Effect of intravitreal C3F8 gas in patients with vitreomacular traction: A retrospective case series.

BACKGROUND: We aimed to assess the efficacy of a single intravitreal perfluoropropane (C3F8) gas injection for the treatment of vitreomacular traction with or without a macular hole. METHODS: In this retrospective case series, seven eyes of six patients with symptomatic vitreomacular traction documented on optical coherence tomography, one with a macular hole additionally, received a single intravitreal C3F8 gas injection of up to 0.3 ml. The primary endpoint was vitreomacular traction release at 1 month after injection. Secondary endpoints included resolution of vitreomacular adhesion within 6 months, nonsurgical closure of macular holes, and change in central foveal thickness and best-corrected visual acuity. RESULTS: Overall, on optical coherence tomography, six of seven eyes (85.7%) had release of vitreomacular traction during the entire study duration: three within 1 month of injection and the other three within 6 months. Of the latter group, two of the three eyes showed a concurrent epiretinal membrane and one concurrent diabetic retino- and maculopathy. The patient with a macular hole had resolution of vitreomacular traction within 1 month but had to undergo vitrectomy because of nonclosure of the macular hole. Associated adverse events were macular edema with a consequent lamellar hole after injection in one patient, and another patient developed retinal detachment. CONCLUSION: Intravitreal C3F8gas injection is an inexpensive and promising minimally invasive option for the treatment of symptomatic and persistent vitreomacular traction with or without a macular hole. Further larger studies, especially comparing C3F8 gas injection with other treatment options, are needed.

A Unifying Concept of Uveal Pigment Cell Distribution and Dissemination Based on an Animal Model: Insights into Ocular Melanogenesis.

Pigmented cells are derived from neural crest cells, which migrate along the peripheral nerve sheets into their specific final region. During their migration, cells progressively acquire pigment-producing capabilities, maturation, and the shape of melanocytes. These insights, along with specific clinical characteristics of melanocytic nevi, have led to new concepts of cutaneous, periocular, and iris nevogenesis. To further elucidate the specific ocular embryogenic melanoblast distribution and dissemination - that could explain the distinct distribution of uveal melanocytic neoplasms - we investigated the ocular pigmentation of dogs affected by a specific mutation called Merle, which results in either pigment- (wild type) or non-pigment- (mutated type) producing cells. Based on our observations, we propose a unifying concept of uveal pigment cell distribution and dissemination, which postulates melanoblast migration and maturation following the trigeminal V1 branch and, later, their entrance into the eye along the ciliary nerves and their finest iris branches. Our concept provides an explanation not only for the specific distribution of ocular melanocytic lesions, including uveal and iris nevi, but also for the different locations depending on the metastatic potential of the ocular melanoma. Though speculative, the higher metastatic potential of posterior uveal melanomas compared to iris melanomas may be related to a less differentiated stage in the maturation of migrating melanocytes in the posterior segment compared to the anterior segment of the eye. However, there is a need of further studies focusing on cell differentiation markers of melanocytes at different locations in the eye.

Mutations in GNA11 in uveal melanoma.

BACKGROUND: Uveal melanoma is the most common intraocular cancer. There are no effective therapies for metastatic disease. Mutations in GNAQ, the gene encoding an alpha subunit of heterotrimeric G proteins, are found in 40% of uveal melanomas. METHODS: We sequenced exon 5 of GNAQ and GNA11, a paralogue of GNAQ, in 713 melanocytic neoplasms of different types (186 uveal melanomas, 139 blue nevi, 106 other nevi, and 282 other melanomas). We sequenced exon 4 of GNAQ and GNA11 in 453 of these samples and in all coding exons of GNAQ and GNA11 in 97 uveal melanomas and 45 blue nevi. RESULTS: We found somatic mutations in exon 5 (affecting Q209) and in exon 4 (affecting R183) in both GNA11 and GNAQ, in a mutually exclusive pattern. Mutations affecting Q209 in GNA11 were present in 7% of blue nevi, 32% of primary uveal melanomas, and 57% of uveal melanoma metastases. In contrast, we observed Q209 mutations in GNAQ in 55% of blue nevi, 45% of uveal melanomas, and 22% of uveal melanoma metastases. Mutations affecting R183 in either GNAQ or GNA11 were less prevalent (2% of blue nevi and 6% of uveal melanomas) than the Q209 mutations. Mutations in GNA11 induced spontaneously metastasizing tumors in a mouse model and activated the mitogen-activated protein kinase pathway. CONCLUSIONS: Of the uveal melanomas we analyzed, 83% had somatic mutations in GNAQ or GNA11. Constitutive activation of the pathway involving these two genes appears to be a major contributor to the development of uveal melanoma. (Funded by the National Institutes of Health and others.).

