Measurements of anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter using two Scheimpflug imaging devices

Purpose. We aimed to investigate whether anterior chamber angle, depth, and volume change after myopic laser-assisted in situ keratomileusis (LASIK) in young patients. Methods. This retrospective study included 29 eyes of 29 patients (15 females and 14 males) between the ages of 18 and 39 years who underwent LASIK for the treatment of myopia. In addition to complete ophthalmic examination, anterior chamber angle (ACA), central anterior chamber depth (ACD), and anterior chamber volume (ACV) were measured by using a Sirius rotating Scheimpflug camera combined with Placido disc corneal topography (CSO, Florence, Italy). Preoperative and postoperative values were compared using paired t-tests. Linear regression was used to evaluate the relationship between changes in refraction and changes in ACA, ACD, and ACV as well as between attempted maximum ablation depth and changes in ACA, ACD, and ACV. Results. The mean age of the study population was 25.5 ± 6.2 years. The mean preoperative and postoperative spherical equivalent values were −3.30 ± 1.92 D and −0.18 ± 0.29 D, respectively. ACV and ACA were not significantly changed after surgery; however, central ACD was significantly decreased (preoperatively = 3.366 ± 0.316 mm vs postoperatively = 3.3 ± 0.298 mm) with a mean difference of 0.066 ± 1.121 mm. There were no significant relationships between changes in refraction and anterior segment dimensions or between attempted maximum ablation depth and anterior segment dimensions. Conclusion. Measurements with Sirius showed that ACA and ACV did not change; however, central ACD significantly decreased after myopic LASIK in young patients, indicating that the preoperative central ACD value should not be used interchangeably with the postoperative central ACD value.

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The changes of anatomic and topographic characteristics of eye anterior segment after uncomplicated cataract phacoemulsification

Kazan medical journal ◽

10.17816/kmj1805 ◽

2013 ◽

Vol 94 (6) ◽

pp. 853-858

Author(s):

A A Ryabtseva ◽

M P Yugaj ◽

N S Nikitina

Keyword(s):

Intraocular Pressure ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Ultrasound Biomicroscopy ◽

Anterior Chamber Angle ◽

Ciliary Processes ◽

Lens Implantation ◽

Topographic Characteristics ◽

Chamber Angle

Aim. To study the changes of anatomic and topographic characteristics of the eye anterior segment after uncomplicated cataract phacoemulsification using corneal incision with intraocular soft lens implantation. Methods. The data of ultrasound biomicroscopy and noncontact tonometry of 58 eyes (56 patients, 32 females, 24 males aged 54 to 78 years) before and after cataract phacoemulsification were analyzed. Paitents with survived ocular trauma, refractive keratoplasty, glaucoma, uveitis, and surgical complications (incomplete capsulorrhexis, posterior capsule rupture, ciliary zonule disinsertion, corneal burn). Apart from the common examinations (visual acuity testing, tonometry, tonography, eye A- and B-ultrasonography, biomicroscopy), all patients underwent eye ultrasound biomicroscopy. Results. Anterior chamber depth increased from 2.73±0.10 to 4.17±0.06 mm (p ≤0.001). Trabecula-iris distance measured at 500 μm from the scleral spur, increased from 0.38±0.02 to 0.47±0.02 mm (p ≤0.001). Anterior chamber angle increased from 28.69±1.87 to 42.73±1.56 degrees (p ≤0.001), the angle between the iris and the sclera increased from 32.78±1.39 to 41.36±0.84 degrees (p ≤0.001), the angle between the sclera and ciliary processes increased from 39.48±1.29 to 45.30±1.16 degrees (p ≤0.001). Intraocular pressure according to the non-contact tonometry data decreased from 18.16±1.29 to 13.55±0.95 mm Hg (p ≤0.001). Conclusion. Anterior chamber depth, trabecula-iris distance, anterior chamber angle, the angle between sclera and iris and the angle between sclera and ciliary processes increased significantly after phacoemulsification with intraocular lens implantation. Intraocular pressure decreased significantly according to the non-contact tonometry data.

