RSNA2021 Redefining Radiology
Daily Bulletin

Short-Protocol MRI as a Cost-Effective Way of Detecting Minor Strokes

Wednesday, Dec. 01, 2021

By Nick Klenske

According to a recent European Radiology study, the use of short-protocol brain MRI on emergency patients with inconclusive neurological symptoms is a cost-effective method for detecting minor strokes. 

“Our results indicate that additional investment in short-protocol MRI examinations in the emergency settingnot only increases the detection rate of minor strokes but can also be regarded as a highly cost-effective strategy forpreventing major strokes,” said Daniel Puhr-Westerheide, MD, a radiologist at the University of Munich and the study’s lead author.

As Dr. Puhr-Westerheide explained during a pre-recorded presentation, this is because between 15% – 30% of all major strokes are preceded by minor strokes or transient ischemic attacks (TIA). Furthermore, nearly 40% of recurrent major strokes occur within seven days, and about 20% within 24 hours, after the initial minor stroke.

The Importance of Early Detection

Prior studies have demonstrated that the immediate use of secondary prophylactic treatment after a minor stroke can prevent 80% - 90% of subsequent major strokes. “This data clearly points to the pivotal role that the early detection of minor strokes can play in preventing a major stroke,” Dr. Puhr-Westerheide explained.

Although the most effective way to detect these minor strokes is with MRI, a lack of time and resources means this isn’t a very realistic option. “Performing a short, emergency MRI scan would be ideal for detecting small ischemic lesions and to increase diagnostic confidence in the emergency setting,” added Dr. Puhr-Westerheide.

Dr. Puhr-Westerheide further noted that the opposite is also true. “A negative MRI scan in the acute setting could support the diagnosis of stroke mimics and avoid unnecessary hospital admissions and secondary prophylaxis,” he said.    

A Cost-Effective Solution

In a previous study, short-protocol emergency MRI proved to be equivalent to standard-length protocol MRI in regard to image quality and lesion detection. The European Radiology study took this one step further, investigating the cost-effectiveness of using supplemental short-protocol brain MRI after negative non-contrast CT in neurological emergency patients with mild and nonspecific clinical symptoms.

The study found overall higher costs for patients without additional short-protocol MRI compared to patients undergoing additional MRI. More so, the cumulative calculated effectiveness in the CT-only group was lower compared to the additional short-protocol MRI group.

In the study’s deterministic sensitivity analysis, additional short-protocol MRI remained the dominant strategy in the ranges investigated. Even when assuming a relatively high cost for an ultrafast MRI of $500, it remained the most cost-effective strategy.

“Our study adds to the field as it demonstrates the cost effectiveness of supplemental short-protocol MRI subsequent to negative head CT in neurological emergency patients,” Dr. Puhr-Westerheide said.

Decreasing the Economic Burden of Major Stroke

According to Dr. Puhr-Westerheide, major stroke is of utmost clinical and economical importance, as it is associated with a very high economic burden for health care systems. For example, about 40% of all stroke patients suffer moderate to severe disabilities and need special care, and about 10% depend on long-term care facilities. More so, acute stroke care accounts for about one half of total direct medical costs within the first 12 months following ischemic stroke, with post-stroke care significantly contributing to the large expenses.

“The economic burden caused by ischemic stroke is tremendous,” Dr. Puhr-Westerheide said. “In 2008, the U.S. spent around $65.5 billion in stroke care — a figure that is expected to reach over $184 billion by 2030.”

Minor stroke patients, on the other hand, spend considerably less time in the hospital. Furthermore, fewer are admitted to the intensive care unit or are discharged to high-cost nursing facilities.

“In this context, our results indicate that additional investment in short-protocol MRI examinations in the emergency setting not only increases the detection rate of minor strokes, but can be regarded as a highly cost-effective, dominant strategy by preventing major strokes with consecutively high costs,” Dr. Puhr-Westerheide said.

Access the presentation, “Cost-Effectiveness of Emergency Short Protocol Brain MRI After Negative Head CT for Patients with Mild and Unspecific Neurologic Symptoms,” (SPR-NR-38) on demand at Meeting.RSNA.org.