Transcranial sonography: integration into target volume definition for glioblastoma multiforme  Dirk Vordermark, M.D., Georg Becker, M.D., Michael Flentje, M.D., Susanne Richter, Ph.D., Irene Goerttler-Krauspe, M.D., Oliver Koelbl, M.D.  International Journal of Radiation Oncology • Biology • Physics  Volume 47, Issue 3, Pages 565-571 (June 2000) DOI: 10.1016/S0360-3016(00)00565-4

Fig. 1 Schematic illustration of gross target volume (GTV) and planning target volume (PTV, 3-mm margin), as used in the study. International Journal of Radiation Oncology • Biology • Physics 2000 47, 565-571DOI: (10.1016/S0360-3016(00)00565-4)

Fig. 2 Contribution of CT and TCS to the composite GTV of both methods in individual patients with GBM at the time of postoperative radiotherapy planning. Overlap of both methods and proportion of composite GTV recognized by only CT or TCS is shown. International Journal of Radiation Oncology • Biology • Physics 2000 47, 565-571DOI: (10.1016/S0360-3016(00)00565-4)

Fig. 3 Effect of integration of TCS into PTV definition after subtotal resection of GBM: Increase of PTV after generation of a 3-mm margin around the composite GTV defined by CT and TCS vs. 3-mm margin around GTV on CT. Note that the CT-PTV includes the “CT-only” GTV and the “overlap” GTV from Fig. 2. International Journal of Radiation Oncology • Biology • Physics 2000 47, 565-571DOI: (10.1016/S0360-3016(00)00565-4)

Fig. 4 Coverage of the contrast-enhancing area at time of progression, as determined by CT or MRI, by the 80% isodose of the stereotactic boost plans calculated for PTV defined by CT (PTVCT) or by combination of CT and TCS (PTVCT+TCS). All patients were conventionally irradiated after subtotal resection of GBM. International Journal of Radiation Oncology • Biology • Physics 2000 47, 565-571DOI: (10.1016/S0360-3016(00)00565-4)

Fig. 5 Volumes evaluated in a patient with left temporal GBM: comparison of TCS and corresponding portions of CT scans. (A) Postoperative TCS in a near-axial plane, anatomically corresponding to CT scan in B, as seen from the right temporal bone window. Resection cavity (1, solid line), choroid plexus (2), third ventricle (3), and frontal horn of the left lateral ventricle (4) are visible. The hyperechogenic area representing solid tumor (dotted line) extends further ventral than the contrast-enhancement zone in B. (B) Postoperative radiotherapy planning CT scan, showing only a thin zone of contrast enhancement at the anterior, medial, and posterior resection margin. (C) Follow-up CT at time of progression, showing contrast enhancement ventral and lateral of the enhancing area on planning CT. The patient subsequently developed a right arm paresis as a clinical sign of basal ganglia infiltration. (D) Integration of PTVCT (a, dotted line), PTVCT+TCS (b, hatched line; each with 3-mm margins), and contrast-enhancement at progression (c, solid line) in the initial planning CT scan shown in B. In this section, the area of progression is completely inside the PTVCT+TCS, but partially outside PTVCT. International Journal of Radiation Oncology • Biology • Physics 2000 47, 565-571DOI: (10.1016/S0360-3016(00)00565-4)