Browse Health
Ophthalmologist (eyes)
8 years of experience
Accepting new patients

Education ?

Medical School Score Rankings
Columbia University (2002)
  • Currently 4 of 4 apples
Top 25%

Awards & Distinctions ?

Associations
American Academy of Ophthalmology
American Board of Ophthalmology

Affiliations ?

Dr. Chang is affiliated with 14 hospitals.

Hospital Affilations

Score

Rankings

  • Sutter Roseville Medical Center
    1 Medical Plaza Dr, Roseville, CA 95661
    • Currently 4 of 4 crosses
    Top 25%
  • Doctors Hospital of Manteca
    1205 E North St, Manteca, CA 95336
    • Currently 4 of 4 crosses
    Top 25%
  • Sutter Memorial Hospital
    2801 L St, Sacramento, CA 95816
    • Currently 4 of 4 crosses
    Top 25%
  • Mercy San Juan Medical Center
    6501 Coyle Ave, Carmichael, CA 95608
    • Currently 4 of 4 crosses
    Top 25%
  • Sutter General Hospital
    2801 L St, Sacramento, CA 95816
    • Currently 4 of 4 crosses
    Top 25%
  • Mercy General Hospital
    4001 J St, Sacramento, CA 95819
    • Currently 4 of 4 crosses
    Top 25%
  • NorthBay Medical Center
    1200 B Gale Wilson Blvd, Fairfield, CA 94533
    • Currently 3 of 4 crosses
    Top 50%
  • Memorial Medical Center Modesto
    1700 Coffee Rd, Modesto, CA 95355
    • Currently 3 of 4 crosses
    Top 50%
  • Doctors Medical Center of Modesto
    1441 Florida Ave, Modesto, CA 95350
    • Currently 2 of 4 crosses
  • St. Joseph's Medical Center of Stockton
    1800 N California St, Stockton, CA 95204
    • Currently 2 of 4 crosses
  • Mendocino Coast Disthosp
  • Sutter Medical Center- Sacramento
    5151 F St, Sacramento, CA 95819
  • Sutter Medical Center
  • Mercy General Hospital - Sacramento
  • Publications & Research

    Dr. Chang has contributed to 31 publications.
    Title Prospective One-year Study of Ranibizumab for Predominantly Hemorrhagic Choroidal Neovascular Lesions in Age-related Macular Degeneration.
    Date October 2010
    Journal Retina (philadelphia, Pa.)
    Excerpt

    To determine the safety and effect of ranibizumab on predominantly hemorrhagic choroidal neovascular lesions due to age-related macular degeneration.

    Title Photodynamic Therapy for Chronic Pigment Epithelial Detachment in Central Serous Chorioretinopathy.
    Date July 2009
    Journal Canadian Journal of Ophthalmology. Journal Canadien D'ophtalmologie
    Title Breast Conserving Surgery for Multifocal Breast Cancer.
    Date January 2009
    Journal Annals of Surgery
    Excerpt

    The purpose of this study is to examine the oncological safety of breast conserving surgery (BCS) for patients with multifocal breast cancer.

    Title The Surgical Management of Cataract: Barriers, Best Practices and Outcomes.
    Date September 2008
    Journal International Ophthalmology
    Excerpt

    Cataract is the leading cause of blindness in the world. Cataract surgery has been shown by multiple studies to be one of the most cost-effective health interventions, and leads to a dramatic increase in quality of life and productivity for many patients. Though there has been marked improvement in the last several decades, surgical delivery services in developing nations are still suboptimal, and a large backlog in cataract cases continues to grow. To decrease this backlog, barriers to surgery, such as direct and indirect patient costs, geographic access to surgical facilities and surgeons, cultural factors, and patient education, must be addressed. In particular, access to services by women and rural patients needs to be improved. It is clear that extracapsular techniques are cost-effective and lead to better post-operative outcomes than intracapsular cataract extraction with aphakic correction. In addition, monitoring surgical outcomes is essential for improving the quality of surgical services. However, other issues regarding the delivery of cataract surgical services, including the role of average power intraocular lenses and the role of non-physician surgeons, are yet unresolved. Information about the true cost of surgery, including costs of surgeon training, equipment, and patient outreach programs, is needed so that the goal of self-sustaining programs may be obtained.

