Ultrasound Biomicroscopy Images Research Articles

A Bioengineered Cathepsin B-sensitive Gas Vesicle Nanosystem That Responds With Increased Gray-level Intensity of Ultrasound Biomicroscopic Images

ObjectivesThis work aimed to promote the interaction of a modified Gas Vesicle (GV) with Cathepsin B (CTSB) protease and analyzed their backscattered signal by Ultrasound (US). MethodsWe modified the sequence of the gene coding for GvpC to contain a CTSB cleavage and expressed the protein in an Escherichia coli recombinant system. The protein was purified and added to GVs preparations in which the original GvpC was removed (ΔGV), constituting the modified GV (GV*). Western Blot (WB) test was used to compare GVs with GvpC and engineer GvpC at starting (T0) and after 24 hours (T24) reacting with CTSB. A 21 MHz US B-mode and nonlinear contrast-mode (5% total power) imaged US phantoms having samples of GVwt, ΔGV (stripped GV), GV*, and CTSB+GV*. Also, a 21MHz US B-mode imaged US phantoms having a tumor cell line extracellular fraction (TCEF) and the TCEF+GV* sample. A 100% total US power was applied to collapse the GV structure. ResultsIn WB we detected a decrease in engineered GvpC levels 24 h after the incubation of GV* with CTSB, compared to the concentration at T0, suggesting that CTSB cleaved the engineered GvpC. Regions-of-interest over image of phantom cross-sections were determined and the B-mode image mean gray level intensity resulted in a significant (p<0.05) increase comparing CTSB+GV* with PBS (control), GVwt, ΔGV and GV*. Non-linear mode image gray level intensity from CTSB+GV* increased by 11.79, 7.86 and 14.75 dB from samples containing GVwt, ΔGV and GV*, respectively. GV preparations incubated with TCEF and the TCEF+GV* sample showed an increase of 81% in signal compared to TCEF+GVwt. ConclusionsThe increased ultrasound backscattered signal intensity suggests GVs as a potential biosensor for protease activity, possibly aiding the detection of protease-rich tissue regions.

Evaluation of ciliary body cysts in candidates for phakic lens implantation

PurposePhakic lens implantation in the ciliary sulcus of the eye can be complicated by coincident ciliary body cysts (CBC). We developed an ultrasound imaging and mapping protocol for these cysts.MethodsThis is a retrospective case series of all patients who underwent ICL workup at a single institution from April 2015 to October 2019. A standardized ultrasound biomicroscopy (UBM) imaging protocol was developed to screen for CBCs in either the ciliary body or sulcus. The locations and dimensions of all CBCs were graphically represented.ResultsThe prevalence of CBCs in 158 patients undergoing ICL workup was 34.8%. Among the 159 CBCs detected in 55 patients, 83 were in the sulcus (52%) and 76 were restricted to the ciliary body (48%). ICLs were implanted in 40 eyes with CBCs and 3 eyes with CBCs located within the sulcus horizontally required ICL repositioning due to ICL rotation or iris chafing.ConclusionCBCs were incidentally found in 34.8% of patients undergoing ICL workup. ICL implantation was complicated in 3 of the eyes with CBCs in the horizontal sulcus. Although CBCs are not an absolute contraindication for ICL surgery, we recommend preoperative UBM screening of the ciliary sulcus.

Ultrasound biomicroscopy in dogs suggests postoperative ocular hypertension may be associated with ciliary cleft changes related to cataract surgery.

