AIBI Modified Mesoporous Copper Sulfide Nanocomposites for Efficient Non-Oxygen Dependent Free Radicals-Assisted Photothermal Therapy in Uveal Melanoma.

Uveal melanoma (UM) is an ocular cancer predominantly affecting adults, characterized by challenging diagnostic outcomes. This research endeavors to develop an innovative multifunctional nanocomposite system sensitive to near-infrared (NIR) radiation, serving as both a non-oxygen free-radical generator and a photothermal agent. The designed system combines azobis isobutyl imidazoline hydrochloride (AIBI) with mesoporous copper sulfide (MCuS) nanoparticles. MCuS harnesses NIR laser energy to induce photothermal therapy, converting light energy into heat to destroy cancer cells. Simultaneously, AIBI is activated by the NIR laser to produce alkyl radicals, which induce DNA damage in remaining cancer cells. This distinctive feature equips the designed system to selectively eliminate cancers in the hypoxic tumor microenvironment. MCuS is also beneficial to scavenge the overexpressed glutathione (GSH) in the tumor microenvironment. GSH generally consumes free radicals and hiders the PDT effect. To enhance control over AIBI release in cancer cells, 1-tetradecyl alcohol (TD), a phase-changing material, is introduced onto the surface of MCuS nanoparticles to create the final AMPT nanoparticle system. In vitro and in vivo experiments confirm the remarkable anti-tumor efficacy of AMPT. Notably, the study introduces an orthotopic tumor model for UM, demonstrating the feasibility of precise and effective targeted treatment within the ocular system.

Exosomes in the visual system: New avenues in ocular diseases.

Exosomes are a subgroup of membrane-bound extracellular vesicles secreted by all cell types and present virtually in all biological fluids. The composition of exosomes in the same cell type varies in healthy and disease conditions. Hence, exosomes research is a prime focus area for clinical research in cancer and numerous age-related metabolic syndromes. Functions of exosomes include crucial cell-to-cell communication that mediates complex cellular processes, such as antigen presentation, stem cell differentiation, and angiogenesis. However, very few studies reported the presence and role of exosomes in normal physiological and pathological conditions of specialized ocular tissues of the eye and ocular cancers. The eye being a protected sense organ with unique connectivity with the rest of the body through the blood and natural passages, we believe that the role of exosomes in ocular tissues will significantly improve our understanding of ocular diseases and their interactions with the rest of the body. We present a review that highlights the existence and function of exosomes in various ocular tissues, their role in the progression of some of the neoplastic and non-neoplastic conditions of the eyes.

Exploring the FGF/FGFR System in Ocular Tumors: New Insights and Perspectives.

Ocular tumors are a family of rare neoplasms that develop in the eye. Depending on the type of cancer, they mainly originate from cells localized within the retina, the uvea, or the vitreous. Even though current treatments (e.g., radiotherapy, transpupillary thermotherapy, cryotherapy, chemotherapy, local resection, or enucleation) achieve the control of the local tumor in the majority of treated cases, a significant percentage of patients develop metastatic disease. In recent years, new targeting therapies and immuno-therapeutic approaches have been evaluated. Nevertheless, the search for novel targets and players is eagerly required to prevent and control tumor growth and metastasis dissemination. The fibroblast growth factor (FGF)/FGF receptor (FGFR) system consists of a family of proteins involved in a variety of physiological and pathological processes, including cancer. Indeed, tumor and stroma activation of the FGF/FGFR system plays a relevant role in tumor growth, invasion, and resistance, as well as in angiogenesis and dissemination. To date, scattered pieces of literature report that FGFs and FGFRs are expressed by a significant subset of primary eye cancers, where they play relevant and pleiotropic roles. In this review, we provide an up-to-date description of the relevant roles played by the FGF/FGFR system in ocular tumors and speculate on its possible prognostic and therapeutic exploitation.

