Predictive Equation for Angle Opening Distance at 750 μm After Laser Peripheral Iridotomy in Primary Angle Closure Suspects

Aim: The aim of this study was to investigate the changes in anterior segment parameters as assessed by ultrasound biomicroscopy (UBM) after laser peripheral iridotomy (LPI) and to propose a prediction equation for the width of the angle after LPI.Design: This was a prospective study.Participants: The participants included 100 subjects with primary angle closure suspect (PACS).Methods: Anterior segment UBM parameters were measured, whereas AOD750 was chosen to indicate the width of the angle associated with gonioscopic angle closure, as found in a prior study.Main Outcome Measures: Angle parameters, iris parameters, anterior chamber parameters and ciliary body parameters.Results: All angle parameters increased after LPI, including the mean angle opening distance at 750 μm (AOD750), mean angle opening distance at 500 μm from the scleral spur (AOD500), mean angle opening distance at 750 μm from the scleral spur (AOD750), and mean angle recess area at 750 μm from the scleral spur (ARA750). Among iris parameters and ciliary body parameters, the iris thickness at 2,000 μm (IT2000), iris curvature (IC), and trabecular-ciliary process distance (ICPD) were reduced after LPI. The final equation consisted of four parameters: anterior chamber depth (ACD), iris thickness at 750 μm from the scleral spur (IT750), AOD750, and lens vault (LV). This equation explained 42.7% of the variability in the angle opening indicator AOD750 after LPI, whereas in the plateau iris configuration subgroup, the accuracy of the prediction equation reached the highest a maximum of 68.6%.Conclusions: There was an increase in angle opening and iris flattening after LPI. An equation involving four angle parameters was constructed, this equation which could explained 42.7% of the variability in the angle opening indicator AOD750 after LPI whereas in the plateau iris configuration subgroup, the accuracy of the prediction equation reached a maximum of 68.6%.

Ultrasound Biomicroscopy Might Predict the Outcome of Phacoemulsification-Visco Dissection in Medically Controlled Primary Angle-Closure Glaucoma Eye With Extensive Peripheral Anterior Synechia

Objective: The treatment procedures of primary angle-closure glaucoma (PACG) with extensive peripheral anterior synechia (PAS) is a subject of debate. This study is to investigate the clinical features of phacoemulsification (Phaco)-visco dissection in medically controlled PACG patients with PAS > 180° and evaluate the predictability of Ultrasound Biomicroscopy (UBM) parameters on postoperative intraocular pressure (IOP).Methods: 48 eyes (48 patients) with acute angle-closure glaucoma (AACG) and 30 eyes (30 patients) with chronic angle-closure glaucoma (CACG) were prospectively included. All patients underwent phaco-viscogoniolysis and foldable lens implantation and were followed for 1 year after surgery. We analyzed preoperative and postoperative IOP, the numbers of anti-glaucoma medicine, the visual field value, the extent of PAS, and UBM parameters alterations, and evaluated the correlation between preoperative UBM parameters and one-year postoperative IOP.Results: IOP reduced significantly from 16.24 ± 4.33 to 14.49 ± 3.69 mmHg in AACG group and from 16.16 ± 3.69 mmHg to 14.31 ± 4.12 mmHg in CACG group, and PAS decreased significantly from 270 ± 60.33 to 171 ± 56.44° in AACG group and from 285 ± 70.46 to 168 ± 61.32° in CACG group, and the number of anti-glaucoma drugs decreased significantly in both groups. Several UBM parameters, including anterior chamber depth, trabecular iris angle, and peripheral iris thickness 500 increased while iris convex reduced considerably in the two groups, and angle opening distance 500 and trabecular-meshwork ciliary process angle increased significantly only in AACG group. One-year postoperative IOP correlated with preoperative angle opening distance 500 and trabecular iris angle negatively and iris convex positively.Conclusion: Phaco-visco dissection can effectively reduce IOP, the numbers of glaucomatous medications, and PAS in medically controlled PACG patients with extensive PAS. UBM parameters might be valuable for analyzing postoperative anterior segment structure and predicting postoperative IOP of Phaco-visco dissection in PACG patients with extensive PAS.