To determine whether novel pre- and postsurgical ultrasound biomicroscopy (UBM) measurements of the canine ciliary cleft (CC) are associated with postoperative ocular hypertension (POH) following cataract surgery and to explore the relationship between intraocular pressure and CC UBM measurements. Following pharmacologic mydriasis, UBM images were obtained from 31 client-owned dogs before elective cataract surgery, immediately postsurgery, and 4 to 6 hours following surgery or while experiencing POH ≥ 25 mm Hg. Presurgery and the pre- to postsurgery change in CC measurements were assessed for association with POH using individual mixed-effects logistic regression models and forward variable selection models. Linear mixed-effects models were used to evaluate the relationship of intraocular pressure to UBM measurements within the same eye across multiple time points. Presurgical measurements were not predictive of POH development. An increase in pectinate ligament distance and CC area from presurgical baseline to immediate postsurgical measurement was associated with reduced odds of developing POH, while increasing CC length (from apex to mid point on the pectinate ligament) from pre- to postsurgery and immature cataracts was associated with increased odds of POH. The change in CC morphology following cataract surgery appears more impactful in the development of POH than individual variations in presurgery CC measurements. Several changes in the CC dimensions following surgery appear associated with POH risk. This understanding of a potential mechanism of POH development opens new avenues for researching preventative measures associated with modifying surgical techniques to influence CC morphology following cataract surgery.

Ultrasound biomicroscopy qualitative and quantitative signs of phacoantigenic uveitis.

To describe the ultrasound biomicroscopy (UBM) diagnostic features in patients suspected of experiencing chronic inflammation due to phacoantigenic uveitis SUBJECTS/METHODS: This single-center study enrolled patients referred to the Uveitis Department of Cleveland Clinic Abu Dhabi for chronic anterior uveitis and traumatic cataract. Patients' demographics, causes and dates of the inciting traumatic event, and ophthalmic findings were recorded. 20-MHz UBM assessment of the status of the anterior capsule and the crystalline lens was performed. Then, cataract surgery was performed using a single technique. Comparison of the anterior capsule and lens status by clinical, UBM, and intraoperative evaluation. Forty eyes with phacoantigenic uveitis were considered. The slit-lamp examination could identify interruption of the anterior capsule in 20% of the eyes and liquefied sinking lens material in 10%. An intra-operative defect in the anterior capsule was documented in 87.5% of eyes. UBM imaging showed anterior capsule irregularity in 63.3% of eyes and confirmed the presence of anterior capsule defects in 47.5% and lens matter herniating into the anterior chamber in 15%. Hypoechogenic lacunae within the cataractous lens were detected in 12.5% of eyes. For UBM, sensitivity and specificity values were 82.86% (95% CI: 66.35-93.44) and 100% (95% CI: 47.82-100), respectively. Positive and negative predictive values for UBM were 100% (95% CI: 88.06-100) and 45.45% (95% CI: 28.69-63.32), respectively. The overall diagnostic accuracy of UBM was 85% [95% CI: 70.16-94.29]. Ultrasound Biomicroscopy (UBM) is essential for assessing suspected anterior capsule ruptures in phacoantigenic uveitis cases.

Lens Thickness in Infants and Children with Cataracts

PurposeThe purpose of this study was to determine the association between lens thickness and cataract in subjects aged 0-5 years. DesignThis was a prospective multi-center case-control study. ParticipantsWe enrolled 118 participants (171 eyes) age 0-5 years old, mean age 14.6 ± 17.0 months, range 0 - 60 months. MethodsLens thickness was measured on 342 ultrasound biomicroscopy (UBM) images. Main Outcome MeasuresLens thickness; feasibility of lens thickness measurement from UBM images ResultsMean lens thickness among non-cataracts was 3.60 ± 0.17 mm, compared to 3.16 ± 0.61 mm among cataracts (p<0.0001). Lens thickness less than 3.5 mm was significantly associated with increased odds of cataract, adjusted OR=5.99 [2.41,14.88] (p=0.0003) among subjects age 0-7 months. Lens thickness was significantly associated with cataract laterality among subjects age 0-7 months (p<0.0001). ConclusionsQuantitative UBM can be used to evaluate lens thickness in infants and children with congenital cataracts. The lens in congenital cataract eyes was thinner than that of controls among infants. Abnormal lens thickness was significantly associated with cataract. Future longitudinal studies will examine the association between lens thickness and post-cataract surgery outcomes.

