scholarly journals Prediction of anterior chamber volume after implantation of posterior chamber phakic intraocular lens

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242434
Author(s):  
Yuki Takagi ◽  
Takashi Kojima ◽  
Tomoya Nishida ◽  
Tomoaki Nakamura ◽  
Kazuo Ichikawa
Keyword(s):  
Anterior Chamber ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Absolute Error ◽  
Prediction Equation ◽  
Stepwise Multiple Regression ◽  
Posterior Chamber ◽  
Implantable Collamer Lens ◽  
Chamber Volume ◽  
Anterior Chamber Volume

Purpose To predict the anterior chamber volume (ACV) after implantable collamer lens (ICL) implantation based on ICL size and parameters of anterior segment optical coherence tomography (AS-OCT). Design Retrospective study. Methods This study included 222 eyes of 222 patients who underwent ICL implantation at Nagoya Eye Clinic. The patients were divided into two groups: prediction group, for creating the prediction equation (148 eyes, mean age: 32.11 ± 8.04 years), and verification group, for verifying the equation (74 eyes, mean age: 33.03 ± 6.74 years). The angle opening distance (AOD), anterior chamber width (ACW), ACV, anterior chamber depth, lens vault, angle-to-angle distance, angle recess area, and trabecular iris space area were calculated using AS-OCT. A stepwise multiple regression analysis was performed. After the creation of the prediction equation, its accuracy was verified in the verification group. Results The ACV, AOD750, ACW, and ICL size were selected as explanatory variables to predict postoperative ACV. Mean predicted (114.2 ± 21.83 mm3) and actual postoperative ACVs (116.1 ± 25.41 mm3) were not significantly different (P = 0.269); absolute error was 10.59 ± 9.13 mm3. In addition, there was high correlation between actual and predictive ACV (adjusted R2 = 0.6996, p < 0.0001). Bland-Altman plot revealed that there was no addition or proportional error between predicted and actual postoperative ACV. Conclusion Postoperative ACV was accurately predicted using AS-OCT parameters and ICL size. This prediction equation may be useful for making decisions regarding ICL size.

scholarly journals Changes in Anterior Segment Morphology of Iris Bombe before and after Laser Peripheral Iridotomy in Patients with Uveitic Secondary Glaucoma

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Wakako Ikegawa ◽  
Takashi Suzuki ◽  
Koji Namiguchi ◽  
Shiro Mizoue ◽  
Atsushi Shiraishi ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Anterior Chamber Angle ◽  
Laser Peripheral Iridotomy ◽  
Chamber Volume ◽  
Anterior Chamber Volume ◽  
Before And After ◽  
The Mean ◽  
Peripheral Iridotomy

Purpose. To quantify changes in anterior segment (AS) parameters after laser peripheral iridotomy (LPI) using AS-optical coherence tomography (OCT) of iris bombe. Method. AS images of eight eyes were captured before and after iris bombe and more than 2 weeks after LPI (post-LPI) using AS-OCT. We compared the following AS parameters: anterior chamber depth (ACD), anterior chamber volume (ACV), iris curvature (IC), iris thickness at 500 μm from the scleral spur (IT-1) in the middle between the iris root and pupillary margin (IT-2) and 500 μm from the pupillary margin (IT-3) to the anterior chamber angle (ACA) (angle opening distance [AOD750]), and trabecular iris space area. Results. Mean IT-1 and IT-3, but not IT-2, were lower after iris bombe (IT-1, P=0.001; IT-2, P=0.081; and IT-3, P=0.001). There were no significant differences between ACD at pre-LPI and before iris bombe (P=0.096). The mean ACV and AOD750 of iris bombe increased at post-LPI (ACV, P<0.01, and AOD750, P<0.05). The mean IT-1, IT-2, and IT-3 increased at post-LPI (all, P≤0.01). IC decreased at post-LPI (P<0.001), and ACD at post-LPI did not change. Conclusions. The iris extends and becomes thinner during iris bombe. LPI during bombe decreases the IC and increases the ACV and ACA.

