Performance of Google's Artificial Intelligence Chatbot "Bard" (Now "Gemini") on Ophthalmology Board Exam Practice Questions.

PURPOSE: To assess the performance of "Bard," one of ChatGPT's competitors, in answering practice questions for the ophthalmology board certification exam. METHODS: In December 2023, 250 multiple-choice questions from the "BoardVitals" ophthalmology exam question bank were randomly selected and entered into Bard to assess the artificial intelligence chatbot's ability to comprehend, process, and answer complex scientific and clinical ophthalmic questions. A random mix of text-only and image-and-text questions were selected from 10 subsections. Each subsection included 25 questions. The percentage of correct responses was calculated per section, and an overall assessment score was determined. RESULTS: On average, Bard answered 62.4% (156/250) of questions correctly. The worst performance was 24% (6/25) on the topic of "Retina and Vitreous," and the best performance was on "Oculoplastics," with a score of 84% (21/25). While the majority of questions were entered with minimal difficulty, not all questions could be processed by Bard. This was particularly an issue for questions that included human images and multiple visual files. Some vignette-style questions were also not understood by Bard and were therefore omitted. Future investigations will focus on having more questions per subsection to increase available data points. CONCLUSIONS: While Bard answered the majority of questions correctly and is capable of analyzing vast amounts of medical data, it ultimately lacks the holistic understanding and experience-informed knowledge of an ophthalmologist. An ophthalmologist's ability to synthesize diverse pieces of information and draw from clinical experience to answer complex standardized board questions is at present irreplaceable, and artificial intelligence, in its current form, can be employed as a valuable tool for supplementing clinicians' study methods.

Out-of-pocket expenses associated with pediatric heart transplantation.

INTRODUCTION: Heart transplantation in children is associated with high resource utilization. However, the financial burden on families and the association with patient and demographic factors remains unclear. This study aims to examine out-of-pocket expenses associated with pediatric heart transplantation. METHODS: An anonymous REDCap survey was distributed to caregivers of children who have undergone heart transplantation using social media, national organizations, and during clinic encounters from May through August 2022. RESULTS: There were a total of 146 respondents. The median monthly out-of-pocket expense was $250 (IQR $75-$500) and 20 respondents (13.7%) reported monthly expenses of >$1000. Families with commercial insurance reported significantly higher out-of-pocket expenses compared to those with government-sponsored insurance (median $350 vs. $100, p < .001). Families with government-sponsored insurance were most happy with their insurance coverage, followed by commercial insurance and then coverage through the Affordable Care Act (p < .001 for all pairwise comparisons). There was no statistically significant difference in overall transplant-related out-of-pocket expenses based on total household income (p = .222). Monthly out-of-pocket expense was not associated with the number of medications, type of immunosuppressants, or post-transplant complications including rejection, PTLD, or CAV (p = NS for all). Cardiac catheterizations and unplanned admissions were reported as the events that incurred the highest out-of-pocket expense. CONCLUSION: Families of children who have undergone heart transplantation can incur significant out-of-pocket expenses and strategies to mitigate this financial burden should be investigated.

Rates of respiratory syncytial virus (RSV)-associated hospitalization among adults with congestive heart failure-United States, 2015-2017.

BACKGROUND: Respiratory syncytial virus (RSV) can cause severe disease in adults with cardiopulmonary conditions, such as congestive heart failure (CHF). We quantified the rate of RSV-associated hospitalization in adults by CHF status using population-based surveillance in the United States. METHODS: Population-based surveillance for RSV (RSV-NET) was performed in 35 counties in seven sites during two respiratory seasons (2015-2017) from October 1-April 30. Adults (≥18 years) admitted to a hospital within the surveillance catchment area with laboratory-confirmed RSV identified by clinician-directed testing were included. Presence of underlying CHF was determined by medical chart abstraction. We calculated overall and age-stratified (<65 years and ≥65 years) RSV-associated hospitalization rates by CHF status. Estimates were adjusted for age and the under-detection of RSV. We also report rate differences (RD) and rate ratios (RR) by comparing the rates for those with and without CHF. RESULTS: 2042 hospitalized RSV cases with CHF status recorded were identified. Most (60.2%, n = 1230) were ≥65 years, and 28.3% (n = 577) had CHF. The adjusted RSV hospitalization rate was 26.7 (95% CI: 22.2, 31.8) per 10,000 population in adults with CHF versus 3.3 (95% CI: 3.3, 3.3) per 10,000 in adults without CHF (RR: 8.1, 95% CI: 6.8, 9.7; RD: 23.4, 95% CI: 18.9, 28.5). Adults with CHF had higher rates of RSV-associated hospitalization in both age groups (<65 years and ≥65 years). Adults ≥65 years with CHF had the highest rate (40.5 per 10,000 population, 95% CI: 35.1, 46.6). CONCLUSIONS: Adults with CHF had 8 times the rate of RSV-associated hospitalization compared with adults without CHF. Identifying high-risk populations for RSV infection can inform future RSV vaccination policies and recommendations.

