Atlas Journal of Biology 2019, pp. 655–660 doi: 10.5147/ajb.v0i0.213 A tla s J ou rn al o f B io lo gy - IS SN 2 15 8- 91 51 . P ub lis he d B y A tla s P ub lis hi ng , L P (w w w. at la s- pu bl is hi ng .o rg ) Justification of Urgent Brain CT Examinations at Medium Size Hospital, Jerusalem Anan Al-Tell1, Majdal Hjouj2, Muntaser S. Ahmad3,*, and Hjouj Mohammad1,4 1 Radiology and Medical imaging department, Maqassed Hospital, Jerusalem, Palestine; 2 Medical School, Al-Quds University, Abu Deis - Main Campus, Jerusalem, Palestine; 3 Department of Medical Physics and Radiation Science, School of Physics, University Sains Malaysia, 11800 Penang, Malaysia; 4 Medical Imag- ing Department, Faculty of Health Professions, Al-Quds University, Jerusalem, Palestine. Received: October 25, 2019 / Accepted: December 8, 2019 __________________________________________________ * Corresponding author: altell.anan@gmail.com. 655 Abstract We studied requested urgent Brain CT Scan procedures justification. In addition, we addressed referrer’s (physi- cian’s) awareness of radiation risks. In doing so, we consid- ered two aspects to the issue. First, we reviewed the records of the requested urgent CT scan procedures for a sample of 339 patients at Al-Maqassed Hospital, a major hospital in Palestine. Secondly, we surveyed a sample of forty-two referrer’s from the same hospital to test their awareness of radiation risks. Our study shows that out of the 339 ur- gent brain CT requests, 69.6% were justified requests and 30.4% were unjustified. Statistically, these observations im- plied the following general statement: At least, 25% of the CT requests at this Hospital are unjustified with a p-value of 0.011. On the other hand, our survey on referrers shows that 42% of respondents knew the effective dose of a brain CT scan, 24% of respondents knew the radiation risks and 14% of respondents knew about radiation protection. Al- though the study is limited, yet it shows the need to reduce the number of brain CT examinations and the need to im- prove their justification. Consequently, the need for regu- lar education and guideline implementation at least in this country is of paramount importance. Keywords: Radiation risk, CT scan, Brain, Ionizing radiation. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://cre- ativecommons.org/licenses/by/3.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Introduction Diagnostic imaging modalities are increasingly applied in health care to diagnose the various injuries and diseases (Mer- zenich et al., 2012). In spite of the improvements of the medical imaging modalities in the quality of diagnosis and treatment in various medical conditions in both paediatric and adult patients, by using different medical imaging modalities that utilizes ion- izing radiation including conventional radiology, fluoroscopy, and Computed Tomography (CT). Scientific studies proved that radiation has biological effects on the organism and it depends on the dose and exposure duration (Squillaro et al., 2018). The CT has relatively high radiation doses compared with the other ionizing radiation modalities. Thus, the protection against the hazard of radiation is an important issue (IAEA,2009; Reme- dios, 2011). The principle of radiation protection related to the International Commission on Radiological Protection (ICRP) for ionizing radiation is justification, optimization of protection and application of dose limits (Agency, 2012). The justification process undergoes the base of risk versus benefit. This base is applied in various techniques, such as ion- izing or non-ionizing radiation (Malone et al., 2012). The justi- fication involves using all of the medical team including refer- ring physicians, radiographers, and radiologists (Malone et al., 2012). All examinations in diagnostic radiology shall then be justified to avoid unnecessary irradiation of patients (Remedios, 2011). The number of CT examinations is increasing every year (Brenner et al., 2007, Broder et al., 2006). Referring physicians at the emergency room (ER) who requested radiology examina- tions in a time-pressured environment need to know how di- A tla s J ou rn al o f B io lo gy - IS SN 2 15 8- 91 51 . P ub lis he d B y A tla s P ub lis hi ng , L P (w w w. at la s- pu bl is hi ng .o rg ) agnostic imaging is indicated as well as the necessity to know the accurate