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Introduction: iterative penetrating keratoplasty procedures (PKPs) increase the risk of graft rejection. Surgeons are reluctant to perform a third procedure following two previous graft failures. We evaluated the outcomes of patients who had three successive PKPs treated with a local combination of cyclosporin 2% A and dexamethasone 0.1% eye drops., Patients and Methods: this is a retrospective study of a series of cases including 15 eyes of 15 patients treated and followed in the ophthalmology unit at the Hôtel-Dieu Hospital in Paris (2006-2009)., Results: after an average follow-up of 20.5±2 months, the risk of transplant rejection was 13.33% and the duration of follow-up corresponded in all patients to the duration of treatment with cyclosporin eye drops. The treatment was not interrupted by any patient because of intolerance., Conclusion: in this study, we observed a success rate justifying the indication of the third keratoplasty under local cyclosporin 2% classically considered debatable., (2010. Published by Elsevier Masson SAS.)

Purpose: To quantify the visual outcome obtained in patients operated on for penetrating keratoplasty for keratoconus (KC) after 1 and 2 years., Patients: and methods: The files from consecutive keratoconus patients operated on for PKP after more than 2 years of follow-up were retrospectively studied. The demographic charts, the KC stage, and the surgical features were noted. The best corrected visual acuities (BSCVA) were analyzed at the initial examination and after 1 and 2 years of follow-up., Results: One hundred and two eyes from 98 patients were analyzed, including 83 grade 4 (81%) and 19 grade 3 (18%) cases of KC. The mean preoperative BSCVA was 0.08 on the decimal chart, which increased to 0.5 and 0.6 1 and 2 years after penetrating keratoplasty (p<0.001, respectively). The mean keratometric astigmatism was 3.80+/-2.9 D and 3.94+/-2.3 D for the grade 3 and 4 KC, respectively, after 1 year and 2.52+/-1.9 D and 3.34+/-2.2 D after 2 years (NS). At this time point, 81% of the eyes had less than 5 D astigmatism., Conclusion: One and 2 years after penetrating keratoplasty, a mean BSCVA of 0.5 and 0.6 could reasonably be expected in keratoconus patients and three-quarters of patients can be expected to see better than 0.5 after 2 years.

Purpose: Early treatment of amebic stromal keratitis can change patients' final visual and esthetic prognosis. The aim of this study was to review all proven Acanthamoeba stromal keratitis cases presenting at our ophthalmology emergency department over the past 3 years, in order to delineate the incidence and the factors still leading to this serious complication., Patients: and methods: All cases of Acanthamoeba stromal keratitis confirmed with a parasitology examination and treated between January 2000 and December 2002 were recorded. During this period of time, eight patients were identified with this condition. Their charts, as well as biomicroscopic, therapeutic, and outcome data were analyzed., Results: All patients were referred in a second or third intention. Only one patient did not usually wear contact lenses. Six patients had an associated bacterial abscess. The typical amebic annular infiltrate was only observed in one patient. Three patients received an effective antiamebic treatment in the 15 days following the first symptoms and five patients 1 month or more after. An emergency keratoplasty was carried out in one patient. Finally, visual acuity was lower than 5/10 in all cases. The patients treated in the first 15 days had the best final visual acuity., Discussion: Soft contact lenses are still responsible for the majority of serious amebic corneal complications. Late diagnosis remains the main cause of Acanthamoeba stromal keratitis development, particularly in the absence of contact lens history, because of the delay in treatment., Conclusion: The catastrophic consequences of this complication justify a systematic treatment against ameba in each case of suspected diagnosis. An early and effective treatment of the stromal amebic keratitis can increase the final visual prognosis.

