Verification Of Dose Distributions Research Articles

Prompt gamma imaging system in particle therapy: a mini-review

Accurate in-vivo verification of beam range and dose distribution is crucial for the safety and effectiveness of particle therapy. Prompt gamma (PG) imaging, as a method for real-time verification, has gained prominence in this area. Currently, several PG imaging systems are under development, including gamma electron vertex imaging (GEVI), the Compton camera, the slit camera, and the multi-array type collimator camera. However, challenges persist in dose prediction accuracy, largely due to patient positioning uncertainty and anatomical changes. Although each system demonstrates potential in verifying PG range, further improvements in detection efficiency, spatial resolution, background reduction, and integration into clinical workflows are essential.

Study of PRESAGE® dosimeter for end-to-end 3D radiotherapy verification using an anthropomorphic phantom with bespoke dosimeter insert.

Modern radiotherapy techniques have advanced and become more sophisticated. End-to-end 3D verification of the complex radiotherapy dose distribution in an anthropomorphic phantom can ensure the accuracy of the treatment delivery. The phantoms commonly used for dosimetry are homogeneous solid water phantom which lacks the capability to measure the 3D dose distribution for heterogeneous tissues necessary for advanced radiotherapy techniques. Therefore, we developed an end-to-end 3D radiotherapy dose verification system based on MAX-HD anthropomorphic phantom (Integrated Medical Technologies Inc., Troy, New York) with bespoke intracranial insert for PRESAGE® dosimeter. In this study, several advanced radiotherapy treatment techniques of various levels of complexity; 3D-CRT, IMRT and VMAT treatment, were planned for a 20mm diameter of a spherical target in the brain region and delivered to the phantom. The dosimeters were read out using an in-house developed optical computed tomography (OCT) imaging system known as 3DmicroHD-OCT. It was found that the measured dose distribution of the PRESAGE® when compared with the measured dose distribution of EBT film and Monaco TPS has a maximum difference of less than 3% for 3D-CRT, IMRT and VMAT treatment plans. The gamma analysis results of PRESAGE® in comparison to EBT film and Monaco TPS show pass rates of more than 95% for the criteria of 3% dose difference and 3mm distance-to-agreement. This study proves the capability of PRESAGE® and bespoke MAX-HD phantom in conjunction with the 3DmicroHD-OCT system to measure 3D dose distribution for end-to-end dosimetry verification.

Development of a novel delivery quality assurance system based on simultaneous verification of dose distribution and binary multi-leaf collimator opening in helical tomotherapy

BackgroundIntensity-modulated radiation therapy (IMRT) requires delivery quality assurance (DQA) to ensure treatment accuracy and safety. Irradiation techniques such as helical tomotherapy (HT) have become increasingly complex, rendering conventional verification methods insufficient. This study aims to develop a novel DQA system to simultaneously verify dose distribution and multi-leaf collimator (MLC) opening during HT.MethodsWe developed a prototype detector consisting of a cylindrical plastic scintillator (PS) and a cooled charge-coupled device (CCD) camera. Scintillation light was recorded using a CCD camera. A TomoHDA (Accuray Inc.) was used as the irradiation device. The characteristics of the developed system were evaluated based on the light intensity. The IMRT plan was irradiated onto the PS to record a moving image of the scintillation light. MLC opening and light distribution were obtained from the recorded images. To detect MLC opening, we placed a region of interest (ROI) on the image, corresponding to the leaf position, and analyzed the temporal change in the light intensity within each ROI. Corrections were made for light changes due to differences in the PS shape and irradiation position. The corrected light intensity was converted into the leaf opening time (LOT), and an MLC sinogram was constructed. The reconstructed MLC sinogram was compared with that calculated using the treatment planning system (TPS). Light distribution was obtained by integrating all frames obtained during IMRT irradiation. The light distribution was compared with the dose distribution calculated using the TPS.ResultsThe LOT and the light intensity followed a linear relationship. Owing to MLC movements, the sensitivity and specificity of the reconstructed sinogram exceeded 97%, with an LOT error of − 3.9 ± 7.8%. The light distribution pattern closely resembled that of the dose distribution. The average dose difference and the pass rate of gamma analysis with 3%/3 mm were 1.4 ± 0.2% and 99%, respectively.ConclusionWe developed a DQA system for simultaneous and accurate verification of both dose distribution and MLC opening during HT.