Subretinal Fluid Optical Density and Spectral-Domain Optical Coherence Tomography Characteristics for the Diagnosis of Circumscribed Choroidal Hemangioma.

PURPOSE: To investigate spectral domain-optical coherence tomography (SD-OCT) features of untreated circumscribed choroidal hemangioma (CCH), and the optical density (OD) of the associated subretinal fluid (SRF). PROCEDURES: This international retrospective multicenter study conducted at 5 tertiary retina referral centers included 34 patients with symptomatic CCH imaged on SD-OCT. CCH surface, size, and overlying retinal changes and OD ratio (ODR) were evaluated. RESULTS: The mean ODR of the SRF was 0.808 ± 0.287. Tumor base measured on ultrasound correlated significantly with the ODR (p = 0.012). ODR values in cases of CCH were similar to those of choroidal metastasis, but significantly lower than those of choroidal melanoma (p = 0.006). Thirty-two out of 34 cases (94%) presented with a regular smooth choroidal surface. OCT demonstrated SRF overlying the CCH in 29 eyes (85%). The presence of SRF correlated significantly with a larger basal tumor diameter (p = 0.035). OCT displayed sub- and intraretinal hyperreflective foci, correlating with both larger maximal retinal thickness overlying the tumor (p = 0.031) and the amount of SRF (p = 0.016) in 29 eyes (85%). CONCLUSION: CCH displays typical findings on SD-OCT. ODR is a new important tool in the differential diagnosis of choroidal tumors and should be considered for enhancing the accuracy of diagnosing CCH. This benefit is especially relevant for cases in which the presentation of CCH is atypical.

Visualization and Quantitative 3D Analysis of Intraocular Melanoma and Its Vascularization in a Hamster Eye.

A tumor vasculature network undergoes intense growth and rebuilding during tumor growth. Traditionally, vascular networks are histologically examined using parameters such as vessel density determined from two-dimensional slices of the tumor. Two-dimensional probing of a complicated three-dimensional (3D) structure only provides partial information. Therefore, we propose the use of microcomputed tomography (micro-CT) imaging to analyze the evolution of a tumor vasculature in an experimental ocular tumor model. A Bomirski Hamster Melanoma was implanted in the anterior chamber of a hamster eye. Ultrasound (US) imaging of the same tumor was performed in vivo, and the vascular results obtained using the two methods were compared. Normal ocular tissues, a tumor, and a tumor vascular structure were revealed with high accuracy using micro-CT. The vessels that grew within the tumor were chaotic, leaky, and contained many convoluted micro-vessels and embolizations. They comprised 20-38% of the tumor mass. The blood flow in the larger functional vessels was in the range from 10 to 25 mm/s, as determined by in vivo Doppler US. The micro-CT imaging of the hamster eyeball enabled both qualitative and quantitative 3D analyses of the globe at a histological level. Although the presented images were obtained ex vivo, micro-CT noninvasive imaging is being developed intensively, and high-resolution in vivo imaging is feasible.

Retinoblastoma: An update.

Retinoblastoma is the most common ocular malignancy in children, and is initiated by mutation of the RB1 gene. The tumor may be unilateral or bilateral and can be inherited. Overall survival, eye salvage, and preservation of vision are largely dependent on the stage of disease at presentation. Despite a recently enhanced understanding of the etiology of retinoblastoma, the mortality associated with it remains high worldwide. This may relate to a continuing lack of awareness of the lesion by laypersons, and unavailability of modern treatment facilities. Adverse outcomes are also caused by the occurrence of secondary malignancies after treatment of retinoblastoma in childhood. Early diagnosis, multidisciplinary treatment, and genetic counseling are all priorities in the management of this tumor.

NKT cells act through third party bone marrow-derived cells to suppress NK cell activity in the liver and exacerbate hepatic melanoma metastases.

