Pick Topic
Review Topic
List Experts
Examine Expert
Save Expert
  Site Guide ··   
Glaucoma: HELP
Articles by Philip P. Chen
Based on 26 articles published since 2008
||||

Between 2008 and 2019, P. P. Chen wrote the following 26 articles about Glaucoma.
 
+ Citations + Abstracts
Pages: 1 · 2
1 Editorial Is diabetes, even without retinopathy, a risk factor for glaucoma filtering surgery failure in the age of anti-fibrosis agents? 2013

Chen, Philip P. · ·Br J Ophthalmol · Pubmed #23591546.

ABSTRACT: -- No abstract --

2 Review Optical coherence tomography angiography in glaucoma. 2019

Bojikian, Karine D / Chen, Philip P / Wen, Joanne C. ·Department of Ophthalmology, University of Washington, Seattle, Washington, USA. ·Curr Opin Ophthalmol · Pubmed #30575618.

ABSTRACT: PURPOSE OF REVIEW: Optical coherence tomography angiography (OCTA) studies have demonstrated reduced microcirculation in the superficial optic nerve, peripapillary retina, and the macula of glaucoma patients. The scope of this review is to outline recent studies using OCTA in glaucoma and highlight how OCTA may help improve diagnosis and follow-up in glaucoma patients. RECENT FINDINGS: OCTA studies have provided evidence of vascular changes in the optic nerve head, peripapillary, and macula region in glaucoma in comparison to glaucoma suspects and normal eyes. Additionally, OCTA can detect longitudinal reduction of peripapillary and macula vessel density in glaucoma patients. It remains unclear whether the reduced microcirculation in glaucoma patients induces the neuronal damage or arises through reduced circulation requirements in damaged tissue. SUMMARY: OCTA is a novel imaging modality that has great potential to enhance our understanding of glaucoma and to improve our ability to detect and treat it.

3 Review Glaucoma. 2016

Gupta, Divakar / Chen, Philip P. ·Duke University School of Medicine, Durham, NC, USA. · University of Washington Medical Center, Seattle, WA, USA. ·Am Fam Physician · Pubmed #27175839.

ABSTRACT: Glaucoma is a set of irreversible, progressive optic neuropathies that can lead to severe visual field loss and blindness. The two most common forms of glaucoma, primary open-angle glaucoma and primary angle-closure glaucoma, affect more than 2 million Americans and are increasing in prevalence. Many patients with glaucoma are asymptomatic and do not know they have the disease. Risk factors for primary open-angle glaucoma include older age, black race, Hispanic origin, family history of glaucoma, and diabetes mellitus. Risk factors for primary angle-closure glaucoma include older age, Asian descent, and female sex. Advanced disease at initial presentation and treatment nonadherence put patients with glaucoma at risk of disease progression to blindness. The U.S. Preventive Services Task Force has concluded that the evidence is insufficient to assess the potential benefits and harms of screening for glaucoma in the primary care setting. Regular eye examinations for adults are recommended by the American Academy of Ophthalmology, with the interval depending on patient age and risk factors. Diagnosis of glaucoma requires careful optic nerve evaluation and functional studies assessing a patient's visual field. The goal of treatment with eye drops, laser therapy, or surgery is to slow visual field loss by lowering intraocular pressure. Family physicians can contribute to lowering morbidity from glaucoma through early identification of high-risk patients and by emphasizing treatment adherence in patients with glaucoma.

4 Review Pediatric glaucoma surgery: a report by the American Academy Of Ophthalmology. 2014

Chen, Teresa C / Chen, Philip P / Francis, Brian A / Junk, Anna K / Smith, Scott D / Singh, Kuldev / Lin, Shan C. ·Harvard Medical School, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Glaucoma Service, Boston, Massachusetts. · Department of Ophthalmology, University of Washington, Seattle, Washington. · Doheny Eye Institute, Department of Ophthalmology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California. · Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, Florida. · Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates. · Stanford University School of Medicine, Stanford, California. · Department of Ophthalmology, University of California, San Francisco, San Francisco, California. ·Ophthalmology · Pubmed #25066765.

ABSTRACT: OBJECTIVE: To review the current published literature to evaluate the success rates and long-term problems associated with surgery for pediatric glaucoma. METHODS: Literature searches of the PubMed and Cochrane Library databases were last conducted in May 2012. The search yielded 838 potentially relevant citations, of which 273 were in non-English languages. The titles and abstracts of these articles were reviewed by the authors, and 364 were selected for possible further review. Members of the Ophthalmic Technology Assessment Committee Glaucoma Panel reviewed the full text of these articles and used the 36 that met inclusion and exclusion criteria for this Ophthalmic Technology Assessment. There were no studies on the topic that provided level I evidence. The assessment included only level II and level III studies. RESULTS: Surgeons treat pediatric glaucoma most commonly with goniotomy, trabeculotomy, trabeculectomy, combined trabeculotomy and trabeculectomy, tube shunt surgery, cyclodestruction, and deep sclerectomy. Certain surgical options seem better for specific diagnoses, such as primary congenital glaucoma, aphakic glaucoma, and glaucomas associated with other ocular or systemic anomalies. CONCLUSIONS: There are many surgical options for the treatment of the pediatric glaucomas. The relative efficacy of these various procedures for particular diagnoses and clinical situations should be weighed against the specific risks associated with the procedures for individual patients.

5 Review The effect of cataract extraction on intraocular pressure. 2014

Slabaugh, Mark A / Chen, Philip P. ·Department of Ophthalmology, University of Washington, Seattle, Washington, USA. ·Curr Opin Ophthalmol · Pubmed #24463416.

