Long-term Effects Of Radiation Research Articles

Cycles of solar ultraviolet radiation favor periodic expansions of cyanobacterial blooms in global lakes

Global warming and eutrophication are known to increase the prevalence of cyanobacterial blooms, posing a severe threat to the ecological stability and sustainability of water bodies. The long-term (over an annual time frame) effect of UV radiation on cyanobacterial blooms in lakes are rarely discussed though the substantial effects of high-intensity UV radiation on the growth inhibition of marine phytoplankton were studied. Here, we employed the datasets on surface solar UV radiation, nitrogen and phosphorus concentrations, and the annual scales and frequencies of cyanobacterial blooms in lakes across long-term spatial scales to probe the relationship of UV radiation with cyanobacterial blooms. The results indicated that enhanced solar UV radiation may unintentionally stimulate cyanobacterial growth and favor the expansions of cyanobacterial blooms in lakes around the world. The fluctuating UV radiation significantly affects the annual scales of cyanobacterial blooms in both eutrophic and oligotrophic lakes. Solar UV radiation enhances the positive impact of rising phosphorus levels on cyanobacterial blooms because UV radiation prompts the synthesis of polyphosphate in cyanobacteria cells, which helps cyanobacteria to alleviate the stress of UV light. The scales of cyanobacterial blooms are significantly impacted by solar UV radiation intensities as opposed to the annual frequency of cyanobacterial blooms. Furthermore, solar UV radiation fluctuation with a 9-year period over a 14-year main cycles significantly affects the periodicities of cyanobacterial blooms in global lakes, which provides a basis for predicting the peak value of the scales of cyanobacterial blooms in lakes. These findings opened up new avenues of inquiry into the mechanism and management strategies of cyanobacterial blooms in lakes worldwide.

Effects on Lung Tissue After Breast Cancer Radiation: Comparing Photon and Proton Therapies

PurposeIn breast cancer, improved treatment approaches that reduce injury to lung tissue and early diagnosis and intervention for lung toxicity are increasingly important in survivorship. The aims of this study are to (1) compare lung tissue radiographic changes in women treated with conventional photon radiation therapy and those treated with proton therapy (PT), (2) assess the volume of lung irradiated to 5 Gy (V5) and 20 Gy (V20) by treatment modality, and (3) quantify the effects of V5, V20, time, and smoking history on the severity of tissue radiographic changes. Patients and MethodsA prospective observational study of female breast cancer patients was conducted to monitor postradiation subclinical lung tissue radiographic changes. Repeated follow-up x-ray computed tomography scans were acquired through 2 years after treatment. In-house software was used to quantify an internally normalized measure of pulmonary tissue density change over time from the computed tomography scans, emphasizing the 6- and 12-month time points. ResultsCompared with photon therapy, PT was associated with significantly lower lung V5 and V20. Lung V20 (but not V5) correlated significantly with increased subclinical lung tissue radiographic changes 6 months after treatment, and neither correlated with lung effects at 12 months. Significant lung tissue density changes were present in photon therapy patients at 6 and 12 months but not in PT patients. Significant lung tissue density change persisted at 12 months in ever-smokers but not in never-smokers. ConclusionPatients treated with PT had significantly lower radiation exposure to the lungs and less statistically significant tissue density change, suggesting decreased injury and/or improved recovery compared to photon therapy. These findings motivate additional studies in larger, randomized, and more diverse cohorts to further investigate the contributions of treatment modality and smoking regarding the short- and long-term radiographic effects of radiation on lung tissue.