Uveal melanoma (UM) is the most common intraocular tumor in adults and liver metastasis is the leading cause of death in UM patients. We have previously shown that NKT cell-deficient mice develop significantly fewer liver metastases from intraocular melanomas than do wild-type (WT) mice. Here, we examine the interplay between liver NKT cells and NK cells in resistance to liver metastases from intraocular melanomas. NKT cell-deficient CD1d(-/-) mice and WT C57BL/6 mice treated with anti-CD1d antibody developed significantly fewer liver metastases than WT mice following either intraocular or intrasplenic injection of B16LS9 melanoma cells. The increased number of metastases in WT mice was associated with reduced liver NK cytotoxicity and decreased production of IFN-γ. However, liver NK cell-mediated cytotoxic activity was identical in non-tumor bearing NKT cell-deficient mice and WT mice, indicating that liver metastases were crucial for the suppression of liver NK cells. Depressed liver NK cytotoxicity in WT mice was associated with production of IL-10 by bone marrow-derived liver cells that were neither Kupffer cells nor myeloid-derived suppressor cells and by increased IL-10 receptor expression on liver NK cells. IL-10(-/-) mice had significantly fewer liver metastases than WT mice, but were not significantly different from NKT cell-deficient mice. Thus, development of melanoma liver metastases is associated with upregulation of IL-10 in the liver and an elevated expression of IL-10 receptor on liver NK cells. This impairment of liver NK activity is NKT cell-dependent and only occurs in hosts with melanoma liver metastases.

The effect of intra- and inter-fractional motion on target coverage and margins in proton therapy for uveal melanoma.

INTRODUCTION: This study aims to assess the effective lateral margin requirements for target coverage in ocular proton therapy (OPT), considering the unique challenges posed by eye motion and hypofractionation. It specifically addresses the previously unaccounted-for uncertainty contribution of intra-fractional motion, in conjunction with setup uncertainties, on dosimetric determination of lateral margin requirements. Method: The methodology integrates dose calculations from the in-house developed treatment planning system OCULARIS with measured intra-fractional motion, patient models from EyePlan and Monte Carlo (MC) sampling of setup uncertainties. The study is conducted on 16 uveal melanoma patients previously treated in the OPTIS2 treatment room at the Paul Scherrer Institute (PSI). Results: The retrospective simulation analysis highlights a significant impact of non-systematic factors on lateral margin requirements in OPT. Simulations indicate that reducing the 2.5 mm clinical lateral margin, represented by a 2.1 mm margin in this work, would have resulted in inadequate target coverage for two patients, revealing a greater impact of non-systematic factors on lateral margin requirements. Conclusions: This work characterizes intra-fractional motion in 16 OPT patients and identifies limitations of clinical margin selection protocols for OPT applications. A novel framework was introduced to assess margin sufficiency for target coverage. The findings suggest that prior research underestimated non-systematic factors and overestimated systematic contributions to lateral margin components. This re-evaluation highlights the critical need to prioritize the management of non-systematic uncertainty contributions in OPT.

[Metastasis in the periocular region]. / Metastase in der periokulären Region.

Orbital and periocular metastatic tumors used to be considered very rare; however, with the constant updating of drugs and detection methods for cancer treatment, new chemotherapies and radiation treatments are being used. The life expectancy of cancer patients has become longer and periocular metastases are becoming easier to detect. Our knowledge of this rare disease of metastases also needs to be updated. This article reviews the incidence, symptomatic presentation, clinical features, diagnostic approaches and current treatment of metastatic tumors of the orbit and ocular adnexa in these patients.

Quantitative Biomarkers Derived from a Novel, Contrast-Free Ultrasound, High-Definition Microvessel Imaging for Differentiating Choroidal Tumors.

