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1.
Ophthalmologica ; 247(2): 118-132, 2024.
Article in English | MEDLINE | ID: mdl-38408445

ABSTRACT

INTRODUCTION: The objective of this study was to compare the outcome of submacular hemorrhage (SMH) displacement using pneumatic displacement with intravitreal expansile gas versus pars plana vitrectomy (PPV) with subretinal injection of tissue plasminogen activator (tPA), anti-vascular endothelial growth factor (VEGF) agent, and air as primary surgery. METHODS: Retrospective interventional case series of 63 patients who underwent surgical displacement of SMH secondary to neovascular age-related macular degeneration (nAMD) or polypoidal choroidal vasculopathy (PCV) from May 1, 2015, to October 31, 2022. Medical records were reviewed for diagnosis, logMAR visual acuity (VA), central subfield thickness (CST), and postoperative displacement rates and complications up to 12 months after operation. RESULTS: The diagnosis was nAMD in 24 (38.1%) and PCV in 39 (61.9%) eyes. There were 40 (63.5%) eyes in the pneumatic displacement group (38 received C3F8, 2 received SF6) and 23 (36.5%) eyes in the subretinal cocktail injection. Mean baseline VA was 1.46 and 1.62, respectively (p = 0.404). The subretinal injection group had more extensive SMH (p = 0.005), thicker CST (1,006.6 µm vs. 780.2 µm, p = 0.012), and longer interval between symptom and operation (10.65 vs. 5.53 days, p < 0.001). The mean postoperative VA at 6 months was 0.67 and 0.91 (p = 0.180) for pneumatic displacement and subretinal injection groups, respectively, though VA was significantly better in the pneumatic group at 12-month visit (0.64 vs. 1.03, p = 0.040). At least 10 mean change in VA were >10 letters gain in both groups up to 12 months. Postoperative CST reduction was greater (625.1 µm vs. 326.5 µm, p = 0.008) and complete foveal displacement (87.0% vs. 37.5%), p < 0.001, odds ratio [OR] = 11.1) and displacement to arcade or beyond (52.5% vs. 17.5%, p = 0.009, OR = 5.15) were more frequent in the subretinal injection group. Two patients with failed pneumatic displacement were successfully treated with subretinal cocktail injection as a second operation. CONCLUSION: Surgical displacement of SMH leads to clinically meaningful improvement in VA. PPV with subretinal cocktail injection is more effective than pneumatic displacement in displacing SMH with similar safety profile despite longer interval before operation, higher CST, and more extensive SMH at baseline. Retinal surgeons could consider this novel technique in cases with thick and extensive SMH or as a rescue secondary operation in selected cases.


Subject(s)
Endotamponade , Fluorescein Angiography , Retinal Hemorrhage , Tissue Plasminogen Activator , Tomography, Optical Coherence , Visual Acuity , Vitrectomy , Humans , Retrospective Studies , Retinal Hemorrhage/diagnosis , Retinal Hemorrhage/therapy , Retinal Hemorrhage/etiology , Male , Female , Vitrectomy/methods , Aged , Endotamponade/methods , Tissue Plasminogen Activator/administration & dosage , Tomography, Optical Coherence/methods , Fluorescein Angiography/methods , Intravitreal Injections , Angiogenesis Inhibitors/administration & dosage , Follow-Up Studies , Treatment Outcome , Wet Macular Degeneration/diagnosis , Wet Macular Degeneration/therapy , Wet Macular Degeneration/complications , Fundus Oculi , Fibrinolytic Agents/administration & dosage , Fluorocarbons/administration & dosage , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Aged, 80 and over , Middle Aged , Sulfur Hexafluoride/administration & dosage
2.
Retina ; 42(1): 184-194, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34432726

