Auswirkungen auf den vorderen Augenabschnitt beim Andocken eines Femtosekundenlasers an das Patienteninterface

2021 ◽  
Vol 1 (5) ◽  
pp. 164-171

Purpose. To compare the intraoperative OCT (optical coherence tomographer) of the femtosecond laser LenSx (Alcon Pharma GmbH, Freiburg) with a Scheimpflug-tomographer and an anterior segment OCT and thus to investigate a possible influence on the anterior segment of the eye when docking the patient’s interface. Material and Methods. A prospective cross-sectional study was conducted with 57 subjects who underwent a planned femtosecond laser-assisted cataract surgery or refractive lens exchange. The eye to be operated on was measured prior to the operation in mydriasis with the Visante OCT (Carl Zeiss Meditec AG, Jena) and the Pentacam AXL (Oculus Optikgeräte GmbH, Wetzlar). During the surgery, images of the anterior segment of the eye were taken by the integrated intraoperative OCT of the laser, which were evaluated afterwards and compared to the values of the other devices. The parameters examined were the internal anterior chamber depth (ACD), nasal and temporal chamber angles, central corneal thickness (CCT) and central lens thickness (LT). Results. The comparison of the intraoperative OCT and the two other devices showed clinically relevant differences in all parameters. The intraoperative OCT showed a 9.19 ± 27.55 μm larger CCT, 0.96 mm (median difference) larger LT, 0.05 mm smaller ACD than the Pentacam AXL and a 21.36 ± 25.50 μm larger CCT, 0.10 mm (median difference) smaller ACD than the Visante OCT. Conclusion. The comparison of the intraoperative OCT with the Visante OCT and the Pentacam AXL shows clinically relevant differences. Changes in the anterior segment of the eye may be due to errors in measurement or docking of the patient’s interface. Keywords. femtosecond laser, OCT, anterior segment of the eye, cataract surgery, refractive lens exchange

2016 ◽  
Vol 27 (4) ◽  
pp. 417-422 ◽  
Author(s):  
José Ignacio Fernández-Vigo ◽  
Lucía De-Pablo-Gómez-De-Liaño ◽  
Cristina Fernández-Vigo ◽  
Inés Sánchez-Guillén ◽  
Enrique Santos-Bueso ◽  
...  

Purpose To determine the prevalence of trabecular-iris contact (TIC) and quantify this contact in healthy Caucasian individuals using Fourier-domain optical coherence tomography (FD-OCT). Methods For this cross-sectional study, 2,012 eyes of 1,006 healthy subjects were recruited among individuals undergoing a routine ophthalmologic checkup. In each participant, age, sex, intraocular pressure, and spherical refractive error were first recorded along with anterior chamber depth and volume, central corneal thickness measured with the Pentacam, and axial length with the IOLMaster. Anterior chamber angle variables and the presence of TIC in the horizontal quadrants were determined by anterior segment FD-OCT (RTVue 100®). When TIC was observed, TIC length (TICL) and its percentage in relation to the length of the trabecular meshwork (TICL percentage) were also measured. Results Trabecular-iris contact in the horizontal quadrants was observed in 34 eyes of 25 patients, representing 1.6% of the total number of eyes examined. In this subgroup of individuals, mean age was 55.8 years, 84% were women, and spherical refractive error ranged from -0.25 to 8.25 D. Eyes with TIC showed an angle width of less than 23.2 degrees and axial length shorter than 23.7 mm. Mean TICL was 239 ± 79 μm (103-495 μm) and mean TICL percentage was 46.9% ± 13.9% (17.2%-76.3%). Conclusions The prevalence of TIC was low in this population. Fourier-domain optical coherence tomography emerged as useful to assess its prevalence and quantify the extent of TIC.


2018 ◽  
Vol 103 (7) ◽  
pp. 960-965 ◽  
Author(s):  
Ramanjit Sihota ◽  
Neha Kamble ◽  
Ajay K Sharma ◽  
Anju Bhari ◽  
Amisha Gupta ◽  
...  