ABSTRACT: PURPOSE OF REVIEW: To examine the current literature covering the long-term effect of cataract extraction on intraocular pressure (IOP). RECENT FINDINGS: As a result of the high rate of cataract surgery, the impact on IOP continues to be the subject of multiple studies in different populations. Recent publications include those that distinguish patients with open angles from those with more narrow angles, as well as prospective analyses that address the impact of regression to the mean and other types of bias on the effect of postoperative IOP lowering. SUMMARY: There are sufficient data to suggest that cataract surgery provides a lowering effect on IOP in the long term. This effect appears to be proportional to preoperative IOP. Eyes with higher preoperative IOP have the greatest average lowering, whereas eyes with IOP in the lower range of statistically normal tend to have an IOP that is unchanged from baseline or even higher following cataract surgery. In patients with narrow angles, the IOP-lowering effect appears to also be proportional to the degree of anterior chamber deepening induced by cataract surgery.

6 Review Evaluation of the anterior chamber angle in glaucoma: a report by the american academy of ophthalmology. 2013

Smith, Scott D / Singh, Kuldev / Lin, Shan C / Chen, Philip P / Chen, Teresa C / Francis, Brian A / Jampel, Henry D. ·Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates. ·Ophthalmology · Pubmed #23978623.

ABSTRACT: OBJECTIVE: To assess the published literature pertaining to the association between anterior segment imaging and gonioscopy and to determine whether such imaging aids in the diagnosis of primary angle closure (PAC). METHODS: Literature searches of the PubMed and Cochrane Library databases were last conducted on July 6, 2011. The searches yielded 371 unique citations. Members of the Ophthalmic Technology Assessment Committee Glaucoma Panel reviewed the titles and abstracts of these articles and selected 134 of possible clinical significance for further review. The panel reviewed the full text of these articles and identified 79 studies meeting the inclusion criteria, for which the panel methodologist assigned a level of evidence based on a standardized grading scheme adopted by the American Academy of Ophthalmology. Three, 70, and 6 studies were rated as providing level I, II, and III evidence, respectively. RESULTS: Quantitative and qualitative parameters defined from ultrasound biomicroscopy (UBM), anterior segment optical coherence tomography (OCT), Scheimpflug photography, and the scanning peripheral anterior chamber depth analyzer (SPAC) demonstrate a strong association with the results of gonioscopy. There is substantial variability in the type of information obtained from each imaging method. Imaging of structures posterior to the iris is possible only with UBM. Direct imaging of the anterior chamber angle (ACA) is possible using UBM and OCT. The ability to acquire OCT images in a completely dark environment allows greater sensitivity in detecting eyes with appositional angle closure. Noncontact imaging using OCT, Scheimpflug photography, or SPAC makes these methods more attractive for large-scale PAC screening than contact imaging using UBM. CONCLUSIONS: Although there is evidence suggesting that anterior segment imaging provides useful information in the evaluation of PAC, none of these imaging methods provides sufficient information about the ACA anatomy to be considered a substitute for gonioscopy. Longitudinal studies are needed to validate the diagnostic significance of the parameters measured by these instruments for prospectively identifying individuals at risk for PAC. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

7 Article Practice Preferences for Glaucoma Surgery: A Survey of the American Glaucoma Society. 2017

Vinod, Kateki / Gedde, Steven J / Feuer, William J / Panarelli, Joseph F / Chang, Ta C / Chen, Philip P / Parrish, Richard K. ·*Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, Icahn School of Medicine, New York, NY †Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, FL ‡Department of Ophthalmology, University of Washington, Seattle, WA. ·J Glaucoma · Pubmed #28692597.

ABSTRACT: PURPOSE: The purpose of this study is to assess surgical practice patterns among the American Glaucoma Society (AGS) membership. METHODS: An anonymous online survey evaluating the use of glaucoma surgeries in various clinical settings was redistributed to AGS members. Survey responses were compared with prior results from 1996, 2002, and 2008 to determine shifts in surgical practice patterns. Questions were added to assess the preferred approach to primary incisional glaucoma surgery and phacoemulsification combined with glaucoma surgery. RESULTS: A total of 252 of 1091 (23%) subscribers to the AGS-net participated in the survey. Percentage use (mean±SD) of trabeculectomy with mitomycin C (MMC), glaucoma drainage device (GDD), and minimally invasive glaucoma surgery (MIGS) as an initial surgery in patients with primary open angle glaucoma was 59%±30%, 23%±23%, and 14%±20%, respectively. Phacoemulsification cataract extraction alone was the preferred surgical approach in 44%±32% of patients with primary open angle glaucoma and visually significant cataract, and phacoemulsification cataract extraction was combined with trabeculectomy with MMC in 24%±23%, with MIGS in 22%±27%, and with GDD in 9%±14%. Although trabeculectomy was selected most frequently to surgically manage glaucoma in 8 of 8 clinical settings in 1996, GDD was preferred in 7 of 8 clinical settings in 2016. CONCLUSIONS: The use of GDD has increased and that of trabeculectomy has concurrently decreased over the past 2 decades. Trabeculectomy with MMC is the most popular primary incisional surgery when performed alone or in combination with phacoemulsification cataract extraction. Surgeons frequently manage coexistent cataract and glaucoma with cataract extraction alone, rather than as a combined cataract and glaucoma procedure.

8 Article Peripapillary Retinal Nerve Fiber Layer Vascular Microcirculation in Eyes With Glaucoma and Single-Hemifield Visual Field Loss. 2017

Chen, Chieh-Li / Bojikian, Karine D / Wen, Joanne C / Zhang, Qinqin / Xin, Chen / Mudumbai, Raghu C / Johnstone, Murray A / Chen, Philip P / Wang, Ruikang K. ·Department of Ophthalmology, University of Washington, Seattle2Department of Bioengineering, University of Washington, Seattle. · Department of Ophthalmology, University of Washington, Seattle. · Department of Bioengineering, University of Washington, Seattle. ·JAMA Ophthalmol · Pubmed #28358939.