Introduction: The authors present the diode-pumped, all-solid state, neodymium:glass femtosecond laser from the Laboratory of Ocular Biotechnology, Hotel-Dieu Hospital., Materials and Methods: We worked with a 1,065-nm wavelength infrared laser. This laser is composed of an oscillator and amplification glass matrix mixed with neodymium. Its stretching and compression system is capable of producing pulses lasting a few hundred femtoseconds. The repetition rate is adjustable, ranging from 1 to 10 kHz, and can reach energies up to 60 microJ. The delivery system was set up on an optical table, with human corneal samples fixed to an anterior chamber system, which can be moved over the X-Y-Z axis by a computer-guided translation motor with micrometric precision. We analyzed the biological effects of laser impacts in human corneal tissue, obtained from the French Eye Bank., Results: The femtosecond laser provides automated corneal cutting with a high level of precision, which can be verified on the corneal surface regularity by scanning electron microscopy analysis. Silicon samples can also be cut and can be used for calibration testing of the laser., Conclusion: The set-up composed of the femtosecond laser and the described delivery system enable precise corneal cutting and offer the opportunity to study its characteristics.

Purpose: Cyclosporine administration is very effective in the case of immunological diseases of the cornea, conjunctive or uvea. Moreover, it is widely used in the case of high-risk rejection corneal transplantation. We present a preparation of cyclosporine 2% eye drops., Methods: Cyclosporine 2% eye drops are prepared following a particular formulation including one part commercially available cyclosporine oral solution (Sandimmun) diluted in four parts of sterile castor oil. Manufacturing procedures maintain the sterile state of the preparation with a laminar airflow hood placed in a particulate controlled room, with pharmacists, technicians and clerical personnel wearing sterile clothes. Physical and chemical monitoring during and after manufacture for each batch guarantees the process and minimizes the risk of batch rejection. Chemical analysis of cyclosporine is conducted using a validated stability-indicating high-performance liquid chromatographic assay (reverse-phase). Blood dosages taken after the first administration at the 24th hour (after administration of the 6th drop) check for systemic integration., Results: Cyclosporine 2% eye drops are fairly stable: 12 months after manufacturing, concentrations result in levels not statistically different from concentrations measured the day of preparation. After a daily regimen of six drops in the eye, cyclosporine 2% eye drops have a very low systemic bioavailability, because the blood concentrations only reach the detection limit of the fluorescence polarization immunoassay used for cyclosporine drug monitoring. This explains the absence of systemic toxicity., Conclusion: Cyclosporine 2% eye drops can be available in the hospital pharmacy. The eye drops are stable at room temperature and can be delivered up to 12 months after manufacture. No local adverse effects have been noted, probably in relation with the very low concentration of ethanol in the ocular preparation.

Pseudophakic bullous keratopathy is one of the most common complications of intraocular lenses, which explains the high rate of this condition in series of patients experiencing corneal grafts. It is caused by irreversible damage to the endothelial layer of the implanted eye involving the artificial lens, and occurs either during cataract extraction or after the operation. Intraoperative endothelial protection and the choice of an appropriate lens may contribute to decreasing this secondary disease, which can have severe consequences for many patients whose corneal graft may not restore their visual potential as well as expected. We report a clinicopathological case of a 59-year-old male, previously operated on for cataract in both eyes with an anterior chamber lens. A bilateral corneal edema occurred a few years after the operation, with a bilateral decrease in vision as a consequence. A corneal graft was performed in 2000 on the left eye in order to improve the patient's visual autonomy. The best treatment of this condition remains prevention, avoiding the use of this type of intraocular lens, whose main complication is corneal edema.