Eye Tumors in Childhood as First Sign of Tumor Predisposition Syndromes: Insights from an Observational Study Conducted in Germany and Austria.

Retinoblastoma and other eye tumors in childhood are rare diseases. Many eye tumors are the first signs of a genetic tumor predisposition syndrome and the affected children carry a higher risk of developing other cancers later in life. Clinical and genetic data of all children with eye tumors diagnosed between 2013-2018 in Germany and Austria were collected in a multicenter prospective observational study. In five years, 300 children were recruited into the study: 287 with retinoblastoma, 7 uveal melanoma, 3 ciliary body medulloepithelioma, 2 retinal astrocytoma, 1 meningioma of the optic nerve extending into the eye. Heritable retinoblastoma was diagnosed in 44% of children with retinoblastoma. One child with meningioma of the optic nerve extending into the eye was diagnosed with neurofibromatosis 2. No pathogenic constitutional variant in DICER1 was detected in a child with medulloepithelioma while two children did not receive genetic analysis. Because of the known association with tumor predisposition syndromes, genetic counseling should be offered to all children with eye tumors. Children with a genetic predisposition to cancer should receive a tailored surveillance including detailed history, physical examinations and, if indicated, imaging to screen for other cancer. Early detection of cancers may reduce mortality.

Surgical smoke management for minimally invasive (micro)endoscopy: an experimental study.

BACKGROUND: The aim of this study was to investigate the use of surgical smoke-producing procedures such as laser ablation or electrosurgery in minimally invasive microendoscopic procedures. This study proposes a technical solution to efficiently remove surgical smoke from very small endoscopic cavities using microports as small as 20 G (0.9 mm) in diameter. METHODS: The experimental laboratory study used small, rigid, transparent plastic cavity models connected with tubes and pressure sensors to establish an endoscopic in vitro laboratory model. A Kalium-Titanyl-Phosphate (KTP) laser with a 0.5-mm fiber optic probe was used to produce smoke from bovine scleral tissue in the cavity. Endoscopic gas insufflation into the model was generated by pressurized air and a microvalve. A laboratory vacuum pump provided smoke and gas suction via a microvalve. A self-built control and steering system was utilized to control intracavital pressure during experimental insufflation and suction. RESULTS: Problems related to smoke-generating processes, such as laser vaporization or electrocautery, in small closed cavities were first analyzed. A theoretical and mechatronic laboratory model was established and tested. Intracavital pressure and gas flow were measured first without and then with smoke generation. A new construction design for the suction tube was proposed due to rapid obstruction by smoke particles. CONCLUSIONS: Surgical smoke evacuation from endoscopic cavities that are as small as 2 cm in diameter via minimally invasive ports as small as 20 G (0.9 mm) in diameter may be safe and efficient if sufficient gas exchange is provided during smoke generation by laser or electrosurgical instruments. However, maintaining a low and constant pressure in the cavity during gas exchange and adopting a special construction design for the suction tube are essential to provide an excellent view during the surgical maneuver and to minimize potential toxic side effects of the smoke.

Tumor parameters predict the risk of side effects after ruthenium-106 plaque brachytherapy of uveal melanomas.