AimTo evaluate the accuracy of a new, modified grading scheme involving a short vertical slit beam, at the inferior angle for peripheral anterior chamber depth (PAC) and angle estimation and its correlation with anterior segment optical coherence tomography (ASOCT).MethodsA cross-sectional study of consecutive phakic patients, above 40 years of age, was performed. Using a short, vertical slit beam not reaching the pupil, the inferior angle at the sclerolimbal junction was evaluated, photographed and assessed by a ratio of peripheral anterior chamber depth to peripheral corneal thickness (PAC:PCT) and iridocorneal angle (ICA) on ImageJ software. The inferior angle at the same meridian was also recorded on ASOCT.ResultsBased on the PAC:PCT ratio, the subjects were divided into four groups: I (<1/4), II (1/4-1/2), III (>1/2–1) and IV (>1). The clinically assessed angle by short vertical slit beam correlated well with ASOCT values, trabecular-iris angle (TIA) (r=0.918; p<0.001) and scleral spur angle (r=0.903, p<0.001). The mean difference between ICA and TIA on ASOCT was 0.7970; 95% limits of agreement:−5.7670 to 7.3610 (±1.96 SD). For angles graded narrow on ASOCT (TIA <200), using a cut-off of peripheral PAC:PCT <1/4, the area under the curve was 0.918 with a sensitivity of 85.2% and a specificity of 88.2%. There was good agreement between ImageJ parameters with those assessed subjectively on photograph of the slit beam examination by a glaucoma fellow (weighted kappa=0.74) as compared with a general ophthalmologist, where there was moderate agreement (weighted kappa=0.57).ConclusionA short, vertical slit lamp beam evaluation at the inferior angle is an easy and relatively accurate method for both peripheral anterior chamber depth and angle assessment. It correlated well with ASOCT and can be used as a more reliable screening tool to identify eyes with possibly occludable angles.


2019 ◽  
Author(s):  
Bu Ki Kim ◽  
Su Joung Mun ◽  
Young Hoon Yang ◽  
Ji Sun Kim ◽  
Jun Hyung Moon ◽  
...  

Abstract Purpose To compare the changes in the anterior segment after femtosecond laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) using a dual rotating Scheimpflug (DRS) analyzer (Galilei®; Ziemer Ophthalmology, Port, Switzerland). Setting Onnuri smile eye clinic, Seoul, South Korea Design Retrospective Method 218 eyes of 109 patients who underwent FS-LASIK or SMILE for myopic correction were retrospectively studied. Ninety-eight eyes of 49 patients who underwent FS-LASIK were compared to 120 eyes of 60 patients treated with SMILE. A DRS analyzer was used for preoperative and 6-month postoperative anterior segment analyses. Measured variables included the central corneal thickness (CCT), anterior chamber depth (ACD), anterior and posterior keratometry (K), anterior and posterior best-fit sphere radius, and maximum posterior elevation (MPE). Results The estimated lenticule thickness (LT; 87.20 ± 22.87 µm) was significantly thicker in the SMILE group than the ablation depth (69.23 ± 22.24 µm) in the FS-LASIK group. However, there was no significant difference in the CCT decrease using the DRS analyzer. The MPE was significantly increased after both procedures, and there was a statistically significant difference in the change in MPE between the two groups (-1.10 ± 2.12 µm after FS-LASIK; -0.75 ± 2.33 µm after SMILE; p = 0.035). Conclusions The preoperative LT was overestimated using SMILE. Regarding changes in the MPE and posterior K, changes in the posterior corneal surface were greater after FS-LASIK than after SMILE.


2019 ◽  
Author(s):  
Bu Ki Kim ◽  
Su Joung Mun ◽  
Young Hoon Yang ◽  
Ji Sun Kim ◽  
Jun Hyung Moon ◽  
...  

Abstract Background: To compare the changes in the anterior segment after femtosecond laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) using a dual rotating Scheimpflug (DRS) analyzer (Galilei®; Ziemer Ophthalmology, Port, Switzerland).Methods: A total of 218 eyes of 109 patients who underwent FS-LASIK or SMILE for myopic correction were retrospectively studied. Ninety-eight eyes of 49 patients who underwent FS-LASIK were compared to 120 eyes of 60 patients treated with SMILE. A DRS analyzer was used for preoperative and 6-month postoperative anterior segment analyses. Measured variables included the central corneal thickness (CCT), anterior chamber depth (ACD), anterior and posterior keratometry (K), anterior and posterior best-fit sphere radius, and maximum posterior elevation (MPE).Results: After the procedure, the amount of CCT decrease was higher in the SMILE group than in the FS-LASIK group, but it was not statistically significant. The MPE was significantly increased after both procedures (p < 0.001 and p = 0.001 in the FS-LASIK and SMILE groups, respectively), with the amount of elevation being higher after FS-LASIK than after SMILE even though it was not statistically significant. And there was a significant change in the steep and average posterior K in the FS-LASIK group (p = 0.006 and 0.001, respectively), but not in the SMILE group.Conclusions: Regarding changes in the MPE and posterior K, changes in the posterior corneal surface were greater after FS-LASIK than after SMILE.


