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O Touzeau

Publications and source records attributed to O Touzeau.

At least 19 recordsLinked to original sources

[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↗

[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↗

[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↗

[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↗

[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↗

[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↗

[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↗

[Corneal acid burning after facial peeling].

We describe the case of a 66-year-old woman who had previously undergone facial peeling and developed severe bilateral corneal burn due to direct contact Exopeel((R)) with her eyes. Despite medical treatment and an amniotic membrane graft, deep stromal opacity persisted in one eye.

Aged↗

[Orbscan: a new device for iridocorneal angle measurement].

PURPOSE: To evaluate the accuracy and reproducibility of iridocorneal angle measurement obtained with a slit-lamp method (Orbscan). METHODS: The iridocorneal angle was measured in 100 normal eyes of 50 patients using the Orbscan II device. Angles were measured in eight meridians using both the "plane" and "polynomial" modes. For each eye, two exams were taken successively and the reproducibility was calculated by analyzing the difference between both measurements. Angle value was correlated with subjective spherical equivalent and other biometric measurements obtained by Orbscan (i.e., anterior chamber depth, axial length, corneal diameter). RESULTS: Reproducibility of the angle measurement was significantly better with the plane mode than with the polynomial mode (5.4%+/-4.7 versus 7.2%+/-6.2; p<0.001). Reproducibility significantly varied with localization (p<0.001). Significant differences were found between reconstruction modes (49.3 degrees +/-4.6 degrees for plane mode versus 42.8 degrees +/-6.7 degrees for the polynomial mode; p<0.001) and according to localization (p=0.02). Correlation with the other biometric measurements was higher for the plane mode than for the polynomial mode. Angle measurement with the plane mode showed significant correlation with subjective spherical equivalent (r(s)=-0.59; p<0.001), the anterior chamber depth measurement (r(s)=-0.74; p<0.001), the axial length measurement (r(s)=-0.34; p<0.002), and the corneal diameter measurement (r(s)=-0.34; p<0.002). CONCLUSION: The iridocorneal angle measure obtained with the plane mode showed high reproducibility and it significantly correlated with clinical parameters. It appears to be useful for clinical application.

Adolescent↗

[Amniotic membrane transplantation in severe corneal epithelial diseases. Preliminary results].

PURPOSE: To evaluate amniotic membrane transplantation (AMT) in severe corneal epithelial diseases. METHODS: Amniotic membrane transplantation was performed in 14 eyes of 14 patients from four groups: A, five severe ocular burns; B, four cases of cicatricial keratoconjunctivitis; C, three persistent epithelial defects after penetrating keratoplasty; D, two cases of pseudophakic bullous keratopathy. Five patients underwent AMT alone; two patients underwent AMT combined with limbal transplantation; the other three patients had limbal transplantation performed before AMT. Eight patients required combined penetrating keratoplasty. Patients with corneal stable reepithelialization, no corneal neovascularization, and no recurrence of the initial pathology were considered successful. RESULTS: The mean follow-up was 7+/-3 months. All but three patients underwent corneal reepithelialization within 6 weeks of AMT, with a mean healing time of 31+/-23 days. The success rate was 75% at 6 months (Kaplan-Meier method). Three of four procedures in group B failed. In eight patients, visual acuity improved, in one it worsened, and in the last five patients it remained unchanged. Visual acuity increased by an average of 7+/-9 lines. CONCLUSION: AMT is a useful technique for ocular surface reconstruction, especially in association with limbal transplantation. It could also improve the prognosis of penetrating keratoplasty in patients with severe corneal conditions.

Adolescent↗

[Fungal keratitis at the Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts: retrospective study of 19 cases].

PURPOSE: To report the spectrum of fungal keratitis at the Centre Hospitalier National d'Ophtalmologie XV-XX, Paris. METHODS: We reviewed 19 cases of fungal keratitis from January 1993 to January 2001. We evaluated the different risk factors, fungal identification, topical and systemic antifungal therapy, surgical treatment and outcome. RESULTS: Nineteen patients were included, 7 women and 12 men, with visual acuity ranging from 9/10 to no perception of light. The mean age was 56.2 years. Patients were hospitalized for an average stay of 16.3 days and all received a diagnostic and therapeutic scraping and 16 received a local antifungal treatment. The most common risk factors were topical steroid treatment (42.1%), corneal graft (31.6%), trauma or foreign body (31.6%). The mean delay between the first signs and fungal keratitis diagnosis was 14 days. Yeast as Candida parapsilosis and albicans were the most frequently isolated fungi (58%), followed by Aspergillus sp. (21%) and Fusarium sp. (21%). The most commonly used topical treatment was amphotericin B, and itraconazole was used as systemic treatment. Five patients had evisceration, 6 had penetrating keratoplasty and 5 retained leukoma. CONCLUSION: Candida was the most frequently isolated fungi and topical steroid treatment the main risk factor. The prognosis is relatively poor (26% of lost vision) because of a delay in diagnosis and other previous ocular pathology or surgery.

