Emergency irradiation with 3.4 Gy/2f in sellar/suprasellar germinoma patients with rapid visual acuity decline

Background: Rapid visual acuity (VA) decline was a common complaint in patients with sellar/suprasellar germinoma. In our hospital, 3.4 Gy/2f of emergency irradiation was applied to save patient VA and enable subsequent chemoradiotherapy. This study aimed to investigate the efficacy of emergency irradiation with 3.4 Gy/2f in patients with sellar/suprasellar germinoma who had rapid VA decline. Methods: From January 2014 to December 2017, 33 patients with sellar/suprasellar germinoma who complained of VA decline within 3 months received 3.4 Gy/2f of emergency irradiation in Beijing Tiantan Hospital. The best-corrected VA (BCVA) and mean deviation (MD) were measured. Correlations between visual function change and clinical factors, including age at diagnosis, duration of VA decline, extent of tumor regression, serum level of tumor markers, were analyzed. Results: Among 33 patients with sellar/suprasellar germinoma, the median diameter and volume of sellar/suprasellar lesions were 32 mm (range: 5–55 mm) and 12.9 cm3 (range 0.6–58.5 cm3), respectively. Data on pre- and post-emergency-irradiation BCVA were obtained in 32 patients. For the right eyes, BCVA was improved in 23 patients (71.9%), unchanged in 7 (21.9%), and worsened in 2 (6.2%);and for the left eyes, these numbers were 27 (84.4%), 4 (12.5%), and 1 (3.1%), respectively. In terms of the logarithm of the minimum angle of resolution (logarithm of the minimum angle of resolution = Log (1/BCVA) score, the improvement was significant in both eyes (P < 0.001). In terms of MD, six patients had paired data and the improvement was marginal in the right eyes (P = 0.068) and significant in the left eyes (P = 0.043). However, no clinical factor was found to have correlation with visual function improvement. Conclusion: In sellar/suprasellar germinoma patients with VA decline, 3.4 Gy/2f of emergency irradiation was effective in improving visual function.

Effect of water loss during curing on hydration reaction and hydrates conversion in calcium aluminate cement-bonded castables

Free water available in calcium aluminate cement(CAC)-bonded castables is crucial for the hydration of CAC and the conversion of hydration products in the curing and drying processes,as both the hydration and conversion reactions are dissolution–precipitation reactions.To elucidate the effect of different levels of free water loss upon the hydration of CAC,the conversion of hydration products and the mechanical strength of the CAC-bonded castables,the CAC-bonded castables were subjected to sealed and unsealed curing conditions at 50℃ and drying at 110℃.The results demonstrate that the fast removal of free water during unsealed curing would hinder the conversion from 2CaO·Al_(2)O_(3)·8H_(2)O to 3CaO·Al_(2)O_(3)·6H_(2)O and consequently prevent the deterioration of strength.As a comparison,although sealed-cured samples have less water loss and high degree of hydration of CAC,they still show lower strength than the unsealed samples after curing.The following drying process further accelerates the hydration of residual calcium aluminate clinkers for both the sealed and unsealed samples,but still does not favor the conversion from 2CaO·Al_(2)O_(3)·8H_(2)O to 3CaO·Al_(2)O_(3)·6H_(2)O in the unsealed-cured samples.