Personal dose equivalent Hp(0.07) during 68Ga-DOTA-TATE production procedures.

This work presents the exposure of hands of the personnel of a nuclear medicine department who prepare and administer 68Ga-DOTA-TATE. Dosimetry measurements were performed during three 1-week sessions, for nine production procedures. A total of 360 measurements were made by using high-sensitivity MCP-N thermoluminescent detectors. Annealed detectors were and vacuum-packed in foil and then placed on each fingertip of both hands of five radiochemists and four nurses (one detector for one fingertip). The greatest exposure to ionizing radiation was found on the non-dominant left hand of radiochemists and nurses. A maximum Hp(0.07)/A value of 49.36 ± 4.95 mSv/GBq was registered for radiochemists during the 68 Ga-DOTA-DATE activity dispensing procedure. For nurses performing the radiopharmaceutical injection procedure, a corresponding maximum value of 1.28 ± 0.13 mSv/GBq was measured, while the mean value for all the nurses was 0.38 mSv/GBq. The dispensing procedure accounted for approximately 60% of the total exposure of radiochemists' fingertips. Based on the results obtained it is recommended that a ring dosimeter should be routinely placed on the middle finger of the non-dominant hand of radiochemists and nurses. Furthermore, it is proposed to systematically train workers in handling open sources of ionizing radiation, with the aim of reducing the required handling time.

68Ga-DOTA-TATE-a source of eye lens exposure for nuclear medicine department workers.

INTRODUCTION: Obtaining 68Ga-DOTA-TATE (a radioconjugate consisting of the somatostatin analogue tyrosine-3-octreotate (Tyr3-octreotate or TATE) labelled with the positron emission tomography tracer gallium 68Ga via the macrocyclic chelating agent dodecanetetraacetic acid (DOTA)) is a complex process and, as with any radiopharmaceutical whose basis is a short-lived radionuclide generator, it is based on a sequence of procedures beginning from the 68Ge/68Ga generator elution, labelling ligands with a radioisotope, dispensing doses of 68Ga-DOTA-TATE for patients and finally injection of the preparation to patients. The complexity of this process may contribute to an increased exposure of eye lenses of the staff who perform the above-mentioned procedures, which is especially important at a time when the dose limit on the lens of the eye is being reduced from 150 to 20 mSv yr-1. OBJECTIVE: The work presents the exposure of eye lenses of the personnel of a nuclear medicine department who prepare and inject 68Ga-DOTA-TATE. MATERIALS AND METHODS: Radiochemists and nurses were monitored by dosimetry measurements with thermoluminescent detectors (TLDs). RESULTS: The values of Hp(3)/A-normalised personal eye dose equivalent recorded in the group of radiochemists during the procedure of dispensing the doses of 68Ga-DOTA-TATE for patients exceeded the value of 274 µSv/GBq. CONCLUSIONS: The estimated annual Hp(3) values may exceed 20 mSv, which is particularly important due to the fact that procedures using the 68Ga radioactivity are only a small part of the daily professional activity of the staff, resulting from the performance of other procedures that require the use of other radioisotopes.

Is eye lens dosimetry needed in nuclear medicine?

INTRODUCTION: The exact level of exposure experienced by nuclear medicine personnel, whose work often requires performing manual procedures involving radioactive isotopes, is associated with the form of radiation source used. The variety of radionuclides and medical procedures, and the yearly increase in the number of patients, as well as the change of the individual dose limit for the lens of the eye from a value of 150 mSv yr-1 to 20 mSv yr-1, mean that issues of eye lens routine dosimetry become interesting from the radiation protection point of view. OBJECTIVE: This paper presents an analysis of the exposure of the eye lenses of nuclear medicine department personnel, as well as those of personnel in the facilities that produce radiopharmaceuticals for the purpose of diagnosis by positron emission tomography, from the viewpoint of the advisability of routine eye lens exposure monitoring, taking into account changes in the dose limit for the lens of the eye. MATERIALS AND METHODS: The paper considers the two most commonly used radionuclides for diagnostic purposes 99mTc, 18F, and-for therapeutic purposes-131I. Dose measurements were made using thermoluminescent detectors. RESULTS: The estimated exposure analysis identifies the cases when the maximum annual value of the personal dose equivalent, in terms of Hp(3), exceeds threefold the new limit value (20 mSv yr-1). CONCLUSIONS: It is recommended that Hp(3) doses be routinely monitored in the group of radiopharmacists who label pharmaceuticals with the radionuclide 99mTc and in chemists working in 18F-FDG quality control departments in production units, where this is carried out manually.

Hand exposure of nuclear medicine workers during administration of radioiodine.

(131)I has been widely used in nuclear medicine for many years, particularly in the form of iodide for the diagnosis and therapy of thyroid cancer and other thyroid diseases. Manual dispensing of radioiodine-based radiopharmaceuticals results in potentially significant radiation doses to the hands of nuclear medicine personnel performing this task. This article reports the results of thermoluminescent dosemeter-based measurement of radiation doses at various points on the hands of personnel dispensing radioiodine radiopharmaceuticals.

Hand exposure to ionising radiation of nuclear medicine workers.

The specific nature of work in nuclear medicine departments involves the use of isotopes and handling procedures, which contribute to the considerable value of an equivalent dose received, in particular, by the fingertips. Standard nuclear medicine department uses ring dosemeters placed usually at the base of the middle finger. The main aim of the study was to find out whether a relationship exists between the doses recorded by thermoluminescent detectors placed at various locations on the radiopharmacists' hands and the doses recorded by the ring detectors, and to determine the character of that relationship. The correction factor represents a correction value to be used to calculate the doses which might be received by locations on the hand from the dose recorded by the ring dosemeter. The dose recorded by the ring dosemeter is on the average five times lower than that received by the fingertips of thumb, index and middle fingers.

Sentinel node biopsy in patients with breast cancer--evaluation of exposure to radiation of medical staff.

AIM: To measure the absorbed doses of radiation to hands of medical staff performing sentinel node biopsy in breast cancer patients. METHODS: The study was conducted in 2004, during sentinel node biopsies in 13 breast cancer patients (T1/T2N0). Sentinel nodes were identified with the use of combined radiotracer/blue dye technique (lymphoscintigraphy--99mTc on albumin carrier, surgery after 24 h; blue dye; intraoperative detection of gamma radiation). Highly sensitive thermoluminescent dosimeters (TLD) made of LiF were used to assess the absorbed doses of radiation during the procedure. During lymphoscintigraphy and during surgical procedure a total of 57 TLDs was placed on different parts of hands of medical staff. RESULTS: Maximal dose recorded during lymphoscintigraphy by TLDs placed on the hands of the physician injecting the radiotracer was 164 microSv. Mean recorded doses were higher for non-dominant hand, especially for distal parts of the index finger, third finger and thumb. During the surgical procedure, TLDs placed on the hands of medical staff recorded much lower doses of radiation than during lymphoscintigraphy. The highest dose was recorded by TLD placed on the pulp of the dominant hand index finger (22 microSv) of the operating surgeon. Mean doses recorded by TLDs placed on the hands of the operating surgeon ranged from 2 to 8 microSv. The absorbed dose of radiation to hands of the scrub nurse was similar to that absorbed to hands of the operating surgeon. CONCLUSION: The maximum recorded dose during sentinel node biopsy in this study was 2200 times smaller than current 1-year dose limit.