Adolescent↗

Outcome of Corneal transplantation rejection.

PURPOSE: To identify predictive factors for reversibility of corneal graft rejection. METHODS: The study design was a prospective cohort study. Among 440 consecutive penetrating keratoplasties performed at our institution, 79 grafts from 79 patients who developed signs of transplant rejection were included. Donor, recipient, surgical, and rejection variables were studied, at both univariate and multivariate levels. RESULTS: The rate of reversibility was 51% (40/79). The average postoperative time of rejection was 10.5 +/- 9.3 months, and the average time of visual acuity recovery in patients with reversible rejection was 2.4 +/- 2.3 months. In logistic regression, only two variables significantly influenced the rate of reversibility. The preoperative diagnosis (p = 0.04) influenced the rate of rejection reversibility; patients with bullous keratopathy or regraft were more likely to experience irreversible rejection than patients with keratoconus or Fuchs' dystrophy. The average graft thickness at the time of rejection diagnosis was 774 +/- 129 microm in patients with irreversible rejection and 681 +/- 118 microm in patients with reversible rejection (p = 0.001). CONCLUSION: Rejection was reversible in half of the cases. Rejection was more likely to be irreversible in patients with marked increase in graft thickness and in patients transplanted for bullous keratopathy or graft failure. Donor variables did not influence rejection reversibility.

Adolescent↗

Screening human donor corneas during organ culture for the presence of guttae.

AIMS: To detect the presence of guttae by means of light microscopy during organ culture and to evaluate the influence of the presence of guttae in the donor tissue on transplantation outcome. METHODS: Donor corneas were investigated for the presence of guttae by means of light microscopy at the end of organ culture. Recipient corneal buttons from patients with severe Fuchs' dystrophy and donor corneas with advanced guttae were first studied by light microscopy and subsequently by transmission electron microscopy. Lastly, 168 consecutive donor corneas were evaluated for the presence of guttae and issued for transplantation. RESULTS: Corneal specimens with Fuchs' dystrophy displayed numerous round highly reflecting guttae at the level of the corneal endothelium. Donor corneas with advanced guttae showed less numerous guttae. Among 168 organ cultured donor corneas issued for transplantation, low density guttae were found in 43 (25.6%) corneas. The endothelial cell density and figure coefficient were significantly lower and organ culture time was significantly higher in the cornea guttata group than in the control group. The presence of grouped guttae significantly decreased the adjusted graft survival. The incidence of postoperative stage 3 cornea guttata was significantly higher when grouped guttae were found (5/6) than when no guttae or scattered guttae were found (8/101). CONCLUSION: Cornea guttata can be detected during organ culture by means of light microscopy. It is associated with a decrease in endothelial cell figure coefficient and cell density. The presence of grouped guttae is associated with poorer graft survival and more frequent stage 3 cornea guttata in the graft after transplantation.

Adolescent↗

[Correlation between corneal topography and subjective refraction in idiopathic and surgery-induced astigmatism].

PURPOSE: To study the correlation between subjective refraction and corneal topography. To compare the topographic analysis of surgically induced astigmatism (cataract and penetrating keratoplasty) with that of idiopathic astigmatism. METHODS: Subjective astigmatism, subjective spherical equivalent, best spectacle-corrected visual acuity (LogMAR units), and videokeratoscopy using the EyeSys 2000((R)) device (axial, tangential, and refractive power) were recorded in 100 eyes with idiopathic astigmatism, 100 eyes after cataract surgery, and 100 eyes after penetrating keratoplasty. Topographies were classified according to pattern (Bogan classification) and asphericity (shape factor: prolate or oblate). RESULTS: The asphericity shape distribution was significantly different between the 3 groups (p<0.001). The shape of idiopathic astigmatism was almost always prolate (90%) whereas the oblate shape was more frequent in the penetrating keratoplasty group (75%). There was no significant difference in topographic pattern distribution between the 3 groups (p=0.11). The asymmetric bow tie pattern was the most common topographic pattern. Topography pattern classification was significantly correlated with the subjective astigmatic cylinder. (r(s)=0.60, p<0.001). Unlike the round and oval patterns, the bow tie pattern was associated with the high subjective cylinder. Correlation between the subjective cylinder, the refractive power cylinder, and the axial power cylinder was strong (r(s)=0.92 p<0.001), but it was weak for the tangential power cylinder (r(s)=0.72 p<0.001). The correlation between the subjective spherical equivalent and central cornea power was poor (r(s)<0.37, p<0.001). Subjective astigmatic cylinder showed the strongest correlation with best spectacle-corrected visual acuity (r(s)=0.70, p<0.001), whereas the predicted corneal acuity, corneal uniformity index, asphericity, and refractive power symmetry index were poorly correlated with it (r(s)<0.54, p<0.001). CONCLUSION: Despite the difference in the asphericity shape, the topographic pattern was similar in the 3 groups. The pattern type was significantly correlated with the subjective astigmatic cylinder. Topographic indices failed to predict visual acuity, while the subjective cylinder showed a strong correlation with visual acuity.

