Characteristic Manifestations regarding Ultrasound Biomicroscopy Morphological Data in the Diagnosis of Acute Angle Closure Secondary to Lens Subluxation

Ocular manifestations for misdiagnosing acute angle closure secondary to lens subluxation

Introduction

The objective of this study was to assess the clinical characteristics and biometric parameters, as measured by the IOLMaster, of patients suffering from acute secondary angle closure due to zonular dialysis (ASAC-ZD) who were misdiagnosed with acute primary angle closure (APAC).

Methods

In this retrospective study, 34 ASAC-ZD and 39 APAC eyes were examined. Sex, age, best-corrected visual acuity, axial length (AL), anterior chamber depth (ACD), anterior chamber depth standard deviation (ACDSD), lens thickness (LT), and lens thickness standard deviation (LTSD) were measured using the IOLMaster and compared between the two groups. In addition, the difference in ACD (ACD difference) between the affected eye and the contralateral eye was analyzed. Logistic regression analysis was performed to determine the predictive factors of lens subluxation. To determine the appropriate cutoff values for biometric parameters, ROC curves were constructed to distinguish between ASAC-ZD, APAC, and cataracts.

Results

Compared to the APAC group, the ASAC-ZD group was younger (69.92 ± 9.345, 63.74 ± 6.947), had longer AL (22.39 ± 0.7852, 23.23 ± 1.168), shallower ACD (2.120 ± 0.2986, 1.889 ± 0.5167), higher ACDSD (7.605 ± 5.425, 9.941 ± 6.120), higher LTSD (28.00 ± 19.52, 39.79 ± 22.74), and larger ACD differences (-0.1249 ± 0.2349, -0.7306 ± 0.5332) in the affected eye. Younger age, longer AL, lower ACD, higher LTSD, and higher ACD differences were associated with lens subluxation in the univariate logistic regression analysis. ACD difference (p = 0.0003), age (p = 0.0024), and ACD (p = 0.0491) were significantly associated with lens subluxation in the multivariable logistic regression analysis. Furthermore, the ROC curve analysis showed that the cutoff values for lens subluxation were a difference in ACD of 0.225 mm and 1.930 mm.

Conclusion

Asymmetric ACD in both eyes with normal AL and increasing ACDSD and LTSD may support the clinical diagnosis of lens subluxation.

Ocular Biometric Characteristics in Preoperative Diagnosis of Acute Angle Closure With and Without Zonular Laxity

PRCIS

Biometric parameters, including binocular difference of anterior chamber depth (ACD), lens vault (LV) in affected eyes, and binocular difference of the LV, had high efficiency in diagnosing acute angle closure (AAC) with zonular laxity.

PURPOSE

To investigate the ocular biometric characteristics of eyes with AAC with zonular laxity to further explore the sensitive parameters for preoperative diagnosis.

METHODS

This study included 50 patients with AAC with zonular laxity and 54 patients with AAC without zonular laxity. Demographic data, ocular examination results, and biometric parameters on ultrasound biomicroscopy images were compared between the affected and fellow eyes in 2 groups. Parameters significant in the multiple linear regression model were included in a regression equation and the diagnostic efficiency was evaluated by area under the curve.

RESULTS

In patients with AAC with zonular laxity, the binocular difference of central ACD, LV in affected eyes, and binocular difference of the LV were significantly larger than those in patients without zonular laxity respectively and these three parameters were all significant in multiple linear regression analysis (all P <0.001). The area under the curve of binocular difference of ACD, LV in affected eyes, and binocular difference of LV were 0.972, 0.796, and 0.855, respectively, with the cutoff values of 0.23, 1.28, and 0.19 mm. The regression equation containing these three parameters was: ln ( P /(1- P ))=-4.322 + 1.222 [LV in affected eyes (mm)] + 3.657 [binocular difference of LV (mm)] + 6.542 [binocular difference of ACD (mm)], with the accuracy of prediction reaching 94.05%.

CONCLUSION

Binocular difference of ACD, LV in affected eyes, and binocular difference of LV had high efficiency in diagnosing AAC with zonular laxity.

Novel diagnostic indicators for acute angle closure secondary to lens subluxation based on anterior segment and lens parameters

Purpose: To explore stable and sensitive indicators for clinical diagnosis of acute angle closure (AAC) secondary to lens subluxation (LS) through quantitative analysis of CASIA 2 imaging.Design: A prospective cross-sectional study.

