Education & Certifications
Bachelor of Science, Rice University, Biochemistry (2017)
Bachelor of Arts, Rice University, Medieval, Early Modern Studies (2017)
Previous deep learning studies on optical coherence tomography (OCT) mainly focused on diabetic retinopathy and age-related macular degeneration. We proposed a deep learning model that can identify epiretinal membrane (ERM) in OCT with ophthalmologist-level performance.Cross-sectional study.A total of 3,618 central fovea cross section OCT images from 1,475 eyes of 964 patients.We retrospectively collected 7,652 OCT images from 1,197 patients. From these images, 2,171 were normal and 1,447 were ERM OCT. A total of 3,141 OCT images was used as training dataset and 477 images as testing dataset. DL algorithm was used to train the interpretation model. Diagnostic results by four board-certified non-retinal specialized ophthalmologists on the testing dataset were compared with those generated by the DL model.We calculated for the derived DL model the following characteristics: sensitivity, specificity, F1 score and area under curve (AUC) of the receiver operating characteristic (ROC) curve. These were calculated according to the gold standard results which were parallel diagnoses of the retinal specialist. Performance of the DL model was finally compared with that of non-retinal specialized ophthalmologists.Regarding the diagnosis of ERM in OCT images, the trained DL model had the following characteristics in performance: sensitivity: 98.7%, specificity: 98.0%, and F1 score: 0.945. The accuracy on the training dataset was 99.7% (95% CI: 99.4 - 99.9%), and for the testing dataset, diagnostic accuracy was 98.1% (95% CI: 96.5 - 99.1%). AUC of the ROC curve was 0.999. The DL model slightly outperformed the average non-retinal specialized ophthalmologists.An ophthalmologist-level DL model was built here to accurately identify ERM in OCT images. The performance of the model was slightly better than the average non-retinal specialized ophthalmologists. The derived model may play a role to assist clinicians to promote the efficiency and safety of healthcare in the future.
View details for DOI 10.1038/s41598-020-65405-2
View details for PubMedID 32439844
This story is based on a series of encounters between the author-a medical student-and a hospitalized patient with terminal cancer. Over multiple conversations, the narrator becomes closely acquainted with the patient's life and outlook, and helps her navigate an important decision regarding the course of her treatment. In the process, the narrator is given the opportunity to examine the limits of medicine and what matters to patients at the end of life.
View details for DOI 10.7812/TPP/19.033
View details for PubMedID 31852043
View details for PubMedCentralID PMC6907916
A cyclodialysis cleft often leads to direct communication between the anterior chamber and the suprachoroidal space. It is a rare condition that is encountered with blunt trauma, and less commonly, after surgery. Hypotony is the major sequelae that may lead to hypotonous maculopathy, optic disc edema, corneal folds, and astigmatism. These may cumulatively lead to visual loss. We describe how endoscopy in a cyclodialysis repair allowed us to accurately locate the cleft and guided its appropriate management avoiding unnecessary cryopexy.A 41-year-old male experienced a traumatic cyclodialysis cleft, which resulted in persistent hypotony. Pars plana vitrectomy was performed to treat vitreous hemorrhage. Scleral indentation was attempted to visualize the cyclodialysis cleft. However, the depression distorted the visualization. Intraocular endoscopy was therefore used to evaluate the cleft. Guided by this assessment, only intraocular gas tamponade was used to reposition the ciliary body. The patient's intraocular pressure was restored to 13 mmHg 3 days after the operation, and OCT confirmed cleft closure 1 month after the operation.Endoscopy-assisted repair of cyclodialysis is an approach that enhances visualization and can guard against common causes of persistent cleft and hypotony, as well as reveal the causes of recurrent failure. Hence, it can eliminate unnecessary cryopexy that might worsen the hypotonous state. In our case, intraocular endoscopy was effective for the evaluation of a cyclodialysis cleft and the subsequent selection of an appropriate management technique, gas tamponade, that was more conservative than other approaches initially considered.
View details for DOI 10.1186/s12886-020-01375-3
View details for PubMedID 32293350
To evaluate the efficacy of microincision vitrectomy surgery (MIVS) for the treatment of post-cataract surgery endophthalmitis, and to report the factors which influence the outcome.This retrospective case series included eyes with post-cataract surgery endophthalmitis that had received MIVS between June 2014 and May 2017. The anatomical and functional results were analyzed.24 eyes of 24 patients were included with mean age 72.0 ± 8.6 years old. Best-corrected visual acuity (BCVA) improved in 70.8% of patients with a significant mean logMAR BCVA change of -0.6 ± 0.9. Positive culture rate was 25%. In all study eyes, inflammation became silent after MIVS. In univariate analysis, patients with improved BCVA have shorter duration between cataract surgery and MIVS and less likely to have positive culture results. Using degree of BCVA improvement as a continuous variable, it showed that duration between cataract surgery and MIVS had significantly negative correlation with BCVA improvement. Patients with positive culture results had significantly lower BCVA improvement. Multiple regression models also confirmed the most important outcome-influencing factors.MIVS is an efficient management for post-cataract surgery endophthalmitis. BCVA is significantly improved after MIVS. No matter in univariate or multivariate analysis, positive culture results and longer duration between cataract surgery and MIVS have significant negative effects on the outcome of post-cataract surgery endophthalmitis. Multicenter collaboration should be conducted in order to formulate better management protocols of this vision-threatening complication of cataract surgery.
