About

Bobby S. Korn is a Professor of Clinical Ophthalmology at UC San Diego School of Medicine. His research focuses on various aspects of ophthalmology, including thyroid eye disease, orbital inflammation, eyelid reconstruction, and strabismus. He has contributed to numerous studies examining the systemic effects of treatments such as teprotumumab on thyroid function and eyelid retraction, as well as surgical outcomes for eyelid and orbital conditions. His work involves both clinical trials and retrospective analyses, aiming to improve understanding and management of complex ophthalmic disorders.

Research topics

• Surgery
• Medicine
• Internal medicine
• Immunology
• Dermatology
• Pathology
• Ophthalmology

Selected publications

• Use of Electronic Health Records to Examine Margin-to-Reflex Distance in Normal Patients

  Research Square · 2026-02-27

  preprintOpen access
  PublisherOA PDFDOI

• Outcomes of Frontalis Advancement With or Without External Levator Advancement for Congenital Ptosis: A Retrospective Comparative Study

  American Journal of Ophthalmology · 2025-09-23 · 1 citations

  articleSenior author
  PublisherDOI

• Intersurgeon Variability in Proptosis Reduction After Orbital Decompression for Thyroid Eye Disease: A Multicenter Analysis

  Ophthalmic Plastic and Reconstructive Surgery · 2025-10-13

  articleCorresponding

  PURPOSE: This study assesses intersurgeon variability in proptosis reduction after orbital decompression for thyroid eye disease. METHODS: This multicenter retrospective study included patients with thyroid eye disease who underwent orbital decompression from 1 of 7 surgeons at 7 different institutions between January 2002 and December 2018. Data were included if a single decompression technique was performed on ≥10 patients by ≥2 surgeons. The primary outcome was postoperative change in proptosis with emphasis on comparison among surgeons utilizing similar surgical techniques. Statistical analysis was performed with χ 2 and ANOVA testing, and a multivariable logistic regression model was generated. RESULTS: Six hundred thirty-three orbits that underwent orbital decompression were included. Five different decompression techniques were analyzed: medial wall (n = 29), fat + lateral wall (n = 113), medial wall + floor (n = 123), fat + lateral wall + medial wall (n = 140), and fat + lateral wall + medial wall + floor (n = 228), without significant difference in proptosis reduction among surgeons. Surgeons did not demonstrate significant differences in outcomes at different time points compared with each other or themselves. Outcomes when comparing endoscopic versus open medial wall decompression varied among surgery types. Multivariate modeling revealed a statistically significant association between postoperative change in proptosis with preoperative proptosis ( p < 0.001). CONCLUSIONS: Postoperative change in proptosis did not differ significantly between surgeons utilizing similar orbital decompression techniques for patients with thyroid eye disease. This study may strengthen the statistical validity of multicenter clinical trials assessing orbital decompression outcomes performed by surgeons employing uniform surgical techniques, thereby advancing our understanding of optimal surgical management strategies for thyroid eye disease.

  PublisherDOI

• Effects of Teprotumumab on Eyelid Retraction in Thyroid Eye Disease

  Ophthalmic Plastic and Reconstructive Surgery · 2024-05-09 · 6 citations

  articleCorresponding

  PURPOSE: This study evaluates the efficacy of teprotumumab in reducing eyelid retraction in thyroid eye disease (TED) patients. METHODS: This retrospective study included patients with active or chronic moderate-to-severe TED who completed at least 4 cycles of teprotumumab. Patients with upper and/or lower eyelid retraction, defined as margin-to-reflex distance (MRD) 1 and/or MRD2 of more than 5 mm, in one or OU were included. The main outcome measure was a change in MRD1 and MRD2 after treatment. Changes in MRD1 and MRD2 were each analyzed for correlation (r) with changes in exophthalmolmetry. Student t test was performed for each comparison, and p values <0.05 were considered significant. RESULTS: The study included 91 patients, predominantly female (87%), with an average age of 52.02 ± 14.6 years. The mean baseline proptosis measurement was 21.8 ± 2.9 OD and 21.7 ± 3.3 OS. The average MRD1 was 5.5 ± 1.5 OD and 5.4 ± 1.7 OS, and the average MRD2 was 6.1 ± 1.1 OD and 6.2 ± 1.1 OS. The follow-up duration post-treatment was 37.5 ± 31.7 weeks. At first follow-up post-treatment, the mean change in proptosis, MRD1, and MRD2 were -2.6 ± 2.0 OD, -2.5 ± 2.1 OS, -0.8.5 ± 1.4 OD, -0.8 ± 1.0 OS, and -0.7 ± 0.9 OD, -0.8 ± 1.0 OS, respectively. Correlation analysis showed that proptosis reduction was positively correlated with MRD1 and MRD2 reduction at the first post-treatment follow-up (MRD1: r = 0.23, p value < 0.01; MRD2: r = 0.17, p = 0.03]. CONCLUSION: Teprotumumab treatment improves upper and lower eyelid retraction. The improvement in MRD correlated positively with proptosis reduction, indicating the influence of globe position on eyelid position.

