Anterior Chamber Configuration Research Articles

Analysis of anterior segment in primary angle closure suspect with deep learning models

ObjectiveTo analyze primary angle closure suspect (PACS) patients’ anatomical characteristics of anterior chamber configuration, and to establish artificial intelligence (AI)-aided diagnostic system for PACS screening.MethodsA total of 1668 scans of 839 patients were included in this cross-sectional study. The subjects were divided into two groups: PACS group and normal group. With anterior segment optical coherence tomography scans, the anatomical diversity between two groups was compared, and anterior segment structure features of PACS were extracted. Then, AI-aided diagnostic system was constructed, which based different algorithms such as classification and regression tree (CART), random forest (RF), logistic regression (LR), VGG-16 and Alexnet. Then the diagnostic efficiencies of different algorithms were evaluated, and compared with junior physicians and experienced ophthalmologists.ResultsRF [sensitivity (Se) = 0.84; specificity (Sp) = 0.92; positive predict value (PPV) = 0.82; negative predict value (NPV) = 0.95; area under the curve (AUC) = 0.90] and CART (Se = 0.76, Sp = 0.93, PPV = 0.85, NPV = 0.92, AUC = 0.90) showed better performance than LR (Se = 0.68, Sp = 0.91, PPV = 0.79, NPV = 0.90, AUC = 0.86). In convolutional neural networks (CNN), Alexnet (Se = 0.83, Sp = 0.95, PPV = 0.92, NPV = 0.87, AUC = 0.85) was better than VGG-16 (Se = 0.84, Sp = 0.90, PPV = 0.85, NPV = 0.90, AUC = 0.79). The performance of 2 CNN algorithms was better than 5 junior physicians, and the mean value of diagnostic indicators of 2 CNN algorithm was similar to experienced ophthalmologists.ConclusionPACS patients have distinct anatomical characteristics compared with health controls. AI models for PACS screening are reliable and powerful, equivalent to experienced ophthalmologists.

Malignant glaucoma: disease course and treatment

Diagnosis of malignant glaucoma presents a challenge due to subtle symptoms in early stages of the disease, making increased intraocular pressure a pivotal indicator, often accompanied by inflammation and corneal edema. Diagnostic modalities, including ultrasound biomicroscopy and anterior segment optical coherence tomography, play crucial roles in visualizing anatomical changes in the ciliary body and anterior chamber. The classic slit lamp examination, complemented by tonometry, remains a fundamental diagnostic tool. A stepwise therapeutic approach is essential, beginning with pharmacological interventions aimed at intraocular pressure reduction and subsequent restoration of the anterior chamber configuration. The first stage of treatment is pharmacotherapy. Laser therapies, such as iridotomy and Nd:YAG laser treatment, address angle closure. In resistant cases, a surgical approach, such as irydo-zonulo-hialoidotomy may be considered.

Efficacy of the intracamerally administered mydriatics for cataract surgery in patients with primary open-angle glaucoma.

To compare Mydrane®, mydriatic eye drops, and Mydriasert® in terms of pupil site stability, surgical time, visual field, and anterior chamber configuration modifications among patients with primary open-angle glaucoma (POAG) during cataract extraction surgery. Retrospective analysis of sixty patients with POAG and cataract who underwent elective cataract extraction. All patients underwent routine ophthalmic examinations, including automatic visual field examination, anterior chamber configuration, specular microscopy, and arterial blood pressure measurement prior to surgery, and 24 h and 30 days postoperatively. All cataract surgeries were video-recorded and all measurements were performed using a media player. Patients divided into groups 1, 2, and 3 (n = 20 in each group) received topical mydriatic eye drops, Mydriasert®, and an intracameral injection of Mydrane®, respectively, immediately after the first incision. The mean change in pupil size from just before capsulorhexis to the end of surgery was 0.43 ± 0.09, 0.42 ± 0.08, and 0.36 ± 0.02 mm in groups 1, 2, and 3, respectively. The mean surgery duration was similar among all the groups. The baseline main cell density slightly decreased at 24 h and remained stable for 30 days postoperatively. The mean deviation and pattern standard deviation remained stable at 1 month after surgery. At 24 h after surgery, the nasal irido-corneal angle, temporal-iridocorneal angle, and anterior chamber depth increased compared with the baseline, remaining stable for 30 days after surgery. Mydrane® produced adequate and stable mydriasis as effectively as produced by Mydriasert® and topical eye drops.

