Will X-ray Safety Glasses Become Mandatory for Radiological Vascular Interventions?

Radiation shielding effects of lead equivalent thickness of a radiation protective apron and distance during C-arm fluoroscopy-guided pain interventions: A randomized trial

BACKGROUND

The present study aimed to evaluate the degree of radiation shielding effects according to lead equivalent thickness and distance during C-arm fluoroscopy-guided lumbar interventions.

METHODS

The exposure time and air kerma were recorded using a fluoroscope. The effective dose (ED) was measured with and without the shielding material of the lead apron using 2 dosimeters at 2 positions. According to the lead equivalent thickness of the shielding material and distance from the side of the table, the groups were divided into 4 groups: group 1 (lead equivalent thickness 0.6 mm, distance 0 cm), group 2 (lead equivalent thickness 0.6 mm, distance 5 cm), group 3 (lead equivalent thickness 0.3 mm, distance 0 cm), and group 4 (lead equivalent thickness 0.3 mm, distance 5 cm). Mean differences such as air kerma, exposure time, ED, and ratio of EDs (ED with protector/ED without protector) were analyzed.

RESULTS

A total of 400 cases (100 cases in each group) were collected. The ratio of ED was significantly lower in groups 1 and 2 (9.18 ± 2.78% and 9.56 ± 3.29%, respectively) when compared to that of groups 3 and 4 (21.93 ± 4.19% and 21.53 ± 4.30%, respectively). The reductive effect of a 5-cm distance was 33.3% to 36.1% when comparing the ED between groups 1 and 2 and groups 3 and 4.

CONCLUSIONS

The 0.3- and 0.6-mm lead equivalent thickness protectors have a radiation attenuation effect of 78.1% to 78.5% and 90.4% to 90.8%, respectively. The 5-cm distance from the side of the table reduces radiation exposure by 33.3% to 36.1%.

Are X-ray Safety Glasses Alone Enough for Adequate Ocular Protection in Complex Radiological Interventions?

ABSTRACT

The maximum annual radiation ocular dose limit for medical staff has been reduced to 20 mSv in the current European directive 2013/59/Euratom. This multi-centric study aims at reporting the protected and unprotected eye lens doses in different fluoroscopically guided interventions and to evaluate any other factors that could influence the ocular dose. From July 2018 to July 2019, ocular radiation doses of six interventionists of four departments during complex interventions were recorded with a thermoluminescent dosimeter in front of and behind radiation protection glasses to measure the protected and unprotected doses. The position of personnel, intervention type, fluoroscopy time, total body dose and use of pre-installed protection devices like lead acrylic shields were also systematically recorded. Linear regression analysis was used to estimate the doses at 2 y and 5 y. The annual unprotected/protected ocular doses of six interventionists were 67/21, 32.7/3.3, 27.4/5.1, 7/0, 21.8/2.2, and 0/0 mSv, respectively. The unprotected dose crossed the 20-mSv annual limits for four interventionists and protected dose for one less experienced interventionist. The estimated 5-y protected ocular dose of this interventionist was 101.318 mSv (95%CI 96.066-106.57), also crossing the 5-y limit. The use of a lead acrylic shield was observed to have a significant effect in reducing ocular doses. The annual unprotected and protected ocular doses for interventionists dealing with complex interventions could cross the present permitted yearly limit. The measurement of significant protected ocular dose behind the radiation protection glasses emphasizes the additional indispensable role of pre-installed radiation protection devices and training in reducing radiation doses for complex procedures.

Neurointerventionalist and Patient Radiation Doses in Endovascular Treatment of Acute Ischemic Stroke

PURPOSE

To evaluate the patient and the neurointerventionalist radiation dose levels during endovascular treatment of acute ischemic stroke, and to analyze factors affecting doses.

MATERIALS AND METHODS

From October 2017 to January 2019, we prospectively collected patient radiation data and neurointerventionalist data from real-time dosimetry from all consecutive thrombectomies. Multivariate analysis was performed to analyze patient total dose area product (DAP) and neurointerventionalist dose variability in terms of clinical characteristics and the technical parameters of thrombectomies. Local dose reference levels (RL) were derived as the 75th percentile of the patient dose distributions.

RESULTS

A total of 179 patients were treated during the study period and included in this study. Local dose RL for thrombectomy was derived for total DAP to 34 Gy cm², cumulative air kerma of 242 mGy and fluoroscopy time of 12 min. The mean neurointerventionalist dose for thrombectomy was 7.7 ± 7.4 µSv. Height (P = 0.018), weight (P = 0.004), body mass index (P = 0.015), puncture to recanalisation (P < 0.001), fluoro time (P < 0.001), number of passes (P < 0.001), thrombolysis in cerebral infarction 2b/3 recanalisation (P = 0.034) and aspiration thrombectomy (P < 0.001) were independent factors affecting patient total DAP, whereas baseline National Institutes of Health Stroke Scale (P = 0.043), puncture to recanalisation (P = 0.003), fluoroscopy time (P = 0.009) and number of passes (P = 0.009) were factors affecting the neurointerventionalist dose.

CONCLUSION

New reference patient doses lower than those in previously published studies were defined. However, the operator's doses were higher than those in the only available study reporting on operator's dose during cerebral interventions.

Protective Efficacy of Different Ocular Radiation Protection Devices: A Phantom Study

PURPOSE

The aim of this study was to investigate the efficacy of different designs and types of ocular radiation protection devices depending on simulated varied body heights in a phantom-simulated thoracic intervention.

MATERIALS AND METHODS

A clinical angiography system with a standardized fluoroscopy protocol with an anthropomorphic chest phantom as a scattering object and optically stimulated luminescence dosimeters for measuring radiation dose were used. The dosimeters were placed at the position of eyes of an anthropomorphic head phantom simulating the examiner. The head phantom was placed on a height-adjustable stand simulating the height of the examiner from 160 to 200 cm with 10 cm increments. The dose values were then measured with no radiation protection, a weightless-like radiation protection garment, radiation protection glasses and visors.

RESULTS

The average dose reduction using radiation protection devices varied between 57.7 and 83.4% (p < 0.05) in comparison with no radiation protection. Some radiation protection glasses and visors showed a significant dose reduction for the eye lenses when the height of the examiner increased. The right eye was partially less protected, especially if the distances between the simulated examiner's head and the scatter object were small.

CONCLUSION

All the investigated protection devices showed a significant reduction in radiation exposure to the simulated examiner. For some devices, the radiation dose increased with decreasing distance to the scattering object, especially for the right eye lens.