Purpose: Human amniotic membranes have recently been used in ophthalmology to restore deleted ocular surface after burns. Matrix metalloproteinases-2 and -9 have been implicated in the development of neovascularization. In this study, MMP-2 and MMP-9 expression was analyzed by in situ zymography on rabbit corneal chemical burns with and without human amniotic membrane graft., Method: Corneal neovascularization was induced in 10 Fauve de Bourgogne rabbits by means of a heptanol chemical burn on controlled deep keratotomy using a Chiron ALK-E corneal shaper. Half of rabbits received acute amniotic membrane transplantation 30mn after chemical burn; the remaining five rabbits received medical treatment. In situ zymography is a recent nondestructive technique which preserved the fine morphological details of the cornea and showed the active enzyme location in different corneal layers. The MMP-2 and -9 substrate was gelatin, which was detected by fluorescent microscopy., Results: There was an overexpression of MMP-2 and -9 in corneal burns versus control corneas. Expression of MMP-2 and -9 was low in corneal burn without amniotic membrane graft. Following amniotic membrane transplantation, MMP-2 and -9 were strongly expressed and clinical neovascularization and inflammation decreased. Active enzymes were located in epithelium layers in the uncovered group. In the covered group, the active enzymes were located in the anterior and posterior stromal layers., Conclusion: The results support a role for MMP-2 and MMP-9 in corneal burn neovascularization. Amniotic membrane transplantation can play a protective role by up-regulation of their biological expression.

Purpose: To study the tolerance of a silicone band wrapped with expanded polytetrafluoroethylene (e-PTFE) in "fauve de Bourgogne" rabbits., Methods: A 5.7mmx3.2mm band of S-PTFE (silicone-polytetrafluoroethylene, France Chirurgie Instruments) was used. A tight seal was produced between the two materials by silicone gluing. Eight eyes were implanted episclerally and fixed with Mersilene 5-0. One silicone band was used on a control eye., Results: Three eyes were removed at 4 weeks, one at 8 weeks and four at 12 weeks. No extrusion was observed except for the silicone band rejected 2 weeks after implantation. On histopathologic examination, PTFE colonisation was present in all eyes with fibroblast, inflammatory cells, and neovascularization., Conclusion: The S-PTFE implant was colonized and well tolerated in rabbit eyes. Advantages of silicone band (quality, stability of indentation) are combined to the tolerance of PTFE.

We report a French family suffering from an Avellino corneal dystrophy diagnosed by using clinical, histological, ultrastructural and genetics findings. Our results indicate that direct corneal examination and routine histological examinations must always be associated with an assay for BIGH3 gene mutations to establish a modern and unambiguous diagnosis of a corneal dystrophy.

Purpose: This retrospective study was designed to investigate the therapeutic potential of phototherapeutic keratectomy (PTK) for the treatment of band keratopathy., Patients and Methods: PTK was performed with the Excimed UV 200, (Summit Technology, Inc) on 27 eyes of 22 patients and with the Nidek EC5000 on 11 eyes of 10 patients with band keratopathy. Mean patient age was 57 years. The mean follow-up period was 19 months (ranged from 4 to 54 months). When possible, the change in best corrected visual acuity and spherical equivalent was evaluated at 6, 12, 18 and 24 months., Results: Almost 90% of patients with smooth bands achieved visual improvement and 85% of patients with rough bands improved ocular discomfort. The mean hyperopic shift caused by tissue ablation was less than +2.0D after one year, for smooth bands., Conclusion: Excimer laser PTK is a safe and effective outpatient treatment and should be used as initial treatment for band keratopathy.

Purpose: This study was designed to investigate the therapeutic potential of phototherapeutic keratectomy (PTK) for the treatment of corneal granular dystrophy., Patients and Methods: PTK was performed with the Excimed UV 200, (Summit Technology, Inc) on a series of 27 eyes of 22 patients with corneal granular dystrophy. Mean patients' age was 34.6 years. The mean follow-up period was 31 months (ranged from 6 to 52 months). The changes in best corrected visual acuity and spherical equivalent were evaluated at 6, 12, 18 and 24 months., Results: All of patients achieved visual improvement. Mean preoperative best corrected visual acuity (BCVA) was 20/100 and mean postoperative BCVA was 20/30 at one year. The mean hyperopic shift caused by tissue ablation was +/- 2.8 D after one year., Conclusion: Corneal grafting was the standard treatment for visually disabling granular dystrophy, but PTK has significant advantages over this procedure and must now be the standard method of managing corneal granular dystrophy when intervention is required.

A case of posttraumatic scleromalacia in a patient with Ehlers-Danlos syndrome is presented. The rare localization of the ocular rupture following a minimal trauma is discussed, as well as this scleromalacia treatment.