Methods

Setting: Clinical practice.Participants: 23 patients with unilateral acute angle closure secondary to lens subluxation and 23 cataract patients without lens subluxation were recruited. Lens subluxation was confirmed by ultrasound biomicroscope diagnosis. The contralateral eyes without LS served as fellow control group. The cataract eyes without LS were enrolled in blank control group.Intervention: Participants underwent ophthalmologic examinations including slit-lamp biomicroscope, best corrected visual acuity, intraocular pressure, central corneal thickness measurement, axial length, gonioscopy, ultrasound biomicroscope and 360-degree anterior chamber and crystalline lens scan protocols of CASIA 2 system.Main outcome measures: Automated circumferential anterior segment and lens morphological parameters under anterior segment optical coherence tomography were analyzed via three-dimensional analysis.

Results

Significant differences were found in the front and back radius of the lens, the front and back radius of steep curvature of the lens, lens thickness, lens decentration, lens diameter, iris-trabecular contact (ITC) index, ITC area, anterior chamber depth (ACD), lens vault (LV), and iris volume between LS and controls. Among these parameters, LV, the anterior radius of steep curvature of the lens and ACD demonstrated the highest prediction power (AUC = 0.87, 0.89, and 0.86, respectively). The prediction power of tilt/axis was much higher in the Gaussian Naive Bayes model (AUCs = 0.90) than in the logistic model (AUCs = 0.74). Combination of LV_mean, LV_std, tilt and tilt axis in Gaussian Naive Bayes model presented as most stable and excellent diagnostic markers for AAC secondary to LS (AUCs = 0.98).

Conclusions

The combination of markers including lens tilt and lens vault in the mathematic model facilitate clinical work as it not only provides novel diagnostic indications and possible prompt treatment for AAC secondary to lens subluxations, but also enhances our understanding of the pathogenic role of zonulopathy in angle closure glaucoma.

Imaging analysis of the biological parameters of the lens in patients with cortical age-related cataracts using ultrasound biomicroscopy

BACKGROUND

The spatial position of the lens in patients with cortical age-related cataract (CARC) is unclear. We investigated a basis for the assessment of visual quality after cataract surgery by analysing the ultrasound biomicroscopic characteristics of the biological parameters of the lens in patients with CARC.

METHODS

In this retrospective study, 119 patients (50 males and 69 females, totalling 238 eyes) with CARC who underwent simple cataract surgery were selected. The lens thickness (LT), axial length (AL), anterior chamber depth (ACD), lens vault (LV), trabecular-iris angle (TIA), iris-lens angle (ILA), iris-lens contact distance (ILCD) were measured by A-scan ultrasound and ultrasound biomicroscopy. The corresponding lens position (LP) and relative lens position (RLP) were calculated.

RESULTS

LP was greater in men than in women (P < 0.05), LV was smaller in men than in women (P = 0.002), ILA and ILCD were not statistically significant (P = 0.072 and P = 0.854, respectively). There were significant differences in TIA, ILA, and ILCD in the four quadrants (all P < 0.05), with a trend in the distribution of TIA: superior < inferior < nasal < temporal, ILA: nasal < inferior < temporal < superior, and ILCD: superior < temporal < inferior < nasal.

CONCLUSIONS

The lens protrudes more obviously in females than in males and the lens tilts to a certain extent with the increase of age and tends to be more upward and temporal in the supine position. Therefore, trends in lens-related parameters in patients with CARC should be taken seriously.

Differences Between Angle Configurations in Different Body Positions by Ultrasound Biomicroscopy in Patients with Cortical Age-Related Cataract

Purpose

To investigate the differences in parameters related to angle configuration and lens position in patients with cortical age-related cataract by ultrasound biomicroscopy (UBM) in different body positions.

Methods

Prospective study with 55 patients with cortical age-related cataract proposed for phacoemulsification, examined using a Compact Touch STS UBM (Quantel Medical, France). UBM bag/balloon technology was applied to measure the central anterior chamber depth (ACD) and lens vault (LV) in horizontal and vertical orientation in sitting and supine positions, angle opening distance (AOD500), trabecular iris angle (TIA) and iris lens angle (ILA) in four quadrants: superior, inferior, nasal, and temporal.

Results

We found no significant difference in ACD between sitting and supine positions (p = 0.053); LV was significantly greater in the supine position (p < 0.001); AOD500 in superior and inferior quadrants were significantly longer in the sitting position (p = 0.001; p < 0.001); TIA in superior and inferior quadrants was significantly greater in the sitting position (p < 0.001; p < 0.001), and TIAmax-min was significantly smaller in the sitting position (p = 0.001); ILA in temporal quadrant was significantly larger in the sitting position (p = 0.015) and ILAmax-min was significantly smaller in the sitting position (p < 0.001).

Conclusion

The anterior chamber angle was narrower and the lens was positioned more anteriorly in the supine than in the sitting position in cortical age-related cataract. Different positions may affect the angle configuration and the relative space of lens through different directions of mechanics and modes of action.

Classifications of Qualitative Characteristics on Angle Configurations via Ultrasound Biomicroscopy in Acute Primary Angle Closure

Purpose

To study the classifications of qualitative characteristics on the angle configurations in the acute primary angle closure (APAC) and fellow eyes by ultrasound biomicroscopy (UBM).