Characterization of the anterior segment in Trisomy 21-associated cataract using ultrasound biomicroscopy

BackgroundobjectivesTo compare the structural anatomy of the anterior segment in pediatric Trisomy 21 (T21) subjects with and without cataracts to age-matched controls. DesignProspective case-control study. Participants40 subjects (57 eyes) age 0–25 years old (9.1 ± 10.6 years). MethodsThis prospective case-control study evaluated anterior segment measurements from ultrasound biomicroscopy (UBM) imaging on 342 images. ResultsAmong persons with T21 cataract, the iris was significantly thinner than T21 individuals without cataract (0.28 vs 0.32 mm, p = 0.0181). T21/cataract subjects also had significantly thinner lenses than subjects without cataract, regardless of whether they have T21 or are controls (3.1 mm vs 3.5 mm, p = 0.0074).Thinner lens (<3.5 mm) was insignificantly associated with increased odds of cataract (OR = 9.5 [0.872,104], p = 0.065). Thinner iris (<0.32 mm) was associated with increased odds of cataract (OR = 8.4 [1.188, 59.273], p = 0.033). ConclusionsThese findings support the hypothesis that subtle quantitative anatomic variants are present in the anterior eye of individuals with T21. Specific anatomic variants are unique to the presence of cataract among subjects with T21.

Quantitative signs on ultrasound biomicroscopy images associated with the status of silicone oil emulsification within the eye.

Silicone oil (SO) is a commonly used intraocular tamponade in the treatment of rhegmatogenous retinal detachment (RRD). SO emulsification is a common complication after SO injection. This study aimed to investigate correlations between SO emulsification signs on ultrasound biomicroscopy (UBM) and the real number/size of SO droplets. An observational, cross-sectional study. Thirty-five RRD patients (19 males; 35 eyes) who underwent pars plana vitrectomy and SO injection were enrolled in the study. SO emulsification signs on UBM (endothelial deposits, floating droplets, ghost images, hyperoleon, anterior chamber angle impregnation, anterior iris surface impregnation, posterior iris surface impregnation and ciliary body impregnation) were acquired and quantified two days before SO removal, while real number/size of the SO droplets with a diameter in 0.4-20 μm in the first 2 mL washout fluid collected intraoperatively during SO removal were assessed by Coulter counter. Then the correlations between these values were explored. The grade of tissue impregnation and hyperoleon area in the anterior chamber demonstrated significant correlations with the number of large (5-20 μm) SO droplets (r = 0.336; P = 0.048 and r = 0.350; P = 0.039, respectively); however, no significant correlations were observed with the total number of droplets (0.4-20 μm)or the number of small (0.4-5 μm) droplets (both P ＞ 0.05). The UBM quantitative grade of tissue impregnation and hyperoleon area in the anterior chamber could provide a noninvasive overview of the actual degree of SO emulsification before SO removal surgery.

Ultrasound biomicroscopic imaging parameters associated with outcome in equine infectious ulcerative keratitis and stromal abscesses.

To determine the predictive value of corneal ultrasound biomicroscopy (UBM) findings for the outcome of equine corneal disease. 46 horses with a clinical diagnosis of either infectious ulcerative keratitis or stromal abscess. Corneal UBM (VevoMD; UHF70; VisualSonics) of horses with infectious corneal disease presenting to the North Carolina State University Equine Ophthalmology Service from 2019 to 2023 were evaluated. Size and depth of lesion, presence of Descemet membrane disruption (DMD), corneal thickness, and aqueous humor cell counts (AHCC) were assessed. Comparisons of UBM and clinical exam findings, presence of infectious organisms, and outcome (healed or enucleated) were performed. The UBMs from 46 horses were evaluated. Increased AHCC was significantly associated with increased size and depth of corneal lesions on UBM but not with DMD. Deep lesions and DMD were significantly associated with an enucleation outcome. Horses treated with systemic antibiotics had significantly lower AHCC on UBM, but there were no differences in AHCC with the use of other systemic or topical medications. There was no significant correlation between infectious disease results, clinical findings (aqueous flare or cells), outcome, and UBM AHCC. Parameters on UBM, such as depth of lesion, DMD, and AHCC, may be useful diagnostic and prognostic tools to augment the ophthalmic exam of horses with corneal disease. The UBM findings of deep corneal lesions and DMD suggest a poor prognosis and warrant aggressive surgical intervention.

