An Investigation of Exposure to the Eyes and Thyroid of Personnel Near to Patient in Abdominal Radiography: A Phantom Study

Abdominal radiography is beneficial in a variety of clinical situations. Prior to the introduction of multiplanar imaging, it was considered as the main examination for gastrointestinal pathology. However, the radiation dose received is considered high since it is equivalent to the dose of at least 75 chest radiographs. Personnel including staff or relatives may be required to assist patients in many conditions, increasing unnecessary radiation and the likelihood of radiation-induced cancer. The purpose of this study was to determine the radiation dose received by personnel when eyes and thyroid are exposed during abdominal radiography. The Rando and body phantoms were used to represent personnel and patients in this experimental approach. The dose was measured as entrance surface dose (ESD) by using TLD-100, which was positioned at the Rando phantom's eyes and thyroid. The study included a total of twenty exposures, five times at each of four distinct sites. The mean doses (eyes/thyroid in mGy) were (0.083/0.081), (0.090/0.087), (0.093/0.092), and (0.092/0.089), respectively, at locations 1, 2, 3, and 4. The results indicated that there was no correlation between organ and location affecting ESD measurement (p=0.960). There was no significant difference in dose between the two organs (p=0.355), with the mean difference in the eyes being 0.002 more than in the thyroid. The proximity of the eyes to the tube source contributed for the increased dose observed at the eyes. Though ESD was substantial for location pairings 1 vs. 3 (p=0.001) and 1 vs. 4 (p=0.015) owing to the anode-cathode phenomena. In conclusion, personnel should avoid the tube source and cathode region, since they give a greater dose of radiation, particularly when the personnel are closest to the patient and does not have eyes or thyroid protection.

Minimising Radiation Dose in Computerised Tomography in the Investigation of Renal Stone Disease: A Teaching Hospital Audit

Background: CTKUB is a commonly performed scan as the gold standard investigation for renal stone disease. However, CT exposes a patient to ionising radiation. The radiation delivered to the patient increases in importance given the young demographic and often need for interval imaging. To minimise exposure, low dose scanning techniques are employed, and image field is reduced to only scan relevant anatomy. A common starting point for CT KUB is often the T10 vertebra however many scans are performed starting at higher levels exposing the patient to unnecessary radiation. Methods: A list of 100 patients who underwent CTKUB for renal stone disease at a teaching hospital was created. Following exclusion of duplicates and application of exclusion criteria 51 scans were included. Each scan was individually analysed to assess vertebral level of upper limit of kidney and vertebral level at which the CTKUB scan was started. Percentage overshoot was calculated as number of axial slices cranial to the upper aspect of the kidneys. Results: 22% of scans included in the study were started proximal to T10, these scans had a mean percentage overshoot of 19.6% exposing the patient to excess radiation. Of the CT KUB scans started at T10 or below mean percentage overshoot was improved to 8.6%. At the level of T10 all analysed scans would avoid undershooting. Conclusions: Implementation of a CTKUB imaging protocol which starts at T10 will minimise ionising radiation exposure whilst allowing visualisation of the complete renal tract. Keywords: CT KUB, Radiation safety, Minimise radiation

752 Routine In-Hospital Radiographs Following Anterior Cervical Discectomy and Fusion Surgery: Neither Necessary nor Cost-Effective?