Angiogenesis has an essential role in the de novo evolution of choroidal melanoma as well as choroidal nevus transformation into melanoma. Differentiating early-stage melanoma from nevus is of high clinical importance; thus, imaging techniques that provide objective information regarding tumor microvasculature structures could aid accurate early detection. Herein, we investigated the feasibility of quantitative high-definition microvessel imaging (qHDMI) for differentiation of choroidal tumors in humans. This new ultrasound-based technique encompasses a series of morphological filtering and vessel enhancement techniques, enabling the visualization of tumor microvessels as small as 150 microns and extracting vessel morphological features as new tumor biomarkers. Distributional differences between the malignant melanomas and benign nevi were tested on 37 patients with choroidal tumors using a non-parametric Wilcoxon rank-sum test, and statistical significance was declared for biomarkers with p-values < 0.05. The ocular oncology diagnosis was choroidal melanoma (malignant) in 21 and choroidal nevus (benign) in 15 patients. The mean thickness of benign and malignant masses was 1.70 ± 0.40 mm and 3.81 ± 2.63 mm, respectively. Six HDMI biomarkers, including number of vessel segments (p = 0.003), number of branch points (p = 0.003), vessel density (p = 0.03), maximum tortuosity (p = 0.001), microvessel fractal dimension (p = 0.002), and maximum diameter (p = 0.003) exhibited significant distributional differences between the two groups. Contrast-free HDMI provided noninvasive imaging and quantification of microvessels of choroidal tumors. The results of this pilot study indicate the potential use of qHDMI as a complementary tool for characterization of small ocular tumors and early detection of choroidal melanoma.

Guiding function of positron emission tomography-computed tomography examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma.

AIM: To explore the role of positron emission tomography-computed tomography (PET-CT) examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma (OAML). METHODS: The general clinical data, postoperative PET-CT results, treatment regimens, and the prognosis of 21 histopathologically confirmed OAML patients between October 2017 and September 2021 were collected. Among the 21 patients, five patients underwent surgical treatment alone, 13 patients underwent surgical treatment combined with radiotherapy, and three patients underwent surgical treatment combined with chemotherapy. RESULTS: The follow-up period ranged from 8 to 79mo, with four cases of recurrence and no deaths. Through PET-CT examination, two patients exhibited both local ocular metabolic elevation and systemic metastasis, and one of these patients had cervical lymph node metastasis, while the other had submandibular and parotid gland metastasis. Nine patients showed only local ocular metabolic elevation, while 10 patients had no abnormal metabolic activity locally. CONCLUSION: PET-CT examination plays a crucial role in detecting residual lesions and recurrence following tumor resection, aiding in precise disease staging, and facilitating the development of personalized treatment plans, ultimately improving patient prognosis.

Plaque brachytherapy - Radiating positivity.

Background: Plaque brachytherapy is an evolving, yet effective globe and vision-sparing modality for the treatment of intraocular tumors by transscleral irradiation of the tumor base with a radioactive implant. The American Brachytherapy Society (ABS) along with the collaboration of the international multicenter Ophthalmic Oncology Task Force (OOTF) was assembled to reach a consensus regarding establishing practice guidelines and setting standards of care for intraocular tumors. The advent of plaque brachytherapy has revolutionized the outcomes of intraocular tumors, thus ensuring globe salvage, reducing morbidity and mortality, and avoiding cosmetic disfigurement. A well-planned dosimetry for plaque brachytherapy results in achieving local tumor control and excellent prognosis. Purpose: This technique provides the advantage of focal radiation, thus eliminating the damage to the adjacent structures, minimal periorbital tissue damage, absence of cosmetic disfigurement owing to lack of retarded bone growth as seen in external beam radiotherapy. Thus, it reduces the risk of metastasis, and with the recent advances, it provides a shorter duration of treatment. Synopsis: : In this video, we shall display the concept of plaque brachytherapy, the various types of plaques available, different radiations sources, planning dosimetry and calculations, target disease spectrum, surgical placement, and post-radiation outcomes in terms of local tumor control and prognosis. Highlights: This video highlights the history, basic principles and techniques of plaque brachytherapy and provides an understanding of its applications in the world of ocular oncology. Video link: https://youtu.be/7PX0mDQETRY.