Estimated Burden of Community-Onset Respiratory Syncytial Virus-Associated Hospitalizations Among Children Aged <2 Years in the United States, 2014-15.

BACKGROUND: Respiratory syncytial virus (RSV) is a major cause of hospitalizations in young children. We estimated the burden of community-onset RSV-associated hospitalizations among US children aged <2 years by extrapolating rates of RSV-confirmed hospitalizations in 4 surveillance states and using probabilistic multipliers to adjust for ascertainment biases. METHODS: From October 2014 through April 2015, clinician-ordered RSV tests identified laboratory-confirmed RSV hospitalizations among children aged <2 years at 4 influenza hospitalization surveillance network sites. Surveillance populations were used to estimate age-specific rates of RSV-associated hospitalization, after adjusting for detection probabilities. We extrapolated these rates using US census data. RESULTS: We identified 1554 RSV-associated hospitalizations in children aged <2 years. Of these, 27% were admitted to an intensive care unit, 6% needed mechanical ventilation, and 5 died. Most cases (1047/1554; 67%) had no underlying condition. Adjusted age-specific RSV hospitalization rates per 100 000 population were 1970 (95% confidence interval [CI],1787 to 2177), 897 (95% CI, 761 to 1073), 531 (95% CI, 459 to 624), and 358 (95% CI, 317 to 405) for ages 0-2, 3-5, 6-11, and 12-23 months, respectively. Extrapolating to the US population, an estimated 49 509-59 867 community-onset RSV-associated hospitalizations among children aged <2 years occurred during the 2014-2015 season. CONCLUSIONS: Our findings highlight the importance of RSV as a cause of hospitalization, especially among children aged <2 months. Our approach to estimating RSV-related hospitalizations could be used to provide a US baseline for assessing the impact of future interventions.

Short-Term Incidence of Sequelae of HCV Infection Among Medicaid Beneficiaries in Oregon.

OBJECTIVES: Given the known high morbidity and mortality of hepatitis C virus (HCV) infection in Oregon, we sought to develop a practical method of estimating the severe sequelae of HCV infection among Medicaid beneficiaries in Oregon. METHODS: We assembled a retrospective cohort that identified all Oregon Medicaid beneficiaries with HCV infection enrolled for at least 1 year during 2009-2013. We linked this cohort to 3 data sets to identify HCV-related deaths, cases of hepatocellular carcinoma (HCC), and first hospitalizations for advanced liver disease (ALD). We calculated incidence density rates and used multivariable Cox regression modeling to calculate adjusted hazard ratios (aHRs) to evaluate the association between demographic characteristics (birth year, sex, race, ethnicity) and these 3 outcomes. RESULTS: Of 11 790 Oregon Medicaid beneficiaries with HCV infection, 474 (4.0%) had an HCV-related death, 156 (1.3%) had HCC, and 596 (5.1%) had a first hospitalization for ALD. Adjusted hazard ratios for deaths were 2.2 (95% confidence interval [CI], 1.6-2.8) among persons born in 1945 through 1965 (vs persons born after 1965), 2.1 (95% CI, 1.7-2.5) among males (vs females), and 1.9 (95% CI, 1.2-2.9) among Asian/Pacific Islanders and 2.2 (95% CI, 1.5-3.2) among American Indian/Alaska Natives (vs white persons). The same risk groups had significant aHRs for first hospitalizations for ALD. Persons born before 1945 (aHR = 17.0; 95% CI, 5.2-55.8) and in 1945 through 1965 (aHR = 12.8; 95% CI, 4.1-40.3) vs born after 1965, males (aHR = 3.3; 95% CI, 2.3-4.8) vs females, and Asian/Pacific Islanders (aHR = 3.9; 95% CI, 2.3-6.7) vs white persons had higher risks for HCC. CONCLUSIONS: Continued assessments using the methods piloted in this study will allow Oregon to monitor trends in severe sequelae of HCV infection over time.