ABSTRACT

PURPOSE: We aimed to develop and test a deep-learning system to perform image quality and diabetic macular ischemia (DMI) assessment on optical coherence tomography angiography (OCTA) images. METHODS: This study included 7,194 OCTA images with diabetes mellitus for training and primary validation and 960 images from three independent data sets for external testing. A trinary classification for image quality assessment and the presence or absence of DMI for DMI assessment were labeled on all OCTA images. Two DenseNet-161 models were built for both tasks for OCTA images of superficial and deep capillary plexuses, respectively. External testing was performed on three unseen data sets in which one data set using the same model of OCTA device as of the primary data set and two data sets using another brand of OCTA device. We assessed the performance by using the area under the receiver operating characteristic curves with sensitivities, specificities, and accuracies and the area under the precision-recall curves with precision. RESULTS: For the image quality assessment, analyses for gradability and measurability assessment were performed. Our deep-learning system achieved the area under the receiver operating characteristic curves >0.948 and area under the precision-recall curves >0.866 for the gradability assessment, area under the receiver operating characteristic curves >0.960 and area under the precision-recall curves >0.822 for the measurability assessment, and area under the receiver operating characteristic curves >0.939 and area under the precision-recall curves >0.899 for the DMI assessment across three external validation data sets. Grad-CAM demonstrated the capability of our deep-learning system paying attention to regions related to DMI identification. CONCLUSION: Our proposed multitask deep-learning system might facilitate the development of a simplified assessment of DMI on OCTA images among individuals with diabetes mellitus at high risk for visual loss.


Subject(s)
Deep Learning , Fluorescein Angiography/methods , Ischemia/diagnosis , Retinal Diseases/diagnosis , Retinal Vessels/diagnostic imaging , Tomography, Optical Coherence/methods , Diabetic Retinopathy/diagnosis , Female , Follow-Up Studies , Fundus Oculi , Humans , Male , Middle Aged , Retrospective Studies
3.
Asia Pac J Ophthalmol (Phila) ; 11(3): 258-266, 2022 May 01.
Article in English | MEDLINE | ID: mdl-34923520

ABSTRACT

PURPOSE: Picture archiving and communication system (PACS) is a medical imaging system for sharing, storage, retrieval, and access of medical images stored. Our study aimed to identify ophthalmologists' views on PACS, with the comparison between 3 platforms, namely electronic patient record (ePR), HEYEX (Heidelberg Engineering, Switzerland), and FORUM (Zeiss, US), following their implementation in an eye hospital for common ophthalmic investigations [visual field, optical coherence tomography (OCT) of retinal nerve fiber layer and macula, and fluorescein/indocyanine green angiography (FA/ICG)]. METHODS: An online survey was distributed among ophthalmologists in a single center. Primary outcome included comparison of PACS with paper-based system. Secondary outcomes included pattern of use and comparison of different PACS platforms. RESULTS: Survey response rate was 28/37 (75.7%). Images were most commonly accessed through ePR (median: 80% of time, interquartile range: 50 to 90%).All systems scored highly in information display items (median scores ≥7.5 out of 10) and in reducing patient identification error in investigation filing and retrieval during consultation compared to paper (score ≥7.0). However, ePR was inferior to paper in "facilitating comparison with previous results" in all investigation types (scores 3.0 to 4.5). ePR scored significantly higher in all system quality items than HEYEX ( P  < 0.001) and FORUM ( P  < 0.022), except login response time ( P  = 0.081). HEYEX scored significantly higher among vitreoretinaluveitis members (VRU) for information quality items for OCT macula and FA/ICG [VRU: 10.0 (8.0 to 10.0), non-VRU: 8.0 (6.75 to 9.25), P  = 0.042]. CONCLUSIONS: Overall feedback for PACS among ophthalmologists was positive, with limitations of inefficiency in use of information, for example, comparison with previous results. Subspecialty played an important role in evaluating PACS.


Subject(s)
Ophthalmologists , Radiology Information Systems , Hospitals , Humans , Surveys and Questionnaires
4.
Diabetes Care ; 44(9): 2078-2088, 2021 09.
Article in English | MEDLINE | ID: mdl-34315698