View details for DOI 10.1016/j.jfma.2019.06.010
View details for PubMedID 31296362
In this narrative account, the author, a medical student, describes his encounters with several inpatients at a community hospital. He becomes acquainted with a patient's son, who, initially withdrawn, over the course of his mother's hospitalizations transforms into a compassionate volunteer. This change is made especially evident when the author meets another patient who recognizes the volunteer and reveals his very different past.
View details for DOI 10.3122/jabfm.2020.03.190291
View details for PubMedID 32430384
In this narrative essay, the author, a medical student, describes a patient who was nearing the end of her life and who feared passing away before she could witness her daughter's wedding. This story describes the lengths to which the medical team went to in order to address this concern, illustrating a particularly humanistic instance of what end-of-life care can mean.
View details for DOI 10.1016/j.pec.2019.11.006
View details for PubMedID 31744703
This short story is based on and told from the perspective of a patient the author encountered as a medical student. The story explores the thoughts of an elderly patient, who is hospitalized because of multiple organ failure, as she contemplates the voluntary refusal of food, fluid, and antibiotics. The patient weighs these options in light of her beliefs and experiences, and in the face of seemingly futile medicalization.
View details for DOI 10.7812/TPP/18.283
View details for PubMedID 31634109
To evaluate the efficacy of micro-incision vitrectomy surgery (MIVS) using Lumera and Resight non-contact sutureless wide-angle viewing systems (WAVS) for primary rhegmatogenous retinal detachment (RRD), and to analyze the anatomical and visual outcomes.The retrospective, non-comparative, interventional case series reported here was conducted from June 2014 through November 2016. Enrolled patients presented with primary RRD and received MIVS with/without cryopexy by one surgeon using the Lumera and Resight non-contact sutureless WAVS. All patients were followed-up for a minimum of 12 months. Variables collected included patient demographics, best-corrected visual acuity, and macular status. The number and position of retinal break(s), and the use of cryopexy, were also recorded. Outcome measures included operative time, single-operation anatomical success rate, final anatomical success rate, recurrent rate, postoperative best-corrected visual acuity, and surgical complications. The end points were operative time, anatomical outcome, and functional outcome.In total, 110 eyes from 110 patients (68 men and 42 women) were treated. Of these, 103 (93%) eyes were reattached after primary vitrectomy. One hundred ten eyes (100%) reached final anatomical success. The mean operative time was 50.55 min. Multivariate analyses were performed with best model selection principle based on general linear model by Akaike Information Criteria for detecting possible factors related to operation time, and with multivariate logistic regression analysis for revealing probable clinical parameters which might influence the anatomical outcome after first operation and final visual outcome. Intraoperative cryopexy and multiple breaks increased operative time significantly. More favorable BCVA was significantly correlated with shorter operation time and the preoperative macula-on status. Multivariate logistic regression on the group of patients who have received the cataract surgery revealed that the pre-operative BCVA is a significant factor which can predict the visual outcome after MIVS.The outcome of primary RRD repaired by MIVS using the Lumera and Resight sutureless WAVS was not inferior to any other published method. This instrument combination resulted in a relatively rapid and comfortable procedure without serious postoperative complications. Cryopexy and multiple breaks affected operative time significantly. Shorter operative times and preoperative macula-on status are associated with better final visual outcomes.
View details for DOI 10.1186/s12886-019-1238-3
View details for PubMedID 31744475
PURPOSE: The aim of this study is to evaluate the clinical use of ultra-widefield angiography (UWFA) in uveitis.MATERIALS AND METHODS: We showed the UWFA and traditional 55° fluorescein angiography (FA) of four cases with Eales' disease, idiopathic retinal vasculitis, aneurysms, and neuroretinitis syndrome, Behcet's disease, and idiopathic panuveitis in a tertiary medical center. Comparison of UWFA with traditional 55°FA in the diagnosis and management of uveitis and review of the literature is also presented.RESULTS: Ultra-widefield FA revealed far-peripheral vascular imaging. This information would not have been easily obtained from traditional FA. With more information of the peripheral retina, it may facilitate appropriate diagnosis and monitoring, and the management may be revised.CONCLUSION: University of Western Australia played an important role to confirm the diagnosis of uveitis and to determine the corresponding treatment.