knowledge of the associated risks (Keijzers and Britton, 2010). By definition of justification, medical exposure is justified when the benefit of the examination is greater than the harm. Previous investigations show that hundreds of examinations requested every year are not justified and most of them are not necessary at all; including the CT examinations((Malone et al., 2012; Teferi et al., 201 ; Hobbs et al.,2018; Vassileva et al., 2012). Also, some of these studies show that there is a preva- lent disregard of radiation doses among physicians (Wong et al., 2012; Thomas et al., 2006; Rice et al.,2007; Heyer et al., 2010). With the increase of radiation exposure towards patients, re- ferring physicians play a greater role in the proper choice of investigation as well as deciding the right choice for the patient. There are some studies that have been conducted on the knowl- edge about radiation protection for health professionals who work with ionizing radiation (Muhogora et al., 2010). However, they are a few studies that have been applied to the reference of a physician’s knowledge regarding the justification of the pro- cedures (Moifo et al., 2018). The goal of this study is to determine whether previous CT examinations done at Makassed Hospital in Jerusalem on the patients who entered the emergency department were justified. To accomplish this, patient files of 339 urgent brain CT exami- nations were retrospectively reviewed. Also, a questionnaire made up of 42 physicians was created to analyse the referring physician’s awareness of radiation risks and weather the re- quests of medical imaging procedures can be justified or not. Materials and Methods A Sample of Patients Participants chosen for the study were patients who urgently referred from the ER for 6 months from the first of January to the 30th of June 2018. Approximately 339 patients with suspected or confirmed head injury with or without other major trauma were studied. The study referred to the archive of the hospital through the hospital information system (HIS) which records all observations before examinations are done. Then, the results of those examinations are written and then compared. An institutional review approval was obtained for this pro- spective study. The patient consent was conceded, but the pa- tient particularity was conserved by using the patient ID with- out mentioning the name of the patient. Emergency department patients were included, other departments were excluded. Also, emergency department patients who during the morning work- ing shift 7:00 AM to 3:00PM as elective and scheduled were excluded while patients between 3:00 pm to 7:00 am were in- cluded. The data collection method included reviewing patient notes during emergency situations. We used the HIS archive which is used in the hospital. The data for each patient included age, gender, clinical data (obtained from the ER physician), the exam indications and the findings written by radiologists. The 656 patients who have no written finding reports were also exclud- ed. A Sample of Doctors Fourty two (42) referring physicians from the hospital be- lieve that they can justify at least ten brain CT requests of im- age procedures per week. Thus, a plan has been developed to interview each potential respondent in the hospital. Each meet- ing session concluded explanations that were provided from the respondent according to the objectives of the survey, the confi- dentiality of the responses and the anonymous nature of the sur- vey model. Once approved, the pre-screened questionnaire is administered to the respondent. Sampling was continuous and easy going. Radiologists and radiographers were excluded. The questionnaire consisted of a section on the person interviewed (gender, qualification, years of experience), a section on knowl- edge and the exercise of justification for the examination of the required medical radiation with emphasis on the effective dose of brain CT scans and radiation risks. Other questions focused on the responsibility of justification and the daily practice of referring physicians on the justification of the required exami- nations and the principles of radiation protection. The main part of the questionnaire is shown in Appendix 1. Data Analysis Two experts in radiology with the new south Wales Minis- try of Health NSW Health clinical practice guideline (Haydon, 