Introduction
Various radiation reduction techniques researched to identify the most effective strategy for clinical utilization included kVp, mAs, Shielding, and Pitch. Each of these techniques was evaluated by determining the mean and standard deviations for different values obtained from different hospitals for different patients. Emphasis was laid on tests conducted on the head, C spine, chest, abdomen, and pelvis with the following results.
Head
The lowest mean value, 0.34, was registered with the kVp technique compared with other techniques. Each of the other techniques showed a mean value of 0.48 with the pitch technique indicating a slightly lower mean of 0.47. On the other hand, the P-value for all these techniques was the same, being greater than 0.10. The P-value indicates the probable extent to which variations between the techniques under study occurred. Measurements indicate the highest value of the standard deviation on mAs technique to be 0.12 while the rest of the techniques recorded lower values. According to the International Commission on Radiological Protection (19901, 150), the kVp figures do not show significant variation from recommended values.
Radiation doses can be varied using the kVp technique by selecting different voltages. However, radiographers should carefully select the applied voltage so as to minimize the risk of exposing the head to dangerous radiation. In addition to that, the quality of images generated through this technique should not be compromised by selecting voltage that is too low. The voltage value selected has to be settled on in accordance with an internationally accepted standard.
Spine
The highest mean value of 0.596 was recorded with the mAs technique while the lowest mean value of 0.5 was registered with the Pitch radiation reduction technique. The highest mean value was closely followed by the kVp value of 0.57. All these techniques were identified to be in 5 similar articles except shielding that was identified to be one only. On the other hand, the standard deviations for each technique vary significantly with mAs registering a standard deviation of 0.12 compared with kVp that registered a value of 0.10. Shielding recorded a standard deviation of 0.06 while Pitch recorded a standard deviation of zero.
All other techniques except Pitch registered a P-value greater than 0.1. On the other hand, mAs have the highest standard deviation indicating the quality dose reduction strategy to vary by ± 0.1, assuming a normal distribution. The quality of this radiation reduction strategy is closely followed by kVp and Shielding with no deviation for Pitch. Pitch, therefore, records values with no deviations from the actual mean, but remain constant. Assuming a normal distribution, Pitch values with zero standard deviation may register small radiation doses with no significant risk to the exposed patient. This technique could be most appropriate for the C spine.
Chest
The range of values registered on the chest with these exposures was highest on the Pitch strategy, being 0.545 and lowest on the kVp strategy, being 0.5243. On the other hand, the standard deviations of these values were highest with mAs strategy, being 0.0471 with the highest journal numbers (N) found to be 8 on the kVp technique. Journals for other techniques had similar values. All radiation reduction strategies registered fairly similar values implying, radiation reduction strategies were significantly the same for the chest. On the other hand, the lowest standard deviation in the chest is 0.05 with the mAs technique and the highest was o.13 with the KVp technique.
These figures suggest radiographers to pay careful attention to minimize exposures of radiation to the chest to avoid the risks associated with lengthy exposures. The standard deviations for mAs and Pitch vary slightly while kVp and Pitch register 0.13 and 0.12 respectively. Kubo, Lin, Stiller, akahashi, Kauczor, Ohno, and Hatabu (2007, 1) argue that reduction techniques should be selected that minimize high radiation risks to organs found in the chest.
Noise interferences should be minimized by increasing the current on the kVp technique. This could ensure high-quality images for clinicians and a one-time exposure for the patient in a radiation environment. However, dose values cannot be manipulated by varying the current but by selecting specific values to gain the best results, as argued by Moss and McLean (2006, 37) based on results from a variety of experiments.
Abdomen
Abdominal exposures registered a mean average of 0.5721 on mAs with the lowest value for kVp registering a value of 0.438. In the abdomen, the lowest kVp value has a standard deviation of 0.9757. The number of journals for the abdomen was highest at 7 on mAs and 5 on the kVp technique.
Pelvis
On the pelvis, the highest shielding mean value registered was 0.62 on the Shielding technique with the lowest value recorded being 0.26 on the mAs technique. On the other hand, mAs registered the lowest standard deviation of 0.0471 with sparingly registered P-values for all techniques. The scores for each number of articles were the same for each technique except for kVp that registered 2 articles. Elsewhere, observations by Frush, Donnelly, and Rosen (2003, 953) showed similar values, an affirmation that experimental values had not varied widely.
General results
All techniques register a P-value greater than 0.1 for all regions of exposure to the x-ray radiation except exposures on the Pelvis. Shielding and Pitch techniques record an overall mean percentage value higher than other techniques. On the other hand, kVp and mAs registered a significantly similar percentage of the mean distribution and the standard deviation. In addition to that, shielding and Pitch have a similar percentage mean and standard deviation. However, Karabulut and Ariyurek (2006, 5) argue that low doses may produce less quality work and high doses pose high risks for the patient. A value has to be determined that qualifies better results.
Limitations
Explored articles did not provide sufficient coverage of some techniques that were covered in the project limiting the diagnostic quality of the evaluated results. In addition to that, limited project time hampered further research on more techniques that employ different approaches and in different environments. Further still, lack of sources and adequate data for further analysis and evaluation limited the project scope. A number of journals provided average percentage data values of dose reductions while others provided non-specific information for the techniques being researched. In addition to that, findings from different hospitals on their dose reduction strategies were inadequately present to make informed decision.
Recommendations
Based on the limitations, the need for more time to conduct the research was recommended. That could allow the researchers to evaluate more data and articles, conduct other experiments with various variables with length time exposures and the effects of those exposures. Individualization of parameters involved in the scans, automatic exposures, and the effects of other variables such as image filters could also be factored in conducting further research. Students should be encouraged to conduct further research in critical fields. In addition to that, government support could vitally contribute to further research in this scientific field.
Conclusion
In this discussion, various techniques covered included kVp, mAs, Shielding, and Pitch with various mean values and standard deviations. In addition to that, various articles used in the project contributed to the study in evaluating and analyzing results from these techniques. Evidently, the number of tests should be increased since dose reductions should be urgently addressed. Appropriate use of the dose reduction strategies should be established and further research conducted with different patient sizes and different dose reductions to critically evaluate different dosages and the effect of exposure with time. In addition that, confounding factors and noise levels should be included in the analysis to help determine their effects on the quality of each radiation reduction technique.
References
Frush DP, Donnelly LF, Rosen NS.2003.
Pediatrics. Computed Tomography and Radiation Risks: What Pediatric Health Care Providers Should Know. Pediatrics Vol. 112 No. pp. 951-957. Web.
International Commission on Radiological Protection. 1991. Recommendations of the International Commission on Radiological Protection. ICRP publication no. 60. Oxford, UK: Pergamon, 1-201.
Karabulut N, Ariyurek M. Low dose CT: practices and strategies of radiologists in university hospitals. Diagn Interv Radiol 2006; 12:3 –8.
Moss M, McLean D. 2006.Paediatric and adult computed tomography practice and patient dose in Australia. Australas Radio 50:33 –40.
KuboT, Lin PP, Stiller WT, Akahashi M, Kauczor H-U, Ohno Y, and Hatabu H. 2007. Review. Radiation Dose Reduction in Chest CT: A Review. Web.