    Title Sentinel Node Biopsy in Patients with Multiple Breast Cancer.
    Date July 2008
    Journal Breast Cancer Research and Treatment
    Excerpt

    BACKGROUND: Multicentric or multifocal breast cancer is considered a limitation for sentinel lymph node biopsy (SLNB). Studies showing that all quadrants of the breast drain via common afferent lymphatic channels indicate that multiple tumors do not affect lymphatic drainage. We therefore assessed the accuracy of SLNB in patients with multiple breast tumors. METHODS: Of the 942 breast cancer patients who underwent SLNB using radioisotope at Asan Medical Center between January 2003 and December 2006, 803 had unifocal and 139 had multiple tumors. Axillary dissection after SLNB was performed on 884 patients, 757 with unifocal and 127 with multiple tumors. All patients underwent lymphatic scintigram for removal of sentinel lymph nodes (SLNs). The clinical characteristics and accuracy of SLNB was compared in patients with unifocal and multiple breast cancer. RESULTS: In the multiple tumor group, 2.68 +/- 0.84 SLNs were identified in 136 of 139 patients (identification rate, 97.84%); 81.5% of SLNs were identified by scintigram. The incidence of axillary metastases was 29.50% (41/139). SLNB accuracy was 97.63% (124/127), with a false negative (FN) rate of 7.89% (3/38). In the unifocal group, 2.67 +/- 0.96 SLNs were identified in 787 of 803 patients (identification rate, 98.00%); 84.8% of SLNs were identified by scintigram. The incidence of axillary metastasis was 22.04% (177/803). SLNB accuracy was 98.02% (742/757), with a FN rate of 8.62% (15/174). The accuracy and FN rate of SLNB did not differ significantly between unifocal and multiple breast cancer. CONCLUSION: The accuracy of SLNB in multiple breast cancer is comparable to its accuracy in unifocal cancer. These findings indicate that SLNB can be used an as alternative to complete axillary lymph node dissection in patients with multiple breast tumors.

    Title Racial Differences and Other Risk Factors for Incidence and Progression of Age-related Macular Degeneration: Salisbury Eye Evaluation (see) Project.
    Date July 2008
    Journal Investigative Ophthalmology & Visual Science
    Excerpt

    PURPOSE: To evaluate risk factors for the incidence and progression of age-related macular degeneration (AMD) in a racially heterogeneous, geriatric population. METHODS: Subjects (n = 2240) aged 65 to 84 years underwent 2 examinations separated by 2 years, of which 1937 subjects (85%) were included in this report. Fundus photographs were performed at each examination and were graded by trained readers. Multivariate logistic regression models adjusted for age, sex, race, and clustering between eyes were used to evaluate risk factors for AMD incidence and progression. RESULTS: Smoking was a strong, dose-dependent, risk factor for progression from medium size drusen to large drusen or pigmentary abnormalities within the central 1500-microm macular zone. Smoking was also a strong risk factor for development of incident focal pigmentation within 3000 microm of the foveal center. White participants were significantly more likely than blacks to develop large drusen and focal pigmentation and to progress from medium- to large-sized drusen or pigment abnormalities within the central 1500 microm macular zone. However, whites did not have an increased risk of progression from large drusen or pigment abnormalities within the central 1500-microm perimacular zone to foveal GA or CNV when compared with blacks. CONCLUSIONS: Smoking and race are important risk factors for progression from medium to large drusen or to pigment abnormalities within the central 1500-microm macular zone. Limitations in the power of this study preclude assessment of the roles of smoking and race on the ultimate progression to foveal GA or CNV once central large drusen or pigment abnormalities are present.

    Title Vpr is Required for Efficient Nef Expression from Unintegrated Human Immunodeficiency Virus Type 1 Dna.
    Date November 2007
    Journal Journal of Virology
    Excerpt

    Unintegrated human immunodeficiency virus (HIV) DNA are viral DNA products formed naturally during HIV replication. While the integrated proviral DNA form is transcriptionally active and results in productive infection, unintegrated DNA is also capable of expression of viral RNA and proteins. Previously, we showed that HIV Vpr enhances expression from integrase-defective HIV. Here we show that Vpr activation of expression is partially dependent upon the presence of a transcriptionally active HIV promoter and results in increased transcription of unspliced gag and spliced nef viral RNA. While Tat is detectable during infection with integrase-defective HIV, Tat levels are not affected by the presence of Vpr. Mutation studies reveal that Tat is dispensable for the Vpr-mediated enhancement of expression from unintegrated DNA. We find that virion-associated Vpr is sufficient for Nef expression from unintegrated viral DNA, resulting in the efficient downregulation of CD4 from the surface of infected cells. These results provide a mechanism by which Nef expression from unintegrated HIV type 1 DNA expression occurs.