Aim To evaluate whether a post-operative radiograph of the cervical spine before discharge is either clinically justified or cost-effective in patients who have undergone an ACDF, despite having satisfactory intra-operative imaging. Method A retrospective review of 101 ACDF patients from a single neurosurgical centre. 78 had an in-hospital post-operative radiograph, 23 did not. In 95 of these, it was documented that there was ‘satisfactory intra-operative imaging’. All patients had intra-operative imaging of completed instrumentation. Any post-operative complications were noted, and the length of hospital stay (LOS) recorded. Study parameters also included: levels operated on, whether or not a plate was used with a cage, additional costings to the hospital. Results There was one post-operative complication relating to the metalwork in the 101 patients. However, the decision to perform this x-ray was based purely on the deteriorating post-operative clinical picture. In the cohort that had POXR’s, the average length of stay was 66.7 hours. Without POXR, it was 21 hours. The additional cost to the trust of performing the in-hospital radiographs was calculated to be £71,523 per year. Conclusions In patients who undergo ACDF surgery with an uneventful post-operative course and satisfactory intra-operative imaging, in-hospital post-operative radiographs serve no clinical purpose and delay discharge. This gives additional cost to the trust, unnecessary radiation exposure and occupies potential bedspace.

The Bubble Eye Sign: Understanding the Radiological Imaging of Gas inside the Orbit

Gas, appears as radiolucent on X-ray, is normally absent in the orbit. However, intraocular surgeries occasionally utilize retained intraocular gas for tamponade effect. Intravitreal gas persists after retinal surgery, being confounded by the scleral shell of the operated eye, outlines the shape of the eyeball, and gives the characteristic bubble appearance on skull X-ray. This is different from orbital emphysema caused by orbital fracture when gas is located outside the globe but confined by the orbit, giving a crescent or concave shape over the superior orbit usually. Falls is common after intraocular retinal surgeries due to change of usual stereopsis, prolonged prone posturing, and other systemic comorbidities. By identifying the “Bubble Eye sign” described, attending physician should alert the presence of intravitreal gas, most commonly iatrogenic. Further ophthalmological history taking and examinations are thus indicated, instead of exposing patients to unnecessary radiation under computed tomography scan for orbital fracture investigation.

Using ultrasound for screening scoliosis to reduce unnecessary radiographic radiation – a prospective diagnostic accuracy study on 442 schoolchildren

Scoliosis screening is important for timely initiation of brace treatment to mitigate curve progression in skeletally immature children. Scoliosis screening programs frequently include the protocol of referring children screened positive with Scoliometer and Moiré Topography for confirmatory standard radiography. Despite being highly sensitive (88%) for detecting those who require specialist referral, the screening program was found to have more than 50% false positive rate that leads to unnecessary radiation exposure. Radiation-free ultrasound has been reported to be reliable for quantitative assessment of scoliosis curves. The aim of this prospective diagnostic accuracy study was to determine the accuracy of ultrasound in determining the referral status for children initially screened positive for scoliosis. 442 schoolchildren with a mean Cobb angle of 14.0 ± 6.6° were recruited. Using x-ray as the gold standard, the sensitivity and specificity of ultrasound in predicting the correct referral status were 92.3% and 51.6% respectively. ROC curve analysis revealed an area under curve of 0.735 for ultrasound alone and 0.832 for ultrasound plus scoliometer measurement. The finding provided strong evidences on the accuracy of ultrasound in determining the referral status that could result in more than 50% reduction of unnecessary radiation exposure for children undergoing scoliosis screening.

721 Imaging for Suspected Bowel Obstruction in Pennine Acute Trust (PAT): A Comparison with the National Audit of Small Bowel Obstruction’s (NASBO) recommendations

Background NASBO recommends Computed Topography (CT) over plain abdominal X-ray (AXR) for the investigation of bowel obstruction (BO). AXR is routinely used within PAT for investigation of BO which may be exposing patients to unnecessary radiation and adding unnecessary cost to the service. Method A retrospective audit collected data on patients with CT confirmed BO between July 2019 and February 2020. This looked at the percentage of patients who had both CT and AXR to investigate BO. The cost of these AXRs and the percentage of these AXRs that were normal were also calculated. Results A search identified 141 patients with CT proven BO. 81/141(57.4%) patients had both AXR and CT as a part of their initial investigations. Of those patients 26/81(32.1%) had no AXR features suggestive of BO. Only 12/81(14.8%) of those patients had serial AXRs following initial imaging. The cost for one AXR is £34.15 which means £2766.15 was spent on potentially unnecessary AXRs within this period. Conclusions PAT is performing potentially unnecessary AXRs which is exposing patients to unnecessary radiation and costing the trust. Plain AXRs do not rule out BO. We have recommended an investigation flowchart to PAT A&E departments to reduce unnecessary AXRs being performed.

