 5°, 10°, 15°, 20°, 25°, and 30° in successive MTF measurements. The tilt values were 0° to 5°, in increments of 1°, plus a tilt of 15°. Pupil diameters of 3 and 5 mm were used. RESULTS: The MTF decay due to aberrations was more sensitive to rotation than tilt. The main decrement in the average modulation, of approximately 50% in both pupils, occurs when the IOL rotates from 0° to 5°. Between 0° and 1° tilt, the average modulation decreases approximately 25% for both pupils; with tilt >1°, the average modulation remains virtually unchanged. The points representing average modulation versus rotation angle are satisfactorily fitted by an exponential function, R=0.98. Average modulation versus tilt angle provides lower correlation degrees, R=0.91 and R=0.79, for 3- and 5-mm pupils, respectively. CONCLUSIONS: The MTF of the toric IOL decays with rotation and tilt, with greater decrement occurring in rotation from 0° to 5°. An asymptotic value exists in the average modulation decay, meaning that for angles higher than 15°, the average modulation of the toric IOL remains virtually constant.