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J P Adenis

Publications and source records attributed to J P Adenis.

At least 19 recordsLinked to original sources
PubMed2003

[New ceramic materials for use in anophthalmia surgery].

Over the last 20 years eyeball replacement surgery has improved, especially with the widely accepted use of biocolonisable implants. These implants allow long-lasting biointegration, thus improving prosthesis motility and reducing the rate of postoperative exposure. In this article, we review the chemical structure, toxicity data and manufacturing procedures of the three main commercially available materials: aluminium, hydroxyapatite and porous polyethylene.

Aluminum Oxide↗
PubMed2003

Bone formation in hydroxyapatite tricalcium phosphate ceramic implants used in the treatment of the postenucleation socket syndrome.

PURPOSE: To determine the histopathologic changes in coralline hydroxyapatite tricalcium phosphate (HA-TCP) blocks used in the treatment of the postenucleation socket syndrome (PESS). METHODS: Twenty-four patients were treated with HA-TCP blocks placed directly into the orbital fat to correct the PESS. Eight of these patients required partial removal of the material for various reasons between 32 and 371 days after the initial operation. The orbital implants were decalcified and processed for light and electron microscopic examination. RESULTS: Light microscopy demonstrated fibrovascular ingrowth into the pores of the implant in all cases. Osteogenesis was observed in three cases in the periphery of the implant. Ossification occurred in the implants after a mean implantation duration of 276 days versus 67 days in cases without ossification. CONCLUSION: Implants of HA-TCP, a new material used in ophthalmology, demonstrate the presence of fibrovascular ingrowth, reflecting the excellent biointegration of this material.

Adolescent↗
PubMed2001

CT appearances of chronically retained wooden intraorbital foreign bodies.

Identification of wooden intraorbital foreign bodies (WIOFB) is crucial for avoiding severe orbital infection. Despite careful clinical examination, WIOFB are often not recognised. We report the CT findings in chronically retained WIOFB. When not initially diagnosed, WIOFB create a granulomatous inflammatory foreign-body reaction. CT demonstrates the WIOFB as a linear dense structure surrounded by a soft-tissue mass with density similar to that of muscle, corresponding to the foreign-body reaction.

Adult↗
PubMed2001

The failed probing.

The management of failed probing for congenital nasolacrimal duct obstruction is given by a panel of authors. Treatment options examined are repeat probing, inferiorturbinate infracture, closed lacrimal intubation and dacryocystorhinostomy. There is considerable variation as to the timing of these interventional techniques.

Dacryocystorhinostomy↗
PubMed2001

Comparative review of topical ophthalmic antibacterial preparations.

The choice of an antibacterial is based on considerations of pharmacodynamic, pharmacokinetic and bacteriological characteristics, risk of selecting resistant mutants, and cost. In this article we review 16 commercially available ophthalmic antibacterial preparations. Fusidic acid and bacitracin are selective for gram-positive bacteria whereas polymyxin B targets gram-negative species. Aminoglycosides and quinolones are broad spectrum antibacterials. The widespread use of an antibacterial increases risks of selecting resistance to it. Acquired resistance is well documented for fusidic acid and rifamycin, and newly described for quinolones. The bioavailability of an antibacterial agent depends on the target bacterial species, the site of infection and the integrity of the haemato-aqueous barrier. Some agents (fusidic acid, quinolones) penetrate the cornea, passing into the anterior chamber of normal eyes at therapeutic concentrations, whereas others (polymixin B, bacitracin) have no penetrating powers and remain at the surface of the eye. Toxicity is mostly manifested by allergic reactions to excipients or active ingredients in topical antibacterial preparations. A few cases of haematological toxicity have brought suspicion on topical chloramphenicol, but the link has yet to be proven. Erythromycin and polymyxin B are probably okay to use as topical applications in pregnant women and nursing mothers. Costs of treatment must be evaluated as a whole (regimen, drug associations). Prices for a bottle of eyedrops may vary 3-fold. The cheapest drugs include chloramphenicol, polymyxin B and gentamicin, the most expensive being fusidic acid and the quinolones.

Administration, Topical↗
PubMed2001

[Cyclosporin A eyedrops: manufacturing, toxicity, pharmacokinetics and indications in 2000].

