Biochemical differentiation between cancerous and normal human colorectal tissues by micro-Raman spectroscopy.

Human colorectal tissues obtained by ten cancer patients have been examined by multiple micro-Raman spectroscopic measurements in the 500-3200 cm-1 range under 785 nm excitation. Distinct spectral profiles are recorded from different spots on the samples: a predominant 'typical' profile of colorectal tissue, as well as those from tissue topologies with high lipid, blood or collagen content. Principal component analysis identified several Raman bands of amino acids, proteins and lipids which allow the efficient discrimination of normal from cancer tissues, the first presenting plurality of Raman spectral profiles while the last showing off quite uniform spectroscopic characteristics. Tree-based machine learning experiment was further applied on all data as well as on filtered data keeping only those spectra which characterize the largely inseparable data clusters of 'typical' and 'collagen-rich' spectra. This purposive sampling evidences statistically the most significant spectroscopic features regarding the correct identification of cancer tissues and allows matching spectroscopic results with the biochemical changes induced in the malignant tissues.

RADIATION DOSES TO THE EYE LENS AND FOREHEAD OF INTERVENTIONAL RADIOLOGISTS: HOW HIGH AND ON WHAT GROUNDS?

The aim of the study was to measure and evaluate the radiation dose to the eye lens and forehead of interventional radiologists (IRs). The study included 96 procedures (lower-limb percutaneous transluminal angioplasties, embolisations/chemoembolisations and vertebroplasties) performed by 6 IRs. A set of seven thermoluminescence dosemeters was allocated to each physician. The highest dose per procedure was found for the left eye lens of the primary operator in vertebroplasties (1576 µSv). Left and right eye doses were linearly correlated to left and right forehead doses, respectively. A workload-based estimation of the annual dose to participating IRs revealed that the occupational dose limit for the eye lens can be easily exceeded. The left eye dose of ΙRs must be routinely monitored on a personalised basis. Τhe left eye dose measurement provides a reliable assessment of the ipsilateral forehead dose, along with valid estimations for the right eye and right forehead doses.

Computed-tomography-guided transforaminal intrathecal nusinersen injection in adults with spinal muscular atrophy type 2 and severe spinal deformity. Feasibility, safety and radiation exposure considerations.

BACKGROUND AND PURPOSE: The purpose was to investigate our centre's experience on computed-tomography-guided (CT-guided), transforaminal, intrathecal administration of nusinersen in adult subjects with spinal muscular atrophy (SMA) type 2 and severe spinal deformity. METHOD: This is a retrospective, single-centre study investigating the feasibility and safety of CT-guided, transforaminal, lumbar puncture for the intrathecal administration of nusinersen (Spinranza®; Biogen; Cambridge, MA, USA) in a cohort of adult subjects with SMA type 2, severe neuromuscular scoliosis and previous spinal surgery. Between January 2019 and October 2019, five male, adult, SMA type 2 subjects were eligible to be treated in our centre with nusinersen. The mean age of the patients was 31 ± 9 years (range 19-43 years). The study's outcome measures were technical success, adverse events and radiation exposure. RESULTS: In total, four patients completed the four loading doses, whilst the fifth patient received only one loading dose; two patients also received their first maintenance doses. Overall, 20 consecutive transforaminal, intrathecal treatments were analysed. Technical success was 100% (20/20 intrathecal infusions). No adverse events were documented following the procedures. Mean dose-length product (DLP) value per injection was 665.4 ± 715.5 mGy*cm. Estimated mean effective dose per injection was 12.7 ± 12.9 mSv. Subgroup analysis between the chronologically first 10 versus subsequent 10 procedures demonstrated a clear trend towards less radiation exposure in the latter, although this difference did not reach statistical significance (DLP: 984.7 ± 903.3 vs. 436.7 ± 321.5 mGy*cm, P = 0.165; respectively). CONCLUSIONS: In this retrospective series, CT-guided transforaminal access for intrathecal injection of nusinersen was proven feasible and safe. A decrease in radiation dose over time was noted. Protocols to minimize radiation exposure are essential.