Lowering of intraocular pressure after phacoemulsification in primary open-angle and angle-closure glaucoma: Correlation with lens thickness.

Purpose:To assess anterior chamber configuration changes during phacoemulsification in primary angle-closure suspect (PACS/PAC) and primary open-angle glaucoma (POAG).Methods:Prospective observational comparative study of anterior segment optical coherence tomography (AS-OCT) findings before and after phacoemulsification on three groups of patients (PACS/PAC, POAG, and controls). Data were collected over a period of 9 months. Main outcome measures included mean change in anterior chamber depth (ACD), angle opening distance (AOD), and trabecular iris space area (TISA).Results:153 patients (51 PACS/PAC, 51 POAG, and 51 controls) were included in the study. Change in all parameters (ACD, AOD at 500 um, and AOD at 750 um) between the groups demonstrated a greater change in PACS/PAC as compared to POAG and controls. AOD at 750 μm in the temporal quadrant, which has been considered to be having the highest correlation or best representation of the angle, increased in all groups after phacoemulsification (463.59 ± 10.99 vs. 656.27 ± 9.73 mm in PACS; 521.29 ± 16.36 vs. 674.37 ± 8.72 mm in POAG; 549.27 ± 12.40 vs. 702.82 ± 13.04 mm in controls, (P < 0.001). After phacoemulsification, intraocular pressure (IOP) decreased by 2.75 ± 1.17 mm Hg in PACS/PAC (P < 0.001), 2.14 ± 1.33 mm Hg in POAG and 1.90 ± 1.25 mm Hg in controls and it was statistically significant in the PACS group compared to control (P < 0.001).Conclusion: Phacoemulsification with intraocular lens implantation is associated with increase in the ACD and angle parameters and a corresponding decrease in IOP. Findings were more pronounced in PACS/PAC suggesting early phacoemulsification may be a treatment option in this group.

Erratum to: Reply to comment on: Distinct differences in anterior chamber configuration and peripheral aberrations in negative dysphotop.

Erratum to: Reply to comment on: Distinct differences in anterior chamber configuration and peripheral aberrations in negative dysphotop.

Anterior Chamber Configuration Changes after Phacoemulsification and Intraocular Lens Implantation Measured by Anterior Segment Optical Coherence Tomography

Background: Phacoemulsification can cause changes in the measurements of the anterior segment. Anterior segment optical coherence tomography [AS-OCT] is a disconnected probe device that can detect variations in the anterior segment parameters. The aim of the work: The current study aimed to investigate changes in anterior chamber angle [ACA] morphology and intraocular pressure [IOP] after phacoemulsification of cataract and intraocular lens implantation by comparing two groups of patients using two brands of IOL [Sensar 1 hydrophobic one-piece IOL] and [Eyecryl hydrophilic one-piece IOL] in patients with senile cataract using [AS-OCT]. Patients and Methods: Our study was a prospective randomized study including 30 eyes with impaired vision due to cataract, as the only cause of visual regression selected from the patients who attended Al-Azhar University Hospital [Damietta branch] Ophthalmic outpatient Clinic and were randomized into two groups. Group A [15 eyes] was implanted with [Sensar 1 hydrophobic IOL] and Group B [15 eyes] was implanted with [Eyecryl hydrophilic IOL]. Results: the results revealed that there was a significant increase in the AC angle in both groups, except for the AC depth in group A, but the difference between groups was statistically non-significant. Conclusion: Phacoemulsification with IOL implantation led to an increase in the ACA, a marked increase in BCVA and a reduction in IOP, if using [Sensar 1 hydrophobic one-piece IOL] or [Eyecryl hydrophilic one-piece IOL]. However, we cannot generalize the results because of the small sample size.

Posture-Related Changes of Intraocular Pressure in Patients With Acute Primary Angle Closure.