Iterative Image Reconstruction Methodology in Optical CT Radiochromic Gel Dosimetry

Modern advancements in radiation therapy require paralleled advancements in the dosimetric tools used to verify dose distributions. Optical computed tomography (CT) imaged radiochromic gel dosimeters provide comprehensive, tissue equivalent, 3D dosimetric information with high spatial resolution and low imaging times. Traditional CT image reconstruction methods (filtered backprojection) do not account for light refraction within the optical CT system reducing the image quality. Iterative reconstruction methods make use of a system matrix that describes this light refraction thus, improving the reconstructed image quality. However, use of iterative reconstruction methods is not widespread, largely due to the impractical storage size of the required system matrix. Furthermore, current iterative reconstruction methods do not address the issue of image degradation due to a single detector element collecting light from multiple raypaths. For optical CT radiochromic gel dosimetry to be used effectively as a radiation therapy treatment plan verification tool, the system must be both practical and accurate. Thus, this work has two main objectives: (i) reduce the size of system matrices by means of polar coordinate discretization in lieu of the traditional Cartesian coordinate discretization, and (ii) reduce image degradation due to multiple raypaths by a novel approach to populating the system matrix that accounts for multiple raypaths.

ART2Dose: A comprehensive dose verification platform for online adaptive radiotherapy.

Online adaptive radiotherapy (ART) involves the development of adaptable treatment plans that consider patient anatomical data obtained right prior to treatment administration, facilitated by cone-beam computed tomography guided adaptive radiotherapy (CTgART) and magnetic resonance image-guided adaptive radiotherapy (MRgART). To ensure accuracy of these adaptive plans, it is crucial to conduct calculation-based checks and independent verification of volumetric dose distribution, as measurement-based checks are not practical within online workflows. However, the absence of comprehensive, efficient, and highly integrated commercial software for secondary dose verification can impede the time-sensitive nature of online ART procedures. The main aim of this study is to introduce an efficient online quality assurance (QA) platform for online ART, and subsequently evaluate it on Ethos and Unity treatment delivery systems in our clinic. To enhance efficiency and ensure compliance with safety standards in online ART, ART2Dose, a secondary dose verification software, has been developed and integrated into our online QA workflow. This implementation spans all online ART treatments at our institution. The ART2Dose infrastructure comprises four key components: an SQLite database, a dose calculation server, a report generator, and a web portal. Through this infrastructure, file transfer, dose calculation, report generation, and report approval/archival are seamlessly managed, minimizing the need for user input when exporting RT DICOM files and approving the generated QA report. ART2Dose was compared with Mobius3D in pre-clinical evaluations on secondary dose verification for 40 adaptive plans. Additionally, a retrospective investigation was conducted utilizing 1302 CTgART fractions from ten treatment sites and 1278 MRgART fractions from seven treatment sites to evaluate the practical accuracy and efficiency of ART2Dose in routine clinical use. With dedicated infrastructure and an integrated workflow, ART2Dose achieved gamma passing rates that were comparable to or higher than those of Mobius3D. Additionally, it significantly reduced the time required to complete pre-treatment checks by 3-4 min for each plan. In the retrospective analysis of clinical CTgART and MRgART fractions, ART2Dose demonstrated average gamma passing rates of 99.61±0.83% and 97.75±2.54%, respectively, using the 3%/2mm criteria for region greater than 10% of prescription dose. The average calculation times for CTgART and MRgART were approximately 1 and 2 min, respectively. Overall, the streamlined implementation of ART2Dose notably enhances the online ART workflow, offering reliable and efficient online QA while reducing time pressure in the clinic and minimizing labor-intensive work.

PD-0501 Superficial HDR brachytherapy - dosimetric verification of dose distribution with lead shielding

PD-0501 Superficial HDR brachytherapy - dosimetric verification of dose distribution with lead shielding

