It’s probably a good idea to do a repeat CT the morning of a scheduled bronchoscopy to make sure the pulmonary nodule is still there, according to investigators from Johns Hopkins University, Baltimore.

From Jan. 2015 to June 2016, 116 patients there were scheduled for navigational bronchoscopy to diagnose pulmonary lesions found on screening CTs. Eight (6.9%) – four men, four women, with an average age of 50 years – had a decrease in size or resolution of their lesion on confirmatory CT, leading to cancellations of their procedure. The number needed to screen to prevent one unnecessary procedure was 15. For canceled cases, the average time from screening CT to scheduled bronchoscopy was 53 days; for patients who underwent a bronchoscopy, it was 50 days ( Ann Am Thorac Soc. 2016 Dec;13[12]:2223-8 ).

It can take months to schedule a bronchoscopy after a pulmonary nodule is found on CT screening. Once in a while, the investigators and others have found, even suspicious nodules resolve on their own, and patients end up having a bronchoscopy they don’t need.

“If there is a significant delay from the initial imaging, practitioners should consider repeat studies before proceeding with the scheduled procedure … Same-day imaging may decrease unnecessary procedural risk … The optimal time that should be allowed to pass is difficult to ascertain,” said investigators led by Roy Semaan, MD, of the division of pulmonary and critical care medicine at Hopkins.

The team used a newer version of electromagnetic navigation bronchoscopy (Veran Medical Technologies, St. Louis), which requires expiratory and inspiratory CTs the morning of the procedure so software can build a virtual airway model to localize the nodule.

In addition to nodule resolution, same-day CTs might identify disease progression that alters the diagnostic plan of care.

“The most obvious risk associated with repeat CT imaging is the increased radiation exposure to the patient. Patients in our study who received inspiratory and expiratory CT scans … had a mean exposure of 9.485 mSv, which is not “negligible, but one-time doses at this range are generally considered to be low risk for contributing to the future development of a malignancy,” the team said.

The extra cost of a same-day noncontrast chest CT – about $300, the authors said – is more than offset if it cancels “an unnecessary procedure with its associated risks,” they said.

Dr. Semaan had no disclosures. Three investigators reported grants and personal fees from Veran.