Analysis of Anterior Segment Parameters and Wavefront Aberrations of the Myopic Eyes Using Two Scheimpflug-based Devices: The Pentacam vs Sirius

Author(s):  
Ali Mirzajani ◽  
Rasoul Amini Vishteh ◽  
Rezvan Masroor

Abstract Purpose: To measurements, comparisons, and agreement of the anterior segment parameters and wavefront aberrations of the myopic eyes through the Pentacam and Sirius tomography systems. Methods: The Pentacam and Sirius were used to measure the corneal anterior segment tomography and wavefront aberrations of the myopic eyes with a mean age of 25.66±3.77 (range from 19 to 31 years).Various parameters such as the anterior keratometric reading of the flattest meridian K1, anterior K2, thinnest corneal thickness, corneal surface asphericity Q-value, anterior chamber depth, Root mean square (RMS) of higher-order aberrations, RMS of lower-order aberrations, and RMS of total aberrations were analyzed. Also, the agreement between the Pentacam and Sirius was assessed by calculating 95% limits of agreement and plotting the Bland–Altman graphs.Results: One eye of 99 myopic subjects (49 men, 50 women) aged 19 to 31 years was randomized and evaluated. All measured parameters of the Pentacam and Sirius tomography systems were statistically significant (p<0.001) in comparison with each other expect the mean values of K1, K2, and thinnest corneal thickness (p>0.05). The thinnest corneal thickness findings showed the poorest agreement (95 %limit of agreement from -8.71 to 24.21) and the greatest difference (mean difference: 7.75).Conclusions: The differences between the gained measurement results of the devices suggests that they should not be used interchangeably for corneal tomography imaging in clinical practice and surgery decision.

2016 ◽  
Vol 2016 ◽  
pp. 1-5
Author(s):  
Jinhai Huang ◽  
Weicong Lu ◽  
Giacomo Savini ◽  
Hao Chen ◽  
Chengfang Wang ◽  
...  

Purpose.To compare between a new optical biometer (AL-Scan, Nidek Co., Aichi, Japan) and an anterior segment optical coherence tomographer (Visante AS-OCT, Carl Zeiss Meditec, Dublin, USA) for measuring central corneal thickness (CCT), anterior chamber depth (ACD), and aqueous depth (AD).Methods.Sixty-three eyes of 63 normal subjects were examined with AL-Scan and Visante AS-OCT in this prospective study. One eye per subject was measured three times with both devices to record their CCT, ACD, and AD. All procedures were performed by the same operator. Agreement between the two devices was assessed using pairedt-tests, Bland-Altman plots, and 95% limits of agreement (LoA).Results.The mean CCT, ACD, and AD measured by AL-Scan were538.59±27.37 μm,3.70±0.30 mm, and3.16±0.30 mm, respectively. The mean values obtained by the Visante OCT were536.14±26.61 μm for CCT,3.71±0.29 mm for ACD, and3.17±0.29 mm for AD. The mean CCT by the AL-Scan was higher than that obtained by the Visante AS-OCT (difference =2.45±6.07 μm,P<0.05). The differences in ACD and AD measurements were not statistically significant. The 95% LoA of CCT, ACD, and AD were between −9.44 and 14.35 μm, −0.15 and 0.12 mm, and −0.15 and 0.12 mm, respectively.Conclusions.Since these two devices were comparable for measuring CCT, ACD, and AD, their results can be interchangeably used in the clinic.


Author(s):  
Alireza Khodabande ◽  
Massood Mohammadi ◽  
Hamid Riazi-Esfahani ◽  
Shahab Karami ◽  
Massood Mirghorbani ◽  
...  

Abstract Background To evaluate changes in anterior segment morphology on anterior segment optical coherence tomography (AS-OCT) following pars plana vitrectomy (PPV) without tamponade. Methods Patients who underwent PPV without tamponade for epiretinal membrane were evaluated. Eligible patients underwent intraocular pressure (IOP) measurement and AS-OCT preoperatively as well as 1 month and 6 months post-operatively. Anterior chamber width (ACW), anterior chamber depth (ACD), trabecular iris angle (TIA), angle opening distance at 500 and 750 µm (AOD), and trabecular iris space area at 500 and 750 µm (TISA) at four quadrants were recorded and analyzed. Additionally, the mean values of TIA (MTIA), AOD (MAOD), and TISA (MTISA) for each eye (mean of four quadrants) were analyzed. Results 23 patients completed the study. The mean age of participants was 56.4 ± 3.6 years of age and 13/23 (56%) were female. Mean IOP of patients was 18.1 ± 1.1, 18.3 ± 1.1, and 18.1 ± 1.2 preoperatively,1 month post-operatively, and 6 months post-operatively, respectively. (p = 0.83). No difference was detected post-operatively in measurements of ACW, ACD, MTIA, MAOD500, MAOD750, MTISA500, and MTISA750. Conclusion Pars plana vitrectomy without tamponade was not associated with changes in anterior chamber morphology.