ABSTRACT

OBJECTIVE: Diabetic macular edema (DME) is the primary cause of vision loss among individuals with diabetes mellitus (DM). We developed, validated, and tested a deep learning (DL) system for classifying DME using images from three common commercially available optical coherence tomography (OCT) devices. RESEARCH DESIGN AND METHODS: We trained and validated two versions of a multitask convolution neural network (CNN) to classify DME (center-involved DME [CI-DME], non-CI-DME, or absence of DME) using three-dimensional (3D) volume scans and 2D B-scans, respectively. For both 3D and 2D CNNs, we used the residual network (ResNet) as the backbone. For the 3D CNN, we used a 3D version of ResNet-34 with the last fully connected layer removed as the feature extraction module. A total of 73,746 OCT images were used for training and primary validation. External testing was performed using 26,981 images across seven independent data sets from Singapore, Hong Kong, the U.S., China, and Australia. RESULTS: In classifying the presence or absence of DME, the DL system achieved area under the receiver operating characteristic curves (AUROCs) of 0.937 (95% CI 0.920-0.954), 0.958 (0.930-0.977), and 0.965 (0.948-0.977) for the primary data set obtained from CIRRUS, SPECTRALIS, and Triton OCTs, respectively, in addition to AUROCs >0.906 for the external data sets. For further classification of the CI-DME and non-CI-DME subgroups, the AUROCs were 0.968 (0.940-0.995), 0.951 (0.898-0.982), and 0.975 (0.947-0.991) for the primary data set and >0.894 for the external data sets. CONCLUSIONS: We demonstrated excellent performance with a DL system for the automated classification of DME, highlighting its potential as a promising second-line screening tool for patients with DM, which may potentially create a more effective triaging mechanism to eye clinics.


Subject(s)
Deep Learning , Diabetes Mellitus , Diabetic Retinopathy , Macular Edema , Diabetic Retinopathy/diagnostic imaging , Humans , Macular Edema/diagnostic imaging , ROC Curve , Tomography, Optical Coherence
5.
Eye (Lond) ; 35(5): 1317-1325, 2021 May.
Article in English | MEDLINE | ID: mdl-32581390

ABSTRACT

OBJECTIVES: To comprehensively assess diabetic retinopathy neurodegeneration (DRN) as quantified by retinal neuronal and axonal layers measured with spectral-domain optical coherence tomography (SD-OCT) in subjects with diabetes mellitus (DM). METHODS: Articles on the topic of examining macular ganglion cell-inner plexiform layer (m-GCIPL), macular retinal nerve fibre layer (m-RNFL), macular ganglion cell complex (m-GCC), and peripapillary RNFL (p-RNFL) measured with SD-OCT in DM subjects without DR (NDR) or with non-proliferative DR (NPDR) were searched in PubMed and Embase up to November 31, 2019. Standardized mean difference (SMD) as effect size were pooled using random-effects model. RESULTS: Thirty-six studies searched from online databases and the CUHK DM cohort were included in the meta-analysis. In the comparison between NDR and control, macular measures including mean m-GCIPL (SMD = -0.26, p = 0.003), m-RNFL (SMD = -0.26, p = 0.046), and m-GCC (SMD = -0.28; p = 0.009) were significantly thinner in the NDR group. In the comparison between NPDR and NDR, only mean p-RNFL was significantly thinner in the NPDR group (SMD = -0.27; p = 0.03), but not other macular measures. CONCLUSIONS: Thinning of retinal neuronal and axonal layers at macula as measured by SD-OCT are presented in eyes with NDR, supporting DRN may be the early pathogenesis in the DM patients without the presence of clinical signs of DR. In the future, these SD-OCT measures may be used as surrogates of DRN to stratify DM patients with a high risk of DR, and may be used as a therapeutic target if neuroprotection treatment for DR is available.


Subject(s)
Macula Lutea , Tomography, Optical Coherence , Humans , Macula Lutea/diagnostic imaging , Nerve Fibers , Retina , Retinal Ganglion Cells
6.
J Neuroophthalmol ; 41(4): e470-e482, 2021 12 01.
Article in English | MEDLINE | ID: mdl-33110004

ABSTRACT

BACKGROUND: The purpose of this study is to quantitatively compare the peripapillary vessel density (PPVD), measured with optical coherence tomography angiography (OCT-A), between acute nonarteritic anterior ischemic optic neuropathy (NAION) and other causes of disc swelling ("others"). METHODS: In this prospective comparative case series, patients with unilateral disc swelling due to acute NAION (n = 7) and "others" (n = 7) underwent OCT-A scanning of the optic nerve head with a swept-source OCT (Triton DRI-OCT), in addition to functional assessment. OCT-A images were analyzed using an automated customized MATLAB program. Comparison was made between total and 6 sectoral PPVD (radial peripapillary capillary [RPC] and choroid layers) of affected and fellow eyes; and between the 2 groups' affected eyes. Five NAION patients had repeated assessments at 1, 3, and 6 months. RESULTS: Acute NAION eyes had a significantly lower total and superonasal PPVD (both layers) compared to fellow eyes. No such difference was observed in "others" group for the RPC layer. NAION eyes also had significantly lower total RPC PPVD than affected eyes in the "others" group. Over 6 months, NAION eyes had persistently lower RPC PPVD compared to fellow eyes but the reduced choroidal PPVD resolved by 1 month. CONCLUSION: The study demonstrated reduced superonasal and total RPC PPVD in acute NAION, which persisted over 6 months. Because there is currently no single diagnostic test for NAION, use of OCT-A images to analyze RPC PPVD may potentially help distinguish acute NAION from other causes of disc swelling by quantitatively demonstrating capillary dropout in the RPC layer.


