Medicare has helped make thousands of doctors into multi-millionaires, according to new data released by the federal healthcare program that shows just 2% of practitioners accepting the insurance received nearly a quarter of all payments.

The 24% of all payments made to this small group amounted to $15 billion of the $77 billion in taxpayer money paid out by Medicare in 2012.

The New York Times reported that a hundred physicians alone took in $610 million that year. This group included a Florida ophthalmologist, Salomen E. Melgen, who was paid $21 million, as well as dozens of doctors, primarily eye and cancer specialists, who received more than $4 million apiece.

Thousands of ophthalmologists, in fact, have done well by treating macular degeneration in seniors. The numbers: 3,300 of these eye doctors received $3.3 billion from Medicare.

Clinical laboratories and ambulance services account for about $13.5 billion of the $77 billion total.

The release of the Medicare data has been long overdue, according to critics of the entitlement program. But it took years of litigation, which included staunch opposition from the American Medical Association, before a federal judge last year lifted a decades-old injunction preventing the disclosure.

“This is actually the most useful data set that Medicare has ever released,” Dr. Bob Kocher, a former Obama administration official and current partner at Venrock, a venture capital firm, told The New York Times.

Other observers said the information could spur more lawsuits involving Medicare fraud. “There’s a lot of potential for whistleblowers and justified worry for fraudsters,” attorney Steven F. Grover, who represents whistleblowers, told the Times. “There’s going to be a lot of litigation over this,” he said.

The Los Angeles Times reported that the two highest-paid doctors listed in the Medicare data are being investigated by the government for improper billing. Salomon Melgen, the Florida ophthalmologist, and cardiologist Asad Qamar have both contributed heavily to the political campaigns of Democratic candidates in Florida.

-Noel Brinkerhoff

To Learn More:

Sliver of Medicare Doctors Get Big Share of Payouts (by Reed Abelson and Sarah Cohen, New York Times)

Political Ties of Top Billers for Medicare (by Frances Robles and Eric Lipton, New York Times)

Release of Medicare Doctor Payments Shows Some Huge Payouts (by Chad Terhune, Noam N. Levey and Doug Smith, Los Angeles Times)

Details of Medicare Payments to Doctors Finally Go Public after 35 Years (by Noel Brinkerhoff, AllGov)

Judge Ends 33-Year Ban on Media Access to Medicare Database (by Noel Brinkerhoff, AllGov)