Occlusion of a mural type vein of Galen malformation in a 10-month-old boy with three Woven EndoBridge (WEB 17) and two coils.

We report the case of a 10-month-old boy with an enlarged head circumference and severe motor developmental delay. MRI showed a vein of Galen malformation (VGAM) with a heavily dilated median prosencephalic vein. Digital subtraction angiography confirmed a mural type VGAM with three feeding arteries arising from the posterior cerebral arteries. Due to the short length of the feeding arteries and the high flow, occlusion of the feeding vessels with detachable coils was not possible because of repeated coil dislocation into the dilated vein. Embolization of the three feeding vessels was then performed with a Woven EndoBridge single layer device (WEB SL17). In two arteries complete occlusion was accomplished with the WEB alone and in one artery additional deployment of two coils was necessary. Follow-up imaging at day 1 after treatment as well as 3 and 9 months after embolization showed persistent occlusion.

Specific immunohistochemical pattern of carbonic anhydrase IX is helpful for the diagnosis of CNS hemangioblastoma.

Hemangioblastomas are rare capillary-rich tumors predominantly found in the CNS. The histological appearance of these tumors varies across a broad spectrum. Several entities show considerable histomorphological similarities to hemangioblastomas. Therefore, morphological evaluation can be challenging. In this study, we evaluated the diagnostic utility of immunohistochemistry using antibodies against carbonic anhydrase IX and cytokeratin staining. Within our files, we identified 20 hemangioblastomas. A collection of 46 other tumors relevant to the differential diagnosis (12 pilocytic astrocytomas, 11 meningiomas, one pleomorphic xanthoastrocytoma, one angiomatous fibrous histiocytoma, 14 carcinoma metastases and seven gliomas grades II-IX) served as control. The pattern of strong, diffuse expression of carbonic anhydrase IX with membranous accentuation in combination with keratin negativity was considered diagnostic for hemangioblastomas. It was found in 18 out of 20 (90%) hemangioblastomas and in none of the control cases (P < 0.001). This resulted in a sensitivity of 90% and a specificity of 100%. The positive and negative predictive values were 100% and 96%, respectively. Carbonic anhydrase IX with cytokeratin is thus a highly sensitive and specific marker combination for hemangioblastomas. It is therefore very helpful in the diagnosis of these tumors and in their discrimination from other entities.

1 W of stable single-frequency output at 1.03 mum from a novel, monolithic, non-planar Yb:YAG ring laser operating at room temperature.

We demonstrate, for the first time to our knowledge, a longitudinally diode-pumped, monolithic ytterbium ion-doped YAG non-planar ring laser (NPRO). We achieved a continuous-wave (cw) single-frequency output power of 1 W with 45.0% slope efficiency and a beam quality factor of M(2)<1.1. In view of iodine frequency stabilization we have characterized the frequency tuning properties and have measured the relative intensity noise. Additionally, 6.1 mW second harmonic power at 515 nm was achieved using a periodically poled KTP crystal in a single-pass setup.