Increase In Anterior Chamber Depth Research Articles

Evaluation of early period changes in intraocular pressure, ocular biometry and anterior segment after upper eyelid blepharoplasty.

To investigate the acute effects of upper eyelid blepharoplasty on intraocular pressure (IOP) and ocular biometric parameters. This prospective cross sectional study examined the eyes of 49 patients with dermatochalasis. Following a detailed ophthalmological examination, corneal topography was used to evaluate the eyes mesopic and photopic pupil diameter, anterior chamber depth, and corneal astigmatism on the day of surgery and on days first and seventh postoperatively. Ocular biometry was used to assess axial length and intraocular lens power. Goldmann applanation tonometry was used to measure intraocular pressure. Forty-nine eyes (26 males and 23 females) of 49 patients aged between 44 and 76years (mean 61 ± 7.9) were included in our study. The mean anterior chamber depth (ACD) was 2.90 ± 0.37mm preoperatively, 3.00 ± 0.29mm at postoperative day first, and 3.04 ± 0.29mm at postoperative day seventh, and the increase in anterior chamber depth was statistically significant (p < 0.001). The mean astigmatism values were measured as preoperative 0.73 ± 0.69 D, postoperative first day 0.93 ± 0.81 D, and postoperative seventh day 1.26 ± 0.90 D. The increase in astigmatism values was statistically significant (p < 0.001).The mean pupil diameter measurements in the mesopic environment were 4.20 ± 0.61mm preoperatively, 4.40 ± 0.59mm on the first postoperative day, and 4.39 ± 0.57mm on the seventh postoperative day, and there was a statistically significant difference between the three measurements (p = 0.03). The mean IOP measurements of the patients were 15.91 ± 3.51mmHg preoperatively, 16.81 ± 3.36mmHg on the first postoperative day, and 16.97 ± 3.13mmHg on the seventh postoperative day. The increase between these three measurements was statistically significant (p = 0.013). This study includes important insights into the potential acute phase impact of blepharoplasty surgery on ocular findings. Patients undergoing upper eyelid surgery should be informed about the possible change in ocular biometric parameters, intraocular pressure, and pupil diameter.

Comparison of Lens Extraction Versus Laser Iridotomy on Anterior Segment, Choroid, and Intraocular Pressure in Primary Angle Closure Using Machine Learning.

Treatment strategy of primary angle closure (PAC) is not clear due to the large number of clinical and anatomic-topographic parameters in PAC, influencing the treatment algorithm. Using the machine learning method DD-SIMCA, we justify the expediency of early lens extraction (LE) in PAC. To compare the anatomic and functional efficacy of LE and laser peripheral iridotomy (LPI) in patients with PAC using Machine Learning. This prospective study included 120 patients aged 41-80 years: 60 eyes with PAC, 30 with PAC suspects, and 30 with healthy eyes (control). Thirty PAC eyes with intraocular pressure (IOP) up to 30 mm Hg were treated using LE with intraocular lens implantation and 30 eyes with LPI. All subjects underwent Swept Source optical coherence tomography. We analyzed 35 parameters of each eye including the lens vault, the choroidal thickness, the anterior chamber angle, and iris specifications such as iris curvature. Considering the correlations between them, the machine learning method DD-SIMCA 1-class classification was applied: the proximity of each sample to the target class (control) was characterized by the total distance to it. After LE, IOP was significantly lower than after LPI ( P =0). Every third eye with PAC after LE reached the target class: specificity according to DD-SIMCA equals 0.67. This was not observed for the eyes after LPI: specificity equals 1.0. After LE, all parameters of the anterior chamber angle did not differ from the control (all P >0.05). After LPI, there was an increase in anterior chamber depth ( P =0) and a decrease in lens vault ( P =0), but results comparable to the control were achieved only for iris curvature ( P =1.000). The efficacy of LE in PAC is higher than LPI due to the better postoperative anterior chamber topography and lower IOP. This study lends further clinical and anatomic support to the emerging notion of LE as an effective treatment for PAC.