Current and Future Treatments, Prevention, Diagnosis on Retinoblastoma

The most frequent intraocular cancer in children is retinoblastoma. All pediatric patients with retinoblastoma must undergo genetic testing as a crucial part of their treatment. Retinoblastoma can also extend to the brain and spine, among other parts of the body. MRI and CT scans are two imaging procedures that may be used to detect retinoblastoma. The size and location of the retinoblastoma tumor in your child determine the optimal course of treatment. Chemotherapy is a type of medication that can be used to treat cancer. Chemotherapy can aid in tumor reduction, enabling subsequent therapies like radiation therapy, cryotherapy, or laser therapy to target any remaining cancer cells. Early eye examinations are crucial for diagnosis and care. If detected early, retinal blastoma is frequently treatable. A hereditary mutation may cause retinal tumors (retinoblastoma). External beam radiation therapy, cryotherapy, laser photocoagulation, thermotherapy, brachytherapy, and chemotherapy (intravitreal, intra-arterial, and systemic) are now included in the treatment of retinoblastoma in addition to the damaged globe. Long-term side effects of radiation and chemotherapy in retinoblastoma patients can include secondary cancers.

Demystifying the Role of Radiation Dose Bath in Brain Injury Using Machine Learning.

It is well known that high-dose radiation results in brain injury, the long-term effects of low-dose radiation, however, is uncertain. The purpose of this study was to investigate the role of low-dose bath on MRI changes, on both clinical and micro-architectural levels, using machine learning and computational methods. Six hundreds and fifty-six temporal lobe and 45 whole brain DVHs from patients treated for nasopharyngeal cancer (NPC) with IMRT or proton were included in this study. Temporal lobe injury (TLI) was defined as development of new T1 enhancement on MRI with or without surrounding T2 edema. Patients were divided randomly into train (50%) and test (50%) sets. Accuracy and AUC were used to evaluate the model performance. Minimum redundancy maximum relevance (MRMR) or SHAP algorithms was employed for feature selection. Support vector machine or random forest was used for classification. Automated cortical region segmentation using FreeSurfer v6 was performed in 33 patients with a minimum follow-up of 4 years. Architectural and biological MRI changes were determined in 34 different brain regions for each individual patient. The top-ranked temporal lobe features predicting TLI were V66/V38 for IMRT patients and V10 for proton patients with an AUC of 0.95 and 0.74, respectively. For whole brain, the top features were V16 and V13 with an AUC of 0.70. The rates of TLI at 5 years for V10-20(whole brain) ≥ 180cc and V10-20(whole brain) < 180 were 39.5% and 6.2%, respectively (HR = 5.5, 95% CI 1.4-22.0, p = 0.02). There were global changes in gray matter thickness, with most pronounced changes occurred in parietal lobe (-4.79%, p = 0.007) and occipital lobe (-5.68%, p = 0.03). Similarly, there were diffuse changes in white matter and subcortical volume. After radiation, the frontal lobe increased by 17.5% (p = 0.04), lateral ventricle 41% (p = 0.03), and choroid plexus 34.3% (p = 0.03). Low-dose radiation bath is associated with increased risk of temporal lobe injury and global disruption in brain architecture in NPC survivors.

Uncommon short- and long-term cardiological side effects of thoracic radiation: a report of two cases.

Radiotherapy is an essential treatment of more than 50% of oncohematological patients. Pericardial disorders and valvular heart disease are two common radiotherapy complications. Acute pericarditis is infrequent and usually underdiagnosed. Therefore, diagnostic suspicion and early treatment are mandatory to avoid the evolution to constrictive pericarditis. The prevalence of radiation-induced valvular heart disease is common in patients with a history of Hodgkin's lymphoma and breast cancer. It has distinctive characteristics from other etiologies and, thus, different therapeutic approaches. We present two cases of unusual complications of radiotherapy; the first one in the acute setting and the second one during the follow-up in the chronic phase. A multidisciplinary and individualized approach with specific considerations is decisive in the management of these patients.

A Cadaveric Simulation Study of Radiation Exposure to the Surgical Team during Fluoroscopic Spinal Surgery: How Much Are We Exposed?

