AIM: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.METHODS:A total of 450 UBM images we...AIM: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.METHODS: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.RESULTS: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 763.688μm and an actual mean value of 776.9304μm.The R²was 0.4456 and the root mean square error was 201.5166.CONCLUSION: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.展开更多
● AIM: To compare the results of 25 MHz and 50 MHz ultrasound biomicroscopy(UBM) regarding the image characteristics of the lens and its related diseases and to discuss the application value of 25 MHz UBM in ophthalm...● AIM: To compare the results of 25 MHz and 50 MHz ultrasound biomicroscopy(UBM) regarding the image characteristics of the lens and its related diseases and to discuss the application value of 25 MHz UBM in ophthalmology.● METHODS: A total of 302 patients(455 eyes) were included in this study from November 2014 to May 2015. Patient ages ranged from 5 to 89 y(mean±SD: 61.0±17.7 y). Different cross-sectional images of the lens were collected to compare and analyze the image characteristics and anterior segment parameters using 25 MHz and 50 MHz UBM in axial and longitudinal scanning modes, respectively. SPSS 19.0 for Windows, paired t-tests and B&A plot analysis were used for data analysis, and a value of P<0.05 was considered statistically significant.● RESULTS: The 25 MHz UBM images displayed the lens shape more clearly than 50 MHz UBM images. Particularly for cataracts, the whole opacity of the lens was shown by 25 MHz UBM, but 50 MHz UBM only showed part of the lens. The means of the anterior segment parameters obtained using 25 MHz and 50 MHz UBM were as follows: central corneal thickness: 0.55±0.03 and 0.51±0.04 mm, respectively; central anterior chamber depth: 2.48±0.54 and 2.56±0.56 mm, respectively; and central lens thickness: 4.26±0.62 and 4.15±0.56 mm, respectively. A statistically significant difference was found between the results obtained with 25 MHz UBM and those obtained with 50 MHz UBM. The two devices had a good agreement in measuring the anterior segment parameters. ● CONCLUSION: The 25 MHz UBM had an obvious advantage in showing the lens shape. It can provide reliable imaging of the lens and its related diseases and has a high application value for ophthalmology.展开更多
AIM:To assess the predictive value of baseline parameters of ultrasound biomicroscopy(UBM) for angle widening after prophylactic laser peripheral iridotomy(LPI) in patients with primary angle-closure suspect(PACS).MET...AIM:To assess the predictive value of baseline parameters of ultrasound biomicroscopy(UBM) for angle widening after prophylactic laser peripheral iridotomy(LPI) in patients with primary angle-closure suspect(PACS).METHODS:Angle-opening distance(AOD),trabecular iris angle(TIA),iris thickness,trabecular-ciliary process angle,and trabecular-ciliary process distance were measured using UBM performed before and two weeks after LPI.Iris convexity(IC),iris insertion,angulation,and ciliary body(CB) size and position were graded.Uni-and multivariate regression analyses were used to determine factors predicting the change in AOD(ΔAOD500,calculated as an angle width change before and after LPI) in all quadrants and in subgroup quadrants based on IC.RESULTS:In 94 eyes of 94 patients with PACS,LPI led to angle widening with increases in AOD500 and TIA(P<0.01).Multivariable regression analysis showed that IC(P<0.001),CB position(P=0.007) and iris insertion(P=0.049) were significantly predictive for ΔAOD500.All quadrants were categorized into extreme IC(27.8%),moderate IC(62.3%),and absent IC(9.9%) subgroups.The AOD500 increased by 220% and no other predictive factor was found in the extreme IC quadrants.The AOD500 increased by 55%,and baseline iris angulation was predictive for smaller changes in ΔAOD500 in the moderate IC quadrants.CONCLUSION:In PACS patients,quadrants with greater iris bowing predict substantial angle widening after LPI.Quadrants with a flatter iris,anteriorly positioned CB,and basal iris insertion are associated with less angle widening after LPI.Quadrants with iris angulation as well as a flatter iris configuration predict a smaller angle change after LPI.展开更多