Radiation retinopathy following episcleral brachytherapy for intraocular tumors: Current treatment options.

Radiation retinopathy (RR) and radiation maculopathy (RM) can occur as a result of uveal melanoma radiation treatment and after irradiation of other head and neck extraocular tumors, even with precise targeting techniques, such as stereotactic or proton beam radiotherapy. This review provides an overview of the current understanding of potential radiation damage to ocular tissues, and how recent developments in ophthalmic multimodal imaging techniques and treatment modalities have improved managing options. Several treatment strategies have been employed so far for the management of RR, including laser photocoagulation, intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents or glucocorticosteroids and surgery. The use of intravitreal anti-VEGFs or dexamethasone implants have significantly altered the final visual outcome for uveal melanoma patients. As a prophylaxis, a few different strategies were proposed, but still there is a lack of large randomized clinical trials supporting these approaches and clear clinical guidelines for daily practice. Early detection and proper treatment are crucial in preventing or reducing vision loss, and improving patients' quality of life. Close monitoring and timely intervention are essential for successful management.

[OCULO-ORBITAL TUMOURS AT THE NATIONAL UNIVERSITY HOSPITAL CENTRE OF BANGUI (CNHUB), CENTRAL AFRICAN REPUBLIC, IN 2022]. / TUMEURS OCULO-ORBITAIRES AU CENTRE NATIONAL HOSPITALIER UNIVERSITAIRE DE BANGUI (CNHUB), RÉPUBLIQUE CENTRAFRICAINE, EN 2022.

Introduction: Oculo-orbital tumors are common. Their clinical and histological features are multiple. The management of oculo-orbital tumors is a real challenge in sub-Saharan Africa, especially in our context. The aim of this study was to contribute to the improvement of the management of oculo-orbital tumors at the Bangui Teaching Hospital (CNHUB). Methodology: This was a prospective, observational study of oculo-orbital tumors over 12 months from January 1 to December 31, 2022 in the ophthalmology department of the CNHUB. All consenting patients with histologically proven tumors of the eyeball and/or its adnexa were included in this study, regardless of age and sex.The parameters studied were:epidemiological: age, sex, occupation, origin;clinical: time of consultation, functional signs and associated signs, physical examination signs, risk factors;paraclinical: report of the anatomopathological examination of the operating room;therapeutic: treatment modalities (chemotherapy, surgery, palliative treatment, radiotherapy).These data were collected on a pre-established survey form for direct administration. The processing and the production of the results were carried out with Excel and Epi Info 7.0 software. Results: We included 97 patients with a mean age of 37.5 years, ranging from 2 to 70 years. There was a male predominance (sex-ratio = 1.8). Almost all patients lived in Bangui (96%). Patients under 40 years of age were most commonly affected (55%). The majority of tumors were benign (55%). Ocular pain (24%), lacrimation (22%) and orbital swelling (16%) were the main symptoms. Risk factors were mainly age (23%), diabetes (22%), HIV infection (16%) and alcohol and tobacco use (37%). The most common treatments were surgical removal (68%) and enucleation (16%). Chemotherapy was combined with surgery in 37% of cases. Conclusion: Oculo-orbital tumors are frequent in our context. Their morpho-histological presentations are varied. A multidisciplinary approach is important for a good management.

The role of EZH2 in ocular diseases: a narrative review.

EZH2, acting as a catalytic subunit of PRC2 to catalyze lysine 27 in histone H3, induces the suppression of gene expression. EZH2 can regulate cell proliferation and differentiation of retinal progenitors, which are required for physiological retinal development. Meanwhile, an abnormal level of EZH2 has been observed in ocular tumors and other pathological tissues. This review summarizes the current knowledge on EZH2 in retinal development and ocular diseases, including inherited retinal diseases, ocular tumors, corneal injury, cataract, glaucoma, diabetic retinopathy and age-related retinal degeneration. We highlight the potential of targeting EZH2 as a precision therapeutic target in ocular diseases.

