RESUMEN
PURPOSE: To evaluate the quality of fully automated stereotactic body radiation therapy (SBRT) planning based on volumetric modulated arc therapy, which can reduce the reliance on historical plans and the experience of dosimetrists. METHODS: Fully automated re-planning was performed on twenty liver cancer patients, automated plans based on automated SBRT planning (ASP) program and manual plans were conducted and compared. One patient was randomly selected and evaluate the repeatability of ASP, ten automated and ten manual SBRT plans were generated based on the same initial optimization objectives. Then, ten SBRT plans were generated for another selected randomly patient with different initial optimization objectives to assess the reproducibility. All plans were clinically evaluated in a double-blinded manner by five experienced radiation oncologists. RESULTS: Fully automated plans provided similar planning target volume dose coverage and statistically better organ at risk sparing compared to the manual plans. Notably, automated plans achieved significant dose reduction in spinal cord, stomach, kidney, duodenum, and colon, with a median dose of D2% reduction ranging from 0.64 to 2.85 Gy. R50% and Dmean of ten rings for automated plans were significantly lower than those of manual plans. The average planning time for automated and manual plans was 59.8 ± 7.9 min vs. 127.1 ± 16.8 min (- 67.3 min). CONCLUSION: Automated planning for SBRT, without relying on historical data, can generate comparable or even better plan quality for liver cancer compared with manual planning, along with better reproducibility, and less clinically planning time.
Asunto(s)
Neoplasias Hepáticas , Radiocirugia , Radioterapia de Intensidad Modulada , Humanos , Reproducibilidad de los Resultados , Planificación de la Radioterapia Asistida por Computador , Dosificación Radioterapéutica , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Órganos en RiesgoRESUMEN
OBJECTIVE: To establish normal ranges of F-wave measures in China as compared to published data in Brazil and Japan. METHOD: We studied F waves in 127 healthy Chinese subjects, aged 21-78 years old, stimulating the median, ulnar, tibial and peroneal nerves distally and proximaly. RESULT: The F-wave latencies had a linear correlation to the subject height in all nerves tested, showing a steeper (P < 0.05) regression line in Brazil compared to China and Japan for the tibial nerve. The Chinese population also had a higher distally elicited F-wave persistence and faster F wave conduction velocities than previously reported for both ulnar and tibial nerves. These values showed significant difference (P < 0.05) compared to Brazil but not to Japan. CONCLUSION: F-wave latencies show a linear correlation to subject height, although the slope of regression lines varies among countries, reflecting the difference in F-wave persistence and F-wave conduction velocity. SIGNIFICANCE: Our study provides a rational for the use of a latency-height nomogram in clinical studies and underscores the importance of developing country specific normative data.