Comparison of two pre-treatment verification methods for arc – IMRT plans

In radiotherapy, the application of the IMRT arc technique, a special technique of external beam irradiation, while providing greater ballistic accuracy and personalization of treatment, as well as better speed of execution, requires special attention to the development of the treatment plan and its verification.Therefore, tools and methods of physical-health analysis that allow verification of the accuracy of the delivery of the radiant beam in the stages prior to treatment are essential. At the unit of Medical Physics at Dimiccoli Hospital Barletta, a prospective experimental study was conducted based on the comparison of two different methods of pre-treatment verification in patients treated for prostate cancer with the aim of increasing the performance of the treatment workflow.A comparative evaluation of gamma analysis results on images acquired with a 2D flat panel detector EPID (Electronic Portal Imaging Device) on the one hand and a 2D ionizing chambers detector on the other hand was conducted. The study sample included 38 patients undergoing radiotherapy with IMRT between December 2021 and October 2022, and each subject was studied and verified with both methods.The results of gamma analysis conducted with the two methods of pre-treatment verification of patients with prostate cancer are superimposable. In addition, with EPID we have a significant saving of machine time and thus allows an increase in the number of patients undergoing daily radiotherapy.In light of internationally accepted dosimetric and radiation protection accuracy standards according to Decree 101/2020, pre-treatment verification of dose distributions, using a 2D flat panel detection system (EPID), was found to be in line with waiting list reduction goals.

Experiment of proof-of-principle on prompt gamma-positron emission tomography (PG-PET) system for in-vivo dose distribution verification in proton therapy

In our previous study, we proposed an integrated PG-PET-based imaging method to increase the prediction accuracy for patient dose distributions. The purpose of the present study is to experimentally validate the feasibility of the PG-PET system. Based on the detector geometry optimized in the previous study, we constructed a dual-head PG-PET system consisting of a 16 × 16 GAGG scintillator and KETEK SiPM arrays, BaSO4 reflectors, and an 8 × 8 parallel-hole tungsten collimator. The performance of this system as equipped with a proof of principle, we measured the PG and positron emission (PE) distributions from a 3 × 6 × 10 cm3 PMMA phantom for a 45 MeV proton beam. The measured depth was about 17 mm and the expected depth was 16 mm in the computation simulation under the same conditions as the measurements. In the comparison result, we can find a 1 mm difference between computation simulation and measurement. In this study, our results show the feasibility of the PG-PET system for in-vivo range verification. However, further study should be followed with the consideration of the typical measurement conditions in the clinic application.

The feasibility of the pretreatment verification of 2D dose distributions in radiation therapy with small fields using the electronic portal imaging device.

The present study aims to evaluate the performance of an Electronic portal imaging device (EPID) for measuring dosimetric parameters and for verification of dose in small photon fields. In this study, the beam profiles were obtained using the amorphous silicon (a-Si) EPID for field sizes ranging from 1 × 1 to 10 × 10 cm 2 at energies 6 and 18 mega-voltage (MV). For comparison, the dosimetric parameters, including penumbra widths and field sizes, were measured with the pinpoint, diode, and Semiflex dosimeters. Finally, Rando Phantom was used to compare the two-dimensional (2D) Dose distribution between EPID and Treatment Planning System (TPS). In both 5 cm and 10 cm depths, there were large differences between the measured doses obtained from TPS, Pinpoint detector, and Farmer detector in 1 × 1 field size. The differences become negligible as the field sizes increase and from 3 × 3 field size to 10 × 10 field size, the maximum observed differences are 2 cGy and 2.4 cGy for 5 cm and 10 cm depths, respectively. The results indicate that the penumbra widths are smaller in the Gantry-Target (GT) direction compared to the Right-Left (RL) direction. The maximum difference (47.6%) was observed for EPID in the 10 × 10 field size, and the minimum difference (16.6%) was observed for TPS in the 1 × 1 field size. Finally, 2D dose distributions obtained by EPID and TPS exhibit excellent agreement. EPID is an excellent tool for the measurement of dosimetry parameters such as dose profiles, penumbra widths, field sizes, and pretreatment verification of 2D dose distributions, especially in small fields.

Verification of dose distribution by different material properties in intraoral mold irradiation

Verification of dose distribution by different material properties in intraoral mold irradiation

Verification of Dose Distribution in Cervical Cancer Brachytherapy Using Metal and Plastic Applicators

To validate the point-A dose and dose distribution of metal and resin applicators in comparison with those of TG-43U1. The metal and resin applicators consisting of tandem and ovoid were modeled by the egs_brachy. The doses to point A and dose distributions considering each applicator were calculated and compared to those of TG-43U1. The dose to point A considering the metal applicator was 3.2% lower than that of TG-43U1, but there was no difference in the dose to point A considering the resin applicator. The dose distribution considering the metal applicator was lower than that of TG-43U1 at all calculation points, but there was no difference in the dose distribution considering the resin applicator at almost all calculation points. In this study, the dose distribution considering the metal applicator was lower than that of TG-43U1 at all calculation points, but there was no difference in the dose distribution considering the resin applicator at almost all calculation points. Therefore, TG-43U1 can accurately calculate the dose distribution when changing from the metal applicator to the resin applicator.