POSTOPERATIVE HEMORRHAGIC OCCLUSIVE RETINAL VASCULITIS: A FORME FRUSTE VARIANT?

PURPOSE: To present a forme fruste variant of hemorrhagic occlusive retinal vasculitis (HORV) after uncomplicated cataract surgery performed with vancomycin in the irrigating solution. METHODS: A report of a single patient who developed HORV; the clinical features and course are described and compared with previously reported cases. RESULTS: Ultra-widefield fluorescein angiography demonstrated an occlusive vasculitis in both eyes 1 week after uncomplicated cataract surgery in which vancomycin was added to the irrigating solution. An extensive systemic evaluation including a hypercoagulable workup, serum electrophoresis, complete blood count, and carotid and cardiac ultrasound was negative. Visual acuity was unaffected, and the patient remained 20/20 in each eye one year after surgery without treatment. This is a markedly different outcome than seen in previously reported cases of HORV. CONCLUSION: Ultra-widefield angiography was helpful to confirming the diagnosis of HORV in this milder case example in a patient who maintained excellent vision. This forme fruste variant of HORV after exposure to vancomycin suggests that the incidence of HORV after cataract surgery may be more common than previously reported. Vigilance, close observation, and broad reporting can help further clarify the incidence and potential adverse effects of routinely using intracameral vancomycin during cataract surgery.

ATYPICAL MACULOPATHY IN A PATIENT WITH LIGHT CHAIN DEPOSITION DISEASE MIMICKING ADVANCED GEOGRAPHIC ATROPHY.

PURPOSE: To report a previously unreported presentation of advanced geographic atrophy of the macula mimicking nonneovascular (dry) age-related macular degeneration in a patient with light chain deposition disease. METHODS: Ocular examination included dilated fundus examination, fundus autofluorescence, full-field electroretinography, and spectral domain optical coherence tomography. PATIENTS: Single-patient case report. RESULTS: Dilated fundus examination demonstrated diffuse loss of the retinal pigment epithelium in a geographic atrophy pattern in the macula and drusenlike deposits localized to the outer retina and retinal pigment epithelium. There were no signs of choroidal neovascularization or retinal pigment epithelium detachments. Fundus autofluorescence demonstrated wide areas of retinal pigment epithelium loss. Full-field electroretinography was normal. Spectral domain optical coherence tomography displayed atrophy of the outer retinal layers. DISCUSSION: This is the first documented case of drusenlike deposits and maculopathy in a patient with light chain deposition disease that mimics advanced geographic atrophy that is typically observed in nonneovascular age-related macular degeneration. Physicians should be aware of the macular changes that can be associated with light chain deposition disease, and patients with light chain deposition disease should be regularly evaluated for associated macular disease.

DETECTION OF MICROVASCULAR CHANGES IN EYES OF PATIENTS WITH DIABETES BUT NOT CLINICAL DIABETIC RETINOPATHY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

PURPOSE: To evaluate the ability of optical coherence tomography angiography to detect early microvascular changes in eyes of diabetic individuals without clinical retinopathy. METHODS: Prospective observational study of 61 eyes of 39 patients with diabetes mellitus and 28 control eyes of 22 age-matched healthy subjects that received imaging using optical coherence tomography angiography between August 2014 and March 2015. Eyes with concomitant retinal, optic nerve, and vitreoretinal interface diseases and/or poor-quality images were excluded. Foveal avascular zone size and irregularity, vessel beading and tortuosity, capillary nonperfusion, and microaneurysm were evaluated. RESULTS: Foveal avascular zone size measured 0.348 mm² (0.1085-0.671) in diabetic eyes and 0.288 mm² (0.07-0.434) in control eyes (P = 0.04). Foveal avascular zone remodeling was seen more often in diabetic than control eyes (36% and 11%, respectively; P = 0.01). Capillary nonperfusion was noted in 21% of diabetic eyes and 4% of control eyes (P = 0.03). Microaneurysms and venous beading were noted in less than 10% of both diabetic and control eyes. Both diabetic and healthy control eyes demonstrated tortuous vessels in 21% and 25% of eyes, respectively. CONCLUSION: Optical coherence tomography angiography was able to image foveal microvascular changes that were not detected by clinical examination in diabetic eyes. Changes to the foveal avascular zone and capillary nonperfusion were more prevalent in diabetic eyes, whereas vessel tortuosity was observed with a similar frequency in normal and diabetic eyes. Optical coherence tomography angiography may be able to detect diabetic eyes at risk of developing retinopathy and to screen for diabetes quickly and noninvasively before the systemic diagnosis is made.

