Radiation doses from radiological imaging do not increase the risk of cancer

5 Reasons Why Scoliosis X-Rays Are Not Harmful

Radiographic imaging for scoliosis screening, diagnosis, treatment, and management is the gold standard assessment tool. Scoliosis patients receive many repeat radiographs, typically 10-25 and as many as 40-50, equating to a maximum 50 mGy of cumulative exposure. It is argued this amount of radiation exposure is not carcinogenic to scoliosis patients for 5 main reasons: 1. Estimated theoretical cumulative effective doses remain below the carcinogenic dose threshold; 2. Scoliosis patient x-rays are delivered in serial exposures and therefore, mitigate any potential cumulative effect; 3. Linear no-threshold cancer risk estimates from scoliosis patient cohorts are flawed due to faulty science; 4. Standardized incidence/mortality ratios demonstrating increased cancers from aged scoliosis cohorts are confounded by the effects of the disease entity itself making it impossible to claim cause and effect resulting from low-dose radiation exposures from spinal imaging; 5. Children are not more susceptible to radiation damage than adults. Radiophobia concerns from patients, parents, and doctors over repeat imaging for scoliosis treatment and management is not justified; it adds unnecessary anxiety to the patient (and their parents) and interferes with optimal medical management. X-rays taken in the evidence-based management of scoliosis should be taken without hesitation or concern about negligible radiation exposures.

Death of the ALARA Radiation Protection Principle as Used in the Medical Sector

ALARA is the acronym for "As Low As Reasonably Achievable." It is a radiation protection concept borne from the linear no-threshold (LNT) hypothesis. There are no valid data today supporting the use of LNT in the low-dose range, so dose as a surrogate for risk in radiological imaging is not appropriate, and therefore, the use of the ALARA concept is obsolete. Continued use of an outdated and erroneous principle unnecessarily constrains medical professionals attempting to deliver high-quality care to patients by leading to a reluctance by doctors to order images, a resistance from patients/parents to receive images, subquality images, repeated imaging, increased radiation exposures, the stifling of low-dose radiation research and treatment, and the propagation of radiophobia and continued endorsement of ALARA by regulatory bodies. All these factors result from the fear of radiogenic cancer, many years in the future, that will not occur. It has been established that the dose threshold for leukemia is higher than previously thought. A low-dose radiation exposure from medical imaging will likely upregulate the body's adaptive protection systems leading to the prevention of future cancers. The ALARA principle, as used as a radiation protection principle throughout medicine, is scientifically defunct and should be abandoned.

Patient Safety Analysis in Radiation Burden of Head Computed Tomography Imaging in 1185 Neurosurgical Inpatients

OBJECTIVE

We performed a retrospective analysis in a cohort of 1185 patients at our institution who were identified as undergoing ≥1 head computed tomography (CT) examinations during their inpatient stay on the neurosurgery service, to quantify the number, type, and associated radiation burden of head CT procedures performed by the neurosurgery service.

METHODS

CT procedure records and radiology reports were obtained via database search and directly validated against records retrieved from manual chart review. Next, dosimetry data from the head CT procedures were extracted via automated text mining of electronic radiology reports.

RESULTS

Among 4510 identified adult head CT procedures, 88% were standard head CT examinations. A total of 3.65 ± 3.60 head CT scans were performed during an average adult admission. The most common primary diagnoses were neoplasms, trauma, and other hemorrhage. The median cumulative effective dose per admission was 5.66 mSv (range, 1.06-84.5 mSv; mean, 8.56 ± 8.95 mSv). The median cumulative effective dose per patient was 6.4 mSv (range, 1.1-127 mSv; mean, 9.26 ± 10.0 mSv).

CONCLUSIONS

The median cumulative radiation burden from head CT imaging in our cohort equates approximately to a single chest CT scan, well within accepted limits for safe CT imaging in adults. Refined methods are needed to characterize the safety profile of the few pediatric patients identified in our study.

Whole-body computed tomography: a new point of view in a hospital check-up unit? Our experience in 6516 patients

BACKGROUND

There is a growing awareness that prevention and early diagnosis may reduce the high mortality associated with cancer, cardiovascular and other diseases. The role of whole-body computed tomography (WB-CT) in self-referred and asymptomatic patients has been debated.

AIM

To determine frequency and spectrum of WB-CT findings in average-risk subjects derived from a Medical-Check-Up-Unit, to evaluate recommendations reported and distribution according to sex and age-groups.

MATERIALS AND METHODS

We retrospectively reviewed 6516 subjects who underwent WB-CT (June 2004/February 2015). All were > 40 years and referred by Medical-Check-Up-Unit of our hospital. The main findings were categorized and classified as normal or not. Its distribution according to sex and age-groups was evaluated using Chi-square test and linear-by-linear association test, respectively. Number of recommendations, type and interval of follow-up were recorded. Descriptive statistics were used.

