For years, medical students who chose a residency in radiology were said to be on the ROAD to happiness. The acronym highlighted the specialties — radiology, ophthalmology, anesthesiology and dermatology — said to promise the best lifestyle for doctors, including the most money for the least grueling work. Not anymore. Radiologists still make twice as much as family doctors, but are high on the list of specialists whose incomes are in steepest decline. Recent radiology graduates with huge medical school debts are having trouble finding work, let alone the $400,000-and-up dream jobs that beckoned as they signed on for five to seven years of relatively low-paid labor as trainees. On Internet forums, younger radiology residents agonize about whether it is too late to switch tracks.