INTRODUCTION: Cyclosporin eye-drops allow local immunoregulation without systemic side effects and is an alternate to local steroids. In this article we review specific problems of product setup and clinical studies published over the past 20 years. PRODUCT SETUP: The main problems in eye-drop preparation are sterility, pH, particles, and its lipophilic properties. Numerous excipients have been tested including oil solvents, alphacyclodextrin, collagen shields, liposomes, polyester nanocapsules, but documentation on stability of the molecule is inadequate. TOXICITY: Epithelial toxicity is well known and is probably mainly due to the excipient. No endothelial toxicity has been described in vivo. Repeated doses lead to uveal reactions in animals, which could limit the indications for intraocular diseases. PHARMACOKINETICS: Bioavailability is mainly limited by the lipophilic properties. Oil excipients, the most widely used, lead to good corneal penetration but low intraocular concentrations. Cyclosporin bioavailability is improved when using hydrophilic excipients. INDICATIONS: Every ocular surface disease that involves cytokines is a potential indication for cyclosporine eyedrops: keratoconjunctivitis sicca, vernal keratitis, adjuvant therapy of filtering surgery, stromal herpes keratitis, immunity limbal keratitis, and Thygeson's keratitis. There is biological evidence of efficacy, and encouraging results from many studies, yet few have tested a large number of patients. A large multicenter study on dry eye is currently in progress.

Biological Availability↗
PubMed2001

[Evisceration using the Russian doll or the parachute technique].

The authors describe two new techniques of evisceration after resection of the corneal epithelium and limbus with a conservative approach of the posterior lamella of the cornea and anterior sclera after a 360 degrees dissection of the sclera behind the insertion of the oculomotor recti muscles, and with a conservative approach of the recti oculomotor muscles. The technique is called "Parachute" when the posterior sclera is removed and "Russian Doll" when the posterior sclera is not removed and placed behind the orbital implant. The implant is then introduced with "bird cage" forceps. The indications of the technique are those of evisceration when the size of the remaining globe is at least one-third of the volume of a normal eye. The main advantage is to provide safely a large volume for the implant in order to prevent post enucleation socket syndrome.

Eye Evisceration↗
PubMed2000

The bioceramic orbital implant: a new generation of porous implants.

PURPOSE: The authors describe a new generation of porous orbital implant made of aluminum oxide (Al2O3) and compare it with the hydroxyapatite orbital implants (Bio-Eye and FCI hydroxyapatite). METHODS: The authors examined the new implant macroscopically, with chemical analysis and microscopically with scanning electron microscopy. Animal implantation studies were performed using six adult male New Zealand albino rabbits. Implant vascularization was evaluated by means of magnetic resonance imaging and histopathologic sectioning. RESULTS: The Bioceramic orbital implant was found to have very uniform pore structure with an average pore size of 500 microm. The implant was 99.9% aluminum oxide on x-ray diffraction. Magnetic resonance imaging in vivo vascularization studies demonstrated enhancement of the implant to its center by 4 weeks after implantation in the rabbit. Histopathologically, fibrovascularization occurred uniformly throughout the implant and was noted by 4 weeks. CONCLUSIONS: The Bioceramic orbital implant represents a new porous orbital implant that has a very regular and extensive interconnected pore system, is as biocompatible as hydroxyapatite, is easy to manufacture, structurally strong, and free of contaminants. It is manufactured with no disruption to marine life ecosystems as may occur in the harvesting of coral for other orbital implants. It is less expensive than currently available hydroxyapatite implants and was approved by the U.S. Food and Drug Administration in April 2000.

Aluminum Oxide↗
PubMed1999

HLA-G and classical HLA class I transcripts in various components of the adult human eye.

HLA-G transcripts have previously been detected in the ocular cell line HS738, in foetal eyes and in global ocular extract. Using RT-PCR and hybridization, we searched for HLA-G and classical HLA class I transcripts in the corneas of eye donors (n = 6) and in various components of eyes collected at time of surgery: lens (n = 3), iris (n = 2), vitreous body (n = 2) and retina (n = 2). Whereas HLA class I mRNA was abundant in the ocular tissues of all donors, we could not find HLA-G transcript in any ocular tissues obtained from subjects in vivo. The absence of HLA-G in adult eye cornea limits its interest as a possible target in corneal transplantation. Classical HLA class I transcripts were abundant in the cornea and other components of the eye. These results highlight the role of classical HLA class I antigen in eye immunity and corneal transplantation.

Cornea↗
PubMed1999

Treatment of the postenucleation socket syndrome with a new hydroxyapatite tricalcium phosphate ceramic implant.

