Economic/reimbursement issues in MR imaging with gadolinium contrast agents

Implementation of an accurate, reliable index of cost effectiveness would help to advance technology assessment and reimbursement of MR imaging procedures, including gadolinium enhancement. To this end, an objective, consensual measure that satisfies the need for "gold-standard" confirmation of diagnostic impressions in routine clinical practice and limits interpreter bias has been developed. Eponymously termed Diagnostic Merit, this barometer is expressed as the percentage of independent judges confirming diagnostic impressions entered by case-blinded radiologists assigned unenhanced and enhanced image sets for interpretation. The judges, who are informed of clinical indications, clinical follow-up, and unblinded diagnostic interpretation of the MR scans, confirm only those case-blind interpretations deemed "close enough for diagnostic utility" to actual clinical profiles. According to this method, gadopentetate dimeglumine has been shown to be cost effective by promoting optimal diagnostic performance. This improvement in utility offsets the cost of the gadolinium contrast agent. Efficacies of gadodiamide and gadoteridol, two other contrast agents in development, have been demonstrated by other measures but are probably also evaluable through the Diagnostic Merit method. CPT-4 codes for contrast-enhanced MR imaging are reviewed.