Quality initiative to reduce cardiac CT angiography radiation exposure in patients with congenital heart disease

Background: The use of cardiac computed tomography angiography (CCTA) as a complementary diagnostic modality to echocardiography in patients with congenital heart diseases (CHDs) is expanding in low- and middle-income countries. The adoption of As Low As Reasonably Achievable techniques is not widespread, resulting in significant unintended radiation exposure, especially in children. Simple quality improvement measures geared toward reducing radiation dose can have a impact on patient safety in resource-limited centers in low- and middle-income countries.Objectives: To determine how a quality improvement initiative can reduce radiation exposure during CCTA in patients with CHD.Methods: We designed a key driver -based quality initiative to reduce radiation dose during CCTA for CHD using protocol optimization, communication, and training and implementation as the drivers for intervention. Preintervention variables (radiation exposure, scanning protocols, and image quality) were collected from September 2012 to July 2016 and compared with variables in the postimplementation phase (February 2017 to July 2017). We compared quantitative and categorical variables using the chi-square test. Linear regression analysis was used to evaluate the effect of various factors on radiation dose.Results: We documented a reduction in the effective dose in the postintervention versus preintervention phase (mean, 2.0 versus 21 mSv, P \u3c 0.0001, respectively). Linear regression showed that the optimal organizational levels are associated with the same reduction in radiation. This finding shows that the time factor translates a combination of organizational and technical factors that contributed to the reduction in radiations.Conclusions: Our project showed a reduction in CCTA-associated radiation exposure

Moving back: The radiation dose received from lumbar spine quantitative fluoroscopy compared to lumbar spine radiographs with suggestions for dose reduction

Purpose: Quantitative fluoroscopy is an emerging technology for assessing continuous inter-vertebral motion in the lumbar spine, but information on radiation dose is not yet available. The purposes of this study were to compare the radiation dose from quantitative fluoroscopy of the lumbar spine with lumbar spine radiographs, and identify opportunities for dose reduction in quantitative fluoroscopy. Methods: Internationally reported dose area product (DAP) and effective dose data for lumbar spine radiographs were compared with the same for quantitative fluoroscopy and with data from a local hospital for functional radiographs (weight bearing AP, lateral, and/or flexion and extension) (n = 27). The effects of procedure time, age, weight, height and body mass index on the fluoroscopy dose were determined by multiple linear regression using SPSS v19 software (IBM Corp., Armonck, NY, USA). Results and conclusion: The effective dose (and therefore the estimated risk) for quantitative fluoroscopy is 0.561 mSv which is lower than in most published data for lumbar spine radiography.The dose area product (DAP) for sagittal (flexion + extension) quantitative fluoroscopy is 3.94 Gy cm2 which is lower than local data for two view (flexion and extension) functional radiographs (4.25 Gy cm2), and combined coronal and sagittal dose from quantitative fluoroscopy (6.13 Gy cm2) is lower than for four view functional radiography (7.34 Gy cm2).Conversely DAP for coronal and sagittal quantitative fluoroscopy combined (6.13 Gy cm2) is higher than that published for both lumbar AP or lateral radiographs, with the exception of Nordic countries combined data.Weight, procedure time and age were independently positively associated with total dose, and height (after adjusting for weight) was negatively associated, thus as height increased, the DAP decreased. © 2014 The College of Radiographers

Productivity of newly released maize varietiesby fertilizer application in Moshi Ruraldistrict, Kilimanjaro Region

A Dissertation 2019In Northern Tanzania, yield of maize ranges between 0.5 – 0.8 t ha -1 compared with the yield potential of 4–6 t ha -1 under research conditions resulting to yield gap of 5.2 t ha -1 . Major cause of low maize yield is low soil fertility due to insufficient use of fertilizers. A study was undertaken at Miwaleni (3o 25 ́ 30 ́ ́S and 37o 26 ́ 45 ́ ́ E) to determine the productivity of newly released maize varieties by fertilizer application in maize growing area of Moshi rural districtin Kilimanjaro region. Soils sampleswere collected from the experimental site. The objective of the study was to determine the response of maize yield on Nitrogen (Urea), Phosphorus (DAP, Minjingu Mazao, NPK cereal) fertilizers.The first experiment was conducted as split plot design in randomized completete block layout replicated three times. The factors were maize varieties (Situka MI, Meru HB 513 and Faru HB) while subplot factors were fertilizers types namely; DAP, at 62kg Pha -1 , Minjingu Mazaoat 71kg P ha -1 and NPK Cereal at 124kgP ha -1 . The second experiment was conducted as split split plot design in randomized completete blocklayout replicated three times. In the second experiment main and subfactor comprised four levels that were nitrogen ratesnamely; Nitrogen at 37.5, 50, 62.5 kg N ha -1 and no fertilizer application. Results obtained from the site, showed that the three phosphatic fertilizers applied, top dressed with respective nitrogen levels produced highly significant (P<0.001) grain yield over the control. Also Meru HB 513 and Faru HB produced highly significant (P<0.001) yield results than Situka M1 variety. Overal, the study results indicated that Minjingu Mazao and NPK fertilizers top dressed with nitrogen rates at 50kg Nha -1 and 62.5kg Nha -1 when applied on maize varieties (Meru HB 513, Faru HB) are the best strategies in improving maize grain yield in the study area