BACKGROUND: To report on radiation-related side effects and complications after ruthenium-106 plaque brachytherapy of uveal melanomas. METHODS: Medical records of 143 eyes with uveal melanoma, treated by ruthenium-106 brachytherapy between 1997 and 2012 at a single center, were analyzed. We evaluated the occurrence of radiation-related side effects on the anterior and posterior segment of the eye. The influence of patient, tumor and treatment parameters on outcome was analyzed by multivariate time to event analysis considering competing risks. RESULTS: The median overall follow-up was 37.9 months. After treatment, the estimated risk at 12, 24 and 48 months for developing anterior segment complications was 25.3%, 37.5% and 50.3% for cataract formation and 5.4%, 6.4% and 8.1% for secondary glaucoma, respectively. The estimated risk for the occurrence of posterior segment complications 12, 24 and 48 months after treatment was 3.1%, 6.7% and 18.3% for radiation retinopathy, 18.3%, 27.1% and 42.6% for radiation maculopathy and 16.5%, 21.0% and 32.8% for radiation neuropathy, respectively. The risk of an increase in retinal detachment after treatment was 14.7%, 14.7% and 17.4% at 12, 24 and 48 months, respectively. The risk of vitreous hemorrhage occurring after treatment was 6.2%, 8.1% and 12.7%, and the risk of tumor vasculopathy was 15.4%, 17.4% and 19.0%. Scleral necrosis was observed in one patient. CONCLUSION: Radiation-related side effects and complications are common among patients treated with ruthenium brachytherapy for uveal melanoma. However, the risk for those largely depends on individual tumor parameters. Before treatment, patients should be informed of their specific risks to develop various side effects. Patient information before treatment should cover not only general information about the treatment and possible complications and side effects but should also give details on the specific risks of the patient in her individual situation. This also includes elucidating the patient's individual resources and expectations and her willingness for long-term regular follow-up examinations and secondary adjunct treatments.

Iris Freckles a Potential Biomarker for Chronic Sun Damage.

Purpose: To investigate the role of sunlight exposure in iris freckles formation. Methods: We prospectively examined volunteers attending a skin cancer screening program conducted by ophthalmologists and dermatologists. Frequency and topographical variability of iris freckles were noted and associated with behavioral and dermatologic characteristics indicating high sun exposure. Results: Six hundred thirty-two participants (n = 360; 57% female) were examined. Mean age of all participants was 38.4 ± 18.4 years (range, 4-84 years). Of all individuals, 76.1% (n = 481) exhibited at least one iris freckle. Most freckles were observed in the inferior temporal quadrant. The presence of iris freckles was associated with higher age (participants with iris freckles: 41.8 ± 16.8 years versus participants without iris freckles: 27.6 ± 19.2 years), a high number of sunburns during lifetime (>10: 31% vs. 19%), sunlight-damaged skin (26% vs. 11%), presence of actinic lentigines (72% vs. 45%), and a high total nevus body count (>10; 78% vs. 67%). Conclusions: The association of iris freckles, behavioral factors, and dermatologic findings, as well as the topographical distribution, indicate that sunlight exposure may trigger the formation of iris freckles. The evaluation of iris freckles offers an easily accessible potential biomarker, which might be helpful in indicating sun damage on the skin associated with cutaneous malignancies. Furthermore, the evaluation of iris freckles could also be helpful in understanding the role of sunlight in several ophthalmologic diseases.

Vitreous hyper-reflective dots in pseudophakic cystoid macular edema assessed with optical coherence tomography.

PURPOSE: This study compares the presence of vitreous hyper-reflective dots (VHDs) detected with optical coherence tomography (OCT) between eyes with pseudophakic cystoid macular edema (CME) and those with no CME after cataract surgery. In addition, we evaluated the impact of VHDs on the responsiveness of pseudophakic CME to cortisone treatment. SETTING: Department of Ophthalmology, Medical University of Graz, Austria. DESIGN: Retrospective, monocenter case-controlled study. METHODS: Inclusion criteria for the study group and the control group were CME and no CME within 12 weeks following uneventful phacoemulsification in otherwise healthy eyes, respectively. VHDs (number and size) and the macular thickness were assessed with OCT. Furthermore, the number of peribulbar or intravitreal steroid injections was assessed. RESULTS: A total of 284 eyes from 267 patients were analyzed, among which 119 met the inclusion criteria for the study (n = 63) and the control group (n = 56). VHDs were observed in 54 (85.7%) study eyes and 21 (37.5%, p = 0.013) control eyes. The number of VHDs was 3.9±3.4 in the study group and 0.7±1 in the control group (p<0.001). The size of the VHDs was 33.5±9.1 µm and 36.6±17.9 µm in the study and control groups, respectively (p = 0.978). Overall, the number of VHDs correlated with central subfield thickness (r = 0.584, p<0.001), cube volume (r = 0.525, p<0.001), and postoperative best-corrected visual acuity (BCVA) (r = -0.563, p<0.001). The number of VHDs did not correlate with the frequency of peribulbar or intravitreal steroid injections. CONCLUSION: VHDs occurred more often in eyes with CME than in eyes without CME following cataract surgery. In addition, the number of VHDs had an impact on the extent of macular thickening and subsequently postoperative BCVA. No correlation was found between the number of VHDs and the frequency of required peribulbar or intravitreal steroid injections.

