Brain parenchymal abnormalities were associated with DVAs in close to two thirds of the cases evaluated. These abnormalities are thought to occur secondarily, likely during post-natal life, as a result of chronic venous hypertension. Outflow obstruction, progressive thickening of the walls of the DVA and their morphological organization into a venous convergence zone are thought to contribute to the development of venous hypertension in DVA.

These results support side-specific accelerated WM loss in men, and may help our better understanding of changes in regional brain structures associated with pathological aging.

Persons in the IBNA study had clinical and neuropsychological features consistent with that of the general population. Their brain morphometric features may be used as normative references for patients with suspected neurodegenerative disorders.

We report on 36 cases of uveal melanoma treated at our center between March 1993 and September 1995. There were 16 men and 20 women, aged 57 ±11 years. The choroid was affected in 35 patients and the ciliary body in 1. The same preoperative and follow-up protocol was adopted for all cases. The procedure included fixation and positioning of the eye with a retrobulbar injection of long-lasting anesthetic and two extraocular muscle sutures, application of the frame, computed tomography scan localization, dose planning and treatment with the Gamma Knife. The patients were divided into three groups. Group A: 10 patients with a follow-up of 24 ± 4 months, treated with a high dose (surface dose 58 ± 9 Gy, maximum dose 81 ± 15 Gy, mean dose 66 ±11 Gy). Group B: 9 patients with a follow-up of 16 ± 2 months, treated with a lower dose (surface dose 41 ± 3 Gy, maximum dose 76 ± 10 Gy, mean dose 53 ± 11 Gy). Group C: 17 patients with a follow-up of 6 ± 3 months, treated with a lower dose (surface dose 42 ± 3 Gy, maximum dose 72 ±16 Gy, mean dose: 54 ± 6 Gy). In group A, we observed marked tumor regression in 9 cases, tumor recurrence in 1 case and severe complications in 5 cases (neovascular glacuoma and/ or radiation retinopathy and/or radiation optic neuropathy). In group B, significant local control of the tumor was obtained with minor complications (cotton wool spots, hard exudates, intraretinal hemorrhages). In group C, to date we have observed a regression of the tumor in 7 cases and 1 severe complication (neovascular glaucoma). Our data show that uveal melanomas may be adequately controlled by a high radiosurgical dosage (50–70 Gy), though there are significant side effects. Comparable levels of local tumor control may be obtainable using lower doses (40–45 Gy) which would hopefully reduce the rate of complications. However, a longer follow-up is needed for further validation of these results.

Twelve cases of uveal melanoma (T₃N₀M₀:11 patients, T₄N₀M₀:1 patient) treated with Gamma Knife stereotactic radiosurgery are reported. Our protocol includes preoperative ocular and systemic assessments with complete ocular examination, ophthalmoscopy, fundus photography, fluorangiography, standardized echography, CT and MRI, chest X-rays, liver echography and blood tests. The follow-up program is mainly based on echographic evaluation of tumor thickness and size. The procedures include fixation of the eye, application of the stereotactic Leksell frame G, CT/MRI localization of the melanoma, dose planning and treatment with the Gamma Knife (B type). A mean surface dose of 55 ± 10 Gy was administered at the 60–90% isodose curve using 4- to 14-mm collimators and a number of shots ranging from 1 to 6. A significant reduction (10–41 %) in echographic thickness of the tumor was shown in 6 cases with a follow-up of 3–12 months. In 4 patients, the tumor size was still unchanged after 1–10 months. The single high-dose radiation delivered to the target and the high spatial accuracy are the main advantages of stereotactic radiosurgery for the treatment of posterior uveal melanomas. A longer follow-up is needed to further validate this new application of Gamma Knife radiosurgery.