Proton Therapy for Partial Breast Irradiation: Rationale and Considerations

In an era of continued advancements in personalized medicine for the treatment of breast cancer, select patients with early stage breast cancer may be uniquely poised to benefit from partial breast irradiation (PBI) delivered with proton therapy. PBI presents an opportunity to improve quality of life during treatment with a significantly shorter treatment duration. By targeting less non-target breast tissue, excess radiation exposure and resulting toxicities are also reduced. Proton therapy represents a precision radiotherapy technology that builds on these advantages by further limiting the normal tissue exposure to unnecessary radiation dose not only to uninvolved breast tissue but also the underlying thoracic organs including the heart and lungs. Herein, we present a concise review of the rationale for the use of proton therapy for PBI, evidence available to date, and practical considerations in the implementation and use of proton therapy for this indication.

Apical Cuts off as the Highest Prevalence of Errors during the Process of Periapical Radiograph Bisecting Technique by Dentistry Students

Background: Dental radiographs are a primary diagnostic tool that can be used for the benefit of treatment. Various errors during the process of periapical radiograph bisecting technique require repetition capturing, resulting in unnecessary radiation to patients, clinicians and radiologists. It also consumes a lot of time and is uneconomical. Purpose: To determine and analyze types, causes and prevalence of errors during the process of periapical radiograph bisecting techniques by students of Dentistry Faculty, Universitas Brawijaya. Method: This research is a descriptive analytic research with observational method on periapical radiograph bisecting techniques process which done in positioning, exposure, processing, and film handling steps. Samples selected by consecutive sampling method as many as 30 radiographs. Samples were observed by 3 observers whom noted errors that occurred in each radiograph. The data presented is based on the percentage of each error. Result: The results show errors in the positioning procedure are, crown cuts off 26.67%, apical cuts off 40%, cone cutting 3.33%, slanting of occlusal plane 30%, elongation 10%, foreshortening 16.67%, and overlapping 26.67 %; in exposure procedure there are no exposure 0% and double exposure 10%; in processing procedure there are overdeveloped 23.33% and underdeveloped 20%; and in film handling there is fingerprint contamination 6,67%. Conclusion: The most causative factors of errors is in the positioning procedure. The highest prevalence of error is apical cuts off, the lowest prevalence is no exposure.

Radical orchidectomy for suspected testicular cancer: Is preoperative staging computed tomography justified?

The standard of care for men with a suspected malignant testicular tumour and normal contralateral testis is radical orchidectomy, testicular tumour markers and computed tomography scan staging. If the definitive orchidectomy histopathology is benign, young men are potentially exposed to unnecessary radiation. We sought to establish the rate of benign pathology returned from radical orchidectomy at our local urology multidisciplinary team (MDT) and if there were any preoperative factors suggestive of benign lesions. We included patients discussed at our local MDT meeting regarding testicular tumours with histology following radical orchidectomy between 1 January 2016 and 31 December 2018. A total of 113 patients were included, with benign histology following radical orchidectomy in seven (6.2%) patients. The benign histology included one adenomatoid tumour, and the remainder showed features of either infarction or inflammation. Metastases were detected on staging imaging in 21% of patients. Of these, 64% had normal preoperative tumour markers. Neither tumour size nor number of preoperative ultrasounds correlated with a risk of benign histology. One patient had chemotherapy prior to orchidectomy. It was reassuring that just 6.2% of patients had benign histology with no significant factors predictive of benign histology. This supports pre-orchidectomy staging imaging and the current MDT pathway for suspected testicular cancers. Level of evidence: Level 2C.