    Title Patients' Preferences in Choosing Therapy for Retinal Vein Occlusions.
    Date August 2007
    Journal Retina (philadelphia, Pa.)
    Excerpt

    PURPOSE: The purpose of this study was to assess preference values for vein occlusions with macular edema and to determine how this may affect patient perceptions of potential treatments. METHODS: The Submacular Surgery Trials Vision Preference Value Scale and questions regarding enthusiasm for potential treatments were administered to 153 patients with vein occlusion. Univariate analyses identified predictors of preference values, followed by adjustment for potential confounders using multivariate linear regression. Relationships between preference values and enthusiasm for potential treatments were assessed. RESULTS: The mean preference values +/- SD were similar for patients with branch vein occlusions and central vein occlusions (0.65 +/- 0.20). Lower preference values were associated with duration of occlusion of >2 years (P=0.03) and poorer last-recorded visual acuity (P=0.02). Approximately one half of patients were moderately or very enthusiastic about undergoing intravitreal injection. Sixty-nine percent of branch vein occlusion patients were moderately or very enthusiastic about the standard of care, laser photocoagulation; only one third of central vein occlusion patients were moderately or very enthusiastic about standard observation. CONCLUSIONS: These data suggest that vein occlusion with macular edema has a significant impact on quality of life. Most patients were willing to undergo potentially invasive treatment.

    Title A Comparison of the Potential Acuity Meter (pam) and the Illuminated Near Card (inc) in Patients Undergoing Phacoemulsification.
    Date March 2007
    Journal Eye (london, England)
    Excerpt

    PURPOSE: To compare the accuracy of the potential acuity meter (PAM) and the illuminated near card (INC) in patients undergoing phacoemulsification. METHODS: During presurgical evaluations, both PAM and INC were tested on each study patient following dilation. Patients then rated the subjective ease of use of each test. Best spectacle-corrected visual acuity (BSCVA) was recorded at 4 and 12 weeks postoperatively. McNemar's chi(2) test for paired associations was used to analyse categorical data; paired t-tests were used for continuous variables. RESULTS: Overall, the INC was more likely than the PAM to predict BSCVA within one Snellen line (P=0.002), but this difference decreased for accuracy within two lines. The PAM predicted BSCVA within one line in 87 (70.7%) eyes, as compared to 102 (82.9%) eyes by the INC. The PAM was accurate within two lines in 109 (88.6%) eyes; the INC was accurate in 115 (93.5%) eyes. The PAM was more likely to underpredict potential acuity (P<0.001), while the INC was more likely to overpredict (P=0.004) or give exact predictions of BSCVA (P<0.001). Accuracy of the INC declined in eyes with macular comorbidity. The PAM and INC were rated as 'easy' tests by 54 (45.4%) and 93 (78.2%) patients, respectively. CONCLUSIONS: Both the PAM and the INC were useful for predicting BSCVA after phacoemulsification, but the PAM was more likely to underestimate potential acuity. The INC was easier for patients to use, and had better accuracy than the PAM in patients without macular comorbidity, but was more likely to overestimate potential acuity.

    Title Modified Laser-induced Chorioretinal Anastomosis for Treatment of Longstanding Perfused Central Retinal Vein Occlusion.
    Date October 2006
    Journal Retina (philadelphia, Pa.)
    Title The Course of Glaucoma During Pregnancy: a Retrospective Case Series.
    Date August 2006
    Journal Archives of Ophthalmology
    Excerpt

    OBJECTIVE: To better understand the course of glaucoma during pregnancy in women with preexisting disease. METHODS: Retrospective case series of 28 eyes of 15 women with glaucoma followed up during pregnancy. Data were analyzed for age, race/ethnicity, medications, glaucoma type, intraocular pressure (IOP), and visual fields before, during, and after pregnancy. RESULTS: In 16 (57.1%) of 28 eyes, IOP was stable during pregnancy, with no progression of visual field loss. In 5 eyes (17.9%), visual field loss progressed during pregnancy, while IOP remained stable or increased. In 5 eyes (17.9%), IOP increased during pregnancy, but there was no progression of visual field loss. In 2 eyes (7.1%), data were inconclusive because of medication noncompliance and preexisting severe visual field loss. Glaucoma medications were used by 13 of 15 patients to control glaucoma during pregnancy. The classes of medications used most frequently were beta-blockers, alpha2-adrenergic agents, cholinergic agents, and topical carbonic anhydrase inhibitors. CONCLUSIONS: The course of glaucoma during pregnancy is variable, and women must be monitored closely during pregnancy. Medications may be necessary to control IOP and to prevent vision loss during pregnancy.

