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O Touzeau

Publications and source records attributed to O Touzeau.

47 records · Page 3Linked to original sources
PubMed1999

Effects of penetrating keratoplasty suture removal on corneal topography and refraction.

PURPOSE: To study the refractive and topographic modifications induced by penetrating keratoplasty suture removal. METHODS: We retrospectively studied 50 corneas from 50 patients who had undergone penetrating keratoplasty. All of the eyes were examined before and after all sutures were removed at 10.8+/-4.7 months and 20.3+/-7.9 months after keratoplasty. Subjective refraction, best spectacle-corrected visual acuity (LogMAR units), and corneal topography (EyeSys 2000R device) were recorded. RESULTS: Suture removal decreased the subjective cylinder by an average of 0.91+/-2.32 D (p = 0.004) and modified the corneal topographic pattern (p = 0.03) and shape (p < 0.001) distribution. The change in subjective cylinder correlated with the variation of the steepest meridian power (r(s) = 0.46; p < 0.001). It correlated with the change in topographic pattern (r(s) = 0.59; p < 0.001). The subjective spherical equivalent increased (hyperopization) by an average of 0.61+/-2.24 D (p = 0.01). After suture removal, the prolate shape was less frequent, and the oblate shape was more frequent than before suture removal. Best spectacle-corrected visual acuity increased by an average of 0.8+/-2.0 lines (p = 0.004). The change in subjective cylinder correlated with the change in visual acuity (r(s) = 0.36; p = 0.006). CONCLUSION: Suture removal modifies the corneal topographic pattern and shape. It decreases the subjective cylinder and induces an hyperopization. Visual-acuity improvement after suture removal mainly is explained by the decrease in astigmatism. Suture removal seems particularly helpful in corneas with a bow-tie pattern.

Adolescent↗
PubMed1999

The triple procedure: in the bag placement versus ciliary sulcus placement of the intraocular lens.

AIMS: To evaluate the influence of intraocular lens (IOL) placement on triple procedure clinical results and to investigate whether it is appropriate to use phacoemulsification in patients with large lens nucleus. METHODS: 40 consecutive penetrating keratoplasties combined with cataract extraction performed in a single institution were studied. Whenever possible a capsulorhexis was performed and the IOL was placed into the capsular bag. Phacoemulsification was used when the nucleus was too large to pass through the capsulorhexis. RESULTS: Out of 25 patients with an intact capsulorhexis phacoemulsification was used in 13 (52.0%) whereas the entire nucleus passed through the capsulorhexis in the remaining 12 patients (48%). The average 12 month visual acuity was 0.46 (SD 0.21) in patients with in the bag IOL (n = 23) and 0.29 (0.08) in patients with ciliary sulcus IOL (n = 13) (p = 0.04). Elevated intraocular pressure occurred in 26.1% (6/23) of patients with in the bag IOL and 61.5% (8/13) of patients with ciliary sulcus IOL (p = 0.08). The average postoperative graft thickness at 18 months was 552 (27) microns in the former group and 650 (29) microns in the latter group (p = 0.04). No significant difference in graft survival, postoperative endothelial cell density, astigmatism, and videokeratoscopic measurements was found between both groups. CONCLUSION: In the bag placement of the intraocular lens during the triple procedure results in better outcome of transplantation than ciliary sulcus placement of the IOL. Phacoemulsification allows removal of large nuclei through a 5 mm capsulorhexis without performing relaxing incisions out towards the periphery of the capsule.

Adolescent↗
PubMed1999

[Effect of sodium hyaluronate administered at the end of penetrating keratoplasty on reepithelialization of the graft].

PURPOSE: To investigate the effect of sodium hyaluronate on reepithelialization time after penetrating keratoplaty. METHODS: We prospectly studied 56 consecutive penetrating keratoplasties. One group of patients (n = 22) received dexamethasone ointment at the end of surgery. The second group (n = 34) received sodium hyaluronate and topical dexamethasone. Postoperative reepithelialization time and graft central thickness were recorded. RESULTS: There was no statistical difference between both groups for epithelialization (4.6 + 3.2 days in the hyaluronate group and 4.4 + 2.3 days in the dexamathasone group) and for graft thickness at day one (710 + 85 microns for the former group and 713 + 84 microns for the latter group) and at day of reepithelialization (663 + 80 microns for the former group and 703 + 99 microns for the latter group). The epithelium aspect was different at the first postoperative day between both groups. CONCLUSION: The use of sodium hyaluronate at the end of penetrating keratoplasty improves the graft epithelium aspect at the first postoperative day, but it does not influence reepithelialization time. Further studies are needed to investigate the mechanism of sodium hyaluronate effect on corneal epithelium.