Dose verification of virtual bolus application for helical tomotherapy.

The objective of the study is to verify the dose delivered on helical tomotherapy based on treatment plan with varying virtual bolus (VB) thickness. The target was localized on the ArcCHECK image by 3 mm margin from the phantom surface. The dimension of target, which includes the ArcCHECK's detectors, with the 4.0 cm width and length 12.0 cm along the phantom The 5 treatment plans were generated, 1 plan without VB application (NoVB) and the 4 plans with varying of VB thickness on the phantom surface by 0.5 cm (VB0.5), 1.0 cm (VB1.0), 1.5 cm (VB1.5), and 2.0 cm (VB2.0), in treatment planning but absent during irradiation. For measurement analysis, the ionization chamber and the ArcCHECK detectors were used for point dose and dose distribution by investigating the percentage of dose difference and the gamma passing rate. The VB thickness 0.5, 1.0 and 1.5 cm showed acceptable value with less than 2% for dose difference by 0.37% (VB0.5), -0.11% (VB1.0) and -0.37% (VB1.5) at the center of ArcCHECK. The accuracy of dose distribution showed an acceptable gamma passing rate of 99.8% (VB0.5), 100% (VB1.0), and 90.2% (VB1.5) for gamma criteria by 3%/3mm for absolute dose analysis. However, the gamma passing rate of VB2.0 down to 71.2% of absolute mode for gamma criteria by 3%/3mm. The treatment plans with VB thickness less than 15 mm deliver doses that are comparable to treatment plans without virtual bolus based on gamma analysis. However, the deviation showed a trend increasing when VB thickness increased. The VB2.0 was not acceptable for point dose and dose distribution verification by more than 2% dose difference and less than 90% of gamma passing rate.

Predicting the complexity of head-and-neck volumetric-modulated arc therapy planning using a radiation therapy planning quality assurance software.

The more complex the treatment plan, the higher the possibility of errors in dose verification. Recently, a treatment planning quality assurance (QA) software (PlanIQ) with a function to objectively evaluate the quality of volumetric-modulated arc therapy (VMAT) treatment plans by scoring and calculating the ideal dose-volume histogram has been marketed. This study aimed to assess the association between the scores of ideal treatment plans identified using PlanIQ and the results of dose verification and to investigate whether the results of dose verification can be predicted based on the complexity of treatment plans. Dose verification was performed using an ionization chamber dosimeter, a radiochromic film, and a three-dimensional dose verification system, Delta4 PT. Correlations between the ideal treatment plan scores obtained by PlanIQ and the results of the absolute dose verification and dose distribution verification were obtained, and it was examined whether dose verifications could be predicted from the complexity of the treatment plans. Even when the score from the ideal treatment plan was high, the results of absolute dose verification and dose distribution verification were sometimes poor. However, even when the score from the ideal treatment plan was low, the absolute volume verification and dose distribution verification sometimes yielded good results. Treatment plan complexity can be determined in advance from the ideal treatment plan score calculated by PlanIQ. However, it is difficult to predict the results of dose verification using an ideal treatment plan.

Influence of different air CT numbers for IVDT on the dose distribution in TomoTherapy MVCT.

This study aims to evaluate the effect of different air computed tomography (CT) numbers of the image value density table (IVDT) on the retrospective dose calculation of head-and-neck (HN) radiotherapy using TomoTherapy megavoltage CT (MVCT) images. The CT numbers of the inside and outside air and each tissue-equivalent plug of the "Cheese" phantom were obtained from TomoTherapy MVCT. Two IVDTs with different air CT numbers were created and applied to MVCT images of the HN anthropomorphic phantom and recalculated by Planned Adaptive to verify dose distribution. We defined the recalculation dose with MVCT images using both inside and outside air of the IVDT as and , respectively. Treatment planning doses calculated on kVCT images were compared with those calculated on MVCT images using two different IVDT tables, namely, and . The difference between average MVCT numbers ±1 standard deviation on inside and outside air of the calibration phantom was 65±36HU. This difference in MVCT number of air exceeded the recommendation lung tolerance for dose calculation error of 2%. The dose differences between the planning target volume (PTV): D98% , D50% , D2% and the organ at risk (OAR): Dmax , Dmean recalculated by and using MVCT images were a maximum of 0.7% and 1.2%, respectively. Recalculated doses to the PTV and OAR with MVCT showed that was 0.5%-0.7% closer to the kVCT treatment planning dose than . This study showed that was more accurate than in recalculating the dose HN cases of MVCT using TomoTherapy.