Cornea Plana is a bilateral and asymmetric congenital malformation of the corneo-scleral shape. Corneo-scleral lenses are said to be the preferential treatment. We reported the case of a 20-year-old woman, whose Cornea Plana was diagnosed at birth, with high hypermetropia and well-corrected with routine spectacles since she was 6 months old.

Purpose: Designed to avoid postoperative hypotony that often occurs after trabeculectomy and to maintain long lasting filtration, the MESH is a thin porous expended polytetrafluoroethylene (ePTFE) implant that mimics the physiological meshwork. The aim of this study is to assess the tolerance, biocompatibility and effectiveness of this device during 6 months in the rabbit., Material and Methods: We used an ePTFE with about 5 microns pore size (Zytex). The head of the implant is 3,0 mm wide and 1,5 mm long and fits in the anterior chamber. The tail is 2,0 mm wide and 3,0 mm long and fits in the subconjunctival space. The MESH is 250 microns thick. 24 Dutch pigmented rabbits were selected because their dark pigmented iris contrasts with the ePTFE implant giving a better visualization. All the animals were cared for in accordance with ARVO resolutions. Surgery was performed on the right eye by the same surgeon (P.H.), the left eye serving as control for IOP measurements. The animals were distributed in 3 groups: one with MESH alone (MESH), one with MESH and Mitomycin C (MMC), one with MESH and 5-FU (5-FU). Follow-up was performed every week (W) during 6 months including IOP measurement, slit lamp observation, photography and bleb assessment. Histological study was done at POD 0, 15, 30, 90 and 180 one eye in each group. Student t test and alternate Welch t test were used for statistics., Results: Filtering bleb: no bleb was visible before W3. A bleb was found between W3 and W6, decreasing between W6 and W9 with no more change after W10. The MESH implant: no change appears in the color of the MESH during the study. Some iris pigments or synechiae were seen in some cases. No extrusion occurred. Intraocular pressure: IOP was lower than in the control eye. The statistical analysis showed a significant lower pressure for the MESH alone at W5 (p = 0.0069), for the 5-FU group at W1 (p = 0.0326), W2 (p = 0.0488), W4 (p = 0.0312). With Mitomycine C we found very significant results at W1 (p = 0.0073), W2 (p = 0.0136), W4 (p = 0.0497), W9 and W11 (p = 0.0174). After W12 the groups were joined and IOP was significantly decreased at W17 (p = 0.0376) and W23 (p = 0.0462). Histology confirmed the correct position of the MESH, its biocompatibility and its ability to drain aqueous humor even if there is colonization of the pores by fibroblast-like cells., Conclusion: The present study has shown that the filtering bleb appeared after 3 weeks without major hypotony. The material was integrated only in the intrascleral tunnel and was stable. After 6 months the Mesh was well tolerated. The new concept has a simple surgical technique, less invasive than trabeculectomy and required less surgical time. This technique reduced IOP and produced long survival blebs in rabbits. This device appears suitable for the surgical treatment of open angle glaucoma.

Purpose: Evaluation of clinical tolerance and scanning electron microscopy study of the bio-colonisation of a porous ceramical alumina implant after evisceration of the rabbit. Preliminary results., Methods: Sixteen white New Zealand rabbits were eviscerated. A porous hydroxyde alumina ball was implanted in the opened sclera and explanted 15, 30, and 90 days after implantation. Clinical tolerance was assessed and implant tissular ingrowth was analyzed by scanning electron microscopy., Results: One infection was observed and there was no conjunctival breakdown. Fibrovascular ingrowth occurred as soon as 15 days after implantation, and was full at one month., Conclusion: Porous alumina implant orbital tissue tolerance and fast fibrovascular ingrowth in the rabbit socket suggest promising result in the human anophthalmic socket.

