With excitement of week nine on placement has made me to feel so confident to face the real radiography world. This week I have been working in Accident and Emergency department (A&E). I am happy with my ability in carrying out different radiographic examination, even though some of the A&E patient are quite challenging, to top it up I have been getting good comments from post qualified radiographer with regards to my adaptation of radiographic technique to suit patients physical/ psychological need .

During my time in A&E, I was opportune to observe one of the radiographer carrying out radiographic examination on a patient as a result of leg length measurements of the lower extremity.
Background reading from Golightly et al, (2007) defined leg length as a difference in lengths of the 2 legs. The study further highlighted that leg-length inequality may be caused by trauma, mild developmental abnormalities, onset in birth/childhood. It has been implicated as a cause of several conditions, such as trochanteric bursitis; knee pain; low back pain; osteoarthritis of the hip and knee; and running injuries, such as Achilles rupture etc.

In addition, the study also pointed out that different imaging modalities can be used to measure leg-length inequality, however radiography is the gold standard for measurement, other imaging modalities such as magnetic resonance imaging and computed tomography can be employed but they are expensive.

Slayton et al, (2012) in their study pointed out that other imaging technique can be employed for leg length examination as well using standard radiography include orthoroentogenogram, scanogram, and teleoroentgenogram. The only dilemma I have with this study is because the study was carried out in the U.S.A, so I believe their radiography practice is different from UK. However, the study made me to realise few limitations to all these techniques such as magnification error related to assessment of limb lengths, divergence of the x-ray beam etc.

The same study is also concerned about patient dose reduction in the utilisation of different radiographic technique. Due to recent advancement in technology, it came to light that microdose digital radiography is another form of computer- aided imaging that substantially reduces the radiation exposure to patients in comparison with conventional radiographic techniques. This technique works by using a vertical gantry, the patient stands in front of the x-ray assembly and remains stationary during the 20-second scanning process. According to the source, a patient receives an exposure of only 1 to 2 mrad during the scan; mrad is USA way of expressing x-ray exposure dose, looking at the dose recorded, it is well low dose compare to other radiographic techniques.

This examination was done on a normal computed radiography (CR) room, after processing the imaging cassettes, we realise that the image quality was too poor, with higher radiation dose recorded on the dose area product (DAP). As the superintendent he decided to re-examine the patient in the digital radiography (DR) room to ensure better image quality and to make sure diagnostic information are not missing. After the utilisation of digital scanning method for determining leg length. I evaluated the comparison on image quality, radiation dose on both systems.

By way of comparison, the DAP was ascertained from both systems. This measured value included the whole dose applied during the course of the examination. Collimation of the x-ray beam and tube filtration were taken into account.
Entrance dose recorded for this patient on a CR system for the whole leg length was 984 cGycm², with exposure of (90 kVp, and 60 mAs). And for the DR system entrance dose recorded for the same examination was 427 cGycm², with exposure of (120 kVp, and 60 mAs).This dose values shows that DR systems exhibits low radiation dose in comparison to a CR system.
A good image quality was produced using the DR rather than the CR system and that made it possible for the visualisation of correct area of interest such as the hip, knee and ankle joints, bony outlines was well defined, sharp trabecular pattern and adequate penetration with the exposure selected.

As part of my reflection during my academic session last year IDIS lecture on Radiobiology, I understand that Health Protection Agency, (2008) recommended patient dose information for different diagnostic examination. This highlights comparative radiation dose in the use of different radiographic technique. Please look at table below for more information.

DOSE TABLE

By doing this blog, I have been able to understand that different radiographic technique offers different radiation dose, due to maybe the body parts involve, i.e. Lumbar spine and abdomen requires a lot radiation in order to penetrate through the body tissues and acquire good images.

Kuhnley and Cueva, (2011) study pointed out that most of the increased exposure in the UK is due to CT scanning and nuclear imaging which require larger radiation doses than traditional x-rays. A chest x-ray, for example, delivers 0.02 mSv; while a chest CT delivers 8mSv see the table. This is 80 times as much. And that’s not counting the very common follow-up CT scans etc.

On the other hand, researchers such as Kuhnley and Cueva, (2011) estimated the potential risk of cancer from CT scans in 31,462 patients over 22 years. They highlighted that someone requires a CT or nuclear scan to treat or diagnose a medical condition; the benefits usually outweigh the risks. Still, if your clinician has ordered a CT, it’s reasonable to ask what difference the result will make in how individual condition is managed; for example, will it save an invasive procedure etc.

Also by doing this blog, I have utilised a wide range of different reference sources such as Health Protection Agency. This is well known independent UK organisation that was set up by the government in 2003 to protect the public from threats to their health from infectious diseases and environmental hazards. They provide advice and vital information to the general public to health professionals such as doctors and nurses, we the radiographers and to national and local government. Information gathered from them will serve as a guide in order ensure safe working environment and save life of individuals if we maintain the recommended radiation dose for different diagnostic procedure.

Other sources used such as Golightly, et al (2007) this source is not most recent, however it helped me to get a good background information about leg length and several conditions that can initiate discrepancy in leg length. Kuhnley and Cueva, (2011) source is most recent, it has helped me to rank different radiographic techniques in terms of the amount of radiation dose they can offer in comparison to traditional x-rays.

References:
Golightly, Y.M., Allen, K.D., Renner, J.B., Helmick, C.G., Salazar, A. and Jordan, J.M. (2007) Relationship of limb length inequality with radiographic knee and hip osteoarthritis. Osteoarthritis and Cartilage [online]. 15 (7), pp.824-829. [Accessed on 13 February 2013].

Health Protection Agency, (2013) Patient Dose information. Available From: http://www.hpa.org.uk/web/HPAweb&HPAwebStandard/HPAweb_C/119573382694 [Accessed on 09 March 2013].
Kuhnley, R. and Cueva, M. (2011) Learning About Cancer Has Brightened My Light: Cancer Education for Alaska Community Health Aides and Community Health Practitioners (CHA/Ps). Journal of Cancer Education [online]. 26 (3), pp.522-529. [Accessed on 13 February 2013].
Slayton, S., Williams, D.S. and Newman, G. (2012) Physical therapy services utilization and length of stay for obese patients following traumatic leg fracture. North Carolina Medical Journal [online]. 73 (1), pp.24-28. [Accessed on 13 February 2013].