A new American Journal of Neurology study found that radiologists performed 54% of lumbar puncture procedures (LPs) in 2017, representing significant growth over the 14-year longitudinal study. Lumbar punctures are a common procedure that can be performed by physicians in a variety of specialties. However, fluoroscopic guidance performed by a radiologist may be necessary in more complex cases. 

This study evaluated trends in performance of LPs by various medical specialties from 2003 to 2017 and raises the question of whether the shift of LPs from other specialties to radiology is justified. The results were also featured at the recent annual meeting of the Radiological Society of North America.

“As recently as 1991, only about 10% of lumbar punctures in the Medicare population were performed by radiologists, but the trend has not been studied since 2011,” notes lead author Derek Johnson, MD, nuclear radiologist and neuroradiologist at Mayo Clinic in Rochester, Minn. “In the present study, we show the continuing growth trend and use a detailed Medicare data set to identify disparities between specialties and provide insights into these trends.”

Johnson and his team used a nationally representative sample of Medicare enrollees, totaling approximately 2.5 million beneficiaries each year for the years 2004 through 2017, and mapped LP procedures to provider specialties.

The authors reported that the percentage of LPs performed by radiologists increased from 37% in 2004 to 54% in 2017 for a relative increase of 46%. Conversely, neurologist performed 24% LPs in 2004 and just 10% in 2017 for a relative decrease of 58%. Non-physician providers were the 4th most common provider group performing LPs in 2017 and had the largest relative increase over the study period, from 4% in 2004 to almost 8% in 2017.

The proportion of LPs performed by radiologists in each state showed geographic heterogeneity. The five largest states by population—California, Texas, Florida, New York, and Pennsylvania—all showed an increase in LPs performed by radiologists over the study period. In fact, radiologists were the most common provider of LPs by a large margin in both the inpatient and outpatient settings.

In the emergency department, however, emergency medicine physicians performed 80% of LPs each year. An analysis of patient complexity showed no difference between patients undergoing an LP by an emergency medicine physician or radiologist. Similarly, the trend of increased patient comorbidity over the study period was lower for radiologist versus non-radiologist LP cases. Collectively, the data do not support that the shift of LPs to radiology is driven by patient-level factors.

“The Medicare-age population is projected to grow from 56 million in 2020 to 94 million in 2060, and a proportionate increase in LPs can be anticipated,” says Richard Duszak, MD, FACR, professor and vice chair for health policy and practice in the department of radiology and imaging sciences at Emory University in Atlanta and senior affiliate research fellow at the Neiman Institute. “As demand for LPs thus increases, both radiology and non-radiology practices must prepare to fill this growing clinical void.”