Purpose: The refracting power of the corneal epithelium is relatively unknown. We measured the keratometric refracting power of the cornea on 15 eyes of patients undergoing photorefractive keratectomy with and without epithelium., Materials: The readings were performed with a videokeratoscope TMS-1. Three readings were averaged to obtain the mean and standard deviations., Results: By removing the epithelium, there was an increase in corneal refracting power. The mean change was +1.19 D (standard deviation +/- 0.36 D) at 1 mm of the center of the cornea. On all patients the optical power of the cornea increased after epithelium removal., Conclusion: The curvature of the Bowman membrane is steeper than the cornea with epithelium. A change in the thickness of the epithelium is related to a modification of the optical power of the cornea. The optical role of the epithelium is to compensate surface irregularities of the Bowman membrane and could explained in part the hyperopia in the first months after excimer laser.

Purpose: The aim of our study was to evaluate a new fluorocarbon (Teflon AF), used as a coating of poly-methylmethacrylate intraocular lenses. Teflon AF can be dissolved in special solvents (liquid fluorocarbons). It is the first amorphous and transparent form of teflon., Materials and Methods: The coating was performed and the surface quality of the teflon-coated lenses was evaluated by scanning electron microscopy. Twenty teflon-coated and 10 uncoated lenses were implanted in rabbit eyes after phacoemulsification. They were compared concerning the presence of iris-lens synechias and the number of deposits on the lens' surfaces. An in vitro static touch model was used to compare endothelial damage produced by the 2 kinds of intraocular lenses. The results from this model were quantitatively analyzed, using the BIOCOM 200 image-processing system., Results: The teflon group had no iris-lens synechias and the control group had 2 extensive synechias. There were significantly fewer deposits on the surfaces of teflon-coated lenses on days 30 and 60 post-operatively (P < 0.0001) than on the control lenses. Teflon-coated lenses produced significantly less endothelial damage than did control lenses (P < 0.0001)., Conclusions: Teflon AF presents an anti-adhesive effect that increases the biocompatibility of polymethylmethacrylate lenses and reduces endothelial damage during their intraocular insertion.

Two cases of bilateral Thygeson's keratitis were examined by in vivo confocal microscopy. In the corneas, fine deposits of highly reflected material appeared immediately below the basal lamina. This is the first time that such morphological features are described in patients with Thygeson's keratitis.

Background: GIAK is a surgical technique developed for the correction of myopia. We evaluated the biocompatibility of a gamma-ray crosslinked poly(ethylene oxide) gel in two critical situations., Materials and Methods: In 3 rabbits, a 5 mm inner diameter annular channel of 1 mm width was delaminated at 80% corneal depth and a sterile gamma-ray crosslinked polyethylene oxide gel was injected in the channel. In cornea 1 (control), the annulus was centered on the corneal apex and the channel was fully filled with gel. In cornea 2, the delamination was purposely decentered and the channel was approximately 1 mm from the limbus at its closest point. In cornea 3, the centered channel was purposely partially filled. After a 6 month follow-up, the rabbits were sacrificed for histology., Results: Histopathology showed the oval channel walls to be irregular and a slight thinning of the epithelium located above the implant but no abnormalities in the stromal thickness. No mononuclear, polynuclear cells or other signs of encapsulation or rejection were found around the polymer in any of the animals. In cornea 3, fibroblasts were found on the lateral sides of the hydrogel globules. No limbal neovascularization was observed over the 6 month period in any of the animals., Conclusions: The injected PEO gel followed intimately the delaminated stromal channel and was well tolerated in the cornea. The fibroblastic reaction found in partially filled channels is caused by the normal wound healing process and not by the hydrogel chemical properties.