2019 ◽  
Author(s):  
Bu Ki Kim ◽  
Su Joung Mun ◽  
Young Hoon Yang ◽  
Ji Sun Kim ◽  
Jun Hyung Moon ◽  
...  

Abstract Purpose To compare the changes in the anterior segment after femtosecond laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) using a dual rotating Scheimpflug (DRS) analyzer (Galilei®; Ziemer Ophthalmology, Port, Switzerland). Setting Onnuri smile eye clinic, Seoul, South Korea Design Retrospective Method 218 eyes of 109 patients underwent FS-LASIK or SMILE for myopic correction. Ninety-eight eyes of 49 patients who underwent FS-LASIK were compared to 120 eyes of 60 patients treated with SMILE. A DRS analyzer was used for preoperative and 6-month postoperative anterior segment analyses. Measured variables included the central corneal thickness (CCT), anterior chamber depth (ACD), anterior and posterior keratometry (K), anterior and posterior best-fit sphere radius, and maximum posterior elevation (MPE). Results The estimated lenticule thickness (LT; 87.20 ± 22.87 µm) was significantly thicker in the SMILE group than the ablation depth (69.23 ± 22.24 µm) in the FS-LASIK group. However, there was no significant difference in the CCT decrease using the DRS analyzer. The MPE was significantly increased after both procedures, and there was a statistically significant difference in the change in MPE between the two groups (-1.10 ± 2.12 µm after FS-LASIK; -0.75 ± 2.33 µm after SMILE; p = 0.035). Conclusions The preoperative LT was overestimated using SMILE. Regarding changes in the MPE and posterior K, changes in the posterior corneal surface were greater after FS-LASIK than after SMILE.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Bartosz L. Sikorski ◽  
Pawel Suchon

Purpose. To present a new method of measuring ocular axial dimensions, termed OCT biometry (B-OCT). Design. Observational cross-sectional study and evaluation of new diagnostic technology. Methods. B-OCT was implemented in the spectral domain OCT device for posterior and anterior segment imaging (REVO NX, Optopol Technology). A total of 349 eyes (214 of healthy subjects, 115 of patients with cataract, and 20 with severe macular diseases) were enrolled in the study. The results of B-OCT were compared to swept source OCT-based IOLMaster 700 (Carl Zeiss Meditec). Differences in measurement values between the two biometers were determined using the paired t-test. Agreement was assessed through intraclass correlation coefficients (ICCs) and Bland–Altman plots. Results. B-OCT obtained with REVO NX provides excellent interobserver reproducibility (ICC for: axial length (AXL) = 1.000; central corneal thickness (CCT) = 0.933; anterior chamber depth (ACD) = 0.933; lens thickness (LT) = 0.985) and intraobserver repeatability (ICC for: AXL = 1.000; CCT ≥ 0.994; ACD = 0.998; LT ≥ 0.993). The correlation between measurements made using both devices was outstanding (ICC for: AXL, healthy = 1.000; AXL, cataractous = 1.000; ACD, healthy = 0.998; ACD, cataractous = 0.997; LT, healthy = 0.998; LT, cataractous = 0.997; CCT, healthy = 0.989; CCT, cataractous = 0.979). The mean AXL measurement difference in healthy eyes was −0.001 ± 0.016 mm (the 95% LoA ranged from −0.034 to 0.031); mean ACD difference was 0.000 ± 0.024 mm (95% LoA, −0.047 to 0.047); mean LT difference was −0.002 ± 0.024 mm (95% LoA, −0.050 to 0.046); and mean CCT difference  was −0.8 ± 5.1 μm (95% LoA, −10.81 to 9.26). The mean AXL measurement difference in cataractous eyes was −0.003 ± 0.022 mm (95% LoA, −0.046 to 0.039); mean ACD difference was 0.003 ± 0.029 mm (95% LoA, −0.054 to 0.059); mean LT difference was −0.002 ± 0.025 (95% LoA, −0.051 to 0.048); and mean CCT difference was 2.7 ± 6.4 μm (95% LoA, −9.80 to 15.7). Conclusion. The study shows small, nonsignificant differences between the biometric measurements obtained with REVO NX B-OCT and IOLMaster 700, which is of high significance for IOL power selection. As B-OCT utilizes a conventional OCT device, the measurements of the ocular axial dimensions are combined with high-resolution macular scans for the simultaneous assessment of central retina as a part of screening for macular pathology. The presented method is the first spectral domain OCT-based biometry technique and the only one integrated into a standard OCT device. Thus, it brings novel functionality to OCT technology.