Methods

A total of 131 patients (262 eyes) were researched retrospectively. The qualitative parameters from UBM images were classified into iris form (IF), ciliary body configuration (CBC), basal iris thickness (BIT), iris convexity (IC), iris insert (II), iris angulation (IA), ciliary body size (CBS) and ciliary body position (CBP). Comparative analyses between the APAC (case group) and fellow (control group) eyes were performed.

Results

There were significant differences in IF, CBC, IC, II, CBS, CBP between the case group and control group in all quadrants (P<0.001). The IA of the case group and control group presented significant difference in all quadrants (P=0.001). However, there was not a significant difference in BIT between the case group and control group in all quadrants (P=0.495). The case group had fewer parallelogram-like and mushroom-like and more cone-like and hook-like CBCs than the control group (P<0.001).

Conclusion

Multiple ciliary body configurations can influence the stability of the lens and the anatomic configuration of the anterior chamber angle indirectly. New qualitative classification system of UBM may be more intuitionistic and refined to reflect the angle configurations to help clinical practice.

Characteristics of the Ciliary Body in Healthy Chinese Subjects Evaluated by Radial and Transverse Imaging of Ultrasound Biometric Microscopy

Background: The imaging and analysis of the ciliary body (CB) are valuable in many potential clinical applications. This study aims to demonstrate the anatomy characteristics of CB using radial and transverse imaging of ultrasound biometric microscopy (UBM) in healthy Chinese subjects, and to explore the determining factors. Methods: Fifty-four eyes of 30 healthy Chinese subjects were evaluated. Clinical data, including age, body mass index (BMI), intraocular pressure (IOP), axial length (AL), and lens thickness (LT), were collected. Radial and transverse UBM measurements of the ciliary body were performed. Anterior chamber depth (ACD), ciliary sulcus diameter (CSD), ciliary process length (CPL), ciliary process density (CPD), ciliary process area (CPA), ciliary muscle area (CMA), ciliary body area (CBA), ciliary body thickness (CBT0, CBT1, and CBTmax), anterior placement of ciliary body (APCB), and trabecular-ciliary angle (TCA) of four (superior, nasal, inferior, and temporal) quadrants were measured. Results: The average CPL was 0.513 ± 0.074 mm, and the average CPA was 0.890 ± 0.141 mm2. CPL and CPA tended to be longer and larger in the superior quadrant (p < 0.001) than in the other three quadrants. Average CPL was significantly correlated with AL (r = 0.535, p < 0.001), ACD (r = 0.511, p < 0.001), and LT (r = −0.512, p < 0.001). Intraclass correlation coefficient (ICC) scores were high for CPL (0.979), CPD (0.992), CPA (0.966), CMA (0.963), and CBA (0.951). Conclusions: In healthy Chinese subjects, CPL was greatest in the superior quadrant, followed by the inferior, temporal, and nasal quadrants, and CPA was largest in the superior quadrant, followed by the tempdoral, inferior, and nasal quadrants. Transverse UBM images can be used to measure the anatomy of the ciliary process with relatively good repeatability and reliability.

Ocular Manifestations of Acute Secondary Angle Closure Associated With Lens Subluxation

Purpose:

To evaluate the clinical characteristics and ocular features of patients with acute secondary angle closure, associated with lens subluxation (ASAC-LS).

Methods:

We performed a retrospective study at the EENT Hospital of Fudan University, Shanghai, China. A total of 41 affected eyes from 41 patients were enrolled in this study. Furthermore, 20 affected eyes were part of the ASAC-LS cohort and 21 affected eyes were included in the acute primary angle closure (APAC) cohort. The best-corrected visual acuity (BCVA), intraocular pressure (IOP), axial length (AL), minimum corneal curvature (K1), maximum corneal curvature (K2), and anterior chamber depth (ACD) were measured and compared between the 2 cohorts. In addition, inter-eye (intraindividual) comparison was performed.

Results:

The ASAC-LS cohort exhibited younger ages, more frequent trauma history (35%), lower IOP (27.43 ± 13.86 mmHg vs. 41.27 ± 10.36 mmHg), longer AL (23.96 ± 2.60 vs. 22.49 ± 0.77 mm), shallower ACD (1.28 ± 0.38 vs. 1.58 ± 0.23 mm), and bigger ACD differences (0.99 ± 0.52 vs. 0.15 ± 0.19 mm), as compared with the APAC cohort (all p < 0.05). Moreover, eyes from the lens subluxation cohort experienced worse BCVA, higher IOP, and shallower ACD than their matched unaffected eyes (all p < 0.05). Although longer AL, shallower ACD, and bigger ACD differences were strongly correlated with lens subluxation in a univariate logistic regression analysis, only the ACD difference remained significant in the multivariate model (p = 0.004, OR = 1,510.50). Additionally, according to the receiver operating characteristic (ROC) curve analysis, both ACD and ACD differences had greater value in the differential diagnosis of ASAC-LS and APAC, with a cut-off value of 1.4 and 0.63 mm, respectively.

