type of administration contemplated for example parenteral formulations for 19 f imaging advantageously contain a sterile aqueous solution or suspension of a trifluoromethyl mrcm according to this invention various techniques for preparing suitable pharmaceutical solutions and suspensions are known in the art such solutions also may contain pharmaceutically acceptable buffers stabilizers antioxidants and electrolytes such as sodium chloride parenteral compositions may be injected directly or mixed with a large volume parenteral composition for systemic administration formulations for enteral administration may vary widely as is well known in the art in general such formulations include a diagnostically effective amount of a 19 f mrcm in an aqueous solution or suspension such enteral compositions may optionally include buffers surfactants adjuvants thixotropic agents and the like compositions for oral administration may also contain flavoring agents and other ingredients for enhancing their organoleptic qualities the diagnostic compositions within the scope of the present invention are administered in doses effective to achieve the desired enhancement of the nmr image such doses may vary widely depending upon the degree of fluorination the organs or tissues which are the subject of the imaging procedure the nmr imaging equipment being used etc typical doses of the diagnostic compositions.