Aim: In this study we investigated the changes in anterior segment morphology in pseudophakia patients that underwent ultrasound biomicroscopy (UBM) after pars plana vitrectomy (PPV) operation without use of tamponade...Aim: In this study we investigated the changes in anterior segment morphology in pseudophakia patients that underwent ultrasound biomicroscopy (UBM) after pars plana vitrectomy (PPV) operation without use of tamponade. Method: Pseudophakic patients who undergo PPV were enrolled in this prospective study between October 2012 and April 2015. Study included patients in whom intraocular tamponade was not used during PPV operation. UBM measurements were performed both before and 10 days after the operation. Anterior chamber depth (ACD) was measured using axial images of anterior segment. Trabecular meshwork-iris angle (TIA), ciliary body thickness (CBT), sclera thickness (ST), trabecular meshwork-ciliary process distance (T-CPD), iris-ciliary processes distance (I-CPD), and iris thickness (IT) were measured at temporal quadrant based on radial section images of the angle. Values measured before and after the operation were statistically compared with each other. Results: This study included 30 patients (18 females, 12 males) that underwent an operation ultrasound biomicroscopy (UBM) after pars plana vitrectomy (PPV) operation without use of tamponade. Mean age was 69.6 ± 9.1 (55 - 85) years. Eighteen operations occurred on the left eye whereas twelve operations occurred on the right eye. CBT1, CBT2, CBT Max, T-CPD, and I-CPD were significantly decreased after operation when compared with the values of baseline (before) (p = 0.018, p = 0.012, p = 0.001, p = 0.033, p = 0.015, respectively). Other evaluated parameters did not show statistically significant changes after the operation (p > 0.05). Discussion: PPV results in significant changes in ciliary body morphology together with changes in anterior segment parameters in pseudophakic cases.展开更多
·AIM:To compare the ciliary body thickness between eyes with primary angle closure(PAC)and primary angle-closure glaucoma(PACG)with the normal eyes,and to investigate the association between ciliary body thicknes...·AIM:To compare the ciliary body thickness between eyes with primary angle closure(PAC)and primary angle-closure glaucoma(PACG)with the normal eyes,and to investigate the association between ciliary body thickness and ciliary processes situation.·METHODS:In this cross-sectional study,57 patients with PAC/PACG were matched to 57 normal subjects after propensity score matching(PSM)adjusting for age and gender.All subjects underwent conventional ocular examinations and ultrasound biomicroscopy(UBM)examination,among which the patients with PAC/PACG performed the examinations one month after laser peripheral iridotomy(LPI).Quantitative parameters were measured,which included ciliary body thickness at the position of 1 mm posterior to the scleral spur(CBT1),trabecular-ciliary process distance(TCPD)and trabecularciliary process angle(TCA).·RESULTS:Eyes with PAC/PACG presented significantly thinner CBT1,shorter TCPD and smaller TCA(P<0.001)than the normal eyes,both in comparison of the means of four quadrants and in comparisons of each quadrant.After removing images with peripheral anterior synechia(PAS),the same results were also found in comparisons between the two groups.Significant correlations were found between TCPD(R~2=0.537,P<0.001)and TCA(R~2=0.517,P<0.001)with CBT1.·CONCLUSION:Eyes with PAC/PACG have thinner ciliary body thickness and more anteriorly situated ciliary processes.Thinner ciliary body thickness is associated with anterior situation of the ciliary processes.展开更多
·AIM: To evaluate the accuracy of 20 MHz immersion Bscan ultrasonography in observing lens and to investigate the value of this noninvasive preoperative diagnosis method in alkali burn eyes.·METHODS: It was ...·AIM: To evaluate the accuracy of 20 MHz immersion Bscan ultrasonography in observing lens and to investigate the value of this noninvasive preoperative diagnosis method in alkali burn eyes.·METHODS: It was a comparative study. Fifty-six cases(56 eyes) of alkali burn eyes were examined by ultrasound biomicroscopy(UBM) and immersion 20 MHz B-scan ultrasonography from June 2011 to April 2013,the images were analyzed, and the ultrasonographic diagnosis compared with the operation results.·RESULTS: In 56 alkali burn eyes examined by UBM, the lens were not detected in 16 eyes; the IOL could be detected in 2 eyes; the anterior lens capsule surface or/and the front lens could be detected in 18 eyes, and lens opacification in 3 eyes of them; suspected abnormal lens were detected in the other 20 eyes. In all the same eyes examined by immersion 20 MHz B-scan ultrasonography,the lens were not detected in 16 eyes; the IOL could be detected in 2 eyes; 24 abnormal lens(opacity, lens expansion, shrinkage) and 14 normal lens were found.Compared with the intraoperative findings, the diagnostic accordance rate of the immersion 20 MHz B-scan appearance of lens was 100%(56/56), which was significantly higher than examined by UBM 57.14%(32/56)(χ2=30.55, P =0.0000).·CONCLUSION: Immersion 20 MHz B-scan ultrasonography can observe the lens accurately in alkali burn eyes. It has important clinical value to combine with UBM in eyes of alkali burn.展开更多
文摘AIM: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.METHODS: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.RESULTS: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 763.688μm and an actual mean value of 776.9304μm.The R²was 0.4456 and the root mean square error was 201.5166.CONCLUSION: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.
