The system for bringing new medical devices to clinical practice is fundamentally flawed. The current situation involving mechanical devices for stroke intervention is a case in point. A more systematic method that involves coordination of the U.S. Food and Drug Administration (FDA), Centers for Medicare and Medicaid Services (CMS) and National Institutes of Health (NIH) would benefit Americans.

Colin P. Derdeyn, M.D.

FDA approval requires clinical trials establishing safety and technical efficacy. Technical efficacy means that the device does what it is supposed to do—for example, the retriever removes a thrombus. Devices are different than drugs, where efficacy is measured by clinical outcome.

CMS bases its reimbursement decision on clinical data and input from physician specialty groups and industry. The level of evidence varies. In the case of mechanical stroke intervention, data were limited to a single large prospective case series compared to historical controls. The device was effective in removing thrombus but there was little evidence that patient outcome improved.

A randomized trial to prove efficacy of endovascular interventions is needed or we have no direct proof that we are doing anyone any good. Issues related to patient selection also remain unresolved. Existing trials are recruiting very slowly, due in part to the strong financial disincentive for a hospital or physician to participate in a clinical trial with a medical arm.

A better system may be for a pre-determined period of provisional approval and reimbursement after FDA approval, with mandatory outcomes reporting. This would allow physicians to gain experience, make design iterations and optimize patient selection. If outcome data were compelling, no randomized trial would be needed. Otherwise, an NIH-funded trial could then be designed. Reimbursement would be limited to device use in the trial until completion.

Such a new track would allow proof of efficacy for devices that truly benefit our patients.

Colin P. Derdeyn, M.D., is a professor of radiology, neurology and neurological surgery and program director for endovascular surgical neuroradiology at the Mallinckrodt Institute of Radiology at Washington University in St. Louis, where he is also director of a National Institutes of Health-funded stroke clinical trials research center. Dr. Derdeyn serves on the RSNA News Editorial Board.