    Title The Outcomes and Complications of 1,2-intercompartmental Supraretinacular Artery Pedicled Vascularized Bone Grafting of Scaphoid Nonunions.
    Date July 2006
    Journal The Journal of Hand Surgery
    Excerpt

    PURPOSE: Over the past decade vascularized bone grafts that use a 1,2-intercompartmental supraretinacular artery (1,2-ICSRA) pedicle have gained popularity in the treatment of scaphoid nonunions. The purpose of this study was to evaluate critically the outcome, complications, and failures of 1,2-ICSRA-based vascularized bone grafting at our institution to understand better the appropriate indications, methods, and possible contraindications. METHODS: From January 1994 through July 2003, 50 scaphoid nonunions in 49 patients were treated with 1,2-ICSRA-based vascularized bone grafts. A retrospective review of the clinical and radiographic information was performed. Two patients were lost to follow-up study. Nine female and 38 male patients averaging 24 years of age were followed-up for an average of 7.8 months. RESULTS: Thirty-four scaphoid nonunions went on to union at an average of 15.6 weeks after surgery. Complications occurred in 8 patients and consisted of graft extrusion, superficial infection, deep infection, and failure of fixation. Univariate risk factors for failure included older age, proximal pole avascular necrosis, preoperative humpback deformity, nonscrew fixation, tobacco use, and female gender. CONCLUSIONS: Although previous researchers have concluded that vascularized bone grafts based on the 1,2-ICSRA are efficacious in the treatment of scaphoid nonunions, we determined that a successful outcome is not universal and depends on careful patient and fracture selection and appropriate surgical techniques. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level IV.

    Title Bilateral Endogenous Endophthalmitis in a Patient with Hemoglobin Sc Disease.
    Date March 2006
    Journal Canadian Journal of Ophthalmology. Journal Canadien D'ophtalmologie
    Excerpt

    CASE REPORT: Bilateral endogenous endophthalmitis in the setting of pneumococcal bacteremia was diagnosed in a woman with hemoglobin SC disease who presented with decreased vision, increased redness, burning pain, and photophobia. All gram stains and cultures remained negative, and the exact source of her bacteremia was not clear. Nonetheless, early diagnosis and prompt treatment were vital to avoiding a visually devastating outcome. COMMENTS: Aggressive treatment with intravitreal and systemic antibiotics, with or without pars plana vitrectomy, was successful in restoring final visual acuity.

    Title Patellectomy After Total Knee Arthroplasty.
    Date January 2006
    Journal Clinical Orthopaedics and Related Research
    Excerpt

    We retrospectively reviewed nine patients who had condylar TKA and subsequently had a patellectomy between 1969 and 2003. One patient was lost to followup, but the remaining eight patients were followed up for an average of 49 months after patellectomy. All patellectomies were done after comminuted patellar fractures at an average of 21 months (range, 4-88 months) after the initial arthroplasty. Knee scores after the initial arthroplasty were 83 points (range, 69-97 points) and 49 points (range, 10-100 points) for pain and function, respectively. Knee scores after patellectomy were 81 (range, 20-97) and 28 (range, 0-80) for pain and function, respectively. The average range of motion before and after patellectomy was 0 degrees to 104 degrees and 2 degrees to 106 degrees , respectively. Four patients had mild extensor lags at final examination, but all were less than 10 degrees . Two patients were unable to use stairs. Two patients had complications consisting of quadriceps tendon rupture and secondary instability. Midterm results after patellectomy show knee scores for pain that are comparable to those after initial arthroplasties, but the function scores were not as good. Fifty percent of the patients had extensor lags but all were mild (< 10 degrees ). Patellectomy can provide pain relief after a patellar fracture after total knee arthroplasty but the functional results are frequently poor. LEVEL OF EVIDENCE: Therapeutic study, Level IV-1 (case series). See the Guidelines for Authors for a complete description of levels of evidence.

    Title Total Anterior Corneal Surface and Epithelial Stem Cell Harvesting: Current Microkeratomes and Beyond.
    Date December 2005
    Journal Expert Review of Medical Devices
    Excerpt

    Currently, most corneal lamellar allografts are performed by manually dissecting donor corneoscleral material for transplantation. Manual dissection is technically challenging and time intensive, and excessive handling of tissue may decrease the likelihood of obtaining viable grafts. These mechanical factors, along with problems controlling immune rejection, have prevented limbal stem cell lamellar allografts in particular from becoming more widely used. Anterior lamellar keratoplasty is gaining in clinical importance and usage but is still only practiced by a limited number of surgeons. Recently, new mechanical and femtosecond laser microkeratomes have been adapted to harvest the anterior corneal surface, including the limbal stem cell region. Preliminary results have been encouraging and give hope that this technique may prove to be of benefit to patients in the future.

