Film dose analysis system and its application in radiotherapy verification / 南方医科大学学报

<p><b>OBJECTIVE</b>To propose a new computer software-based medical image processing technique with high resolution digital scanner for radiotherapy verification.</p><p><b>METHODS</b>Under the platform of Windows 2000, the software, programmed with Visual C++.NET, was developed according to modular design. All data of the films and the treatment planning system could be processed as images or dose curves for a robust result.</p><p><b>RESULTS</b>Many functions such as data acquisition, automatic analysis and computation and image processing were integrated in the system. Both geometric and dosimetric errors could be calculated at the same time to verify the radiotherapy accuracy.</p><p><b>CONCLUSION</b>This system has good accuracy and stability for cost-effective radiotherapy verification.</p>

Parotid dysfunction after various methods of radiotherapy for nasopharyngeal carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the radiation induced parotid dysfunction in nasopharyngeal carcinoma (NPC) patients who had received different methods of radiotherapy.</p><p><b>METHODS</b>From January 1996 to January 2000, 380 NPC patients were divided into conventional fraction (CF-175 patients), late-course accelerated hyperfractionation (LCAF-63 patients) and intensity modulated radiation therapy (IMRT-142 patients) groups. Conventional radiotherapy was given with a total dose of 70 Gy. Patients in the LCAF group were treated with the same fractionation as CF group until the dose of 36 - 40 Gy, then followed by LCAF radiotherapy to a total dose of 75 Gy. IMRT in the form of full-course was given to a total dose of 72 Gy. Acute parotiditis was observed during the treatment. The parotid secretory function was examined 2 years after radiotherapy.</p><p><b>RESULTS</b>The dose of parotid in IMRT was much lower than those in the other 2 groups. Extreme damage rates of parotid secretory function in CF, LCAF and IMRT groups were 81.7%, 81.0% and 69.7% (P < 0.05); acute parotiditis rates were 23.4%, 20.4% and 41.3% respectively, with the differences among the 3 groups significant (P < 0.05).</p><p><b>CONCLUSION</b>The radiation parotid functional damage differs in the various methods of radiotherapy. IMRT, being able to improve the tumor target coverage and spare the adjacent critical structures, is indicated for NPC.</p>