文摘● AIM: To compare the results of 25 MHz and 50 MHz ultrasound biomicroscopy(UBM) regarding the image characteristics of the lens and its related diseases and to discuss the application value of 25 MHz UBM in ophthalmology.● METHODS: A total of 302 patients(455 eyes) were included in this study from November 2014 to May 2015. Patient ages ranged from 5 to 89 y(mean±SD: 61.0±17.7 y). Different cross-sectional images of the lens were collected to compare and analyze the image characteristics and anterior segment parameters using 25 MHz and 50 MHz UBM in axial and longitudinal scanning modes, respectively. SPSS 19.0 for Windows, paired t-tests and B&A plot analysis were used for data analysis, and a value of P<0.05 was considered statistically significant.● RESULTS: The 25 MHz UBM images displayed the lens shape more clearly than 50 MHz UBM images. Particularly for cataracts, the whole opacity of the lens was shown by 25 MHz UBM, but 50 MHz UBM only showed part of the lens. The means of the anterior segment parameters obtained using 25 MHz and 50 MHz UBM were as follows: central corneal thickness: 0.55±0.03 and 0.51±0.04 mm, respectively; central anterior chamber depth: 2.48±0.54 and 2.56±0.56 mm, respectively; and central lens thickness: 4.26±0.62 and 4.15±0.56 mm, respectively. A statistically significant difference was found between the results obtained with 25 MHz UBM and those obtained with 50 MHz UBM. The two devices had a good agreement in measuring the anterior segment parameters. ● CONCLUSION: The 25 MHz UBM had an obvious advantage in showing the lens shape. It can provide reliable imaging of the lens and its related diseases and has a high application value for ophthalmology.
文摘AIM:To assess the predictive value of baseline parameters of ultrasound biomicroscopy(UBM) for angle widening after prophylactic laser peripheral iridotomy(LPI) in patients with primary angle-closure suspect(PACS).METHODS:Angle-opening distance(AOD),trabecular iris angle(TIA),iris thickness,trabecular-ciliary process angle,and trabecular-ciliary process distance were measured using UBM performed before and two weeks after LPI.Iris convexity(IC),iris insertion,angulation,and ciliary body(CB) size and position were graded.Uni-and multivariate regression analyses were used to determine factors predicting the change in AOD(ΔAOD500,calculated as an angle width change before and after LPI) in all quadrants and in subgroup quadrants based on IC.RESULTS:In 94 eyes of 94 patients with PACS,LPI led to angle widening with increases in AOD500 and TIA(P<0.01).Multivariable regression analysis showed that IC(P<0.001),CB position(P=0.007) and iris insertion(P=0.049) were significantly predictive for ΔAOD500.All quadrants were categorized into extreme IC(27.8%),moderate IC(62.3%),and absent IC(9.9%) subgroups.The AOD500 increased by 220% and no other predictive factor was found in the extreme IC quadrants.The AOD500 increased by 55%,and baseline iris angulation was predictive for smaller changes in ΔAOD500 in the moderate IC quadrants.CONCLUSION:In PACS patients,quadrants with greater iris bowing predict substantial angle widening after LPI.Quadrants with a flatter iris,anteriorly positioned CB,and basal iris insertion are associated with less angle widening after LPI.Quadrants with iris angulation as well as a flatter iris configuration predict a smaller angle change after LPI.
