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The thermal behaviour of strontium hydroxide octahydrate was studied by thermal analysis, an X-ray diffraction technique and optical microscopy. Up to 210 ~ this compound transforms to the hexahydrate and then to the monohydrate. Anhydrous strontium hydroxide crystallizes in the tetragonal system and a polymorphous transformation may occur at 480 ~ . From 530 ~ on it decomposes in three stages. Amorphous strontium oxide is obtained at 700 ~ .When ceramic bodies containing free strontium oxide are hydrated, strontium hydroxide results, and this causes their deterioration.According to literature data two strontium hydroxide compounds exist in the hydrated state: the octahydrate and the monohydrate.Strontium hydroxide octahydrate -Sr(OH)~ 9 8 H20 -may be obtained by crystallization from an aqueous strontium hydroxide solution [1], or by precipitating strontium hydroxide from the nitrate with NaOH and washing the precipitate with cold ethyl alcohol [2]. It crystallizes in the tetragonal system with the unit cell constants a = 9 A and c = 11.58/k From a study of the solubility of St(OH)2 in water, Latimer [5] has shown that the octahydrate becomes metastable at a temperature of 80 ~ The existence of strontium hydroxide monohydrate -Sr(OH)2 9 H20 -is reported by Reinders and Klinkenberg [6], who consider that it is formed in solution at 87.7 ~ The monohydrate was also obtained by drying the octahydrate in vacuum or in a current of hydrogen at 45-50 ~ [7].

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In this paper, synthesis of hydroxyapatite (HAp) in the absence or presence of 1.05 wt% magnesium oxide, as sintering additive, by heating in a microwave oven was studied. For this purpose, CaSO(4).2H(2)O, Ca(OH)(2), Mg(OH)(2) and (NH(4))(2)HPO(4) were used as raw materials. The total chemical reactions for all the studied compositions were observed after a 3 h microwave treatment. In case of pure hydroxyapatite, a powder with needle-like grains results. In the presence of Mg(OH)(2), the (Mg, Ca(2)).O.(HPO(4))(2).H(2)O hydrated phosphate is formed besides hydroxyapatite. Pure hydroxyapatite, thermally treated at 1,200 degrees C, mostly transforms in beta-Ca(3)P(2)O(8). By adding MgO into the precursor mixture, hydroxyapatite was stabilised, and found in a much greater proportion at 1,200 degrees C. After the thermal treatment, the hydroxyapatite, analysed by electronic microscopy, shows a prismatic morphology originating in its initial state.

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Micropulse transscleral diode laser cyclophotocoagulation (mTSCPC) is an established method of treatment for refractory glaucoma. This study evaluates the efficacy and safety of subconjunctival bevacizumab associated with mTSCPC versus mTSCPC alone. A number of six patients with neovascular glaucoma were treated with mTSCPC, three patients being treated with mTSCPC alone and three patients being treated with combination of mTSCPC and subconjunctival bevacizumab. The intraocular pressure (IOP), visual acuity, number of medications were monitored for 6 months. Complications that include visual acuity decline, prolonged anterior chamber inflammation and ocular pain were evaluated during the 6 months follow-up. No significant difference was found between the two groups at baseline (p = 0.82) or final follow up (p = 1) regarding the IOP reduction; neovascularisation regression was observed only in the combined therapy group (66.6%). Micropulse transscleral cyclophotocoagulation with diode laser is an effective method of lowering intraocular pressure in cases of refractory glaucoma, with minimal ocular complications. Additionally, the association between mTSCPC and subconjunctival bevacizumab resulted in neovascularisation regression and IOP reduction. RezumatCiclofotocoagularea transsclerală micropulsată (mTSCPC) este o metodă de tratament pentru glaucomul refractar. Acest studiu evaluează eficacitatea și siguranța bevacizumabului administrat subconjunctival asociat cu mTSCPC față de mTSCPC în monoterapie. Au fost incluși în studiu șase pacienți cu glaucom neovascular, trei pacienți tratați cu mTSCPC în monoterapie și trei pacienți tratați cu o combinație de mTSCPC și bevacizumab subconjunctival. Au fost monitorizate presiunea intraoculară (IOP) și acuitatea vizuală, timp de 6 luni. Nu s-a constatat o diferență semnificativă între cele două grupuri la momentul includerii în studiu (p = 0,82), nici la finalul său (p = 1), în ceea ce privește reducerea PIO. Regresia neovascularizării a fost observată numai în grupul de terapie combinată (66,6%).

Our study aimed to determine pain levels and the state of welfare connected to laser-based procedures in the treatment of patients diagnosed with uncontrolled glaucoma. The study group included 100 eyes of 100 patients diagnosed with glucoma, 50 of them being treated with micropulse transscleral laser cyclophotocoagulation, and the other 50 eyes being treated with continuous transscleral laser cyclophotocoagulation. We used visual analog scale to gather information from each patient. After analysing the individual information the following results were obtained: the pain level for the micropulse transscleral laser cyclophotocoagulation was 60.23 mm, signifying moderate pain; and the pain score for the continuous transscleral laser cyclophotocoagulation was 76.34 mm, corresponding to moderate-intense pain. Pain level generated by minimally invasive laser procedures is discussed.

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