    Title The Association Between Myopia and Various Subtypes of Lens Opacity: See (salisbury Eye Evaluation) Project.
    Date August 2005
    Journal Ophthalmology
    Excerpt

    PURPOSE: To establish the relationship between myopia and lens opacity. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Two thousand five hundred twenty participants from the Salisbury Eye Evaluation aged 65 to 84 years. METHODS: Participants filled out questionnaires regarding medical history, social habits, and a detailed history of distance spectacle wear. They underwent a full ocular examination. Lens photographs were taken for assessment of lens opacity using the Wilmer grading system. Multivariate logistic regression models using generalized estimating equations were used to analyze the relationship between lens opacity type and degree of myopia, while accounting for potential confounders. MAIN OUTCOME MEASURES: Presence of posterior subcapsular opacity, cortical opacity, or nuclear opacity. RESULTS: Significant associations were found between myopia and both nuclear and posterior subcapsular opacities. For nuclear opacity, the odds ratios (ORs) were 2.25 for myopia between -0.50 diopters (D) and -1.99 D (P<0.001), 3.65 for myopia between -2.00 D and -3.99 D (P<0.001), 4.54 for myopia between -4.00 D and -5.99 D (P<0.001), and 3.61 for myopia -6.00 D or more (P = 0.002). For posterior subcapsular cataracts, ORs were 1.59 for myopia between -0.50 D and -1.99 D (P = 0.11), 3.22 for myopia between -2.00 D and -3.99 D (P = 0.002), 5.36 for myopia between -4.00 D and -5.99 D (P<0.001), and 12.34 for myopia -6.00 D or more (P<0.001). No association was found between myopia and cortical opacity. The association between posterior subcapsular opacity and myopia was equally strong for those wearing glasses by age 21 years and for those without glasses; for nuclear opacity, significantly higher ORs were found for myopes who started wearing glasses after age 21. CONCLUSIONS: These results confirm the previously reported association between myopia, posterior subcapsular opacity, and nuclear opacity. Furthermore, the strong association between early spectacle wear and posterior subcapsular opacity among myopes, absent for nuclear opacity, suggests that myopia may precede opacity in the case of posterior subcapsular opacity, but not nuclear opacity. Measures of association between posterior subcapsular opacity and myopia were stronger in the current study than have previously been found. Longitudinal studies to confirm the association are warranted.

    Title Bilateral Cryptococcal Choroiditis.
    Date November 2004
    Journal Archives of Ophthalmology
    Title Occupational Risk for Nephrolithiasis and Bladder Dysfunction in a Chauffeur.
    Date November 2004
    Journal Urological Research
    Excerpt

    The occupational risks for nephrolithiasis have not been widely studied. The published literature focuses on exposure to heat stress and toxic substances, not on the equally important behavioral risk factor of limited water consumption over many years. Urologic morbidity has been associated with suppressing the need to drink or void under restrictive work environments; however, no such studies link work related behavioral change with the development of kidney stones. This case report is the first to associate a restrictive work environment with limited fluid consumption, resulting in the development of nephrolithiasis.

    Title Infections Following Laser in Situ Keratomileusis: an Integration of the Published Literature.
    Date July 2004
    Journal Survey of Ophthalmology
    Excerpt

    Infections occurring after laser in situ keratomileusis (LASIK) surgery are uncommon, but the number of reports have steadily increased in recent years. This systematic, comprehensive review and analysis of the published literature has been performed in order to develop an integrative perspective on these infections. We have stratified the data by potential associations, microbiology, treatment, and the degree of visual loss, using Fisher's exact tests and Student's t-tests for analysis. In this review, we found that Gram-positive bacteria and mycobacterium were the most common causative organisms. Type of postoperative antibiotic and steroid use was not associated with particular infecting organisms or severity of visual loss. Gram-positive infections were more likely to present less than 7 days after LASIK, and they were associated with pain, discharge, epithelial defects, and anterior chamber reactions. Fungal infections were associated with redness and tearing on presentation. Mycobacterial infections were more likely to present 10 or more days after LASIK surgery. Moderate or severe visual reductions in visual acuity occurred in 49.4% of eyes. Severe reductions in visual acuity were significantly more associated with fungal infections. Flap lift and repositioning preformed within 3 days of symptom onset may be associated with better visual outcome.

    Title Corneal Edema Resolution After "descemetorhexis".
    Date June 2004
    Journal Journal of Cataract and Refractive Surgery
    Excerpt

    A 79-year-old woman had left eye phacoemulsification complicated by inadvertent excision of Descemet's membrane (DM). One day postoperatively, the visual acuity was counting fingers with diffuse corneal edema. The patient was treated medically, with gradual resolution of the corneal edema over a 6-month period. The torn edge of DM could be visualized as the edema cleared, and no endothelial cell count could be obtained centrally. Approximately 1 year postoperatively, the central endothelial cell count was 2114 cells/mm(2) in the right eye and 827 cells/mm(2) in the left eye. The decreased cell count, increased polymegethism, and pleomorphism suggested that endothelial cells migrated to cover the stromal surface area in the absence of DM.