Dosimetric performance of the Elekta Unity MR-linac system: 2D and 3D dosimetry in anthropomorphic inhomogeneous geometry.

Following the clinical introduction of the Elekta Unity MR-linac, there is an urgent need for development of dosimetry protocols and tools, not affected by the presence of a magnetic field. This work presents a benchmarking methodology comprising 2D/3D passive dosimetry and involving on-couch adaptive treatment planning, a unique step in MR-linac workflows. Two identical commercially available 3D-printed head phantoms (featuring realistic bone anatomy and MR/CT contrast) were employed. One phantom incorporated a film dosimetry insert, while the second was filled with polymer gel. Gel dose-response characteristics were evaluated under the Unity irradiation and read-out conditions, using vials and a cubic container filled with gel from the same batch. Treatment plan for the head phantoms involved a hypothetical large C-shape brain lesion, partly surrounding the brainstem. An IMRT step-and-shoot 7-beam plan was employed. Pre-treatment on-couch MR-images were acquired in order for the treatment planning system to calculate the virtual couch shifts and perform adaptive planning. Absolute 2D and relative 3D measurements were compared against calculations related to both adapted and original plans. Real-time dose accumulation monitoring in the gel-filled phantom was also performed. Results from the vials and cubic container suggest that gel dose-response is linear in the dose range investigated and signal integrity is mature at the read-out timings considered. Head phantom 2D and 3D measurements agreed well with calculations with 3D gamma index passing rates above 90% in all cases, even with the most stringent criteria used (2 mm/2%). By exploiting the 3D information provided by the gel, comparison also involved DVHs, dose-volume and plan quality metrics, which also reflected the agreement between adapted and delivered plans within ±4%. No considerable discrepancies were detected between adapted and original plans. A novel methodology was developed and implemented, suitable for QA procedures in Unity. TPS calculations were validated within the experimental uncertainties involved.

Non-ionizing, laser radiation in Theranostics: The need for dosimetry and the role of Medical Physics.

The discovery of coherent laser light in 1960 shifted and expanded the biomedical applications of radiation to the non-ionizing part of the electromagnetic spectrum. As in the case of ionizing radiation, but considering the laser specific features, the effective, safe and ethically acceptable use of biomedical laser technology requires interdisciplinary collaboration between physicists, engineers and physicians. This should extend at the research, preclinical and clinical level, inspiring at this time the dynamic discipline of Medical Physics in new areas. With this work we aim to introduce the interested reader in the need of dosimetry in medical applications of laser radiation, as this field is still unexplored. After some necessary definitions, we give a brief review of the basic biophysical mechanisms of coherent light-matter interactions. The manuscript focuses on biomedical laser applications in diagnosis and therapy (i.e. in Theranostics). From the vast field of laser theranostic applications we have chosen some experimental and theoretical results - examples of quantification of the laser effect, particularly relevant to soft and hard tissue laser ablation, laser induced photodiagnosis and photodynamic therapy of cancer. These topics intend to highlight the important role of Medical Physicists in the optimization of well-established laser based clinical procedures and mainly emerge the necessity of the relevant dosimetry for each application. Finally, we hope that this effort is going to give food for thought and highlight the importance of deep knowledge of the physics behind some everyday medical applications.

Three dimensional printed electron beam modifier for total skin electron treatments.