ABSTRACT: Importance: Understanding the differences in vascular microcirculation of the peripapillary retinal nerve fiber layer (RNFL) between the hemispheres in eyes with glaucoma with single-hemifield visual field (VF) defects may provide insight into the pathophysiology of glaucoma. Objective: To investigate the changes in the microcirculation of the peripapillary RNFL of eyes with glaucoma by using optical microangiography. Design, Setting, and Participants: Eyes with glaucoma and single-hemifield VF defect and normal eyes underwent scanning using an optical microangiography system covering a 6.7 × 6.7-mm2 area centered at the optic nerve head. The RNFL microcirculation was measured within an annulus region centered at the optic nerve head divided into superior and inferior hemispheres. Blood flux index (the mean flow signal intensity in the vessels) and vessel area density (the percentage of the detected vessels in the annulus) were measured. Main Outcomes and Measures: Differences in microcirculation between the hemispheres in eyes with glaucoma and normal eyes and correlations among blood flow metrics, VF thresholds, and clinical optical coherence tomography structural measurements were assessed. Results: Twenty-one eyes from 21 patients with glaucoma (7 men and 14 women; mean [SD] age, 63.7 [9.9] years) and 20 eyes from 20 healthy control individuals (9 men and 11 women; mean [SD] age, 68.3 [10.7] years) were studied. In eyes with glaucoma, the abnormal hemisphere showed a thinner RNFL (mean [SE] difference, 23.5 [4.5] μm; 95% CI, 15.1-32.0 µm; P < .001), lower RNFL blood flux index (mean [SE] difference, 0.04 [0.01]; 95% CI, 0.02-0.05; P < .001), and less vessel area density (mean [SE] difference, 0.08% [0.02%]; 95% CI, 0.05%-0.10%; P < .001) than did the normal hemisphere. Compared with normal eyes, reduced RNFL microcirculation was found in the normal hemisphere of eyes with glaucoma, measured by mean [SE] differences in blood flux index (0.06 [0.01]; 95% CI, 0.04-0.09; P < .001) and vessel area density (0.04% [0.02%]; 95% CI, 0.02%-0.08%; P = .003) but not in RNFL thickness (3.4 [4.7] μm; 95% CI, -6.2 to 12.9 µm; P = .48). Strong correlations were found between the blood flux index and VF mean deviation (Spearman ρ = 0.44; P = .045) and RNFL thickness (Spearman ρ = 0.65; P = .001) in the normal hemisphere of the eye with glaucoma. Conclusions and Relevance: Reduced RNFL microcirculation was detected in the normal hemisphere of eyes with glaucoma, with strong correspondence with VF loss and RNFL thinning. Although the results suggest that vascular dysfunction precedes structural changes seen in glaucoma, longitudinal studies would be needed to confirm this finding.

9 Article Refractive Outcome of Cataract Surgery in Eyes With Prior Trabeculectomy: Risk Factors for Postoperative Myopia. 2017

Yeh, Oliver L / Bojikian, Karine D / Slabaugh, Mark A / Chen, Philip P. ·Department of Ophthalmology, University of Washington, Seattle, WA. ·J Glaucoma · Pubmed #27661991.

ABSTRACT: PURPOSE: To examine refractive outcomes after phacoemulsification in eyes with prior trabeculectomy. DESIGN: Retrospective observational case-control study METHODS:: Comparison of eyes of glaucoma patients undergoing cataract surgery after trabeculectomy (study group) with a matched group with medically controlled glaucoma (control group). Laser interferometry was used to obtain ocular biometry. We measured the difference between the expected and actual postoperative refraction using third-generation and fourth-generation intraocular lens (IOL) prediction formulae (Haigis, Holladay 2, Hoffer Q, and SRK-T). A residual difference of >1.0 D of hyperopia or myopia was considered a "refractive surprise." RESULTS: In total, 86 eyes (85 patients) were included, including 23 eyes (22 patients) in the study group and 63 eyes (63 patients) in the control group. The mean follow-up was 12.2±4.1 months. Eyes (n=13) with trabeculectomy and a preoperative intraocular pressure (IOP)≤9 mm Hg had significantly more large myopic surprises than the control group for all IOL formulae (P=0.015 Haigis, P=0.003 Holladay 2, P=0.004 Hoffer Q, P=0.003 SRK-T). Eyes (n=10) with trabeculectomy and preoperative IOP>9 mm Hg, however, did not have significantly more myopic errors than the control (P>0.05, all formulae). An "IOP spike" defined as a >50% rise in IOP from baseline within 1 month of cataract surgery in the subgroup with preoperative IOP≤9 mm Hg (n=8) was associated with increased risk of large myopic surprise (3/8 subset vs. 1/63 control eyes for all formulae; P=0.004 Haigis, P=0.004 Holladay 2, P=0.001 Hoffer Q, P=0.004 SRK-T) as well as for large myopic and hyperopic surprises overall (4/8 subset vs. ≤2/63 depending upon formulae; all P≤0.001). CONCLUSIONS: Low posttrabeculectomy IOP (≤9 mm Hg) is a risk factor for significant myopic surprise when undergoing subsequent cataract surgery despite using laser interferometry to measure ocular biometry and later generation formulae to determine IOL power. In addition, an IOP spike was associated with a 50% risk for large refractive surprise in this low IOP group.

10 Article Peripapillary Retinal Nerve Fiber Layer Vascular Microcirculation in Glaucoma Using Optical Coherence Tomography-Based Microangiography. 2016

Chen, Chieh-Li / Zhang, Anqi / Bojikian, Karine D / Wen, Joanne C / Zhang, Qinqin / Xin, Chen / Mudumbai, Raghu C / Johnstone, Murray A / Chen, Philip P / Wang, Ruikang K. ·Department of Bioengineering, University of Washington, Seattle, Washington, United States 2Department of Ophthalmology, University of Washington, Seattle, Washington, United States. · Department of Bioengineering, University of Washington, Seattle, Washington, United States. · Department of Ophthalmology, University of Washington, Seattle, Washington, United States. · Department of Bioengineering, University of Washington, Seattle, Washington, United States 3Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China. ·Invest Ophthalmol Vis Sci · Pubmed #27442341.

