The Delta4DVH Anatomy 3D quality assurance (QA) system (ScandiDos), which converts the measured detector dose into the dose distribution in the patient geometry was evaluated. It allows a direct comparison of the calculated 3D dose with the measured back‐projected dose. In total, 16 static and 16 volumetric‐modulated arc therapy (VMAT) fields were planned using four different energies. Isocenter dose was measured with a pinpoint chamber in homogeneous phantoms to investigate the dose prediction by the Delta4DVH Anatomy algorithm for static fields. Dose distributions of VMAT fields were measured using GAFCHROMIC film. Gravitational gantry errors up to 10° were introduced into all VMAT plans to study the potential of detecting errors. Additionally, 20 clinical treatment plans were verified. For static fields, the Delta4DVH Anatomy predicted the isocenter dose accurately, with a deviation to the measured phantom dose of 1.1normal%±0.6normal%. For VMAT fields the predicted Delta4DVH Anatomy dose in the isocenter plane corresponded to the measured dose in the phantom, with an average gamma agreement index (GAI) false(3 mm/3normal%false) of 96.9±0.4normal%. The Delta4DVH Anatomy detected the induced systematic gantry error of 10° with a relative GAI false(3 mm/3normal%false) change of 5.8normal%±1.6normal%. The conventional Delta4PT QA system detected a GAI change of 4.2normal%±2.0normal%. The conventional Delta4PT GAI false(3 mm/3normal%false) was 99.8normal%±0.4normal% for the clinical treatment plans. The mean body and PTV‐GAI false(3 mm/5normal%false) for the Delta4DVH Anatomy were 96.4normal%±2.0normal% and 97.7normal%±1.8normal%; however, this dropped to 90.8normal%±3.4normal% and 87.1normal%±4.1normal% for passing criteria of 3 mm/3normal%. The anatomy‐based patient specific quality assurance system predicts the dose distribution correctly for a homogeneous case. The limiting factor for the error detection is the large variability in the error‐free plans. The dose calculation algorithm is inferior to that used in the TPS (Eclipse).PACS numbers: 87.56.Fc, 87.56.‐v

In vivo imaging of tissue/vasculature oxygen saturation levels is of prime interest in many clinical applications. To this end, the feasibility of combining two distinct and complementary imaging modalities is investigated: optoacoustics (OA) and near-infrared optical tomography (NIROT), both operating noninvasively in reflection mode. Experiments were conducted on two optically heterogeneous phantoms mimicking tissue before and after the occurrence of a perturbation. OA imaging was used to resolve submillimetric vessel-like optical absorbers at depths up to 25 mm, but with a spectral distortion in the OA signals. NIROT measurements were utilized to image perturbations in the background and to estimate the light fluence inside the phantoms at the wavelength pair (760 nm, 830 nm). This enabled the spectral correction of the vessel-like absorbers' OA signals: the error in the ratio of the absorption coefficient at 830 nm to that at 760 nm was reduced from 60%-150% to 10%-20%. The results suggest that oxygen saturation (SO ) levels in arteries can be determined with<10% error and furthermore, that relative changes in vessels' SO can be monitored with even better accuracy. The outcome relies on a proper identification of the OA signals emanating from the studied vessels.

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