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Anterior chamber angle imaging with swept-source optical coherence tomography: comparison between CASIAII and ANTERION

Scientific Reports ◽

10.1038/s41598-020-74813-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Poemen Pui-man Chan ◽

Gilda Lai ◽

Vivian Chiu ◽

Anita Chong ◽

Marco Yu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Angle Closure ◽

Optical Coherence ◽

Anterior Chamber Angle ◽

Swept Source ◽

Scan Pattern ◽

Chamber Angle

Abstract This study compared the test–retest variabilities and measurement agreement of anterior chamber angle (ACA) dimensions measured by two anterior segment swept-source optical coherence tomography (SS-OCT)—the ANTERION (Heidelberg Engineering, Heidelberg, Germany) and CASIAII (Tomey, Nagoya, Japan). Thirty-eight subjects, 18 patients with primary angle closure and 20 healthy participants with open angles, were included. The mean age was 54.7 ± 15.8 years (range: 26–75 years). One eye of each subject was randomly selected for anterior segment imaging by ANTERION and CASIAII, using the same scan pattern (6 evenly spaced radial scans across the anterior segment for three times) in the same visit. The between- and within-instrument agreement and repeatability coefficients of angle open distance (AOD500), trabecular-iris space area (TISA500), lens vault (LV), scleral spur-scleral spur distance (SSD), anterior chamber depth (ACD), and pupil diameter (PD) were measured. The anterior and posterior boundaries of the cornea, iris, and lens were automatically segmented by the SS-OCT instruments; the scleral spur was manually located by a single masked observer. There were significant differences between ANTERION and CASIAII measurements; the SSD, PD, and ACD were smaller whereas AOD500 and TISA500 were greater in ANTERION compared with CASIAII (P < 0.001). Anterior segment measurements obtained from the two SS-OCT instruments showed strong associations (R2 ranged between 0.866 and 0.998) although the between-instrument agreement was poor; the spans of 95% limits of between-instrument agreement were ≥ 1.5-folds than the within-instrument agreement for either instrument. Whereas both SS-OCT instruments showed low test–retest measurement variabilities, the repeatability coefficients of AOD500, TISA500, ACD, and PD were slightly smaller for CASIAII than ANTERION (P ≤ 0.012).

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Assessment of anterior chamber angle changes after phacoemulsification with swept-source OCT

International Journal of Ophthalmology ◽

10.18240/ijo.2021.10.08 ◽

2021 ◽

Vol 14 (10) ◽

pp. 1527-1532

Author(s):

Qian Zheng ◽

◽

Zhang-Liang Li ◽

Ping-Jun Chang ◽

Yun-E Zhao ◽

...

Keyword(s):

Intraocular Pressure ◽

Cataract Surgery ◽

Anterior Chamber ◽

Anterior Chamber Depth ◽

Anterior Chamber Angle ◽

Swept Source ◽

Narrow Angle ◽

Significant Difference ◽

Shallow Anterior Chamber ◽

Chamber Angle

AIM: To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens (IOL) implantation, based on anterior segment swept-source optical coherence tomography (AS-SS-OCT) measurements. METHODS: This was a prospective case control study; sixty eyes of sixty case were scheduled for cataract surgery with normal intraocular pressure (IOP). Based on anterior chamber depth (ACD) and gonioscopy findings, the eyes were divided into two groups: group of shallow anterior chamber and narrow angle (SAC group, 30 eyes); and group of normal anterior chamber group with wide angle (NAC group, 30 eyes). Measurements of ACD, anterior chamber volume (ACV), iris volume (IV), lens vault (LV), angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), and trabecular iris angle (TIA) were conducted in each group before and 3mo after surgery. RESULTS: There was no significant difference in age, axial length (AL), corneal curvature, corneal diameter, intraocular pressure, and IV between two groups before surgery, except for the LV (P=0.000). ACD and ACV were prominently larger in the NAC group than the SAC group 3mo after operation (3.69±0.38 vs 3.85±0.39 mm, P=0.025; 161.37±19.47 vs 178.26±20.30 mm3, P=0.002). AOD750, ARA750 in nasal and inferior quadrants, TISA750 in all quadrants except temporal, and TIA750 in all quadrants in SAC group were significantly smaller than those in NAC group after operation (all P<0.05). CONCLUSION: Cataract surgery can deepen anterior chamber and increase the width of anterior chamber angle in Chinese subjects, but the angle related parameters including AOD750, ARA750, TISA750, TIA, TISA750, and ACV in patients with shallow anterior chamber and narrow angle do not reach the normal level.

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Diagnostic Value of Modern Methods of Ocular Anterior Segment Visualization in Intumescent Cataract

Ophthalmology in Russia ◽

10.18008/1816-5095-2019-3-350-354 ◽

2019 ◽

Vol 16 (3) ◽

pp. 350-354

Author(s):

O. L. Fabrikantov ◽

S. I. Nikolashin ◽

E. S. Pirogova

Keyword(s):