文摘Aim: In this study we investigated the changes in anterior segment morphology in pseudophakia patients that underwent ultrasound biomicroscopy (UBM) after pars plana vitrectomy (PPV) operation without use of tamponade. Method: Pseudophakic patients who undergo PPV were enrolled in this prospective study between October 2012 and April 2015. Study included patients in whom intraocular tamponade was not used during PPV operation. UBM measurements were performed both before and 10 days after the operation. Anterior chamber depth (ACD) was measured using axial images of anterior segment. Trabecular meshwork-iris angle (TIA), ciliary body thickness (CBT), sclera thickness (ST), trabecular meshwork-ciliary process distance (T-CPD), iris-ciliary processes distance (I-CPD), and iris thickness (IT) were measured at temporal quadrant based on radial section images of the angle. Values measured before and after the operation were statistically compared with each other. Results: This study included 30 patients (18 females, 12 males) that underwent an operation ultrasound biomicroscopy (UBM) after pars plana vitrectomy (PPV) operation without use of tamponade. Mean age was 69.6 ± 9.1 (55 - 85) years. Eighteen operations occurred on the left eye whereas twelve operations occurred on the right eye. CBT1, CBT2, CBT Max, T-CPD, and I-CPD were significantly decreased after operation when compared with the values of baseline (before) (p = 0.018, p = 0.012, p = 0.001, p = 0.033, p = 0.015, respectively). Other evaluated parameters did not show statistically significant changes after the operation (p > 0.05). Discussion: PPV results in significant changes in ciliary body morphology together with changes in anterior segment parameters in pseudophakic cases.
文摘·AIM:To compare the ciliary body thickness between eyes with primary angle closure(PAC)and primary angle-closure glaucoma(PACG)with the normal eyes,and to investigate the association between ciliary body thickness and ciliary processes situation.·METHODS:In this cross-sectional study,57 patients with PAC/PACG were matched to 57 normal subjects after propensity score matching(PSM)adjusting for age and gender.All subjects underwent conventional ocular examinations and ultrasound biomicroscopy(UBM)examination,among which the patients with PAC/PACG performed the examinations one month after laser peripheral iridotomy(LPI).Quantitative parameters were measured,which included ciliary body thickness at the position of 1 mm posterior to the scleral spur(CBT1),trabecular-ciliary process distance(TCPD)and trabecularciliary process angle(TCA).·RESULTS:Eyes with PAC/PACG presented significantly thinner CBT1,shorter TCPD and smaller TCA(P<0.001)than the normal eyes,both in comparison of the means of four quadrants and in comparisons of each quadrant.After removing images with peripheral anterior synechia(PAS),the same results were also found in comparisons between the two groups.Significant correlations were found between TCPD(R~2=0.537,P<0.001)and TCA(R~2=0.517,P<0.001)with CBT1.·CONCLUSION:Eyes with PAC/PACG have thinner ciliary body thickness and more anteriorly situated ciliary processes.Thinner ciliary body thickness is associated with anterior situation of the ciliary processes.
基金Supported by National Key Basic Research Program of China(973 Program,No.2013CB967001)National Natural Science Foundation of China(No.81271052,No.31271059)
文摘·AIM: To evaluate the accuracy of 20 MHz immersion Bscan ultrasonography in observing lens and to investigate the value of this noninvasive preoperative diagnosis method in alkali burn eyes.·METHODS: It was a comparative study. Fifty-six cases(56 eyes) of alkali burn eyes were examined by ultrasound biomicroscopy(UBM) and immersion 20 MHz B-scan ultrasonography from June 2011 to April 2013,the images were analyzed, and the ultrasonographic diagnosis compared with the operation results.·RESULTS: In 56 alkali burn eyes examined by UBM, the lens were not detected in 16 eyes; the IOL could be detected in 2 eyes; the anterior lens capsule surface or/and the front lens could be detected in 18 eyes, and lens opacification in 3 eyes of them; suspected abnormal lens were detected in the other 20 eyes. In all the same eyes examined by immersion 20 MHz B-scan ultrasonography,the lens were not detected in 16 eyes; the IOL could be detected in 2 eyes; 24 abnormal lens(opacity, lens expansion, shrinkage) and 14 normal lens were found.Compared with the intraoperative findings, the diagnostic accordance rate of the immersion 20 MHz B-scan appearance of lens was 100%(56/56), which was significantly higher than examined by UBM 57.14%(32/56)(χ2=30.55, P =0.0000).·CONCLUSION: Immersion 20 MHz B-scan ultrasonography can observe the lens accurately in alkali burn eyes. It has important clinical value to combine with UBM in eyes of alkali burn.
