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O Touzeau

Publications and source records attributed to O Touzeau.

At least 19 recordsLinked to original sources
PubMed2006

[Advantages of the autorefractometer and the Orbscan for measuring pupil diameter].

PURPOSE: We compared pupil size measurements obtained with the Orbscan and autorefractometer to the Colvard Infrared pupillometer in order to determine their respective clinical advantages. MATERIAL AND METHODS: We prospectively measured the pupil diameter in 94 eyes of 47 normal patients using the Colvard device, the Nikon NKR 8000 autorefractometer, and the Orbscan device. For each device, two successive measurements were taken to determine its reproducibility. We also studied the relationship with the contralateral eye (i.e., difference and correlation). The measurements obtained with the different devices in different light intensities were compared and studied using regression analysis. RESULTS: Pupil diameter measured using the Orbscan had the highest reproducibility (mean difference between the two successive measurements: 3.8% or 0.15mm) and showed the smallest difference between the two eyes (5.0% or 0.19mm) and the strongest correlation with the contralateral eye (r=0.93; p<0.001). Scotopic Colvard measurements and autorefractometer measurements with low light settings were not significantly different (5.86mm versus 5.86mm; p=0.48). Autorefractometer measurements with low light settings showed the strongest correlation with the scotopic Colvard measurements (r=0.84; p<0.001). The Orbscan measurements were less correlated with the scotopic or photopic Colvard measurements (r=0.73; p<0.001 and r=0.51; p=0.003, respectively). For the Colvard pupillometer, the correlation between photopic measurements and scotopic measurements was also poor (r=0.51; p<0.001). CONCLUSION: Pupil size measurements with the autorefractometer may be advantageous before refractive surgery. Measuring pupil size in photopic conditions, as with the Orbscan, cannot screen people with large pupils in mesopic conditions.

Adolescent↗
PubMed2005

[Prevention of proliferative vitreoretinopathy using 5-FU heparin: clinical tolerance and efficacy].

PURPOSE: To study the safety and efficacy of adjuvant combination therapy using 5-fluorouracil and heparin for prevention of proliferative vitreoretinopathy (PVR) during vitrectomy for retinal detachment surgery. METHODS: Two consecutive groups of 30 eyes with a rhegmatogenous retinal detachment (grade C1 or more) were prospectively compared. In the study group, 5-FU and heparin were administrated in the intraoperative infusion. Clinical safety and the efficacy were regularly studied over 1 year. RESULTS: In the 5-FU heparin therapy group, keratitis was more frequently observed the 1st day after surgery (p = 0.005), but not after 1 week (p = 0.54). However, conjunctival hyperemia was more severe after 1 and 7 days (p = 0.04). In both groups, no differences were found concerning intraocular pressure, postoperative hemorrhage or inflammatory reaction (flare) of the anterior chamber and the aspect of the eyelids (p > or = 0.14). The number of reoperations resulting from PVR, after 1 month and 1 year, was not significantly different between the two groups (p > or = 0.3). The reattachment rate and visual acuity (BSCVA) were not statistically different after 1 year (p > or = 0.12). CONCLUSION: Adjuvant combination therapy using 5-FU and heparin seems to be safe. However, its efficacy needs to be demonstrated by larger studies including eyes presenting a lower grade of PVR (grade B).

Drug Therapy, Combination↗
PubMed2005

[Ocular biometry using Orbscan].

Orbscan is a recent optical device that combines the Placido disk of the videokeratoscope and a scanning slit. The scanning slit measures the elevation of both the corneal surface (anterior and posterior) and the anterior iris-lens surface. Biometric measures of the anterior segment such as corneal thickness, anterior chamber depth, corneal diameter, and iridocorneal angle are obtained using spatial coordinates of various ocular surfaces. Orbscan is not only a corneal topograph but a versatile device capable of measuring the biometry of the anterior segment of the eye.

Biometry↗
PubMed2005

[Crystalline lens biometry using A-scan ultrasound and the Orbscan device].