Total Skin Electron Beam (TSEB) treatment, despite its proven effectiveness in skin malignancies, is a rather exhausting irradiation method, especially for feeble patients. In an effort to reduce treatment time by creating a clinically acceptable single TSEB field, various beam modifiers of different materials and shapes were tested. Using the TSEB immobilization device of our department and 3D printing technology, aluminum and thermoplastic modifiers were designed and constructed, according to the resulting profiles at treatment distance. Electron beam characteristics were measured and calculated both at SSD = 100 cm and at treatment level. Aluminum scatterers of the same thickness caused different modification according to the area of blocking. Aluminum modifiers reduced significantly central dose deposition for the same amount of MUs and therefore they expanded treatment time in undesirable levels. Plastic modifiers offer a good combination of field dimensions and treatment time. The final 3D printed modifier shaped the electron beam as desired resulting to a clinically acceptable 6 MeV field of 176 × 70 cm field with 10% inhomogeneity in vertical and 3% in the lateral dimension with adequate skin coverage at SSD = 400 cm. This modification offered approximately a two-minute treatment time reduction compared to the current technique. Underdosed areas appear near the edge of the field, but in regions that are far from the torso of the patient. Bremsstrahlung radiation was kept at clinically accepted levels (< 5%). This modification of the original six dual-field technique of our hospital could probably benefit fragile patients who could not easily tolerate a twenty-minute standing position without compromising the quality of their treatment.

Characterization of a novel 3D printed patient specific phantom for quality assurance in cranial stereotactic radiosurgery applications.

In single-isocenter stereotactic radiosurgery/radiotherapy (SRS/SRT) intracranial applications, multiple targets are being treated concurrently, often involving non-coplanar arcs, small photon beams and steep dose gradients. In search for more rigorous quality assurance protocols, this work presents and evaluates a novel methodology for patient-specific pre-treatment plan verification, utilizing 3D printing technology. In a patient's planning CT scan, the external contour and bone structures were segmented and 3D-printed using high-density bone-mimicking material. The resulting head phantom was filled with water while a film dosimetry insert was incorporated. Patient and phantom CT image series were fused and inspected for anatomical coherence. HUs and corresponding densities were compared in several anatomical regions within the head. Furthermore, the level of patient-to-phantom dosimetric equivalence was evaluated both computationally and experimentally. A single-isocenter multi-focal SRS treatment plan was prepared, while dose distributions were calculated on both CT image series, using identical calculation parameters. Phantom- and patient-derived dose distributions were compared in terms of isolines, DVHs, dose-volume metrics and 3D gamma index (GI) analysis. The phantom was treated as if the real patient and film measurements were compared against the patient-derived calculated dose distribution. Visual inspection of the fused CT images suggests excellent geometric similarity between phantom and patient, also confirmed using similarity indices. HUs and densities agreed within one standard deviation except for the skin (modeled as 'bone') and sinuses (water-filled). GI comparison between the calculated distributions resulted in passing rates better than 97% (1%/1 mm). DVHs and dose-volume metrics were also in satisfying agreement. In addition to serving as a feasibility proof-of-concept, experimental absolute film dosimetry verified the computational study results. GI passing rates were above 90%. Results of this work suggest that employing the presented methodology, patient-equivalent phantoms (except for the skin and sinuses areas) can be produced, enabling literally patient-specific pre-treatment plan verification in intracranial applications.

Patient-specific dosimetry in peptide receptor radionuclide therapy: a clinical review.

Neuroendocrine tumours (NETs) belong to a relatively rare class of neoplasms. Nonetheless, their prevalence has increased significantly during the last decades. Peptide receptor radionuclide therapy (PRRT) is a relatively new treatment approach for inoperable or metastasised NETs. The therapeutic effect is based on the binding of radiolabelled somatostatin analogue peptides with NETs' somatostatin receptors, resulting in internal irradiation of tumours. Pre-therapeutic patient-specific dosimetry is essential to ensure that a treatment course has high levels of safety and efficacy. This paper reviews the methods applied for PRRT dosimetry, as well as the dosimetric results presented in the literature. Focus is given on data concerning the therapeutic somatostatin analogue radiopeptides (111)In-[DTPA(0),D-Phe(1)]-octreotide ((111)In-DTPA-octreotide), (90)Y-[DOTA(0),Tyr(3)]-octreotide ((90)Y-DOTATOC) and (177)Lu-[DOTA(0),Tyr(3),Thr(8)]-octreotide ((177)Lu-DOTATATE). Following the Medical Internal Radiation Dose (MIRD) Committee formalism, dosimetric analysis demonstrates large interpatient variability in tumour and organ uptake, with kidneys and bone marrow being the critical organs. The results are dependent on the image acquisition and processing protocol, as well as the dosimetric imaging radiopharmaceutical.