Conclusions:

Shallower ACD and larger ACD differences provide the promising diagnostic potential for patients with ASAC-LS.

Comparison of Ocular Morphological Parameters Related to Lens Position by Anterior Segment Optical Coherence Tomography and Ultrasound Biomicroscopy

OBJECTIVE

The objective is to compare parameters related to lens position measured using anterior segment optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM) in patients with senile cataract and perform a consistency analysis.

METHODS

This prospective study included 102 patients (102 eyes) scheduled for simple cataract surgery. Among the total patients, 44 were men, and 58 were women. AS-OCT (sitting) and UBM (lying) were used to measure the anterior chamber depth (ACD) in horizontal and vertical orientations and the iris-lens contact distance (ILCD) and iris-lens angle (ILA) in inferior, superior, nasal, and temporal quadrants. Paired-sample t-test was used to compare ACD, ILCD, and ILA measurements of the two methods, while Pearson's linear correlation and Bland-Altman analyses were used to analyze the correlation and consistency of the two results.

RESULTS

The horizontal (2.499 ± 0.464 mm) and vertical (2.531 ± 0.463 mm) ACD measured using AS-OCT and the horizontal (2.556 ± 0.467 mm) and vertical (2.563 ± 0.479 mm) ACD measured using UBM were significantly different (P < 0.001); moreover, the results showed good correlation and agreement. A significant difference was observed between the two methods in terms of ILCD measured in inferior, superior, nasal, and temporal quadrants (P < 0.001), and a significant correlation was found between measurements of both methods (P < 0.001). Approximately 3.92% (4/102), 0.98% (1/102), 3.92% (4/102), and 2.94% (3/102) of points were outside the 95% limits of agreement in the four quadrants, respectively, and the agreement of the results was good. ILA measured using both methods differed in inferior, superior, nasal, and temporal quadrants (P=0.003, 0.011, 0.001, 0.001, respectively), and the correlation was good (P < 0.001). The percentage of points outside the 95% limit was higher in inferior, superior, nasal, and temporal quadrants (4.90% (5/102), 5.88% (6/102), 5.88% (6/102), and 6.86% (7/102)) with poor agreement of the results.

CONCLUSIONS

The correlation between AS-OCT and UBM in terms of measuring lens position-related parameters was good, but the agreement was unstable. The differences in measurement position (sitting and supine) and/or measurement methods (optics and ultrasound) may lead to variability in results.

Exploring the Occurrence Mechanisms of Acute Primary Angle Closure by Comparative Analysis of Ultrasound Biomicroscopic Data of the Attack and Fellow Eyes

Purpose

To explore the anatomical characteristics and occurrence mechanisms of acute primary angle closure (APAC) by comparing the quantitative data of UBM images of the APAC and fellow eyes.

Methods

131 patients (262 eyes) were studied over five years by retrospective analysis. The quantitative data from UBM images including angle opening distance at 500 μm (AOD500), trabecular-iris angle (TIA), iris convexity (IC), iris span (IS), iris-lens angle (ILA), iris-lens contact distance (ILCD), iris-ciliary process angle (ICPA), and limbus-ciliary body angle (LCBA) were retrospectively recorded; comparative analysis of the APAC and fellow eyes was performed.

Results

The superior, inferior, nasal, temporal, and mean AOD500, TIA, IC, and LCBA (P < 0.001) were significantly smaller in APAC than in fellow eyes. Values of the lens thickness (LT), lens/axial length factor (LAF), lens position (LP), and relative lens position (RLP) were lower in APAC than in fellow eyes (P = 0.021; P = 0.025; P < 0.001; and P < 0.001). In APAC eyes, AOD500 was significantly positively correlated with IC, ILCD, and LCBA; TIA was significantly positively significantly correlated with IC, ILCD, and LCBA. In fellow eyes, AOD500 was significantly negatively correlated with ILA and significantly positively correlated with ILCD, ICPA, LCBA, axial length (AL), central anterior chamber depth (CACD), and LP; TIA was significantly negatively correlated with ILA and significantly positively correlated with IS, ILCD, ICPA, LCBA, AL, CACD, LP, and RLP.

Conclusions

Multiple nonpupillary block factors (plateau iris, anterior attachment and insertion of the iris root, anterior shift of the lens, and anterior rotation of the ciliary body) promote the occurrence of APAC, and abnormal positional relationships of the iris, ciliary body, and lens may contribute to APAC.