Association of anterior segment parameters and 5-year incident narrow angles: findings from an older Chinese population

2020 ◽  
pp. bjophthalmol-2020-315852
Author(s):  
Yu Jiang ◽  
Wei Wang ◽  
Lanhua Wang ◽  
Mingguang He
Keyword(s):  
Anterior Chamber ◽  
Multiple Logistic Regression Analysis ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Narrow Angle ◽  
Chamber Volume ◽  
Anterior Chamber Volume ◽  
Oct Imaging ◽  
Older Chinese ◽  
Analysis Models

PurposeTo assess the association of anterior segment optical coherence tomography (AS-OCT) parameters and 5-year incident narrow angle in China.MethodsThis was a prospective cohort study of people aged 50 and older residing in Liwan District, Guangzhou, China. Random clustering sampling was used to identify adults aged 50 years and older in Liwan District, Guangzhou. In 2008 and 2013, this study was repeated and added AS-OCT imaging under dark and light conditions. Customised software (ZAAP) was used to analyse horizontal AS-OCT scans. Angle opening distance (AOD), trabecular iris space area (TISA), anterior chamber volume (ACV) and maximal iris thickness (ITM) were measured. Multiple logistic regression analysis models were used to investigate the associations of the final angle status with baseline AS-OCT parameters. ORs and 95% CIs were calculated.ResultsOf the 220 subjects with eligible AS-OCT images and gonioscopic results in 2008, the response rate was 77.3%. A total of 27 (15.9%) subjects developed narrow angles and 143 (84.1%) had open angles on gonioscopy in 2013. Subjects developed narrow angles had greater spherical equivalent and shallower anterior chamber depth, smaller angle parameters, thicker IT750 and ITM, smaller anterior chamber parameters, greater lens vault, and smaller dynamic parameters (ΔITM, ΔACA, ΔACV) at baseline. After adjusting confounders, the predictors of incident narrow angles included smaller AOD750, TISA750, ΔACA and greater ITM, ΔIarea.ConclusionsIncident narrow angles were associated with smaller anterior ocular dimensions, thicker iris and smaller light-to-dark changes at baseline. These findings can help in early diagnosis in this population.

scholarly journals Two-Year Outcomes of Visian Implantable Collamer Lens with a Central Hole for Correcting High Myopia

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Zhipeng Yan ◽  
Huamao Miao ◽  
Feng Zhao ◽  
Xiaoying Wang ◽  
Xun Chen ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Anterior Chamber ◽  
High Myopia ◽  
Imaging System ◽  
Anterior Chamber Depth ◽  
Central Hole ◽  
Implantable Collamer Lens ◽  
Chamber Volume ◽  
Anterior Chamber Volume ◽  
Icl V4c

Purpose. To investigate two-year outcomes of Visian Implantable Collamer Lens with a central hole (ICL V4c) implantation for correcting high myopia.Methods. Sixty-one eyes of 32 patients went through ICL V4c implantation. Safety, efficacy, predictability, and intraocular pressure were evaluated 2 years postoperatively. Anterior chamber volume (ACV), anterior chamber depth (ACD), anterior chamber angle width (ACAW), and vault were measured using a Scheimpflug tomography imaging system.Results. At 2 years, the spherical equivalent refraction decreased from preoperative −14.62 ± 4.29 D to −0.90 ± 0.95 D, with 79% of the eyes within ±0.50 D and 98% within ±1.00 D of the intended correction. The efficacy index was 1.03 ± 0.23, and the safety index was 1.24 ± 0.26. Corrected distance visual acuity (CDVA) remained unchanged in 23% of the eyes, 75% gained one or more lines of CDVA, and 2% lost one line. The ACV, ACD, and ACAW, respectively, decreased from 193.28 ± 29.15 mm3, 3.15 ± 0.23 mm, and 36.51 ± 6.54 degree to 112.48 ± 17.01 mm3, 2.99 ± 0.23 mm, and 22.54 ± 5.27 degree (p=0.0008,  0.008,  and  0.0003, resp.). Intraocular pressure was 15.39 ± 2.88 mmHg before surgery and was 15.86 ± 4.11 mmHg at 2 years (p=0.11).Conclusion. Implantation of ICL V4c is a safe, effective, and predictable procedure for correcting high myopia. Reduction of anterior chamber space after surgery did not induce intraocular pressure increase during the 2-year follow-up.