Correlation between corneal refractive power and anterior chamber morphology in age-related cataract patients with shallow anterior chambers

Objective: To investigate the relationship between corneal refractive power and anterior chamber parameters in age-related cataract patients with normal axial lengths and shallow anterior chambers. Methods: Retrospective case series study. Clinical data of 627 age-related cataract patients (627 eyes) with axial lengths between 22 mm and 24 mm and anterior chamber depths less than 2.20 mm treated in the Department of Ophthalmology of Peking University International Hospital from June 2018 to October 2021 were selected. There were 215 male patients and 412 female patients, with an average age of (75±10) years. According to the average corneal refractive power, eyes were divided into groups of keratometry (K)<42 diopters (D) (50 eyes), 42 D ≤K<45 D (398 eyes) and K ≥45 D (179 eyes). Axial length, anterior chamber depth, corneal diameter, anterior chamber volume and anterior chamber angle of 3 groups were recorded, and Spearman correlation analysis was used to analyze the correlation between parameters. The differences of parameters among different groups were compared by one-way analysis of variance or Kruskal-Wallis test, and multiple or pairwise comparisons using LSD-t test or Mann-Whitney U test. Results: There was a negative correlation between axial length and corneal refractive power in 627 eyes (r=-0.62, P<0.001). Corneal refractive power was positively correlated with anterior chamber depth (r=0.26, P=0.006), while in the K≥45 D group, corneal refractive power was also positively correlated with anterior chamber depth (r=0.23, P=0.025). Anterior chamber depth [M (Q1,Q3)] was 1.77 (1.64, 1.90) mm in the K<42 D group, 1.85 (1.70, 2.14) mm in the 42 D≤K<45 D group and 2.02 (1.81, 2.18) mm in the K≥45 D group. Multiple comparisons showed that there were significant differences in anterior chamber depth between the K<42 D group and the K≥45 D group, between the 42 D≤K<45 D group and the K≥45 D group (U=14 372.00, 18 226.00; both P<0.05). There was a negative correlation between corneal refractive power and corneal diameter in 627 eyes (r=-0.52,P<0.001), while in the 42 D≤K<45 D group and the K≥45 D group, corneal refractive power were also negatively correlated with corneal diameter (r=-0.20, -0.28; both P<0.05). Corneal diameter was (11.77±0.43) mm in the K<42 D group, (11.24±0.35) mm in the 42 D≤K<45 D group and (10.90±0.33) mm in the K≥45 D group, while there were significant differences in multiple comparisons (t=1.92, 2.96, 2.01; all P<0.05). There was no correlation between corneal refractive power and anterior chamber volume, or between corneal refractive power and anterior chamber angle in 627 eyes (all P>0.05). There was no significant difference both in anterior chamber volume and in anterior chamber angle among 3 groups (all P>0.05). Conclusion: For age-related cataract patients with normal axial lengths and shallow anterior chambers, the anterior chamber depth increase and the corneal diameter decrease with the increase of corneal refractive power, but there is no significant change in anterior chamber volume and anterior chamber angle.

Eclipse solaire ou ectopie du cristallin?

Ectopia lentis is defined as an acquired or hereditary malposition of the crystalline lens due to a zonular deficiency. It can be caused by a trauma or secondary to an underlying systemic disease, such as Marfan syndrome, Weill-Marchesani syndrome and homocystinuria. Marfan Syndrome (MFS) is a disease of the connective tissue mainly affecting the ocular, cardiovascular and skeletal system. Up to 80% of patients with Marfan syndrome develop ectopia lentis, 50% of which occurs before the age of 5. Lens displacement is usually bilateral and symmetrical, and frequently occurs superotemporally. We here report the case of a 17-year-old girl born to consanguineous parents. She presented with behavioral disorders and school problems reported by her parents. On general examination, she was tall for her age and had long, thin fingers. Clinical examination showed visual acuity 2/10 and good pupillary light reflex; the examination of the anterior segment objectified clear cornea, with an increase in anterior chamber depth and bilateral ectopia lentis in the nasal area. Fundus examination was normal. Etiological research didn’t uncover causal effects. The patient underwent phacophagia with implantation of an iris-fixated implant and skin biopsy aimed to confirm the diagnosis of Marfan syndrome.