Aged↗
PubMed1999

[Comparison of EyeSys videokeratoscope algorithms in the evaluation of idiopathic and postoperative astigmatism].

PURPOSE: To compare the accuracy and reproducibility of the Eye Sys videokeratoscope algorithms for analyzing idiopathic and surgery-induced astigmatism analysis. METHODS: Refractive astigmatism, videokeratoscopy (axial, tangential and refractive power), autorefractometry, autokeratometry, and keratometry were recorded in 20 patients with idiopathic astigmatism, 40 patients who had undergone cataract surgery and 40 patients who had undergone penetrating keratoplasty. For each eye, 2 successive videokeratoscopy were recorded. RESULTS: Both cylinder and axis provided by the tangential algorithm are significantly less reproducible than the cylinder and axis provided by the axial and refractive algorithms (P < 0.001). Cylinders provided by the axial and refractive algorithms showed a stronger correlation with subjective cylinder (rs > 0.89; p < 0.001) than the cylinder provided by the tangential algorithm (rs = 0.66; p < 0.001). Both keratometric axis and autokeratometric axis showed the strongest correlation with subjective axis (rs > 0.92; p < 0.001). The accuracy and reproducibility were higher for the topographic "bow tie" patterns than for the other topographic patterns. CONCLUSION: The axial and refractive algorithms of the Eye Sys videokeratoscope are more accurate and reproducible than the tangential algorithm for analyzing idiopathic or surgery-induced astigmatism.

Algorithms↗
PubMed1998

Light microscopic evaluation of human donor corneal stroma during organ culture.

PURPOSE: To try to facilitate evaluation of corneal stroma during organ culture by means of light microscopy. METHODS: Corneal stroma of 53 consecutive organ-cultured corneas was studied by means of light microscopy during endothelial quality control. Out of 9 corneas with bad stromal evaluation, 2 were studied by means of transmission electron microscopy, and 7 were grafted. From the remaining 44 corneas with a normal light microscopic appearance, 35 were grafted. RESULTS: Stromal abnormalities consisted of bright visible structures with a cell-like shape corresponding to keratocyte injuries (i.e. cellular edema, light and dark vacuoles, cell membrane disruption and, finally, internal cytolysis) as observed by TEM. At 3 months postoperatively no clinical differences between the two groups of transplants were observed. CONCLUSION: Corneal stroma can be evaluated qualitatively and easily by means of light microscopy during organ culture. Further studies are needed to investigate whether the presence of lysed keratocytes in the graft's stroma actually influences the outcome of transplantation.

Adult↗
PubMed1998

Donor organ cultured corneal tissue selection before penetrating keratoplasty.

AIMS: Donor organ cultured corneal tissue selection before penetrating keratoplasty is carried out by taking into account different variables. The objective was to identify preoperative variables which are significantly and independently associated with transplant outcome and should effectively be taken into account before transplantation. METHODS: 231 consecutive penetrating keratoplasties were prospectively studied using organ cultured tissue. Morphometric analysis of the donor corneal endothelium was performed before transplantation. Graft survival and endothelial cell density, during the second year following transplantation, were studied both at a univariate and multivariate level. RESULTS: Recipient age, recipient rejection status, and preoperative diagnosis significantly influenced graft survival. Graft survival was higher when using corneal tissue from donors older than 80 years. Postoperative endothelial density decreased with preservation time and coefficient of variation after preservation. It increased with endothelial cell density after preservation and deswelling time, and correlated with preoperative diagnosis. CONCLUSION: Organ cultured corneas with endothelial cell density after preservation < 2000 cells/mm2, and high coefficient of variation, may be discarded before transplantation. Corneas should be preserved for less than 3 weeks, and allowed to deswell before transplantation for 2 or 3 days rather than 1 day.

Adolescent↗
PubMed1997

[Value of implantation in the capsular bag during combined operation of penetrating keratoplasty and cataract surgery].