The harmful effects of long-term low-dose radiation have been well known. There are few comprehensive reports evaluating concrete real exposure doses for each part of a surgeon, assistant surgeon, scrub nurse, and anesthesiologist associated with fluoroscopic spinal procedures. This research aimed to quantify the radiation exposure dose to surgical team members during C-arm fluoroscopy-guided spinal surgery. Seven fresh cadavers were irradiated for 1 and 3 min with C-arm fluoroscopy. The position of the X-ray source was under the table, over the table, and laterally. The radiation exposure doses were measured at the optic lens, thyroid gland, and hand in mannequins used to simulate surgical team members. A significant difference was observed in the radiation exposure dose according to the position of the X-ray source and the irradiated body area. The risk of scatter radiation exposure was the biggest for the lateral position (nearly 30-fold that for the position under the table). All radiation exposure doses were positively correlated with irradiation time. The occupational radiation exposure dose to surgical team members during C-arm fluoroscopy-guided lumbar spinal procedures varies according to the X-ray source position. Our findings would help surgical team members to know the risk of radiation exposure during various fluoroscopic procedures. Surgeons in particular need to reduce their radiation exposure by using appropriate shielding and technique.

The Effects of Whole Body Gamma Irradiation on Mice, Age-Related Behavioral, and Pathophysiological Changes.

We designed a study with the objective to determine the long-term radiation effects of gamma rays, originating from a single shot of Co60 at a dose of 2Gy on the 7-month-old male mice of the ICR line in 30days after the irradiation. The aim of this study was to characterize the behavior of animals using the Open Field test, immuno-hematological status, and morpho-functional changes in the central nervous system of mice. Irradiated animals displayed significantly different behavior in the OF in comparison with the control group. The radiation damage was confirmed by assessing the ratio of leukocytes in the peripheral blood of mice at a later date after exposure to Co60. After irradiation, a decrease in the glioneuronal complex was observed in the irritated group as well as histological changes of brain cells. To sum up, not only was the hematological status of mice altered upon the total gamma irradiation, but also their behavior, which was most probably due to significant alterations in the CNS. Study of influence of ionizing radiation on female mice, comparison between different age groups. Open Field test on the 30days after 2Gy of γ-rays and histological analysis indicated changes in behavioral patterns, leucocytes, and brain tissue.

Recognition and Management of the Long-term Effects of Cranial Radiation.

Cranial radiation is ubiquitous in the treatment of primary malignant and benign brain tumors as well as brain metastases. Improvement in radiotherapy targeting and delivery has led to prolongation of survival outcomes. As long-term survivorship improves, we also focus on prevention of permanent side effects of radiation and mitigating the impact when they do occur. Such chronic treatment-related morbidity is a major concern with significant negative impact on patient's and caregiver's respective quality of life. The actual mechanisms responsible for radiation-induced brain injury remain incompletely understood. Multiple interventions have been introduced to potentially prevent, minimize, or reverse the cognitive deterioration. Hippocampal-sparing intensity modulated radiotherapy and memantine represent effective interventions to avoid damage to regions of adult neurogenesis. Radiation necrosis frequently develops in the high radiation dose region encompassing the tumor and surrounding normal tissue. The radiographic findings in addition to the clinical course of the patients' symptoms are taken into consideration to differentiate between tissue necrosis and tumor recurrence. Radiation-induced neuroendocrine dysfunction becomes more pronounced when the hypothalamo-pituitary (HP) axis is included in the radiation treatment field. Baseline and post-treatment evaluation of hormonal profile is warranted. Radiation-induced injury of the cataract and optic system can develop when these structures receive an amount of radiation that exceeds their tolerance. Special attention should always be paid to avoid irradiation of these sensitive structures, if possible, or minimize their dose to the lowest limit.

Performance evaluation of pulse shape discrimination capable organic scintillators for space applications

Scintillators with pulse-shape discrimination (PSD) capability are of great interest to many fields in the scientific community. The ability to discern a gamma ray from a neutron using PSD varies between different types of scintillator materials and dopants. A new generation of organic scintillator materials with PSD capability were studied to determine their radiation hardness to neutron and gamma-ray radiation. The PSD capability, average pulse shapes, and light output of four types of organic scintillator were characterized before and after neutron and gamma-ray irradiation. The main goal of this investigation is to study the effects of long-term irradiation that may be experienced in space applications on the light output and particle discriminating capabilities of each material. EJ-270, EJ-276, organic glass, and Stilbene were tested. Damage due to neutron irradiation (displacement damage) was not observed in any of the scintillators up to 2.56×1011 n/cm2, except for Stilbene which showed a small (12%) decrease in light output. All scintillators presented some light output reduction after gamma-ray irradiation (total ionizing dose), with reductions of 17% (EJ-276 and OGS), 32% (EJ-270), and 42% (Stilbene) observed immediately after 100 kRad.

