PubMed Health⌕ Search

Biomedical subjects

T Bourcier

Publications and source records attributed to T Bourcier.

At least 19 recordsLinked to original sources
PubMed2006

Effects of topical anaesthetics and fluorescein on the real-time PCR used for the diagnosis of Herpesviruses and Acanthamoeba keratitis.

BACKGROUND: The early microbiological diagnosis of corneal infections may prevent the condition from worsening. AIM: To study the potential interferences of oxybuprocain and fluorescein solutions used by ophthalmologists on the performances of the real-time polymerase chain reaction (PCR) carried out as routine test for diagnosis of keratitis. METHODS: Quantified suspensions of Herpes simplex virus (HSV1), Varicella zoster virus (VZV), Cytomegalovirus (CMV) and Acanthamoeba with and without oxybuprocain or fluorescein added before DNA extraction were tested by real-time PCR. RESULTS: The capacities of the real-time PCR to detect HSV, VZV, CMV and Acanthamoeba were reduced by oxybuprocain and fluorescein. Both products diluted to 1/16 reduced the PCR detection capacities for more than 2 logs (DNA copies/sample). CONCLUSIONS: The simultaneous introduction of fluorescein or topical anaesthetics into the tubes containing the specimens to be tested by PCR may lead to false negative results. Because corneal specimens for microbiological diagnosis of keratitis are obtained after topical administration of anaesthetics and corneal staining with fluorescein, ophthalmologists should be aware to rinse the eye surface intensively with appropriate eye solutions to minimise the risks of misdiagnosis.

Acanthamoeba↗
PubMed2006

[Diagnosis of Acanthamoeba spp. keratitis with PCR].

AIM: Evaluation of a PCR assay as a diagnostic tool for detection of Acanthamoeba spp. in patients presenting infectious keratitis. METHODS: Between August 2001 and November 2002, 342 clinical specimens consisting in corneal scrapings from 334 patients were tested for Acanthamoeba using direct microscopy, culture, and PCR. A fragment of Acanthamoeba 18S rRNA gene was amplified using a set of primers referred to as Nelson's primers. RESULTS: A diagnosis of Acanthamoeba keratitis was considered for nine patients. Amoeba growth in culture was unfruitful for all of these cases. Eight patients had corneal scrapings that tested positive with PCR; in two cases direct microscopy observations confirmed PCR results. For one patient, a negative PCR result was obtained; however, a second corneal sample and cysts staining on May-Grünwald-Giemsa were positive. A false-positive PCR result was noted related to another amebic genus. A risk factor was found in all Acanthamoeba keratitis cases (contact lenses, trauma). Topical treatment was successful, and keratoplasty was necessary afterwards for optical rehabilitation in five patients. CONCLUSION: This study suggests that PCR is a sensitive diagnostic tool, superior to conventional techniques for detecting Acanthamoeba in corneal lesions.

Acanthamoeba↗
PubMed2004

Tissue crossmatch before corneal transplantation.

AIM: To investigate the influence of anticorneal antibodies on the outcome of transplantation in recipients before penetrating keratoplasty. METHODS: 100 consecutive penetrating keratoplasties performed between July 1995 and June 1996 were included in this study. Donor corneoscleral rim cryosections were incubated with recipient serum. Fixation of recipient IgM on donor corneas was revealed with a polyclonal anti-human mu-chain antibody. The mean follow up time was 61 months. Five years after transplantation, 63% of patients were available for follow up. During the follow up period, 15% of keratoplasties failed because of irreversible rejection. RESULTS: Anti-donor stromal lamellae IgM were found in 14 recipients. Anti-donor keratocyte IgM were present in 28 recipients. Dilution of recipient serum (up to 1/800) did not modify the results of positive crossmatch assays. Crossmatch assays performed with positive recipient sera and negative donor corneoscleral rims were negative. No significant influence of IgM crossmatch results on graft survival and rejection-free graft survival was found. CONCLUSION: Donor specific anticorneal stroma IgM were found in 28% of recipients before transplantation. This pre-immunisation was not associated with a higher risk of transplantation rejection.

Adult↗
PubMed2003

Bacterial keratitis: predisposing factors, clinical and microbiological review of 300 cases.

AIM: To identify predisposing factors and to define clinical and microbiological characteristics of bacterial keratitis in current practice. METHODS: A retrospective analysis of the hospital records of patients presenting with bacterial keratitis and treated at the Quinze-Vingts National Center of Ophthalmology, Paris, France, was performed during a 20 month period. A bacterial keratitis was defined as a suppurative corneal infiltrate and overlying epithelial defect associated with presence of bacteria on corneal scraping and/or that was cured with antibiotic therapy. Risk factors, clinical and microbiological data were collected. RESULTS: 300 cases (291 patients) of presumed bacterial keratitis were included. Potential predisposing factors, usually multiple, were identified in 90.6% of cases. Contact lens wear was the main risk factor (50.3%). Trauma or a history of keratopathy was found in 15% and 21% of cases, respectively. An organism was identified in 201 eyes (68%). 83% of the infections involved Gram positive bacteria, 17% involved Gram negative bacteria, and 2% were polymicrobial. Gram negative bacteria were associated with severe anterior chamber inflammation (p=0.004), as well as greater surface of infiltrates (p=0.01). 99% of ulcers resolved with treatment, but only 60% of patients had visual acuity better than the level at admission, and 5% had very poor visual outcome. CONCLUSIONS: Contact lens wear is the most important risk factor. Most community acquired bacterial ulcers resolve with appropriate treatment.

Adolescent↗
PubMed2003

[A new case of Susac syndrome and a review of the literature].

