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Featured researches published by Tun-Lu Chen.


Ophthalmology | 2012

Visual Acuity, Optical Components, and Macular Abnormalities in Patients with a History of Retinopathy of Prematurity

Wei-Chi Wu; Rey-In Lin; Chia-Pang Shih; Nan-Kai Wang; Yen-Po Chen; An-Ning Chao; Kuan-Jen Chen; Tun-Lu Chen; Yih-Shiou Hwang; Chi-Chun Lai; Chung-Ying Huang; Shawn H. Tsai

PURPOSE To examine the optical components and spectral-domain optical coherence tomography (OCT) findings in children with a history of retinopathy of prematurity (ROP) and to identify any associations between the OCT findings and the visual acuities of the patients. DESIGN Prospective, case-controlled study. PARTICIPANTS AND CONTROLS Children who were between 6 and 14 years of age were divided into the following 4 groups: Patients with a history of threshold ROP who had been treated using laser therapy or cryotherapy (group 1), patients with regressed ROP who had not received any treatment (group 2), patients who were born prematurely but who had no history of ROP (group 3), and normal full-term children (group 4). The posterior poles of the eyes of all of the patients seemed to be normal. METHODS Visual acuities, optical components, and macular thicknesses were measured in 4 groups of patients, and comparisons between the groups were made. Macular thicknesses were measured using OCT. MAIN OUTCOME MEASURES Visual acuity (VA), optical components, and OCT findings. RESULTS We enrolled 133 patients in the study. Patients in group 1 had significantly thicker foveas than the other patients, as demonstrated by OCT, and this finding was negatively correlated with gestational age. The incidence of abnormal foveal contours among patients in group 1 was significantly higher than among the rest of the patients. Retention of the inner retinal layers was noted in group 1 patients; however, the structure of the outer retina remained intact. Greater degrees of myopic shift and astigmatism, steeper corneal curvatures, shallower anterior chamber depths, and thicker lenses were noted in previously treated ROP patients. These findings corresponded with poor VA and high refractive errors in group 1 patients. CONCLUSIONS Patients with a history of threshold ROP are more likely to show abnormal foveal development and have a poorer visual prognosis than other patient groups despite a fundus with no macular dragging, disc dragging, or retinal detachment. A steeper corneal curvature, shallower anterior chamber, and greater lens thickness are the main changes in the optical components in these patients.


Retina-the Journal of Retinal and Vitreous Diseases | 2006

Treatment of retinal detachment resulting from posterior staphyloma-associated macular hole in highly myopic eyes.

Yen-Po Chen; Tun-Lu Chen; Ken-Ren Yang; Wen-Hao Lee; Ya-Hui Kuo; An-Ning Chao; Wei-Chi Wu; Kuan-Jen Chen; Chi-Chun Lai

Purpose: To evaluate the surgical outcome of retinal detachment resulting from a posterior staphyloma–associated macular hole in highly myopic eyes. Methods: Fifty-seven consecutive highly myopic eyes with retinal detachment resulting from a posterior staphyloma–associated macular hole diagnosed between January 1993 and June 2003 were retrospectively studied. Anatomical reattachment of the retina and best-corrected visual acuity were measured. Results: Six different operative methods were used to treat this condition with diverse retinal reattachment rates: long-acting gas tamponade only (12.5%); pars plana vitrectomy (PPV) with long-acting gas tamponade (42.8%); PPV with epiretinal membrane (ERM) peeling and long-acting gas tamponade (50.0%); encircling scleral buckling combined with PPV and long-acting gas tamponade (57.1%); encircling scleral buckling combined with PPV, ERM peeling, and long-acting gas tamponade (40.0%); and encircling scleral buckling combined with PPV and silicone oil tamponade (75.0%). Overall, successful retinal reattachment was achieved in 25 (43.9%) of 57 eyes after the first surgery. However, the ultimate success rate of retinal reattachment was 77.2% (44 of 57 eyes) after subsequent surgery. The mean preoperative visual acuity ± SEM (in logarithm of the minimal angle of resolution units) was 2.08 ± 0.55, and the mean postoperative visual acuity ± SEM was significantly increased to 1.87 ± 0.54 at the last follow-up (P = 0.038). The major cause of recurrent retinal detachment in the long-acting gas tamponade group was nonclosure of the macular hole. For vitrectomized eyes, the major cause was reopening of the macular hole, even with ERM formation and proliferative vitreoretinopathy. There was no obvious correlation between the extent of the detachment or lens status and the reattachment rate. Conclusions: The major causes of recurrent retinal detachment in the long-acting gas tamponade and vitrectomized groups were nonclosure of the macular hole and reopening of the macular hole, respectively. Furthermore, a lesser extent of retinal detachment was not associated with a higher anatomical success rate. More aggressive treatment such as silicone oil tamponade may need to be performed to overcome reduced natural adhesion due to posterior staphyloma with marked chorioretinal atrophy. Failure to initiate aggressive treatment can result in an unsatisfactory outcome and repeated surgery.


