Myopic outcomes after excimer laser phototherapeutic keratectomy (PTK).

PURPOSE: To evaluate refractive outcomes following excimer laser phototherapeutic keratectomy (PTK). METHODS: A retrospective non-randomized review of refractive outcomes of 146 consecutive eyes treated with excimer laser PTK at the Rothschild Foundation, Paris, France. Inclusion criteria were all patients undergoing PTK laser using a flying spot excimer laser system (Wavelight Allegretto, Alcon Surgical, Inc.) from October 2016 to June 2018. Exclusion criteria were incomplete data, irregular astigmatism and dystrophies of uncertain diagnosis. Preoperative diagnoses included recurrent corneal erosion syndrome without dystrophy and Cogan corneal dystrophies. The primary outcome measure was the change in spherical equivalent (SEQ) at M1 post PTK. The secondary outcome measure was the creation of a regression equation for predicting refractive outcomes after PTK, by analyzing the effect of ablation depth (AD) and optical zone (OZ) diameter. RESULTS: Fifty-eight eyes of 54 patients were included. The mean OZ was 7.352 mm±0.622. The mean AD was 18.362µm±21.406. At M1 postoperatively, the mean SEQ was -2.485 D±2.628 and mean final SEQ was -1.052 D±1.260. Both OZ and AD were independent variables with significant effects on the final visual outcome. A regression equation for predicting refractive outcomes was established. No complications were observed. CONCLUSION: The Wavelight flying spot excimer laser system produces myopic outcomes following PTK. Both OZ and AD are significant variables. A regression equation was created and may aid in prediction of refractive outcomes following PTK.

High-resolution imaging of photoreceptors in healthy human eyes using an adaptive optics retinal camera.

PURPOSE: To determine the effects of age on perifoveal cone density in healthy subjects using adaptive optics. METHODS: Healthy subjects of various ages were imaged using an adaptive optics retinal camera (RTX-1® Imagine Eyes, Orsay, France). All patients underwent a comprehensive ophthalmologic examination and retinal imaging using spectral-domain optical coherence tomography (Spectralis®, Heidelberg Engineering, Heidelberg, Germany). Cone density together with cone spacing and cone mosaic packing were measured in the nasal and temporal area 450 µm from the fovea. A multivariate analysis was performed to determine which of the following parameters were related to a decrease in cone density: age, axial length, central macular thickness, and retrofoveal choroidal thickness. RESULTS: One hundred and sixty-seven eyes of 101 subjects aged 6-78 years were studied. Perifoveal cone density significantly decreased with age (R2 = 0.17, p<0.01). Inversely, cone spacing increased with age (R2=0.18, p<0.01). There was no change in the cone packing mosaic (p>0.05). The mean coefficient of variation between fellow eyes was 3.9%. Age and axial length were related to a cone density decrease, while choroidal and retinal thicknesses did not affect cone metrics in healthy subjects. CONCLUSIONS: A moderate perifoveal cone loss occurs with age. The precise consequences of these findings on visual function should be investigated. In addition to a better understanding of normal retinal anatomy, these results could act as a comparative database for further studies on normal and diseased retinas.

[Reproducibility of visual acuity measurement using the ETDRS chart in daily clinical practice]. / Reproductibilité des mesures de l'acuité visuelle par échelle ETDRS en pratique quotidienne.

OBJECTIVE: To evaluate reproducibility of visual acuity measurements using the ETDRS chart at successive monthly visits in patients with stable macular pathology. MATERIALS AND METHODS: Visual acuity was measured using the ETDRS chart at 6 consecutive monthly examinations. Relative standard deviation of visual acuity was measured for every patient. Analysis of the results by type of pathology, age, sex and examiner experience was performed. RESULTS: One hundred and three patients were included. Mean patient age was 72.7±12.4 years. A total of 68.9% of the patients suffered from AMD. Mean visual acuity was 47.4±9.5 ETDRS letters. Mean reproducibility of the measurement estimated by relative standard deviation over the 618 examinations was 5.4±2.8% (CI95%: 4.9-6%) with extremes values of 0.4 and 7.8 letters. Relative standard deviation corresponding to the mean ETDRS score (47.4 letters) was 2.5 letters. Reproducibility of visual acuity measurement was better in patients under 76 years, pseudophakes, or with a visual acuity better than 50 letters (P<0.05). Variability of the measurement increased with age (r2=13%, P=0.001) and with low visual acuity (r2=35%, P<0.0001) and was larger in patients suffering from AMD than those suffering from other conditions. Examiner experience did not seem to influence reproducibility of the measurement.

Quantification of cone loss after surgery for retinal detachment involving the macula using adaptive optics.

AIMS: To image the cones in eyes with anatomically successful repair of retinal detachment (RD) involving the macula and in healthy fellow eyes using an adaptive optics (AO) camera and to correlate the results to clinical outcomes. METHODS: Twenty-one patients (42 eyes) operated for macula-off RD were imaged 6 weeks after surgery using an AO camera (RTX 1, Imagine Eyes, Orsay, France). Cone density (cells/mm(2)), spacing between cells (µm) and the percentage of cones with six neighbours were measured. Best-corrected visual acuity (BCVA) and thickness of the inner segment ellipsoid (ISe) band imaged by SD-optical coherence tomography were also measured. RESULTS: The parafoveal cone density was decreased in eyes operated for RD (mean ± SD 14,576 ± 4035/mm(2)) compared with fellow eyes (20,589 ± 2350/mm(2)) (p=0.0001). There was also an increase in cone spacing (10.3 ± 2.6 vs 8.0 ± 1.0.9 µm, respectively, p<0.0001). The nearest-neighbour analysis revealed a reduction in the percentage of cones with six neighbours (36.5 ± 4.2 vs 42.7 ± 4.6%, p=0.0003). The ISe thickness, thinner in the operated eyes, was correlated to the cone density (r=0.62, p<0.0001). BCVA was significantly correlated to cone density (r=0.8, p<0.001). CONCLUSIONS: There was a decrease in the cone density after RD with an estimated loss of one-third of the cones. Postoperative visual acuity was highly correlated with the cone density. AO may be a valuable prognostic tool after RD surgery.

[Side effects and patients expectations after vestibular tests]. / Effets secondaires et expectatives des patients après tests vestibulaires.

OBJECTIVE: Patients satisfaction and side effects assessment after vestibular tests. MATERIALS AND METHODS: Questionnaires were sent to 150 patients after vestibular testing in 2006. Forty-two questionnaires were sent back to us. On each questionnaire there were 5 questions regarding patient expectations, 4 questions about side effects after vestibular tests and one question was related to follow-up medical attention. RESULTS: Most of the patients think that the delay between clinical consultation and vestibular test was not too long. Information patients received beforehand regarding vestibular tests aim, duration, possible side effects and diagnostic expectations are good enough for most of the patients. However patient's assessment of the informed consent document and location of vestibular tests is diverse. The vast majority of patients feel "very important" to receive information about vestibular tests results on the same day. For most of the subjects caloric test is the most disconfortable tests. In the following days, more than half of the subjects feel vestibular symptoms. The most frequent suggestion we received from patients is to give them a phone calls after vestibular tests. CONCLUSION: It is worth mentioning the importance of informing the patient about vestibular test results upon completion. Our aim is to make some changes on the informed consent document given to patients and to make a phone call to patients after vestibular tests.