2013) wrote the following findings for each exam. It also as- sessed the justification of the performed examinations based on the referrals. The analyses of examinations were divided into two groups; justified and unjustified, and the percentage of the two groups were calculated. The guideline requirements for indicating the potentially significant mild head injury summa- rized in Table 1. This scale can be applied with the time it took to deal with the patients. However, because our work is on the retrospective study; this scale cannot be applied. Thus, researchers put a scale A tla s J ou rn al o f B io lo gy - IS SN 2 15 8- 91 51 . P ub lis he d B y A tla s P ub lis hi ng , L P (w w w. at la s- pu bl is hi ng .o rg ) Table 1. Initial management of adult closed head injury (NSW Health algorithm). A-WPTAS, Abbreviated Westmead PTA Scale; GCS, Glasgow Coma Scale. 1 GCS < 15 at 2 h after injury. 2 Deterioration in GCS 3 Focal neurological deficit 4 Clinical suspicion of skull fracture 5 Vomiting (especially if recurrent) 6 Known coagulopathy or bleeding disorder 7 Age >65 years 8 Post-traumatic seizure 9 Prolonged loss of consciousness (>5 min) 10 Persistent post-traumatic amnesia (A-WPTAS <18/18 at 4 h after injury 11 Persistent abnormal alertness/behavior/cognition 12 Persistent severe headache 13 Large scalp hematoma or laceration 14 Multi-system trauma 15 Dangerous mechanism 16 Known neurosurgery/neurological impairment 17 Delayed presentation or representation 657 A tla s J ou rn al o f B io lo gy - IS SN 2 15 8- 91 51 . P ub lis he d B y A tla s P ub lis hi ng , L P (w w w. at la s- pu bl is hi ng .o rg ) that consists of four groups from 1 to 4 as follows: Group 1 (G1): Brain CT examination of cases related to head trauma and its involvement with road traffic accidents (RTA), motor vehicle accidents (MVA) and falling down cases. Group 2 (G2): Brain CT examinations of patients with vom- iting, dizziness, seizure, and convulsion. Group 3 (G3): Brain CT examinations of patients suffer- ing loss of consciousness, sleepiness, side body weakness, numbness, and severe headache. Group 4 (G4): Brain CT examinations after surgery (post- operative). The statistical analysis was obtained using the Statistical Package for Social Sciences. Results As we mentioned, a total of 339 urgent brain CT request forms were received during the study period (6 months). Of these; 209 (61.65%) were males and 130 (38.35%) were fe- males. 111 (32.74%) were children less than 16 years, 228 (67.26%) were over 16. Out of the total 339 CT request forms, 105 (30.98%) received were for patients in the ER who stayed in different departments inside the hospital, while 234 (69.02%) brain CT requests were for patients who were at the ER and who stayed under observation for 24 hours and were then discharged the next day. Out of the 22 patients who were excluded from the study; 10 of them were not given a report due to their impatience. The remaining patients did not have an examination request. Table 2 and Figure 1 provide summary of the distribution of age, gender, and patients who were included as well as those were excluded in the study. As it is a retrospective study, it is difficult to justify every request based on clinical data only. In our study, we consider the exam retrospectively justified, if the note demonstrate that the patient belongs to one of the four group. Table 3 and fig- ure 2 show the distribution of the justified and non-justified re- quests. The study estimates that 236 (69.6%) requests of the total 339 was retrospectively considered a justified request, as the request fall in one of the four group, while 103 (30.4%) was not fulfilling the justification criteria applied to our study. Statistically: The sample size is n=339, the number of un- justified requests is 103. Let P denotes the proportion of the unjustified requests at this Hospital in general, and Pv denotes the proportion of the unjustified requests in our sample study. Then, from the test Ho: P ≤0.25 and Ha: P>0.25, we have the following: a 95% confidence interval for P is 0.255 < P < 0.353 , and a p-val- ue=0.011 as shown in Figure 3. This strongly support the con- clusion that P> 25% (Figure 3). Our two experts wrote the difference between the clinical data (indication) with the data findings (reports). Out of the 339 patients, 23 (6.78%) had no radiology report, while 104 (30.67%) had normal results after the brain CT examination. This study estimates that 26 patients (7.66%) had mismatch- es between the indications and the correct findings after the ex- aminations were done. Keeping in mind, a brain CT indication is not a hard requirement to achieve from ER physicians. 