JAMA Ophthalmology | 2015

Serum Levels of Vascular Endothelial Growth Factor and Related Factors After Intravitreous Bevacizumab Injection for Retinopathy of Prematurity

Wei-Chi Wu; Reyin Lien; Pei-Ju Liao; Nan-Kai Wang; Yen-Po Chen; An-Ning Chao; Kuan-Jen Chen; Tun-Lu Chen; Yih-Shiou Hwang; Chi-Chun Lai

IMPORTANCE Intravitreous injections of bevacizumab (IVB) have been found to be effective for the treatment of retinopathy of prematurity (ROP). However, serum levels of vascular endothelial growth factor (VEGF) have been found to be suppressed for 2 weeks after IVB in patients with ROP. Changes in serum VEGF levels after IVB in patients with ROP may be important because VEGF also plays a role in the neurodevelopment of newborns. OBJECTIVE To investigate the correlation of levels of VEGF and related growth factors with bevacizumab levels in the systemic circulation after IVB in patients with type 1 ROP. DESIGN, SETTING, AND PARTICIPANTS We studied a prospective case series at an institutional referral center from December 1, 2011, through February 28, 2013. We enrolled patients with type 1 ROP who received IVB. We collected blood samples before and for as long as 8 weeks after IVB. The samples were tested for serum levels of bevacizumab and growth factors, including VEGF, VEGF receptor 1 (VEGFR1), VEGFR2, Tie2, erythropoietin, transforming growth factor β1, insulinlike growth factor type 1, angiopoietin 1, angiopoietin 2, angiopoietinlike 3, and angiopoietin 4. The serum concentrations of these factors were measured using enzyme-linked immunosorbent assays. MAIN OUTCOMES AND MEASURES Serum levels of VEGF, bevacizumab, and the other growth factors before and for as long as 8 weeks after IVB. RESULTS We enrolled 8 patients with type 1 ROP. Bevacizumab levels were elevated 1 day after IVB in the 3 patients for whom measurements were available (mean [SD], 1425 [1010 (95% CI, 0-3934)] ng/mL; P = .13) and remained detectable in the serum as long as 8 weeks after IVB (285 ng/mL for the 1 patient with a measurement available). Serum VEGF levels were suppressed for the same period (mean [SD] level at 1 day after IVB, 379 [226 (95% CI, 190-568)] pg/mL for the 3 patients with measurements available; at 8 weeks, 216 pg/mL for the 1 patient with a measurement available). We found a negative correlation between the serum levels of bevacizumab and VEGF in the patients with ROP who received IVB (r = -0.43 [95% CI, -0.67 to -0.10]; P = .01). No changes were identified in the serum levels of any of the other factors after IVB. Bevacizumab may interfere with the actual level of VEGF in the serum, and the total VEGF level in the serum cannot be determined when bevacizumab is present. Wide CIs were noted in the measurement of these factors, probably owing to the small number of patients enrolled in this study. CONCLUSIONS AND RELEVANCE Serum VEGF levels were suppressed for 2 months after IVB in patients with type 1 ROP owing to the leakage of bevacizumab into the systemic circulation.