Circadian macular volume changes in the healthy human choroid.

PURPOSE: To investigate a potential circadian fluctuation of the choroidal volume in healthy adults by enhanced depth imaging (EDI) via spectral-domain optical coherence tomography (SD OCT). DESIGN: Prospective observational case series. METHODS: Thirty healthy eyes of 15 healthy subjects with a median age of 26 years (range 22-55) underwent EDI SD OCT scans for macular choroidal volume measurement every 3 hours within a 24-hour period at a single tertiary center. The mean ocular perfusion pressure was calculated for each eye at each of the 8 time points as 2/3(mean arterial pressure-intraocular pressure [IOP]). The circadian fluctuation of the macular choroidal volume as well as the association with axial length, mean ocular perfusion pressure, or IOP was assessed using a linear mixed model. RESULTS: Macular choroidal volume showed a significant circadian fluctuation (P < .05) and was lowest at midday (mean ± SD, 10.14 ± 2.62 mm(3)) and highest at 3 AM (mean ± SD, 10.66 ± 2.70 mm(3)). Of all factors tested, only mean ocular perfusion pressure showed a significant association with macular choroidal volume fluctuation (P = .016). CONCLUSIONS: Macular choroidal volume shows a significant circadian pattern with higher values at night and lower values during the day in young adults. Besides time, mean ocular perfusion pressure is significantly associated with this fluctuation.

Ruthenium-106 plaque brachytherapy for uveal melanoma.

BACKGROUND: To report on local tumour control, eye preservation and visual outcome after ruthenium-106 brachytherapy for uveal melanoma. METHODS: Medical records of 143 eyes with uveal melanoma, treated by ruthenium-106 brachytherapy between 1997 and 2012 at one single centre, were included. Primary outcome measures were local tumour control, eye preservation and visual outcome. The influence of patient, tumour and treatment parameters on outcome was analysed by time to event analysis and competing risk regression. RESULTS: The median overall follow-up was 37.9 months. Tumour control: recurrent tumour growth was observed in 17 patients. The estimated local tumour recurrence rate at 12, 24 and 48 months after irradiation was 3%, 8.4% and 14.7%, respectively. The only significant risk factors for tumour recurrence were age (p=0.046) and reduced initial visual acuity (VA, p=0.045). No significant difference could be shown for tumour size or tumour category (T1-T2 vs T3-T4), and for any other tumour or treatment parameters (including combined transpupillary thermo-therapy (TTT)).Eye preservation: The likelihood of keeping the eye 12, 24 and 48 months after irradiation was 97.7%, 94.7% and 91.8%, respectively. Most significant risk factors for secondary enucleation were initial VA (p<0.001), tumour height (p=0.002) and tumour category (p=0.015). VISION: The chances of keeping VA of 20/200 or better at 1, 2 and 5 years after treatment were 86.4%, 80.8% and 61.7%, respectively. Patients receiving sandwich-TTT showed significantly worse visual outcomes. CONCLUSIONS: Ruthenium-106 brachytherapy appears to be a useful treatment regarding tumour control, eye preservation and visual function. Adjunct sandwich therapy resulted in worse visual outcome.

New insights into oculodermal nevogenesis and proposal for a new iris nevus classification.

BACKGROUND/AIMS: To gain more knowledge about presence and dermatological associations of iris nevi as well as possible pathways involved in the formation of iris nevi. METHODS: We conducted a prospective, interdisciplinary observational study. Presence, morphology, topography of iris and cutaneous nevi as well as factors indicating sun-exposure were noted. RESULTS: A total of 632 participants including 360 (57%) women were examined. Of those, 26 subjects revealed 27 iris nevi. According to the current classification, all iris nevi were judged as solitary with the majority of them (n=20; 74%) located in the lower quadrants. In six (22.2%) cases we noted a peculiar 'incomplete sectoral pattern'; these nevi were located close to the pupil, were larger and had a more elongated, triangular shape compared with those located distant from the pupil, which appeared smaller and more roundish. Notably, five of these six peculiar (incomplete sectoral) iris nevi were located on the upper half of the iris. CONCLUSIONS: Based on our findings we propose classifying iris nevi into sectoral, incomplete sectoral and solitary subtypes. Additionally, we set up a hypothetic concept of oculodermal nevogenesis suggesting a time-dependent embryogenic alteration affecting the normal melanocyte location, migration and maturation along peripheral nerve sheets. Our new concept explains well the morphology and extension of benign melanocytic proliferations in the ocular region as well as their relation to uveal melanoma.