    Title Outcome of Phacoemulsification After Pars Plana Vitrectomy.
    Date May 2002
    Journal Ophthalmology
    Excerpt

    PURPOSE: To compare the outcome of phacoemulsification surgery in patients with and without prior vitrectomy, adjusted for confounding factors. DESIGN: Retrospective cohort study. PARTICIPANTS AND CONTROLS: Thirty-one consecutive eyes undergoing phacoemulsification after pars plana vitrectomy (PPV) and 116 consecutive eyes undergoing phacoemulsification without previous PPV. METHODS: Office records of the operating surgeons were reviewed for age, gender, type of cataract, vitrectomy status, best-corrected visual acuity (BCVA) before and after phacoemulsification, intraoperative difficulties, and postoperative complications. Bivariate analyses between these predictors and the main outcome, BCVA of 20/40 or better after phacoemulsification, were performed using Pearson's chi-square tests. An adjusted analysis of the relationship between outcome and vitrectomy status was performed with logistic regression. Pearson's chi-square tests were used to compare type of cataract, intraoperative difficulties, and postoperative complications in study and control eyes. MAIN OUTCOME MEASURES: BCVA of 20/40 or better after phacoemulsification, rates of intraoperative difficulties, and postoperative complications. RESULTS: The most common indication for PPV was macular hole. The average interval from PPV to phacoemulsification was 15.4 months. Study eyes were followed for an average of 10 months compared with 6.6 months for controls. Study eyes were more likely than controls to have predominantly nuclear sclerotic cataracts (P = 0.002). After cataract extraction, 24 of 31 study eyes (77.4%) and 110 of 116 control eyes (94.8%), had BCVAs of 20/40 or better. After adjusting for confounders, eyes without previous vitrectomy were 3.44 times more likely to obtain a BCVA of 20/40 or better than eyes with prior PPV, but this difference was not statistically significant (95% CI, 0.72-16.67). Only 3 of 31 (9.7%) study and 11 of 116 (9.4%) control eyes had intraoperative difficulties (P = 0.47). Posterior capsule plaque was the most common intraoperative difficulty in study eyes; small pupil requiring stretching or iris hooks was most common in controls. Only 1 of 31 (3.2%) study eyes had a postoperative complication other than posterior capsule opacification compared with 18 of 116 (15.5%) controls (P = 0.07). CONCLUSIONS: A large proportion of patients with prior PPV obtain good visual acuity after phacoemulsification. We did not find significantly higher rates of intraoperative difficulties or postoperative complications compared with controls. The benefits of phacoemulsification seem to be limited only by retinal comorbidity.

    Title Tetracycline-inducible System for Photoreceptor-specific Gene Expression.
    Date December 2000
    Journal Investigative Ophthalmology & Visual Science
    Excerpt

    PURPOSE: To develop a system for inducible photoreceptor-specific gene expression in transgenic mice. The tetracycline regulatory system was chosen because it possesses the useful property of direct control of gene expression through use of an exogenous agent, doxycycline, a tetracycline derivative. METHODS: Transgenic mice were generated that carried the reverse tetracycline-controlled transactivator under the control of the photoreceptor-specific promoters for rhodopsin and interphotoreceptor retinoid-binding protein. These animals were crossed with transgenic mice carrying the lacZ reporter gene under control of the tetracycline operator cassette, creating doubly transgenic mice. Doxycycline was administered to induce expression of the reporter gene. Reporter assays were then performed to evaluate lacZ expression. RESULTS: Doxycycline administration led to photoreceptor-specific expression of the lacZ reporter gene in the doubly transgenic mice. X-gal staining was restricted to photoreceptor inner segments and synaptic termini. Induction could be achieved by addition of the drug to the animals' drinking water or by intravitreal injection. Induction was noted within 24 hours of doxcycline administration. Because of variability among animals, there was an approximate correlation, but not a clean dose-response curve relating drug dose to level of reporter expression. CONCLUSIONS: A transgenic system for inducible photoreceptor-specific gene expression has been developed. This system is currently being exploited to study the effects of regulated expression of genes of biological interest.

    Title Biphasic Ocular Inflammatory Response to Endotoxin-induced Uveitis in the Mouse.
    Date April 2000
    Journal Archives of Ophthalmology
    Excerpt