The effect of aboveground long-term low-dose ionizing radiation on soil microbial diversity and structure

Studies investigating the diversity and structure of soil microbial systems in response to ionizing radiation are scarce. In particular, effects of long-term low-dose radiation is rarely studied because of its unique conditions. In this study, an area in Chengdu, China, which has been irradiated by the radionuclide thorium-232 for more than 10 years was investigated. Four groups of samples with absorbed dose rates ranging from 192.906 ± 5.05 to 910.964 ± 41.09 nGy/h were collected to analyze the compositional and functional changes of the soil microbial systems in the region. The diversity and structure of the soil microbial systems were determined using high-throughput sequencing. Our results showed that long-term low-dose ionizing radiation had no significant effect on soil bacterial diversity, but had a great impact on fungal diversity. Long-term ionizing radiation strongly affected soil microbial community structure. Long-term low-dose ionizing radiation was shown to have a promoting effect on iron-oxidizing bacteria and ectomycorrhizal fungi and have an inhibiting effect on predatory or parasitic fungi, further affecting the soil C/N ratio. This study is of great reference significance for future research on the impact of long-term low-dose ionizing radiation on soil ecosystems.

Extremely Low Frequency-Electromagnetic Fields (ELF-EMF) Can Decrease Spermatocyte Count and Motility and Change Testicular Tissue

Substantial evidence indicates that exposure to extremely low frequency-electromagnetic fields (ELF-EMFs) affects male reproductive system. The goal of this study was to evaluate the effects of long-term irradiation with ELF-EMF on sperm quality and quantity and testicular structure. In this case-control study, sixty male Sprague-Dawley rats were randomly divided into six groups. Experimental groups were exposed to ELF-EMF (50 Hz EMF, 100 µT) for either 1 h/day for 52 days (Group 1), 4 h/day for 52 days (Group 3), 1 h/day for 5 days (Group 5), 4 h/day for 52 days (Group 7). Groups 2, 4, 6 and 8 were only sham exposed at durations equal to Groups 1, 3, 5 and 7, respectively. Both count and motility of sperms were significantly decreased in animals exposed to ELF-EMF (1 h/day for 52 days, 4 h/day for 52 day, and 4 h/day for 5 days) compared to the sham-exposed groups (P<0.05). Serum testosterone levels showed a significant decrease in the animals exposed to ELF-EMF (4 h/day for 5 days) compared to the control groups (P<0.05). A significant decrease was observed in the volume of the seminiferous tubules, seminiferous tubules epithelium and interstitial tissue in the animals exposed to ELF-EMF for 4 h/day for 5 days. Tubules length was also reduced by 18% in animals exposed to ELF-EMF (4 h/day for 5 days). Our results show that ELF-EMF can reduce spermatocyte count and motility and is able to induce structural changes in testicular tissue.

Abstract No. 540 Correlations of Ionizing Radiation to Histopathologic Changes and Long-Term Biological Effects of Radiation

Abstract No. 540 Correlations of Ionizing Radiation to Histopathologic Changes and Long-Term Biological Effects of Radiation

Morphology and Performance of PolyVinyl Chloride Thin Films Doped with Polyorganosilanes against Photodegradation