American Journal of Ophthalmology | 2012

Classification of Early Dry-Type Myopic Maculopathy with Macular Choroidal Thickness

Nan-Kai Wang; Chi-Chun Lai; Hsueh-Yen Chu; Yen-Po Chen; Kuan-Jen Chen; Wei-Chi Wu; Lung-Kun Yeh; Lan-Hsin Chuang; Tun-Lu Chen

PURPOSE To compare the macular choroidal thickness in 2 types of early dry-type myopic maculopathy. DESIGN Prospective, observational, comparative study. METHODS Patients with a refractive error of less than -8 diopters were included and were classified into 2 groups. Group 1 consisted of 24 eyes with a tessellated fundus, and group 2 consisted of 33 eyes with diffuse chorioretinal atrophy, but not to the extent of patchy chorioretinal atrophy. These 2 groups were compared with regard to their clinical characteristics, refractive error, axial length, macular choroidal thickness, and best-corrected visual acuity (BCVA). Linear regression was used to evaluate the explanatory variables in terms of macular choroidal thickness and BCVA. RESULTS Patients in group 1 were significantly younger and had better BCVA, less myopia, shorter axial length, and less staphyloma than those in group 2. Refractive error, axial length, and BCVA correlated significantly with macular choroidal thickness in group 2. However, no such significant correlations were observed in group 1. Multiple linear regression analysis showed that age and macular choroidal thickness were the variables that associated most strongly with BCVA, whereas neither refractive error nor axial length was a significant predictor of BCVA. In group 2, eyes with lacquer cracks showed worse BCVA and thinner macular choroidal thickness than eyes without lacquer cracks. CONCLUSIONS Macular choroidal thickness is an important factor in myopic maculopathy and can be a better indicator of its severity. These findings suggest that BCVA reduction in eyes with dry-type myopic maculopathy can be related to a thinner macular choroidal thickness and to the development of lacquer cracks.


Investigative Ophthalmology & Visual Science | 2010

Long-Term Tolerability and Serum Concentration of Bevacizumab (Avastin) when Injected in Newborn Rabbit Eyes

Wei-Chi Wu; Chi-Chun Lai; Kuan-Jen Chen; Tun-Lu Chen; Nan-Kai Wang; Yih-Shiou Hwang; Ling Yeung; Lien-Min Li

PURPOSE. To test the long-term effects and systemic exposure level after single or multiple bevacizumab (Avastin) intravitreal injections in newborn rabbit eyes. METHODS. Four groups of newborn New Zealand rabbits received a single intravitreal bevacizumab injection at a concentration of 1.25 mg/0.05 mL at the ages of 2 (group 1), 4 (group 2), 6 (group 3), and 12 (group 5) weeks. The other group of rabbits (group 4) received three consecutive injections of bevacizumab at a concentration of 1.25 mg/0.05 mL at weeks 2, 6, and 10. Eight days after injection, the serum concentration of bevacizumab was determined in groups 1, 2, 3, and 5. Morphologic and functional changes were evaluated 12 months after bevacizumab injection. RESULTS. Twelve months after either single or multiple intravitreal injections of bevacizumab, newborn rabbit eyes showed no significant differences compared with control eyes on examination with funduscopy, histopathology, or electroretinogram. The serum concentrations when the injections were performed at the ages of 2 (19.4 +/- 8.1 microg/mL) and 4 (10.2 +/- 2.3 microg/mL) weeks were significantly higher than the serum level detected when the injection was performed at 12 weeks of age (2.8 +/- 1.2 microg/mL, P = 0.02 and P = 0.024, respectively). CONCLUSIONS. After 1 year, single and three consecutive intravitreal injections of 1.25 mg bevacizumab in newborn rabbit eyes are well tolerated. Systemic exposure is higher when the injection is performed at an early age.