EZH2 is a protein that helps to regulate the activity of genes in cells. It works as a part of a complex called PRC2 to control a chemical group called lysine 27 in histone H3 and then inhibit the expression of genes. EZH2 is important for the normal development of the retina. Abnormal levels of EZH2 are associated with various eye diseases. This review summarizes the role of EZH2 in different ocular diseases and the potential mechanisms. Targeting EZH2 may be a novel way to treat or prevent ocular diseases.

Uveitic Granulomas Masquerading as Ocular Tumors.

Introduction: Solitary uveal lesions confer a diagnostic challenge to ophthalmologists. Uveitic lesions most abundantly appear amelanotic and commonly involve the choroid. Most amelanotic choroidal lesions are either neoplastic or inflammatory in origin. In our study, we aimed to describe six uveitic granuloma cases, which were referred to a tertiary ophthalmology center as intraocular tumors. Methods: Retrospective chart review of 6 patients (7 eyes) who had uveitic granulomas and were referred to a tertiary ophthalmology center as having intraocular tumors. Results: Mean age on presentation was 47 ± 12.5 years. One lesion was involving the ciliary body only, five lesions had pure choroidal involvement, and one had ciliochoroidal involvement. Mean visual acuity on presentation was 1.7 ± 0.75 (Snellen = 20/1,000) and ranged from 20/80 to light perception. Mean basal diameter of all lesions was 7.7 ± 1.8 mm. Three lesions had moderate echogenicity, two lesions were low to moderate echoic, and one lesion had moderate to high echogenicity on ultrasonography. Three lesions were associated with retinal detachments. Five eyes showed an early hypofluorescence with late hyperfluorescence. Leakage of fluorescein at borders was noticed in 3 lesions. Final diagnosis was presumed intraocular tuberculosis in 4 patients, probable ocular sarcoidosis in 1 patient, and idiopathic solitary uveitic granulomas in 1 patient. Upon treatment, the vision improved to 0.3 ± 0.27 (Snellen = 20/40) and ranged from 20/20 to 20/100 after 4.7 ± 2.9 years of follow-up. Conclusions: Uveitic granulomas can demonstrate features of ocular tumors. Proper uveitis management leads to a favorable visual outcome and ocular preservation.

Title: Clinico-pathological and survival profiles of orbito-ocular tumors in Enugu Nigeria. Is there an emerging trend?

BACKGROUND: Orbito-ocular tumors are rare, but they cause significant morbidity and mortality. There are reported variations in their pattern of presentation and frequency of occurrence. OBJECTIVE: To evaluate the occurrence, clinico-pathologic spectrum, and patterns of orbito-ocular neoplasms as well as the treatment and outcome profiles. METHODS: A 5-year retrospective analysis of consecutive patients treated for orbito-ocular tumors. We evaluated patterns of occurrence, clinic-pathological concordance, and outcome of treatment. Associations were evaluated with chi square and confidence interval. Data analysis was performed using SPSS for windows version 23 and inferences were judged using the 95% level of significance. RESULTS: Among 100 patients with orbito-ocular masses, 62 were histologically confirmed. The female to male ratio (F:M) was 1.0. Their ages ranged from 7 months to 93 years, mean = 33.4 ± 2.7 years. There was an age variation among tumor types. Patients with squamous cell carcinoma (SCC) had a mean age of 46.4 years, while for retinoblastoma the mean age was 3.09 years. All patients with retinoblastoma had proven macroscopic orbital extension. SCC was the most common tumor type (n = 19), however, among children, retinoblastoma (n = 11) was more common. Melanocytic nevus, sebaceous gland carcinoma, and adenocarcinoma of lacrimal gland (n = 6, n = 5, n = 5), respectively, among other tumors were treated. Concordance between clinical and histopathological diagnoses was obtained among 30 (48.3%) cases. 1-year and 3-year survival for retinoblastoma was 90% and 72.9%, respectively, and 78.9% and 68.4% for SCC. CONCLUSION: SCC is currently the most common orbito-ocular tumor in our setting.