The importance of polymeric additives has taken an important role in industrial technology and its development and the increase in the consumption period of industrial products, especially plastic products. Therefore, a different type of polymeric additive was used, which can be classified as another type of polymeric additive, where three types of polymers were synthesized as polymeric additives. These polymers differ from each other only in stereo geometry. Three geometric shapes of the polymer were synthesized, namely, ortho, meta, and para polymers. They were studied as photo stabilizers for PVC and compared as the best photostabilizer for PVC. Polyorganosiloxane was invented by various technologies. Polyorganosilanes and poly(vinyl chloride) (PVC) were combined to create homogeneous films. Various methods were used to investigate the effects of long-term irradiation on polyorganosilane-containing films. The development of side products containing polyene and carbonyl groups was observed in the infrared spectra of PVC films before, during, and after irradiation. The absorption bands' intensities of the functional groups associated with the polyorganosilanes were lower when it was present. Furthermore, it was observed that the weight of PVC films dropped less when irradiating them after hybridization with polyorganosilanes. In the presence of polyorganosilanes, there was also a minor alteration in the surface of irradiated PVC. Photodegradation of PVC is inhibited by polyorganosilanes. Hence, the role of polyorganosilanes to stabilize PVC against UV exposure has been studied.

Radiation-aware analog circuit design via fully-automated simulation environment

As a result of increased interest in space applications, radiation-aware circuit design has become a major concern to guarantee the safe operation of electronic systems operating under extreme space conditions. As the first step, several ad-hoc simulation approaches have been developed in analog and digital domains to estimate the functional behavior of circuits exposed to high radiation. However, most of these tools are application specific and stand-alone (not integrated into the simulation tools). Also, several commercial CAD solutions exist; however, access to these tools is limited due to security measures. To this end, we have developed a well-equipped, SPICE-integrated, and free-to-access simulation tool, RadiSPICE, capable of running statistical radiation simulations and performing extended temperature and sensitivity analyses. By using RadiSPICE, one can readily predict the functional behavior of circuits after long-term or short-term radiation effects. Moreover, the sensitivity analysis reveals vulnerabilities of the design against radiation and provides valuable design hints to the designer to make circuits radiation-hardened. To demonstrate the proposed tool, we have performed several experiments on two analog building blocks with different topologies (bandgap reference and comparator circuits) using RadiSPICE and discussed the robustness of the designs in detail.

Evidence for Persistent Radiation-Related Injury to the Immune System in Patients With Local Breast Cancer

Severe and prolonged lymphopenia is well described in the literature as a consequence of local radiation and is associated with early death and impaired responses to immunotherapy. In animals, localized radiation results in histologic changes in lymph nodes that are distant from the radiation field. The sustained effects of radiation on distant lymph nodes in humans has not been previously described. This study was designed to assess changes in lymph nodes architecture outside the radiation field in women with breast cancer months after radiation treatment. Seven women were enrolled on a protocol to collect a distal abdominal lymph node during breast reconstruction with a deep inferior epigastric perforators (DIEP) flap. Five patients previously received chest wall irradiation on average 608 days prior to reconstruction while two patients did not receive radiation. The abdominal lymph node was compared to the initial (pre-radiation) mastectomy surgery lymph node by a blinded hematopathologist. The lymph node cellularity was graded by density score. The five patients who underwent radiation had striking reductions in their lymph node cellularity: average baseline score of 3 ± 1.2 with post lymph node density score of 1.2 ± 0.5, when compared to the two unirradiated patients: average baseline score of 4 with post lymph node density score of 3 ± 1.4. This small study suggests that localized radiation may have long-term impacts on distal lymph node basins in humans as has been seen in animals. Future studies evaluating prolonged systemic lymphopenia following radiation are needed to document the long-term systemic effects of local radiation, and the overall implications of this finding.

Radiation Exposure and Lifetime Attributable Risk of Cancer Incidence and Mortality from Low- and Standard-Dose CT Chest: Implications for COVID-19 Pneumonia Subjects.