A Systematic Review and Meta-Analysis on the Safety of Vascular Endothelial Growth Factor (VEGF) Inhibitors for the Treatment of Retinopathy of Prematurity.

INTRODUCTION: Laser photocoagulation is the current gold standard treatment for proliferative retinopathy of prematurity (ROP). However, it permanently reduces the visual field and might induce myopia. Vascular endothelial growth factor (VEGF) inhibitors for the treatment of ROP may enable continuing vascularization of the retina, potentially allowing the preservation of the visual field. However, for their use in infants concern remains. This meta-analysis explores the safety of VEGF inhibitors. METHODS: The Ovid Interface was used to perform a systematic review of the literature in the databases PubMed, EMBASE and the Cochrane Library. RESULTS: This meta-analysis included 24 original reports (including 1.457 eyes) on VEGF inhibitor treatment for ROP. The trials were solely observational except for one randomized and two case-control studies. We estimated a 6-month risk of retreatment per eye of 2.8%, and a 6-month risk of ocular complication without the need of retreatment of 1.6% per eye. Systemic complications were only reported as isolated incidents. DISCUSSION: VEGF inhibitors seem to be associated with low recurrence rates and ocular complication rates. They may have the benefit of potentially allowing the preservation of visual field and lower rates of myopia. Due to the lack of data, the risk of systemic side effects cannot be assessed.

Opacification of a silicone intraocular lens caused by calcium deposits on the optic.

We describe opacification of a plate-haptic silicone intraocular lens (IOL) caused by calcification in a diabetic patient with asteroid hyalosis. The IOL was explanted 48 months after uneventful phacoemulsification because opacification of the posterior surface was causing significant visual disturbance. Light and scanning electron microscopy and x-ray spectrometry of the explanted IOL showed the opacification consisted mainly of calcium and phosphate, presumably hydroxyapatite, in the form of precipitations on the posterior surface of the optic.

Ocular trauma scores in paediatric open globe injuries.

BACKGROUND/AIMS: To assess the predictive value and the applicability of Ocular Trauma Score (OTS) for paediatric injuries. METHODS: Retrospective case series of 71 open globe injuries in children less than 18 years of age with a minimum follow-up period of 1 year. The variables of the OTS, the Paediatric Penetrating OTS (POTS), lens injuries and anterior versus posterior segment injuries were analysed for their predictive values in terms of visual outcome. The applicability and the predictive values of OTS and POTS as a whole were then evaluated. RESULTS: Initial visual acuities, retinal detachments, wound locations (p<0.001 each), lens injuries (p=0.001), posterior segment injuries (p=0.002), traumatic cataracts (p=0.010), hyphaema (p=0.011) and vitreous haemorrhages (p=0.026) had significant impacts on visual outcome. The application of OTS proved difficult, as the presence of a mild degree of a relative afferent pupillary defect (RAPD) could not accurately be evaluated in all of our patients. Calculating the OTS without evaluation of RAPD renders it easily applicable for the initial examinations while remaining significantly prognostic (p<0.001). The predictions of the POTS correlated with the actual final visual acuities (p<0.001), but several POTS variables (ie, iris prolapse, age, organic injuries and delay of surgery >48 h) had only limited impacts on visual outcome. CONCLUSIONS: The OTS has a high predictive value for visual outcome after open globe injuries in children, even without evaluation of RAPD.

Local tumour control and eye preservation after gamma-knife radiosurgery of choroidal melanomas.