ABSTRACT: PURPOSE: To investigate the vascular microcirculation changes in the retinal nerve fiber layer (RNFL) in normal, glaucoma suspect, and open-angle glaucoma (OAG) groups using optical coherence tomography-based microangiography (OMAG). METHODS: One eye from each subject was scanned with a Cirrus HD-OCT 5000-based OMAG prototype system montage scanning protocol centered at the optic nerve head (ONH). Blood flow signals were extracted using OMAG algorithm. Retinal nerve fiber layer vascular microcirculation was measured by calculating the blood flux index and vessel area density within a 1.2-mm width annulus centered at the ONH with exclusion of big retinal vessels. One-way ANOVA were performed to analyze the RNFL microcirculation among groups. Linear-regression models were constructed to analyze the correlation between RNFL microcirculation and clinical parameters. Discrimination capabilities of the flow metrics were assessed with the area under the receiver operating characteristic curve (AROC). RESULTS: Twenty normal, 26 glaucoma suspect, and 42 OAG subjects were enrolled. Eyes from OAG subjects and glaucoma suspects showed significantly lower blood flux index compared with normal eyes (P ≤ 0.0015). Retinal nerve fiber layer blood flow metrics showed significant correlations with visual field indices and structural changes in glaucomatous eyes (P ≤ 0.0123). Similar discrimination capability of blood flux index compared with RNFL thickness was found in both disease groups. CONCLUSIONS: Peripapillary RNFL vascular microcirculation measured as blood flux index by OMAG showed significant differences among OAG, glaucoma suspect, and normal controls and was significantly correlated with functional and structural defects. Retinal nerve fiber layer microcirculation measurement using OMAG may help physicians monitor glaucoma.

11 Article Lamina depth and thickness correlate with glaucoma severity. 2016

Kim, Martha / Bojikian, Karine D / Slabaugh, Mark A / Ding, Leona / Chen, Philip P. ·Department of Ophthalmology, Dongguk University Ilsan Hospital, Goyang, Korea; Department of Ophthalmology, University of Washington, Seattle, WA, USA, . · Department of Ophthalmology, University of Washington, Seattle, WA, USA. ·Indian J Ophthalmol · Pubmed #27380974.

ABSTRACT: PURPOSE: To evaluate the correlation between lamina cribrosa (LC) morphology and glaucoma severity in patients with primary forms of open-angle glaucoma (OAG) using enhanced depth imaging spectral-domain optical coherence tomography (SD-OCT) and Humphrey visual field test (HVF). SUBJECTS AND METHODS: Patients with OAG (n = 166), divided into normal-tension glaucoma (NTG) and high-tension glaucoma (HTG) groups (n = 66 and n = 100), were imaged using SD-OCT to obtain horizontal B-scan images of the optic nerve head (ONH). Laminar depth (LD) and laminar thickness (LT) were measured at the center of ONH. RESULTS: The mean (±standard deviation) values of LD, LT, and visual field mean deviation (MD) were 555.4 ± 142.3 μm, 179.9 ± 49.7 μm, and - 5.7 ± 6.4 dB, respectively. In the multivariate linear regression analysis, LD, LT, and intraocular pressure (IOP) were significantly correlated with MD (P = 0.007, P = 0.037, and P = 0.004, respectively). In the subgroup analyses, only LD was associated with MD in the NTG group (n = 66), whereas LT and IOP were correlated with MD in the HTG group (n = 100). Neither axial length nor central corneal thickness was associated with LD or LT. CONCLUSIONS: Glaucoma severity, as measured by HVF MD, shows significant correlations with LD and LT, with greater severity associated with increasing LD and decreasing LT. Normal- and high-tension OAG patients have different associations with LD and LT, which implies that the pathogenesis of these two entities might be different.

12 Article Combined Ahmed Glaucoma Valve Placement, Intravitreal Fluocinolone Acetonide Implantation and Cataract Extraction for Chronic Uveitis. 2016

Chang, Ingrid T / Gupta, Divakar / Slabaugh, Mark A / Vemulakonda, Gurunadh A / Chen, Philip P. ·Department of Ophthalmology, University of Washington, Seattle, WA. ·J Glaucoma · Pubmed #27300641.

ABSTRACT: PURPOSE: To report the outcomes of combined Ahmed glaucoma valve (AGV) placement, intravitreal fluocinolone acetonide implant, and cataract extraction procedure in the treatment of chronic noninfectious uveitis. PATIENTS AND METHODS: Retrospective case series of patients with chronic noninfectious uveitis who underwent AGV placement, intravitreal fluocinolone acetonide implantation, and cataract extraction in a single surgical session performed at 1 institution from January 2009 to November 2014. Outcome measures included intraocular pressure (IOP) and glaucoma medication use. Secondary outcome measures included visual acuity, systemic anti-inflammatory medications, number of uveitis flares, and complications. RESULTS: Fifteen eyes of 10 patients were studied, with a mean age of 40.3±15.7 and mean follow-up duration of 26 months (range, 13 to 39 mo). Before surgery, the IOP was 18.5±7.3 mm Hg and patients were using 1.5±1.5 topical glaucoma medications. At the 12-month follow-up, IOP was 12.8±3.2 mm Hg (P=0.01) and patients were using 0.5±0.8 (P=0.03) topical glaucoma medications. At 36 months of follow-up, late, nonsustained hypotony had occurred in 3 eyes (20%), and 1 eye (6%) had received a second AGV for IOP control. Before treatment, patients had 2.7±1.5 uveitis flares in the year before surgery while on an average of 2.1±0.6 systemic anti-inflammatory medications, which decreased to an average of 0.1±0.3 (P<0.01) flares the year after surgery while on an average of 0.4±1.1 (P<0.01) systemic medications. CONCLUSION: Combined AGV, intravitreal fluocinolone acetonide implant, and cataract extraction is effective in controlling IOP and reducing the number of glaucoma medications at 12 months after treatment in patients with chronic uveitis.