PurposeTo evaluate the posture-related change in intraocular pressure (IOP) of eyes with angle-closure disease and the associated factors.MethodsEyes were prospectively enrolled and divided into three groups: eyes with acute primary angle-closure (APAC), fellow eyes of acute primary angle-closure (FAPAC), and eyes with nonacute primary angle-closure disease (PACD). All of them had been treated with laser peripheral iridotomy. IOP was measured in the sitting, supine, and lateral decubitus positions (LDP) five minutes after posture change. Anterior chamber angle parameters and angle-closure mechanism were evaluated by anterior segment optical coherence tomography.ResultsForty-four eyes were enrolled into each group. APAC eyes showed more LDP-Sitting IOP increase than fellow eyes (5.7 ± 2.7 vs. 2.2 ± 1.4 mm Hg, P < 0.001) and nonacute PACD eyes (3.6 ± 2.0 mm Hg, P < 0.001). LDP-sitting IOP change was higher in eyes with exaggerated lens vault (having shallow anterior chamber and volcano-like iris-lens configuration) than in those without it (APAC: 6.3 ± 2.6 vs. 3.9 ± 2.1 mm Hg, P = 0.011). Linear regression revealed that LDP-sitting IOP change in the APAC group was negatively associated with angle opening distance (AOD), trabecular iris space area, scleral spur angle, and anterior chamber depth (ACD1000). With multivariable stepwise regression analysis, AOD750 remained statistically significant (beta-coefficient = −8.36, P = 0.014).ConclusionsAPAC eyes had significant posture-related IOP changes, associated with narrower angle structures and exaggerated lens vault.

Distinct differences in anterior chamber configuration and peripheral aberrations in negative dysphotopsia.

To provide insights into the anatomical characteristics associated with negative dysphotopsia using quantitative clinical data. Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands. Case-control study. Anterior chamber tomography and peripheral aberrometry were measured in 27 pseudophakic patients with negative dysphotopsia and 30 pseudophakic control subjects. Based on these measurements, the total corneal power, anterior chamber depth, pupil location and diameter, iris tilt, and peripheral ocular wavefront up to 30 degrees eccentricity were compared between both groups. In addition, ray-tracing simulations using pseudophakic eye models were performed to establish a connection between these clinical measurements and current hypotheses on the etiology of negative dysphotopsia. Twenty-seven patients with negative dysphotopsia and 25 pseudophakic controls were included in the analysis. The patients with negative dysphotopsia had a smaller (P = .03/P = <.01) and more decentered (P < .01) pupil than that of the pseudophakic controls. In addition, an increased temporal-tilted iris (P < .01) and an asymmetric peripheral aberration profile were observed in patients with negative dysphotopsia, of which the latter was also apparent in several ray-tracing models. The combination of these in vivo results and ray-tracing simulations indicated that patients with negative dysphotopsia had a temporal-rotated eye, which confirmed the hypothesized relation between negative dysphotopsia and an increased angle κ. Patients with negative dysphotopsia had a smaller pupil and an increased angle κ, which made them more susceptible to experiencing a shadow in the temporal visual field.

Anterior chamber configuration changes after phacoemulsification and IOL implantation measured by anterior segment optical coherence tomography

Objective: To measure early changes in anterior chamber morphology after phacoemulsification and IOL implantation using anterior segment optical coherence tomography. Materials and Methods: Prospective consecutive interventional study measuring the anterior chamber configuration changes in twenty(20 eyes) after 1 month of phacoemulsification and posterior chamber IOL implantation. Results: Showing significant difference regarding nasal, superior, temporal and inferior angle measured by anterior segment optical coherence tomography before and after phacoemulsification operation with p.value were (0.027_0.009_0.02_0.012) respectively. Conclusion: Quantitative values showed the anterior chamber angle (ACA),measured using AS-OCT, has increased following uneventful phacoemulsification and IOL implantation.

How do paper and electronic records compare for completeness? A three centre study.