Anterior Chamber Depth and Lens Thickness Measurements in Pediatric Eyes: Ultrasound Biomicroscopy Versus Immersion A-Scan Ultrasonography

ObjectiveTo compare anterior chamber depth (ACD) and lens thickness (LT) measurements by ultrasound biomicroscopy (UBM), A-scan cross vector (CV) overlay with UBM, and immersion A-scan technique in pediatric eyes. MethodsThis prospective comparative cohort study comprised 43 eyes of 25 pediatric participants (mean age: 2.3±2.2 y). UBM and immersion A-scan biometry were performed prior to dilation and intraocular surgery. ACD and LT were measured by UBM image analysis, A-scan CV UBM overlay, and immersion A-scan technique. ResultsACD and LT measurements obtained using immersion A-scan were significantly greater than with UBM image analysis with mean differences of 0.52 mm and 0.62 mm, respectively (p < 0.001). Immersion A-scan and UBM measurements were moderately correlated (r = 0.70 and 0.64, p < 0.001). ACD and LT measurements obtained using CV overlay were not significantly different than UBM measurements and the values were strongly positively correlated (r = 0.95 and 0.93, p < 0.001). ConclusionImmersion A-scan may overestimate ACD and LT compared to UBM in pediatric patients due to oblique placement of the A-scan probe relative to the optical axis. Supplemental use of UBM and/or CV overlay is indicated to improve measurement accuracy in pediatric patients who cannot reliably fixate due to the ability to confirm proper alignment of the probe with the pupil by visualizing the anterior segment.

A Deep Learning Model for Automatically Quantifying the Anterior Segment in Ultrasound Biomicroscopy Images of Implantable Collamer Lens Candidates

ObjectiveThis study aimed to develop and evaluate a deep learning-based model that could automatically measure anterior segment (AS) parameters on preoperative ultrasound biomicroscopy (UBM) images of implantable Collamer lens (ICL) surgery candidates. MethodsA total of 1164 panoramic UBM images were preoperatively obtained from 321 patients who received ICL surgery in the Eye Center of Renmin Hospital of Wuhan University (Wuhan, China) to develop an imaging database. First, the UNet++ network was utilized to segment AS tissues automatically, such as corneal lens and iris. In addition, image processing techniques and geometric localization algorithms were developed to automatically identify the anatomical landmarks (ALs) of pupil diameter (PD), anterior chamber depth (ACD), angle-to-angle distance (ATA), and sulcus-to-sulcus distance (STS). Based on the results of the latter two processes, PD, ACD, ATA, and STS can be measured. Meanwhile, an external dataset of 294 images from Huangshi Aier Eye Hospital was employed to further assess the model's performance in other center. Lastly, a subset of 100 random images from the external test set was chosen to compare the performance of the model with senior experts. ResultsWhether in the internal test dataset or external test dataset, using manual labeling as the reference standard, the models achieved a mean Dice coefficient exceeding 0.880. Additionally, the intra-class correlation coefficients (ICCs) of ALs’ coordinates were all greater than 0.947, and the percentage of Euclidean distance distribution of ALs within 250 μm was over 95.24%.While the ICCs for PD, ACD, ATA, and STS were greater than 0.957, furthermore, the average relative error (ARE) of PD, ACD, ATA, and STS were below 2.41%. In terms of human versus machine performance, the ICCs between the measurements performed by the model and those by senior experts were all greater than 0.931. ConclusionA deep learning-based model could measure AS parameters using UBM images of ICL candidates, and exhibited a performance similar to that of a senior ophthalmologist.

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

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. To investigate the ocular biometric characteristics of eyes with AAC with zonular laxity to further explore the sensitive parameters for preoperative diagnosis. 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. 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 0.19mm. 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%. Binocular difference of ACD, LV in affected eyes, and binocular difference of LV had high efficiency in diagnosing AAC with zonular laxity.

