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A study of the relationship between patient dose and size in paediatric radiology.

Entrance doses and dose-area products have been measured for paediatric X-ray examinations in a dedicated paediatric department. Dose-area products for barium meal and micturating cystourethrogram examinations involving fluoroscopy were substantially less than results from other studies. A number of factors contribute to this, including a high gain image intensifier used without a grid, shorter screening times, smaller numbers of films, exclusive use of a 100 mm camera and careful collimation of the X-ray field. Entrance air kerma has been measured for pelvis, abdomen, chest and skull radiographs. The relationship between dosimetric quantities and an equivalent patient diameter derived from data on patient height and weight has been studied. The results show a linear relationship between the logarithm of entrance air kerma and equivalent patient diameter for radiographic examinations performed on a single X-ray unit. Application of exponential correction factors could allow entrance doses for radiographs of children of different ages to be compared with appropriate reference doses.

Adolescent↗

A study of patient radiation doses in interventional radiological procedures.

Patient radiation doses received during interventional radiological procedures can be significant. To aid in the establishment of reference dose levels, a patient dose survey has been conducted of such procedures. A total of 288 non-coronary procedures (177 classified as diagnostic and 111 as therapeutic) were accrued into the study. For each procedure, the fluoroscopy screening time and the fluoroscopic and digital radiographic dose-area products were recorded in a computer database. For example, median dose-area product values (due to fluoroscopy and digital radiography combined) of 24.2, 27.9, 69.6 and 74.7 Gy cm2 were obtained for nephrostomy, biliary stent removal/insertion, cerebral angiography and percutaneous transhepatic cholangiography procedures. While the effective dose is not an accurate measure of patient risk, it is convenient for comparing the radiological risks associated with various procedures. Effective doses were estimated from the total dose-area products. The respective median estimated effective dose values for the four procedures noted above were 3.9, 4.5, 7.0 and 12.0 mSv. While an infrequently performed procedure at this institution (n = 4 during this survey), the transjugular intrahepatic portosystemic shunt (TIPS) procedure had the greatest median dose-area product and effective dose values: 347 Gy cm2 and 55.5 mSv, respectively. Excluding the extreme case of TIPS, it was found that among commonly-performed procedures, those that are categorized as therapeutic do not necessarily present a statistically significant greater radiation risk than those which are diagnostic. Comparisons between dose-area product values obtained from this study are made with data from other interventional radiology patient dose surveys and reasons for some differences noted are discussed.

Angiography↗

Effective dose to the patient undergoing superior vena cava stent.

Metallic stents have been recently introduced for treating superior vena cava (SVC) obstruction. Dose data, in terms of dose-area product (DAP), from 44 patients referred for SVC stent placement on a digital unit have been retrospectively analysed in terms of their fluoroscopic and radiographic components. The mean DAP for the 44 examinations was 42 Gy cm2 and the effective dose was estimated to be 5.8 mSv. The fluoroscopic component was approximately 80%, with a mean screening time for these examinations of 17 min. The mean number of digital exposures was 86.

Aged↗

Influence of radiologists' sex and training on fluoroscopy doses during barium enema.

Variables influencing radiation exposure were studied using analysis of covariance in 523 double contrast barium enemas performed by 21 radiology residents (12 female, 9 male). Dose-area products (DAPs) (ns), number of exposures per patient (p < 0.05) and screening times (p < 0.05) were higher for female residents (mean 52.0 Gy cm2, 9.55 exposures and 4.02 min, respectively) than for male residents (mean 41.7 Gy cm2, 8.26 exposures and 3.20 min, respectively). The number of lectures on radiation protection attended by the resident (range 0-20) had no significant effect on these radiation-related variables. Other factors explaining these variables were patient age, diagnosis and anteroposterior thickness. Radiologists' use of ionizing radiation during fluoroscopy may be sex-related. Traditional lecture-based education on radiation protection was not effective with this group; thus, improved methods should be developed to control doses.

Adult↗

Patient and operator dose during fluoroscopic examination of swallow mechanism.