Changes in the anterior segment after cataract surgery and intraocular lens implantation using ultrasonic biomicroscopy

ObjectiveTo study changes in the anterior segment after cataract surgery and intraocular lens implantation by means of ultrasonic biomicroscopy.BackgroundCataract surgery is the only treatment for cataract with high success rate in restoring sight. Ultrasonic biomicroscopy is a noninvasive modality that allows for the real-time visualization of anterior-segment tissues with microscopic resolution and provides information about the size and the nature of the lesion, permitting a presumptive diagnosis.Patients and methodsA prospective nonrandomized and comparative study was conducted on 20 eyes of 20 patients aged 43–72 years who attended the outpatient clinic of Menoufia University Hospital and Zagazig University Hospital in the period from August 2020 to January 2021. Full history, routine, and a thorough ophthalmic examination were done. All surgeries were performed under local anesthesia with or without sedation.ResultsA total of 20 patients underwent phacoemulsification included in our study, most of them aged from 60 to 69 years old, 11 (55%) males and nine (45%) females. The mean increase in anterior-chamber depth is 0.79 mm, 28.11% deeper than before surgery. There is a statistically significant difference between pre and post according to anterior-chamber angle with P value less than 0.001. The mean increase in anterior-chamber angle is 8.61°, which represents 27.67% increase of preoperative measurement. There is a high statistically significant difference between pre and post according to angle-opening distance 500 μm with P value less than 0.001. The mean increase in angle-opening distance was 0.09 mm, significantly increasing to 21.42% of preoperative value.ConclusionsThere are some positional changes in the anterior-segment structures after cataract surgery. The quantitative changes in anterior-chamber depth and angle may be determined by ultrasound biomicroscopy. The anterior chamber deepens and its angle widens that significantly increased after cataract surgery. Ultrasound biomicroscopy provides quantitative values of angle parameters and maybe of clinical significance in eyes with narrow angle. Numerical values that we detected in our study could provide an anatomical reference for further studies. Based on our findings, we recommend for further studies on larger sample size and on a large geographical scale to emphasize our conclusion.

Role of Preoperative Nd:YAG Laser Anterior Capsulotomy in Mature Intumescent Cataracts.

The aim of this study was to examine the role of preoperative Nd:YAG laser anterior capsulotomy in preventing intraoperative complications in mature intumescent cataracts. A prospective, interventional, observational study. A total of 52 eyes of 52 patients were selected in this prospective study. Preoperative Nd:YAG laser anterior capsulotomy was performed in all eyes with 1 shot of 1.2 mJ and a gush of the liquified cortex was noted. Anterior chamber depth was measured using anterior segment optical coherence tomography and intraocular pressure using Goldmann applanation tonometer were measured pre- and post-laser. Intraoperative complications and surgeon's operative comfort were noted. There was a mean increase in anterior chamber depth by 0.24 mm and a mean decrease in intraocular pressure by 1.61 mm Hg postlaser. No intraoperative complications were noted except for capsulorhexis extension in 1 eye (1.92%). The surgeon experienced a good control while performing the capsulorhexis and overall an uneventful surgery. Preoperative Nd:YAG laser anterior capsulotomy is a safe and effective technique in reducing intralenticular pressure and avoiding intraoperative complications in mature intumescent cataracts.

Could anatomical changes occurring with cataract surgery have a clinically significant effect on effective intraocular lens position?

To assess if the calculation of the effective lens position (ELP) of two different monofocal intraocular lenses (IOLs) could be optimized by considering the potential anatomical changes occurring after cataract surgery. Prospective, descriptive, single-center study involving 472 eyes of 280 subjects (mean age 73.5years) undergoing cataract surgery that were divided into two groups according to the IOL implanted: group 1330 eyes with AcrySof IQ SN60WF (Alcon), and group 2142 eyes with Akreos MI60L (Bausch + Lomb). Refractive and biometric changes were evaluated during a period of 6-month follow-up with an optical biometer (considering potential measurement artifacts). Comparison of ELP estimated with the SRK-T formula (ELPSRK-T) and ELP calculated considering clinical real data was made (ELPAXL-corrected clinical). Besides significant changes in refraction (p ≤ 0.020), a significant increase in anterior chamber depth (ACD) (p < 0.001) and a significant reduction in the axial length (AXL) (p < 0.001) were detected at 1month after surgery. Mean 1-month postoperative AXL change was - 0.08 ± 0.06 and - 0.10 ± 0.11mm in groups 1 and 2, respectively (p = 0.001), with no significant changes afterward. Mean difference between ELPSRK-T and ELPAXL-corrected clinical was 0.17 ± 0.39 and - 0.23 ± 0.43mm in groups 1 and 2, respectively (p < 0.001). A strong and statistically significant correlation of these differences with the prediction refractive error was found in both groups (group 1, r = - 0.723; group 2, r = - 0.819; p < 0.001). The estimation of ELP using the SRK-T formula for the two IOLs evaluated may be optimized considering biometric changes with surgery, helping to understand better some problems of refractive unpredictability.