PURPOSE: To evaluate the clinical results of the triple procedure performed using phacoemulsification. METHODS: We prospectively studied 23 consecutive triple procedures carried out during a 3-year period. The average follow-up was 18 months. The main indications for grafting were Fuchs' endothelial dystrophy (30%) and infectious keratitis (26%). RESULTS: A capsulorrhexis was performed in 70% of the cases whereas a "can opener" was performed in the remaining 30%. A divide and conquer phacoemulsification method was used in 43% of the cases. Hydrodissection was used for lens removing in 27% of the cases. The posterior lens capsule was inadvertently broken and a flexible anterior chamber lens was inserted in one case. Twenty-two posterior chamber lenses were inserted in the capsular bag (16) or in the sulcus (6). The estimated 1-year graft survival was 76.8% overall, and 92.9% when high-risk recipients were excluded. Causes of graft failure were immune rejection (n = 4), persistent epithelial defect (n = 1) and uncontrolled glaucoma (n = 1). The average endothelial density during the second year was 1,401 cell/mm2. Average corrected visual acuity was 20/45 at 12 months. Average astigmatism was 3.9 D. No retinal complication was observed. CONCLUSIONS: In-the-bag placement of posterior chamber lens is a safe and useful technique during the triple procedure. Phacoemulsification may be useful when the nucleus is hard and voluminous.

Aged↗
PubMed1997

[Astigmatism after penetrating keratoplasty. Videokeratoscopic analysis on a series of 60 grafts].

PURPOSE: To study the factors which induce post keratoplasty astigmatism. To assess the reliability of different methods in the astigmatism measurement and to study the visual acuity predicting factors. METHODS: We retrospectively studied the corneal topography in 60 eyes with penetrating keratoplasty after suture removal, using the CAS* (Eye Sys). The diagnosis was keratoconus in 65% of the cases and bullous keratopathy in 15% of the cases. The graft was secured with a single running suture in 38.3% of the cases, interrupted sutures in 23.3% of the cases, or a combination of both running and interrupted sutures in remaining 28.3%. RESULTS: The suture method, diagnosis and surgeon did not influence subjective refraction nor visual acuity. The topographic pattern correlated with subjective cylinder (rs = 0.52 p = 0.02). The refractive power cylinder ("Holladay diagnostic summary") correlated well with subjective cylinder (rs = 0.81 p < 0.001) and visual acuity (rs = -0.63; p < 0.001). The Javal keratometry remains the best method to measure astigmatism axis (rs = 0.58; p < 0.001). CONCLUSIONS: The Holladay diagnostic summary (refractive power) is a useful tool for evaluating qualitative outcome of corneal transplantation.

Adolescent↗
PubMedDate not supplied

Videokeratography, keratometry, and refraction after penetrating keratoplasty.

PURPOSE: To identify the correlation between videokeratography, autorefractometry, autokeratometry, and keratometry measurements and the subjective manifest refraction and spectacle-corrected visual acuity after penetrating keratoplasty. METHODS: We studied 100 eyes from 100 patients that had undergone penetrating keratoplasty. All eyes were examined by videokeratography (EyeSys 2000) (axial, tangential, and refractive power maps), autorefractometry, autokeratometry, and keratometry. Measurements were made at an an average of 19 +/- 9 months after surgery. Postoperative refractive astigmatism, spherical equivalent refraction, and spectacle-corrected visual acuity were studied by regression analysis. RESULTS: Both the total topographic cylinder measured by the refractive power map and topographic cylinder measured by the axial power map showed the strongest correlation with the manifest refractive cylinder (rs = +0.89, P < .001). The axis of astigmatism determined by keratometry and autokeratometry showed the strongest correlation with the subjective manifest refraction axis (rs = +0.87, P < .001). The total topographic cylinder showed the strongest correlation with the spectacle-corrected visual acuity (rs = +0.38, P = .001); however the topographic indices of predicted corneal acuity, corneal acuity, corneal uniformity index, asphericity, and refractive power symmetry did not correlate with spectacle-corrected visual acuity. CONCLUSION: Measurement of astigmatism after penetrating keratoplasty can be made more accurate by using videokeratographic measurements to supplement retinoscopic and manifest refraction. Other useful methods for predicting the axis of refractive astigmatism include keratometry, autokeratometry, and autorefractometry. In this study, indices designed to measure corneal surface irregularity failed to predict visual acuity after penetrating keratoplasty.

Astigmatism↗
PubMedDate not supplied

[Use of topical cyclosporin in microcrystalline keratopathy due to Streptococcus].

Infectious crystalline keratopathy is an exceptional but serious complication of penetrating keratoplasty. Streptococcus viridans and a steroid treatment are very often found. The treatment is always lengthy and difficult. The high number of bacteria and the steroid treatment, necessary to prevent rejection, worsen the infection. We report a case of Streptococcus crystalline keratopathy that evolved, despite the treatment, simultaneously toward abscess and acute rejection. Topical cyclosporin treatment was used to maintain an immunosuppression without worsening the infection.

Administration, Topical↗