The Association Between Medicaid Coverage for Children and Parents Persists: 2002-2010.

To assess the association between a child's and their parent's public health insurance status during a time when children had access to coverage independent of policies that impacted adults' access. Secondary data from the Oregon Health Plan (OHP) [Oregon's Medicaid and Children's Health Insurance Programs] for families with at least one parent and one child with OHP coverage at any time during the study period (2002-2010). We linked children to their parents in the OHP data set and examined longitudinal associations between the coverage patterns for children and their parents, controlling for several demographic and economic confounders. We tested for differences in the strength of associations in monthly coverage status in five time periods throughout the nine-year study period. The odds of a child being insured by the OHP in months in which at least one parent had OHP coverage were significantly higher than among children whose parents were not enrolled at that time. Children with at least one parent who maintained or gained OHP coverage in a given month had a much higher probability of being enrolled in the OHP in that month, compared to children who had no covered parents in the given month or the month prior. Despite implementation of policies that differentially affected eligibility requirements for children and adults, strong associations persisted between coverage continuity for parents and children enrolled in Oregon public health insurance programs.

Effect of expanding medicaid for parents on children's health insurance coverage: lessons from the Oregon experiment.

IMPORTANCE: In the United States, health insurance is not universal. Observational studies show an association between uninsured parents and children. This association persisted even after expansions in child-only public health insurance. Oregon's randomized Medicaid expansion for adults, known as the Oregon Experiment, created a rare opportunity to assess causality between parent and child coverage. OBJECTIVE: To estimate the effect on a child's health insurance coverage status when (1) a parent randomly gains access to health insurance and (2) a parent obtains coverage. DESIGN, SETTING, AND PARTICIPANTS: Oregon Experiment randomized natural experiment assessing the results of Oregon's 2008 Medicaid expansion. We used generalized estimating equation models to examine the longitudinal effect of a parent randomly selected to apply for Medicaid on their child's Medicaid or Children's Health Insurance Program (CHIP) coverage (intent-to-treat analyses). We used per-protocol analyses to understand the impact on children's coverage when a parent was randomly selected to apply for and obtained Medicaid. Participants included 14409 children aged 2 to 18 years whose parents participated in the Oregon Experiment. EXPOSURES: For intent-to-treat analyses, the date a parent was selected to apply for Medicaid was considered the date the child was exposed to the intervention. In per-protocol analyses, exposure was defined as whether a selected parent obtained Medicaid. MAIN OUTCOMES AND MEASURES: Children's Medicaid or CHIP coverage, assessed monthly and in 6-month intervals relative to their parent's selection date. RESULTS: In the immediate period after selection, children whose parents were selected to apply significantly increased from 3830 (61.4%) to 4152 (66.6%) compared with a nonsignificant change from 5049 (61.8%) to 5044 (61.7%) for children whose parents were not selected to apply. Children whose parents were randomly selected to apply for Medicaid had 18% higher odds of being covered in the first 6 months after parent's selection compared with children whose parents were not selected (adjusted odds ratio [AOR]=1.18; 95% CI, 1.10-1.27). The effect remained significant during months 7 to 12 (AOR=1.11; 95% CI, 1.03-1.19); months 13 to 18 showed a positive but not significant effect (AOR=1.07; 95% CI, 0.99-1.14). Children whose parents were selected and obtained coverage had more than double the odds of having coverage compared with children whose parents were not selected and did not gain coverage (AOR=2.37; 95% CI, 2.14-2.64). CONCLUSIONS AND RELEVANCE: Children's odds of having Medicaid or CHIP coverage increased when their parents were randomly selected to apply for Medicaid. Children whose parents were selected and subsequently obtained coverage benefited most. This study demonstrates a causal link between parents' access to Medicaid coverage and their children's coverage.

Use of intravitreal triamcinolone for the treatment of optic nerve edema in a patient with acute retinal necrosis: case report.