Effect of body stature on refraction and ocular biometry in Chinese young adults: The Anyang University Students Eye Study

ABSTRACT Clinical relevance Large‐scale data on the association between body stature with biometry parameters and refraction in young adults facilitates an understanding of myopia development. Taller persons have eyes with more negative refractions, longer axial lengths, deeper anterior chambers, flatter corneas, and higher axial length‐corneal radius ratio. Background To determine the relationship between body stature with ocular biometry and refraction in young adults. Methods This was a cross‐sectional university‐based study of 16‐ to 26‐year‐old students in China. Cycloplegic refraction and corneal curvature were measured using an autorefractor. Ocular parameters, including axial length, anterior chamber depth and lens thickness, were measured using a Lenstar LS900. Data on height and weight were acquired from an annual standardised physical examination and body mass index was calculated. Results Of 7,971 participants examined in the school clinics, 5,657 (71.0 per cent) were available in the analysis. After adjusting for age, gender, parental myopia, time outdoors, near work and weight, each centimetre of height increase was associated with more negative refraction of −0.023-D, a 0.032-mm increase in axial length, a 0.003-mm increase in anterior chamber depth, a 0.008-mm increase in corneal curvature, and a 0.001 increase in axial length‐corneal radius ratio. With regard to weight, a 1-kg heavier person was more likely to have less negative refraction of 0.011-D, a 0.001-mm increase in anterior chamber depth and a 0.002-mm increase in corneal curvature. A similar pattern of significant associations was also found in body mass index. Conclusion Taller, young adults tended to have longer eyes, deeper anterior chambers, flatter corneas, higher axial length‐corneal radius ratio, and more negative refraction, adjusted for potential confounders. In contrast, heavier and higher body mass index persons are more hyperopic. The differences in stature may partially explain the variation in refraction and ocular biometric parameters.

Changes in Intraocular Pressure and Angle Structure after Dilation in Primary Angle-Closure Suspects with Visually Significant Cataract

To evaluate the safety of pupillary dilation in primary angle-closure suspects (PACS) with concurrent visually significant cataract (VSC), to identify risk factors associated with elevated intraocular pressure (IOP), and to describe changes in anterior segment anatomy after pupillary dilation. Prospective study. Patients with PACS and VSC and no prior laser or intraocular surgery were recruited. Visually significant cataract was defined as best-corrected visual acuity ≤ 20/40 due to cataract. Subjects' eyes were dilated with 0.5% tropicamide and 0.5% phenylephrine hydrochloride. A standardized eye examination, biometry, and swept-source OCT (SS-OCT) were performed before dilation. Intraocular pressure and SS-OCT were repeated 1, 4, and 6 hours postdilation (PDH1, PDH4, and PDH6, respectively). All parameters were compared between time points before and after dilation using paired t test. Linear regression models were used to determine the risk factors associated with postdilation IOP changes. Change in IOP and SS-OCT parameters from baseline. Seventy-eight eyes from 78 patients were included, with 78, 66, and 12 patients completing the study at PDH1, PDH4, and PDH6, respectively. Mean IOP increased from 14.8 ± 2.6 mmHg at baseline to 15.5 ± 3.5 mmHg at PDH1 (P= 0.03) and decreased to 14.9 ± 3.1 mmHg at PDH4 (P= 0.09). Four patients (5.13%) and 3 patients (3.85%) had an increase in IOP ≥ 5 mmHg at PDH1 and PDH4, respectively. Two patients (2.56%) and 1 patient (1.28%) had an increase in IOP ≥ 8 mmHg at PDH1 and PDH4, respectively. None developed acute primary angle-closure during the observation period. Almost all anterior chamber parameters showed a significant increase after dilation at PDH1 and PDH4, except lens vault and iris volume, which decreased at PDH1 and PDH4 from baseline. Increase in anterior chamber depth was negatively associated with the level of IOP elevation after dilation (P < 0.01). Dilation of patients' eyes with PACS and VSC in this cohort appears to have a low risk for IOP spike. This may be associated with relaxation of the ciliary muscle leading to posterior displacement of the lens-iris diaphragm and deepening of the anterior chamber.