Subject(s)
Optic Neuropathy, Ischemic , Fluorescein Angiography/methods , Humans , Nerve Fibers , Optic Neuropathy, Ischemic/diagnosis , Pilot Projects , Prospective Studies , Retinal Ganglion Cells , Tomography, Optical Coherence/methods , Visual Acuity , Visual Fields
7.
Eye Vis (Lond) ; 7: 7, 2020.
Article in English | MEDLINE | ID: mdl-32025523

ABSTRACT

BACKGROUND: To test clinically relevant factors associated with quantitative artifact-free deep capillary plexus (DCP) metrics in patients with diabetes mellitus (DM). METHODS: 563 eligible eyes (221 with no diabetic retinopathy [DR], 135 with mild DR, 130 with moderate DR, and 77 with severe DR) from 334 subjects underwent optical coherence tomography-angiography (OCT-A) with a swept-source OCT (Triton DRI-OCT, Topcon, Inc., Tokyo, Japan). Strict criteria were applied to exclude from analysis those DCP images with artifacts and of poor quality, including projection artifacts, motion artifacts, blurriness, signal loss, B-scan segmentation error, or low-quality score. A customized MATLAB program was then used to quantify DCP morphology from the artifact-free DCP images by calculating three metrics: foveal avascular zone (FAZ), vessel density (VD), and fractal dimension (FD). RESULTS: 166 (29.5%) eyes were excluded after quality control, leaving in the analysis 397 eyes (170 with no DR, 101 with mild DR, 90 with moderate DR, 36 with severe DR) from 250 subjects. In the multiple regression models, larger FAZ area was associated with more severe DR (ß = 0.687; p = 0.037), shorter axial length (AL) (ß = - 0.171; p = 0.003), thinner subfoveal choroid thickness (ß = - 0.122; p = 0.031), and lower body mass index (BMI) (ß = - 0.090; p = 0.047). Lower VD was associated with more severe DR (ß = - 0.842; p = 0.001), shorter AL (ß = 0.107; p = 0.039), and poorer visual acuity (VA) (ß = - 0.133; p = 0.021). Lower FD was associated with more severe DR (ß = - 0.891; p < 0.001) and with older age (ß = - 0.142; p = 0.004). CONCLUSIONS: Quantitative artifact-free DCP metrics are associated with VA, DR severity, AL, subfoveal choroidal thickness, age, and BMI in diabetic patients. The effects of ocular and systemic factors should be considered for meaningful interpretations of DCP changes in DM patients.