PURPOSE: To analyze the lens biometry obtained by Orbscan and A-scan ultrasound in normal eyes. MATERIAL: and methods: The lens thickness obtained by A-scan ultrasound and the anterior curvature of the crystalline lens obtained by Orbscan were prospectively recorded in 280 normal eyes (including eyes with ametropia) of 140 patients (10-95 years of age). The correlation of lens biometry with the contralateral measure, patient age and sex, subjective refraction, and other ocular biometric parameters (anterior chamber depth, iridocorneal angle, corneal diameter, central pachymetry, pupil, corneal radii of curvature, and posterior segment length) was assessed. RESULTS: The lens anterior curvature showed no significant correlation in particular with the subjective spherical equivalent; however, the quality of this measure was poor: the reproducibility of the lens anterior curvature was low (the average difference between two successive Orbscan measurements was 14.4%). The correlation with the contralateral eye was poor (rs=0.55; p<0.001 versus rs=0.97; p<0.001 for lens thickness). Lens thickness showed the strongest correlation with the patient's age (rs=0.82; p<0.001); it increased by 0.26 mm per decade. Lens thickness correlated with anterior chamber depth (rs=-0.72; p<0.001) and iridocorneal angle (rs=-0.65; p<0.001). The last two parameters also correlated with age (rs=-0.68; p<0.001 and rs=-0.62; p<0.001, respectively). Anterior chamber depth and iridocorneal angle decreased by -0.21 mm and -1.7 degrees , respectively, per decade. CONCLUSION: Lens thickness is mainly influenced by age and correlates with the anterior chamber depth and the iridocorneal angle. The influence of aging on anterior segment biometry essentially consists in an increase in lens volume.

Adolescent↗
PubMed2004

[Biometric study of acute-angle-closure glaucoma using Orbscan and echography].

PURPOSE: To study acute-angle-closure glaucoma (AACG) biometry using Orbscan and echography. MATERIAL AND METHODS: We prospectively studied 200 normal eyes of 100 patients (including eyes with ametropia), 50 eyes of 25 patients before peripherial YAG laser iridotomy, 25 phakic eyes of 25 patients with a history of acute-angle-closure glaucoma (AACG) in the fellow eye. Both plane and polynomial modes of reconstruction of the iridocorneal angle measurement were analyzed. Biometric measurements of the three groups were compared. Biometric measurements (i.e., iridocorneal angle, anterior chamber depth, axial length, and lens thickness) and subjective spherical equivalent were correlated with the etiological classification. RESULTS: Age, sex, iridocorneal angle, anterior chamber depth, lens thickness, axial length and subjective spherical equivalent were significantly different in the three groups (p<0.002). The polynomial iridocorneal angle measurement was 43.4 degrees in the normal group, 36.5 degrees in the iridotomy group, and 28.4 degrees in the AACG group (p<0.001). Iridocorneal angle measurement correlated with the other biometric measurements (rs>0.51; p<0.001) and with the etiological classification (rs< or =0.68; p<0.001). The anterior chamber depth measurement obtained by Orbscan or echography was the best parameter for predicting ACCG (rs=0.77; p<0.001). CONCLUSION: The anterior chamber depth and polynimial iridocorneal angle obtained using the Orbscan device appears to be useful in predicting acute-angle-closure glaucoma.

Acute Disease↗
PubMed2004

[The relationship between keratoconus and axial myopia].

PURPOSE: To study the relationship between keratoconus and axial myopia. METHODS: We prospectively studied refraction and ocular biometry in 100 consecutive keratoconus eyes, and 100 emmetropic eyes. Biometric data (including posterior segment length) were obtained by A-scan ultrasound, Orbscan, and ultrasonic pachymetry. Biometric measurements were compared in both groups. RESULTS: Anterior chamber depth, posterior segment length and axial length were significantly different between the two groups (p<0.001). Axial length was significantly greater in the keratoconus group than in the emmetropic group (23.97 mm versus 23.21 mm, p<0.001). Posterior segment length was significantly greater in the keratoconus group than in the emmetropic group (16.54 mm versus 15.99 mm, p<0.001). In the keratoconus group, the posterior segment length and the subjective spherical equivalent were significantly correlated (rs=-0.45, p<0.001). CONCLUSION: The increase in posterior segment length in the keratoconus group and the correlation between posterior segment length and spherical equivalent in the keratoconus group suggest a statistical relationship between keratoconus and axial myopia.

Adolescent↗
PubMed2004

[Anterior segment of the eye and diabetes mellitus].

