Glowing Approach Helps Surgeons Assess Neural Blood Flow in Chronic Nerve Compression Neuropathy

In today's office environment, preventing the onset of carpal tunnel syndrome can be a daily challenge. In severe cases, surgery may be required to relieve nerve compression or repair damaged nerves. Aiding surgeons in visualizing areas where blood flow to nerves has decreased due to chronic compression could enhance diagnostic accuracy, improve severity assessments, and better predict outcomes.

A research team from Osaka Metropolitan University (Osaka, Japan) explored the use of fluorescein angiography, a technique commonly used in neurosurgery and ophthalmology to highlight blood vessels, to visualize neural blood flow in cases of chronic nerve compression neuropathies like carpal tunnel syndrome. The researchers found that fluorescein angiography effectively detected reduced neural blood flow in animal models (rats and rabbits) with chronic nerve compression, with results aligning closely with electrodiagnostic tests.

Image: Fluorescein-enhanced contrast imaging shows a rabbit’s normal sciatic nerve, left, and a damaged one (Photo courtesy of Osaka Metropolitan University)

The technique was then applied to human patients undergoing open carpal tunnel release surgery, where the findings also strongly correlated with electrodiagnostic results. Published in Neurology International, the findings suggest that fluorescein angiography may offer significant diagnostic value for assessing neural blood flow during surgical procedures.

“In surgery for severe chronic nerve compression neuropathy, the surgeon’s experience plays a big role in judging whether the surgical range is appropriate or whether additional treatment is necessary,” said Graduate School of Medicine student Kosuke Saito. “This research has shown that fluorescein angiography can visualize impaired areas and assess the impairment severity, so we believe that it has the potential to contribute to improving accuracy for related surgeries.”