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L K Harding

Publications and source records attributed to L K Harding.

At least 55 records · Page 3Linked to original sources
PubMed1992

Radiation doses from nuclear medicine patients to an imaging technologist: relation to ICRP recommendations for pregnant workers.

The ICRP has now recommended that the dose limit to the surface of the mother's abdomen during the declared term of pregnancy is reduced to 2 mSv. Direct measurements of the radiation dose to technologists carrying out a variety of imaging studies were made. The average dose ranged from 0.3 micro Sv for a liver scan to 5.3 micro Sv for a brain scan. Using national data for the frequency of nuclear medicine studies, a weighted average figure of 1.5 micro Sv per study was derived. A technologist could therefore perform approximately eight imaging studies per day during the declared term of her pregnancy and remain within the proposed limit. Generally, there should be no need to alter a technologist's duties during her pregnancy, and these findings should be helpful in allaying any anxiety.

Female↗
PubMed1991

1992 and all that.

Explore the source record for details and available documents.

European Union↗
PubMed1991

Radiation dose rates from paediatric patients undergoing 99Tcm investigations.

Infants or children undergoing nuclear medicine investigations may subsequently come into close contact with nurses or parents responsible for their care. In order to estimate the radiation dose to these individuals, and to formulate appropriate recommendations, dose rates were measured at distances of 0.1, 0.5 and 1.0 m from 148 paediatric patients who had undergone one of 12 99Tcm studies. The maximum dose rates of 70, 14 and 5 microSv h-1 at these distances were not greater than the corresponding maximum values found in an earlier study of adult patients. However, the maximum dose rates per unit activity of 0.5, 0.2 and 0.1 microSv h-1 MBq-1 were greater than the corresponding maximum 99Tcm adult values, consistent with a general increase of dose rate per unit activity with decrease of body weight observed in the paediatric measurements. A parent caring for and feeding a young infant is most unlikely to receive a dose equivalent of 1 mSv, and a nurse attending to one young radioactive patient is most unlikely to receive a dose equivalent in a working day of 60 microSv. The data obtained should allow radiation doses to be estimated and appropriate recommendations to be formulated for other circumstances, including any future legislative changes in dose limits or derived levels.

Adolescent↗
PubMed1990

Diffuse increase in renal uptake of technetium 99m methylene diphosphonate in association with disseminated cholangiocarcinoma.

A 48-year-old woman presented with disseminated cholangiocarcinoma and diffuse joint pain. A technetium 99m methylene diphosphonate bone scan revealed no bony abnormality, but intense bilateral renal uptake was seen. There was temporary renal impairment following imaging, but the cause of this is uncertain. An association between cholangiocarcinoma and 'hot kidneys' on bone imaging scanning has not been previously reported.

Adenoma, Bile Duct↗
PubMed1990

Quantitative imaging in the gastrointestinal tract.

Various problems are encountered in measuring gastric emptying, especially relating counts to the volume of meal remaining in the stomach. We have developed a method which has been validated against aspiration of the stomach. In gastric ulcer patients, however, the stomach is large and overlaps the bowel. Results of gastric emptying studies in patients who have had surgery for peptic ulceration show that impaired gastric emptying is related to the extent of vagotomy and pyloric surgery. We have examined the pattern of biliary excretion of iminodiacetic acid derivatives and related enterogastric reflux to the amount of bile in the stomach as determined by aspiration. However the reproducibility is only 75% probably due to day to day variation in its occurrence. The incidence of reflux in control subjects and in those with peptic ulcer is discussed, as is its relationship to the extent of vagotomy and the length of Roux-en-Y loops. Finally the diagnosis of biliary atresia using a similar radiopharmaceutical is described. It has been suggested that a high liver to heart ratio excludes the diagnosis of atresia, but we have failed to confirm this finding.

Bile Reflux↗
PubMed1990

The radiation dose to accompanying nurses, relatives and other patients in a nuclear medicine department waiting room.

The radiation dose to accompanying nurses, relatives and other patients in a nuclear medicine department waiting room was assessed at 5 min intervals by observing the seating arrangement. The total radiation dose to each person was calculated, using fixed values of dose rate per 100 MBq activity for radionuclides, and applying the inverse square law. Radioactive decay and attenuation effects due to intervening persons were also taken into account. The median radiation doses to accompanying nurses, relatives and other patients were 2.3, 2.0 and 0.2 microSv with maximum values of 17, 33 and 5 microSv respectively. In all cases, the radiation dose received by patients was less than 0.2% of the radiation dose resulting from their own investigation. Also, the maximum radiation dose received by an accompanying nurse or friend was less than 1% of their appropriate annual dose limit. Similar values were obtained with calculations based on a 15 min time interval. The radiation doses received by those in a nuclear medicine department waiting room are small, and separate waiting room facilities for radioactive patients are unnecessary.

Family↗
PubMed1990

Consistency in nuclear medicine reporting--a pilot study using bone scans.

In a pilot study of consistency in nuclear medicine reporting, a panel of three observers evaluated 60 bone scans carried out for detection of metastases. The bone scans had originated from 10 departments. Difficulties arose in evaluation of the quality of the images by the panel members because of the differing criteria each chose to adopt. This highlights the need to define strictly, in advance, the parameters to be included in quality assessment. All three panel members agreed on the lesions present in 54 out of 60 studies. The observers' consensus report showed material differences from the original departmental report in the number of lesions present in 10 out of 60 studies. Material differences in the interpretation of the study occurred between panel members in two cases and between the panel and the original report in four cases. The pilot study has shown an acceptable level of consistency in bone scan reporting in the departments contributing images. A national study assessing consistency of reporting would be difficult to organize but alternative, more local, schemes are suggested.

Bone Neoplasms↗
PubMed1990

Staff radiation doses associated with nuclear medicine procedures--a review of some recent measurements.

Despite publication of the Approved Code of Practice and the Notes for Guidance, implementation of the UK Ionising Radiation Regulations has required local interpretation by nuclear medicine departments. One problem has been the lack of data upon which decisions can be based. In the last five years we and others have made a number of measurements of radiation doses to staff relating to nuclear medicine practice. This paper collates, summarizes and comments on this information. Where possible, results have been expressed in relation to the workload of an average nuclear medicine department.

Environmental Exposure↗
PubMed1989

A postal survey of quality assurance in nuclear medicine imaging in the UK during 1988.

A questionnaire was sent to all the estimated 200 hospital departments providing nuclear medicine imaging services in the UK. Replies were received from 162 (81%). The questionnaire was brief, but covered a wide range of aspects of a nuclear medicine service. While all responses showed departments to have some quality control procedures in operation, they were often not used correctly. In most departments there appears to be scope for improvement so that departmental managers can monitor more closely the quality of service provided.

Hospital Departments↗