Changes in ocular biometric parameters after renal transplantation.

This study aimed to investigate the changes in postoperative ocular biometric parameters in end-stage renal disease patients who underwent renal transplantation. This retrospective study included a total of 33 eyes of 33 patients. The ocular biometric measurements which were evaluated were axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), corneal keratometry (K1 and K2), degree of astigmatism, lens thickness (LT), and intraocular pressure (IOP). Refractive prediction error (RE) was calculated before and after renal transplantation using the same diopter (D) for intraocular lens (IOL) power calculation and evaluated for potential cataract surgery. The study included 15 male (45%) and 18 female (55%) patients. Mean patient age was 31.55 ± 8.24 (range: 18-49 years). In the comparison of preoperative and 1-month postoperative measurements, there was a statistically significant difference in AL, LT, ACD, and CCT (p < 0.001). There was no statistically significant difference between K1, K2, and astigmatism measurements (p = 0.72; p = 0.35; p = 0.62, respectively). There was no statistically significant difference in RE (p = 0.61-Holladay 2). While renal transplantation surgery does not lead to significant changes in astigmatism, predicted refractive error, corneal keratometry, or intraocular pressure, it causes significant decrease in axial length, lens thickness, and central corneal thickness and significant increase in anterior chamber depth. However, these changes do not result in significant changes in IOL power calculation in planned cataract surgery.

Effects of pupillary dilation on ocular optical biometry outcomes in pediatric patients.

Pharmacological pupillary dilation is performed in comprehensive ophthalmological examinations and before biometric measurements. So far, there is no consensus regarding its impact on biometric measurements. This study's aim was to investigate the effects of pharmacological pupillary dilation on ocular biometric measurements in healthy children. This was a prospective, observational, non-randomized study of children (4-18 years of age) who were admitted for routine ophthalmological examination. Biometric measurements were performed, using a non-contact optical biometry device, both before and after pharmacological pupillary dilation with cyclopentolate hydrochloride. Intraocular lens power calculations were performed using Hill-RBF, Barrett, Olsen, Sanders-Retzlaff-Kraff/Theoretical, Holladay, and Hoffer Q formulas. Descriptive statistical analyses were also performed. The Wilcoxon signed-rank test was used to compare measurements before and after pharmacological pupillary dilation. Relationships between variables were analyzed using the Spearman-Brown rank correlation coefficient. The study included 116 eyes of 58 children (mean age, 8.4 ± 0.32 years; 34 girls). Significant changes were observed after pupillary dilation, compared with before pupillary dilation, in terms of anterior chamber depth, aqueous depth, and central corneal and lens thicknesses. No significant change was observed in axial length. Intraocular lens power calculations revealed no significant changes after pupillary dilation in most formulas except for the Olsen formula. The intraocular lens power was significantly inversely correlated with axial length and anterior chamber depth. Pharmacological pupillary dilation in children appeared to have no impact on axial length and intraocular lens power, but caused a significant increase in anterior chamber depth. The difference in anterior chamber depth measurements before and after pupillary dilation could be related to the optical biometry device model used. These outcomes should be considered in intraocular lens power calculations performed using anterior chamber depth parameters.

The effect of cycloplegia on biometric measurements using swept‐source optical coherence tomography‐based biometry

BackgroundTo evaluate the effect of pupil dilation obtained with cyclopentolate on biometric measurements using swept‐source optical coherence tomography biometry.MethodsThis study involved 63 eyes of 63 healthy volunteers. After ophthalmic examination, biometry measurements of the participants were obtained with IOL Master 700 (Carl Zeiss Meditec AG, Jena, Germany). After pre‐dilation measurements were taken, subjects were given one drop of cyclopentolate hydrochloride ophthalmic solution three times at 10‐minute intervals. When cycloplegia had been achieved, a dilated fundus examination was conducted and post‐dilation measurements were taken with IOL Master 700. The biometric parameters were recorded and SPSS Software 22.0 was used for statistical analysis.ResultsThere was a significant increase in anterior chamber depth, anterior aqueous depth and central corneal thickness values after pupil dilation (p < 0.05). A significant decrease was observed in lens thickness values after cycloplegia (p < 0.05). There were no statistically significant differences between pre‐dilation and post‐dilation axial length, keratometry (K1, K2) and white‐to‐white values (p > 0.05).ConclusionThis study demonstrated there is no significant difference in axial length and keratometry measurements using swept‐source optical coherence tomography biometry before and after cycloplegia.