Using "iDose4" iterative reconstruction algorithm in adults' chest-abdomen-pelvis CT examinations: effect on image quality in relation to patient radiation exposure.

OBJECTIVE: The aim of this study is to examine the effect of iDose4 hybrid iterative reconstruction algorithm (Philips Healthcare, Cleveland, OH) on radiation dose and image quality in chest­abdomen­pelvis (CAP) CT scanning of adult patients. METHODS: CAP CT examinations were performed on 99 patients with the use of the "old standard" protocol performing filtered back projection reconstruction algorithm (FBP protocol) and on 84 patients with the use of iDose4 protocol on a 64-multidetector CT. Patients were subdivided into three weight groups (Group 1, 41­60kg; Group 2, 61­90kg; and Group 3, .90kg). Volume CT dose index and dose length product (DLP) were recorded, while effective dose was calculated from DLP measurements. Objective image noise, signal-to-noise ratio and contrast-to-noise ratio were calculated. Two radiologists reviewed images to evaluate image quality. RESULTS: Compared with the FBP protocol, there was an overall 46.5% significant decrease in effective dose with the use of iDose4 protocol. CONCLUSION: Objective image quality was higher in iDose4 images than in FBP images. Subjective image noise, sharpness, contrast and diagnostic confidence scores tended to be better for iDose4 protocol at the decreased radiation exposure level. Artefacts were minor for both protocols. ADVANCES IN KNOWLEDGE: Our results suggest that the iterative acquisition protocol provides great potential for reducing radiation exposure and maintaining or improving image quality in CAP CT examinations.

Microwave hyperthermia in conjunction with radiotherapy in superficial tumours: correlation of thermal parameters with tumour regression / Hipertermia de microonda de conjunto con radioterapia en los tumores superficiales: correlación de los parámetros térmicos con la regresión del tumor

OBJECTIVE: The aim of the present study is to evaluate the correlation between the thermal parameters of hyperthermia and the clinical outcome in patients with superficial tumours. METHODS: In this study, 20 patients were included with either submandibular lymph nodes from head and neck cancer, or breast cancer relapses post-mastectomy. They were treated with radiation in combination with one session of433 MHz microwave hyperthermia (1 hour, 42.5 ºC-46 ºC). The dose of irradiation ranged from 54 to 60 Gy. The thermal parameters calculated were the minimum volume temperature, the maximum volume temperature and the time interval where the volume temperature was greater than 44 ºC. RESULTS: All patients responded positively to the combined treatment and 60% of the patients showed a complete response. Of the three parameters tested, the only parameter that was found to correlate with the reduction of the tumour diameter was the time with volume temperatures greater than 44 ºC (p < 0.001, Spearman rho). No moderate toxicity was observed. CONCLUSION: Microwave heating should be over 44 ºC for favourable treatment response, when combined with radiotherapy. More patients are needed to confirm the above results.

OJETIVO: El objetivo del presente estudio es evaluar la correlación entre los parámetros térmicos de la hipertermia y el resultado clínico en pacientes con tumores superficiales. MÉTODO: En este estudio, se incluyeron 20 pacientes con ganglios linfáticos submandibulares de cáncer de cabeza y cuello, o post-mastectomía por recidivas de cáncer de mama. Los pacientes fueron tratados con radiación en combinación con una sesión de hipertermia de microondas de 433 MHz (1 hora, 42.5 ºC-46 ºC). La dosis de irradiación osciló entre 54 y 60 Gy. Los parámetros térmicos calculados fueron la temperatura de volumen mínimo, la temperatura de volumen máximo y el intervalo de tiempo donde el volumen de la temperatura fue superior a 44 ºC. RESULTADOS: Todos los pacientes respondieron positivamente al tratamiento combinado y el 60% de los pacientes demostrados una respuesta completa. De los tres parámetros probados, el único parámetro que se comprobó que se correlaciona con la reducción del diámetro del tumor fue el tiempo con temperaturas de volumen superiores a 44 ºC (p < 0.001, rho de Spearman). No se observó ninguna toxicidad moderada. CONCLUSIÓN: Calentamiento por microondas debe estar por encima de 44 ºC para que la respuesta sea favorable al tratamiento en combinación con radioterapia. Se requieren más pacientes para confirmar los resultados anteriores.