129 (38.05%) out of the 339 patients had matchings between the final reports with the clinical data, while 57 (16.81%) patients had mismatches between the final reports and exam indications. However, it’s still important to request brain exams from ER physicians because the reports do show emergency findings in- side these cases. In essence, to check the accuracy for brain CT examination requests from ER physicians, while excluding radiologist re- Demographics January February March April May June Total Male split 26 28 26 42 40 47 209 Female split 15 13 23 28 29 22 130 Children patients <16 8 7 10 38 25 23 111 another patient >16 33 34 39 32 44 46 228 Patients included 36 40 49 67 64 61 317 Patients Excluded 5 1 0 3 5 8 22 Inpatient 15 12 23 22 15 18 105 Outpatient 26 29 26 48 54 51 234 Table 2. Demographics of clinical study cohort. Month J N.J %J %N.J T 𝑮𝟏 𝑮𝟐 𝑮𝟑 𝑮𝟒 January 41 5 11 2 6 17 58.53 41.46 February 41 9 3 14 3 12 70.74 29.26 March 49 10 3 15 10 11 77.56 22.44 April 70 22 6 15 7 20 71.43 28.57 May 69 23 4 6 10 26 62.32 37.68 June 69 29 9 8 6 17 75.37 24.63 Total 339 98 36 60 42 103 69.6 30.4 Table 3. Documentation for justified and non-justified requests. A tla s J ou rn al o f B io lo gy - IS SN 2 15 8- 91 51 . P ub lis he d B y A tla s P ub lis hi ng , L P (w w w. at la s- pu bl is hi ng .o rg ) 658 A tla s J ou rn al o f B io lo gy - IS SN 2 15 8- 91 51 . P ub lis he d B y A tla s P ub lis hi ng , L P (w w w. at la s- pu bl is hi ng .o rg ) ports, we distributed three categories of findings: a. True-negative: acts for the patients, who had a request to do an examination with a result. This category consists of both pa- tients with matchings between the examination indication and the final report and those patients who have a mismatching be- tween the clinical data with the radiology report. According to the reports, it was estimated that 54.86% show an importance for the exam to be made. b. True-positive: refers to the patients, an estimation of 30.67% who had a request to do the examination with normal results. c. The third category: consists of patients who had a request to do the examination, but the examination did not undergo the emergency exam, with an estimated 7.66%. From these results, we come to know that the accuracy of ER doctors only reached 54.86%. Table 4 summarized these results. There were 130 patients (38.34%) that received a brain CT without having the documented criteria required to justify the investigation based on the NSW Health program. According to the questionnaire on doctors, the results for each question are shown in Table 5. According to this survey, 18 referrers (42%) of the 42 ques- tioned referrers know the effective dose of the brain CT scan. However, just 13 referrers (3%) has known that the effective dose of one brain CT scan is equal to the effective dose of 100 chest x-ray (a routine emergency radiological exam). In despite the that all referrers believe ionizing radiation is a risk factor for cancer development, only 24% of the them have known the exact excess risk of cancer from radiation. Six referrers (14%) of all respondents knew the basic prin- ciples of radiation protection, and 10 referrers (23%) consider a local or an international protocol when request an urgent brain CT scans. Discussion In this current study, the requests for brain CT examinations over a six month period are reviewed. Approximately 30.4% was not justified, the degree of justification was only about 69.6%. Our present study shows that the un-justification of brain CT examinations was statistically significant. For the chil- dren, the un-justification exams are at a significant high, with the total number of examinations for children being less than adult patients. This result is similar to a previous study done in Germany (Merzenich et al., 2012). The number of brain CTs carried out on adult patients increased significantly, which were ordered after 15:00 o’clock comparing with the time before. No Report Normal Report Matching Report with Clinical Data Mismatching T F January 3 8 18 10 2 