A 3-D model built from previous CT scans helped French surgeons avoid damage to a nerve that ran along an abnormal path in a patient's neck as they removed a tumor, they explain in a letter to The New England Journal of Medicine.
The 66-year-old woman underwent surgery to remove a tumor from her parathyroid gland. Previous CT scans, however, showed the unusual route of her laryngeal nerve, a divergent path that occurs in only 1 percent of patients, HealthDay explains. Damage to the nerve can leave hoarseness and voice loss.
Before surgery, a team of endocrine surgeons, radiologists, and a computer scientist adept at medical-imaging software built the model, which showed the location of her blood vessels and nerves. They say the virtual images also can be overlaid on the actual images taken during surgery to provide a better understanding of the nerves and blood vessels in the area.
Johns Hopkins researchers have used a similar overlay technique using augmented reality and magnetic resonance imaging to accurately guide a needle for joint arthrography.
One expert told HealthDay, however, that the condition occurs so rarely that it calls into question the clinical value of the software. Bruce Davidson, a professor of otolaryngology-head and neck surgery at Georgetown University Hospital in Washington, D.C., said he's seen the condition only three times out of a thousand thyroidectomies and recognized it each time.
In addition to exposing patients to radiation, CT scans have been linked to rare complications called thyroid storm in people with a hyperactive thyroid gland that leads to high blood pressure and agitation, HealthDay says.
The authors are working to adapt the software using MRI to eliminate those risks, though that would be more costly. It already can use ultrasound, though it is less precise than MRI.
In addition to the work at the Research Institute against Digestive Cancer in Strasbourg on 3-D imaging in connection with parathyroid surgery, the researchers have used the software to guide surgeons in removing a cancerous adrenal gland and in surgeries of the liver and pancreas.
As the use of 3-D modeling grows in medicine, it's one factor in the hot growth of mobile applications. With the mHealth global market expected to hit $11.8 billion by 2018, sophisticated apps for medical professionals, such as those providing access to patient information or to create 3-D anatomical models, make up 30 percent of the total.
To learn more:
- read the letter
- here's the HealthDay article