PURPOSE: Surgical correction of the postenucleation socket syndrome (PESS) is challenging. Various biomaterials are used for reconstruction of the anophthalmic orbit, often with unsatisfactory long-term results. Implants have been placed between the periorbital and the orbital floor. The authors describe a new material composed of hydroxyapatite tricalcium phosphate (HA-TCP) in the form of ceramic blocks, to be placed into the orbital fat as a new surgical site. METHODS: Ten patients with PESS underwent surgery to compensate the volume deficit of the anophthalmic orbit. Blocks of HA-TCP were created by fragmentation of a larger piece, tailored as needed, and implanted in the orbital fat. The patients were monitored regularly with clinical and radiologic examinations to evaluate the behavior of the implants. RESULTS: The volume of the HA-TCP was measured in 5 cases (mean, 2.95 +/- 1.08 ml). A significant reduction of enophthalmos was obtained: mean Hertel exophthalmometry measured 12.7 +/- 2.5 mm preoperatively and 14 +/- 2.4 mm postoperatively (p < 0.05). The average prosthesis volume was significantly reduced in the cases measured: 2.7 ml +/- 0.94 ml preoperatively and 1.8 +/- 0.7 ml postoperatively (p < 0.02). There was a negative correlation between the HA-TCP implant volume and postoperative prosthesis volume (correlation coefficient = -0.925; p < 0.05). According to photographic evaluation, correction of the enophthalmos and of the superior sulcus depression were obtained in 70% and 90% of cases, respectively. Magnetic resonance imaging seems to demonstrate that the blocks become well integrated into the surrounding orbital tissue. CONCLUSION: The HA-TCP blocks correct some anomalies of PESS. Placement of the blocks directly into the orbital fat is a promising alternative to the traditional subperiosteal location.

Adolescent↗
PubMed1999

[Intra-orbital decompression of the optic nerve by opening the peri-optic meninges in the treatment of severe optic neuropathies complicating benign intracranial hypertension].

Papilledema from benign intracranial hypertension can cause severe loss of visual acuity and visual field, with an optic neuropathy. We report a study of 5 patients with benign intracranial hypertension, and severe visual loss (visual field loss and visual acuity reduced to 1/10 or less) not improved by medical therapy (acetazolamide). We performed unilateral orbital decompression of the optic nerve sheath. No major operative complication was noted. Follow-up ranged from 11 months to 23 months, with an average of sixteen months. Visual function improvement was noted within 3 months after operation in 4 patients (for 2 eyes on the surgical side improvement of 2/10 and 5/10, for 3 eyes on the opposite surgical side average improvement of 4.6/10). The other patient showed improvement, but no significant. Optic nerve sheath decompression in benign intracranial hypertension seems to be a safe procedure and a therapeutic option in the management of raised intracranial pressure complicated by optic neuropathy with severe visual loss.

Acetazolamide↗
PubMed1998

[Biocompatibility of a porous alumina orbital implant. Preliminary results of an animal experiment].

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.

Aluminum Oxide↗
PubMed1997

Local antimicrobial prophylaxis in cataract surgery: recent controversies and clinical guidelines.

The best prevention of endophthamitis is the use of strict surgical hygiene. Supplementing the irrigating solution with aminoglycosides and/or vancomycin is a rational, convenient and cost effective method of antimicrobial prophylaxis. However emerging resistance to vancomycin entails restrictions to its daily use. In conclusion, two options are possible: limit the use of prophylaxis in the irrigating solution to only those patients at high risk of injection, or use topical and general antibioprophylaxis with low cost drugs.

Anti-Bacterial Agents↗
PubMed1997

[Treatment with cyclosporin A, with low doses, in high-risk penetrating keratoplasties. A bi-centric study of 90 cases].

PURPOSE: Evaluation of cyclosporin-A in prevention of immune reaction in high-risk penetrating keratoplasties. MATERIAL AND METHODS: Cyclosporin A was given to 45 corneal allograft recipients, 5 mg/kg/j (cyclosporinemy between 100 and 150 ng/l), for three months following surgery. 45 controls have undergone penetrating keratoplasty during the same period. Mean follow-up was respectively 431 days and 402 days. Survival was analysed according to Kaplan-Meier's method, and then using Cox model. RESULTS: The significant predictive factors were the number of neovascularized quadrants, and the graft diameter. No significant effect of cyclosporin is evidenced. Side effects are marginal. CONCLUSION: Three hypothesis may explain the absence of prognosis improvement in the Cyclosporin A treated group: insufficient dose or duration of treatment, individual risk factors that prevents correct pairing, or corneal-specific immunological mechanisms.

Cyclosporine↗