Ultrasound biomicroscopic findings in Fuchs uveitis syndrome: A contralateral eye study

Abstract: PURPOSE: The aim of this study was to determine ultrasound biomicroscopic findings in patients with Fuchs uveitis syndrome (FUS). METHODS: This cross-sectional, contralateral comparative eye study was conducted on patients with unilateral FUS. Both eyes of each patient underwent ultrasound biomicroscopy (UBM) imaging at the 12, 3, 6, and 9-o’clock radial meridians. Ultrasonographic data were collected, including the thickness (mm) of the ciliary body (CB), CB with ciliary processes, and iris thickness at 0.8 mm from the iris root, mid-iris, and iris tip. RESULTS: We enrolled 36 eyes from 18 patients with unilateral FUS, including 10 (55.6%) females, with a mean age of 38.44 ± 9.2 years. The average thickness of CB (P &lt; 0.001), 0.8 mm from the iris root (P = 0.003), mid-iris (P &lt; 0.001), and the iris tip (P &lt; 0.001) was thinner in the affected eyes compared to the fellow eyes of the patients. Analysis of variance analysis showed that differences among all quadrants were not significant in both groups (P &gt; 0.05). CONCLUSION: This study showed that CB and iris thickness were significantly thinner in the affected eyes compared to the fellow eyes of patients with FUS, as assessed using the UBM technique.

Correlation Between Anterior Chamber Angle Status and Limbal Stem Cell Deficiency in Primary Angle-Closure Glaucoma

PurposeTo investigate the correlation between the opening and closing states of anterior chamber angle (ACA) and the density of limbal epithelial basal cells (LEBCs) in subjects with primary angle-closure glaucoma (PACG). DesignCross-sectional observational study. MethodsA total of 54 eyes of 29 patients diagnosed with PACG were included in the study. 54 eyes from normal subjects were included as control. Automatic evaluation system for ultrasound biomicroscopy images of anterior chamber angle was used to assist ophthalmologists in identifying the opening or closing state of ACA, and the in vivo confocal microscopy (IVCM) was used to evaluate the density of LEBCs in different directions. Results1. The average density of LEBCs in the superior, inferior, nasal and temporal limbus of the eyes in the PACG group was lower than that in the control group, and this pattern did not align with the density distribution observed in the control group.2. In the early, moderate and advanced PACG, the density of LEBCs corresponding to the closed angle was lower than that in the control group (P<0.05). Compared with the density of LEBCs corresponding to the closed angle and the open angle, the closed angle of PACG in the early, moderate and advanced stages was less than that in the open angle (P<0.05 in the early and moderate stages; advanced stage P>0.05).3. The basal cell density was processed by dimensionless analysis. In the data calculated by averaging and minimizing, both closed angle dimensionless values were smaller than the open angle (P<0.05).4. Comparative analysis was conducted among the normal, open-angle, and closed-angle conditions in the superior, inferior, nasal, and temporal limbus. In the early stage of PACG, significant differences were observed in 4 limbal regions (P<0.05), while in the moderate PACG stage, this difference was noted in 3 limbal regions (P<0.05). In advanced PACG, 2 limbal regions exhibited significant differences (P<0.05). These findings suggest that during the early PACG stage, angle closure is the predominant influencing factor on LEBCs density, while in the advanced stage, the decrease in density is attributed to a combination of angle closure and the natural progression of the disease. ConclusionThere is a significant correlation between anterior chamber angle status and LEBCs. Advanced PACG and angle closure should be highly suspected of the occurrence of limbal stem cell deficiency (LSCD).