scholarly journals Pupil Size Associated with the Largest Iris Volume in Normal Chinese Eyes

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Shuning Li ◽  
Jing Jiang ◽  
Yiquan Yang ◽  
Gewei Wu ◽  
Shi-Ming Li ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Pupil Size ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Quadratic Equation ◽  
Swept Source ◽  
Chamber Volume ◽  
Anterior Chamber Volume ◽  
The Relationship ◽  
Pupillary Size

Background. To determine the range of pupil size that has the largest iris volume in normal eyes. Methods. 31 healthy adult Chinese volunteers underwent swept-source anterior segment OCT examination in both eyes. Pilocarpine 1% was instilled in a randomly selected eye (eye with induced miosis (ME)) of each participant to obtain iris volume (IV) measurements over a range of pupil sizes. OCT was performed prior to and one hour after pilocarpine in both ME and fellow eye (FE). Iris volume (IV), anterior chamber volume (ACV), anterior chamber depth (ACD), and pupil size (PS) were recorded. A scatter plot was used to depict the association between each pupil size and IV. Results. The pupillary sizes for which IV was recorded in ME and FE ranged from 1.161 mm to 6.665 mm. The mean IV increased with miosis in both ME and FE; in 13 eyes, IV decreased with a decrease in pupillary size. PS between 3.812 and 6.665 mm was associated with an increase in IV, while PS between 3.159 and 5.54 mm was associated with a decrease. The relationship between PS and IV was in the shape of a downward parabola and was modeled using a quadratic equation (y = −1.3121x2 + 8.8429x + 16.423, R2 = 0.26886). The largest IV occurred at PS between 3 and 4 mm. Conclusions. The relationship between PS and IV in this study was in the shape of a downward parabola. The largest IV was recorded at a pupillary size between 3 and 4 mm. This trial is registered with ChiCTR-ROC-17013572.

scholarly journals Measurement of and Factors Associated with the Anterior Chamber Volume in Healthy Chinese Adults

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Yuan Zong ◽  
Qian Xu ◽  
Chunhui Jiang ◽  
Haohao Zhu ◽  
Jian Yu ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Chinese Adults ◽  
Factors Associated ◽  
Chamber Volume ◽  
Significant Difference ◽  
Anterior Chamber Volume ◽  
Anterior Segment Parameters ◽  
Healthy Chinese

Purpose. To measure the anterior chamber volume (ACV) and determine factors associated with the ACV in healthy Chinese adults.Methods. In this cross-sectional study, we used swept-source optical coherence tomography (SS-OCT) to measure ACV and other anterior segment parameters. Factors associated with ACV were also determined.Results. A total of 313 healthy Chinese adults were enrolled. The anterior segment parameters, including ACV, could be measured by SS-OCT with excellent repeatability and reproducibility. There was a significant difference between the horizontal and vertical anterior chamber widths (ACW) (P<0.05), with a mean difference of 390 μm. The ACV (mean153.83±32.42 mm3) was correlated with most of the anterior segment parameters, especially anterior chamber depth (ACD), which accounted for about 85% of the variation of ACV. Most of the anterior segment parameters were significantly correlated with age, and the relative changes in ACV and ACD were greatest in subjects aged 41–50 years.Conclusion. ACV was correlated with most of the anterior segment parameters measured in this study, particularly ACD. The relatively large difference between horizontal and vertical ACW suggests that the ACV could and should be measured using multiple OCT scans.

scholarly journals Correlation between intraoperative and postoperative vaulting of the EVO implantable Collamer lens: a retrospective study of real-time observations of vaulting using the RESCAN 700 system

2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Nian Guan ◽  
Xiao-Nong Zhang ◽  
Wan-Jun Zhang
Keyword(s):  
Retrospective Study ◽  
Anterior Chamber ◽  
Multivariable Analysis ◽  
Anterior Chamber Depth ◽  
Crystalline Lens ◽  
Implantable Collamer Lens ◽  
Chamber Volume ◽  
Anterior Chamber Volume ◽  
Intraoperative Optical Coherence Tomography ◽  
Corneal Endothelial Cell Density