8.
Ophthalmology ; 126(12): 1675-1684, 2019 12.
Article in English | MEDLINE | ID: mdl-31358386

ABSTRACT

PURPOSE: To prospectively determine the relationship of OCT angiography (OCTA) metrics to diabetic retinopathy (DR) progression and development of diabetic macular edema (DME). DESIGN: Prospective, observational study. PARTICIPANTS: A total of 205 eyes from 129 patients with diabetes mellitus followed up for at least 2 years. METHODS: All participants underwent OCTA with a swept-source OCT device (DRI-OCT Triton, Topcon, Inc, Tokyo, Japan). Individual OCTA images of superficial capillary plexus (SCP) and deep capillary plexus (DCP) were generated by IMAGEnet6 (Basic License 10). After a quality check, automated measurements of foveal avascular zone (FAZ) area, FAZ circularity, vessel density (VD), and fractal dimension (FD) of both SCP and DCP were then obtained. MAIN OUTCOME MEASURES: Progression of DR and development of DME. RESULTS: Over a median follow-up of 27.14 months (interquartile range, 24.16-30.41 months), 28 of the 205 eyes (13.66%) developed DR progression. Of the 194 eyes without DME at baseline, 17 (8.76%) developed DME. Larger FAZ area (hazard ratio [HR], 1.829 per SD increase; 95% confidence interval [CI], 1.332-2.512), lower VD (HR, 1.908 per SD decrease; 95% CI, 1.303-2.793), and lower FD (HR, 4.464 per SD decrease; 95% CI, 1.337-14.903) of DCP were significantly associated with DR progression after adjusting for established risk factors (DR severity, glycated hemoglobin, duration of diabetes, age, and mean arterial blood pressure at baseline). Lower VD of SCP (HR, 1.789 per SD decrease; 95% CI, 1.027-4.512) was associated with DME development. Compared with the model with established risk factors alone, the addition of OCTA metrics improved the predictive discrimination of DR progression (FAZ area of DCP, C-statistics 0.723 vs. 0.677, P < 0.001; VD of DCP, C-statistics 0.727 vs. 0.677, P = 0.001; FD of DCP, C-statistics 0.738 vs. 0.677, P < 0.001) and DME development (VD of SCP, C-statistics 0.904 vs. 0.875, P = 0.036). CONCLUSIONS: The FAZ area, VD, and FD of DCP predict DR progression, whereas VD of SCP predicts DME development. Our findings provide evidence to support that OCTA metrics improve the evaluation of risk of DR progression and DME development beyond traditional risk factors.


Subject(s)
Diabetic Retinopathy/diagnosis , Macular Edema/diagnosis , Retinal Vessels/pathology , Aged , Biometry , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 2/complications , Disease Progression , Female , Fluorescein Angiography , Follow-Up Studies , Humans , Male , Middle Aged , Proportional Hazards Models , Prospective Studies , Retinal Vessels/diagnostic imaging , Risk Factors , Tomography, Optical Coherence , Visual Acuity/physiology
9.
Br J Ophthalmol ; 103(9): 1327-1331, 2019 09.
Article in English | MEDLINE | ID: mdl-30381391

ABSTRACT

AIMS: To evaluate the performance of ultrawide field scanning laser ophthalmoscopy (UWF-SLO) for assessing diabetic retinopathy (DR) and diabetic macular oedema (DME) in a Chinese population, compared with clinical examination. METHODS: This is a retrospective cohort study. A series of 322 eyes from 164 patients with DM were included. Each patient underwent both dilated fundal examination with DR and DME grading by retina specialist and non-mydriatic 200° UWF-SLO (Daytona, Optos, Dunfermline, UK). The severity of DR and DME from UWF-SLO images was further graded by ophthalmologists, according to both international clinical DR and DME disease severity scales and the standard 7-field Early Treatment Diabetic Retinopathy Study (ETDRS) scale. Any DR, DME and vision-threatening DR (VTDR) were treated as endpoints for this study. RESULTS: 23 out of 322 images (7.14%), including all four cases with proliferative DR on clinical examinations, were determined as ungradable. When the international scale was used for grading UWF-SLO images, the sensitivity of any DR, DME and VTDR was 67.7%, 67.4% and 72.6%, respectively; the specificity of any DR, DME and VTDR was 97.8%, 97.3% and 97.8%, respectively. The agreement with clinical grading in picking up any DR, DME and VTDR was substantial, with κ-values of 0.634, 0.694 and 0.707, respectively. The performance of UWF-SLO was shown to be lower when ETDRS scale was used for grading the images. CONCLUSION: The performance of non-mydriatic UWF-SLO is comparable in identifying DR with that of clinical examination in a Chinese cohort. However, whether UWF-SLO can be considered as tool for screening DR is still undetermined.


Subject(s)
Diabetic Retinopathy/diagnostic imaging , Macular Edema/diagnostic imaging , Ophthalmoscopy/methods , Aged , China , Diabetes Mellitus , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity
10.
Neuroophthalmology ; 42(5): 326-333, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30258481

ABSTRACT

The 33rd Asia-Pacific Academy of Ophthalmology (APAO) Congress was held on Feb 8-11, 2018 in Hong Kong. This report summarized the highlights of the neuro-ophthalmology program of the Congress, including the scientific symposia (invited and submitted) and the social activities.