Change in central corneal thickness, corneal endothelial cell density, anterior chamber depth and axial length after repair of rhegmatogenous retinal detachment.

Objective:To compare the effects of Pars Plana Vitrectomy (PPV) and Scleral Buckling (SB) with reference to Central Corneal Thickness (CCT), Corneal Endothelial-Cell Density (CED), Anterior Chamber Depth (ACD) and Axial Length (AL) in repair of Rhegmatogenous Retinal Detachment (RRD).Methods:This comparative cross sectional analytical study was conducted at Armed Forces Institute of Ophthalmology (AFIO), Rawalpindi from July 2013 to July 2015. A total of 69 eyes of 69 patients which underwent repair of RRD by either PPV or SB were analyzed to compare mean change in CCT, CED, ACD and AL between two groups.Results:Mean age of patients was 56.23±5.22 years. Mean pre-operative CCT, CED, ACD and AL in PPV group was 533.06±13.28µm, 2231.67±164.57Cells/mm2, 3.37±0.18mm and 23.66±0.76mm respectively. Mean post-operative CCT, CED, ACD and AL in PPV group was 534.81±11.83µm, 2037.19±167.83 Cells/mm2, 3.24±0.13mm and 23.88±0.80mm respectively. Change in CED, ACD and AL from pre-operative value after PPV was statistically significant (p<0.001). Mean pre-operative CCT, CED, ACD and AL in SB group was 530.73±12.59 µm, 2161.79±161.96 Cells/mm2, 3.343±0.14mm and 23.67±0.82mm respectively. Mean post-operative CCT, CED, ACD and AL in SB group was 532.76±7.74 µm, 2158.27±156.58 Cells/mm2, 3.24±0.10mmand 25.71±0.86mm respectively. Change in ACD and AL from pre-operative value after SB was statistically significant (p<0.001). Mean change of CED, ACD and AL between two groups was also statistically significant (p<0.001).Conclusion:Rhegmatogenous retinal detachment repair causes ocular changes, with significantly more decrease in corneal endothelial cell density after pars plana vitrectomy, and more increase in anterior chamber depth and axial length after scleral buckling.

Relationship between anterior segment and optic nerve head parameters in healthy subjects.

To determine the relationship between anterior segment and optic nerve head (ONH) parameters. Two hundred healthy subjects were enrolled in this study. The par-ticipants underwent measurement of anterior segment parameters with a Pentacam Scheimpflug system and imaging of the optic disc with confocal scanning laser ophthalmoscopy. Pearson's correlation coefficient was calculated to assess the associations between ONH and anterior segment parameters. Multivariate regression analyses controlling for age and disc area as confounding factors were also conducted. There were significant negative relationships between optic disc area and corneal thickness (p=0.03, r=-0.217) and volume (p=0.017, r=-0.239). Corneal refractive power was significantly correlated with cup area, rim area, rim volume, and cup/disc ratio (p<0.05 for all). An increase of 1 diopter in anterior corneal refractive power corresponded to a decrease of 0.022 in cup/disc ratio. Rim volume was negatively correlated with anterior chamber depth and anterior chamber volume (p<0.05 for both). A 1-mm3 increase in anterior chamber depth corresponded to a 0.154-mm3 decrease in rim volume. Mean and maximum cup depth measurements were not associated with any of the anterior segment parameters. In nonglaucomatous eyes, the dimensions and shape of the ONH may be related to anterior segment morphology. Therefore, it may be helpful to take anterior segment parameters into consideration in evaluating the OHN.