Personalized Superficial HDR Brachytherapy-Dosimetric Verification of Dose Distribution with Lead Shielding of Critical Organs in the Head and Neck Region.

Background: Surface brachytherapy, usually characterized by a high dose gradient, allows the dose to be precisely deposited in the irradiated area while protecting critical organs. When the lesion is located in the nasal or ocular region, the organ of vision must be protected. The aim of this study was to verify the dose distributions near critical organs in the head and neck region during a brachytherapy procedure using lead shielding of the eye. Methods: Anthropomorphic phantom using 3D-printing technology was prepared. The doses deposited at a point in the lens of the eye and on the surface of the eyelid, directly under the lead shield were calculated and measured using EBT3 radiochromic films. Comparison of doses planned in the treatment planning system using the TG-43 formalism, TG-186 formalism, and measured were also performed. Results: Comparing the planned and calculated doses with TG186 formalism it can be assumed that the use of lead shields is a method for protecting the organ of vision from the adverse effects of ionizing radiation. Conclusions: The decision to use a lead shield during facial surface brachytherapy procedures should be made on a patient-by-patient basis and based on model-based calculation methods recommended by TG186.

Three cases of retroperitoneal sarcoma in which bioabsorbable spacers (bioabsorbable polyglycolic acid spacers) were inserted prior to carbon ion radiotherapy.

From August 2019 to August 2020, we inserted polyglycolic acid (PGA) spacers and administered carbon ion radiotherapy (CIRT) to three cases of retroperitoneal sarcoma at our hospital. We aimed to investigate its utility and safety for retroperitoneal sarcoma. We analyzed changes in PGA spacer volume and corresponding computed tomography (CT) values in addition to the dose distribution using in-room CT images that were obtained during treatment. We assessed adverse events and investigated the suitability, safety and effectivity of PGA spacer insertion. During treatment, changes in PGA spacer volumes and CT values were confirmed. Volumes increased in patients with a folded PGA spacer, and it increased 1.6-fold by the end of irradiation compared with planning CT. The CT values decreased by 20–50 Hounsfield units at the end of irradiation compared to the planning CT. Dose distribution evaluation showed that the dose to the gastrointestinal tract adjacent to the tumor was maintained below the tolerable dose, and a sufficient dose was delivered to the target by PGA spacer insertion. One case of subileus caused during abdominal surgery for PGA spacer insertion occurred. No other adverse events, such as digestive disorders, were observed. CIRT with PGA spacer insertion for retroperitoneal sarcomas is safe and effective. For cases in which there is no option but to perform irradiation using a PGA spacer, precautionary measures such as verification of dose distributions using CT images are necessary.

Feasibility of a Reusable Radiochromic Dosimeter

The current practice for patient-specific quality assurance (QA) uses ion chambers or diode arrays primarily because of their ease of use and reliability. A standard routine compares the dose distribution measured in a phantom with the dose distribution calculated by the treatment planning system for the same experimental conditions. For the particular problems encountered in the treatment planning of complex radiotherapy techniques, such as small fields/segments and dynamic delivery systems, additional tests are required to verify the accuracy of dose calculations. The dose distribution verification should be throughout the total 3D dose distribution for a high dose gradient in a small, irradiated volume, instead of the standard practice of one to several planes with 2D radiochromic (GAFChromic) film. To address this issue, we have developed a 3D radiochromic dosimeter that improves the rigor of current QA techniques by providing high-resolution, complete 3D verification for a wide range of clinical applications. The dosimeter is composed of polyurethane, a radical initiator, and a leuco dye, which is radiolytically oxidized to a dye absorbing at 633 nm. Since this chemical dosimeter is single-use, it represents a significant expense. The purpose of this research is to develop a cost-effective reusable dosimeter formulation. Based on prior reusability studies, three promising dosimeter formulations were studied using small volume optical cuvettes and irradiated to known clinically relevant doses of 0.5–10 Gy. After irradiation, the change in optical density was measured in a spectrophotometer. All three formulations retained linearity of optical density response to radiation upon re-irradiations. However, only one formulation retained dose sensitivity upon at least five re-irradiations, making it ideal for further evaluation as a 3D dosimeter.

