Recommendations for the use of active personal dosemeters (APDs) in interventional workplaces in hospitals.

Occupational radiation doses from interventional procedures have the potential to be relatively high. The requirement to optimise these doses encourages the use of electronic or active personal dosimeters (APDs) which are now increasingly used in hospitals. They are typically used in tandem with a routine passive dosimetry monitoring programme, with APDs used for real-time readings, for training purposes and when new imaging technology is introduced. However, there are limitations when using APDs. A survey in hospitals to identify issues related to the use of APDs was recently completed, along with an extensive series of APD tests by the EURADOS Working Group 12 on Dosimetry for Medical Imaging. The aim of this review paper is to summarise the state of the art regarding the use of APDs. We also used the results of our survey and our tests to develop a set of recommendations for the use of APDs in the clinical interventional radiology/cardiology settings, and draw attention to some of the current challenges.

THE USE OF ACTIVE PERSONAL DOSEMETERS IN INTERVENTIONAL WORKPLACES IN HOSPITALS: COMPARISON BETWEEN ACTIVE AND PASSIVE DOSEMETERS WORN SIMULTANEOUSLY BY MEDICAL STAFF.

Medical staff in interventional procedures are among the professionals with the highest occupational doses. Active personal dosemeters (APDs) can help in optimizing the exposure during interventional procedures. However, there can be problems when using APDs during interventional procedures, due to the specific energy and angular distribution of the radiation field and because of the pulsed nature of the radiation. Many parameters like the type of interventional procedure, personal habits and working techniques, protection tools used and X-ray field characteristics influence the occupational exposure and the scattered radiation around the patient. In this paper, we compare the results from three types of APDs with a passive personal dosimetry system while being used in real clinical environment by the interventional staff. The results show that there is a large spread in the ratios of the passive and active devices.

EURADOS 2016 INTERCOMPARISON EXERCISE OF EYE LENS DOSEMETERS.

In the context of a new annual eye lens dose limit for occupational exposure equal to 20 mSv, European Radiation Dosimetry Group (EURADOS) organized an intercomparison dedicated to eye lens dosemeters, including photon and beta radiations. The objective was to complete the first intercomparison recently organized by EURADOS for photons and to update the overview of eye lens dosemeters available in Europe. The dosemeters provided by the 22 participants coming from 12 countries were all composed of thermoluminescent detectors. The dosemeters were irradiated with photon and beta fields defined in relevant standards. The results, provided by participants in terms of Hp(3), were compared to the reference delivered doses. Results are globally satisfactory for photons since 90% of the data are in accordance to the ISO 14146 standard requirements. The respective values for betas stress the fact that dosemeters designed for Hp(0.07) are not suitable to monitor the eye lens dose in case of betas.

Establishing the European diagnostic reference levels for interventional cardiology.

Interventional cardiac procedures may be associated with high patient doses and therefore require special attention to protect the patients from radiation injuries such as skin erythema, cardiovascular tissue reactions or radiation-induced cancer. In this study, patient exposure data is collected from 13 countries (37 clinics and nearly 50 interventional rooms) and for 10 different procedures. Dose data was collected from a total of 14,922 interventional cardiology procedures. Based on these data European diagnostic reference levels (DRL) for air kerma-area product are suggested for coronary angiography (CA, DRL = 35 Gy cm2), percutaneous coronary intervention (PCI, 85 Gy cm2), transcatheter aortic valve implantation (TAVI, 130 Gy cm2), electrophysiological procedures (12 Gy cm2) and pacemaker implantations. Pacemaker implantations were further divided into single-chamber (2.5 Gy cm2) and dual chamber (3.5 Gy cm2) procedures and implantations of cardiac resynchronization therapy pacemaker (18 Gy cm2). Results show that relatively new techniques such as TAVI and treatment of chronic total occlusion (CTO) often produce relatively high doses, and thus emphasises the need for use of an optimization tool such as DRL to assist in reducing patient exposure. The generic DRL presented here facilitate comparison of patient exposure in interventional cardiology.

Radiation-Induced Lens Opacities among Interventional Cardiologists: Retrospective Assessment of Cumulative Eye Lens Doses.