The Environment is Life

This participatory video titled 'The Environment is Life' was filmed and produced by a group of 11 members from Mwangoi and Malindi villages Lushoto District, Tanzania. With this video, they want to communicate the message 'people should conserve and protect the environment so that they live a good and healthy life'. Through the film they demonstrate how they protect the environment, improve their yields, and the systems they use. Through a 6 day process facilitated by Juliet Braslow (CIAT), Katherine Snyder (CIAT), Laibor Kalanga (CIAT), and Focus Muhogora (SARI), the farmers learned video techniques, interviewing skills, and developed the story they wanted to share with their community, local leaders, and the world

Initial quality performance results using a phantom to simulate chest computed radiography

The aim of this study was to develop a homemade phantom for quantitative quality control in chest computed radiography (CR). The phantom was constructed from copper, aluminium, and polymenthylmethacrylate (PMMA) plates as well as Styrofoam materials. Depending on combinations, the literature suggests that these materials can simulate the attenuation and scattering characteristics of lung, heart, and mediastinum. The lung, heart, and mediastinum regions were simulated by 10 mm x 10 mm x 0.5 mm, 10 mm x 10 mm x 0.5 mm and 10 mm x 10 mm x 1 mm copper plates, respectively. A test object of 100 mm x 100 mm and 0.2 mm thick copper was positioned to each region for CNR measurements. The phantom was exposed to x-rays generated by different tube potentials that covered settings in clinical use: 110-120 kVp (HVL=4.26-4.66 mm Al) at a source image distance (SID) of 180 cm. An approach similar to the recommended method in digital mammography was applied to determine the CNR values of phantom images produced by a Kodak CR 850A system with post-processing turned off. Subjective contrast-detail studies were also carried out by using images of Leeds TOR CDR test object acquired under similar exposure conditions as during CNR measurements. For clinical kVp conditions relevant to chest radiography, the CNR was highest over 90-100 kVp range. The CNR data correlated with the results of contrast detail observations. The values of clinical tube potentials at which CNR is the highest are regarded to be optimal kVp settings. The simplicity in phantom construction can offer easy implementation of related quality control program

Estimation of patient radiation doses from multi-detector computed tomography angiography procedures in Tanzania

The aim of the present study was to estimate the volume CT dose index (CTDIvol), dose length product (DLP) and effective dose (ED) to patients from five multi-detector computed tomography angiography (MDCTA) procedures: brain, carotid, coronary, entire aorta and lower limb from four medical institutions in Tanzania; to compare these doses to those reported in the literature, and to compare the data obtained with ICRP 103 and Monte Carlo software. The radiation doses for 217 patients were estimated using patient demographics, patient-related exposure parameters, the geometry of examination and CT-Expo V 2.4 Monte Carlo-based software. The median values of the CTDIvol, DLP and ED for MDCTA procedures of the brain and carotids were 36.8 mGy, 1481.0 mGy∙cm and 5.2 mSv, and 15.9 mGy, 1224.0 mGy∙cm and 7.8 mSv, respectively; while for the coronary, entire aortic, and lower limbs were 49.4 mGy, 1493.0 mGy∙cm and 30.6 mSv; 16.2 mGy, 2287.0 mGy∙cm and 41.1 mSv; and 6.4 mGy, 1406.0 mGy∙cm and 10.5 mSv, respectively. The ratio of the maximum to minimum ED values to individual patients across the four medical centers were 41.4, 11.1, 4.6, 9.5 and 37.4, respectively, for the brain, carotid, coronary, entire aortic and lower limb CT angiography procedures. The mean values of CTDIvol, DLP and ED in the present study were typically higher than the values reported from Kenya, Korea and Saudi Arabia. The 75th percentile values of the DLP were above the preliminary diagnostic references levels proposed by Kenya, Switzerland and Korea. The observed wide range of examination scanning protocols and patient doses for similar MDCTA procedures within and across hospitals; and the observed relatively high patient doses compared to those reported in the literature, call for the need to standardize scanning protocols and optimise patient dose from MDCTA procedures

Defining the diagnostic divide : an analysis of registered radiological equipment resources in a low-income African country

CITATION: Ngoya, P. S., Muhogora, W. E. & Pitcher, R. D. 2016. Defining the diagnostic divide : an analysis of registered radiological equipment resources in a low-income African country. The Pan African Medical Journal, 25:99, doi:10.11604/pamj.2016.25.99.9736.The original publication is available at http://www.panafrican-med-journal.comENGLISH SUMMARY : Introduction: Diagnostic radiology is recog nised as a key component of modern healthcare. However there is marked inequality in global access to imaging. Rural populations of low - and middle - income countries (LMICs) have the greatest need. Carefully coordinated healthcare planning is required to me et the ever increasing global demand for imaging and to ensure equitable access to services. However, meaningful planning req uires robust data. Currently, there are no comprehensive published data on radiological equipment resources in low - income countries . The aim of this study was to conduct the first detailed analysis of registered diagnostic radiology equipment resources in a low - income African country and compare findings with recently published South African data. Methods: The study was conducted in T anzania in September 2014, in collaboration with the Tanzanian Atomic Energy Commission (TAEC), which maintains a comprehensive database of the country’s registered diag nostic imaging equipment. All TAEC equipment data were quantified as units per million people by imaging modality, geographical zone and healthcare sector. Results: There are 5.7 general radiography units per million people in the public sector with a relatively homogeneous geographical di stribution. When compared with the South African publ ic sector, Tanzanian resources are 3 - , 21 - and 6 - times lower in general radiography, computed tomography and magnetic resonance imaging, respectively. Conclusion: The homogeneous Tanzanian distribution of basic public - sector radiological services reflects central government’s commitment to equitable distribution of essential resources. However, the 5.7 general radiography units per million people is lower than the 20 units per million people recommended by the World Health Organizati onhttp://www.panafrican-med-journal.com/content/article/25/99/full/Publisher's versio