JAMA Ophthalmology | 2013

Choroidal Thickness in Patients With a History of Retinopathy of Prematurity

Wei-Chi Wu; Chia-Pang Shih; Nan-Kai Wang; Reyin Lien; Yen-Po Chen; An-Ning Chao; Kuan-Jen Chen; Tun-Lu Chen; Yih-Shiou Hwang; Chi-Chun Lai; Chung-Ying Huang; Shawn H. Tsai

IMPORTANCE The cause of reduced vision in patients with a history of retinopathy of prematurity (ROP) is not yet fully understood. The role of the choroid in ROP remains unknown and existing studies of choroidal thickness in patients with a history of ROP are limited. It might be helpful to understand the association of the choroid with ROP by measuring the choroidal thickness in patients with a history of ROP and correlating these findings with the visual outcome of these patients. OBJECTIVE To examine choroidal thickness by spectral-domain optical coherence tomography in children with a history of ROP and assess the impact of choroidal thickness on visual acuity. DESIGN A prospective cross-sectional analysis from August 2011 to September 2012. SETTING Institutional referral centers. PARTICIPANTS Children aged 6 to 14 years with a history of ROP were classified into the following 2 groups: patients with a history of threshold ROP and treatment with laser or cryotherapy (treated group) and those with regressed ROP who had not received any treatment (nontreated group). All of the patients had a normal-appearing posterior pole. INTERVENTION Examinations of visual acuity, refractive errors, and optical components and measurement of choroidal thickness. MAIN OUTCOMES AND MEASURES Best-corrected visual acuity, optical components, and optical coherence tomography findings. RESULTS In total, 49 patients were enrolled in the study. Patients in the treated group had a significantly thinner choroidal thickness than the patients in the nontreated group after adjusting for age, axial length, and spherical power. Choroidal thickness was found to be positively associated with spherical power and spherical equivalent and negatively associated with axial length and vitreous depth. In addition, a thin choroidal thickness was associated with a worse best-corrected visual acuity. CONCLUSIONS AND RELEVANCE Choroidal thickness is thinner in patients with threshold ROP compared with the patients with spontaneously regressed ROP. A thinner choroid is associated with worse vision in these patients. This study might imply the association of choroid circulation with ROP.


Graefes Archive for Clinical and Experimental Ophthalmology | 2011

The validity of clinical feature profiles for cytomegaloviral anterior segment infection

Yih-Shiou Hwang; Chia-Rui Shen; Shirley H. L. Chang; Chi-Chun Lai; Chao-Lin Liu; Kuan-Jen Chen; Ken-Kuo Lin; Tun-Lu Chen; Ching-Hsi Hsiao

BackgroundAnterior segment cytomegalovirus (CMV) infection, which can be presented as anterior uveitis and corneal endotheliitis, has recently been reported in immunocompetent patients. We would like to access the validity of two presumed characteristic clinical profiles: profile 1, non-herpes simplex virus (HSV)/varicella zoster virus (VZV) corticosteroid-recalcitrant inflammatory ocular hypertensive syndrome (IOHS), and profile 2, corneal endotheliitis with specific coin-shaped keratic precipitates (KPs), that could be helpful in identifying CMV anterior segment intraocular infection.MethodsPatients with either profile 1 or profile 2 or both were enrolled consecutively from the uveitis service in Chang Gung Memorial Hospital, Taoyuan, between January 1, 2006 and May 31, 2010. Diagnostic anterior chamber tapping was performed and followed by real-time quantitative polymerase chain reaction (PCR) to detect herpesviridae DNA including HSV I and II, VZV, CMV, and Epstein–Barr virus.ResultsThirty-one eyes of 30 patients (21 males and nine females) were enrolled in this study. CMV DNA PCR was positive in 29 eyes of 28 patients (20 males and eight females). Nineteen of 20 eyes (19 patients) in profile 1 had positive CMV PCR. Ten of 11 eyes (11 patients) in profile 2 had positive CMV PCR. The positive predictive value of profile 1 and profile 2 was 94.7% and 90.9%, respectively. The positive predictive value of combining the two profiles was 93.3%.ConclusionsNon-HSV/ZVZ corticosteroid-recalcitrant IOHS and corneal endotheliitis with specific coin-shaped KPs could be used as the screening tool for CMV anterior segment intraocular infection.