Medical records are legal documentation of patients' care hence must be accurate and complete for both medical and legal purposes. Electronic patient record (EPR) systems aim to improve the accuracy of documentation, provide better organisation and access of data. This study compares the completeness of traditional note records and EPR in glaucoma patients. Using criteria from the April 2009 National Institute for Health and Care Excellence (NICE) guidelines completeness of data entry was compared between EPR and paper notes in three units. Moorfields Eye Hospital (City Road) uses the Openeyes EPR. Bedford Hospital (Moorfields Eye Centre) and Western Eye Hospital use the Medisoft EPR. The standard was set at 100% compliance for predetermined parameters. One hundred seventy paper notes and 270 electronic records were analysed. With the exception of central corneal thickness (p = 0.31), all other key parameters were more consistently recorded in the paper records than in the EPR. Intraocular pressure (p = 0.004), anterior chamber configuration and depth assessments using gonioscopy (p < 0.001), fundus examination (p = 0.015), past medical history (p < 0.001), medication including glaucoma medication (p < 0.001) and drug allergies (p < 0.001). Our results show that paper records are significantly more complete than EPR. This is the case for two different EPRs and three separate sites. We propose additional training to aid data-collection; improving the design of EPRs by investigating factors such as layout and use of forced choice fields.

Unusual Surprises in Glaucoma Filtering Surgeries: Lessons Learned and Review of Literature

ABSTRACTPurpose: To describe an unusual series of complications after glaucoma filtering surgeries with their clinical findings and outcome after tailored non-conventional modes of therapy. Patients and Methods: Eighteen patients who underwent re-interventions (medical or surgical) after glaucoma filtering surgeries during the period at two tertiary centers, excluding those that required conventional modes of treatment (medical control or re-trabeculectomy, simple wound closure for traumatic wound dehiscence, bleb revision or needling, laser iridotomy), were included. Relevant clinical details with intraoperative videos, intraoperative or postoperative problems, and images with course after re-intervention were retrieved from the hospital database. Clinical details which helped in clinching diagnosis and cause for problems and course after intervention with final vision and intraocular pressure were evaluated. Results: Six of 18 eyes required surgical management for an unusual course of events after an uneventful filtering surgery. Bleb morphology and close follow-up of the conjunctiva, in addition to intraocular pressure (IOP) and anterior chamber (AC) configuration, helped diagnose possible aetiology and appropriate tailored management. All patients had good IOP and visual outcome in all except one with macular scar status after retinal detachment surgery. Conclusion: Assessment of the bleb morphology in the postoperative course coupled with monitoring of the conjunctival wound are essential to conventional monitoring of IOP and anterior chamber configuration to arrive at appropriate management for rare unusual events after glaucoma surgery.

Intraocular Pressure Reduction after Phacoemulsification versus Manual Small-Incision Cataract Surgery: A Randomized Controlled Trial

To compare reduction in intraocular pressure (IOP) and change in anterior chamber angle configuration between eyes undergoing phacoemulsification versus those undergoing manual small-incision cataract surgery (MSICS). Prospective, randomized, double-masked, parallel assignment clinical trial. Five hundred eyes of 500 participants 40 to 70 years of age with normal IOP, gonioscopically open angles, and age-related cataract. Eyes underwent phacoemulsification or MSICS after a 1:1 randomization and allocation code. Best-corrected vision, IOP, comprehensive slit-lamp evaluation, and anterior segment (AS) optical coherence tomography (OCT) were performed at baseline and at 1, 3, and 6 months follow-up. Change in IOP (ΔIOP) and AS OCT parameters between baseline and 6 months after surgery. Six months, similar IOP reduction was observed in eyes undergoing phacoemulsification (ΔIOP=2.7±2.9 mmHg) and MSICS (ΔIOP= 2.6±2.6 mmHg; P= 0.70). Widening of the angle opening distance (AOD) 500 μm from the scleral spur (median ΔAOD500= 103 μm; interquartile range= 39-179 μm) was also similar in both groups (P= 0.28). Multivariate linear regression analysis showed that eyes with higher baseline IOP experienced significantly greater reduction in IOP at 6 months (ΔIOP= 0.46-mmHg reduction for every 1-mmHg increment in baseline IOP; 95% confidence interval [CI], 0.4-0.5 mmHg; P < 0.001). After adjusting for covariates, the magnitude of widening of AOD500 was not associated significantly with reduction in IOP (1.33-mmHg reduction for every 1-mm increment in AOD500; P= 0.07). Baseline AOD500 (β=-0.60-mm change/1-mm increment of baseline AOD; 95% CI,-0.67 to-0.53 mm) and anterior chamber depth (β= 0.07-mm change/1-mm increment of baseline anterior chamber depth; 95% CI, 0.04-0.1 mm) were significant predictors of AOD500 widening at 6 months. Both phacoemulsification and MSICS led to significant and similar IOP reductions 6 months after surgery, and both surgeries produced similar changes in anterior chamber and angle parameters. Higher baseline IOP was associated with greater IOP reduction; IOP reduction also can be attributed partly to changes in angle and anterior chamber configuration, although these parameters were unable to predict significantly predict IOP drop at 6 months.