Since the novel coronavirus disease 2019 (COVID-19) outbreak, there has been an unprecedented increase in the acquisition of chest computed tomography (CT) scans. Nearly 616 million people have been infected by COVID-19 worldwide to date, of whom many were subjected to CT scanning. CT exposes the patients to hazardous ionizing radiation, which can damage the genetic material in the cells, leading to stochastic health effects in the form of heritable genetic mutations and increased cancer risk. These probabilistic, long-term carcinogenic effects of radiation can be seen over a lifetime and may sometimes take several decades to manifest. This review briefly describes what is known about the health effects of radiation, the lowest dose for which there exists compelling evidence about increased radiation-induced cancer risk and the evidence regarding this risk at typical CT doses. The lifetime attributable risk (LAR) of cancer from low- and standard-dose chest CT scans performed in COVID-19 subjects is also discussed along with the projected number of future cancers that could be related to chest CT scans performed during the COVID-19 pandemic. The LAR of cancer Incidence from chest CT has also been compared with those from other radiation sources, daily life risks and lifetime baseline risk.

Effects of 2.45 GHz Non-Ionizing Radiation on Anxiety-Like Behavior, Gene Expression, and Corticosterone Level in Male Rats.

Introduction: The effects of short-term and long-term exposures to 2.45 GHz radiofrequency electromagnetic radiation (RF-EMR) on anxiety-like behavior, corticosterone level, and gene expression were investigated. The goal of this study was to explore the effect of electromagnetic fields of 2.45 GHz on clinical signs such as body weight and anxiety-like behavior, including the elevated plus maze test and open-field test, and also on messenger RNA (mRNA) expression of Bax (Bcl2-associated x) and Bcl-2 (B-cell lymphoma 2) genes on the cognitive memory functions in an animal model of rats. Methods: The animals were classified into eight groups, sham groups and exposed groups for short-term and long-term exposures to the same dose of RF-EMR for one hour daily. The Wi-Fi equipment in the sham control group was not turned on during the experiment. Both genes were further confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR). The semi-quantitative PCR method of electromagnetic fields in the 2.45 GHz range impacted the expression of Bax and Bcl-2 genes in the rat's memory. Results: The present study exhibited that short-term radiation could decrease the percentage of entry into the open arm and the percentage of time spent, while there were no substantial impacts on the long-term radiation effect. Our data support the hypothesis that short-term exposure worked as a systemic stressor, raising plasma corticosterone and changing glucocorticoid receptor expression in the hippocampus. Conclusion: Additional research on this specific frequency and amount of radiation is required to discover strategies for protecting the nervous system from the detrimental effects of RF-EMR radiation.

Aging of Polymeric Insulators under Various Conditions and Environments: Another Look

Polymeric insulators have lightweight, excellent hydrophobicity and convenient transportation and installation. They are widely used in the external insulation for distribution and transmission lines. However, due to the long-term effects of pollution, ultraviolet radiation, discharge, temperature, humidity, altitude and other natural and complex environmental and service factors, the silicone rubber and other materials of polymeric insulators gradually age and lose their hydrophobicity and electrical insulation characteristics. The operability is significantly reduced, which seriously affects the safety and reliability of the power system. Hence, there is a need for assessing and evaluating the long-term aging and degradation of polymeric insulators under various operating conditions and environments. In this review, the various aging and characterization techniques of the polymeric insulators and their aging performance under the action of multiple factors are discussed. To enhance the performance of polymeric insulators, nano-coating, surface treatment and other techniques are also indicated. In addition, future potential fields that should be explored from a high-voltage electrical insulation perspective are also presented.

Risk of Diabetes Mellitus after Radiotherapy for Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