Improvement of light stability of DHR123 radio fluorogenic nano clay gel dosimeter by incorporating a new dispersant

A tissue-equivalent three-dimensional dosimeter is being developed to verify dose distributions for radiotherapy. Recently, we have reported a nanocomposite fluorescent gel (NC-RFG) dosimeter that enables readout by the fluorometry, which is more sensitive than absorption method in principle. However, irradiating by an excitation light for a dose information readout also produces fluorescent dyes and is not negligible in the low-dose irradiation range under 1 Gy. In this study, we investigate new additives to improve the NC-RFG’s light stability. We successfully suppressed the light-sensitive property of the NC-RFG to at least 10% of normal conditions by adding either N-vinylpyrrolidone or pyridine as a new dispersant that is presumed to break up aggregation of rhodamine 123 (RD123) and dihydrorhodamine 123 (DHR123) to stop photoexcited RD123 from oxidizing the adjacent DHR123. We also provide a detailed study of sensitivity characteristics such as dose rate dependence for fluorescent gel dosimeters.

Total body irradiation using helical tomotherapy: Set-up experience and in-vivo dosimetric evaluation

PurposeHelical Tomotherapy (HT) appears as a valuable technique for total body irradiation (TBI) to create highly homogeneous and conformal dose distributions with more precise repositioning than conventional TBI techniques. The aim of this work is to describe the technique implementation, including treatment preparation, planning and dosimetric monitoring of TBI delivered in our institution from October 2016 to March 2019. Material and methodPrior to patient care, irradiation protocol was set up using physical phantoms. Gafchromic films were used to assess dose distribution homogeneity and evaluate imprecise patient positioning impact. Sixteen patients’ irradiations with a prescribed dose of 12Gy were delivered in 6 fractions of 2Gy over 3 days. Pre-treatment quality assurance (QA) was performed for the verification of dose distributions at selected positions. In addition, in-vivo dosimetry was carried out using optically stimulated luminescence dosimeters (OSLD). ResultsPlanning evaluation, as well as results of pre-treatment verifications, are presented. In-vivo dosimetry showed the strong consistency of OSLD measured doses. OSLD mean relative dose differences between measurement and calculation were respectively +0,96% and −2% for armpit and hands locations, suggesting better reliability for armpit OSLD positioning. Repercussion of both longitudinal and transversal positioning inaccuracies on phantoms is depicted up to 2cm shifts. ConclusionThe full methodology to set up TBI protocol, as well as dosimetric evaluation and pre-treatment QA, were presented. Our investigations reveal strong correspondence between planned and delivered doses shedding light on the dose reliability of OSLD for HT based TBI in-vivo dosimetry.

A Novel Adjustable Anthropomorphic Head Phantom for Verifying the Dose of Radiation Therapy.

This study aims to make a phantom to verify dose distribution and compare two techniques of radiation therapy, including 3D conventional radiotherapy (3D-CRT) and modulated photon radiotherapy (IMRT). For treatment of brain cancer, physicians have to prescribe radiation therapy to involved patients so that organs at risk receive unwanted dose causing them to be damaged. To know precise dose delivered into them and evaluate treatment-planning system (TPs), it is necessary to do dosimetry in the phantom owing to difficulties of dosimetry in human. It is important to make a phantom with characteristics similar to humans and ability to compute dose and dose distribution in desired organs and tissue. Thus, there is possibility to compute dose in different parts, including doses delivered in ears, eyes, stem brain and optic nerve. Furthermore, this phantom has to provide this opportunity to investigate whether some techniques of radiation therapy such as 3D-CRT or IMRT depend on the size or location of tumors. To this end, a low workload, easy-to-set-up, lightweight, and transportable phantom was designed, and made from Polylactic acid (PLA) in dimensions 23×24×32 cm3. The phantom consists of brain, tumors in different dimeters, including 2, 4, 6 cm and also parts for eyes and ears to locate TLDs. Head, brain and tumors are able to open so that they can be filled with polymer gel dosimetry making possible record dose distribution in three-dimensions (3D) and sharp dose gradients.