This study describes the retrospective lens dose calculation methods developed and applied within the European epidemiological study on radiation-induced lens opacities among interventional cardiologists. While one approach focuses on self-reported data regarding working practice in combination with available procedure-specific eye lens dose values, the second approach focuses on the conversion of the individual whole-body dose to eye lens dose. In contrast with usual dose reconstruction methods within an epidemiological study, a protocol is applied resulting in an individual distribution of possible cumulative lens doses for each recruited cardiologist, rather than a single dose estimate. In this way, the uncertainty in the dose estimate (from measurement uncertainty and variability among cardiologists) is represented for each individual. Eye lens dose and whole-body dose measurements have been performed in clinical practice to validate both methods, and it was concluded that both produce acceptable results in the framework of a dose-risk evaluation study. Optimal results were obtained for the dose to the left eye using procedure-specific lens dose data in combination with information collected on working practice. This method has been applied to 421 interventional cardiologists resulting in a median cumulative eye lens dose of 15.1 cSv for the left eye and 11.4 cSv for the right eye. From the individual cumulative eye lens dose distributions obtained for each cardiologist, maxima up to 9-10 Sv were observed, although with low probability. Since whole-body dose values above the lead apron are available for only a small fraction of the cohort and in many cases not for the entire working career, the second method has only been used to benchmark the results from the first approach. This study succeeded in improving the retrospective calculation of cumulative eye lens doses in the framework of radiation-induced risk assessment of lens opacities, but it remains dependent on self-reported information, which is not always reliable for early years. However, the calculation tools developed can also be used to make an assessment of the eye lens dose in current practice.

Effectiveness of pelvic lead blanket to reduce the doses to eye lens and hands of interventional cardiologists and assistant nurses.

The aim of the present study is to analyse quantitatively the potential reduction of doses to the eye lens and the hands of an operator and a nurse by the use of a pelvic lead blanket during coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA) procedures. Thermoluminescent dosimeters were used to assess dose levels to the left eye lens and fingers on both hands of both physician and nurses during single procedures performed with or without the lead blanket. The measurements were carried out at one medical centre and include dosimetric data from 100 procedures. Additional measurements including physician's and patient's doses were made on phantoms in the laboratory. In order to determine the reduction potential of the lead blanket, the doses normalized to DAP (Dose-Area Product) corresponding to the same position of dosimeter were compared against each other for both procedure categories (with and without protection). There was no statistically significant decrease observed in physicians' and nurses' eye lens doses, nor in doses normalized to DAP due to the use of the lead pelvic shield in clinic. However, some trend in reducing the eye lens doses by this shield can be observed. Regarding finger doses, the differences are statistically significant but only for physicians. The mean DAP-normalised doses to the eye lens and left and right finger of physicians, in the presence of a ceiling-suspended transparent lead shield, were 2.24e-5 ± 1.41e-5 mSv/µGym2, 2.31e-4 ± 1.21e-4 mSv/µGym2, and 2.60e-5 ± 1.57e-5 mSv/µGym2 for standard procedures performed without the lead blanket, and 1.77e-5 ± 1.17e-5 mSv/µGym2, 1.70e-4 ± 1.01e-4 mSv/µGym2, and 1.86e-5 ± 1.13e-5 mSv/µGym2 for procedures performed with it. A comparison of the results from the laboratory and the clinic shows that they are consistent regarding the eye lens, while for fingers it suggests that the dose reduction properties of the lead shield are related to the physician's work technique and both patient and lead blanket sizes or its positioning. The highest degree of reduction is observed for cranial and caudal projections together with the use of a patient-adjustable lead blanket; about a 2-fold decrease in finger doses is expected for optimum conditions. However, the laboratory measurements suggest that the use of lead blanket might slightly increase the patient dose, but only when specific projections are constantly used. This limitation should be considered by cardiologists during clinical work if this protection is used. In the light of the presented results, the ceiling-suspended transparent lead shield and the lead glasses seem to be the preferred way to reduce the doses to the eye lens, compared to the lead blanket.

First Report of Sclerotinia Stem Blight Caused by Sclerotinia trifoliorum on Trifolium ambiguum in Poland.