Effective and ovarian dose in PA conventional and rotational 3D hysterosalpingography examinations.

The purpose of this study was to compare effective and ovarian doses (E and OD, respectively) in hysterosalpingography (HSG) examinations performed with conventional posterioanterior (PA) projections and rotational 3D (3D) techniques. 29 HSG examinations (11 conventional and 18 3D), were performed using a digital C-arm angiographic system. In the conventional technique, we used posterioanterior (PA) instead of an anterioposterior (AP) projection normally used according to the international literature. All information concerning exposure conditions for each patient, were recorded. Thermoluminescent dosimeters (TLDs) were attached on the skin of each patient over the ovaries. In conventional HSGs, average values were for Dose Area Product (DAP) 0.41 Gycm(2), for Effective Dose (E) 0.15 mSv and for Ovarian Dose (OD) 0.24 mGy. In 3D-HSGs, they were 14.4 Gycm(2), 2.29 mSv and 3.96 mGy correspondingly. Patient doses in 3D-HSGs are of the same order of magnitude with those reported in the literature for conventional technique. However, they are larger compared to the conventional HSG performed with the technique we use in this specific X-ray system. E and OD are much lower with our technique where PA projection and the specific C-arm system are used in comparison with the corresponding values published in the literature for the conventional technique where the AP projection is used.

Radiotherapy in conjunction with superficial and intracavitary hyperthermia for the treatment of solid tumors: survival and thermal parameters

Hyperthermia is an effective modality for the treatment of cancer, which is mainly used in conjunction with radiotherapy as this combined treatment offers a better clinical outcome. There are many ways that hyperthermia can be applied and depends on the kind of tumor of the patients. The great advantage of this method is that it is tolerable for the majority of patients without severe toxicity. Many clinical trials have been realized in order to prove that hyperthermia in addition to radiotherapy offers an advantage in the survival and local control of patients in comparison to radiotherapy alone. Many studies have also investigated if exists any correlation between the thermal parameters of hyperthermia and the clinical outcome. This is a review of these studies and it concerns superficial hyperthermia for superficial tumors-melanoma, head and neck, breast cancer-and intracavitary hyperthermia for rectal cancer, esophageal cancer and prostate carcinoma (AU)

Radiotherapy in conjunction with superficial and intracavitary hyperthermia for the treatment of solid tumors: survival and thermal parameters.

Hyperthermia is an effective modality for the treatment of cancer, which is mainly used in conjunction with radiotherapy as this combined treatment offers a better clinical outcome. There are many ways that hyperthermia can be applied and depends on the kind of tumor of the patients. The great advantage of this method is that it is tolerable for the majority of patients without severe toxicity. Many clinical trials have been realized in order to prove that hyperthermia in addition to radiotherapy offers an advantage in the survival and local control of patients in comparison to radiotherapy alone. Many studies have also investigated if exists any correlation between the thermal parameters of hyperthermia and the clinical outcome. This is a review of these studies and it concerns superficial hyperthermia for superficial tumors-melanoma, head and neck, breast cancer-and intracavitary hyperthermia for rectal cancer, esophageal cancer and prostate carcinoma.

Microwave hyperthermia in conjunction with radiotherapy in superficial tumours: correlation of thermal parameters with tumour regression.