View details for PubMedID 30294529
Extracellular vesicles (EVs) secreted by mesenchymal stromal cells (MSCs) have been proposed to be a key mechanistic link in the therapeutic efficacy of cells in response to cellular injuries through paracrine effects. We hypothesize that inflammatory stimulation of MSCs results in the release of EVs that have greater anti-inflammatory effects. The present study evaluates the immunomodulatory abilities of EVs derived from inflammation-stimulated and naive MSCs (MSCEv(+) and MSCEv, respectively) isolated using a current Good Manufacturing Practice (cGMP)-compliant tangential flow filtration (TFF) system. Detailed characterization of both EVs revealed differences in protein composition, cytokine profiles, and RNA content, despite similarities in size and expression of common surface markers. MSCEv(+) further attenuated release of pro-inflammatory cytokines in vitro when compared to MSCEv, with a distinctly different pattern of EV-uptake by activated primary leukocyte subpopulations. The efficacy of EVs was partially attributed to COX2/PGE2 expression. The present study demonstrates that inflammatory stimulation of MSCs renders release of EVs that have enhanced anti-inflammatory properties partially due to COX2/PGE2 pathway alteration. This article is protected by copyright. All rights reserved.
View details for PubMedID 29076623
Although it is well known that nitrofen induces congenital diaphragmatic hernia (CDH), including CDH-associated lung hypoplasia and pulmonary hypertension (PH) in rodents, the mechanism of pathogenesis remains largely unclear. It has been reported that pulmonary artery (PA) endothelial cell (EC) dysfunction contributes to the development of PH in CDH. Thus, we hypothesized that there is significant alteration of endothelial dysfunction-associated proteins in nitrofen-induced CDH PAs. Pregnant SD rats received either nitrofen or olive oil on gestational day 9.5. The newborn rats were sacrificed and divided into a CDH (n = 81) and a control (n = 23) group. After PA isolation, the expression of PA endothelial dysfunction-associated proteins was assessed on Western blot and immunostaining. We demonstrate that the expression of C-reactive protein and endothelin-1 and its receptors, ETA and ETB, were significantly increased in the CDH PAs. Levels of phosphorylated myosin light chain were significantly elevated, but those of phosphorylated endothelial nitric oxide synthase, caveolin-1, and mechanistic target of rapamycin were significantly decreased in the CDH PAs. In this work, we elucidate alterations in the expression of endothelial dysfunction-associated proteins specific to nitrofen-induced CDH rodent PAs, thereby advancing our understanding of the critical role of endothelial dysfunction-associated pathways in the pathogenesis of nitrofen-induced CDH.
View details for PubMedID 29216632
Electronegative low-density lipoprotein (LDL) found in human plasma is highly atherogenic, and its level is elevated in individuals with increased cardiovascular risk. In this review, we summarize the available data regarding the elevation of the levels of electronegative LDL in the plasma of patients with various diseases. In addition, we discuss the harmful effects and underlying mechanisms of electronegative LDL in various cell types. We also highlight the known biochemical properties of electronegative LDL that may contribute to its atherogenic functions, including its lipid and protein composition, enzymatic activities, and structural features. Given the increasing recognition of electronegative LDL as a potential biomarker and therapeutic target for the prevention of cardiovascular disease, key future goals include the development of a standard method for the detection of electronegative LDL that can be used in a large-scale population survey and the identification and testing of strategies for eliminating electronegative LDL from the blood.
View details for DOI 10.1007/s11883-014-0428-y
View details for Web of Science ID 000340523400002
View details for PubMedID 24890631
Increased levels of the most electronegative type of LDL, L5, have been observed in the plasma of patients with metabolic syndrome (MetS) and ST-segment elevation myocardial infarction and can induce endothelial dysfunction. Because men have a higher predisposition to developing coronary artery disease than do premenopausal women, we hypothesized that LDL electronegativity is increased in men and promotes endothelial damage.L5 levels were compared between middle-aged men and age-matched, premenopausal women with or without MetS. We further studied the effects of gender-influenced LDL electronegativity on aortic cellular senescence and DNA damage in leptin receptor-deficient (db/db) mice by using senescence-associated-β-galactosidase and γH2AX staining, respectively. We also studied the protective effects of 17β-estradiol and genistein against electronegative LDL-induced senescence in cultured bovine aortic endothelial cells (BAECs).L5 levels were higher in MetS patients than in healthy subjects (P < 0.001), particularly in men (P = 0.001). LDL isolated from male db/db mice was more electronegative than that from male or female wild-type mice. In addition, LDL from male db/db mice contained abundantly more apolipoprotein CIII and induced more BAEC senescence than did female db/db or wild-type LDL. In the aortas of db/db mice but not wild-type mice, we observed cellular senescence and DNA damage, and the effect was more significant in male than in female db/db mice. Pretreatment with 17β-estradiol or genistein inhibited BAEC senescence induced by male or female db/db LDL and downregulated the expression of lectin-like oxidized LDL receptor-1 and tumor necrosis factor-alpha protein.The gender dichotomy of LDL-induced cardiovascular damage may underlie the increased propensity to coronary artery disease in men.
View details for DOI 10.1186/1475-2840-13-64
View details for Web of Science ID 000334807000001
View details for PubMedID 24666525
View details for PubMedCentralID PMC3974745