Astigmatism↗

[Urrets-Zavalia syndrome].

We report four cases of Urrets-Zavalia Syndrome (fixed dilated pupil with iris atrophy) observed after penetrating keratoplasty. The precise etiology of the syndrome is uncertain and different mechanisms are reviewed. Care should be taken to avoid the use of mydriatic eye drops after penetrating keratoplasty.

Adult↗

[Change in refraction and topography after penetrating keratoplasty suture removal].

PURPOSE: To study the refractive and topographic modifications induced by penetrating keratoplasty suture removal. METHODS: We prospectively studied 80 corneas from 80 patients who had undergone penetrating keratoplasty. All of the eyes were examined before and after all sutures were removed, respectively at 10.9 5.1 months and 21.5 9.6 months after keratoplasty. Subjective refraction, best spectacle-corrected visual acuity (LogMAR units), keratometry, and corneal topography using the EyeSys 2000((R)) device (axial tangential and refractive power) were recorded. Topographies were classified according to the pattern (Bogan classification) and the asphericity shape (prolate and oblate). RESULTS: Best spectacle-corrected visual acuity (Log MAR units) increased significantly after suture removal (1.1 1.9 lines, plt; 0.001). Suture removal decreased the subjective cylinder (5.01 D 2.06 with suture, 4.11 2.08 without suture; p=0.009). The change in subjective cylinder correlated with the change in topographic pattern(s)=0.67 p<0.001). Conversely to the "bow tie" patterns, the other topographic patterns were more frequent after suture removal. The change in visual acuity was essentially explained by the change in subjective cylinder(s)=0.40 p=0.002). The average central corneal power decreased significantly after suture removal by 0.83 to 1.81 D (p<0.001), whereas the subjective spherical equivalent increased (hyperopization) (-4.07D 3.73 with suture, -3.48 3.40 without suture; p=0.02). The change in central corneal power significantly correlated with the change in subjective spherical equivalent (r(s)()>0.30 plt; 0.001). The corneal power of the mid-periphery did not significantly change after suture removal. Suture removal significantly modified the asphericity shape distribution. (majority of prolate shape with suture, majority of oblate shape without suture, p<0.001). CONCLUSION: Keratoplasty sutures induce a central bulge in the corneal graft. Suture removal induces a decrease in the subjective cylinder and it increases the subjective spherical equivalent (hyperopization) through a decrease in the central corneal power. Suture removal modifies the corneal topographic pattern and shape. Visual acuity improvement after suture removal is mainly explained by the decrease in subjective astigmatism.

Adolescent↗

[Ocular biometric measurements with a slit-lamp method (Orbscan)].

PURPOSE: To evaluate the accuracy and reproducibility of the biometric measurements obtained with the Orbscan((R)) device in normal eyes. METHODS: Anterior chamber depth, axial length, and corneal diameter were studied in 50 normal eyes of 25 patients using the Orbscan((R)) device and A-Scan ultrasonography. For each eye, two exams were done successively and reproducibility was calculated by analyzing the difference between both measurements. RESULTS: The reproducibility of anterior chamber depth and corneal diameter measurements obtained by Orbscan((R)) was high (respectively 0.721.25% and 0.831.40%). The anterior chamber depth measurements by Orbscan((R)) and A-Scan ultrasonography were strongly correlated (rs=0.92;p<0.001). The axial length measurement obtained with the Orbscan((R)) device was less reproducible (3.554.11%). For the axial length, the Orbscan((R)) measurements and A-Scan ultrasonography measurement was poorly correlated. (rs=0.64; p<0.001). CONCLUSION: The anterior chamber depth measurement obtained with the Orbscan((R)) device showed high reproducibility and it was strongly correlated with the measurement obtained by A-Scan ultrasonography. Axial length measurement obtained with the Orbscan((R)) device was less reproducible and poorly correlated with the A-Scan ultrasonography measurement. It was not relevant for clinical application.

Adult↗