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.

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.