Purpose: Our goal was to evaluate a second generation biointegrable keratoprosthetic device (BioKpro II)., Methods: The device consists of a porous transparent PTFE (12 mm diameter) and a soft copolymer structure for the optical system (7 mm diameter). Intraocular pression was evaluated with a Goldmann tonometer on an artificial chamber. A lamellar dissection was carried out 3 mm radially for 360 degrees creating a pocket to accommodate the skirt. The soft optic (42.5 D; 500 microns thick) was positioned through a hole (6 mm in diameter) trephined in the central cornea. A 360 degrees peritomy was performed and conjunctiva was placed in front of the prosthesis, sutured and was opened 15 days post implantation. 14 rabbits were implanted and were allowed to heal for three months., Results: We are able to measure the intraocular pressure by Goldmann tonometer on an artificial chamber. We did not observed epithelialisation on the hydrophilic optical surface (14/14). Aseptic necrosis in direct contact between cornea and the soft optical system was observed when conjunctiva was not effective (4/14). As observed with the first generation devices, conjunctiva or buccal mucosa is needed to avoid local necrosis. In other cases no adverse reactions were observed after implantation., Discussion: The geometry and biomechanical properties of the BioKpro II is closed to that of the human cornea. The junction between the optical and the flange was bound by polymeric interpenetration and prosthesis dislocation was not seen under pressure over 1000 mmHg., Conclusion: Second generation biointegrable keratoprostheses (BioKpro II) can be implanted successfully. Further tests will determine if surface modifications designed to promote epithelial cell attachment on the optical system could prevent ulceration at the junction between the fluorocarbon and the core.

Purpose: Endoscopes for use in ophthalmology can be manufactured in dimensions smaller than 0.89 mm., Materials: Gradient-index lenses that give a higher resolution than fiber bundles can be miniaturized down to 0.35 mm., Results: We used this new endoscope in 6 eyes of 6 patients during anterior segment surgery. Preliminary clinical experience has demonstrated the usefulness and practical application of this new instrument., Conclusion: The clear views the instrument provides of the ciliary sulcus and ciliary body behind the iris make it useful in secondary posterior chamber intraocular lens implantation, retroprosthetic membrane behind keratoprosthesis, Molteno valve, and in endolaser photocoagulation.

We reported three consecutive cases of severe fungal keratitis initially undiagnosed by corneal scrapping. Corneal biopsy showed fungal elements of Paecilomyces lilacinus, Fusarium solani, Scedosporium apiospermum. Most cases of fungal keratitis could be treated successfully if adequate antifungal therapy were started early. Early and accurate diagnosis is of major importance. The results of our cases confirm the superiority of corneal biopsy over corneal scrapping. Corneal biopsy is a procedure of choice in suspected cases of keratomycosis in which corneal scrapings fail.

Radial keratotomy reduces myopia by flattening the central cornea. The role of wound hydration, length and depth of incisions, intraocular pressure and general weakening of the cornea play a part in this process. The relative importance of these factors is not clear. We examined the effect of wound hydration on an 8 incision radial keratotomy (RK) procedure performed on cadaver eyes. The cornea was moistened with balanced salt solution. A mean change of 10 D was achieved after 30 minutes. The corneal dehydration induced by Dextran B was associated with a significant reduction (10 D) in RK induced corneal flattening. It would appear that the radial incision induced keratometric change is a preliminary result of wound hydration. Intraocular pressure within the physiological range had very minimal influence (< 1.5 D) on corneal flattening.

The authors report the course of penetrating keratoplasty (PK) in a series of 3,012 grafts performed at the Hôtel-Dieu de Paris Ophthalmology Department from 1980 to 1991; 2,962 cas (98.5%) could be analysed and were divided into 17 etiologic groups. In the literature, Aphakic Bullous Keratopathy (ABK) and Pseudophakic Bullous Keratopathy (PBK) are usually considered to be the most frequent PK indication. In our series, they came in third place overall with 281 cases (9.5%). Their incidence showed a constant increase over the study period, and they became the most frequent indication in 1991 (21.4% versus 6.8% in 1980). Keratoconus was the most frequent surgical indication with 813 cases (27.6%). This high percentage has been reported by other research groups. We explain our findings by a bias in the choice of corneal recipient candidates due to a tendency of the surgical team to give available donor corneas to patients with statistically higher chances of functional success. We also notice that corneal herpes sequelae, classically the leading cause of PK in the seventies, became the second indication overall and showed a decreasing tendency between 1980 and 1991. Finally, non herpetic leucomas (8.9%), graft failures (8.6%), and Fuchs dystrophy (8.3%) showed a constant PK indication rate throughout the study period.