Kura clover (Trifolium ambiguum M. Bieb.), a rhizomatous, persistent legume native to the Caucasus region, has received recent attention in North America and New Zealand as a pasture and silage crop. It is reported to be resistant to most pathogens affecting other clovers, including Sclerotinia trifoliorum Eriks. (3,4), one of the most destructive pathogens of clovers in northern Europe. Kura clover (cv. KTA202) was established in May 2009 near Mochelek, Poland (53° 13' N, 17° 51' E) on a Luvisol soil. By May 2011, 70% of plants grown in an experimental field (350 m2) had died, and 20% of the remaining plants were yellow and wilted. At crowns and the lower stem regions, wet, brown lesions with delicate white mycelium were observed. Lesion development was followed by death of the entire plant in a few days. By early June, only a few asymptomatic plants per square meter remained in the field. Tissue fragments of 20 symptomatic plants were surface-sterilized with 1% NaOCl for 1 min and plated on potato dextrose agar (PDA). A fungus with morphological characteristics of S. trifoliorum was consistently isolated. DNA isolation from sclerotia was performed with the DNeasy Plant Mini Kit (Qiagen, USA). Amplification and sequencing of the ITS region of rDNA was performed with primers ITS1/ITS4. NCBI Blast analysis of the 542-bp segment showed a 99% homology with most of S. trifoliorum and S. sclerotiorum strains in GenBank (e.g., AY547267.1 and EU082466.1). Sequence of isolate St0211TA was deposited in GenBank (Accession No. JQ743329). To determine growth rate of hyphae, morphology, and dimensions of sclerotia, colonies were grown in three replications on PDA at 20 ± 1°C in the dark. S. trifoliorum (CBS 122377) and S. sclerotiorum from our local collection were used as controls. Mean growth rate of S. trifoliorum isolates (20.5 mm/day) was slower compared to S. sclerotiorum (32.3 mm/day). Sclerotia began to form on delicate and smooth mycelium of S. trifoliorum on the entire surface of the plate in 7 to 8 days. Sclerotial size on day 28 was 2.0 to 9.0 × 2.0 to 7.0 mm (average 4.2 × 3.6 mm). Ultimately, the identification of S. trifoliorum was confirmed on the basis of ascospore morphology. Apothecia grew from sclerotia in wet sand at 12°C after 12 weeks. Asci contained dimorphic ascospores: four larger 13.0 to 16.0 × 6.0 to 9.0 mm (average 14.1 × 7.4 µm) and four smaller 10.0 to 12.0 × 5.4 to 6.0 mm (average 10.6 × 6.0 µm), typical for this species (1). Isolate St0511TA, which most intensively produced apothecia, was deposited in CBS (No. 133234). Koch's postulates were fulfilled by pathogenicity tests carried out on 2-week-old T. ambiguum seedlings grown in pots (6 × 30 plants), sprayed with a mycelial fragment suspension, and incubated at 15°C (2). Brown, wet spots with delicate white mycelium were observed on cotyledons after 3 days. After 5 days, approximately 10% of cotyledons were killed and mycelium appeared on stems and leaves, and after 10 days, 73% of seedlings were dead. S. trifoliorum was reisolated from all symptomatic tissues. To our knowledge, this is the first report of S. trifoliorum stem blight on T. ambiguum in the field. References: (1) E. N. Njambere et al. Plant Dis. 92:917, 2008. (2) L. H. Rhodes, Sclerotinia Crown and Stem Rot Resistance, http://www.naaic.org/stdtests/scleroti.htm , 1991. (3) A. K. Slesaravichyus et al., Selektsiya i Semenovodstvo Moskva 6:21, 1988. (4) N. L. Taylor and R. R. Smith, Adv. Agron. 63:153, 1998.

Administration of a recombinant factor Vlla in patients undergoing liver transplantation for fulminant hepatic failure.

BACKGROUND: Fulminant hepatic failure (FHF) is associated with profound clotting disturbances leading to the risk of a major blood loss during orthotopic liver transplantation (OLT). Application of a recombinant factor VIIa (rVIIa) that promptly corrects clotting abnormalities remains controversial in the OLT setting. We conducted a retrospective analysis of the effect of rVIIa on the prothrombin time (PT) and other perioperative parameters in patients transplanted for FHF in our center. MATERIALS AND METHODS: Nineteen consecutive patients (9 males/10 females) of overall mean age of 33 +/- 13 years underwent the procedure due to: Wilson's (n = 8), non-A-non-B hepatitis (n = 6) or Amanita phalloides toxicity (n = 5). All subjects received rVIIa at a mean dose of 54 +/- 16 microg/kg body weight at 10 minutes before the skin incision. The PT was measured at 15 minutes and 12 hours after injection. Data were analyzed with StatView program with P < .05 considered significant. RESULTS: Rapid correction of PT was observed in all patients: the mean PT before injection was 37 +/- 14 versus 14 +/- 3 after 15 minutes (P < .0001). Twelve hours after the injection the PT was 19 +/- 5 (P < .0001 vs before injection and P < .0007 vs 15 minutes after injection). Two patients died at 1 and 4 days after OLT. Mean red blood cell requirement was 5 +/- 4 U and fresh frozen plasma was 11 +/- 5 U. The mean operative time was 527 +/- 126 minutes and intensive care unit stay 8 +/- 9 days. None of the patients developed thromboembolic complications. CONCLUSION: Administration of rVIIa caused a rapid improvement in the PT shortly after injection. It was safe and not associated with any thromboembolic events in our series.