13 Article Optic Disc Perfusion in Primary Open Angle and Normal Tension Glaucoma Eyes Using Optical Coherence Tomography-Based Microangiography. 2016

Bojikian, Karine D / Chen, Chieh-Li / Wen, Joanne C / Zhang, Qinqin / Xin, Chen / Gupta, Divakar / Mudumbai, Raghu C / Johnstone, Murray A / Wang, Ruikang K / Chen, Philip P. ·Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America. · Department of Bioengineering, University of Washington, Seattle, Washington, United States of America. · Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China. ·PLoS One · Pubmed #27149261.

ABSTRACT: PURPOSE: To investigate optic disc perfusion differences in normal, primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG) eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique. DESIGN: Cross-sectional, observational study. SUBJECTS: Twenty-eight normal, 30 POAG, and 31 NTG subjects. METHODS: One eye from each subject was scanned with a 68 kHz Cirrus HD-OCT 5,000-based OMAG prototype system centered at the optic nerve head (ONH) (Carl Zeiss Meditec Inc, Dublin, CA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program. MAIN OUTCOME MEASURES: Optic disc perfusion, quantified as flux, vessel area density, and normalized flux (flux normalized by the vessel area) within the ONH. RESULTS: Glaucomatous eyes had significantly lower optic disc perfusion in preLC in all three perfusion metrics (p<0.0001) compared to normal eyes. The visual field (VF) mean deviation (MD) and pattern standard deviation (PSD) were similar between the POAG and NTG groups, and no differences in optic disc perfusion were observed between POAG and NTG. Univariate analysis revealed significant correlation between optic disc perfusion and VF MD, VF PSD, and rim area in both POAG and NTG groups (p≤0.0288). However, normalized optic disc perfusion was correlated with some structural measures (retinal nerve fiber layer thickness and ONH cup/disc ratio) only in POAG eyes. CONCLUSIONS: Optic disc perfusion detected with OMAG was significantly reduced in POAG and NTG groups compared to normal controls, but no difference was seen between POAG and NTG groups with similar levels of VF damage. Disc perfusion was significantly correlated with VF MD, VF PSD, and rim area in glaucomatous eyes. Vascular changes at the optic disc as measured using OMAG may provide useful information for diagnosis and monitoring of glaucoma.

14 Article Refusal of Trabeculectomy for the Fellow Eye in Collaborative Initial Glaucoma Treatment Study (CIGTS) Participants. 2016

Gupta, Divakar / Musch, David C / Niziol, Leslie M / Chen, Philip P. ·Duke Eye Center, Duke University Medical Center, Durham, North Carolina. Electronic address: divakar.gupta@duke.edu. · Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan; Department of Epidemiology, University of Michigan, Ann Arbor, Michigan. · Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan. · Department of Ophthalmology, University of Washington, Seattle, Washington. ·Am J Ophthalmol · Pubmed #27013068.

ABSTRACT: PURPOSE: To understand the reasons for refusal of fellow eye surgical treatment for glaucoma after first eye trabeculectomy. DESIGN: Post hoc analysis of data collected in a multicenter, randomized clinical trial. METHODS: Data from participants in the Collaborative Initial Glaucoma Treatment Study (CIGTS) who were randomized to and underwent initial trabeculectomy on their study eye, and whose fellow eye was eligible for surgical treatment, were analyzed. Participant demographic data and characteristics, surgical data from the study eye, and quality-of-life survey results were compared between groups that received or refused trabeculectomy in their fellow eye. The main outcome measure was patient refusal of fellow eye surgery for glaucoma. RESULTS: Of 159 participants who were randomized to and underwent trabeculectomy on their study eye and had a fellow eye that was eligible for surgery, 30 (19%) refused fellow eye surgery. Eligible patients who refused fellow eye trabeculectomy did not differ significantly in visual function or local eye symptoms from those that underwent fellow eye trabeculectomy (all P > .05). In a multivariable analysis of data, increased fellow eye preoperative intraocular pressure (IOP) was associated with decreased odds (OR = 0.89, P = .0188), study eye hypotony at 3 months postoperatively was associated with increased odds (OR = 7.24, P = .0125), and argon suture lysis procedure was associated with decreased odds (OR = 0.38, P = .0385) of surgery refusal. CONCLUSIONS: Refusal of fellow eye surgery was not uncommonly encountered in the CIGTS. Those who refused fellow eye surgery had lower fellow eye IOP and were more likely to have had hypotony after study eye trabeculectomy.

15 Article Incidence and risk factors for traumatic intraocular pressure elevation and traumatic glaucoma after open-globe injury. 2015

Bojikian, K D / Stein, A L / Slabaugh, M A / Chen, P P. ·Department of Ophthalmology, University of Washington, Seattle, WA, USA. ·Eye (Lond) · Pubmed #26381097.

