Advances in diagnostic imaging technology have meant that more trauma patients are being diagnosed with blunt cerebrovascular injuries, and as a result, stroke and related death rates in these patients have declined significantly over the past 30 years. These changes are due to the evolution of imaging technology, namely CT scanning, and its wide availability in hospitals, according to a new study from the University of Tennessee Health Science Center (UTHSC).
The researchers found that the percentage of blunt trauma patients diagnosed with blunt cerebrovascular injury (BCVI), a type of severe injury to main vessels that supply blood to the brain, increased six-fold: from 0.33 percent to 2 percent from the beginning of the study period in 1985 to the end in 2015. However, the percentage of these patients who went on to have a stroke due to these injuries declined from 37 percent to 5 percent over the same period, and those who died from BCVI declined from 24 percent to zero in that time. The researchers evaluated 564 patients diagnosed with BCVI from hospital records and the trauma registry at the Elvis Presley Regional Trauma Center.
"This study shows the importance of the reevaluation and reassessment of how physicians and trauma teams take care of specific injuries, in this case blunt cerebrovascular injury, because changes in technology and awareness of this injury and its management, diagnosis, and treatment have evolved over the years," according to lead study author Louis J. Magnotti, MD, FACS, associate professor in the UTHSC department of surgery.
The researchers evaluated results in three separate 10-year eras over which the average age of trauma victims increased from 34 to 43 years. The overall group with BCVI was predominantly male (65 percent) with an average age of 41 years and an average injury severity score (ISS) of 27 (major trauma is defined as an ISS of 15 or greater). However, the study noted that males made up 68 percent of all blunt trauma patients over the 30-year period, indicating that female blunt trauma victims may be predisposed to BCVI. Females were also significantly more likely to be victims of a motor vehicle accident, the most common cause of BCVI, the authors stated.
The researchers noted that before 1990, fewer than 100 cases of BCVI had been reported in the medical literature. Over the last 30 years, however, the study identified three trends that have led to an increase in its diagnosis: the emergence of regional trauma centers; advances in imaging first with digital subtraction angiography and more recently computed tomographic angiography (CTA); and greater awareness of the risk of stroke with vertebral artery injuries and the screening methods that focus on these injuries.
The researchers explained that angiography involves injection of a contrast dye that appears highlighted under radiographic imaging to show tears, ruptures, and blockages in the blood vessels. Digital subtraction angiography is more invasive than CTA, which can be done under many widely available CT scanners.
"Clearly the advances in CT-scanning technology that developed since the first CT scanners came out to being able to do CT angiography – which is really a noninvasive form of angiography – have significantly improved diagnosis," Dr. Magnotti said, noting that conventional angiography is still the "gold standard" for diagnosis of BCVI, but that newer generations of CT scanners may in time replace the older technology.