11.
Br J Ophthalmol ; 2018 Jun 04.
Article in English | MEDLINE | ID: mdl-29866787

ABSTRACT

AIM: To examine the correlation of best-corrected visual acuity (BCVA) with intercapillary area (ICA) measured from optical coherence tomography angiography (OCT-A) in patients with diabetes, and to compare the strength of associations between BCVA with ICA and other OCT-A metrics. METHODS: A cross-sectional study involved 447 eyes from 299 patients with diabetes. All participants underwent OCT-A with a swept-source OCT (Triton DRI-OCT, Topcon, Tokyo, Japan). An automated customised MATLAB programme was used to quantify ICA (the mean of the 10 largest areas including foveal avascular zone (FAZ) area (ICA10_FAZ) and excluding FAZ area (ICA10_excFAZ)) and other OCT-A metrics (FAZ area, FAZ circularity and vessel density) from the macular OCT-A images. BCVA was measured using Snellen chart for the patients and then converted to logarithm of the minimum angle of resolution (logMAR) VA. We further defined 'good VA' as Snellen >0.7 and 'poor VA' as Snellen ≤0.7 as a binary VA outcome for logistic regression analysis. RESULTS: In univariate regression analysis, increased ICA10_FAZ and ICA10_excFAZ were significantly correlated with logMAR (p values <0.05). In multivariate regression analysis, only the association between ICA10_FAZ and logMAR persisted (ß=0.103, p=0.024). In multivariable logistic regression analysis, increased ICA10_FAZ (OR=1.300, 95% CI 1.076 to 1.679, p=0.044) and FAZ circularity (OR=1.285, 95% CI 1.031 to 1.603, p=0.026) showed significant associations with poor VA. CONCLUSIONS: Increased ICA measured from OCT-A, describing enlargement of capillary rarefaction or closure at macular area, is independently associated with BCVA, suggesting that ICA is a potential marker to quantify retinal microvascular abnormalities relating to vision among individuals with diabetes.

12.
Clin Ophthalmol ; 12: 885-893, 2018.
Article in English | MEDLINE | ID: mdl-29785084

ABSTRACT

OBJECTIVE: To identify residents' perceived barriers to learning phacoemulsification surgical procedures and to evaluate whether virtual reality simulation training changed these perceptions. DESIGN: The ophthalmology residents undertook a simulation phacoemulsification course and proficiency assessment on the Eyesi system using the previously validated training modules of intracapsular navigation, anti-tremor, capsulorrhexis, and cracking/chopping. A cross-sectional, multicenter survey on the perceived difficulties in performing phacoemulsification tasks on patients, based on the validated International Council of Ophthalmology's Ophthalmology Surgical Competency Assessment Rubric (ICO-OSCAR), using a 5-point Likert scale (1 = least and 5 = most difficulty), was conducted among residents with or without prior simulation training. Mann-Whitney U tests were carried out to compare the mean scores, and multivariate regression analyses were performed to evaluate the association of lower scores with the following potential predictors: 1) higher level trainee, 2) can complete phacoemulsification most of the time (>90%) without supervisor's intervention, and 3) prior simulation training. SETTING: The study was conducted in ophthalmology residency training programs in five regional hospitals in Hong Kong. RESULTS: Of the 22 residents, 19 responded (86.3%), of which 13 (68.4%) had completed simulation training. Nucleus cracking/chopping was ranked highest in difficulty by all respondents followed by capsulorrhexis completion and nucleus rotation/manipulation. Respondents with prior simulation training had significantly lower difficulty scores on these three tasks (nucleus cracking/chopping 3.85 vs 4.75, P = 0.03; capsulorrhexis completion 3.31 vs 4.40, P = 0.02; and nucleus rotation/manipulation 3.00 vs 4.75, P = 0.01). In multivariate analyses, simulation training was significantly associated with lower difficulty scores on these three tasks. CONCLUSION: Residents who had completed Eyesi simulation training had higher confidence in performing the most difficult tasks perceived during phacoemulsification.

