to a narrowing. Once in position, the balloon is inflated,
compressing the fatty plaque against the artery walls and
restoring free blood flow. Soon the balloons were augmented
with tiny rotary saws, lasers, and targeted medicines.
Researchers also created collapsible baskets to
snare kidney or gall stones for removal without an open
surgical incision. Recently, stents (metal or plastic
sleeves) have been developed for insertion into arteries
or other vessels to keep critical spots from narrowing
after the angioplastic procedure. Not all patients respond
to these procedures, but those who do save considerable
trauma and cost, sometimes even returning home the
day of the procedure.
Of course, not all new ideas have been as fruitful as
CT and MR and linacs. Hopes that the body’s natural heat
emissions could be a diagnostic tool were dashed when
the heat-induced images, or thermograms, could not
be correlated with disease problems. The use of oxygen
potentiation devices like pressure chambers to treat
cancer patients promised to help those with anoxic
tumors. But after some years of tests, the results failed
to justify the efforts. More recently, radiation oncologists
have been experimenting with heat as a radiation
potentiator. However, the technical problems of controlled
heating of a single body area during radiation have
not yet been overcome.
While diagnostic and therapeutic radiology have
developed as separate and defined disciplines, there have
always been synergisms with other medical specialties.
Some two-thirds of all American cancer patients receive
high energy radiation as a portion of their treatment.
Currently, most cancer centers attack most forms of
cancer with a combination of surgery, radiation, cancerkilling
chemicals, and even monoclonal antibodies or
immunological agents.