OBJECTIVE: The aim of the present study is to evaluate the correlation between the thermal parameters of hyperthermia and the clinical outcome in patients with superficial tumours. METHODS: In this study, 20 patients were included with either submandibular lymph nodes from head and neck cancer, or breast cancer relapses post-mastectomy. They were treated with radiation in combination with one session of 433 MHz microwave hyperthermia (1 hour, 42.5 °C-46 °C). The dose of irradiation ranged from 54 to 60 Gy. The thermal parameters calculated were the minimum volume temperature, the maximum volume temperature and the time interval where the volume temperature was greater than 44 °C. RESULTS: All patients responded positively to the combined treatment and 60% of the patients showed a complete response. Of the three parameters tested, the only parameter that was found to correlate with the reduction of the tumour diameter was the time with volume temperatures greater than 44 °C (p < 0.001, Spearman rho). No moderate toxicity was observed. CONCLUSION: Microwave heating should be over 44 °C for favourable treatment response, when combined with radiotherapy. More patients are needed to confirm the above results.

Radiation exposure of the operator during cardiac catheter ablation procedures.

Radiation exposure of the operator during cardiac catheter ablation procedures was assessed for an experienced cardiologist adopting various measures of radiation protection and utilised electroanatomic navigation. Chip thermoluminescent dosemeters were placed at the eyes, chest, wrists and legs of the operator. The ranges of fluoroscopy time and air kerma area product values associated with cardiac ablation procedures were wide (6.3-48.3 min and 1.7-80.3 Gy cm(2), respectively). The measured median radiation doses per procedure for each monitored position were 23.6 and 21.3 µSv to the left and right wrists, respectively, 25.3 and 30.4 µSv to the left and right legs, respectively. The doses to the eyes were below the minimum detectable dose of 9 µSv. The estimated median effective dose was 22.5 µSv. Considering the actual workload of the operator, the calculated annual doses to the hands, legs and eyes, as well as the annual effective dose, were all below the corresponding limits. The findings of this study indicate that cardiac ablation procedures performed at a modern laboratory do not impose a high radiation hazard to the operator when radiation protection measures are routinely adopted.

First application of total skin electron beam irradiation in Greece: setup, measurements and dosimetry.

Total Skin Electron Beam (TSEB) irradiation is considered as the treatment of choice for cutaneous T-cell lymphoma internationally, for either curative purposes or palliative care. An attempt for the first application of this external radiation therapy technique in Greece took place at the Radiation Therapy Unit of 2(nd) Department of Radiology of University of Athens at University General Hospital "Attikon". TSEB modality was developed on a linear accelerator VARIAN Clinac 2100C. To create a uniform and sufficiently large field (≈200 cm × 80 cm) at SSD=380 cm, two symmetrical 6 MeV electron beams are combined with 17.5° tilts concerning the horizontal direction. An immobilization system was constructed to support patient during treatment and to modulate the composite electron field. Irradiation procedure demands a standing patient that takes, in total, six treatment positions. For the confirmation of treatment suitability and the determination of physical features of the clinical electron field, specific measurements were carried out using a parallel-plate ionization chamber and TLDs at water equivalent plastic and anthropomorphic phantoms. Measurements at the referred conditions showed a homogeneous total field with intensity variation of ±2% in the longitudinal axis and ±4% at horizontal axis. The mean energy of the composite field (E¯(o)) is 3.4 MeV, the most probable energy (E(p,0)) is 4.4 MeV and the half-value depth in water (R(50)) is 1.5 g/cm(2). The maximum X-ray background of the TSEB field is 2.1% at head and feet. The above results lead us to conclude that TSEB treatment using "Six-dual-field" technique can be applied in our department safely.

Patient radiation doses in cardiac computed tomography: comparison of published results with prospective and retrospective acquisition.