ABSTRACT: PURPOSE: To examine traumatic intraocular pressure (IOP) elevation and glaucoma after open-globe injury. DESIGN: Retrospective, observational case series. METHODS: Review of patients with open-globe repair at the University of Washington from May 1997 through July 2010. Traumatic IOP elevation and glaucoma were defined respectively as intraocular pressure (IOP) ≥22 mm Hg at >1 visit or need for glaucoma medication, and long-term (at least 3 months) glaucoma medication use or glaucoma surgery. RESULTS: We included 515 eyes (515 patients). The mean follow-up was 12.6±20.1 months. One hundred twenty eyes (23.3%) developed traumatic IOP elevation, of which 32 (6.2%) developed glaucoma; six eyes (1.2%) required glaucoma surgery. The mean time to development of traumatic IOP elevation was 1.5±3.4 months (range 1 day to 2 years). Kaplan-Meier 6- and 12-month estimates for development of traumatic IOP elevation were 27.2 and 32.4%, respectively, and for development of traumatic glaucoma were 7.1 and 11.0%, respectively. Multivariate regression revealed associations between traumatic IOP elevation and older age, and traumatic glaucoma and prior penetrating keratoplasty, initial vitreous hemorrhage, Zone II injury, and penetrating keratoplasty after open-globe repair. Traumatic glaucoma was controlled (IOP <22 mm Hg) in 78.1% of eyes at final follow-up, with mean IOP of 18.2 mm Hg on 1.7 medications. CONCLUSIONS: Traumatic IOP elevation and glaucoma were common after visually salvageable open-globe injury. Most cases developed within 6 months, although longer follow-up remains important for case detection. Penetrating keratoplasty before or after repair, and vitreous hemorrhage were notable risk factors.

16 Article The Effect of Phacoemulsification on Intraocular Pressure in Glaucoma Patients: A Report by the American Academy of Ophthalmology. 2015

Chen, Philip P / Lin, Shan C / Junk, Anna K / Radhakrishnan, Sunita / Singh, Kuldev / Chen, Teresa C. ·Department of Ophthalmology, University of Washington, Seattle, Washington. · Department of Ophthalmology, University of California, San Francisco, San Francisco, California. · Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami; Miami Veterans Affairs Medical Center, Miami, Florida. · Glaucoma Center of San Francisco; Glaucoma Research and Education Group, San Francisco, California. · Stanford University School of Medicine, Stanford, California. · Harvard Medical School, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Glaucoma Service, Boston, Massachusetts. ·Ophthalmology · Pubmed #25943711.

ABSTRACT: OBJECTIVE: To examine effects of phacoemulsification on longer-term intraocular pressure (IOP) in patients with medically treated primary open-angle glaucoma (POAG; including normal-tension glaucoma), pseudoexfoliation glaucoma (PXG), or primary angle-closure glaucoma (PACG), without prior or concurrent incisional glaucoma surgery. METHODS: PubMed and Cochrane database searches, last conducted in December 2014, yielded 541 unique citations. Panel members reviewed titles and abstracts and selected 86 for further review. The panel reviewed these articles and identified 32 studies meeting the inclusion criteria, for which the panel methodologist assigned a level of evidence based on standardized grading adopted by the American Academy of Ophthalmology. One, 15, and 16 studies were rated as providing level I, II, and III evidence, respectively. RESULTS: All follow-up, IOP, and medication data listed are weighted means. In general, the studies reported on patients using few glaucoma medications (1.5-1.9 before surgery among the different diagnoses). For POAG, 9 studies (total, 461 patients; follow-up, 17 months) showed that phacoemulsification reduced IOP by 13% and glaucoma medications by 12%. For PXG, 5 studies (total, 132 patients; follow-up, 34 months) showed phacoemulsification reduced IOP by 20% and glaucoma medications by 35%. For chronic PACG, 12 studies (total, 495 patients; follow-up, 16 months) showed phacoemulsification reduced IOP by 30% and glaucoma medications by 58%. Patients with acute PACG (4 studies; total, 119 patients; follow-up, 24 months) had a 71% reduction from presenting IOP and rarely required long-term glaucoma medications when phacoemulsification was performed soon after medical reduction of IOP. Trabeculectomy after phacoemulsification was uncommon; the median rate reported within 6 to 24 months of follow-up in patients with controlled POAG, PXG, or PACG was 0% and was 7% in patients with uncontrolled chronic PACG. CONCLUSIONS: Phacoemulsification typically results in small, moderate, and marked reductions of IOP and medications for patients with POAG, PXG, and PACG, respectively, and using 1 to 2 medications before surgery. Trabeculectomy within 6 to 24 months after phacoemulsification is rare in such patients. However, reports on its effects in eyes with advanced disease or poor IOP control before surgery are few, particularly for POAG and PXG.

17 Article Prevalence of self-reported early glaucoma eye drop bottle exhaustion and associated risk factors: a patient survey. 2014

Moore, Daniel B / Walton, Charlene / Moeller, Kristy L / Slabaugh, Mark A / Mudumbai, Raghu C / Chen, Philip P. ·Department of Ophthalmology, University of Washington, 325 Ninth Ave, Seattle, WA 98104-2499, USA. pchen@uw.edu. ·BMC Ophthalmol · Pubmed #24927769.

ABSTRACT: BACKGROUND: One barrier to patient adherence with chronic topical glaucoma treatment is an inadequate amount of medication available between prescription refills. We examined the self-reported prevalence of early exhaustion of glaucoma eye drops prior to a scheduled refill, and associated risk factors. METHODS: This cross-sectional survey was performed at a University-based clinical practice. Glaucoma patients at the University of Washington who were experienced with eye drop application and were on a steady regimen of self-administered glaucoma drops in both eyes took a survey at the time of clinic examination. The main outcome measure was self-reported early eye drop bottle exhaustion. RESULTS: 236 patients were eligible and chose to participate. In general, patients included were relatively healthy (mean 2.3 comorbid medical conditions). Sixty patients (25.4%) reported any problem with early exhaustion of eye drop bottles, and this was associated with visual acuity ≤ 20/70 in the better eye (P = .049). Twelve patients (5.1%) reported that they "often" (5-7 times per year), "usually" (8-11 times per year) or "always" ran out of eye drops prior to a scheduled refill. Patients affected by this higher level (≥ 5 times yearly) of eye drop bottle exhaustion were more likely to have poor visual acuity in their worse eye ≤  20/70 (P = .015) and had significantly lower worse-eye logMAR (P = .043). CONCLUSIONS: Self-reported early glaucoma bottle exhaustion regularly affected 5% of patients in our population and 25% reported early exhaustion at least once; the main risk factor was poor vision in at least one eye. These results may not be generalizable to a broad patient population, or to those inexperienced with eye drop self-administration. However, this pilot study compels further evaluation and consideration of early eye drop bottle exhaustion in glaucoma patients.

