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Background: To report the clinical features and outcomes of iris melanomas treated by proton beam therapy., Materials and Methods: A retrospective study was conducted at the Croix-Rousse University Hospital of Lyon, Department of Ophthalmology, in 36 patients treated by proton beam therapy for presumed (n = 29) and confirmed (n = 7) iris melanomas between July 1997 and October 2010. Ciliary body melanomas with iris involvement were excluded. The patients' mean age was 54.4 years (range, 22-82 years). The average tumor diameter was 3.8 mm (range, 2.5-8.0). The iridocorneal angle was invaded by the tumor in 47% of cases (n = 17), the ciliary body in 17% of cases (n = 6), and the sclera in 3% (n = 1). Raised intraocular pressure was present before treatment in 11.1 % of cases (n = 4). Tumor biopsy was performed in 19% of cases (n = 7). Four patients had undergone an initial incomplete surgical excision of tumor before radiotherapy. Surgical preparation of the eye with tantalum ring positioning had been performed in all cases 3-4 weeks before irradiation. The prescribed dose was 60 Cobalt Gray Equivalent (CGE) of proton beam radiotherapy delivered in four fractions on four consecutive days., Results: The median follow-up was 50 months (mean 60.5, range 15-136). One patient (2.7%) was lost to follow-up. None of the patients showed tumor progression, local recurrence, or metastasis. None of the patients required secondary enucleation. Cataract was developed in 62% of patients, glaucoma in two cases (6%) after irradiation, and hyphema with the aggravation of pre-existing glaucoma in one patient. No patients developed neovascular glaucoma., Conclusions: Proton beam therapy appears to be the treatment of choice for the conservative treatment of iris melanomas with excellent tumor control and an acceptable rate of complications. Longer follow-up studies on a larger series is necessary to consolidate these results.

Objective: Drug resistant epilepsy associated with hypothalamic hamartoma (HH) can be cured by microsurgical resection of the lesion. Morbidity and mortality risks of microsurgery in this area are significant. Gamma Knife Surgery's (GKS) reduced invasivity seems to be well adapted. In view of the severity of the disease and risks of surgical resection it is crucial to evaluate GKS for this indication. A first retrospective study has shown a very good safety and efficacy level but for a more reliable evaluation a prospective study would be required., Methods: Between Oct 1999 and July 2002, 30 patients with HH and associated severe epilepsy were included. Seizure semiology (video EEG) and frequency, behavioural disturbances, neuropsychological performance, endocrinological status, sleep electroclinical abnormalities, MR imaging, and visual function were systematically evaluated before and after GKS (6, 12, 18, 24, 36 months). Twenty patients had experienced precocious puberty at a median age of 3,7 (0-9). Range of maximum diameter was from 7,5 to 23 mm with only 3 larger than 18 mm. The median marginal dose was 17 gy (14-20)., Results: Sufficient follow up for final evaluation is not yet available. Only 6 patients have a follow-up of more than 12 months and 19 more than 6 months. However a lot of very dramatic changes did occur during that period in this group. Among the 19 patients with more than 6 months of follow-up, a lot had already experienced an increase of gelastic seizures around 3 months (3), an improvement in their seizure rate (18), behaviour (9), sleep (3), and EEG background activity (3), a cessation of partial complex seizures (7). No complications have occurred till now except one patient experiencing at 5 months a hyperthermia without infection and concomitant increase of gelastic seizures both ceasing suddenly and spontaneously after 15 days., Conclusion: Our first results indicate that GKS is as effective as microsurgical resection and very much safer. GKS also allows to avoid the vascular risk related to radiofrequency lesioning or stimulation. The disadvantage of radiosurgery is its delayed action. Longer follow-up is mandatory for a serious evaluation of the role of GKS. Results are faster and more complete in patients with smaller lesions inside the 3rd ventricle (grade II). The early effect on subclinical discharges turns out to play a major role in the dramatic improvement of sleep quality, behaviour, developmental acceleration at school.

Introduction: The more classical approach for Epilepsy surgery is the removal of the epileptogenic zone (ZE). We present a critical review of information in favor of a possible non-destructive effect of radiosurgery in epilepsy surgery., Material: Clinical material of patients with epilepsies related to a lesion in highly functional areas subjected to radiosurgery with relief of the seizures and no functional worsening is available. We applied direct treatment of the EZ with good efficacy in the absence of destructive aspects on the MR and no functional deterioration (e.g. hypothalamic hamartomas). Experimental studies have shown biochemical differential effect of radiosurgery on the striatum, glial cell elimination, stem cell migration toward the target area, sprouting,... Plasticity phenomenon are induced by radiosurgery when using non necrotizing dosemetry., Discussion: There is clinical and experimental evidence of Gamma Knife capability to induce modulation in the neural system. Detailed mechanism of this modulation and dosemetric parameters enabling to induce such plasticity with no necrosis are still unknown. Subpial transection turning out actually to be quite disappointing, there is a specific rationale to test radiosurgery capability to treat EZ cortex while preserving the underlying function of this cortex when the functional risk for cortectomy is too high.