PURPOSE: To report the use of combined intravitreal triamcinolone and foscarnet therapy in a patient with active acute retinal necrosis. METHODS: Retrospective case report. A 40-year-old white woman with a history of ulcerative proctitis, intolerant to oral steroids, developed an aggressive case of acute retinal necrosis complicated by severe optic nerve edema resulting in 20/200 vision. RESULTS: Intravitreal foscarnet provided an initial improvement of the vitritis and retinitis; however, optic nerve edema and 20/200 vision persisted. After 2 weeks, intravitreal triamcinolone was combined with the foscarnet dose. Four days later, the optic nerve edema had resolved, the vision returned to 20/40, and the herpetic infection remained controlled. Eight months later, the patient had not experienced a retinal detachment, and acuity was 20/20. Oral steroids are an accepted adjunct to antiviral therapy in acute retinal necrosis; however, combined intravitreal steroid and antiviral therapy has not been previously reported. After combined intravitreal therapy was attempted, the patient experienced a rapid resolution of symptoms without exacerbating her retinitis. CONCLUSION: In select patients, combined intravitreal triamcinolone and foscarnet may be effective in treating acute retinal necrosis and its inflammatory sequelae.

Understanding how low-income families prioritize elements of health care access for their children via the optimal care model.

BACKGROUND: Insurance coverage alone does not guarantee access to needed health care. Few studies have explored what "access" means to low-income families, nor have they examined how elements of access are prioritized when availability, affordability, and acceptability are not all achievable. Therefore, we explored low-income parents' perspectives on accessing health care. METHODS: In-depth interviews with a purposeful sample of 29 Oregon parents who responded to a previously administered statewide survey about health insurance. Transcribed interviews were analyzed by a multidisciplinary team using a standard iterative process. RESULTS: Parents highlighted affordability and limited availability as barriers to care; a continuous relationship with a health care provider helped them overcome these barriers. Parents also described the difficult decisions they made between affordability and acceptability in order to get the best care they could for their children. We present a new conceptual model to explain these experiences accessing care with health insurance: the Optimal Care Model. The model shows a transition from optimal care to a breaking point where affordability becomes the driving factor, but the care is perceived as unacceptable because it is with an unknown provider. CONCLUSIONS: Even when covered by health insurance, low-income parents face barriers to accessing health care for their children. As the Affordable Care Act and other policies increase coverage options across the United States, many Americans may experience similar barriers and facilitators to health care access. The Optimal Care Model provides a useful construct for better understanding experiences that may be encountered when the newly insured attempt to access available, acceptable, and affordable health care services.

Using electronic health record data to evaluate preventive service utilization among uninsured safety net patients.

OBJECTIVE: This study compared the preventive service utilization of uninsured patients receiving care at Oregon community health centers (CHCs) in 2008 through 2011 with that of continuously insured patients at the same CHCs in the same period, using electronic health record (EHR) data. METHODS: We performed a retrospective cohort analysis, using logistic mixed effects regression modeling to calculate odds ratios and rates of preventive service utilization for patients without insurance, or with continuous insurance. RESULTS: CHCs provided many preventive services to uninsured patients. Uninsured patients were less likely than continuously insured patients to receive 5 of 11 preventive services, ranging from OR 0.52 (95% CI: 0.35-0.77) for mammogram orders to 0.75 (95% CI: 0.66-0.86) for lipid panels. This disparity persisted even in patients who visited the clinic regularly. CONCLUSION: Lack of insurance is a barrier to preventive service utilization, even in patients who can access care at a CHC. Policymakers in the United States should continue to address this significant prevention disparity.

Linkage methods for connecting children with parents in electronic health record and state public health insurance data.

The objective of this study was to develop methodologies for creating child-parent 'links' in two healthcare-related data sources. We linked children and parents who were patients in a network of Oregon clinics with a shared electronic health record (EHR), using data that reported the child's emergency contact information or the 'guarantor' for the child's visits. We also linked children and parents enrolled in the Oregon Health Plan (OHP; Oregon's public health insurance programs), using administrative data; here, we defined a 'child' as aged <19 years and identified potential 'parents' from among adults sharing the same OHP household identification (ID) number. In both data sources, parents had to be 12-55 years older than the child. We used OHP individual client ID and EHR patient ID numbers to assess the quality of our linkages through cross-validation. Of the 249,079 children in the EHR dataset, we identified 62,967 who had a 'linkable' parent with patient information in the EHR. In the OHP data, 889,452 household IDs were assigned to at least one child; 525,578 with a household ID had a 'linkable' parent (272,578 households). Cross-validation of linkages revealed 99.8 % of EHR links validated in OHP data and 97.7 % of OHP links validated in EHR data. The ability to link children and their parents in healthcare-related datasets will be useful to inform efforts to improve children's health. Thus, we developed strategies for linking children with their parents in an EHR and a public health insurance administrative dataset.

A review of the inflammatory chorioretinopathies: the white dot syndromes.