Gonioscopy and ultrasound biomicroscopy in the detection of angle closure in patients with shallow anterior chamber.

To assess the agreement between gonioscopy and ultrasound biomicroscopy (UBM) in detecting angle closure in Chinese patients with shallow anterior chamber. An observational comparative study of the two different examination methods was conducted. Patients with normal intraocular pressure and temporal peripheral anterior chamber depth less than a quarter of corneal thickness based on slit lamp examination were included in this study from December 2007 to May 2009 in the outpatient clinic of First Hospital of Tsinghua University. Gonioscopy was performed with a Goldman goniolens in dark room first and followed by full beam light and indentation. If the filtering trabecular meshwork was invisible or any peripheral anterior synechia was found, that quadrant of the angle was considered closed. UBM was first undertaken in a darkened room then repeated with normal room lighting. If iridotrabecular apposition was showed, that quadrant of the angle was considered closed. The status of angle closure of each quadrant with different methods was recorded. 85 eyes of 46 patients were included in this study. The agreement between gonioscopy and UBM was poor (Κ<0.4) with Kappa analysis in both dark and light conditions in each quadrant. The accordance of agreement between gonioscopy and UBM was hardly affected by age or sex, while in dark condition, eyes with deeper anterior chamber (P=0.005) or plateau iris configuration tended to produce different results (P=0.075) in the 2 methods. Gonioscopy and UBM are both indispensable methods for detecting angle closure, neither can completely replace the other.

Comparison of slit lamp-adapted optical coherence tomography features of fellow eyes of acute primary angle closure and eyes with open angle glaucoma

The aim of this study was to assess the possibility of discriminating a narrow and occludable chamber angle by means of digital gonioscopy. In a prospective controlled clinical study 40 eyes of 40 patients were enrolled. 20 patients that had suffered acute angle closure glaucoma (ACG) on the fellow eye were compared to 20 patients with open angle glaucoma (OAG). Anterior segment imaging with SL-OCT (Heidelberg Engineering, Heidelberg, Germany) enabled the delineation, by means of automatic signal analysis, of several important parameters of the anterior chamber angle region, which were compared to those revealed from direct contact glass gonioscopy and ultrasound biometry. The anterior segment structures were automatically recognized by the SL-OCT software in 70 % of the ACG patients and in all of the OAG cases (100 %) (p = 0.025). Anterior chamber angle (ACA) was 15.55° ± 6.92° in the ACG group and 34.6° ± 8.9° in the OAG group, whereas angle opening distance (AOD) was 199.55 ± 62.29 μm in ACG and 452.67 ± 123.91 μm in OAG. A good correlation was found in the direct gonioscopic findings (r = 0.85, p < 0.001), but there were significant differences between both groups (p < 0.001). Mean real central anterior chamber depth (rACD) was evaluated to be 1.75 and 2.79 mm in ACG and OAG, respectively, showing a significant difference (p < 0.0001) and the highest (although not statistically significant) sensitivity and specificity above all other parameters tested in discriminating between OAG and ACG eyes. Discrimination criteria revealed a relevant narrowing of the anterior chamber angle region for values below 22° (ACA), 276 μm (AOD) and 2.08 mm (rACD). Digital gonioscopy by means of SL-OCT allowed a non-invasive and objective imaging of the anterior chamber configuration that could be used as a screening method for narrow and occludable angles. The method could contribute to a timely identification of angle closure and alert clinicians to further determine whether a peripheral iridotomy should be performed.

