EXHIBIT 21.1 STATE OF NAME OF SUBSIDIARY INCORPORATION - ------------------------------------------------------------------------ -------------------- InSight Health Corp..................................................... Delaware Radiosurgery Centers, Inc............................................. Delaware Mississippi Mobile Technology, Inc.................................... Mississippi Maxum Health Corp....................................................... Delaware Quest Financial Services, Inc......................................... Delaware Maxum Health Services Corp............................................ Delaware Diagnostic Solutions Corp........................................... Delaware Diagnostic Solutions Corp. II..................................... Delaware Diagnos Temps, Inc. Delaware MTS Enterprises, Inc. Texas Maxum Health Services of Arlington, Inc............................. Texas Maxum Health Services of Dallas, Inc................................ Texas Maxum Health Services of North Texas, Inc. Texas NDDC, Inc........................................................... Texas Open MRI, Inc........................................................... Delaware Radiology Services Corp................................................. Delaware Signal Medical Services, Inc............................................ Delaware