The white dot syndromes are a group of inflammatory chorioretinopathies of unknown etiology which have in common a unique and characteristic appearance of multiple yellow-white lesions affecting multiple layers of the retina, retinal pigment epithelium (RPE), choriocapillaris, and the choroid. They also have overlapping clinical features. We discuss acute retinal pigment epitheliopathy, multiple evanescent white dot syndrome, acute posterior multifocal placoid pigment epitheliopathy, multifocal choroiditis and panuveitis, acute zonal occult outer retinopathy, birdshot chorioretinopathy, and serpiginous choroidopathy. Some of these diseases are associated with a viral prodrome suggesting a possible viral/infectious etiology, while others are associated with a number of systemic processes suggesting an autoimmune etiology. We also review the presentation, evaluation/diagnosis, and treatment of these entities as well as the prognosis. Where applicable we discuss recent advancements in diagnosing and treating the white dot syndromes.

Subperiosteal hematoma in multiple settings.

Most reports of orbital hemorrhage do not distinguish among intraconal, extraconal, and subperiosteal hemorrhages, although several reports describe isolated subperiosteal hematomas as a separate entity. We report 3 cases of subperiosteal hematoma with different etiologies but similar progression of signs and symptoms. Each patient presented with spontaneous proptosis, rarely caused by orbital subperiosteal hematoma, measuring approximately 5 mm. Over the course of 4-10 days their conditions worsened and warranted intervention. All 3 cases were treated with anterior orbitotomy, and visual acuity returned to baseline following surgery in all.

Acute zonal occult outer retinopathy: vision loss in an active duty soldier.

Objective. To describe a case of acute zonal occult outer retinopathy (AZOOR) in an active duty patient. Methods. In this paper we studied fundus photographs, optical coherence tomograph, Humphrey visual field 30-2, fundus autofluorescence images, fluorescein angiograms, and electroretinography. Results. Exam findings on presentation: a 34-year-old American Indian female presented with bilateral photopsias, early RPE irregularity, and an early temporal visual field defect. Progression RPE damage and visual field defect along with ERG findings support final diagnosis of AZOOR. Conclusion. AZOOR may initially be identified as a broader category of disease called the "AZOOR complex of disorders". Specific visual field defects, ERG results, and clinical exam findings will help distinguish AZOOR from other similar disorders.

Retinitis pigmentosa and granular dystrophy: a rare and unique combination in one patient.

OBJECTIVE: To present a case of concurrent diagnoses, Retinitis Pigmentosa and Granular Corneal Dystrophy, discovered in one patient experiencing progressive vision loss. METHODS: In this case report we studied fundus photographs, anterior segment photographs, Goldman visual field, and electroretinography. RESULTS: Exam findings on presentation: A 58-year-old Korean female with bilateral crumb-like corneal stromal deposits, waxy pallor of the disc, attenuated vessels and bone spicules. Visual field deficit, ERG and clinical evaluation supports a final diagnosis of both Retinitis Pigmentosa and Granular Corneal Dystrophy. CONCLUSION: The presentation of both Retinitis Pigmentosa and Granular Corneal Dystrophy is a rare combination of vision loss. While both conditions are autosomal dominant and thus not, per se, extremely rare, they have not been documented to both contribute to vision loss in one patient.

Systemic absorption of mitomycin-C when used in refractive surgery.

PURPOSE: To determine whether corneal topical application of mitomycin-C (MMC) results in measurable plasma levels of systemic absorption. SETTING: Madigan Army Medical Center, Refractive Surgery Center, Fort Lewis, Washington, and Micro-Constants Laboratory, San Diego, California, USA. DESIGN: Case-control study. METHODS: The study comprised male and female active-duty soldiers having excimer laser photorefractive keratectomy with MMC. Patients who met inclusion criteria were asked to provide a blood sample immediately after being treated with MMC 0.2 mg/mL (0.02%) for 30 seconds. Human plasma samples were evaluated by liquid chromatography mass spectrometry to determine whether MMC was present. RESULTS: Thirty samples were submitted for evaluation. There was zero detection of MMC in the submitted samples. The quantifiable limit was greater than 10.0 ng/mL. All samples were below this. CONCLUSIONS: In this study of 30 patients with topical application of MMC for refractive surgery, there was no measurable evidence of systemic absorption. Although systemic absorption has been found with use in larger quantities, it was not known whether MMC toxicity concerns could be extrapolated to the refractive surgery population. This information allows counseling of patients on the extremely low likelihood of systemic absorption or toxicity following current techniques for refractive surgery. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.