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Ultrasound Biomicroscopy ◽

Diagnostic Value ◽

Ligament Length ◽

Anterior Chamber Angle ◽

Lens Thickness ◽

Scheimpflug Camera ◽

Chamber Angle

Purpose: tо evaluate the diagnostic capabilities of optical coherence tomography (OCT), Scheimpflug camera and ultrasound biomicroscopy (UBM) in examining topography of the ocular anterior segment and lens in mature intumescent cataract. Patients and methods. 23 eyes with mature intumescent cataract were examined using OCT (RTVue-100, Optovue, USA), Scheimpflug camera (Pentacam HR, Oculus, Germany) and UBM (UD 8000, Tomey, Japan). We examined the anterior chamber depth, profile and magnitude of the anterior chamber angle, distance “trabecula-iris at 500 microns”, thickness of the liquid lenticular mass layer, lens thickness, Zinn ligament length within four segments, equatorial angle. Results. We managed to measure the anterior chamber depth using UBM and Scheimpflug camera. UBM measurement was 1.96 ± 0.14 mm, Scheimpflug camera — 1.91 ± 0.11 mm. We revealed narrowing of the anterior chamber angle up to 11.54 ± 2.19° in UMB examination, to 11.49 ± 2.17° in OCT measuring and to 11.63 ± 2.21° in examining by Scheimpflug camera. Distance “trabecula-iris 500” was 0.212 ± 0.037 mm in UMB examination, 0.218 ± 0.042 mm — by means of OCT, Scheimpflug camera measurement was unsuccessful. The rest parameters were examined only by UBM. The lens thickness was 5.26 ± 0.13 mm. The anterior layer of liquid lenticular mass was 0.85 ± 0.06 mm. Zinn ligament length in the outer segment was 0.708 ± 0.072 mm, in the internal segment — 0.731 ± 0.089 mm, in the superior segment — 0.704 ± 0.084 mm, in the inferior segment — 0.876 ± 0.089 mm. The equatorial angle in two opposite segments was 32.52 ± 0.92°. Conclusion. Ultrasound biomicroscopy has the biggest value in examining topography of the ocular anterior segment and lens in mature intumescent cataract, since only this method allows achieving the whole complex of data necessary to evaluate the swelling lens parameters. This can serve as a basis for developing the appropriate tactics of surgical intervention.

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Distribution of Anterior Chamber Angle Width and Correlation With Age, Refraction, and Anterior Chamber Depth—The Gutenberg Health Study

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.16-19600 ◽

2016 ◽

Vol 57 (8) ◽

pp. 3740 ◽

Cited By ~ 5

Author(s):

Alexander K. Schuster ◽

Norbert Pfeiffer ◽

Stefan Nickels ◽

Andreas Schulz ◽

René Höhn ◽

...

Keyword(s):

Anterior Chamber ◽

Anterior Chamber Depth ◽

Health Study ◽

Anterior Chamber Angle ◽

Gutenberg Health Study ◽

Angle Width ◽

Chamber Angle

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Ocular biometric changes after Ahmed glaucoma valve implantation

European Journal of Ophthalmology ◽

10.1177/1120672119889528 ◽

2019 ◽

pp. 112067211988952

Author(s):

Arezoo Miraftabi ◽

Mahboubeh Lotfi ◽

Naveed Nilforushan ◽

Parya Abdolalizadeh ◽

Samira Jafari

Keyword(s):

Anterior Chamber ◽

Axial Length ◽

Anterior Chamber Depth ◽

Ahmed Glaucoma Valve ◽

Anterior Chamber Angle ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

Valve Implantation ◽

Ahmed Glaucoma Valve Implantation ◽

Chamber Angle

Purpose: To investigate the ocular biometric changes after uneventful Ahmed glaucoma valve implantation. Methods: Patients with refractory glaucoma who were candidate for Ahmed valve surgery were prospectively included in this study. Patients with a history of any kinds of corneal surgery were excluded. Refractive status, intraocular pressure, axial length, anterior chamber parameters including anterior and posterior mean keratometry, central corneal thicknesses, and anterior chamber depth, anterior chamber volume, and anterior chamber angle were evaluated at baseline and 1 and 3 months after surgery. Results: A total of 20 eyes from 20 patients were included. Mean intraocular pressure at baseline was 33.4 ± 12.3 mm Hg that significantly decreased to 14.6 ± 6.2 mm Hg at 1 month and 13.5 ± 4.3 mm Hg at 3 months after Ahmed glaucoma valve implantation ( p < 0.001). Mean number of medications was 3.6 ± 1.3 at baseline which significantly decreased to 1.0 ± 1.3 at 3 months after Ahmed glaucoma valve implantation ( p < 0.001). Axial length decreased significantly from 23.69 ± 1.95 to 23.47 ± 1.91 mm ( p < 0.001) at month 3. There were no significant changes in other parameters such as mean spherical equivalent, anterior chamber volume, anterior chamber angle, anterior chamber depth, and keratometry at the end of month 3 after surgery ( p > 0.05 in all). Conclusion: Ahmed glaucoma valve implantation had a significant effect on axial length at 3 months after surgery but its effect on keratometry and other anterior chamber parameters was not significant.