Prospective ECG triggering has the potential of reducing radiation exposure while maintaining diagnostic accuracy of cardiac computed tomography (CT). The aim of this study is to review patient radiation doses associated with coronary artery calcium scoring (CACS) and CT coronary angiography (CTCA) and to compare results between prospective and retrospective acquisition schemes. Patient radiation doses from CACS and CTCA were extracted from 67 relevant studies. Mean effective dose for CACS and CTCA with prospective ECG triggering is significantly lower than retrospective acquisition, 0.9±0.4 vs. 3.1±1.4 mSv, p < 0.001, and 3.4±1.4 vs. 11.1±5.4 mSv, p < 0.001, respectively. In both cardiac CT examinations, application of dose modulation techniques result in significantly lower doses in retrospective schemes, however, even with dose modulation, retrospective acquisition is associated with significantly higher doses than prospective acquisition. The number of slices acquired per rotation and the number of X-ray sources of the CT scanner (single or dual source) do not have a significant effect on patient dose.

Adult patient radiation doses from non-cardiac CT examinations: a review of published results.

OBJECTIVES: CT is a valuable tool in diagnostic radiology but it is also associated with higher patient radiation doses compared with planar radiography. The aim of this article is to review patient dose for the most common types of CT examinations reported during the past 19 years. METHODS: Reported dosimetric quantities were compared with the European diagnostic reference levels (DRLs). Effective doses were assessed with respect to the publication year and scanner technology (i.e. single-slice vs multislice). RESULTS: Considerable variation of reported values among studies was attributed to variations in both examination protocol and scanner design. Median weighted CT dose index (CTDI(w)) and dose length product (DLP) are below the proposed DRLs; however, for individual studies the DRLs are exceeded. Median reported effective doses for the most frequent CT examinations were: head, 1.9 mSv (0.3-8.2 mSv); chest, 7.5 mSv (0.3-26.0 mSv); abdomen, 7.9 mSv (1.4-31.2 mSv); and pelvis, 7.6 mSv (2.5-36.5 mSv). CONCLUSION: The introduction of mechanisms for dose reduction resulted in significantly lower patient effective doses for CT examinations of the head, chest and abdomen reported by studies published after 1995. Owing to the limited number of studies reporting patient doses for multislice CT examinations the statistical power to detect differences with single-slice scanners is not yet adequate.

Clinical implementation of total skin electron beam (TSEB) therapy: a review of the relevant literature.

Total skin electron beam therapy has been in medical service since the middle of the last century in order to confront rare skin malignancies. Since then various techniques have been developed, all aiming at better clinical results in conjunction with less post-irradiation complications. In this article every available technique is presented in addition to physical parameters of technique establishment and common dose fractionation. This study also revealed the preference of the majority of institutes the last 20 years in "six dual field technique" at a high dose rate, which is a safe and effective treatment.

Occupational radiation doses to the extremities and the eyes in interventional radiology and cardiology procedures.

OBJECTIVES: The aim of this study was to determine occupational dose levels in interventional radiology and cardiology procedures. METHODS: The study covered a sample of 25 procedures and monitored occupational dose for all laboratory personnel. Each individual wore eight thermoluminescent dosemeters next to the eyes, wrists, fingers and legs during each procedure. Radiation protection shields used in each procedure were recorded. RESULTS: The highest doses per procedure were recorded for interventionists at the left wrist (average 485 µSv, maximum 5239 µSv) and left finger (average 324 µSv, maximum 2877 µSv), whereas lower doses were recorded for the legs (average 124 µSv, maximum 1959 µSv) and the eyes (average 64 µSv, maximum 1129 µSv). Doses to the assisting nurses during the intervention were considerably lower; the highest doses were recorded at the wrists (average 26 µSv, maximum 41 µSv) and legs (average 18 µSv, maximum 22 µSv), whereas doses to the eyes were minimal (average 4 µSv, maximum 16 µSv). Occupational doses normalised to kerma area product (KAP) ranged from 11.9 to 117.3 µSv/1000 cGy cm² and KAP was poorly correlated to the interventionists' extremity doses. CONCLUSION: Calculation of the dose burden for interventionists considering the actual number of procedures performed annually revealed that dose limits for the extremities and the lenses of the eyes were not exceeded. However, there are cases in which high doses have been recorded and this can lead to exceeding the dose limits when bad practices are followed and the radiation protection tools are not properly used.