Ocular Immunology and Inflammation | 2009

Postcataract Endophthalmitis Caused by Enterococcus faecalis

Kuan-Jen Chen; Chi-Chun Lai; Ming-Hui Sun; Tun-Lu Chen; Ko-Jen Yang; Ya-Hui Kuo; An-Ning Chao; Wei-Chi Wu

Purpose: To investigate the management strategies, susceptibility patterns, and visual outcomes of postcataract Enterococcus faecalis endophthalmitis. Methods: Retrospective chart review study of 26 eyes of 26 patients with culture-proven E. faecalis endophthalmitis. Results: In initial treatments, pars plana vitrectomy with intravitreal antibiotics in 15 eyes (58%). Resistance patterns among the isolates were the following: vancomycin in 0 of 26 eyes (0%), ampicillin in 0 of 26 eyes (0%), teicoplanin in 0 of 18 eyes (0%), and high-level gentamicin (minimum inhibitory concentration > 500 mg/L) in 8 of 12 eyes (67%). Presenting visual acuity ranged from counting fingers to no light perception. Final visual acuity was better than 5/200 in 4 of 26 eyes (15%), 5/200 to hand motions in 4 of 26 eyes (15%), and light perception to no light perception in 18 of 26 eyes (69%). Conclusions: Although all E. faecalis isolates were susceptible to vancomycin, endophthalmitis caused by E. faecalis was usually associated with poor visual prognosis.


Acta Ophthalmologica | 2010

Reducing the incidence of early postoperative vitreous haemorrhage by preoperative intravitreal bevacizumab in vitrectomy for diabetic tractional retinal detachment

Ling Yeung; Laura Liu; Wei-Chi Wu; Ya-Hui Kuo; An-Ning Chao; Kuan-Jen Chen; Ko-Jen Yang; Tun-Lu Chen; Chi-Chun Lai

Acta Ophthalmol. 2010: 88: 635–640


Retina-the Journal of Retinal and Vitreous Diseases | 2017

Serum Vascular Endothelial Growth Factor After Bevacizumab Or Ranibizumab Treatment For Retinopathy Of Prematurity.

Wei-Chi Wu; Chia-Pang Shih; Reyin Lien; Nan-Kai Wang; Yen-Po Chen; An-Ning Chao; Kuan-Jen Chen; Tun-Lu Chen; Yih-Shiou Hwang; Chi-Chun Lai

Purpose: To investigate vascular endothelial growth factor (VEGF) levels in the systemic circulation after intravitreal injections of bevacizumab (IVB) or ranibizumab (IVR) in patients with Type 1 retinopathy of prematurity (ROP). Methods: Patients who had Type 1 ROP and received IVB or IVR were enrolled. Serum samples were collected before and up to 12 weeks after IVB or IVR treatment. The main outcome measurements were serum levels of VEGF up to 12 weeks after anti-VEGF treatment. Results: In total, 10 patients with Type 1 ROP were enrolled in this study. All the eyes had complete resolution of abnormal neovascularization of ROP after IVB or IVR. In the direct comparison of IVB with IVR, serum VEGF was found to be suppressed more in patients with Type 1 ROP who received IVB treatment, compared with those who received IVR treatment (P = 0.01, P = 0.03, and P = 0.03, respectively, 2, 4, and 8 weeks after intravitreal injection). Conclusion: Serum VEGF levels in patients with Type 1 ROP were suppressed for 2 months after treatment with IVB, and VEGF levels were less affected after IVR treatment. Further studies are warranted to investigate the long-term effects of VEGF changes in ROP patients.

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Chi-Chun Lai

Memorial Hospital of South Bend

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Nan-Kai Wang

Memorial Hospital of South Bend

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Yih-Shiou Hwang

Memorial Hospital of South Bend

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An-Ning Chao

Memorial Hospital of South Bend

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Ling Yeung

Memorial Hospital of South Bend

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Lan-Hsin Chuang

Memorial Hospital of South Bend

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Yen-Po Chen

Memorial Hospital of South Bend

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K.-J. Chen

Memorial Hospital of South Bend

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