Biallelic variants in CPAMD8 are associated with primary open-angle glaucoma and primary angle-closure glaucoma

Background/AimsThis study aims to assess the contribution of biallelic CPAMD8 variants in patients with different forms of glaucoma, especially primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG), based on a systematic analysis of exome sequencing (ES).MethodsPotentially pathogenic CPAMD8 variants were selected from the ES data of 5307 subjects with various eye conditions through multiple bioinformatics analyses. Of the 5307 subjects, 1221 probands had different forms of primary glaucoma. The genotype–phenotype correlation was assessed by a systematic review of biallelic CPAMD8 variants that including our data and data from the literature. The expression profile of CPAMD8 in human tissues was determined at the mRNA and protein levels.ResultsBiallelic CPAMD8 variants, including one frameshift and six missense variants, were exclusively present and significantly enriched in patients with glaucoma (one with juvenile open-angle glaucoma (JOAG), two with POAG and two with PACG) compared with none of the 4086 probands with other eye conditions in this cohort (p=4.1E-07). The effect of variants in these patients is relatively mild compared with that reported in patients with anterior segment dysgenesis or primary congenital glaucoma. CPAMD8 mRNA was highly expressed in the optic nerve, ciliary body, retina and iris, whereas the CPAMD8 protein was mainly detected in the nonpigmented epithelium of the iris and ciliary process, determined by immunohistochemistry.ConclusionsThe data from this study not only provide further evidence to support the association of biallelic CPAMD8 variants with JOAG but also suggest that biallelic CPAMD8 variants might be associated with POAG and PACG.

Tittle Page： The ocular biometry characteristics of young patients with primary angle-closure glaucoma

Backgroud: Although Primary angle-closure glaucoma (PACG) mainly occurs in elderly people, diagnosis of PACG in young patients is not uncommon . However, there is no article specialized on the ocular anatomical characteristics in these patients.Methods: In this retrospective, comparative study, patients diagnosed with PACG and recieved ultrasound biomicroscopy (UBM) examination in our department were included. Patients were divided into two groups: a young group comprised of patients aged ≤45 years of age and an old group comprised of patients＞45 years of age. A-scan ultrasonography and ultrasound biomicroscopy (UBM ) were used to measure ocular biometric parameters of patients in the two groups including axial length (AL), lens thickness (LT), central anterior chamber depth (ACD), anterior chamber width (ACW), angle opening distance 500 (AOD500), anterior angle closure 500 (ACA500), iris thickness 1000 mm from the iris root (IT1000), iris thickness 500 mm from the iris root (IT500), trabecular-ciliary process angle (TCPA), trabecular-ciliary process distance (TCPD), scleral– ciliary process angle (SCPA), lens vault (LV), and pupil diameter (PD). Plateau iris (PI) and base iris insertion were determined from UBM images, and the prevalence of PI and base iris insertion were compared between the two groups. The incidence of postoperative malignant glaucoma (MG) was also determined in both groups and ocular anatomical predictors for the development of malignant glaucoma were evaluated in young PACG patients.Results: 115 patients were included into young group and 144 patients were included into old group. The eyes of patients in the young group had shorter TCPD, shorter AL, narrower TCPA and narrower SCPA compared to the eyes of patients in the old group. There were no significant differences in ACD, LT, AL, LV, AOD 500, ACA500, IT500, IT1000, PD or ACW between the two groups. The prevalence of PI was 25.0% in older patients and 66.1% in younger patients (P < 0.001). Significantly more young patients had base iris insertion compared to old patients (P < 0.001). 87 patients in young group and 79 patients in old group underwent trabeculectomy in our department. Among these patients, 21 young patients and 4 old patients developed MG after trabeculectomy (P < 0.001). Conclusions: AL was shorter, the ciliary body was positioned more anteriorly, prevalence of PI was higher, and incidence of postoperative MG was higher in younger PACG patients compared to older PACG patients. Our results suggest that shorter AL, shorter TCPD and narrower TCPA may be predictors for development of malignant glaucoma in young PACG patients after trabeculectomy.