We report a single case of Susac syndrome (microangiopathy of the brain, retina, and cochlea). A 26-year-old woman developed branch retinal artery occlusion in the right eye, associated with bilateral hearing loss that mostly involved low frequencies. MRI of the brain revealed small multifocal hyperintensities in the white matter of the cerebrum on T2-weighted images with gadolium enhancement. The treatment consisted of anticoagulation and antiplatelet drugs. Seventy-one cases of Susac syndrome have been reported in the literature. The Susac syndrome is more frequent in females and its etiology remains unknown. However, immune inflammatory disorders, vasospastic phenomena, and coagulopathy could be involved in its pathophysiology. Treatment options are not standardized, ranging from antithrombotic drugs to immunomodulatory therapy. The course of the disease is self-limited after an initial fluctuating active phase. The prognosis of Susac syndrome is good in most cases.

Adult↗
PubMed2003

[Lasik correction of compound myopic astigmatism with positive versus negative cylinder ablations].

PURPOSE: To compare the predictability, efficacy, and safety of two methods of Lasik correction of compound myopic astigmatism: positive cylinder ablation versus negative cylinder ablation. METHODS: Twenty nine eyes of 19 patients were retrospectively analyzed. They had undergone Hansatome or ALK-e flap keratectomy, and a Technolas Keracor 217c laser ablation. Group 1 (14 eyes) was corrected with the positive cylinder program, group 2 (15 eyes) with the negative cylinder program. Spherical equivalent (SE), cylinder, vector analysis, and best corrected and uncorrected visual acuities (BCVA, UVA) were compared in the two groups. Minimum follow-up was 6 months. RESULTS: The preoperative mean SEs for groups 1 and 2 were, respectively, - 7.09+/-3.36 D and - 8.05+/-2.27 D (NS). Mean cylinders were 1.73+/-0.88 (group 1) and +/-0.74 (group 2) D. Visual acuities were not statistically different in the two groups. Postoperative mean SEs were, respectively, - 0.57+/-1.58 D and - 0.68+/-0.88 D. Mean cylinder was, respectively, 0.57 +/- 0.54 D and 0.7 +/- 0.46 D in groups 1 and 2. Astigmatism induced by surgery, calculated by vector analyses was, respectively, 1.36 +/- 0.66 D and 1.54 +/- 0.56 D. Percentages of UVA above 20/25 were, respectively, 50% and 35%. None of those differences was statistically significant. One eye lost one line of BCVA. CONCLUSION: The positive cylinder ablation method makes a larger optical zone of ablation possible with the same central deepness of ablation. We found that the predictability, efficacy, and safety of this technique compares well with the negative cylinder ablation in compound myopic astigmatism.

Astigmatism↗
PubMed2003

[Long-term refractive and topographic changes after penetrating keratoplasty].

PURPOSE: To analyze long-term refractive and videokeratoscopic changes after penetrating keratoplasty. PATIENTS AND METHODS: Forty eyes of 40 patients (26 keratoconus) with a clear corneal graft and no other ocular disease were examined after all sutures were removed, respectively at 22.0+/-7.3 months and 50.5+/-13.6 months after keratoplasty. All of the eyes were examined using videokeratography (EyeSys 2000) and ultrasonic pachymetry. Changes in subjective refraction, best spectacle-corrected visual acuity (LogMAR units), topography, and central corneal thickness between both exams were recorded. RESULTS: Visual acuity increased by an average of 0.41 lines +/-0.24 (p<0.001) between both exams, whereas no significant change in refractive astigmatism and videokeratoscopy (i.e., power, pattern, and indices) was observed. Central corneal thickness significantly increased from 545+/-36 micro m to 574+/-40 micro m (p<0.001). Change in best spectacle-corrected visual acuity significantly correlated with delay between the exams (r(s)=+0.34, p=0.03), whereas change in refractive astigmatism, topographic indices, and topographic patterns did not significantly correlate with delay. CONCLUSION: After penetrating keratoplasty, visual acuity improves long after surgery, whereas refraction and corneal surface regularity show no significant modification. This improvement in visual acuity, not explained by current techniques, may be due to an increase in graft transparency.

Adolescent↗
PubMed2003

[Combining artificial tears---are they always synergistic?].

We report one case of thick, sticky, palpebral and conjunctival deposits following administration of artificial tears in a patient treated for dry eye syndrome. Experimental data confirmed clinical observation. The association of Refresh artificial tears and Dacudoses or Dacryoserum used as a washing solution should be avoided.

Borates↗
PubMed2003

[Treatment of the sequelae of ocular burns using limbal transplantation].

PURPOSE: To report the results of limbal transplantation in patients with severe ocular burns and limbal stem cell deficiency. PATIENTS AND METHODS: This series includes six autografts (unilateral ocular burns) and five allografts (bilateral ocular burns) performed in ten eyes of ten males with an average age of 43 years. The origin of the ocular burn was chemical in eight cases and thermal in the remaining two cases. The average time between the initial trauma and limbal transplantation was 79 months. The average size of limbal grafts was 190 degrees (range: 80-20 degrees for autografts and 120-360 degrees for allografts). Patients with allografts received oral cyclosporine in three cases, topical cyclosporine in one case, and intravenous methylprednisolone in one case. Eight patients underwent penetrating keratoplasty an average of 11 months after limbal transplantation (range: 5-24 months). RESULTS: The average follow-up time was 36 months (range: 7-77 months). The overall success rate of limbal transplantation (ocular surface improvement) was 73% (8/11). The success rate of penetrating keratoplasty was 63% (5/8). The average initial visual acuity was 0.4/10 and the average final visual acuity was 1.6/10. Visual acuity improved by two lines or more in seven cases. DISCUSSION: Limbal transplantation is a useful surgical technique in patients with severe ocular burns. However, results remain insufficient and new techniques such as limbal stem cell culture and transplantation are needed to improve the visual prognosis of these patients.

Adult↗