Pre-Employment Screening Chest X Rays Can Safely Omit Lateral View
NEW YORK, April 30, 2009 — In an occupational health setting, a single posteroanterior (PA) chest X ray is sufficient for tuberculosis screening, according to a presentation at the American Roentgen Ray Society 2009 Annual Meeting in Boston.
"In the study we did, screening more than 800 asymptomatic individuals with positive purified protein derivative (PPD) results, every abnormality was seen on the frontal view; most abnormalities were not seen on the lateral view; and the lateral view did not add any information," Dr Ronald Eisenberg told Reuters Health after his presentation.
In addition, obtaining only the PA view reduces radiation exposure to the patient by approximately 67%, he said. "So in this setting, the conclusion is that the lateral view can be eliminated.
"Guidelines from the American Thoracic Society and the CDC [Centers for Disease Control and Prevention] say that people with positive PPD results should have a frontal chest film and whatever additional views are considered appropriate," Dr Eisenberg continued. "The problem is, in most radiology departments, stopping to determine if a lateral view is necessary interrupts the work flow, so most technologists routinely do both."
To see if the lateral projection adds clinically relevant information to the PA view, Dr Eisenberg et al reviewed radiographs from 875 adults screened in 2007 at Beth Israel Medical Center's employee health service in Boston. Ninety-one individuals had radiographic abnormalities, including calcified lymph node or granuloma, apical pleural thickening, noncalcified nodule(s), and fibrous scarring.
The lateral view did not change the interpretation made on the PA view alone, the researchers found. But, Dr Eisenberg emphasized, "These were people with no symptoms. The situation is entirely different for patients positive for PPD and with chills, night sweats, or other symptoms—in such cases, both radiographs should be obtained."
Also, for most clinical indications, such as pneumonia or suspected lung cancer, more than 1 view is absolutely necessary, he added.
Still, he believes that for most screening purposes, such as at hospital admission or prison intake, obtaining a single PA view is likely to be sufficient.
Source: Reuters Health Information