Five-year incidence of angle closure among glaucoma health examination participants

To investigate incidence of angle closure (AC) and its associated factors through a community-based longitudinal study over a 5-year period. Japanese residents aged 40 years or over who underwent two glaucoma health examinations held in 2005 and 2010 were enrolled. Of the participants of the first glaucoma health examination (first examination), those who satisfied exclusion criteria such as having eyes with angle closure, glaucoma, incisional ocular surgery, or other conditions that could influence the results were eliminated from the second glaucoma health examination (second examination). In addition to routine ophthalmic examination, a scanning peripheral anterior chamber depth analyzer (SPAC) was employed to investigate the anterior chamber configuration. The incidence of angle closure over the 5-year period and its associated factors were investigated. Of the 754 participants of the first examination, 569 participants were invited for the second examination and 331 participants (87 males and 244 females, age: 62.6 ± 12.7 years), or 619 eyes, were analyzed after eliminating eyes matching exclusion criteria. In the 5-year period, the incidence of AC was 5.4 % (95 % CI: 3.5-8.4 %) of participants or 5.5 % (95 % CI: 4.0-7.6 %) of eyes, including eight eyes (1.3 %) with primary angle-closure glaucoma. Eyes that developed AC had a much smaller SPAC grade at the first examination and a greater decrease in SPAC grade than those that did not develop AC, whereas age and sex were not associated. AC was developed by 5.4 % of senior Japanese residents over the 5-year period. The shallow anterior chamber and the marked decrease in anterior chamber depth were associated with AC development.

Transient changes of intraocular pressure and anterior segment configuration after diagnostic mydriasis with 1% tropicamide in children

Background: This study investigated the association of transient changes in intraocular pressure (IOP) with changes in the anterior chamber configuration in children after diagnostic mydriasis with 1% tropicamide.Methods: In this prospective case‐control study, 163 hospital clinic‐based samples of unrelated children with or without myopia were enrolled. Complete ophthalmological examinations, including visual acuities, cycloplegic refraction, slitlamp examination, fundus examination, IOP, axial length measurement and Pentacam examination were performed.Results: Lens thickness in emmetropic children was significantly greater than in myopic children of both genders, both before and after mydriasis. In a comparison of the biometric differences before and after mydriasis, IOP was not different, but the lens thickness after mydriasis was significantly less in myopic and emmetropic children of both genders. The mean anterior chamber angle, anterior chamber depth and anterior chamber volume significantly increased after mydriasis in myopic and emmetropic children of both genders. These parameters were not related to the changes of IOP under multiple regression analysis. There were no statistically significant differences between groups in either biometric parameters or anterior chamber configurations.Conclusion: While the present findings do not show a significant change in IOP following mydriasis, there was wide inter‐individual variation, with some children showing an increase in IOP of up to 8.0-mmHg and some showing a decrease of a similar amount. This variation suggests that IOP should be monitored when mydriatics or cycloplegics are used in children.

Anterior Chamber Configuration Changes after Cataract Surgery in Eyes with Glaucoma

PurposeTo evaluate changes in anterior chamber depth (ACD) and angle width induced by phacoemulsification and intraocular lens (IOL) implantation in eyes with glaucoma, using anterior segment optical coherence tomography (AS-OCT).MethodsEleven eyes of 11 patients with angle-closure glaucoma (ACG) and 12 eyes of 12 patients with open-angle glaucoma (OAG) underwent phacoemulsification and IOL implantation. Using AS-OCT, ACD and angle parameters were measured before and 2 days after surgery. Change in intraocular pressure (IOP) and number of ocular hypotensive drugs were evaluated.ResultsAfter surgery, central ACD and angle parameters increased significantly in eyes with glaucoma (p < 0.05). Prior to surgery, mean central ACD in the ACG group was approximately 1.0 mm smaller than that in the OAG group (p < 0.001). Post surgery, mean ACD of the ACG group was still significantly smaller than that of the OAG group. No significant differences were found in angle parameters between the ACG and OAG groups. In the ACG group, postoperative IOP at the final visit was significantly lower than preoperative IOP (p = 0.018) and there was no significant change in the number of ocular hypotensive medications used, although clinically, patients required fewer medications. In the OAG group, the IOP and number of ocular hypotensive drugs were almost unchanged after surgery.ConclusionsThe ACD and angle width in eyes with glaucoma increased significantly after phacoemulsification and IOL implantation. Postoperative ACD significantly differed between the ACG and OAG groups, whereas angle parameters did not differ.

