No abstract

Carotid-cavernous sinus fistula (CCF) is a syndrome in which arteriovenous shunts exist between the carotid artery and the cavernous sinus. These shunts vary widely in pathogenesis, angiogram, haemodynamics and treatment. Several systems of classification in terms of either haemodynamics, aetiology and/or pathogenesis have been reported, but they are not comprehensive. A more comprehensive and simpler nomenclature of classification is now required. Fifty seven cases of CCFs were analyzed and were classified according to their pathogenesis, angiography and treatment modalities. There were 11 traumatic CCFs with direct shunts (T-D group), and 2 traumatic CCFs with indirect shunts (T-I group). Spontaneous CCFs were divided into three groups. There were 37 spontaneous CCFs caused by dural arteriovenous shunts that were naturally classified as being indirect shunts (SD-I group). There were 5 spontaneous CCFs caused by suspected connective tissue disorders, such as fibromuscular dysplasia, Ehlers-Danlos syndrome etc.; these had direct shunts. Care was needed to avoid dissection of the artery or complications due to the fragility of connective tissue (SC-D group). There were 2 spontaneous CCFs caused by the rupture of an inflaclinoid aneurysm without any background of connective tissue disorder; these had direct shunts (SA-D group). By this system of grouping and use of abbreviations, each case of CCF can be clearly delineated in terms of its pathogenesis and selection for appropriate treatment.

A study of the thermodynamics of the liquid alloy systems Cu-Sn and Cu-Cr has been made with the combination of Knudsen cell and quadrupole mass spectrometer. From the data obtained, the activities in the liquid Cu-Sn and Cu-Cr systems, and the heats of mixing in the liquid Cu-Sn system were calculated.The activities and the heats of mixing for Cu-Sn alloys showed a good agreement with those of other investigators.The activity of Cr in Cu-Cr alloys showed a large positive deviation from Raoult's law. The liquidus line of the Cu-Cr system in the Cu-rich concentration range was determined from the break points of the ion current ratios in the mass spectrometric measurements as well as the differential thermal analysis.

Embolization of three surgically difficult cerebral aneurysms was performed using our newly developed non-adhesive embolic material, EVAL mixture (ethylene vinyl alcohol copolymer). Conventional embolic materials such as detachable balloons or microcoils were not used because of a large or irregular aneurysmal neck. After temporary occlusion of the parent artery with a superselective balloon catheter, the EVAL mixture was slowly injected through a microcatheter placed in the aneurysm or parent artery. The locations of the aneurysms were anterior communicating artery, basilar artery-posterior cerebral artery and basilar artery-anterior inferior cerebellar artery (BA-AICA). One aneurysmal occlusion and 2 parent artery occlusions were performed. Patients had no persistent deficits. The patient with the BA-AICA aneurysm associated with an arteriovenous malformation died of rupture of the residual AVM due to haemodynamic change 2 weeks after embolization. In selected and limited cases, embolization of surgically difficult cerebral aneurysms using EVAL mixture was more effective and safer than embolization using conventional embolic materials such as balloons and microcoils.

The static dielectric constant cg in Pbl-,Sn,Te (z = 0 to 0.4) single crystals is dctcrmined from a magnetoplasma reflection measurement between 4.2 and 100 K. At high temperat>ures E* increases with increasing temperature obeying a Curie law. The Cwie constant is practically unchanged for different alloy composition, and the inverse static dielectric constant a t 4.2 K decreases lineaarly with z, going to zero at alloy composition z = 0.35. At z = 0.40, a phase transition is observed at 20 K. The temperatnre dependence of cS is explained by anharmonic terms of lattice vibrations. La constant dielectrique cS dans les monocristals P b l -,Sn,Te (z = 0 to 0,4)-a 6tB determine par la mesure de reflexion de magneto-plasma B tempkratures entre 4.2 e t 100 K. A hautes tempkratures, cS augmente avec temperature par la loi de Curie. Les constantes de Curie dans alliage compositions differentes ne different pas de I'un l'autre, e t l/cS A 4.2 K diminuent en ligne directe avec z et vont A zero B alliage composition x = @,35. A z = 0,40; la transition de phase est trouve B 20 K. La dkpendance de temperature de eS est expliqui. par le terme de anharmonique de vibration de r6seau.