Classifications of anterior segment structure of congenital corneal opacity in infants and toddlers by ultrasound biomicroscopy and slit-lamp microscopic photographs: an observational study

BackgroundThe structural features have an impact on the surgical prognosis for congenital corneal opacity (CCO). The structural classification system of CCO, however, is lacking. Based on data from ultrasound biomicroscopy (UBM) findings in infants and toddlers with CCO, this research proposed a classification system for the anterior segment structure severity.MethodsMedical records, preoperative UBM images and slit-lamp photographs of infants and toddlers diagnosed with CCO at University Third Hospital between December 2018 and June 2022 were reviewed. According to the anterior segment structural features observed in UBM images, eyes were classified as follows: U1, opaque cornea only; U2, central anterior synechia; U3, peripheral anterior synechia combined with angle closure; and U4, aniridia or lens anomaly. The opacity appearance and corneal vascularization density observed in slit-lamp photographs were assigned grades according to previous studies. The extent of vascularization was also recorded. The corresponding intraocular anomaly classifications and ocular surface lesion severity were analysed.ResultsAmong 81 eyes (65 patients), 41 (50.6%) were right eyes, and 40 (49.4%) were left eyes. The median age at examination was 6.91 months (n = 81, 1.00, 34.00). Two (2.5%) of the 81 eyes were classified as U1, 20 (24.7%) as U2, 22 (27.2%) as U3a, 11 (13.6%) as U3b and 26 (32.1%) as U4. Bilateral CCO eyes had more severe UBM classifications (P = 0.019), more severe dysgenesis (P = 0.012) and a larger angle closure (P = 0.009). Eyes with more severe UBM classifications had higher opacity grades (P = 0.003) and vascularization grades (P = 0.014) and a larger vascularization extent (P = 0.001). Eyes with dysgenesis had higher haze grades (P = 0.012) and more severe vascularization (P = 0.003 for density; P = 0.008 for extent), while the angle closure range was related to haze grade (P = 0.013) and vascularization extent (P = 0.003).ConclusionsThis classification method based on UBM and slit-lamp photography findings in the eyes of CCO infants and toddlers can truly reflect the degree of abnormality of the ocular surface and anterior segment and is correlated with the severity of ocular surface anomalies. This method might provide meaningful guidance for surgical procedure design and prognostic determinations for keratoplasty in CCO eyes.

Deep Learning-Based Model for Automatic Assessment of Anterior Angle Chamber in Ultrasound Biomicroscopy.

The goal of the work described here was to develop and assess a deep learning-based model that could automatically segment anterior chamber angle (ACA) tissues; classify iris curvature (I-Curv), iris root insertion (IRI), and angle closure (AC); automatically locate scleral spur; and measure ACA parameters in ultrasound biomicroscopy (UBM) images. A total of 11,006 UBM images were obtained from 1538 patients with primary angle-closure glaucoma who were admitted to the Eye Center of Renmin Hospital of Wuhan University (Wuhan, China) to develop an imaging database. The UNet++ network was used to segment ACA tissues automatically. In addition, two support vector machine (SVM) algorithms were developed to classify I-Curv and AC, and a logistic regression (LR) algorithm was developed to classify IRI. Meanwhile, an algorithm was developed to automatically locate the scleral spur and measure ACA parameters. An external data set of 1,658 images from Huangshi Aier Eye Hospital was used to evaluate the performance of the model under different conditions. An additional 439 images were collected to compare the performance of the model with experts. The model achieved accuracies of 95.2%, 88.9% and 85.6% in classification of AC, I-Curv and IRI, respectively. Compared with ophthalmologists, the model achieved an accuracy of 0.765 in classifying AC, I-Curv and IRI, indicating that its high accuracy was as high as that of the ophthalmologists (p > 0.05). The average relative errors (AREs) of ACA parameters were smaller than 15% in the internal data sets. Intraclass correlation coefficients (ICCs) of all the angle-related parameters were greater than 0.911. ICC values of all iris thickness parameters were greater than 0.884. The accurate measurement of ACA parameters partly depended on accurate localization of the scleral spur (p < 0.001). The model could effectively and accurately evaluate the ACA automatically based on fully automated analysis of UBM images, and it can potentially be a promising tool to assist ophthalmologists. The present study suggested that the deep learning model can be extensively applied to the evaluation of ACA and AC-related biometric risk factors, andit may broaden the application of UBM imaging in the clinical research of primary angle-closure glaucoma.