<h3>Purpose/Objective(s)</h3> The long-term effect of radiation on pancreas has been mostly studied for pediatric patients with the lack of individual radiation dosimetric data. The purpose of this study was to investigate the effect of radiotherapy (RT) on the risk of newly developed diabetes mellitus (DM) in patients with gastric mucosa-associated lymphoid tissue lymphoma (GML) using individual radiation dosimetric analysis. <h3>Materials/Methods</h3> We retrospectively reviewed 225 patients without history of DM who received curative aim treatment for stage IE GML between August 2007 and June 2020. Involved site RT to the whole stomach was delivered in 83 patients (36.9%). The pancreas was delineated in each patient's computerized tomography scan for dosimetric analysis. <h3>Results</h3> At a median follow-up time of 49.0 months (range, 3.0-155.3 months), the 3-year cumulative incidence of DM was 3.9% in all patients, and 7.9% and 1.6% in patients who received and did not receive RT, respectively (p=0.009). The mean pancreatic dose (D_mean) was independently associated with DM (p=0.027). As a result of recursive partitioning analysis, patients were classified into low (D_mean <21 Gy), intermediate (D_mean ≥21 Gy and BMI <27.0kg/m²), and high-risk groups (D_mean ≥21 Gy and BMI ≥27.0kg/m²) with 5-year DM incidence of 1.5%, 6.3%, and 54.3%, respectively (p<0.001). <h3>Conclusion</h3> Our results indicate that incidental irradiation to the pancreas can increase the risk of DM, which was dependent on pancreas D_mean. In addition, not only reducing pancreas D_mean but also controlling BMI may need to be combined to effectively prevent DM after RT.

Preclinical Research Platform for Ocular FLASH Irradiation

<h3>Purpose/Objective(s)</h3> Normal tissue sparing effects from FLASH radiotherapy (RT) are potentially transformative for the treatment of ocular cancers. Reducing damage to the abundant at-risk structures within the eye can prospectively increase visual retention rates, relax treatment margins, and eliminate the need for motion tracking by surgically implanted fiducials. To date, no prior work has explored FLASH-RT effects in the context of the eye. In this work, we have conducted a pilot study of x-ray FLASH effects for ocular irradiation in a preclinical mouse model by measuring the functional and pathological changes in healthy eyes following FLASH or conventional (CONV) dose rate irradiation. <h3>Materials/Methods</h3> An immobilization device was designed to enable focal irradiation to a single mouse eye using a FLASH-capable rotating anode x-ray tube. A 5 mm diameter lead collimator was manufactured to encompass the 3 mm target of the entire eye. Dose and dose rate measurements were performed with calibrated radiographic EBT3 films. Cone-beam CTs were acquired of four C57BL6J mice in immobilization to confirm setup reproducibility, quantified by the mean Hausdorff distance between bone segmentations. Healthy 8-week-old C57BL6J mice were irradiated with 150 kVp x-rays to doses of 21 Gy or 34 Gy at FLASH (right eye) and CONV (left eye) dose rates, respectively. Both eyes were irradiated to limit the influence of varying baseline vision between animals in our analysis. Visual acuity was assessed in 3 mice per dose level using scotopic electroretinography (ERG) up to 2 months post irradiation. Histopathological changes were assessed through H&E staining of harvested eyes. <h3>Results</h3> Mouse setup in our immobilization device was highly reproducible, with a mean Hausdorff distance of 0.34 ± 0.10 mm. Measured dose rates within the field were 67.0 ± 1.9 Gy/s and 1.2 ± 0.1 Gy/s at FLASH and CONV settings, respectively. ERGs revealed that FLASH-irradiated eyes at 21 Gy retained visual function up to 2 months post irradiation, while 21 Gy CONV induced blindness at all sampled time points with more severe surrounding skin effects. At 34 Gy, all eyes were blinded within 1 week, with comparable skin toxicities in the irradiated areas regardless of dose rate. Pathological assessment showed a loss of the photoreceptor layer of the retina from CONV irradiation, which remained intact in FLASH-treated mice. <h3>Conclusion</h3> We have developed a novel platform to study x-ray FLASH effects from ocular irradiation in mice. Functional ERG assay revealed a preservation of visual function from 21 Gy at FLASH dose rates that was not present from 21 Gy CONV. Differential damages between FLASH and CONV irradiations were confirmed through histopathology. This first demonstration of FLASH normal tissue sparing effects in a mouse eye model presents a unique and promising translation opportunity for clinical FLASH treatment. Further studies are ongoing to explore the long-term effects of FLASH radiation on vision and its efficacy on intraocular tumors.