18 Article Risk factors for acute postoperative intraocular pressure elevation after phacoemulsification in glaucoma patients. 2014

Slabaugh, Mark A / Bojikian, Karine D / Moore, Daniel B / Chen, Philip P. ·From the Department of Ophthalmology (Slabaugh, Bojikian, Moore, Chen), University of Washington, Seattle, Washington · the Department of Ophthalmology (Bojikian), Federal University of São Paulo, São Paulo, Brazil. ·J Cataract Refract Surg · Pubmed #24440104.

ABSTRACT: PURPOSE: To evaluate the risk factors for and frequency of an acute intraocular pressure (IOP) elevation (spike) after phacoemulsification in patients with glaucoma. SETTING: Academic glaucoma clinics and operating rooms. DESIGN: Retrospective case series. METHODS: Charts of consecutive glaucoma patients without previous incisional glaucoma surgery having phacoemulsification by the same surgeon between August 1996 and July 2012 were reviewed to obtain demographic information, preoperative glaucoma medications, severity and treatment measures, intraoperative course, and postoperative outcomes. A postoperative IOP spike was defined as IOP greater than 50% above baseline IOP. Main outcome measures were the number of eyes with a postoperative IOP spike and risk factors associated with an IOP spike after phacoemulsification. RESULTS: Of 271 eyes (271 patients) included in the study, 45 (17%) had an IOP spike. Risk factors for postoperative IOP spike by multivariate analysis included longer axial length (AL) or associated characteristics (wider angle grade on gonioscopy, deeper anterior chamber, and male sex), higher number of preoperative IOP-lowering medications, previous laser trabeculoplasty, and lack of postoperative oral acetazolamide. One eye (0.4%) required trabeculectomy during the 90-day postoperative period. CONCLUSIONS: A significant proportion of glaucoma patients having phacoemulsification had an IOP spike. Patients requiring a higher number of IOP-lowering medications or laser trabeculoplasty for IOP control preoperatively and those with a greater AL should be treated more aggressively with IOP-lowering medication in the immediate postoperative period. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

19 Article The effect of phacoemulsification on intraocular pressure in medically controlled open-angle glaucoma patients. 2014

Slabaugh, Mark A / Bojikian, Karine D / Moore, Daniel B / Chen, Philip P. ·Department of Ophthalmology, University of Washington, Seattle, Washington. Electronic address: mas12@uw.edu. · Department of Ophthalmology, University of Washington, Seattle, Washington. ·Am J Ophthalmol · Pubmed #24182743.

ABSTRACT: PURPOSE: To evaluate intraocular pressure (IOP) after phacoemulsification in patients with medically controlled open-angle glaucoma (OAG), and examine the association of biometric variables to IOP changes. DESIGN: Retrospective case series. METHODS: Open-angle glaucoma patients without prior incisional glaucoma surgery undergoing phacoemulsification by a single surgeon between January 1997 and October 2011 were evaluated. Patient charts were reviewed to obtain demographic information, preoperative glaucoma medications, severity and treatment measures, and preoperative and postoperative IOP. RESULTS: A total of 157 eyes (157 patients) were included in the study. The average preoperative IOP of 16.3 ± 3.6 mm Hg decreased to 14.5 ± 3.4 mm Hg at 1 year (P < .001). Sixty eyes (38%) required additional medications or laser for IOP control within the first year postoperatively, or had a higher IOP at postoperative year 1 without medication change. Among eyes without postoperative medication changes (n = 102), higher preoperative IOP (P < .001), older age (P = .006), and deeper anterior chamber depth (P = .015) were associated with lower postoperative IOP. CONCLUSIONS: Phacoemulsification resulted in a small average decrease in IOP in patients with OAG. A sizeable proportion of medically controlled glaucoma patients with open angles undergoing phacoemulsification experienced an increase in IOP or required more aggressive treatment to control IOP postoperatively.

20 Article Glaucoma in patients with ocular chemical burns. 2012

Lin, Michelle P / Ekşioğlu, Ümit / Mudumbai, Raghu C / Slabaugh, Mark A / Chen, Philip P. ·Department of Ophthalmology, University of Washington School of Medicine, Seattle, Washington 98104-2499, USA. ·Am J Ophthalmol · Pubmed #22633350.

ABSTRACT: PURPOSE: To examine the development and management of glaucoma in patients with ocular chemical burns. DESIGN: Retrospective, observational case series. METHODS: setting: University of Washington Eye Clinics. patient population: Twenty-nine eyes (18 patients) with ocular chemical burns seen between 1997 and 2010 with a minimum of 3 months of follow-up. observation procedure: Eyes were graded using the Roper-Hall scale. main outcome measures: Long-term use of glaucoma medications (3 months or more) and need for glaucoma surgery. RESULTS: The mean age was 45 ± 17 years, with a mean follow-up of 75 ± 47 months (median, 66 months). Roper-Hall grade III or IV eyes (n = 20) had significantly higher intraocular pressure at presentation (35.9 vs 16.4 mm Hg; P = .001) and over follow-up were more likely to require long-term glaucoma medications (P = .003) or to undergo glaucoma surgery (P = .016) than Roper-Hall grade I or II eyes. Thirteen eyes (12 Roper-Hall grade III or IV) underwent glaucoma surgery. Eight eyes underwent glaucoma tube implant surgery; 4 required at least 1 revision. Seven eyes underwent diode laser cyclophotocoagulation; 4 required repeat treatment. Most (89%) eyes had controlled intraocular pressure at the last follow-up. However, 76% of eyes with visual acuity of 20/200 or worse at initial evaluation did not have improved vision at the last follow-up. CONCLUSIONS: Eyes with Roper-Hall grade III or IV ocular chemical burns were more likely to have glaucoma and to require surgery for it. Outcomes of glaucoma management generally were good, although tube implant surgeries often had complications requiring revision.