Abstract Background Implantable Collamer lens (ICL) vaulting is one of the most important parameters for the safety, aqueous humor circulation, and lens transparency after ICL implantation. This study aimed to investigate the factors associated with the actual vaulting after refractive EVO-ICL surgery. Methods This retrospective study included patients who underwent EVO-ICL surgery at a tertiary eye hospital between October and December 2019. A RESCAN 700 was used for the intraoperative and CIRRUS HD-OCT was used for postoperative observation of vaulting. Subjective and objective refractions, anterior ocular segment, corneal morphology, intraocular pressure (IOP), anterior chamber volume (ACV), crystalline lens rise (CLR), white-to-white distance (WTW), anterior chamber depth (ACD), axial length, corneal endothelial cell density (ECD), and fundoscopy were examined. A multivariable analysis was performed to determine the factors independently associated with 1-month postoperative vaulting. Results Fifty-one patients (102 eyes) were included. Compared with the eyes with normal vaulting, those with high vaulting had higher preoperative diopter values (P = 0.039), lower preoperative corrected visual acuity (P = 0.006), lower preoperative IOP (P = 0.029), higher preoperative ACD (P = 0.004), lower preoperative CLR (P = 0.046), higher ICL spherical equivalent (P = 0.030), higher intraoperative vaulting (P < 0.001), and lower IOP at 1 month (P = 0.045). The multivariable analysis showed that the only factor independently associated with high vaulting at 1 month after surgery was the intraoperative vaulting value (odds ratio = 1.005, 95% confidence interval: 1.002–1.007, P < 0.001). The intraoperative and 1-month postoperative vaulting values were positively correlated (R2 = 0.562). Conclusions The RESCAN700 system can be used to perform intraoperative optical coherence tomography to predict the vaulting value of ICL at 1 month.

scholarly journals Refractive Error and Biometrics of Anterior Segment of Eyes of Myopic Teenagers

2020 ◽  
Author(s):  
Huimin Ge ◽  
Shanshan Xu ◽  
Yanzhi Yan ◽  
Qin Jiang
Keyword(s):  
Anterior Chamber ◽  
Refractive Error ◽  
Age Groups ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Case Series ◽  
Corneal Surface ◽  
Chamber Volume ◽  
Anterior Chamber Volume ◽  
The Impact

Abstract Background: To investigate the impact of refractive error and corneal parameters on myopic teenagers by using Pentacam and IOL Master 700. Methods: Retrospective observational case series of 505 eyes from 268 children from 7 to 19 years old presenting with myopia. Clinical course, slit lamp photographs and pentacam and IOL Master 700 findings were the main outcomes. Results: Assessment of the tomographic, topographic of corneal parameters of myopic children without any interventions revealed no statistically significant changes in terms of age based on sex. The mean Rf, Rs, K1 and K2 values of anterior and posterior corneal surface were 7.98±0.24mm, 7.73±0.30mm, 42.38±1.86 degrees, 43.55±1.91 degrees, 6.60±0.25mm, 6.21±0.26mm, -6.07±0.23 degrees, -6.42±0.65 degrees. Boys had higher Rf and Rs, but smaller in K1 and K2 than girls (P<0.05) of both anterior and posterior corneal surface. The Anterior chamber volume (ACV) had significant differences between sex (P<0.05). The Rf, K1 of anterior corneal surface did not show significantly different between ages, however, teenagers only in 7 to 9 age group increased significantly than 13 to 15-year-old group (P=0.031). Meanwhile, the Anterior chamber depth (ACD), Anterior chamber volume (ACV), Pupil diameter (PD), Spherical equivalent (SE) and Axial length (AL) had increasingly differenced in different age groups (P=0.002, 0.002, 0.036, 0.044, 0.002, <0.001). Model performance using p< 0.05 parameters as the predictive factors. SE=3.391+0.08×Age+2.307×Rs-0.094×ACD-0.001×ACV-0.951×AL. Conclusions: Our findings may suggest a physiological nature for ocular changes during the development that may elucidate the special points during the process of myopia of adolescents. We also imitate a formula based on our data which may help to evaluate the myopia of children and the prognosis in clinic.Our research conducted retrospectively registered.