Vault predicting after implantable collamer lens implantation using random forest network based on different features in ultrasound biomicroscopy images.

To analyze ultrasound biomicroscopy (UBM) images using random forest network to find new features to make predictions about vault after implantable collamer lens (ICL) implantation. A total of 450 UBM images were collected from the Lixiang Eye Hospital to provide the patient's preoperative parameters as well as the vault of the ICL after implantation. The vault was set as the prediction target, and the input elements were mainly ciliary sulcus shape parameters, which included 6 angular parameters, 2 area parameters, and 2 parameters, distance between ciliary sulci, and anterior chamber height. A random forest regression model was applied to predict the vault, with the number of base estimators (n_estimators) of 2000, the maximum tree depth (max_depth) of 17, the number of tree features (max_features) of Auto, and the random state (random_state) of 40.0. Among the parameters selected in this study, the distance between ciliary sulci had a greater importance proportion, reaching 52% before parameter optimization is performed, and other features had less influence, with an importance proportion of about 5%. The importance of the distance between the ciliary sulci increased to 53% after parameter optimization, and the importance of angle 3 and area 1 increased to 5% and 8% respectively, while the importance of the other parameters remained unchanged, and the distance between the ciliary sulci was considered the most important feature. Other features, although they accounted for a relatively small proportion, also had an impact on the vault prediction. After parameter optimization, the best prediction results were obtained, with a predicted mean value of 763.688 µm and an actual mean value of 776.9304 µm. The R2 was 0.4456 and the root mean square error was 201.5166. A study based on UBM images using random forest network can be performed for prediction of the vault after ICL implantation and can provide some reference for ICL size selection.

The morphology of angle dysgenesis assessed by ultrasound biomicroscopy and its relationship with glaucoma severity and mutant genes in Axenfeld-Rieger syndrome.

Axenfeld-Rieger syndrome (ARS), a developmental disorder, involves anterior segment abnormalities and can lead to glaucoma. However, limited research has addressed the ultrasound biomicroscopy (UBM) characteristics of ARS. This study aimed to assess the anterior chamber angle features using UBM in ARS and determine their correlation with glaucoma severity and mutant genes. UBM examination was conducted for 42 patients diagnosed with ARS and glaucoma. The morphology of the anterior chamber angle was classified into 6 types (type A, pure high iris insertion; type B, posterior embryotoxon; type C, iris process; type D, trabecular-iris synechia; type E, peripheral iridocorneal adhesion; type F, goniodysgenesis). Candidate genes were sequenced with next-generation sequencing. Correlations of clinical characteristics with angle dysgenesis types and mutant genes were analyzed. Among the 42 patients recruited, 6 eyes were excluded for poor quality UBM images or lack of glaucoma development. The remaining 78 eyes were categorized into 6 groups according to their dominant type of anterior chamber angle (>2 quadrants). There were statistically significant differences in onset age of glaucoma (P<0.001), untreated intraocular pressure (IOP) (P=0.016), vertical cup to disc ratio (P=0.001), and age at surgery (P<0.001) among the groups. Eyes in the type C and D groups developed glaucoma and underwent surgery at an earlier age, while eyes in the type B, E, and F groups developed glaucoma at a relatively later age. Eyes in type A group developed glaucoma and underwent surgery at the latest age, and had the lowest untreated IOP compared to the other groups. Patients with FOXC1 defects were more likely to have angle type B, type C, and type D (accounting for 93.8% of the total), whereas patients with PITX2 defects were more likely to have angle type A, type E, and type F (accounting for 92.1% of the total). UBM is powerful for evaluating the anterior segment abnormalities in ARS. Combined with genetic testing results, the morphological classification helps to assess the severity of glaucoma.

The Diagnostic Value of Ultrasound Biomicroscopy in Anterior Segment Diseases.

