Comparison of daily megavoltage electronic portal imaging or kilovoltage imaging with marker seeds to ultrasound imaging or skin marks for prostate localization and treatment positioning in patients with prostate cancer

Clinical Application of Ultrasound Imaging in Radiation Therapy

“…Therefore, 1 cm is a typical expansion around the prostate CTV to create the PTV without imaging (Hanks et al, 2000;Boersma et al, 1998). With daily ultrasound imaging, we have found that the 95 % confidence interval is reduced to 0.7 cm which agrees with Serago et al (Serago et al, 2006). Boda-Heggemann et al and Langen et al also demonstrated that ultrasound imaging improves prostate localization (BodaHeggemann et al, 2008;Langen et al, 2003).…”

“…Such a large displacement is rare (typically less than 7 % of the time). A few millimetres are more typical on a daily basis, and it is less than 1 cm (0.8 -0.9 mm) with a 95 % confidence interval (Scarborough et al, 2006;Serago et al, 2006). Therefore, 1 cm is a typical expansion around the prostate CTV to create the PTV without imaging (Hanks et al, 2000;Boersma et al, 1998).…”

“…Boda-Heggemann et al and Langen et al also demonstrated that ultrasound imaging improves prostate localization (BodaHeggemann et al, 2008;Langen et al, 2003). Serago et al and Langen et al identified a significant improvement in localization in the anterior-posterior direction which is the direction of largest prostate displacement because of rectal filling (Serago et al, 2006;Langen et al, 2003). Further, the rectum and bladder are adjacent to the prostate, but are critical structures that should be spared as much dose as is possible without compromising the delivery of the prescribed dose to the prostate.…”

Stereotactic Body Radiotherapy for Pancreatic Adenocarcinoma: Set-Up Error Correction Using Internal Markers and It’s Association with the Patient’s Body Mass Index

“…Image-guided respiratory-gated radiation therapy has been a major advancement in minimizing inter-and intra-fractional target variations. To minimize and correct for setup uncertainties and inter-fractional motion of extracranial tumors, various immobilization and localization techniques have been clinically implemented, including transabdominal ultrasonography (Lattanzi et al 1999;Chandra et al 2003;Langen et al 2003), megavoltage imaging (Schiffner et al 2007;Serago et al 2006), kilovoltage imaging (Jaffray et al 1999;Kupelian et al 2008), use of an in-room computed tomography (CT)-linear accelerator system (Court et al 2003;Wong et al 2005), cone-beam CT (Jaffray et al 1999;Kupelian et al 2008), and placement of internal fiducials (Kupelian et al 2008;Chen et al 2007;Chung et al 2004). Pancreatic tumor targets usually exhibit inter-fractional motion relative to the bony anatomy because of daily variation in stomach and duodenal filling and respiratory patterns.…”

Reprodutibilidade de posicionamento em radioterapia

“…Digital images can be digitally superimposed over DRR images, making the localization process much easier by means of a process known as image-guided radiotherapy (IGRT) (2) . However, due to the intrinsic characteristics of the radiation energy used for such purpose, portal images made from the same radiation beam used for treatment present low contrast resolution, which impairs the clear visualization of structures at some anatomic sites, besides not allowing the visualization of the patient's physiological condition or the accurate target volume positioning when based on soft tissues (3,4) .…”