2021 ◽  
Author(s):  
Qiong Lei ◽  
Haixia Tu ◽  
Xi Feng ◽  
Yong Wang

Abstract Background: To create an anterior chamber depth (ACD) regression model for adult cataract surgery candidates from China, and to evaluate the distribution of their ocular biometric parameters.Methods: The ocular biometric records of 28,709 right eyes of cataract surgery candidates who were treated at Aier Eye Hospitals in nine cities from 2018 to 2019 were retrospectively analyzed. All measurements were taken with IOLMaster 700. We included patients who were at least 40 years old and were diagnosed with cataract.Results: The mean age of the patients was 68.6 ± 11.0 years. The mean values recorded were as follows: axial length (AL), 24.17 ± 2.47 mm; mean keratometry (Km) value, 44.09 ± 3.25 D; corneal astigmatism (CA), 1.06 ± 0.98 D; ACD, 3.02 ± 0.45 mm; lens thickness (LT), 4.52 ± 0.45 mm; central corneal thickness (CCT), 0.534 ± 0.04 mm; and white to white (WTW) corneal diameter, 11.64 ± 0.46 mm. The proportion of patients with long axial length (AL >25 mm) decreased with age. ACD, LT, AL, Km, WTW, and age were correlated. In the multivariate regression analysis of ACD, which included LT, AL, WTW, sex, Km, CCT, and age, there was a reasonable prediction with adjusted R2 = 0.629.Conclusions: The results show that high myopes are inclined to schedule cataract surgery at a younger age. LT and AL were found to be important factors that affect ACD. This study provides reference data for cataract patients from China.


2021 ◽  
Vol 37 (3) ◽  
Author(s):  
Muhammad Suhail Sarwar ◽  
Sehrish Shahid ◽  
Muhammad Arslan Ashraf ◽  
Shaista Kanwal

Purpose:  To check inter observer reproducibility of axial ocular measurements i.e. central corneal thickness (CCT), anterior chamber depth (ACD), aqueous depth (AD), lens thickness (LT), anterior segment lens (ASL), vitreous length (VL) and axial length (AL) with non-contact HAAG-STRAIT biometer. Study Design:  Comparative Reproducibility Analysis. Place and Duration of Study:  College of ophthalmology and allied vision sciences (COAVS), Mayo Hospital, Lahore. Methods:  This study included 66 healthy students (132 eyes). Data was collected through self-designed proforma by 2 operators independently. SPSS 21 was used for data analysis. Interclass correlation was applied for agreement between the two readings. Interclass coefficient (ICC) value greater than 0.7 was considered as excellent correlation. Results:  The mean CCT, AD, ACD, LT, ASL, VL, and AL were 526.47 ± 35.72 µm and 526.47 ± 36.06 µm (ICC = 0.92); 2.93 ± 0.29 mm and 2.93 ± 0.29 mm (ICC = 0.81); 3.45 ± 0.30 mm and 3.46 ± 0.30 mm (ICC = 0.79); 3.58 ± 0.28 mm and 3.56 ± 0.22 mm (ICC = 0.76); 7.03 ± 0.30 mm and 7.02 ± 0.27 mm (ICC = 0.80); 16.56 ± 0.85 mm and 16.62 ± 0.81 mm (ICC = 0.72); and 23.59 ± 0.85 mm and 23.64 ± 0.87 mm (ICC: 0.76) of observer 1 and 2, respectively. Conclusion:  Non-contact Biometer (HAAG-STRAIT) has high inter-observer reproducibility with strong interclass coefficient of greater than 0.72. Key Words:  Biometry, Axial Length, Central Corneal Thickness, Anterior Chamber Depth.