2017 ◽  
Vol 76 (1) ◽  
Author(s):  
Nishanee Rampersad ◽  
Rekha Hansraj

Background: Assessment of intraocular pressure (IOP) is an important test in glaucoma. In addition, anterior segment variables may be useful in screening for glaucoma risk. Studies have investigated the associations between IOP and anterior segment variables using traditional statistical methods. The classification and regression tree (CART) method provides another dimension to detect important variables in a relationship automatically.Aim: To identify the critical factors that influence IOP using a regression tree.Methods: A quantitative cross-sectional research design was used. Anterior segment variables were measured in 700 participants using the iVue100 optical coherence tomographer, Oculus Keratograph and Nidek US-500 ultrasonographer. A Goldmann applanation tonometer was used to measure IOP. Data from only the right eyes were analysed because of high levels of interocular symmetry. A regression tree model was generated with the CART method and Pearson’s correlation coefficients were used to assess the relationships between the ocular variables.Results: The mean IOP for the entire sample was 14.63 mmHg ± 2.40 mmHg. The CART method selected three anterior segment variables in the regression tree model. Central corneal thickness was the most important variable with a cut-off value of 527 µm. The other important variables included average paracentral corneal thickness and axial anterior chamber depth. Corneal thickness measurements increased towards the periphery and were significantly correlated with IOP (r ≥ 0.50, p ≤ 0.001).Conclusion: The CART method identified the anterior segment variables that influenced IOP. Understanding the relationship between IOP and anterior segment variables may help to clinically identify patients with ocular risk factors associated with elevated IOPs.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Bu Ki Kim ◽  
Su Joung Mun ◽  
Young Hoon Yang ◽  
Ji Sun Kim ◽  
Jun Hyung Moon ◽  
...  

Abstract Background To compare the changes in the anterior segment after femtosecond laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) using a dual rotating Scheimpflug (DRS) analyzer (Galilei®; Ziemer Ophthalmology, Port, Switzerland). Methods A total of 218 eyes of 109 patients who underwent FS-LASIK or SMILE for myopic correction were retrospectively studied. Ninety-eight eyes of 49 patients who underwent FS-LASIK were compared to 120 eyes of 60 patients treated with SMILE. A DRS analyzer was used for preoperative and 6-month postoperative anterior segment analyses. Measured variables included the central corneal thickness (CCT), anterior chamber depth (ACD), anterior and posterior keratometry (K), anterior and posterior best-fit sphere radius, and maximum posterior elevation (MPE). Results After the procedure, the amount of CCT decrease was higher in the SMILE group than in the FS-LASIK group, but it was not statistically significant. The MPE was significantly increased after both procedures (p < 0.001 and p = 0.001 in the FS-LASIK and SMILE groups, respectively), with the amount of elevation being higher after FS-LASIK than after SMILE even though it was not statistically significant. And there was a significant change in the steep and average posterior K in the FS-LASIK group (p = 0.006 and 0.001, respectively), but not in the SMILE group. Conclusions Regarding changes in the MPE and posterior K, changes in the posterior corneal surface were greater after FS-LASIK than after SMILE. Trial registration The trial registration number: KCT0003628. Date of registration: 15 March 2019.


2021 ◽  
Author(s):  
Xu Zhang ◽  
Huixian Wang ◽  
Yuan Nie ◽  
Wenjing Li

Abstract Background: To evaluate and compare the changes in intraocular pressure and anterior eye segment biometrics,during and after wearing two types of commonly used swimming goggles.Methods: In a cross-sectional study, a total of 40 healthy adults aged between 18 and 60 years old were selected to wear two kinds of common swimming goggles (ocular socket and orbital goggles). Intraocular pressure and anterior segment biometry were evaluated before wearing, at 2 and 5 minutes of wearing, and at 5 minutes after removing the goggles. Intraocular pressure (IOP), corneal front keratometry values (K1, K2, Km), central corneal thickness (CCT), central anterior chamber depth (ACD), anterior chamber volume (ACV), and anterior chamber angle (ACA) were measured.Results: The IOP at 2 minutes (21.0±2.2 mmHg) and 5 minutes (21.2±2.3 mmHg) was significantly higher than before wearing goggles (17.7± 2.1 mmHg). The IOP after the goggles were removed and at 5 minutes after the goggles were removed was 18.4±2.3 mmHg and 17.7±2.1 mmHg, respectively. ACV, ACD, and ACA values all decreased while the googles were worn. After the goggles were removed, these changes gradually returned to baseline values, with no significant difference in the values before and after.Conclusion: This study proves that wearing orbital goggles can lead to an acute increase in IOP and a slight decrease in ACV, ACD, and ACA. However, once the goggles are removed, these indicators return to baseline levels, showing that wearing orbital goggles has no significant lasting effect on IOP and anterior segment parameters.


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