OBJECTIVE: To study the damage to the anterior segment of the eye during mellitus diabetes. METHODS: We prospectively studied the anterior segment of the eye in 200 diabetic patients and 200 patients with no history of diabetes (control group). Parameters included the corneal curvature radius, corneal thickness, central corneal sensitivity (Cochet Bonnet esthesiometer), pupil diameter before and after dilation using tropicamide and phenylephrine eye drops, delay for maximal pupil dilation, lens transparency, and intraocular pressure. The damage to the anterior segment was compared in both groups and was correlated with the parameters of diabetes (type, duration, and equilibration), retinopathy grade, and peripheral neuropathy. RESULTS: Corneal geometry (i.e., curvature radius and thickness) and intraocular pressure did not correlate with diabetes. Cataract was significantly influenced by diabetes (p<0.001). The duration needed to obtain pharmacological maximal mydriasis significantly correlated with iris color (rs=0.47, p<0.001), patient age (rs=0.28, p<0.001) and diabetes (rs=0.25, p<0.001). Dilation was significantly longer in the diabetic patient than in those of the control group (36.5 min vs 30.7 min, p<0.001). Corneal sensitivity significantly correlated with age (rs=0.48, p<0.001) and diabetes (rs=0.53, p<0.001). Corneal sensitivity was decreased in the diabetic group (5.42 vs 5.94, p<0.001) and it correlated with retinopathy grade (rs=0.47, p<0.001) and with peripheral neuropathy (rs=0.15, p<0.001). Sensitivity and specificity of hypoesthesia in detecting peripheral neuropathy were 67.4% and 49.4%, respectively. Among the parameters of diabetes, duration of progression showed the strongest correlation with damage to anterior segment (rs > or = 0.25, p<0.001). CONCLUSION: Diabetes influences lens transparency, pharmacological pupil dilatation and corneal sensitivity. In spite of the unspecific character of the damage and the subjectivity of the measurement, corneal sensitivity is an interesting parameter to take into consideration among diabetic patients.

Anterior Eye Segment↗
PubMed2004

[Pharmacological adjuvants for surgical treatment of proliferative vitreoretinopathy].

Proliferative vitreoretinopathy (PVR) is the major cause of retinal detachment surgery failure. Many adjuvants were studied in vitro and on animals, some were studied on humans. Daunomycin seems to reduce PVR recidivism. 5-FU and steroids are nontoxic but their efficacy is not clear. Heparin reduced postoperative inflammation and seems to reduce PVR recidivism when associated with 5-FU. Associating heparin and steroids seems to reduce PVR in some groups of patients (aphakic, anterior PVR). Colchicine and retinoic acid per os are ineffective, silicone oil is effective as an internal tamponade but not as an adjuvant of PVR. Currently, no molecule has proven efficacy as an adjunctive treatment of PVR.

Chemotherapy, Adjuvant↗
PubMed2004

[A study of pupil dilation using the Mydriasert ophthalmic insert].

PURPOSE: To evaluate the tolerance and efficiency of the Mydriasert(R) ophthalmic insert on pupil dilation. METHOD: Two pharmaceutical forms of a combination of tropicamide and phenylephrine (HCl) were compared on both eyes of 80 patients. For each patient, one Mydriasert insert (Ioltech) was placed in the lower conjunctival sac of the eye. Dilation of the control eye was obtained using 0.5% tropicamide eye drops and 10% phenylephrine eye drops (Novartis Ophthalmics), which were instilled with three frequency regimens (5, 10 or 15 min). The pupil diameter was regularly measured until the maximal mydriasis had occurred. RESULTS: Both subjective and objective tolerance of the insert was excellent. The size of the maximal mydriasis obtained when using the insert was significantly greater than that obtained when using the eye drops, regardless of the frequency of the instillation (p < 0.04). The difference in maximal pupil diameter ranged from +0.16 mm to +0.38 mm. Mydriasis kinetics was slower with the insert. The time necessary to obtain a maximal mydriasis was 47.3 min when the insert was used, whereas it was in the range of 31.4 to 38.5 minutes with the eye drops (p < 0.001). As far as pupil diameter is concerned, the superiority of the insert compared to the eye drops became observable only about 45 min after the insert had been placed in the eye. The relative efficacy of the insert compared to the eye drops did not correlate with patient features (p > or = 0.06). CONCLUSION: Despite the small quantity of drug delivered by the insert, Mydriasert allows a much greater mydriasis compared to that usually obtained when the eye drops were used. However, a longer time lapse is necessary for this to occur.

Adolescent↗
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

[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

[Correlation between refraction and ocular biometry].