Intraocular Pressure Spikes after Aflibercept Intravitreal Injections

2016 ◽  
Vol 236 (1) ◽  
pp. 43-47 ◽  
Author(s):  
Hussam El Chehab ◽  
Emilie Agard ◽  
Aurélie Russo ◽  
Ygal Boujnah ◽  
Corinne Dot
Keyword(s):  
Intraocular Pressure ◽  
Anterior Chamber ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Angle Closure ◽  
Iridocorneal Angle ◽  
Chamber Volume ◽  
Short Period ◽  
Anterior Chamber Volume ◽  
Acute Increase

The objective of this study was to assess the intraocular pressure (IOP) as well as the anatomical modifications of the anterior segment following an aflibercept injection. Patients underwent an aflibercept intravitreal injection (IVI) (0.05 ml) with a 30.5-gauge needle and an antireflux system. IOP was assessed before injection (T0), immediately after (T1), and 5 min (T5), 15 min (T15), and 45 min (T45) after the IVI. Before the IVI and immediately after the T1 measurement, a PENTACAM® acquisition was used to evaluate the anterior chamber parameters (anterior chamber volume, depth and measure of the iridocorneal angle). At T0, IOP was 12.9 ± 1.3 mm Hg. IOP significantly increased after IVI (42.7 ± 3 mm Hg, p < 0.001). IOP returned to baseline at T45 (13.0 ± 1.2 mm Hg, p = 0.877). Anterior chamber volume decreased after IVI (160.6 vs. 168.3 mm3, p = 0.002). No significant changes were found for iridocorneal angle and anterior chamber depth. Aflibercept IVI causes an acute increase in IOP over a short period without iridocorneal angle closure.

​Short-term changes in and preoperative factors affecting vaulting after posterior chamber phakic Implantable Collamer Lens implantation

2020 ◽  
Author(s):  
Qiujian Zhu ◽  
Wen-Jing Chen ◽  
Wei-Jian Zhu ◽  
Hai-Xiang Xiao ◽  
Man-Hui Zhu ◽  
...  
Keyword(s):  
Multiple Regression ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
Crystalline Lens ◽  
Stepwise Multiple Regression ◽  
Multiple Regression Equation ◽  
Posterior Chamber ◽  
Key Factors ◽  
Implantable Collamer Lens ◽  
Factors Affecting

Abstract Background: To describe the very early changes in vault in the first month after Implantable Collamer Lens (ICL) implantation and to evaluate the effect of preoperative biometric factors on vault.Methods: A total of 83 eyes from 83 subjects with complete data who met follow-up requirements were recruited in this retrospective study between May 2019 and March 2020. We quantitatively assessed postoperative vault at 2 hours, 1 day, 1 week, and 1 month following implantation. Associations between postoperative vault and age, ICL size, spherical equivalent (SE), axial length (AL), central corneal thickness (CCT), flat K, steep K, mean K, anterior chamber depth (ACD), crystalline lens thickness (LT), white-to-white (WTW) diameter obtained by three devices, horizontal and vertical sulcus-to-sulcus (STS) diameter, bright and dark pupil sizes (BPS and DPS) and DPS-BPS were investigated using Spearman’s correlation analysis and stepwise multiple regression analysis.Results: The mean vault values at 2 hours, 1 day, 1 week, and 1 month after ICL implantation were 672.05 ± 30.72, 389.15 ± 28.33, 517.23 ± 30.76 and 530.12 ± 30.22 μm, respectively. There were significant differences in vault values between 2 hours, 1 day and 1 week after the operation. ICL size (β = 0.942; p < 0.001), followed by horizontal STS (β = -0.517; p < 0.001), crystalline LT (β = -0.376; p < 0.001) and vertical STS (β = -0.257; p = 0.017), significantly influenced vault at 1 month after the operation. The multiple regression equation was expressed as follows: central vault (μm) = -1369.05+ 657.121 × ICL size- 287.408 × horizontal STS - 432.497 × crystalline LT - 137.33 × vertical STS (adjusted R2 = 0.643).Conclusions: After ICL implantation, vault decreased and then increased, but it did not return to the vault value at 2 hours after surgery. ICL size, horizontal and vertical STS and crystalline LT were key factors for predicting postoperative vaulting.

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