The authors report a case about relapsing corneal ulceration in a patient with rheumatoid arthritis. Treatment of such perforated and preperforated corneal ulcers is a difficult task. The poor visual outcome of an emergency penetrating keratoplasty leads to the use of other methods (conjunctival flaps, corneal graft, keratopatch, tissue adhesive). This case report stresses the importance of preserving the anatomy of the eye allowing in a record time the performance of corneal graft. The use of immunosuppressive drugs is also discussed because of the existence of a rheumatoid arthritis with eye involvement.

Keratoprosthesis consists in replacing the central cornea with an optical system. The optic requires a support which was usually located in front of or behind the cornea. In our opinion microporous materials can hold the prosthesis in place and prevent melting and leakage. The prosthesis is implanted in a single procedure. The optical core is made of clinical quality PMMA. The core is 5 mm in diameter and 2.5 mm long. To promote tissue stability, 9 mm of a new microporous fluorocarbon (200 microns thick and 80 microns pore size) is used. The material becomes transparent and wettable after implantation in the human cornea as confirmed by experimental investigation. The material of the flange is initially hydrophobic and maintains the depth of the anterior chamber without leakage. We present our results concerning the 10 consecutive cases. The average follow-up is 11 months (range; 6 to 17 months). The surgical indication was 4 cases of corneal burns, 3 cases of pseudopemphigus, 1 trachoma, and 2 cases of corneal edema. Visual acuity was 20/60 (range: 20/400 to 20/30). Anatomic failures occurred in 2 cases in the first two months. We observed one traumatic dislocation of the optic system and one extrusion in the first week after error of manipulation of the polymer. The 5 mm optical diameter of the keratoprosthesis allows a visual field of about 120 degrees.

The refracting power of the corneal epithelium is relatively unknown. We measured the keratometric refracting power of the cornea in two series of 10 fresh bank eyes and on five cat eyes with and without epithelium. The readings were performed at the 2 and 3.6 mm optical zones with an automated keratometer and with a videokeratoscope (TMS-1). The mean change was +1.30 D (0.55-1.85 D) at the 2 mm optical zone and 0.85 D (0.2-1.6 D) at the 3.6 mm optical zone in the first series of 10 eyes. The optical power of the epithelium was most significant within the central cornea. By removing the epithelium there was an increase in corneal refracting power and a change in the power and axis of astigmatism. We discuss the consequences of these findings and how they might affect the outcome of photorefractive keratectomy or other similar keratorefractive procedures.

One case of mucoepidermoid carcinoma of the conjunctiva with intraocular invasion is described. Review of literature retrieve 15 cases of conjunctival localisation of mucoepidermoid carcinoma. These tumors appear to be locally aggressive, they all invade the intraocular or intraorbital structures. They require always a radical surgery with wide excision. Histopathologically, histochemical stains for glycoproteins confirm the diagnosis with admixture of squamous and mucus secreting cells.

To evaluate Gradient-Echo Imaging (GEI) in orbito-ocular pathology, 15 volunteers and 34 patients (40 lesions) were examined with GEA T1 and GEA T2 (0.5 T). Results were compared with SE T1 in all cases, with SE T2 in 20 cases and with other imaging modalities (CT). 30 patients were examined before and after injection of gadolinium. Final diagnosis was obtained by surgery or biopsy in 24 cases or by combined results of imaging and clinical findings in 16 cases. Compared with SE, GEA demonstrated a better visualisation of optic nerve, orbital muscles, choroidal-retinal layer, lens capsule and episclera and a better detection of small lesions. It is very helpful for characterisation of lesions containing hemorrhages or paramagnetic components (melanine, gadolinium) or of vascular nature (angioma). Gadolinium was useful for detection of small lesions or characterisation of a few lesions. Thus GEA seems to be an efficient method for the evaluation of orbito-ocular pathology.