BACKGROUND/AIMS: To report on local tumour control and eye preservation after gamma knife radiosurgery (GK-RS) to treat choroidal melanomas. METHODS: A total of 189 patients with choroidal melanoma were treated with GK-RS, with treatment doses between 25 and 80 Grays. The main outcome measures of our retrospective analysis were local tumour control, time to recurrence, eye retention rate and the reason for and time to secondary enucleation. Patient-associated, tumour-associated and treatment-associated parameters were evaluated as potential risk factors. RESULTS: Local tumour control was achieved in 94.4% of patients. The estimated tumour control rates were 97.6% at 1 year, 94.2% at 5 years and 92.4% at 10 years after treatment. Recurrence was observed between 3.1 months and 60.7 months post-treatment (median: 13.5 months). Advanced tumour stage (Tumour, Node, Metastasis (TNM) 3-4) was the most important risk factor for recurrence (Fine-Gray model; subhazard ratio, SHR: 3.3; p=0.079). The treatment dose was not related to tumour recurrence. The eye preservation rate was 81.6% at 5 years after treatment, remaining stable thereafter. Twenty-five eyes (14.1%) had to be enucleated at between 17 days and 68.0 months (median: 13.9 months) after GK-RS, and advanced tumour stage (Cox model; p=0.005), treatment dose (p=0.048), pretreatment visual acuity (p=0.016), and retinal detachment (p=0.027) were risk factors for requiring enucleation. CONCLUSIONS: GK-RS achieved a high tumour control rate, comparable to linear accelerator-based radiotherapy. Advanced TNM stage was a predictive risk factor for tumour recurrence and for secondary enucleation after GK-RS. Lower treatment doses were unrelated to tumour recurrence, although they were associated with an improved eye retention rate.

Visual acuity after Gamma-Knife radiosurgery of choroidal melanomas.

BACKGROUND/AIMS: To report on conservation of visual acuity after Gamma-Knife radiosurgery of choroidal melanoma. METHODS: A total of 189 patients with choroidal melanoma were treated with Gamma-Knife stereotactic single-fraction radiosurgery at a single institution between June 1992 and May 2010. The main outcome measure of our retrospective analysis was conservation of pretreatment visual acuity of 20/40 or better, 20/200 or better and counting fingers (CF) or better, over time of follow-up. Patient, tumour and treatment parameters were evaluated as potential risk factors for visual loss. RESULTS: Five years after treatment, the actuarial probability of keeping visual acuity better than 20/40, 20/200 and CF was 13%, 14% and 36%, respectively. The majority of patients (84.7%) encountered a deterioration of vision after treatment. The most important risk factors for visual loss were tumour height, longest basal diameter, distance to the optic disk and/or foveola, and retinal detachment before treatment. Treatment dose, and patient characteristics (age, sex, concurrent systemic diseases) were less important. Local tumour control rate was 94.4% after a median follow-up of 39.5 months. CONCLUSIONS: Visual outcome after single-fraction Gamma-Knife radiotherapy is comparable with linear accelerator (LINAC) based fractionated stereotactic radiotherapy, inferior to proton beam radiotherapy, and depends primarily on tumour size, location and pre-existing retinal detachment.

Influence of single-fraction Gamma-Knife radiosurgery on ocular surface and tear function in choroidal melanoma patients.

AIM: To evaluate ocular surface and tear function in patients with choroidal melanoma treated with single-fraction radiosurgery. METHODS: 36 patients (median age 62 years; range 26-84 years) were enrolled between 2001 and 2006 at a single institution. They were treated with the Leksell Gamma Knife in one fraction with a median dose of 30 Gy (range 25-35 Gy). In both eyes of all patients treated subjective symptom score (visual analogue scale) was evaluated, central corneal sensitivity testing, Schirmer test without local anaesthesia, and corneal and conjunctival staining were performed before therapy and 3, 6, 12, 24 and 36 months thereafter. The respective untreated fellow eye served as control. RESULTS: Three months after radiosurgery, the subjective dry eye symptom score and lissamine green staining score of the ocular surface were significantly higher in the treated eyes compared with the fellow eyes (p<0.001, p=0.028, respectively). After 12 months, a significant difference between the treated and the fellow eyes in corneal sensitivity (p=0.041) and corneal fluorescein staining (p=0.002) was found when compared with pretreatment values. After 24 months Schirmer test values without local anaesthesia were significantly reduced in the treated eyes vis-à-vis untreated fellow eyes and pretreatment values (p=0.004). The dose applied to the lacrimal gland was significantly correlated to ocular surface staining scores (p=0.001) and Schirmer test values (p=0.026) at 24 months after irradiation. CONCLUSIONS: Stereotactic single-fraction Gamma-Knife radiotherapy of choroidal melanoma with a median dose of 30 Gy significantly affected ocular surface and tear function and increased dry eye symptoms and signs.