Liver transplantation for fulminant hepatic failure without venovenous bypass and without portacaval shunting.

Preservation of the caval vein during liver transplantation (OLT) has gained wide acceptance but portosystemic bypass or temporary portocaval shunt is still believed to be indicated in patients with fulminant hepatic failure. Herein we have described our initial experience with piggyback OLT without venovenous bypass and without portocaval shunting in five such patients. Division of the portal vein was always delayed until the native liver was completely dissected off the caval vein. The donor hepatic artery was anastomosed to the recipient aorta via an iliac interposition graft placed in the supraceliac position in two and at an infrarenal site in three patients. The ahepatic phase urinary output was low in the two patients in whom we applied supraceliac cross-clamping of the aorta. The mean ahepatic phase was 53 (45 to 67) minutes in four recipients who remained hemodynamically stable throughout surgery and prolonged to 5 hours in one patient due to a complicated supraceliac aortic anastomosis. Its repair resulted in hemodynamic instability, multiorgan failure, and death at 4 days following OLT. Four (80%) patients are alive in good condition with normal liver function after a mean of 12 (5 to 25) months of follow-up. In summary, liver transplantation for fulminant hepatic failure may be safely performed without venovenous bypass and without temporary portocaval shunting if the ahepatic phase is minimized and portal flow to the liver maintained up to the moment of hepatic excision. Arterial anastomosis with the supraceliac aorta prolongs the ahepatic phase and may impair kidney function: therefore, it should be avoided in these patients.

Rapid correction of prothrombin time after low-dose recombinant factor VIIA in patients undergoing orthotopic liver transplantation.

Orthotopic liver transplantation (OLTx) is associated with a major risk of blood loss resulting from portal hypertension, collateral circulation, and clotting disturbances. Application of a recombinant factor VIIa (rFVIIa) has been reported to promptly correct clotting abnormalities reducing the risk of intraoperative bleeding. This study included 8 patients who underwent OLTx for end-stage liver cirrhosis, with protrombin times (PT) exceeding the upper limit of normal by more than 4 seconds before surgery. All subjects were administered a small single intravenous dose of rFVIIa [mean 68.37 microg/kg body mass (range, 32.88-71.64)] 10 minutes prior to the skin incision. The PT was then measured 15 minutes later, following graft reperfusion, and 12 hours since drug application. All patients showed rapid correction of PT within 15 minutes after injection (median PT before injection 20.25 seconds vs 11.5 seconds after injection, P <.0001). Following the reperfusion PT was found to be prolonged again. These values are not significantly differ from those before surgery and are comparable to PT values after reperfusion in patients who did not receive rFVIIa. None of the patients developed thromboembolic complications. In conclusion, lower than recommended dose of rFVIIa caused rapid improvement in the PT shortly after injection. After reperfusion PT became prolonged again, which may account for the lack of thromboembolic complications observed in this group of patients.

[Evaluation of thyroid structure and function in patients with Turner syndromes]. / Ocena struktury i czynnosci tarczycy u chorych z zespolem Turnera.

The aim of our study was an estimation of thyroid structure and function in 37 patients with Turner syndrome aged from 19 to 60 years and in control group of healthy women. In each case the following studies were performed: cytogenetic examination, thyroid ultrasonography, serum total and free thyroid hormones, TSH, thyroglobulin (Tg), thyroid hormones binding globulin (TBG), antithyroglobulin and antithyroperoxidase antibodies (anti-Tg and anti-TPO) levels. In Turner syndrome ultrasonographic volume of the thyroid was significantly lower than in control group (11.03 vs 16.98 cm3). Abnormalities of thyroid function were found in 8 (22%) studied cases (subclinical primary hypothyroidism in 16%, full-clinical primary hypothyroidism in 3% and hyperthyroidism in course of Graves disease in 3%). Serum elevated antithyroid antibodies were present in 62% cases of Turner syndrome and were significantly higher than in control group (16%). In Turner syndrome thyroid diseases are more frequent than in healthy population. Every patient with Turner syndrome needs routine diagnostics of the thyroid structure and function.