Ri Barraquer

Interferón alfa 2-β, queratectomía parcial y trasplante de membrana amniótica para el tratamiento de un carcinoma escamoso conjuntival recidivante

CASE REPORT An 80-year-old woman diagnosed with a recurrent squamous conjuctival carcinoma treated with surgical excision of the lesion, zonal reconstruction and topical Interferon alpha 2-β. DISCUSSION Squamous conjunctival carcinoma is the most frequent neoplasm of the ocular surface. Surgical removal of the lesion is the traditional treatment, but this technique has a high recurrence rate. Interferons are glycoproteins that trigger intracellular pathways with antiviral and antitumoral properties. Recent studies have proven their activity against conjunctival carcinoma.

Intraocular stray light compared with subjective lens grading scores in normal and cataractous eyes

A European project studying the prevalence of visual function impairment in European drivers (2422 subjects) showed that intraocular stray light correlates with cataract grading scores. Measured intraocular stray light increases continuously with cataract severity, as estimated by the mean of the LOCS score (average of nuclear colour, nuclear opacity, cortical opacity and posterior subcapsular scores divided by four). Mean intraocular stray light for the lowest LOCS score (0.025) is about 1.00 log[s] and with a LOCS score for severe cataract (> 0.75) about 1.44 log[s]. This corresponds to a more than threefold increase in stray light. The lowest levels of intraocular stray light are found in nuclear cataracts (1.19 log[s]), followed by cortical (1.20 log[s]) and posterior subcapsular cataract (1.23 log[s]). Mixed nuclear and cortical cataracts have a mean of 1.30 log[s] and mixed nuclear, cortical and posterior subcapsular cataract a mean of 1.35 log[s]. A study in patients before lens surgery at the Centro de Oftalmologia Barraquer (218 eyes) did not showed a significant relation between lens grading scores and intraocular stray light values. About 90% had nuclear cataracts with low to medium severity (LOCS score between 0.2 and 0.6) with a mean stray light of 1.46 log[s]. A few cases had cortical cataracts reaching inside the pupillary area or very minor posterior subcapsular cataracts. All studies showed a large variation of intraocular stray light values for similar cataract scores, ranging from 1.00 to 2.00 log[s]. This probably reflects the theoretical expected important discrepancy between the backscattered light (lens grading) and forward scattered light (measured intraocular stray light).

The use of electro optical materials to restore accommodation

Purpose We present a review of current developments to restore accommodation by means of electro optical materials embedded in glasses, contact lenses or intraocular lenses.

Posterior capsule surgery and posterior capsulorhexis

Purpose To review the available intraoperative maneuvers to reduce the occurrence of posterior capsule opacification (PCO) after cataract surgery, including lens epithelial cell aspiration (LECA), posterior capsular membrane removal (PCMR), and posterior capsulorhexis (PCRX).

Boston KPro experience in Barcelona

Purpose To describe the indications, intraoperative complications, post-operative complications and anatomical and functional results of Type I Boston keratoprosthesis at our eye center in Barcelona. Methods Retrospective interventional case series on 24 eyes of 22 patients who underwent Boston keratoprosthesis implant from May 2006 to May 2008. Results The main indication for Boston keratoprosthesis implantation was a repeated failed graft (mean = 2.33 previous grafts). The most common principal pathologies were: bullous keratopathy, herpetic keratitis, aniridic keratopathy, corneal ectasia, calcific band keratopathy. No major intraoperative complications were noted and average time of surgery was 47 minutes. The mean follow-up time was 7.42 months. The major post-operative complications encountered were retroprosthetic membrane in 2 eyes, endophthalmitis in 2 eyes and corneal graft melting in 1 eye. The mean best corrected visual acuity improved from 0.015 pre-operatively to 0.1 post-operatively. Only one case of extrusion due to melting was encountered which was resolved by a reimplantation of the keratoprosthesis. Conclusion Our short-term experience with the type I Boston Keratoprosthesis is a good alternative for patients with repeated graft failures. Improvement in visual acuity is immediate and only minor complications were encountered.

Corneal molding and crosslinking

Purpose: To develop an experimental setup in human donor eyes to study the feasibility of combining corneal crosslinking (CCL) with molding techniques such as orthokeratology and intracorneal arcuate implants. Methods: 6 pairs of fresh human donor eyes with corneas unsuitable for transplantation but otherwise normal were maintained at constant 20 mm Hg intraocular pressure (IOP). The epithelium was removed and an orthokeratologic PMMA contact lens of 11.8 mm diameter and 10 mm main curvature radius was fixed to one cornea of each pair with 6 sutures of 9-0 vicyl. A standard CCL protocol (0.1 riboflavin phosphate, 370 nm UVA at 3 mW/cm2 for 30 minutes) was applied simultaneously to both corneas. We measured pre- and postoperative IOP, central pachymetry, corneal topography (EyeSys), corneal hysteresis (CH) and resistance factor (CRF) (ORA). Results: Average topographic cylinder (SimK) went from 1.66 diopters (D) to 2.01 D and from 1.55 to 1.06 D pre- to postoperatively, respectively in the orthoK-CCL and CCL-only corneas. Average maximal K value changed from 44.8 to 43.7 D in the orthoK-CCL and from 43.8 to 43.4 in the CCL-only group. None of these differences was statistically significant. Average CH went from 11.0 to 13.4 and from 9.0 to 13.7, respectively in the orthoK-CCL and CCL-only groups, while CRF went from 11.9 to 14.9 and from 10.7 to 14.6 respectively. Both groups showed a significant increase in pre- to postoperative CH and CRF, without significant differences between them. Conclusions: An experimental setup has been devised, able for testing combined CCL and corneal molding techniques in donor human eyes. Corneal molding by a sutured standard orthokeratology contact lens combined with CCL does not appear to induce a permanent change in corneal curvature parameters.