February 1 10 14 7 9 March 4 11 25 8 1 April 3 26 23 12 6 May 5 19 26 15 4 June 7 30 23 5 4 Total 23 104 129 57 26 Questions Correct Answer Correct Answer Percent Q1 C 42% Q2 C 3% Q3 D 24% Q4 D 14% Q5 A 23% Table 4. The accuracy of ED physicians for order the brain CT exams. Table 5. The questionnaire results. Figure 2. Distribution of the justified and non-justified re- quests during the period of study. Figure 3. Test on the proportion of the unjustified requests. Figure 1. Distribution of age, gender, and patients who were included as well as those were excluded in the study. A tla s J ou rn al o f B io lo gy - IS SN 2 15 8- 91 51 . P ub lis he d B y A tla s P ub lis hi ng , L P (w w w. at la s- pu bl is hi ng .o rg ) 659 Despite the recommendations, radiologists were not regularly consulted before brain CT’s were requested for adult patients. The analysis of justification for a brain CT is also challenging because of the multiple and variable indications. According to the questionnaire on a sample of referring physicians, the level of knowledge of referring physicians re- garding justification for the request of radiating examinations was not satisfactory. This is harmonious with many previous studies: o’Sullivan et al which shows that 87% of the study population and 89% of controls considered that they had nev- er been exposed to lectures or teaching focussed on radiation protection; Soye and Paterson which demonstrated that Fifty- four percent of students reported a moderate confidence in their knowledge about radiation and risks. Borgen et.al study shows that the mean radiation knowledge score was 30.4/71. Most re- spondents underestimated doses from high-dose imaging, e.g., barium enema (94.7%), chest CT (57.7%) and abdominal CT (52.7%). Limited radiation knowledge was not compensated by using guidelines. Only 20% of physicians and 72% of non-phy- sicians used referral guidelines and the Krille.et al systemic review which showed moderate to low knowledge among phy- sicians concerning radiation doses and the involved health risks (O’Sullivan, 2010; Soye and Paterson, 2000; Zewdneh et al., 2012; Borgen, 2010; Krille,2010). This level of knowledge has not changed with professional experience or qualifications. The explanation might be the lack of initial training during medical studies and the absence of regular structured education in Hos- pitals on radiation protection. There are several limitations to this study. The major limita- tion is that this study contains information from one institution only. The patient number selected for the justification evalua- tion is also low. The study dealt with brain CT examinations only. The data collection required to deal with the patients at the time of an examination to determine which patients fitted the criteria. Also, the study concerned the ER and not all hospital departments and it only focused on the patients after the 15:00 o’clock. In general, it is probably impossible to reach 100% justifica- tion. However, it is still essential to develop a justification pro- cess. Regular updating of referral guidelines with the computer system used at the hospital to increase justification. Continuous and easy communication system between referrers, radiogra- phers and radiologists will improve the unjustifiable exam by feedback for each request. PACKs and HIS system make these communications easier and smooth. In conclusion, the study has shown that it is possible to re- duce the number of brain CT examinations and to improve their justification by regular education, guideline implementation and to educate physicians about the ionizing radiations related to medical imaging, given their legal responsibility as dispens- ers under the ionizing radiation regulations (medical exposure) in the hospital. 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Q2: if we consider the chest x-ray effective dose as 1 unit, the effective dose of the brain CT scan will be 1. 10. 100. 1000 10000 Q3: the excess risk of cancer from radiation is 1/10000 mSv. 1/100000 mSv. 1/100 mSv. 1/4000 mSV. No increase in cancer risk. Q4: The radiation protection philosophy that promotes the use of the least amount of radiation possible for medical imaging is termed: NCRP NRC ICRP ALARA Q5: When you order a brain CT scan especially in trauma patients, do you consider any local or international guidelines. Yes. No.