"... Scans — more sensitive and easily available than ever — are increasingly finding abnormalities that may not be the cause of the problem for which they are blamed. It’s an issue particularly for the millions of people who go to doctors’ offices in pain.
The scans are expensive — Medicare and its beneficiaries pay about $750 to $950 for an M.R.I. scan of a knee or back, for example. Many doctors own their own scanners, which can provide an incentive to offer scans to their patients.
And so, in what is often an irresistible feedback loop, patients who are in pain often demand scans hoping to find out what is wrong, doctors are tempted to offer scans to those patients, and then, once a scan is done, it is common for doctors and patients to assume that any abnormalities found are the reason for the pain.
But in many cases it is just not known whether what is seen on a scan is the cause of the pain. The problem is that all too often, no one knows what is normal.
... Why do a scan in the first place? There are some who may benefit from surgery, but does it make sense to routinely do scans for nearly everyone with back pain? After all, one-third of herniated disks disappear on their own in six weeks, and two-thirds in six months.And surgeons use symptoms and a physical examination to identify patients who would be helped by operations. What extra medical help does a scan provide? So Dr. Modic did another study, this time with 250 patients. All had M.R.I. scans when they first arrived complaining of back pain or shooting pains down their leg, which can be caused by a herniated disc pressing on a nerve in the spine. And all had scans again six weeks later. Sixty percent had herniated disks, the scans showed.
Dr. Modic gave the results to only half of the patients and their doctors — the others had no idea what the M.R.I.’s revealed. Dr. Modic knew, though.
In 13 percent of the patients, the second scan showed that the herniated disk had become bigger or a new herniated disk had appeared. In 15 percent, the herniated disk had disappeared. But there was no relationship between the scan findings at six weeks and patients’ symptoms. Some continued to complain of pain even though their herniated disk had disappeared; others said they felt better even though their herniation had grown bigger.
The question, though, was whether it helped the patients and their doctors to know what the M.R.I.’s had found. And the answer, Dr. Modic reported, is that it did not. The patients who knew recovered no faster than those who did not know. However, Dr. Modic said, there was one effect of being told — patients felt worse about themselves when they knew they had a bulging disk.
“If I tell you that you have a degenerated disk, basically I’m telling you you’re ugly,” Dr. Modic said.
Scans, he said, are presurgical tools, not screening tools. A scan can help a surgeon before he or she operates, but it does not help with a diagnosis.
“If a patient has back or leg pain, they should be treated conservatively for at least eight weeks,” Dr. Modic said, meaning that they take pain relievers and go about their normal lives. “Then you should do imaging only if you are going to do surgery."