Changes in Anterior Chamber Configuration after Cataract Surgery as Measured by Anterior Segment Optical Coherence Tomography

PurposeTo evaluate the changes in anterior chamber depth (ACD) and angle width induced by phacoemulsification and intraocular lens (IOL) implantation in normal eyes using anterior segment optical coherence tomography (AS-OCT).MethodsForty-five eyes (45 patients) underwent AS-OCT imaging to evaluate anterior chamber configuration before and 2 days after phacoemulsification and IOL implantation. We analyzed the central ACD and angle width using different methods: anterior chamber angle (ACA), trabecular-iris angle (TIA), angle opening distance (AOD), and trabecular iris surface area (TISA) in the nasal and temporal quadrants. Comparison between preoperative and postoperative measurement was done using paired t-tests and each of the angle parameters was analyzed with Pearson correlation testing. Subgroup analyses according to the IOL and axial length were performed with a general multivariate linear model adjusted for age.ResultsBefore surgery, the mean anterior chamber angle widths were 23.21 ± 6.70° in the nasal quadrant and 24.89 ± 7.66° in the temporal quadrant. The mean central ACD was 2.75 ± 0.43 mm. After phacoemulsification and IOL implantation, the anterior chamber angle width increased significantly to 35.16 ± 4.65° in the nasal quadrant (p = 0.001) and 36.03 ± 4.86° in the temporal quadrant (p = 0.001). Also, central ACD increased to 4.14 ± 0.31 mm (p = 0.001). AOD, TISA, and TIA increased significantly after cataract surgery and showed positive correlation with ACA.ConclusionsAfter cataract surgery, the ACD and angle width significantly increased in eyes with cataract. AS-OCT is a good method for obtaining quantitative data regarding anterior chamber configuration.

Anterior Chamber Configuration in Patients with Glaucoma: MR Gonioscopy Evaluation with Half-Fourier Single-Shot RARE Sequence and Microscopy Coil

The purpose of the study was to determine the accuracy of half-Fourier single-shot rapid acquisition with relaxation enhancement high-spatial-resolution magnetic resonance (MR) imaging performed with a microscopy coil in the diagnosis of narrow anterior chamber angle in patients with glaucoma. Slit-lamp biomicroscopy served as the reference standard. The institutional review board approved this study, and written informed consent was obtained from the 20 recruited patients. There was excellent agreement between MR gonioscopy and slit-lamp biomicroscopy in the classification of anterior chamber angles as narrow or open (kappa = 0.89 [95% confidence interval: 0.69, 1.10]). MR gonioscopy has substantial potential as a technique used to evaluate glaucoma.

Study of anterior chamber configuration with panoramic ultrasound biomicroscopy after cataract surgery with phacoemulsification and foldable intraocular lenses implantation

To study the changes in anterior chamber configuration after phacoemulsification and foldable intraocular lenses (IOL) implantation with panoramic ultrasound biomicroscopy (UBM). A novel panoramic UBM was developed for anterior segment scanning. Small-incision phacoemulsification and foldable IOL implantation were performed in 102 eyes of 81 patients with age-related cataract. The anterior chamber diameter in horizontal meridian and vertical meridian and the anterior chamber depth (ACD) were measured by computer calipers before and two months after the surgery. The changes of the anterior chamber angle were measured in 36 eyes. Diameter of anterior chamber in vertical meridian was greater than that in horizontal meridian in most cases. In all patients, horizontal anterior chamber diameter was widened significantly two months after surgery (t = 7.10, P < 0.01), a significantly negative correlation existed between preoperative and postoperative data(r = 0.801, P < 0.01). The ACD was deepened ( t = 39.97, P < 0.01) . In 36 eyes, the anterior chamber angle was widened. Diameter of the anterior chamber in vertical meridian is greater than that in horizontal meridian in most cases. After phacoemulsification and foldable IOL implantation, UBM revealed that the anterior chamber diameter is increased and postoperative chamber diameter can be estimated by preoperative one. After the operation, the iris diaphragm shifts backward, the anterior chamber is deepened and anterior chamber angle is widened.