PURPOSE: To study the correlation between subjective refraction and biometry obtained by Orbscan and echography in normal eyes. To compare biometric parameters with the subjective spherical equivalent. MATERIAL AND METHODS: Subjective refraction, biometric parameters using Orbscan, and echography were recorded in 190 normal eyes (including eyes with ametropia) of 95 patients. Biometric parameters (i.e., corneal diameter, anterior chamber depth, central pachymetry, iridocorneal angle, corneal and lens radii of curvature, and axial length of the eye) were compared in different refractive groups and were correlated with the subjective refraction. RESULTS: Corneal biometric parameters did not correlate with the subjective spherical equivalent and showed no differences between the refractive groups except for the central pachymetry. In the high myopic group (<-6D), the central cornea was significantly thinner (531 micro m versus 549 micro m, p=0.016). The correlation between corneal radius and axial length was strong in emmetropic eyes (r(s)=0.63, p<0.001) and poor but significant in ametropic eyes (r(s)=0.28, p=0.002). Axial length, anterior chamber depth, and iridocorneal angle showed significant differences between the refractive groups (p<0.001) and correlated with the subjective spherical equivalent (r(s[[/INF=0.44, p<0.001). Subjective spherical equivalent showed the strongest correlation with the axial length (rs)=0.82, p<0.001). Subjective spherical equivalent, central corneal thickness, axial length, anterior chamber depth, and anterior corneal radius showed a strong correlation between both eyes (rs[[/INF=0.94, p<0.001). CONCLUSION: Biometric characteristics of the eye (excluding cornea characteristics) vary with subjective spherical equivalent. Axial length presents the strongest correlation with the subjective spherical equivalent and correlates with the other ocular biometric parameters. Axial length plays a major role in the ocular biometry and refraction.

Adult↗
PubMed2003

[Incidence and factors influencing glaucoma after penetrating keratoplasty].

PURPOSE: To determine the incidence and factors influencing glaucoma following penetrating keratoplasty. MATERIAL AND METHOD: We prospectively studied 440 consecutive patients undergoing penetrating keratoplasty over a period of 5 years, with an average follow-up of 2 years. High intraocular pressure was defined as IOP over 20 mmHg measured by Goldmann applanation for at least 1 week or if a patient required topical treatment for at least 1 week. Before surgery, 18.7% of the patients presented with glaucoma or high intraocular pressure; 44.9% received a graft for a bullous keratopathy condition, 25.6% had keratoconus, 31.5% received an anterior chamber lens, and 48.5% were phakic. RESULTS: After surgery, 42.2% of the patients had ocular pressure at 20 mmHg or more and required treatment for high ocular pressure. The increase in intraocular pressure appeared after an average delay of 3.3 +/- 4.7 months. The frequency of the increase in intraocular pressure was 54.3% for the bullous keratopathy patients, 26.6% for the keratoconus patients (p<0.001). At the end of the second year, the graft survival was 82.1% in absence of glaucoma, whereas it was 71.5% in cases of glaucoma after keratoplasty. Between all parameters that we studied, high intraocular pressure before surgery, etiology, the status, and receiver age over 60 years were the main factors influencing high intraocular pressure after keratoplasty. Intraocular pressure was correlated with the decrease in endothelial cell density and was at the origin of graft failure. Intraocular pressure correlated with the Best Spectacle Corrected Visual Acuity (BSCVA) by its effect on endothelial cell density and optic nerve destruction. CONCLUSION: The increase in intraocular pressure is a real and serious complication of keratoplasty. Its physiopathology is very complex. Better knowledge of risk factors can be useful in controlling it.

Adolescent↗
PubMed2003

[Calculating the mean visual acuity and the change in visual acuity with a decimal acuity chart].

The decimal visual acuity chart is not easy to use for statistical analysis and requires a transformation into LogMAR units (decimal logarithm of the Minimum Angle Resolution). In contrast to the decimal chart, the logarithmic chart has an arithmetic progression and a constant interval between lines. The LogMAR chart makes statistical analysis of visual acuity easy. Change in visual acuity is calculated directly by subtracting LogMAR data, while the average visual acuity is obtained with the arithmetic mean value of the LogMAR data. The mean acuity expressed in LogMAR units can be transformed into a decimal chart for a more comprehensive result. To calculate the average visual acuity directly from the decimal data, the geometric mean value must be used instead of the arithmetic mean value.

Calibration↗
PubMed2003

[Immunosuppression in corneal transplantation].

Rejection is the leading cause of corneal graft failure, induced by loss of the so-called eye immune privilege. Prevention of graft rejection with immunosuppressive therapy is then necessary. Topical corticosteroids are currently the gold standard, and steroids are the only treatment for acute rejection episodes. Steroids are nonspecific immunosuppressive agents, and they can induce glaucoma, cataract, infections, and epithelial defects. Cyclosporin has a specific effect, because it inhibits interleukin-2 transcription and, consequently, the specific activation of T lymphocytes. When cyclosporin is given orally, it effectively prevents graft rejection in high-risk recipients, but it may induce severe side effects (i.e., systemic hypertension, kidney deficiency, and malignant tumor induction). When cyclosporin is given topically, it can effectively replace steroids in case of dexamethasone-induced glaucoma and graft infection, but it can also induce serious corneal epithelial defects. Cyclosporin is not a treatment for acute rejection episodes. Mycophenolate mofetil and FK 506 are promising drugs, but currently they cannot be used routinely to prevent corneal graft rejection.

Adrenal Cortex Hormones↗
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↗