The purpose of this study was to analyze the use of ultrasound biomicroscopy (UBM) in the diagnosis and follow-up anterior segment diseases. The records of patients who presented to our clinic for UBM between January 1, 2004, and December 31, 2018 were reviewed retrospectively. Demographic characteristics, indications for UBM imaging and findings of the patients were recorded. Also, the change in clinical indications over the years were analyzed. The study included 1.256 eyes of 917 patients, of whom 723 (57.6%) were female and 533 (42.4%) were male. The mean age was 48.7±14.8 years (range: 12-85 years). Indications for UBM imaging were to evaluate glaucoma pathogenesis and surgical outcomes (n=764, 60.8%), iris and ciliary body masses (n=263, 20.9%), congenital anomalies of the crystalline lens and complications of cataract surgery (n=86, 6.8%), the etiology of hypotony (n=57, 4.5%), corneal diseases (n=46, 3.7%), anterior segment findings after trauma (n=22, 1.8%), conjunctival pathologies (n=11, 0.9%), and scleral pathologies (n=7, 0.6%). In patients with glaucoma, the most common reason for requesting UBM according to years was to investigate the plateau iris configuration. UBM is an important imaging method used in the determination of the pathophysiology of anterior segment diseases, clinical evaluation, planning of surgical treatment and analyzing the outcomes.

Intraocular medulloepithelioma clinical features and management of 11 cases

AimsTo describe the clinical features, imaging characteristics, histopathology, treatment and outcomes of intraocular medulloepithelioma.MethodsMedical records of 11 patients with clinically or histopathologically confirmed medulloepithelioma were retrieved and reviewed. Clinical features,...

The Agreement of the Nomogram Tool and Ultrasound Biomicroscopy Images in Calculating Ultrasound Cycloplasty Probe Model in Chinese Patients

Purpose: The aim of the study was to compare and explore the agreement between the nomogram tool and ultrasound biomicroscopy (UBM) images method to calculate the ultrasound cycloplasty (UCP) probe model in Chinese glaucoma patients. Methods: Retrospective analysis of Chinese glaucoma patients who visited Zhongshan Ophthalmic Center in Guangzhou from January to December 2019 and were eligible for UCP surgery. Visual acuity, intraocular pressure (IOP), ocular axial length (AL), and horizontal corneal diameter (white to white [WTW]) were measured. UBM images with clear ciliary body imaging and AL and WTW data were sent to trained personnel for probe model measurements. The data calculated by both methods were analyzed using unweighted and weighted κ statistics. The level of agreement refers to Landis and Koch’s guideline for the strength of agreement indicated with weighted κ values. Results: 1,061 eyes of 642 patients were involved, with a mean age of 61.66 ± 11.66 years. Their best-corrected visual acuity converted to logarithm of minimal-angle-of-resolution (logMAR) scores of −0.18–3.00 with a mean value of 0.69 ± 0.77. IOP was 22.0–60.0 mm Hg with a mean of 27.97 ± 5.66 mm Hg. The mean AL and WTW were 22.88 ± 1.33 (19.15–32.14) mm and 11.52 ± 0.49 (10.00–12.90) mm, respectively. The agreement between the two methods was fair (weighted κ = 0.299), matching in 62.86% of eyes (weighted κ = 0.299, κ = 0.264). The agreement in primary open angle glaucoma, acute primary angle-closure glaucoma, chronic primary angle-closure glaucoma, and secondary glaucoma patients was 60.85% (weighted κ = 0.336, κ = 0.301), 65.06% (weighted κ = 0.146, κ = 0.127), 62.26% (weighted κ = 0.204, κ = 0.184), and 57.97% (weighted κ = 0.332, κ = 0.280) of eyes, respectively. Conclusion: The agreement between UBM images and the nomogram tool to calculate the UCP probe model of Chinese patients is at a fair level. The nomogram tool prefers to use larger probes. Improvements to the nomogram tool, such as including data from more ethnic groups and being able to calculate separately for different types of glaucoma, are needed to improve accuracy. The inclusion of parameters or images from more directions of the eye may help measure probe models more accurately for both the nomogram tool and the UBM image measurement.