  PublisherDOI

• Orbital decompression following treatment with teprotumumab for thyroid eye disease

  Canadian Journal of Ophthalmology · 2024-07-24 · 6 citations

  articleOpen access

  OBJECTIVE: To quantify the observed decrease in orbital decompressions being performed at one tertiary care institution and to determine the rate and predictive factors of orbital decompression surgery following treatment with teprotumumab for thyroid eye disease. METHODS: Epic's SlicerDicer program was used to analyze recent trends in the overall number of thyroid eye disease (TED) patients evaluated in the oculoplastic surgery department, as well as usage trends of CPT codes 67445 (lateral orbitotomy with bone removal for decompression) and 67414 (orbitotomy with removal of bone for decompression). A retrospective chart review of active moderate-to-severe TED patients treated with teprotumumab was performed at a single tertiary care center. The main outcome measure was whether or not patients underwent bony orbital decompression surgery following treatment with teprotumumab. The SlicerDicer search demonstrated stable usage of CPT codes 67445 and 67414 from 2016 to 2019, followed by a significant decrease from 2020 to 2023, over a background of increasing numbers of TED patients evaluated in clinic. Following teprotumumab therapy, 25% of patients and 18% of orbits underwent bony decompression. Surgically decompressed patients had higher pre- and post-teprotumumab exophthalmometry measurements compared with patients who did not undergo bony decompression. Average time to decompression following conclusion or cessation of teprotumumab therapy was 12.6 months. CONCLUSION: While the number of TED patients treated at one tertiary care center has risen over recent years, the number of orbital decompression surgeries has declined. Orbital decompression, however, is still needed in select patients after treatment with teprotumumab.

  PublisherOA PDFDOI

• Is Blepharoplasty Cost-effective? Utility Analysis of Dermatochalasis and Cost-effectiveness Analysis of Upper Eyelid Blepharoplasty

  Ophthalmic Plastic and Reconstructive Surgery · 2024-03-21

  article

  PURPOSE: This cross-sectional prospective study measured utility values of upper eyelid dermatochalasis to quantify its impact on quality of life and assess cost-effectiveness of upper blepharoplasty. METHODS: Utility of dermatochalasis was assessed using the standard reference gamble and time trade-off methods, with dual anchor points of perfect eye function and perfect health. The utility value obtained was used to create a Markov model and run a cost-effectiveness analysis of blepharoplasty as a treatment for dermatochalasis while utilizing the societal perspective. RESULTS: One hundred three patients with dermatochalasis recruited from an urban outpatient ophthalmology clinic completed the utility survey. The authors determined utility values for dermatochalasis ranging from 0.74 to 0.92 depending on the measurement method (standard reference gamble/time trade-off) and anchor points. The cost-effectiveness analysis yielded an incremental cost-effectiveness ratio of $3,146 per quality-adjusted life year, well under the conventional willingness-to-pay threshold of $50,000 per quality-adjusted life year. Probabilistic sensitivity analysis with Monte Carlo simulation demonstrated that blepharoplasty would be cost-effective in 88.1% of cases at this willingness-to-pay threshold. CONCLUSIONS: Dermatochalasis has an impact on quality of life that is significantly associated with level of perceived functional impairment. Rising health care costs have underscored the importance of providing value-based treatment to patients, and the results of this study suggest that blepharoplasty is a cost-effective treatment option for symptomatic bilateral upper eyelid dermatochalasis.

  PublisherDOI

• Evaluating the Accuracy of ChatGPT and Google BARD in Fielding Oculoplastic Patient Queries: A Comparative Study on Artificial versus Human Intelligence

  Ophthalmic Plastic and Reconstructive Surgery · 2024-01-12 · 39 citations

  articleSenior authorCorresponding

  PURPOSE: This study evaluates and compares the accuracy of responses from 2 artificial intelligence platforms to patients' oculoplastics-related questions. METHODS: Questions directed toward oculoplastic surgeons were collected, rephrased, and input independently into ChatGPT-3.5 and BARD chatbots, using the prompt: "As an oculoplastic surgeon, how can I respond to my patient's question?." Responses were independently evaluated by 4 experienced oculoplastic specialists as comprehensive, correct but inadequate, mixed correct and incorrect/outdated data, and completely incorrect. Additionally, the empathy level, length, and automated readability index of the responses were assessed. RESULTS: A total of 112 patient questions underwent evaluation. The rates of comprehensive, correct but inadequate, mixed, and completely incorrect answers for ChatGPT were 71.4%, 12.9%, 10.5%, and 5.1%, respectively, compared with 53.1%, 18.3%, 18.1%, and 10.5%, respectively, for BARD. ChatGPT showed more empathy (48.9%) than BARD (13.2%). All graders found that ChatGPT outperformed BARD in question categories of postoperative healing, medical eye conditions, and medications. Categorizing questions by anatomy, ChatGPT excelled in answering lacrimal questions (83.8%), while BARD performed best in the eyelid group (60.4%). ChatGPT's answers were longer and potentially more challenging to comprehend than BARD's. CONCLUSION: This study emphasizes the promising role of artificial intelligence-powered chatbots in oculoplastic patient education and support. With continued development, these chatbots may potentially assist physicians and offer patients accurate information, ultimately contributing to improved patient care while alleviating surgeon burnout. However, it is crucial to highlight that artificial intelligence may be good at answering questions, but physician oversight remains essential to ensure the highest standard of care and address complex medical cases.