13.
Sci Rep ; 8(1): 7314, 2018 May 04.
Article in English | MEDLINE | ID: mdl-29728691

ABSTRACT

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

15.
Sci Rep ; 7(1): 2575, 2017 05 31.
Article in English | MEDLINE | ID: mdl-28566760

ABSTRACT

Early microvascular damage in diabetes (e.g. capillary nonperfusion and ischemia) can now be assessed and quantified with optical coherence tomography-angiography (OCT-A). The morphology of vascular tissue is indeed affected by different factors; however, there is a paucity of data examining whether OCT-A metrics are influenced by ocular, systemic and demographic variables in subjects with diabetes. We conducted an observational cross-sectional study and included 434 eyes from 286 patients with diabetes. Foveal avascular zone (FAZ) area, FAZ circularity, total and parafoveal vessel density (VD), fractal dimension (FD), and vessel diameter index (VDI) from the superficial capillary plexus OCT-angiogram were measured by a customized automated image analysis program. We found that diabetic retinopathy (DR) severity was associated with increased FAZ area, decreased FAZ circularity, lower VD, lower FD, and increased VDI. Enlarged FAZ area was correlated with shorter axial length and thinner central subfield macular thickness. Decreased FAZ circularity was correlated with a reduction in visual function. Decreased VD was correlated with thinner macular ganglion-cell inner plexiform layer. Increased VDI was correlated with higher fasting glucose level. We concluded that the effects of ocular and systemic factors in diabetics should be taken into consideration when assessing microvascular alterations via OCT-A.


Subject(s)
Computed Tomography Angiography/methods , Diabetes Complications/diagnostic imaging , Diabetic Retinopathy/diagnostic imaging , Retinal Vessels/diagnostic imaging , Adult , Aged , Cross-Sectional Studies , Diabetes Complications/physiopathology , Diabetic Retinopathy/etiology , Diabetic Retinopathy/physiopathology , Female , Fluorescein Angiography/methods , Fovea Centralis/diagnostic imaging , Fovea Centralis/physiopathology , Humans , Macula Lutea/diagnostic imaging , Macula Lutea/physiopathology , Male , Middle Aged , Retinal Vessels/physiopathology , Tomography, Optical Coherence/methods , Visual Acuity/physiology
16.
Int Ophthalmol ; 35(5): 679-84, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25183461

ABSTRACT

The aim of the study was to evaluate the indications and outcomes of intraocular lens (IOL) explantation in Chinese patients. The medical records of all Chinese patients who underwent IOL explantation in Hong Kong Eye Hospital, from January 2008 to March 2013, were reviewed. A total of 98 IOLs were explanted over the study period. The main reasons for lens removal included lens malposition (71.4%), isolated uveitis-glaucoma-hyphema (UGH) syndrome (9.1%), refractive surprise (6.1%), and pseudophakic bullous keratopathy (4.1%). "In-the-bag" IOL malposition was associated with intraocular complications during cataract extraction (28.9%) and high myopia (22.2%). Sulcus implantation of a single-piece acrylic (SPA) IOL resulted in UGH syndrome in all cases, while sulcus-fixated 3-piece lenses had such complication in only 7.1% of cases. Importantly, the problem persisted despite the removal of the SPA IOL from the ciliary sulcus. Majority of the patients had resolution of the original problems after lens removal or exchange and had the same or improved visual acuity after surgery. Lens malposition was the major indication of intraocular lens explantation in our case series. Resolution of symptoms and visual acuity can be achieved with IOL explantation. Implantation of SPA in ciliary sulcus is not recommended.


Subject(s)
Cataract Extraction/adverse effects , Device Removal , Lenses, Intraocular , Postoperative Complications/surgery , Aged , Female , Hong Kong , Humans , Male , Middle Aged , Prosthesis Failure , Retrospective Studies , Visual Acuity/physiology
17.
Ann Thorac Surg ; 95(4): e95-6, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23522241

ABSTRACT

Although aberrant right subclavian artery is the commonest aortic arch anomaly, it is a rare entity in clinical practice. While mostly asymptomatic, the rupture of an aneurysm of an aberrant right subclavian artery or Kommerell's diverticulum can be life threatening. A conventional open surgical approach involving sternotomy and resection of the abnormal vessels under circulatory support carries significant morbidity and mortality. We report a case of a ruptured diverticulum of Kommerell that was successfully treated with a hybrid debranching surgery, Amplatzer device embolization of the subclavian vessels, and thoracic aortic endovascular stenting.


Subject(s)
Aneurysm, Ruptured/therapy , Embolization, Therapeutic/methods , Endovascular Procedures/methods , Stents , Subclavian Artery/abnormalities , Adult , Aneurysm, Ruptured/diagnostic imaging , Angiography , Humans , Male , Subclavian Artery/diagnostic imaging , Subclavian Artery/surgery , Tomography, X-Ray Computed
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