2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
Mustafa Doğan ◽  
Mehmet Cem Sabaner ◽  
Mehmet Akif Erol

Purpose. To determine the effect of proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip on anterior segment parameters commonly used in routine ophthalmology practice. Methods. 115 healthy volunteers without any systemic or ocular disease were divided into two groups. 57 volunteers were in the proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture group, and 58 volunteers were in the fluorescein strip group. Measurements (CCT (central corneal thickness), topographic pupil diameter, AD (aqueous depth), ACV (anterior chamber volume), ICA (iridocorneal angle), LLD (limbus-limbus distance), and CV (corneal volume)) were taken before and at 1, 5, 15, and 30 minutes after application. Results. 59 (51.3%) participants were female, and 56 (48.7%) were male. The mean age of the drop application group was 26.88 ± 8.03, and the mean age of the strip application group was 26.33 ± 7.28. The mean CCT was 556 ± 32 μm before drop application and 569 ± 30 μm in the 1st minute, 560 ± 32 μm in the 5th minute, and 559 ± 31 μm in the 15th minute. The change was statistically significant (p<0.001, p=0.005, and p=0.013, resp.). Before the strip application, mean CCT was 552 ± 36 μm, while it increased to 556 ± 36 μm at the 1st minute, and this change was statistically significant (p=0.002). The mean CV before dropping was 59.29 ± 3.53 mm3 and 60.62 ± 3.53 mm3 at the 1st minute and 59.66 ± 3.70 mm3 at the 5th minute, which was statistically significant (p<0.001 and p=0.034). Mean topographic pupil diameters at the 1st, 5th, 15th, and 30th minute after application of drops and strips were not significantly changed compared to the preapplication values in the AD, ACV, ICA, and LLD measurements. Conclusions. Proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip application lead to a temporary change in CCT and CV of the anterior segment parameters. Anterior segment measurements with the Scheimpflug camera have to be done before topical fluorescein application.


2020 ◽  
Vol 12 ◽  
pp. 251584142094754
Author(s):  
Alper Halil Bayat ◽  
Gamze Karataş ◽  
Muhammet Mustafa Kurt ◽  
Mustafa Nuri Elçioğlu

Objectives: To evaluate the corneal effects of the intravitreal dexamethasone implantation using corneal topography and specular microscopy. Material and methods: 27 eyes of the 27 patients who received a single intravitreal dexamethasone implantation dose for diabetic macular edema were enrolled in this study. Sirius topography and EM-3000 specular microscopic examinations were performed at the initial examination (baseline), and then on the first day, during the first week, and 1 month after IDI. Changes in corneal parameters were investigated. Results: The mean age was 58.66 ± 6.59 years. 15 patients were men, and 12 were women. The mean disease duration was 12.2 ± 2.4 months, and mean glycosylated hemoglobin (HbA1c) was 7.2 ± 1.1. After dexamethasone injection, the mean central corneal thickness, endothelial cell density, and coefficient variation of cell area presented a statistically significant decrease ( p < 0.05). Anterior segment parameters, such as anterior chamber depth, iridocorneal angle, sim K1 and K2 keratometry, pupillary diameter, horizontal visible iris diameter, and corneal astigmatism did not change ( p > 0.05). Conclusion: Intravitreal dexamethasone implantation affects corneal endothelial cell structure but does not appear to affect corneal topography parameters.


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 ◽  
Vol 9 (1) ◽  
Author(s):  
Kumiko Kato ◽  
Mineo Kondo ◽  
Maki Takeuchi ◽  
Koji Hirano

Abstract To determine the parameters of the anterior segment of eyes that are significantly associated with the refractive error in healthy young Japanese university students. This was a cross-sectional observational study of 229 healthy Japanese university students (men: women,147:82) whose age ranged between 20 to 29 years. Univariate and multivariate linear regression analyses were performed to identify the factors that were significantly correlated with the refractive error. The independent variables included age, sex, axial length, anterior chamber depth, corneal diameter, curvature of anterior surface of cornea, and central corneal thickness. The mean refractive error (spherical equivalent) was −4.1 ± 2.7 diopters (D) with a range of −12.5 to +0.5 D, and the mean axial length was 25.4 ± 1.3 mm with a range of 22.4 to 29.0 mm. Pearson univariate correlation analysis found that the refractive error was significantly and negatively correlated with the axial length (R = −0.82, P < 0.001), deeper anterior chamber (R = −0.30, P < 0.001), and larger corneal diameter (R = −0.21, P = 0.001). Multiple regression analysis showed that the refractive error was significantly associated with a longer axial length (P < 0.001), a deeper anterior chamber (P < 0.001), and a flatter corneal curvature (P < 0.001).The biometric values of the anterior segment of the eyes should make the eye more hyperopic which would reduce the myopia-inducing lengthening of the axial length.


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.


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