Dose-area product (DAP) measurements were made for 21 patients undergoing a modified barium swallow. The procedures were performed by a radiologist and speech and language therapist, to characterize swallowing disorders in patients with head or spinal injury, stroke, other neurological conditions or simple globus symptoms, in order to inform feeding strategies. The DAP values were used to estimate effective dose to the patient, in order to provide a measure of the radiation risk associated with the procedure. Whole body doses to operators, together with equivalent doses to extremities and eyes were also measured to inform the employer's risk assessment. Median DAP for the series was 3.5 (3.1-5.2) Gycm(2) with a corresponding effective dose to the patient of 0.85 (0.76-1.3) mSv, and a low associated risk, mainly of cancer induction, of about 1 in 16 000. The organ receiving the greatest dose was the thyroid, with a calculated median equivalent dose of 13.9 (12.3-20.7) mSv. Median screening time was 3.7 (2.5-4.3) min. Mean operator doses were 0.5 mSv equivalent dose (eyes), 0.9 mSv (extremities), and less than 0.3 mSv whole body dose. Extrapolating for an annual workload of 50 patients per year, this work will lead to annual operator doses of less than 0.6 mSv whole body dose, and approximately 1 mSv equivalent dose (eyes) and 1.8 mSv (extremities), against corresponding legal dose limits of 20 mSv, 150 mSv and 500 mSv, respectively.

Barium Sulfate↗

Gamma nails and dynamic hip screws for peritrochanteric fractures. A randomised prospective study in elderly patients.

The Gamma nail was introduced for the treatment of peritrochanteric fractures with the theoretical advantage of a load-sharing femoral component which could be implanted by a closed procedure. We report a randomised prospective study of 186 fractures treated by either the Gamma nail or a dynamic hip screw. Gamma nails were implanted with significantly shorter screening times, smaller incisions, and less intraoperative bleeding. The Gamma nail group had a shorter convalescence and earlier full weight-bearing, but there was no significant difference in mortality within six months, postoperative mobility, or hip function at review. More intra-operative complications were recorded in the Gamma nail group, mainly due to the mismatching of the femoral component of the nail to the small femurs of Chinese people. Use of a smaller modified nail reduced these complications. We conclude that with careful surgical technique and the modified femoral component, the Gamma nail is an advance in the treatment of peritrochanteric fractures.

Aged↗

Modified AFLP technique for rapid genetic characterization in plants.

The standard amplified fragment-length polymorphism (AFLP) technique was modified to develop a convenient and reliable technique for rapid genetic characterization of plants. Modifications included (i) using one restriction enzyme, one adapter molecule and primer, (ii) incorporating formamide to generate more intense and uniform bands and (iii) using agarose gel electrophoresis. Sea oats (Uniola paniculata L.), pickerel-weed (Pontederia cordata L.), Bermudagrass (Cynodon dactylon L.) and Penstemon heterophyllus Lindl. were used to determine the ability to generate adequate resolution power with both self- and cross-pollinated plant species including cultivars, ecotypes and individuals within populations. Reproducibility of bands was higher in all the AFLP experiments compared to random amplified polymorphic DNA (RAPD). Formamide with or without bovine serum albumin improved band intensities compared to dimethyl sulfoxide and the standard reaction mixture with no organic solvents. Comparison between RAPD and modified AFLP using sea-oats population samples proved that modified AFLP exhibits (i) a low number of faint bands with increased specificity of amplified bands, (ii) a significantly higher number of polymorphic loci per primer, (iii) less primer screening time, (iv) easy scoring associated with fewer faint bands and (v) greatly enhanced reproducibility. The technique described here can be applied with a high degree of accuracy for plant genetic characterization.

Plants↗

Treatment of nasolacrimal duct obstruction with polyurethane stent placement: long-term results.

OBJECTIVE: The purpose of this study was to evaluate the long-term efficacy of polyurethane stent placement in adults with nasolacrimal duct obstruction. SUBJECTS AND METHODS: Polyurethane stents were placed under fluoroscopic guidance in 52 eyes of 49 patients (mean age, 43 years) with severe epiphora due to idiopathic nasolacrimal duct obstruction. The obstruction was complete in 44 eyes and partial in eight. Clinical success was defined as complete resolution of or great improvement in the symptoms of epiphora and the patency of the lacrimal system to irrigation. Mean follow-up was 23 months (range, 14-44 months). RESULTS: Stent placement was technically successful in 50 eyes (96%). The mean fluoroscopy screening time was 2.2 min (range, 0.2-5.8 min). Two patients were lost to follow-up. Clinical success was obtained in 33 (69%) of 48 eyes. Lacrimal symptoms developed in 23 (70%) of these 33 eyes at least once during the follow-up, but these patients responded well to topical drug treatment and lacrimal irrigation. External dacryocystorhinostomy was performed in 13 eyes after failure of the stents. At surgery, lacrimal sacs were shrunken, hyperemic, and fragile in all eyes, making it difficult to anastomose with nasal mucosa. Histologic examination showed granulation tissue and chronic inflammation of the sac epithelium. CONCLUSION: The success rate of the nasolacrimal stent decreases as follow-up lengthens. After stent treatment, lacrimal symptoms frequently develop, even if the stent remains patent, and require multiple office visits and therapy. The polyurethane stent may induce a chronic inflammatory response in the lacrimal sac, which can interfere with subsequent dacryocystorhinostomy.

