Use of Maximum Intensity Projections (MIPs) for target outlining in 4DCT radiotherapy planning
| Autor: | Sarah Muscat, Karen Moore, Rebecca Muirhead, Stuart G. McNee, Carrie Featherstone |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Internal target volume
Pulmonary and Respiratory Medicine Lung Neoplasms medicine.medical_treatment Planning target volume Computed tomography Stage ii Radiation Dosage Carcinoma Non-Small-Cell Lung medicine Humans Technology Radiologic Maximum intensity projections Retrospective Studies Maximum intensity medicine.diagnostic_test business.industry Radiotherapy Planning Computer-Assisted Radical radiotherapy 4DCT scans Radiation therapy Oncology Maximum intensity projection Non small cell Radiotherapy Intensity-Modulated Lung cancer Nuclear medicine business Tomography X-Ray Computed |
| Zdroj: | Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer. 3(12) |
| ISSN: | 1556-1380 |
| Popis: | Introduction Four-dimensional computed tomography (4DCT) is currently being introduced to radiotherapy centers worldwide, for use in radical radiotherapy planning for non-small cell lung cancer (NSCLC). A significant drawback is the time required to delineate 10 individual CT scans for each patient. Every department will hence ask the question if the single Maximum Intensity Projection (MIP) scan can be used as an alternative. Although the problems regarding the use of the MIP in node-positive disease have been discussed in the literature, a comprehensive study assessing its use has not been published. We compared an internal target volume (ITV) created using the MIP to an ITV created from the composite volume of 10 clinical target volumes (CTVs) delineated on the 10 phases of the 4DCT. Methods 4DCT data was collected from 14 patients with NSCLC. In each patient, the ITV was delineated on the MIP image (ITV_MIP) and a composite ITV created from the 10 CTVs delineated on each of the 10 scans in the dataset. The structures were compared by assessment of volumes of overlap and exclusion. Results There was a median of 19.0% (range, 5.5–35.4%) of the volume of ITV_10phase not enclosed by the ITV_MIP, demonstrating that the use of the MIP could result in under-treatment of disease. In contrast only a very small amount of the ITV_MIP was not enclosed by the ITV_10phase (median of 2.3%, range, 0.4–9.8%), indicating the ITV_10phase covers almost all of the tumor tissue as identified by MIP. Although there were only two Stage I patients, both demonstrated very similar ITV_10phase and ITV_MIP volumes. These findings suggest that Stage I NSCLC tumors could be outlined on the MIP alone. In Stage II and III tumors the ITV_10phase would be more reliable. Conclusions To prevent under-treatment of disease, the MIP image can only be used for delineation in Stage I tumors. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|