Analysis of myopia and axial length changes and relevant factors of children aged 7 to 14 years in Wenzhou

To investigate the incidence and features of myopia in children aged 7 to 14 years. Cross-sectional study. A total of 2 226 children (2 226 eyes) aged 7 to 14 years were selected from school during June 2012 and January 2015. Refraction was measured by fast cycloplegic retinoscopy. SPSS16.0 was used to analyze the data. Ocular refractive parameters, including axial length (AL), corneal power, anterior chamber depth, and white to white, were measured by IOLMaster (version 5.0, Carl Zeiss, Germany). Only the right eyes were included in the analysis. (1) The incidence of myopia in children increased with age. The incidence of myopia in female children was higher than male children with the same age. The overall incidence of myopia in female children was higher than male children (χ(2)=4.284, P=0.036). The average AL was (23.53±1.12) mm in male children and (23.44±1.08) mm in female children, and there was no statistically significant difference (t=1.502, P=0.134). (2) The change of refractive parameters was as follows. The AL elongated with age ,the average AL located in (22.84±0.87) to (24.49±1.19) mm(F=10.076, P<0.001) . The anterior chamber became deepened with age,the average ACD located in (3.28±0.16) to (3.67±0.24) mm (F=8.059, P<0.001). The white to white reduced slightly with age, the average WTW located in (12.30 ± 0.35) to (12.16 ± 0.54) mm,although there was no significant difference (F=0.469, P=0.857). There was no difference in the corneal power with age ,the average corneal power located in (43.05±1.31) to (43.74±1.20) D(F=0.440, P=0.877). The values of AL, anterior chamber depth in the myopia group were greater than the emmetropia group with the same age (P<0.05). (3) Correlation factor analysis of AL was as follows. Mixed effects model displayed that the age, height, and body weight were related to eye axis. The regression equation of AL was: AL=19.120 4+0.124 2×A+0.019 6×H+ 0.015 3×W. The AL was positively correlated with the body height (r=0.527, P< 0.01) and weight (r=0.47, P< 0.01). Among children aged 7 to 14 years, the incidence of myopia, AL, and anterior chamber depth increase with age. During the period of rapid physical development, the refraction and AL should be monitored. The prevalence of myopia is relatively high in girls, which may be associated with outdoor activity. (Chin J Ophthalmol, 2016, 52: 514-519).

ANATOMO-TOPOGRAPHIC AND HYDRODYNAMIC PARAMETERS OF THE EYE AFTER CATARACT PHACOEMULSIFICATION

Актуальность. Удаление нативного хрусталикавызывает изменение взаимного расположения структур переднего отдела глазного яблока, что влечет за собой колебания внутриглазного давления. Контроль внутриглазного давления важен для предотвращения осложнений в раннем послеоперационном периоде.

Effect of Goniosynechialysis During Phacoemulsification on IOP in Patients With Medically Well-controlled Chronic Angle-Closure Glaucoma.

To evaluate and compare the efficacy and safety of combined phacoemulsification and goniosynechialysis (PEGS) to phacoemulsification alone (PE) in patients with medically well-controlled chronic angle-closure glaucoma (CACG) with cataracts. Thirty eyes diagnosed with CACG and requiring cataract surgery from January 2008 to October 2010 were prospectively randomized, 15 each to PE and PEGS. Changes in peripheral anterior synechiae (PAS), intraocular pressure (IOP), anterior chamber depth, and number of antiglaucoma drugs from baseline to 2 months after the operation were analyzed, as were the type and number of complications. The PE group showed decreases in PAS (118.67±95.38 degrees) and IOP (2.33±2.38 mm Hg) and a significant reduction in the number of antiglaucoma drugs (0.53±0.83, P<0.05) from before to 2 months after surgery. The PEGS group showed similar decreases in PAS (114.00±90.95 degrees), and IOP (4.53±4.16 mm Hg) and number of antiglaucoma drugs (1.20±1.32) (P<0.05). However, the amount of decline in both the groups did not show any significantly difference in PAS, reduction of IOP, or number of antiglaucoma drugs (P>0.05), The increase in anterior chamber depth from baseline to 2 months after surgery was significantly greater in the PEGS group (P=0.003). The IOP-lowering effects of PEGS do not differ significantly from those of PE in medically well-controlled CACG patients with cataract. These results suggest that additional goniosynechialysis during phacoemulsification is not necessary in such patients.