Adult↗

Effectiveness of two preventive interventions for coronary heart disease in primary care.

OBJECTIVES: 1. To compare a patient-centred, self-directive intervention with conventional care; 2. To evaluate longitudinal within-group changes of coronary heart disease risk. METHODS: Risk factor changes were evaluated in 110 men with high coronary heart disease risk attending a one year intervention study in general practice. The 22 participating general practice centres were randomly allocated to follow either a patient-centred, self-directive intervention or a conventional approach. RESULTS: No significant between-group differences were found in any single risk factor or in the combined risk of coronary heart disease. The improvement of total risk from screening time to conclusion of the study corresponded with changes of relative risks of CHD to 0.64 (95% CI: 0.54-0.77) and 0.65 (0.54-0.77) in the patient-centred, self-directive and the conventional care group respectively (p < 0.0001 in both groups). CONCLUSION: Everyday general practice clinical work seems as efficacious as a specific intervention method based on currently advocated behaviour change principles.

Adult↗

Baseline behavioral assessment for the new Jersey Health Wellness Promotion Act.

PURPOSE: To determine baseline use rates for health-promoting behaviors of the recently adopted New Jersey Health Wellness Promotion Act and to examine the effects of demographic and socioeconomic factors on the use of preventive services included in the Act. DESIGN: A random telephone survey of 3094 households was conducted using questions from the Behavioral Risk Factor Surveillance System supplemented by questions related to provisions of the Act. SETTING: All New Jersey households. SUBJECTS: State representative adult sample of 1246 subjects. MEASURES: Rates for getting timely screening tests, for obtaining influenza immunizations, and engaging in selected health-promoting behaviors. RESULTS: Rates for receiving recommended screening tests ranged from 0.88 for blood pressure testing to 0.29 for osteoporosis screening. According to bivariate analysis, having insurance was the most consistent determinant associated with receiving preventive services but was associated only with sigmoidoscopy, mammography, and Pap smear testing in the multivariate modeling. Reminders were significantly associated with respective screening tests. Age was positively associated with receiving the majority of tests. Gender ethnicity, education, and income affected receipt sporadically. Half the respondents were overweight and a quarter were current smokers. CONCLUSIONS: Receipt of appropriate screening tests and adoption of health-promoting behaviors fell short of desired goals. Having health insurance increased receipt rates, but was not enough to achieve usage goals. Procedure-specific reminders may improve usage rates.

Adult↗

Identification of Aedes aegypti and its respective life stages by real-time polymerase chain reaction.

An Aedes aegypti-specific, fluorogenic probe hydrolysis (Taq-Man), polymerase chain reaction assay was developed for real-time screening using a field-deployable thermocycler. Laboratory-based testing of A. aegypti, A. aegypti (Trinidad strain), Culex pipiens, Culex quinquefasciatus, Anopheles stephensi, and Ochlerotatus taeniorhynchus individual adult mosquitoes and mixed pools (n = 10) demonstrated 100% concordance in both in vitro sensitivity (six of six samples) and specificity (10 of 10 samples). A single adult A. aegypti was identified in a pool of 100 non-A. aegypti mosquitoes. The limit of detection of A. aegypti egg pools was five individual eggs. Field testing was conducted in central Honduras. An A. aegypti and Culex spp. panel of individual and mixed pools (n = 30) of adult mosquitoes, pupae, and larvae demonstrated 100% concordance in sensitivity (22 of 22 samples) and 97% concordance in specificity (29 of 30 samples), with one false-positive result. Field testing of an A. aegypti and Culex spp. blind panel (n = 16) consisting of individual and mixed pools of adult mosquitoes, pupae, and larvae demonstrated 90% concordance in sensitivity (nine of 10 samples) and 88% concordance in specificity (14 of 16 samples).

Aedes↗

[Percutaneous closure of patent arterial ducts with occluding spring coils].