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Gonioscopy

Glaucoma ◽

10.1093/oso/9780199757084.003.0007 ◽

2012 ◽

Author(s):

Morales Jose

Keyword(s):

Anterior Chamber ◽

False Negative ◽

Anterior Chamber Depth ◽

Acute Angle ◽

Angle Closure Glaucoma ◽

Angle Closure ◽

Anterior Chamber Angle ◽

Negative Results ◽

Laser Trabeculoplasty ◽

Chamber Angle

Gonioscopy allows visualization of the anterior chamber angle using special lenses. The anterior chamber angle cannot be visualized by direct observation because of its position in the angle recess and the phenomenon of total internal reflection of the light caused by the cornea. Goniolenses with appropriate optical properties and mirrors or prisms allow adequate visualization of its structures through a “periscope effect” and provide a more favourable reflection angle. Clinical circumstances where gonioscopy is essential or helpful in the diagnosis and management of glaucoma are as follows: • To diagnose primary angle closure and to assess the results of medical, laser, or surgical treatment on angle configuration • The Van Herick method of estimating the peripheral anterior chamber depth with the slit lamp gives a useful but rough estimate and does not replace gonioscopy. It can give false-negative results in patients with plateau iris configuration and false-positive results in patients with moderate anterior chamber depth but an open angle. • To assess the risk of angle closure in patients with shallow anterior chambers before undergoing pupillary dilation • To diagnose and follow treatment of acute angle-closure glaucoma attacks To establish the diagnosis of secondary angle-closure glaucoma • To determine precise anatomic landmarks for accurate laser application during trabeculoplasty • For the evaluation and follow-up of congenital or acquired abnormalities of the anterior chamber angle • To detect and evaluate mass lesions that affect the anterior chamber angle • To evaluate the anatomic angle changes and patency of the ostium after trabeculectomy • To visualize the angle during “angle surgery” • Such as goniotomy, trabectome surgery,or trabecular micro-bypass stent •During laser trabeculoplasty and after laser iridoplasty Three goniolens prototypes have been most used in the past and represent the precursors of newer lenses Their main features are displayed on Table 2.1. Explain the procedure to the patient and its purpose. Reassure him or her that with the use of topical anesthetic the test will not be painful, and request cooperation in terms of avoiding lid squeezing and excessive eye movement during the exam.

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Evaluation of the Anterior Chamber Angle in Angle-Closure Suspect Patients by Anterior Segment Optical Coherence Tomography (AS-OCT) and Pentacam

10.21203/rs.3.rs-684174/v1 ◽

2021 ◽

Author(s):

Mohamed Salah El-Din Mahmoud ◽

Nosiba Essam ◽

Layla Mohamed Hammouda ◽

Ahmed Shawkat Mohamed

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Angle Closure ◽

P Value ◽

Optical Coherence ◽

Anterior Chamber Angle ◽

Cross Sectional ◽

Chamber Angle

Abstract Purpose: The study aims is to detect primary angle-closure glaucoma (PACG) suspects using both anterior segment optical coherence tomography (AS-OCT) and Scheimpflug imaging. Methods: A prospective cross-sectional observational study on forty PACG suspect patients with a range of ages from 20 to 70 years. Angle imaging by AS-OCT (Optovue Inc., Fairmont, CA) with study parameters in the superior, inferior, nasal, and temporal quadrants were anterior chamber angle (ACA), angle opening distance at 750 µm (AOD750), and trabecular-iris space area at 750 μm (TISA). Also, angle imaging using Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany) with study parameters were the anterior chamber angle (ACA), anterior chamber depth (ACD) and, anterior chamber volume (ACV). The angle evaluation was done before and after the mydriatic test.Results: As regarding AS-OCT, after the mydriatic test, we noticed a decrease in all parameters measured, some decreased significantly while others did not. A significant decrease was noticed in ACA (TIA750) in all quadrants (P value<0.001in nasal, 0.001in superior &temporal, 0.003 in inferior) and in TISA750 in the nasal quadrant only (P-value 0.004). AOD750 and TISA750 in the remaining quadrants also decreased but not significantly as ACA. As regarding Pentacam, all parameters decreased after the mydriatic test. ACA (P-value <0.001) and ACD (P-value 0.004) showed significant statistical decrease but ACV showed statistically non-significant decrease (P-value 0.558).Conclusions: AS-OCT and Pentacam are reliable investigations for the detection of PACG suspects which needs more close follow-up for a possible increase in IOP.

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