Comparison of surgical outcomes after phacotrabeculectomy in primary angle-closure glaucoma versus primary open-angle glaucoma

PurposeTo compare postoperative outcomes and assess factors associated with intraocular pressure (IOP) reduction after phacotrabeculectomy in patients with primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). MethodsThis is a retrospective study of patients who underwent phacotrabeculectomy between 2010 and 2013. Factors including age, gender, visual field (VF), the number of glaucoma medications used, biometric changes, IOP, and surgical success rates were compared between groups. ResultsThere were 27 PACG and 34 POAG patients. The PACG group had a greater mean IOP reduction after phacotrabeculectomy compared to the POAG group (5.5 ± 7.9 mmHg versus 2.0 ± 4.2 mmHg; p = 0.03). However, the final mean IOP was similar between the two groups (PACG: 12.2 ± 4.8 mmHg, POAG: 12.3 ± 3.1 mmHg; p = 0.92). Phacotrabeculectomy resulted in a mean decrease in axial length (AL) of 0.16 ± 0.15 mm in PACG and 0.16 ± 0.11 mm in POAG (p = 0.96), and an increase in anterior chamber depth (ACD) of 1.41 ± 0.91 mm in PACG, and 0.87 ± 0.86 mm in POAG (p = 0.04). At 2 years follow-up, the cumulative success rate of phacotrabeculectomy was 74% in PACG and 62% in POAG. Multivariate analysis found that early glaucoma stage, greater postoperative increase in ACD, and high preoperative IOP were factors associated with greater IOP reduction. ConclusionPostoperative success rates and mean IOP on the final visit after phacotrabeculectomy were similar between the PACG and POAG groups. Factors associated with IOP reduction were greater postoperative increase in ACD, and high preoperative IOP.

Development of a Rat Schematic Eye From In Vivo Biometry and the Correction of Lateral Magnification in SD-OCT Imaging

Optical magnification in optical coherence tomography (OCT) depends on ocular biometric parameters (e.g., axial length). Biometric differences between eyes will influence scan location. A schematic model eye was developed to compensate for lateral magnification in OCT images of the healthy rat. Spectral-domain optical coherence tomography images were acquired in 19 eyes of 19 brown Norway rats. Images were scaled using the OCT instrument's built-in scaling function and by calculating the micron per degree from schematic model eyes developed from in vivo biometry (immersion A-scan and videokeratometry). Mean total retinal thickness was measured 500 μm away from the optic nerve head and optic nerve head diameter was measured. Corneal curvature, lens thickness, and axial length were modified to calculate their effects on OCT scan location and total retinal thickness. Mean total retinal thickness increased by 21 μm and the SD doubles when images were scaled with the Built-in scaling (222 ± 13 μm) compared with scaling with individual biometric parameters (201 ± 6 μm). Optic nerve head diameter was three times larger when images were scaled with the Built-in scaling (925 ± 97 μm) than the individual biometric parameters (300 ± 27 μm). Assuming no other change in biometric parameters, total retinal thickness would decrease by 37 μm for every millimeter increase in anterior chamber depth due to changes in ocular lateral magnification and associated change in scan location. Scaling SD-OCT images with schematic model eyes derived from individual biometric data is important. This approach produces estimates of retinal thickness and optic nerve head size that are in good agreement with previously reported measurements.

Ocular Changes after Simulated Ejection Following Orthokeratology

Purposes: To determine the stability of subjects' visual acuity, refraction, corneal topography, pachymetry, anterior chamber depth, and intraocular pressure following overnight orthokeratology when subjected to vertical acceleration at six times the force of gravity (+6 Gz) in a simulated ejection system on the ground. Methods: The subjects were 10 healthy male flight surgeons, aged 25-26 years (mean 25.3), who had undergone overnight orthokeratology for two weeks before controlled rapid-sequence ejection at +6 Gz. Their visual acuity, refraction, and corneal parameters, including corneal curvature, corneal thickness, anterior chamber depth, and intraocular pressure, were recorded before, immediately after, and 20 min after the +6 Gz ejection. We compared the study group findings with those of a control group of 20 subjects who had not undergone orthokeratology but were exposed to the same ejection procedure. Results: The measurements of visual acuity, refraction, and Orbscan topographic parameters, including the anterior and posterior corneal curvatures, central corneal thickness, and intraocular pressure, made before, immediately after, and 20 min after ejection did not differ significantly between the pre- and post ejection values on paired t tests. The only significant difference in the orthokeratology group was in the anterior chamber depth, which was 2.978 mm before ejection and 3.01mm 20 min after ejection (p ＜ 0.05). Conclusion: The visual acuity, refraction, and corneal topographic changes in patients after orthokeratology are stable under rapid vertical ejection at six times the force of gravity. An increase in anterior chamber depth was the only significant change after ejection in the orthokeratology group.