One hundred and twenty-seven eyes of children less than 15 years of age underwent keratoplasty with one to ten years follow-up. The cases were divided into three groups of age, and the results are compared. Graft transparency has a direct correlation with the age of patient and type of corneal disease. Penetrating keratoplasty carries a better surgical and visual prognosis when carried out late in childhood. This is not only the fact of the particular etiologies found in this subgroup of age. When adjusting the results to the both factors age and etiology, we have demonstrated their independent. The visual benefits of corneal transplantation in selected cases in children appear to outweigh the difficulties and problems engendred by this procedure.

In this retrospective study of combined surgery we compared patients who underwent Trabeculectomy (Trab.) + Intracapsular cataract extraction (EIC) +/- Intraocular lens (IOL) with patients who underwent Trabeculectomy + Extracapsular cataract extraction (EEC) +/- IOL. All the patients presented with primary open angle glaucoma with a senile cataract. Each group studied included 20 eyes. After 24 months we confirmed that the mean postoperative intraocular pressure (IOP) showed a decrease of 7.4 mmHg in the first group (EIC + Trab.) and 5.46 mmHg in the second group (EEC + Trab.) of patients. A statistically significant difference was observed between the two groups (p less than 0.05). On the basis of IOP the 1st group showed a success rate of 85% after an average period of 23.55 months (6-43 months). The 2nd group presented a success rate of 90% after an average period of 18.3 months (4-37 months). The mean visual acuity after 24 months improved in the 1st group from 0.10 to 0.50 and in the second group from 0.13 to 0.50. Seventy percent of the eyes recovered a visual acuity greater than or equal to 0.4 in each of the two groups. In both groups of patients, surgery allowed a reduction in the prescription of drugs. We therefore verified that, in the first group, combined surgery allowed us to more effectively control the IOP while achieving a greater improvement in visual acuity. However, it must be stressed that intracapsular cataract extraction is associated with a higher complication rate.

An experimental band keratopathy was produced in rabbits by local injection of egg albumin and vitamin D intoxication. Histological sections have been studied by two methods of analytical microscopy: Electron Probe X rays Microanalysis (EPMA) and Secondary Ion Emission Microanalysis (SIEM). The components and early distribution of calcic precipitations were studied. Calcium, Sulphur and Phosphorus elements were observed. Despite of the highly sensitive techniques used gradual or slope precipitations were not observed any where in the cornea.

Two patients with perforation were treated with an inert vitrous teflon alloplast, expanded polytétrafluoroethylene (E.PTFE). Details of the surgical technique are discussed.

Expanded Polytetrafluoroethylene (E. PTFE) is an inert vitreous teflon alloplast with a high biocompatibility. It is able to be ingrowth by fibrovascular tissue. Very good results are reported in vascular, abdominal and reconstructive surgery and this suggests a possible use in keratoprosthesis. In this purpose, its tolerance and its embedding in the corneal tissues have been studied. Eight perforating keratoplasties are performed in the rabbit with a diameter of 5 mm. A disk of E. PTFE was sutured on the cornea and examined clinically, histologically and by scanning electron microscopy from 1 to 50 days after the operation. Corneal implants are well tolerated but microscopic examination does not show evidence of fibrovascular ingrowth. A full thickness corneal implant seems uneffective in the absence of a conjunctival flap.

The biocompatibility of polytetrafluoroethylene (E. PTFE) keratoprosthetic skirts was studied for periods of observation from 4 to 14 weeks. In a first experimental study, the authors showed that E. PTFE was well tolerated but without fibrovascular ingrowth. In this study, eight perforating keratoplasties were performed and a disk of E. PTFE with a diameter of 4.5 mm was sutured in and covered with a conjunctival flap. The results show that E. PTFE allows fibrovascular ingrowth without a significant foreign body response or encapsulation. Coverage of E. PTFE with conjunctival was essential for fibrovascular ingrowth and to prevent extrusion and rejection.