RESULTS

WB-CT performed in 6516 patients (69% men, 31% women, mean age = 58.4 years) revealed chest (81.4%), abdominal (93.06%) and spine (65.39%) abnormalities. Only 1.60% had completely normal exploration. Abnormal WB-CT in men was significantly higher than women (98.64% vs. 97.87%; p = 0.021), with significant increase as age was higher (40-49 years: 95.65%; 50-59 years: 98.33%; 60-69 years: 99.47%; > 69 years: 99.89%) (p < 0.001). Although most findings were benign, we detected 1.47% primary tumors (96, mainly 35 kidneys and 15 lungs). 17.39% of patients received at least one recommendation predominantly in chest (78.19%) and follow-up imaging (69.89%).

CONCLUSION

The most common WB-CT findings in asymptomatic subjects are benign. However, this examination allows identifying an important number of relevant and precocious findings that significantly increase with age, involving changes in lifestyle and precocious treatment.

AutoFoci, an automated high-throughput foci detection approach for analyzing low-dose DNA double-strand break repair

Double-strand breaks (DSBs) are the most lethal DNA damages induced by ionising radiation (IR) and their efficient repair is crucial to limit genomic instability. The cellular DSB response after low IR doses is of particular interest but its examination requires the analysis of high cell numbers. Here, we present an automated DSB quantification method based on the analysis of γH2AX and 53BP1 foci as markers for DSBs. We establish a combination of object properties, combined in the object evaluation parameter (OEP), which correlates with manual object classification. Strikingly, OEP histograms show a bi-modal distribution with two maxima and a minimum in between, which correlates with the manually determined transition between background signals and foci. We used algorithms to detect the minimum, thus separating foci from background signals and automatically assessing DSB levels. To demonstrate the validity of this method, we analyzed over 600.000 cells to verify results of previous studies showing that DSBs induced by low doses are less efficiently repaired compared with DSBs induced by higher doses. Thus, the automated foci counting method, called AutoFoci, provides a valuable tool for high-throughput image analysis of thousands of cells which will prove useful for many biological screening approaches.

Radiation Exposure of Premature Infants Beyond the Perinatal Period

OBJECTIVES

To determine the odds of premature compared with term infants exceeding the recommended radiation exposure threshold in the first year after discharge from birth hospitalization.

METHODS

In this observational retrospective cohort study, we compared the radiation exposure of premature and term infants between 2008 and 2015 in an urban hospital system. The primary outcome was crossing the radiation exposure threshold of 1 millisievert. We assessed prematurity's effect on this outcome with multivariable logistic regression.

RESULTS

In our study, 20 049 term and 2047 preterm infants met inclusion criteria. The population was approximately one-half female, predominantly multiracial or people of color (40% African American and 44% multiracial), and of low socioeconomic status. Premature infants had 2.25 times greater odds of crossing the threshold compared with term infants after adjustment for demographics (95% confidence interval [CI]: 1.66-3.05). Adjustment for complex chronic conditions, which are validated metrics of pediatric chronic illness, attenuated this association; however, premature infants still had 1.58 times greater odds of crossing the threshold (95% CI: 1.16-2.15). When the final model was analyzed by degree of prematurity, very preterm and extremely preterm infants were significantly more likely to cross the threshold (1.85 [95% CI: 1.03-3.32] and 2.53 [95% CI: 1.53-4.21], respectively), whereas late preterm infants were not (1.14 [95% CI: 0.73-1.78]).

CONCLUSIONS

Premature infants crossed the recommended radiation threshold more often than term infants in the year after discharge from birth hospitalization.

SHOULD WE BE CONCERNED ABOUT THE DOSES OF IONIZING RADIATION RELATED TO DIAGNOSTIC AND FOLLOW-UP IMAGING IN PATIENTS WITH SOLITARY PULMONARY NODULES?

Diagnosing solitary pulmonary nodules (SPNs) frequently requires radiological follow up associated with exposure to ionizing radiation. The aim of this study was to estimate the effective dose of ionizing radiation in patients diagnosed and followed up due to SPNs, which were found beyond lung cancer screening programs. We estimated the exposure to ionizing radiation as effective doses (ED) of all imaging techniques using ionizing radiation: chest computed tomography (CT), contrast enhanced CT (CECT) and positron emission tomography combined with CT (PET/CT) in each patient. The median ED related to CT, CECT and PET/CT were 27.8, 17.2 and 20.4 mSv, respectively. The total ED related to all imaging examinations performed during 2 years of radiological follow-up was 33.9 mSv (range: 3.2-122.4) per patient. Majority (59%) of radiation exposure resulted from repeated chest CT. In conclusion, diagnosis and follow up of patients with SPN with different radiological techniques is associated with high exposure to ionizing radiation.