In recent years percutaneous closure of small and medium-sized patent arterial ducts has been achieved using occluding spring coils. We describe our experience in 93 patients with this technique, using a snare to facilitate the procedure in most. All patients had a clinically apparent patent arterial duct and had undergone attempts at transcatheter closure at a mean age of 6.8 years. In 1, the duct was a residual lesion following surgical ligation, and in 5 it was a residual following attempted closure with the Rashkind double-umbrella. The mean narrowest diameter of the ducts was 2.1 mm. In our 93 patients implantation was successful in 92 (99%), using 1 coil (82 patients), or 2 (10 patients), and in 1 by a combination of a double-umbrella device and an occluding spring coil. The mean fluoroscopic screening time for the whole group was 22.8 minutes, which decreased to 16.8 minutes in the last 50 patients. The coil embolized in 7 patients, but was retrieved in 6 and the ducts were subsequently occluded with another coil. In 1 patient the coil was left in a distal small branch of the left pulmonary artery and the duct was successfully occluded with a double-umbrella. Color-Doppler echocardiogram performed the morning after placement of the coils showed residual leaks in 18%. At mean follow-up of 24.6 months repeat imaging showed residual leaks in only 3 of these patients (3%). We conclude that occlusion of small to medium-sized ducts using coils appears to be effective and is the treatment of choice. The use of a snare to hold and manipulate the coil as it is delivered improves control of the coil, the accuracy of its placement, as well as giving complete occlusion of the ducts.

Child↗

A national register for surveillance of inherited disorders: beta thalassaemia in the United Kingdom.

OBJECTIVE: To demonstrate the value of a national register for surveillance of services for an inherited disorder. METHODS: Data from the United Kingdom Thalassaemia Register and the United Kingdom Register of Prenatal Diagnosis for Haemoglobin Disorders were combined in a database; these registers include all fetuses known to have been diagnosed with beta thalassaemia major, beta thalassaemia intermedia, or haemoglobin E/beta thalassaemia in the United Kingdom. Data were extracted to show outcomes (selective abortion or live birth) of all fetuses and the status of those born with a disorder (alive, dead, successful bone marrow transplant, or lost to follow-up) by parents' region of residence and ethnicity. FINDINGS: At the end of 1999 the register included 1074 patients, 807 of whom were alive and residing in the United Kingdom. A successful bone marrow transplant has been performed for 117 out of 581 (20%) patients born since 1975. Residents of Pakistani origin are now the main group at risk in the United Kingdom, replacing residents of Cypriot origin. This has led to a marked shift in the need for services from the south-east of England to the Midlands and the north of England. Despite the acceptability of prenatal diagnosis, the proportion of affected births remains 50% higher than would be expected, reflecting a widespread failure to deliver timely screening and counselling to carriers. Even though effective treatment is available the annual number of deaths is rising, indicating that better tolerated treatments are needed. CONCLUSION: A national diagnosis register is a powerful instrument for monitoring the treatment and prevention of inherited disorders and for highlighting correctable shortcomings. In view of the increasing possibilities for genetic screening there is a strong case for central funding for such databases within modern health services.

Adolescent↗

Fluoroscopy guided retrograde ureteral stent insertion in patients with a ureteroileal urinary conduit: method and results.

PURPOSE: We evaluated retrograde double pigtail stent placement in patients with ureteroileal anastomosis. MATERIALS AND METHODS: Procedures were performed under digital C-arm fluoroscopic guidance and the patient under sedation analgesia. Radiography of the conduit was done to delineate urinary diversion anatomy and identify ureteral reflux. A purpose designed, angled tip catheter was used to direct a straight glide wire across the ureteroileal anastomosis. The glide wire was exchanged for a stiff guide wire for stent placement. We retrospectively evaluated the clinical records of 7 men and 5 women with a mean age of 54.3 years in a 7-year period. In 11 patients a new stent was placed because of ureteroileal stricture in 5, anastomotic leakage in 3, ureterolithiasis in 2 and recurrent malignancy in 1. RESULTS: New stent placement was successful in 10 of the 11 patients (90.9%, 13 of 16 ureters or 81.3%). Stent placement was successful in the 8 ureters in which reflux was noted on radiography of the conduit and in 5 of the 9 (55.6%) in which no reflux was noted. Stent replacement was accomplished in all 22 ureters (6 patients) in which it was attempted. Mean radiological screening time for new stent placement was 13.3 minutes (range 4.7 to 19.7), while for exchange it was 6.4 minutes (range 0.8 to 15.1). There were no immediate complications. CONCLUSIONS: This technique represents a useful approach to the ureter and should be considered an alternative to percutaneous nephrostomy and surgical revision. The approach is also useful for other ureteral procedures, including stone or migrated stent retrieval.