Glabellar flap technique in oculoplastic surgery.

Facial skin defect reconstruction in medial-canthal area of the lids can be a challenge even when performed by a skilled surgeon. The excision of large tumors in this area leads to significant surgical defects that cannot be repaired by merely closing the wound. The glabellar area provides a source of redundant skin with similar characteristics to that of the medial-canthal lid area. The purpose show the possibility of the glabellar flap technique surgery in patients after tumor excision in the medial canthal area with the formation of a large surgical defect and especially those with defect under the medial canthal tendon. We selected 15 well-documented retrospective cases of patients operated over 2 years and followed up for a minimum of 36 months, who underwent surgery with a glabellar flap technique. Patients were operated with V-Y glabellar rotation, advancement, or combined transposition flap techniques. According to the defect's location, we divided the patients into three groups: upper, medial, and lower surgical defects. A satisfactory functional result was obtained in all the patients. In most of them, the cosmetic results were also good. No additional surgical procedures were required in any of the patients. Our experience showed excellent results with the glabellar flap technique in all three types of lesions in the medial canthal zone-upper, medial, and especially lower which until recently was thought to be inappropriate.

Individualized dosimetry in Ru-106 ophthalmic brachytherapy based on MRI-derived ocular anatomical parameters.

PURPOSE: To estimate ocular geometry-related inaccuracies of the dosimetric plan in Ru-106 ophthalmic brachytherapy. METHODS AND MATERIALS: Thirty patients with intraocular lesions were treated with brachytherapy using a Ru-106 plaque-shell of inner radius of 12 mm. Magnetic resonance imaging was employed to determine the external scleral radius at tumor site and the tumor margins. A mathematical model was developed to determine the distance between the external sclera and the internal surface of the plaque associated with the tangential application of the plaque on the treated eye. Differences in delivered dose to the tumor apex, sclera and tumor margins as derived by considering the default eye-globe of standard size (external sclera radius = 12 mm) against the individual-specific eye globe were determined. RESULTS: The radius of external sclera at the tumor site was found to range between 10.90 and 13.05 mm for the patient cohort studied. When the patient specific eye-globe/tumor geometry is not taken into account, the delivered dose was found to be overestimated by 8.1% ± 4.1% (max = 15.3%) at tumor apex, by 1.5% ± 2.8% (max = 5.7%) at anterior tumor margin, by 16.6% ± 7.5% (max = 36.4%) at posterior tumor margin and 8.1% ± 3.8% (max = 13.2%) at central sclera of eyes with lower than the default radius. The corresponding dose overestimations for eyes with higher than the default radius was 13.5% ± 4.3% (max = 22.3%), 1.5% ± 2.8% (max = 5.7%), 12.6% ± 4.5% (max = 20.0%), and 15.1% ± 5.0% (max = 24.4%). CONCLUSIONS: The proposed patient-specific approach for Ru-106 brachytherapy treatment planning may improve dosimetric accuracy. Individualized treatment planning dosimetry may prevent undertreatment of intraocular tumors especially for highly myopic or hyperopic eyes.

Ocular oncology service during the COVID-19 outbreak in Florence (Italy): Practical considerations for the management of patients.

The Coronavirus disease 2019 (COVID-19) outbreak has imposed the adoption of strategies to limit the risk of contagion for cancer patients without compromising their healthcare. As well as cancers of other sites, the treatment of certain ocular and periocular malignancies is considered non-deferrable and should proceed despite the pandemic. Delays in treatment of these patients may result in negative outcomes. Herein, we provide some practical considerations deriving from our experience at the Ocular Oncology Unit of Careggi University Hospital (Florence, Italy).