    OBJECTIVE: To examine the kinetics and mechanisms of endotoxin-induced uveitis in the mouse. METHODS: C3H/HeN mice were injected subcutaneously with 0.3 mg of Salmonella typhimurium lipopolysaccharide (LPS) in 0.1 mL of phosphate-buffered saline solution or phosphate-buffered saline solution alone in 3 separate experiments; mice were killed after 1, 3, 5, and 7 days. In 2 other separate experiments, mice were killed 1, 3, 6, and 24 hours after LPS injection. All eyes were collected for histological examination, immunohistochemical analyses, aqueous protein level determination, and reverse transcriptase-polymerase chain reaction for ocular interleukin (IL)1alpha, IL-6, tumor necrosis factor alpha, and granulocyte-macrophage colony-stimulating factor messenger RNA (mRNA). Enzyme-linked immunosorbent assay was used to measure tumor necrosis factor alpha and IL-6 levels in aqueous and serum samples. RESULTS: Results were consistent for all experiments. Numbers of ocular inflammatory cells and levels of aqueous protein peaked 1 and 5 days after LPS injection. Control mice did not develop inflammation. Serum and aqueous IL-6 and ocular IL-6 mRNA levels peaked at 1 day and subsided at 3 days. However, ocular IL-1alpha, tumor necrosis factor alpha, and granulocyte-macrophage colony-stimulating factor mRNA appeared, peaked, and subsided at 3, 5, and 7 days, respectively. Predominant infiltrating cells were neutrophils at 1 day and macrophages at 5 days. Although no ocular inflammatory cells were detected before 24 hours after LPS injection, tumor necrosis factor alpha mRNA was noticed at 1 hour, peaked at 3 hours, and disappeared at 6 hours and granulocyte-macrophage colony-stimulating factor mRNA was spotted only at 3 hours after LPS injection. CONCLUSIONS: The ocular inflammatory response to C3H/ HeN mouse endotoxin-induced uveitis is biphasic for 7 days. The first wave appears at day 1 and subsides by day 3. A second, higher peak appears at day 5. The 2 inflammatory waves are related to the kinetics of the different cytokines released in the eye. This is in contrast to the rat monophasic endotoxin-induced uveitis model, which has only one peak of intense inflammation associated with cytokine release. CLINICAL RELEVANCE: A biphasic inflammatory response associated with cytokine release lasting several days is observed in C3H/HeN mice with endotoxin-induced uveitis. Because human anterior uveitis has a tendency to be recurrent in nature, this might be a better experimental model.

    Title Transcriptional Regulation of Cellular Retinaldehyde-binding Protein in the Retinal Pigment Epithelium. A Role for the Photoreceptor Consensus Element.
    Date April 1998
    Journal The Journal of Biological Chemistry
    Excerpt

    Cellular retinaldehyde-binding protein (CRALBP) is abundantly expressed in the retinal pigment epithelium (RPE) and Muller cells of the retina, where it is thought to function in retinoid metabolism and visual pigment regeneration. Mutations in human CRALBP that destroy retinoid binding have been linked to autosomal recessive retinitis pigmentosa. To identify the DNA elements that regulate expression of the human CRALBP gene in the RPE, transient transfection studies were carried out with three CRALBP-expressing human RPE cell culture systems. The regions from -2089 to -1539 base pairs and from -243 to +80 base pairs demonstrated positive regulatory activity. Similar activity was not observed with cultured human breast, liver, or skin cells. Since sequence analysis of the -243 to +80 region identified the presence of two photoreceptor consensus element-1 (PCE-1) sites, elements that have been implicated in photoreceptor gene regulation, the role of these sequences in RPE expression was examined. Mutation of either PCE-1 site significantly reduced reporter activity, and mutation or deletion of both sites dramatically reduced activity. Electrophoretic mobility shift analysis with RPE nuclear extracts revealed two complexes that required intact PCE-1 sites. These studies also identified two identical sequences (GCAGGA) flanking PCE-1, termed the binding CRALBP element (BCE), that are also important for complex formation. Southwestern analysis with PCE-1/BCEcontaining probes identified species with apparent masses near 90-100 and 31 kDa. These results begin to identify the regulatory regions required for RPE expression of CRALBP and suggest that PCE-1-binding factor(s) may play a role in regulating RPE as well as photoreceptor gene expression.

    Title Pulse Oximetry and Peak Flow As Indicators of Wheezing Severity in Children and Improvement Following Bronchodilator Treatments.
    Date November 1992
    Journal The American Journal of Emergency Medicine
    Excerpt

    This study examined the changes from the initial peak flows and oxygen saturations (OSAT) of wheezing children at presentation to the emergency department through their treatment in the emergency department. Data was collected prospectively on 785 patients 5 to 20 years of age during an 11-month period from November 1, 1990, to September 30, 1991. Both the initial OSAT and peak flows were correlated with the number of bronchodilator treatments required in the emergency department and with the need for hospitalization. Both the initial OSAT and the peak flows had a limited ability to predict the need for hospitalization. Oxygen saturation appears to be a valid measure of wheezing severity and is more easily obtained in children of all ages. Following bronchodilator treatment, peak flow results in a larger quantitative improvement than OSAT; however, this difference does not appear to have any significant advantage. Aerosolized albuterol and subcutaneous epinephrine resulted in a similar degree of improvement as measured by peak flow and by oxygen saturation, with clinically similar changes in heart rate.