Anterior eye development in the brown anole, Anolis sagrei

BackgroundAnterior eye development has been explored in different vertebrate species ranging from fish to mammals. However, missing from this diverse group is a representative of reptiles. A promising candidate to fill this void is the brown anole, Anolis sagrei, which is easily raised in the laboratory and for which genome editing techniques exist. Here we provide a detailed histological analysis of the development of the anterior structures of the eye in A. sagrei, which include the cornea, iris, ciliary body, lens, trabecular meshwork, and sclera ossicles.ResultsDevelopment of the anterior segment in Anoles proceeds as for other vertebrates with the lens forming first followed by the cornea, then the iris, ciliary body, trabecular meshwork, and sclera ossicles. The onset of these latter structures occurs first temporally than nasally. Unlike the eyes of mammals and birds, anoles possess a remarkably thin cornea, flat ciliary body, and a trabecular meshwork that lacks an obvious Schlemm’s canal.ConclusionsThis study highlights several features present in anoles and represents an important step towards understanding reptile eye development.Key FindingsThe anole cornea epithelium is thin, composed mainly of a single basal cell layer.The ciliary body lacks a ciliary process.Iris and ciliary body formation occur in a spatiotemporal fashion, developing first temporally then nasally.The anole trabecular meshwork is composed of a spongiform tissue and lacks a Schlemm’s canal.

Comparative Study of the Effects of 1% Atropine on the Anterior Segment

Purpose. To investigate the influences of atropine on changes in anterior segment geometry, as measured by ultrasound biomicroscopy in children. Methods. A prospective observational study was performed. Anterior segment parameters were obtained by UBM before and after the instillation of 1% atropine. Univariate linear regression was performed to identify the variables contributing to the changes in the trabecular meshwork-iris angle (TIA). Results. The study included 21 boys and 37 girls with a mean age of 10.79 ± 2.53 years. Anterior chamber parameters including the central anterior chamber depth, TIA, angle opening distance at 500 μm from the scleral spur, iris thickness 750 μm and 1500 μm from the scleral spur, trabecular-ciliary angle (TCA), trabecular-ciliary process distance, sclera-iris angle (SIA), and sclera-ciliary process angle significantly increased after cycloplegia ( P < 0.05 ). In contrast, the lens vault, iris cross-sectional area, and maximum ciliary muscle thickness significantly decreased after cycloplegia. Univariate analysis identified the change in TCA and the change in SIA and the TIA before mydriasis as determinants of the change in TIA. Conclusions. Atropine causes statistically significant changes in various anterior segment parameters in children. The change in anterior chamber angle is associated with the change in TCA and the change in SIA and the TIA before mydriasis.

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.

Role of 25 MHz Ultrasound Biomicroscopy in the Detection of Subluxated Lenses

Background. The purpose of this observational case series study was to investigate the role of 25 MHz ultrasound biomicroscopy (UBM) in detecting subluxated lenses and compare it with 50 MHz UBM. Methods. 45 patients (49 eyes) with suspected subluxation of the lens and 20 normal volunteers (40 eyes) were included. Different cross-sectional images of the lens position were captured in axial and longitudinal scanning modes using 25 and 50 MHz UBM. The main outcome measurements included the linear distance between the lens equator and ciliary process, the difference value (D-value) between the same cross section of the above bilateral linear distance in the normal and the subluxated subjects, the diagnostic accuracy, and the testing times obtained with 25 and 50 MHz UBM. Results. The position of the lens on axial sections could be clearly shown by using 25 MHz UBM. The D-value of the subluxated eyes was 1-2 mm longer than that of the normal ones. There was a statistically significant difference between 25 and 50 MHz UBM in showing subluxation of the lens, the testing time was significantly faster (2.0 min versus 7.5 min), and the diagnostic accuracy was much higher (98.0% versus 71.4%) with 25 versus 50 MHz UBM. Fifteen eyes with slightly subluxated lens were detected by 25 MHz UBM, and only one eye with slight lens subluxation was detected by 50 MHz UBM. Conclusions. The results indicated that 25 MHz UBM has a greater diagnostic value than 50 MHz UBM in verifying the status of the lens subluxation and can provide reliable and quantitative imaging evidence for clinical use. This trial is registered with ChiCTR–DOD –15007603.