21 Article Practice preferences for glaucoma surgery: a survey of the American Glaucoma Society in 2008. 2011

Desai, Manishi A / Gedde, Steven J / Feuer, William J / Shi, Wei / Chen, Philip P / Parrish, Richard K. ·Boston Medical Center, Boston University School of Medicine, Boston, Massachusetts, USA. ·Ophthalmic Surg Lasers Imaging · Pubmed #21563745.

ABSTRACT: BACKGROUND AND OBJECTIVE: To evaluate glaucoma surgical practice patterns among members of the American Glaucoma Society (AGS). PATIENTS AND METHODS: An anonymous web-based survey was sent to AGS members to determine their preferred surgical approach in ten clinical settings. Survey results were compared with those from 1996 and 2002. RESULTS: A total of 125 (22%) AGS members responded to the survey. Mean glaucoma drainage device (GDD) usage increased from 17.5% (range: 5% to 37%; standard deviation [SD]: 10.9%) in 1996 to 50.8% (range: 15% to 76%; SD: 17.3%) in 2008, and mean trabeculectomy usage decreased from 80.8% (range: 62% to 93%; SD: 11.3%) in 1996 to 45.5% (range: 16% to 80%; SD: 17.9) in 2008. GDD was most popular in none of 8 clinical settings in 1996, and 5 of 8 clinical settings in 2008. Mitomycin C was selected as an adjunctive antifibrotic agent to trabeculectomy in 85% to 99% of cases. CONCLUSION: Glaucoma surgical practice patterns have changed since 1996. The use of a GDD has progressively increased, and the popularity of trabeculectomy decreased between 1996 and 2008. Mitomycin C remains the most frequently selected antifibrotic agent used as an adjunct to trabeculectomy.

22 Article The effect of early posttrabeculectomy intraocular pressure spike in the collaborative initial glaucoma treatment study. 2011

Chen, Philip P / Musch, David C / Niziol, Leslie M. ·Department of Ophthalmology, University of Washington, 359608, Seattle, WA 98104-2499, USA. pchen@u.washington.edu ·J Glaucoma · Pubmed #20577103.

ABSTRACT: PURPOSE: To examine effects of early postoperative intraocular pressure (IOP) spike in patients undergoing primary trabeculectomy in the Collaborative Initial Glaucoma Treatment Study. PATIENTS AND METHODS: We identified patients with IOP spike ≥5 mm Hg above the baseline IOP on postoperative day 1 and those without IOP increase. The mean deviation (MD), pattern standard deviation (PSD), and corrected PSD of the visual field (VF) were compared at 6 months and years 1, 2, 3, and 5 after surgery, as was the IOP. RESULTS: Seventeen of 300 patients (5.7%) had IOP spike. After controlling for baseline VF severity in a generalized linear regression model that addressed change in MD, PSD, and corrected PSD, or in a logistic regression model for ≥3 dB of MD change, comparison between the groups revealed no significant difference at all time points examined (P>0.05). Patients with IOP spike had significantly higher mean IOP at years 3 and 5 of follow-up (P≤0.04). CONCLUSIONS: Among Collaborative Initial Glaucoma Treatment Study patients, early posttrabeculectomy IOP spike ≥5 mm Hg above baseline IOP was not associated with subsequent VF loss, but was associated with significantly higher IOP during long-term follow-up.

23 Article Continued visual field progression in eyes with prior visual field progression in patients with open-angle glaucoma. 2010

Chen, Philip P / Cady, Robert Samuel / Mudumbai, Raghu C / Ngan, Rose. ·Department of Ophthalmology, University of Washington, Seattle, USA. pchen@u.washington.edu ·J Glaucoma · Pubmed #20179616.

ABSTRACT: PURPOSE: To evaluate continued visual field (VF) progression in eyes with prior VF progression from open-angle glaucoma, using event-based criteria. METHODS: Retrospective observational case series of 70 eyes (70 patients) with open-angle glaucoma, treated for at least 2 years, that had earlier shown 1 step of VF progression. Further VF progression required a worsening of 3 adjacent points at the same location on 2 consecutive VF tests. Potential risk factors for continued progression were evaluated. RESULTS: The mean follow-up was 127±43 months. Thirty-seven eyes (55%) continued to progress. At 5, 10, and 15 years after the initial VF, the Kaplan-Meier estimate of the risk of developing 2 steps of progression was 18%, 53%, and 71%. A shorter time to the first step of progression was significantly associated with further progression (P<0.001), as was slope of the VF mean deviation (P<0.001) and pattern standard deviation (P=0.041). Eyes with further progression had higher mean IOP after the first step of progression (P=0.026). Among 37 eyes with 2 steps of progression, the estimate of the risk of progressing further was 32% at 10 years after the initial VF. CONCLUSION: Eyes with a relatively shorter time to initial VF progression from open-angle glaucoma are likely to continue to progress over long-term follow-up. More aggressive treatment in such eyes might reduce the likelihood of further VF progression.

24 Minor Orbital extension of anterior uveal melanoma after Baerveldt tube shunt implantation. 2014

Sweeney, Adam R / Keene, C Dirk / Klesert, Todd R / Jian-Amadi, Arash / Chen, Philip P. ·University of Washington, Seattle, Wash. · University of Washington, Seattle, Wash.. Electronic address: pchen@u.washington.edu. ·Can J Ophthalmol · Pubmed #25433745.

ABSTRACT: -- No abstract --

25 Minor Reply: Intraocular pressure spike prophylaxis in glaucoma patients 1 day after phacoemulsification. 2014

Slabaugh, Mark A / Bojikian, Karine D / Moore, Daniel B / Chen, Philip P. · ·J Cataract Refract Surg · Pubmed #24857452.

ABSTRACT: -- No abstract --

Next