    Title Correlation Between Abo Blood Type and Golgi P-glycoprotein Expression in Epithelia.
    Date August 1990
    Journal Lancet
    Title Surgical Goniosynechialysis for Angle-closure Glaucoma.
    Date June 1990
    Journal Ophthalmology
    Excerpt

    Fifteen patients with synechial angle-closure glaucoma uncontrolled by medical and laser therapy were treated with surgical goniosynechialysis. Five patients were treated with goniosynechialysis alone, and ten were treated with goniosynechialysis in combination with other surgical procedures. The procedure was successful, in terms of reducing synechiae, in 14 eyes (93%). The extent of angle closure was reduced from 340 degrees +/- 45 degrees (mean +/- standard deviation) preoperatively to 80 degrees +/- 70 degrees postoperatively; the mean reduction was 260 degrees +/- 95 degrees (P less than 0.0001) for the group overall and 280 degrees +/- 80 degrees (P less than 0.0007) for the subgroup treated with goniosynechialysis alone. The mean preoperative intraocular pressure (IOP) was 40 +/- 4 mmHg. The mean postoperative IOP was 14 +/- 4 mmHg. The mean reduction in IOP was 26 +/- 15 mmHg (P less than 0.0001) for the group overall and 27 +/- 18 mmHg (P less than 0.015) for the subgroup treated with goniosynechialysis alone. Glaucoma medications were reduced from a mean of 2.6 +/- 1.0 preoperatively to 1.1 +/- 1.2 postoperatively for the group overall and to 1.4 +/- 1.5 for the subgroup treated with goniosynechialysis alone. Complications consisted of two eyes with intraoperative bleeding. One of these required intraoperative conversion to surgical trabeculectomy. The other was associated with a transient postoperative IOP elevation to 40 mmHg. Surgical goniosynechialysis may be an effective means of reducing synechiae and lowering IOP, either alone or in conjunction with other surgical procedures, in patients with angle closures of less than 6 months' duration.

    Title The Amsler Grid.
    Date March 1988
    Journal Retina (philadelphia, Pa.)
    Title Ocular Abnormalities Associated with Cutaneous Melanoma and Vitiligolike Leukoderma.
    Date February 1987
    Journal Graefe's Archive for Clinical and Experimental Ophthalmology = Albrecht Von Graefes Archiv Für Klinische Und Experimentelle Ophthalmologie
    Excerpt

    Several varieties of ocular pathology are associated with acquired cutaneous hypomelanosis (leukoderma; vitiligo). Our current study was undertaken to investigate the relationship between ophthalmologic disorders and a specific depigmentary phenomenon, the vitiligolike leukoderma of cutaneous melanoma. Over the past 14 years, eight patients with cutaneous melanoma and widespread areas of hypopigmentation were identified at the Pigmented Lesion Clinic of the Massachusetts General Hospital. The seven patients who underwent ophthalmologic examination had pigment-related ocular abnormalities. Among these were inflammations of the uveal tract in three patients, heterochromia in two, halo nevi of the choroid in one, and hypopigmentation and/or atrophy of the retinal pigment epithelium or choroid in four. Our findings demonstrate that ocular disease may be a component in a syndrome consisting also of cutaneous melanoma and vitiligolike leukoderma and suggest the need for complete ophthalmologic examinations in patients with melanoma and leukoderma.

    Title The Dysplastic Nevus Syndrome. A Pedigree with Primary Malignant Melanomas of the Choroid and Skin.
    Date February 1986
    Journal Ophthalmology
    Excerpt

    Intraocular and cutaneous melanomas developed in a family with features of the dysplastic nevus syndrome. (The proband had a choroidal melanoma, his son had a cutaneous melanoma, and his grandchildren have mildly atypical melanocytic lesions clinically.) The syndrome is characterized by clinically and histologically atypical nevi, which may serve as cutaneous markers to identify persons at high risk for melanomas, both of the skin and the eye. Although it has been proposed recently that the association of intraocular melanoma with cutaneous melanoma and the dysplastic nevus syndrome may be coincidental, statistical analysis suggests that the occurrence of the two forms of melanoma in the same patient and in different members of the same family is not explained by chance alone. Therefore, until the relationship between intraocular and cutaneous melanomas is more fully elucidated, recognition of the dysplastic nevus syndrome is important, and the skin of patients suspected of having intraocular melanomas should be examined routinely for evidence of atypical melanocytic lesions.

    Title Sample Size Graphs for "proving the Null Hypothesis".
    Date September 1984
    Journal Controlled Clinical Trials
    Excerpt

    Sample size graphs are given for clinical trials designed to test whether an experimental therapy is as effective as a standard therapy. We assume a dichotomous outcome variable and a one-sided test of the hypothesis that the probability of success with standard therapy is greater than the probability of success with experimental therapy by at least some specified amount delta. Graphs are given for significance level alpha = 0.01, 0.025, 0.05; type II error beta = 0.10, 0.20; and delta = 0.10, 0.20.

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