  PublisherDOI

• Teprotumumab for Thyroid Eye Disease-related Strabismus

  Ophthalmic Plastic and Reconstructive Surgery · 2024-02-02 · 12 citations

  articleOpen access

  PURPOSE: To assess and quantify teprotumumab's effect on thyroid eye disease-related strabismus by change in measured horizontal and vertical deviations and change in extraocular motility. METHODS: We reviewed a series of patients with thyroid eye disease-related strabismus treated with teprotumumab. Exclusion criteria included age under 18 years, strabismus of alternate etiology, or thyroid eye disease-related reconstructive surgery during the treatment course. Primary outcomes were absolute (prism diopters) and relative (%) differences in horizontal and vertical deviations in primary position at distance, as well as change in ductions of the more affected eye. Secondary outcomes included incidence and timing of strabismus surgery postteprotumumab. RESULTS: Thirty-one patients were included, with mean age 63 years and thyroid eye disease duration 10 months. After teprotumumab, there was 6 prism diopters (39%) mean reduction in vertical deviation ( p < 0.001), without significant change in mean horizontal deviation ( p = 0.75). Supraduction, abduction, adduction, and infraduction significantly improved in the more restricted eye ( p < 0.01, p < 0.01, p = 0.04, and p = 0.01, respectively). Thirty-five percent of patients underwent strabismus surgery posttreatment, at an average 10 months after last infusion. CONCLUSIONS: Teprotumumab produced a statistically significant reduction in vertical but not horizontal strabismus angles in primary position at distance. Extraocular motility in all 4 ductions also improved. A substantial minority of patients still required strabismus surgery following teprotumumab.

  PublisherOA PDFDOI

• The influence of orbital architecture on strabismus in craniosynostosis

  Journal of American Association for Pediatric Ophthalmology and Strabismus · 2024-01-13 · 4 citations

  articleOpen access

  PURPOSE: To better characterize the correlation of bony orbital dysmorphology with strabismus in craniosynostosis. METHODS: The medical records of patients with craniosynostosis with and without strabismus seen at Rady Children's Hospital (San Diego, CA) from March 2020 to January 2022 were reviewed retrospectively in this masked, case-control study. Computed tomography scans of the orbits were analyzed to obtain dimensions of the orbital entrance and orbital cone. Primary outcome was correlation of strabismus with orbital measurements. RESULTS: A total of 30 orbits from 15 patients with strabismus and 15 controls were included. Craniofacial disorders included in the study were nonsyndromic craniosynostosis (63%), Crouzon syndrome (13%), Apert syndrome (13%), and Pfeiffer syndrome (10%). Orbital index (height:width ratio) (P = 0.01) and medial orbital wall angle (P = 0.04) were found to differ significantly between the strabismus and control groups. CONCLUSIONS: In our small cohort, bony orbital dimensions, including the ratio of orbital height to width and bowing of the medial orbital wall, were associated with strabismus in craniosynostosis.

  PublisherOA PDFDOI

• What Systemic Medical therapy Is Available for Treatment of Cutaneous Malignancies?

  2024-05-30

  book-chapter1st authorCorresponding

  Summary Surgical resection remains the standard of care for periocular BCC and SCC whenever margins can be obtained in patients fit for surgery. However, in the setting of unresectable lesions, metastatic lesions, or lesions whose resection would result in loss of vital structures such as the globe or the facial nerve, systemic small molecule therapies may be considered as new and potentially promising options, whether as neoadjuvant therapy, adjuvant therapy, monotherapy, or in combination with other nonsurgical treatments.

  PublisherDOI

Frequent coauthors

• Don O. Kikkawa

  University of California, San Diego

  306 shared

• Catherine Y. Liu

  University of California, San Diego

  117 shared

• Michelle Ting

  Fleet Science Center

  52 shared

• Jonathan H. Lin

  VA Palo Alto Health Care System

  40 shared

• Audrey C. Ko

  University of California, San Diego

  39 shared

• Lilangi S. Ediriwickrema

  University of California, Irvine

  35 shared

• Nicole J. Topilow

  Fleet Science Center

  33 shared

• Ramzi M. Alameddine

  American University of Beirut

  28 shared

Education

• M.D., Ophthalmology

  University of California, San Diego

  1991

• B.S., Biology

  University of California, San Diego

  1987