Adolescent↗

Coeliac disease--has the time come for routine mass screening? In 2002--2010--2020?

It might be clinically relevant to have a very low threshold when screening for coeliac disease. The question is how low? In countries familiar with coeliac disease, the classic pattern of severe malabsorption and cachexia, as described in textbooks, has become rare. Coeliac disease is not born in the minds of doctors diagnosing dyspepsia and/or irritable bowel syndrome, or associated auto-immune diseases, such as thyroid, diabetes mellitus type I, Sjögren's disease etc. The consequence is a delay in diagnosis, with secondary problems as long term autoimmune stimulation, osteoporosis and secondary malignancies. Enteropathy associated T-cell lymphomas are well known, but considering coeliac disease in T-cell lymphomas outside the gastrointestinal tract is not yet common sense. Large-scale screening studies on coeliac disease have been published and suggest a prevalence of coeliac disease in USA, Europe, Middle-East and Australia of about 1:200. Coeliac disease can be classified due to all these studies as an important health problem. However nation-wide screening programmes have not started yet, which are common for phenylketonuria and other metabolic defects. Probably they will be initiated as pilot-studies in national programmes within 10 years at the age of 2, and due to the bimodal distribution in CD with a later peak in the fourth decade, at 40 years. Additional data about cohorts of certain age groups are mandatory (f.i. 40 and/or 60 years), while initial discussions begin with national health authorities.

Celiac Disease↗

Limitations of the obstetric group B Streptococcus protocol.

OBJECTIVE: To assess compliance with the Centers for Disease Control and Prevention (CDC) screening-based protocol for obstetric group B Streptococcus (GBS) and to determine an acceptable threshold for protocol failure. STUDY DESIGN: A retrospective chart review was carried out for all deliveries performed through the resident-run community clinic from January through June 1999. Compliance with the CDC protocol was assessed by reviewing collected data from patient charts and comparing it to CDC requirements. Data were collected regarding patient demographics, antenatal GBS status, gestational age at screening, time of rupture of the membranes, time the antibiotic was given and time of delivery. RESULTS: A total of 248 charts were reviewed. Elective cesarean deliveries were excluded (25 charts). Unknown culture status was found for 22 (9.9%) patients. Cultures were collected before 35 weeks' gestation in 39 (17.5%) patients and at > 37 weeks' gestation in 28 (12.6%) patients. Of those with known positive GBS status, 4 (7.0%) were not treated, and antibiotics were given less than four hours before delivery in 13 (24.5%) patients. Of those with unknown status, six (27.2%) were not treated. Overall, there was 70% compliance with the culture collection arm of the protocol and 87% compliance with the treatment arm. CONCLUSION: Fulfillment of CDC guidelines in this community setting is imperfect. There are several areas beyond physician control, including precipitous delivery and patient non-compliance. However, perhaps an acceptable threshold for limitations of adherence to the protocol can be reached.

Adolescent↗

Vitamin B12 deficiency. Recognizing subtle symptoms in older adults.

Vitamin B12 deficiency is a common but under-recognized, yet easily treatable disorder in older adults. Although several causes exist, food-cobalamin malabsorption is now believed to be the most common etiology. Complications of vitamin B12 deficiency are myriad, ranging from lethargy and weight loss to dementia. Causes of deficiency include failure to separate vitamin B12 from food protein, inadequate ingestion, absorption, utilization, and storage as well as drug-food interactions leading to malabsorption and metabolic inactivation. The roles of B12 deficiency, elevated homocysteine and elevated methylmalonic acid in various disease states are still evolving. Timely screening and replacement of vitamin B12 will help prevent many complications.

Aged↗

Cervical cancer in India--strategy for control.

The available information on the incidence of cancers by site in India have indicated that of incidence of cancer of uterine cervix among women is by far the highest compared to other sites in women. The epidemiology of cervical cancer has been studied extensively in India and in other countries. The majority of factors related to cervical cancer are associated with sexual behaviour. The available evidence for control of cervical cancer is through secondary prevention, namely--early detection through Pap smear. In the present communication the alternative strategies with secondary prevention for control of cervical cancer is worked out. Taking into consideration the number of cervical cancer cases saved, number of woman years saved and the cost aspects the strategy at present for India should be to provide one life time screening for women at the age of 45 years.

Adult↗